Sample records for rotating wave approximation

  1. Symmetric rotating-wave approximation for the generalized single-mode spin-boson system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Albert, Victor V.; Scholes, Gregory D.; Brumer, Paul

    2011-10-15

    The single-mode spin-boson model exhibits behavior not included in the rotating-wave approximation (RWA) in the ultra and deep-strong coupling regimes, where counter-rotating contributions become important. We introduce a symmetric rotating-wave approximation that treats rotating and counter-rotating terms equally, preserves the invariances of the Hamiltonian with respect to its parameters, and reproduces several qualitative features of the spin-boson spectrum not present in the original rotating-wave approximation both off-resonance and at deep-strong coupling. The symmetric rotating-wave approximation allows for the treatment of certain ultra- and deep-strong coupling regimes with similar accuracy and mathematical simplicity as does the RWA in the weak-coupling regime.more » Additionally, we symmetrize the generalized form of the rotating-wave approximation to obtain the same qualitative correspondence with the addition of improved quantitative agreement with the exact numerical results. The method is readily extended to higher accuracy if needed. Finally, we introduce the two-photon parity operator for the two-photon Rabi Hamiltonian and obtain its generalized symmetric rotating-wave approximation. The existence of this operator reveals a parity symmetry similar to that in the Rabi Hamiltonian as well as another symmetry that is unique to the two-photon case, providing insight into the mathematical structure of the two-photon spectrum, significantly simplifying the numerics, and revealing some interesting dynamical properties.« less

  2. Nonperturbative interpretation of the Bloch vector's path beyond the rotating-wave approximation

    NASA Astrophysics Data System (ADS)

    Benenti, Giuliano; Siccardi, Stefano; Strini, Giuliano

    2013-09-01

    The Bloch vector's path of a two-level system exposed to a monochromatic field exhibits, in the regime of strong coupling, complex corkscrew trajectories. By considering the infinitesimal evolution of the two-level system when the field is treated as a classical object, we show that the Bloch vector's rotation speed oscillates between zero and twice the rotation speed predicted by the rotating wave approximation. Cusps appear when the rotation speed vanishes. We prove analytically that in correspondence to cusps the curvature of the Bloch vector's path diverges. On the other hand, numerical data show that the curvature is very large even for a quantum field in the deep quantum regime with mean number of photons n¯≲1. We finally compute numerically the typical error size in a quantum gate when the terms beyond rotating wave approximation are neglected.

  3. Analytical approximations for spiral waves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Löber, Jakob, E-mail: jakob@physik.tu-berlin.de; Engel, Harald

    2013-12-15

    We propose a non-perturbative attempt to solve the kinematic equations for spiral waves in excitable media. From the eikonal equation for the wave front we derive an implicit analytical relation between rotation frequency Ω and core radius R{sub 0}. For free, rigidly rotating spiral waves our analytical prediction is in good agreement with numerical solutions of the linear eikonal equation not only for very large but also for intermediate and small values of the core radius. An equivalent Ω(R{sub +}) dependence improves the result by Keener and Tyson for spiral waves pinned to a circular defect of radius R{sub +}more » with Neumann boundaries at the periphery. Simultaneously, analytical approximations for the shape of free and pinned spirals are given. We discuss the reasons why the ansatz fails to correctly describe the dependence of the rotation frequency on the excitability of the medium.« less

  4. Cavity losses for the dissipative Jaynes Cummings Hamiltonian beyond rotating wave approximation

    NASA Astrophysics Data System (ADS)

    Scala, M.; Militello, B.; Messina, A.; Maniscalco, S.; Piilo, J.; Suominen, K.-A.

    2007-11-01

    A microscopic derivation of the master equation for the Jaynes-Cummings model with cavity losses is given, taking into account the terms in the dissipator which vary with frequencies of the order of the vacuum Rabi frequency. Our approach allows us to single out physical contexts wherein the usual phenomenological dissipator turns out to be fully justified and constitutes an extension of our previous analysis (Scala et al 2007 Phys. Rev. A 75 013811), where a microscopic derivation was given in the framework of the rotating wave approximation.

  5. Ladder operators and coherent states for the Jaynes-Cummings model in the rotating-wave approximation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hussin, V.; Nieto, L.M.

    2005-12-15

    Using algebraic techniques, we realize a systematic search of different types of ladder operators for the Jaynes-Cummings model in the rotating-wave approximation. The link between our results and previous studies on the diagonalization of the associated Hamiltonian is established. Using some of the ladder operators obtained before, examples are given on the possibility of constructing a variety of interesting coherent states for this Hamiltonian.

  6. Uniform analytic approximation of Wigner rotation matrices

    NASA Astrophysics Data System (ADS)

    Hoffmann, Scott E.

    2018-02-01

    We derive the leading asymptotic approximation, for low angle θ, of the Wigner rotation matrix elements, dm1m2 j(θ ) , uniform in j, m1, and m2. The result is in terms of a Bessel function of integer order. We numerically investigate the error for a variety of cases and find that the approximation can be useful over a significant range of angles. This approximation has application in the partial wave analysis of wavepacket scattering.

  7. Fano-Agarwal couplings and non-rotating wave approximation in single-photon timed Dicke subradiance

    NASA Astrophysics Data System (ADS)

    Mirza, Imran M.; Begzjav, Tuguldur

    2016-04-01

    Recently a new class of single-photon timed Dicke (TD) subradiant states has been introduced with possible applications in single-photon-based quantum information storage and on demand ultrafast retrieval (Scully M. O., Phys. Rev. Lett., 115 (2015) 243602). However, the influence of any kind of virtual processes on the decay of these new kind of subradiant states has been left as an open question. In the present paper, we focus on this problem in detail. In particular, we investigate how pure Fano-Agarwal couplings and other virtual processes arising from non-rotating wave approximation impact the decay of otherwise sub- and superradiant states. In addition to the overall virtual couplings among all TD states, we also focus on the dominant role played by the couplings between specific TD states.

  8. Entanglement dynamics of two independent Jaynes-Cummings atoms without the rotating-wave approximation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen Qinghu; Department of Physics, Zhejiang University, Hangzhou 310027; Yang Yuan

    2010-11-15

    Entanglement evolution of two independent Jaynes-Cummings atoms without the rotating-wave approximation (RWA) is studied by a numerically exact approach. Previous results based on the RWA are essentially modified in the strong-coupling regime (g{>=}0.1), which has been reached in the recent experiments on the flux qubit coupled to the LC resonator. For the initial Bell state with anticorrelated spins, entanglement sudden death (ESD) is absent in the RWA but does appear in the present numerical calculation without the RWA. Aperiodic entanglement evolution in the strong-coupling regime is observed. The strong atom-cavity coupling facilitates the ESD. The sign of the detuning playsmore » an essential role in the entanglement evolution for strong coupling, which is irrelevant in the RWA. Analytical results based on an unitary transformation are also given, which could not modify the RWA picture essentially. It is suggested that the activation of the photons may be the origin of ESD in this system.« less

  9. Solitary waves in shallow water hydrodynamics and magnetohydrodynamics in rotating spherical coordinates

    NASA Astrophysics Data System (ADS)

    London, Steven D.

    2018-01-01

    In a recent paper (London, Geophys. Astrophys. Fluid Dyn. 2017, vol. 111, pp. 115-130, referred to as L1), we considered a perfect electrically conducting rotating fluid in the presence of an ambient toroidal magnetic field, governed by the shallow water magnetohydrodynamic (MHD) equations in a modified equatorial ?-plane approximation. In conjunction with a WKB type approximation, we used a multiple scale asymptotic scheme, previously developed by Boyd (J. Phys. Oceanogr. 1980, vol. 10, pp. 1699-1717) for equatorial solitary hydrodynamic waves, and found solitary MHD waves. In this paper, as in L1, we apply a WKB type approximation in order to extend the results of L1 from the modified ?-plane to the full spherical geometry. We have included differential rotation in the analysis in order to make the results more relevant to the solar case. In addition, we consider the case of hydrodynamic waves on the rotating sphere in the presence of a differential rotation intended to roughly model the varying large scale currents in the oceans and atmosphere. In the hydrodynamic case, we find the usual equatorial solitary waves as found by Boyd, as well as waves in bands away from the equator for sufficiently strong currents. In the MHD case, we find basically the same equatorial waves found in L1. L1 also found non-equatorial modes; no such modes are found in the full spherical geometry.

  10. Absence of Vacuum Induced Berry Phases without the Rotating Wave Approximation in Cavity QED

    NASA Astrophysics Data System (ADS)

    Larson, Jonas

    2012-01-01

    We revisit earlier studies on Berry phases suggested to appear in certain cavity QED settings. It has been especially argued that a nontrivial geometric phase is achievable even in the situation of no cavity photons. We, however, show that such results hinge on imposing the rotating wave approximation (RWA), while without the RWA no Berry phases occur in these schemes. A geometrical interpretation of our results is obtained by introducing semiclassical energy surfaces which in a simple way brings out the phase-space dynamics. With the RWA, a conical intersection between the surfaces emerges and encircling it gives rise to the Berry phase. Without the RWA, the conical intersection is absent and therefore the Berry phase vanishes. It is believed that this is a first example showing how the application of the RWA in the Jaynes-Cummings model may lead to false conclusions, regardless of the mutual strengths between the system parameters.

  11. Analytical solution and applications of three qubits in three coupled modes without rotating wave approximation

    NASA Astrophysics Data System (ADS)

    Zhang, Jian-Song; Zhang, Liu-Juan; Chen, Ai-Xi; Abdel-Aty, Mahmoud

    2018-06-01

    We study the dynamics of the three-qubit system interacting with multi-mode without rotating wave approximation (RWA). A physical realization of the system without direct qubits interactions with dephasing bath is proposed. It is shown that non-Markovian characters of the purity of the three qubits and the coupling strength of modes are stronger enough the RWA is no longer valid. The influences of the dephasing of qubits and interactions of modes on the dynamics of genuine multipartite entanglement and bipartite correlations of qubits are investigated. The multipartite and bipartite quantum correlations could be generated faster if we increase the coupling strength of modes and the RWA is not valid when the coupling strength is strong enough. The unitary transformations approach adopted here can be extended to other systems such as circuit or cavity quantum electrodynamic systems in the strong coupling regime.

  12. Generalized squeezing rotating-wave approximation to the isotropic and anisotropic Rabi model in the ultrastrong-coupling regime

    NASA Astrophysics Data System (ADS)

    Zhang, Yu-Yu

    2016-12-01

    Generalized squeezing rotating-wave approximation (GSRWA) is proposed by employing both the displacement and the squeezing transformations. A solvable Hamiltonian is reformulated in the same form as the ordinary RWA ones. For a qubit coupled to oscillators experiment, a well-defined Schrödinger-cat-like entangled state is given by the displaced-squeezed oscillator state instead of the original displaced state. For the isotropic Rabi case, the mean photon number and the ground-state energy are expressed analytically with additional squeezing terms, exhibiting a substantial improvement of the GSRWA. And the ground-state energy in the anisotropic Rabi model confirms the effectiveness of the GSRWA. Due to the squeezing effect, the GSRWA improves the previous methods only with the displacement transformation in a wide range of coupling strengths even for large atom frequency.

  13. Axisymmetric modes of rotating relativistic stars in the Cowling approximation

    NASA Astrophysics Data System (ADS)

    Font, José A.; Dimmelmeier, Harald; Gupta, Anshu; Stergioulas, Nikolaos

    2001-08-01

    Axisymmetric pulsations of rotating neutron stars can be excited in several scenarios, such as core collapse, crust- and core-quakes or binary mergers, and could become detectable in either gravitational waves or high-energy radiation. Here, we present a comprehensive study of all low-order axisymmetric modes of uniformly and rapidly rotating relativistic stars. Initial stationary configurations are appropriately perturbed and are numerically evolved using an axisymmetric, non-linear relativistic hydrodynamics code, assuming time-independence of the gravitational field (Cowling approximation). The simulations are performed using a high-resolution shock-capturing finite-difference scheme accurate enough to maintain the initial rotation law for a large number of rotational periods, even for stars at the mass-shedding limit. Through Fourier transforms of the time evolution of selected fluid variables, we compute the frequencies of quasi-radial and non-radial modes with spherical harmonic indices l=0, 1, 2 and 3, for a sequence of rotating stars from the non-rotating limit to the mass-shedding limit. The frequencies of the axisymmetric modes are affected significantly by rotation only when the rotation rate exceeds about 50 per cent of the maximum allowed. As expected, at large rotation rates, apparent mode crossings between different modes appear. In addition to the above modes, several axisymmetric inertial modes are also excited in our numerical evolutions.

  14. Coupled modes locally interacting with qubits: Critical assessment of the rotating-wave approximation

    NASA Astrophysics Data System (ADS)

    Cárdenas, P. C.; Teixeira, W. S.; Semião, F. L.

    2017-04-01

    The interaction of qubits with quantized modes of electromagnetic fields has been largely addressed in the quantum optics literature under the rotating wave approximation (RWA), where rapid oscillating terms in the qubit-mode interaction picture Hamiltonian can be neglected. At the same time, it is generally accepted that, provided the interaction is sufficiently strong or for long times, the RWA tends to describe physical phenomena incorrectly. In this work, we extend the investigation of the validity of the RWA to a more involved setup where two qubit-mode subsystems are brought to interaction through their harmonic coordinates. Our treatment is all analytic thanks to a sequence of carefully chosen unitary transformations, which allows us to diagonalize the Hamiltonian within and without the RWA. By also considering qubit dephasing, we find that the purity of the two-qubit state presents non-Markovian features which become more pronounced as the coupling between the modes gets stronger and the RWA loses its validity. In the same regime, there occurs fast generation of entanglement between the qubits, which is also not correctly described under the RWA. The setup and results presented here clearly show the limitations of the RWA in a scenario amenable to exact description and free from numerical uncertainties. Consequently, it may be of interest for the community working with cavity or circuit quantum electrodynamic systems in the strong coupling regime.

  15. Wave-particle interactions in rotating mirrorsa)

    NASA Astrophysics Data System (ADS)

    Fetterman, Abraham J.; Fisch, Nathaniel J.

    2011-05-01

    Wave-particle interactions in E ×B rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy. This wave-particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas, the alpha particles may be removed at low energy through the loss cone, and the energy lost may be transferred to the radial electric field. This eliminates the need for electrodes in the mirror throat, which have presented serious technical issues in past rotating plasma devices. A particularly simple way to achieve this effect is to use a high azimuthal mode number perturbation on the magnetic field. Rotation can also be sustained by waves in plasmas without a kinetic energy source. This type of wave has been considered for plasma centrifuges used for isotope separation. Energy may also be transferred from the electric field to particles or waves, which may be useful for ion heating and energy generation.

  16. Theory of inertial waves in rotating fluids

    NASA Astrophysics Data System (ADS)

    Gelash, Andrey; L'vov, Victor; Zakharov, Vladimir

    2017-04-01

    The inertial waves emerge in the geophysical and astrophysical flows as a result of Earth rotation [1]. The linear theory of inertial waves is known well [2] while the influence of nonlinear effects of wave interactions are subject of many recent theoretical and experimental studies. The three-wave interactions which are allowed by inertial waves dispersion law (frequency is proportional to cosine of the angle between wave direction and axes of rotation) play an exceptional role. The recent studies on similar type of waves - internal waves, have demonstrated the possibility of formation of natural wave attractors in the ocean (see [3] and references herein). This wave focusing leads to the emergence of strong three-wave interactions and subsequent flows mixing. We believe that similar phenomena can take place for inertial waves in rotating flows. In this work we present theoretical study of three-wave and four-wave interactions for inertial waves. As the main theoretical tool we suggest the complete Hamiltonian formalism for inertial waves in rotating incompressible fluids [4]. We study three-wave decay instability and then present statistical description of inertial waves in the frame of Hamiltonian formalism. We obtain kinetic equation, anisotropic wave turbulence spectra and study the problem of parametric wave turbulence. These spectra were previously found in [5] by helicity decomposition method. Taking this into account we discuss the advantages of suggested Hamiltonian formalism and its future applications. Andrey Gelash thanks support of the RFBR (Grant No.16-31-60086 mol_a_dk) and Dr. E. Ermanyuk, Dr. I. Sibgatullin for the fruitful discussions. [1] Le Gal, P. Waves and instabilities in rotating and stratified flows, Fluid Dynamics in Physics, Engineering and Environmental Applications. Springer Berlin Heidelberg, 25-40, 2013. [2] Greenspan, H. P. The theory of rotating fluids. CUP Archive, 1968. [3] Brouzet, C., Sibgatullin, I. N., Scolan, H., Ermanyuk, E

  17. Rotational motions for teleseismic surface waves

    NASA Astrophysics Data System (ADS)

    Lin, Chin-Jen; Huang, Han-Pang; Pham, Nguyen Dinh; Liu, Chun-Chi; Chi, Wu-Cheng; Lee, William H. K.

    2011-08-01

    We report the findings for the first teleseismic six degree-of-freedom (6-DOF) measurements including three components of rotational motions recorded by a sensitive rotation-rate sensor (model R-1, made by eentec) and three components of translational motions recorded by a traditional seismometer (STS-2) at the NACB station in Taiwan. The consistent observations in waveforms of rotational motions and translational motions in sections of Rayleigh and Love waves are presented in reference to the analytical solution for these waves in a half space of Poisson solid. We show that additional information (e.g., Rayleigh wave phase velocity, shear wave velocity of the surface layer) might be exploited from six degree-of-freedom recordings of teleseismic events at only one station. We also find significant errors in the translational records of these teleseismic surface waves due to the sensitivity of inertial translation sensors (seismometers) to rotational motions. The result suggests that the effects of such errors need to be counted in surface wave inversions commonly used to derive earthquake source parameters and Earth structure.

  18. 3D MHD Simulations of Waves Excited in an Accretion Disk by a Rotating Magnetized Star

    NASA Astrophysics Data System (ADS)

    Lovelace, R. V. E.; Romanova, M. M.

    2014-01-01

    We present results of global 3D MHD simulations of warp and density waves in accretion disks excited by a rotating star with a misaligned dipole magnetic field. A wide range of cases are considered. We find for example that if the star's magnetosphere corotates approximately with the inner disk, then a strong one-arm bending wave or warp forms. The warp corotates with the star and has a maximum amplitude (|zω|/r ~ 0.3) between the corotation radius and the radius of the vertical resonance. If the magnetosphere rotates more slowly than the inner disk, then a bending wave is excited at the disk-magnetosphere boundary, but it does not form a large-scale warp. In this case the angular rotation of the disk [Ω(r,z = 0)] has a maximum as a function of r so that there is an inner region where dΩ/dr > 0. In this region we observe radially trapped density waves in approximate agreement with the theoretical prediction of a Rossby wave instability in this region.

  19. Wave induced supersonic rotation in mirrors

    NASA Astrophysics Data System (ADS)

    Fetterman, Abraham

    2010-11-01

    Wave-particle interactions in ExB supersonically rotating plasmas feature an unusual effect: particles are diffused by waves in both potential energy and kinetic energy [1]. This wave-particle interaction generalizes the alpha channeling effect, in which radio frequency waves are used to remove alpha particles collisionlessly at low energy. In rotating plasmas, the alpha particles may be removed at low energy through the loss cone, and the energy lost may be transferred to the radial electric field. This eliminates the need for electrodes in the mirror throat, which have presented serious technical issues in past rotating plasma devices. A particularly simple way to achieve this effect is to use a high azimuthal mode number perturbation on the magnetic field [2]. In the rotating frame, this perturbation is seen as a wave near the alpha particle cyclotron harmonic, and can break the azimuthal symmetry and magnetic moment conservation without changing the particle's total energy. The particle may exit if it reduces its kinetic energy and becomes more trapped if it gains kinetic energy, leading to a steady state current that maintains the field. Simulations of single particles in rotating mirrors show that a stationary wave can extract enough energy from alpha particles for a reactor to be self-sustaining. Rotation can also be sustained by waves in plasmas without a kinetic energy source. This type of wave has been considered for plasma centrifuges used for isotope separation [3]. [4pt] [1] A. J. Fetterman and N. J. Fisch, Phys Rev Lett 101, 205003 (2008). [0pt] [2] A. J. Fetterman and N. J. Fisch, Phys. Plasmas 17, 042112 (2010). [0pt] [3] A. J. Fetterman and N. J. Fisch, Plasma Sources Sci. Tech. 18, 045003 (2009).

  20. Inertial wave beams and inertial wave modes in a rotating cylinder with time-modulated rotation rate

    NASA Astrophysics Data System (ADS)

    Borcia, Ion D.; Ghasemi V., Abouzar; Harlander, Uwe

    2014-05-01

    Inertial gravity waves play an crucial role in atmospheres, oceans, and the fluid inside of planets and moons. In the atmosphere, the effect of rotation is neglected for small wavelength and the waves bear the character of internal gravity waves. For long waves, the hydrostatic assumption is made which in turn makes the atmosphere inelastic with respect to inertial motion. In contrast, in the Earth's interior, pure inertial waves are considered as an important fundamental part of the motion. Moreover, as the deep ocean is nearly homogeneous, there the inertial gravity waves bear the character of inertial waves. Excited at the oceans surface mainly due to weather systems the waves can propagate downward and influence the deep oceans motion. In the light of the aforesaid it is important to understand better fundamental inertial wave dynamics. We investigate inertial wave modes by experimental and numerical methods. Inertial modes are excited in a fluid filled rotating annulus by modulating the rotation rate of the outer cylinder and the upper and lower lids. This forcing leads to inertial wave beams emitted from the corner regions of the annulus due to periodic motions in the boundary layers (Klein et al., 2013). When the forcing frequency matches with the eigenfrequency of the rotating annulus the beam pattern amplitude is increasing, the beams broaden and mode structures can be observed (Borcia et al., 2013a). The eigenmodes are compared with analytical solutions of the corresponding inviscid problem (Borcia et al, 2013b). In particular for the pressure field a good agreement can be found. However, shear layers related to the excited wave beams are present for all frequencies. This becomes obvious in particular in the experimental visualizations that are done by using Kalliroscope particles, highlighting relative motion in the fluid. Comparing the eigenfrequencies we find that relative to the analytical frequencies, the experimental and numerical ones show a small

  1. Advances in wave turbulence: rapidly rotating flows

    NASA Astrophysics Data System (ADS)

    Cambon, C.; Rubinstein, R.; Godeferd, F. S.

    2004-07-01

    At asymptotically high rotation rates, rotating turbulence can be described as a field of interacting dispersive waves by the general theory of weak wave turbulence. However, rotating turbulence has some complicating features, including the anisotropy of the wave dispersion relation and the vanishing of the wave frequency on a non-vanishing set of 'slow' modes. These features prevent straightforward application of existing theories and lead to some interesting properties, including the transfer of energy towards the slow modes. This transfer competes with, and might even replace, the transfer to small scales envisioned in standard turbulence theories. In this paper, anisotropic spectra for rotating turbulence are proposed based on weak turbulence theory; some evidence for their existence is given based on numerical calculations of the wave turbulence equations. Previous arguments based on the properties of resonant wave interactions suggest that the slow modes decouple from the others. Here, an extended wave turbulence theory with non-resonant interactions is proposed in which all modes are coupled; these interactions are possible only because of the anisotropy of the dispersion relation. Finally, the vanishing of the wave frequency on the slow modes implies that these modes cannot be described by weak turbulence theory. A more comprehensive approach to rotating turbulence is proposed to overcome this limitation.

  2. Circularly polarized few-cycle optical rogue waves: rotating reduced Maxwell-Bloch equations.

    PubMed

    Xu, Shuwei; Porsezian, K; He, Jingsong; Cheng, Yi

    2013-12-01

    The rotating reduced Maxwell-Bloch (RMB) equations, which describe the propagation of few-cycle optical pulses in a transparent media with two isotropic polarized electronic field components, are derived from a system of complete Maxwell-Bloch equations without using the slowly varying envelope approximations. Two hierarchies of the obtained rational solutions, including rogue waves, which are also called few-cycle optical rogue waves, of the rotating RMB equations are constructed explicitly through degenerate Darboux transformation. In addition to the above, the dynamical evolution of the first-, second-, and third-order few-cycle optical rogue waves are constructed with different patterns. For an electric field E in the three lower-order rogue waves, we find that rogue waves correspond to localized large amplitude oscillations of the polarized electric fields. Further a complementary relationship of two electric field components of rogue waves is discussed in terms of analytical formulas as well as numerical figures.

  3. Freely-tunable broadband polarization rotator for terahertz waves

    NASA Astrophysics Data System (ADS)

    Peng, Ru-Wen; Fan, Ren-Hao; Zhou, Yu; Jiang, Shang-Chi; Xiong, Xiang; Huang, Xian-Rong; Wang, Mu

    It is known that commercially-available terahertz (THz) emitters usually generate linearly polarized waves only along certain directions, but in practice, a polarization rotator that is capable of rotating the polarization of THz waves to any direction is particularly desirable and it will have various important applications. In this work, we demonstrate a freely tunable polarization rotator for broadband THz waves using a three-rotating-layer metallic grating structure, which can conveniently rotate the polarization of a linearly polarized THz wave to any desired direction with nearly perfect conversion efficiency. The device performance has been experimentally demonstrated by both THz transmission spectra and direct imaging. The polarization rotation originates from multi wave interference in the three-layer grating structure based on the scattering-matrix analysis. We can expect that this active broadband polarization rotator has wide applications in analytical chemistry, biology, communication technology, imaging, etc.. Reference: R. H. Fan, Y. Zhou, X. P. Ren, R. W. Peng, S. C. Jiang, D. H. Xu, X. Xiong, X. R. Huang, and Mu Wang, Advanced Materials 27,1201(2015). Freely-tunable broadband polarization rotator for terahertz waves.

  4. The Inhomogeneous Waves in a Rotating Piezoelectric Body

    PubMed Central

    Chen, Si

    2013-01-01

    This paper presents the analysis and numerical results of rotation, propagation angle, and attenuation angle upon the waves propagating in the piezoelectric body. Via considering the centripetal and Coriolis accelerations in the piezoelectric equations with respect to a rotating frame of reference, wave velocities and attenuations are derived and plotted graphically. It is demonstrated that rotation speed vector can affect wave velocities and make the piezoelectric body behaves as if it was damping. Besides, the effects of propagation angle and attenuation angle are presented. Critical point is found when rotation speed is equal to wave frequency, around which wave characteristics change drastically. PMID:24298219

  5. Gravitational-wave emission from rotating gravitational collapse in three dimensions.

    PubMed

    Baiotti, L; Hawke, I; Rezzolla, L; Schnetter, E

    2005-04-08

    We present the first three-dimensional (3D) calculations of the gravitational-wave emission in the collapse of uniformly rotating stars to black holes. The initial models are polytropes which are dynamically unstable and near the mass-shedding limit. The waveforms have been extracted using a gauge-invariant approach and reflect the properties of both the initial stellar models and of newly produced black holes, being in good qualitative agreement with those computed in previous 2D simulations. The wave amplitudes, however, are about 1 order of magnitude smaller, giving, for a source at 10 kpc, a signal-to-noise ratio S/N approximately 0.25 for LIGO-VIRGO and S/N less than or approximately equal 4 for LIGO II.

  6. (p,q) deformations and (p,q)-vector coherent states of the Jaynes-Cummings model in the rotating wave approximation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ben Geloun, Joseph; Govaerts, Jan; Hounkonnou, M. Norbert

    2007-03-15

    Classes of (p,q) deformations of the Jaynes-Cummings model in the rotating wave approximation are considered. Diagonalization of the Hamiltonian is performed exactly, leading to useful spectral decompositions of a series of relevant operators. The latter include ladder operators acting between adjacent energy eigenstates within two separate infinite discrete towers, except for a singleton state. These ladder operators allow for the construction of (p,q)-deformed vector coherent states. Using (p,q) arithmetics, explicit and exact solutions to the associated moment problem are displayed, providing new classes of coherent states for such models. Finally, in the limit of decoupled spin sectors, our analysis translatesmore » into (p,q) deformations of the supersymmetric harmonic oscillator, such that the two supersymmetric sectors get intertwined through the action of the ladder operators as well as in the associated coherent states.« less

  7. Rotation-induced nonlinear wavepackets in internal waves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Whitfield, A. J., E-mail: ashley.whitfield.12@ucl.ac.uk; Johnson, E. R., E-mail: e.johnson@ucl.ac.uk

    2014-05-15

    The long time effect of weak rotation on an internal solitary wave is the decay into inertia-gravity waves and the eventual formation of a localised wavepacket. Here this initial value problem is considered within the context of the Ostrovsky, or the rotation-modified Korteweg-de Vries (KdV), equation and a numerical method for obtaining accurate wavepacket solutions is presented. The flow evolutions are described in the regimes of relatively-strong and relatively-weak rotational effects. When rotational effects are relatively strong a second-order soliton solution of the nonlinear Schrödinger equation accurately predicts the shape, and phase and group velocities of the numerically determined wavepackets.more » It is suggested that these solitons may form from a local Benjamin-Feir instability in the inertia-gravity wave-train radiated when a KdV solitary wave rapidly adjusts to the presence of strong rotation. When rotational effects are relatively weak the initial KdV solitary wave remains coherent longer, decaying only slowly due to weak radiation and modulational instability is no longer relevant. Wavepacket solutions in this regime appear to consist of a modulated KdV soliton wavetrain propagating on a slowly varying background of finite extent.« less

  8. The exact thermal rotational spectrum of a two-dimensional rigid rotor obtained using Gaussian wave packet dynamics

    NASA Technical Reports Server (NTRS)

    Reimers, J. R.; Heller, E. J.

    1985-01-01

    The exact thermal rotational spectrum of a two-dimensional rigid rotor is obtained using Gaussian wave packet dynamics. The spectrum is obtained by propagating, without approximation, infinite sets of Gaussian wave packets. These sets are constructed so that collectively they have the correct periodicity, and indeed, are coherent states appropriate to this problem. Also, simple, almost classical, approximations to full wave packet dynamics are shown to give results which are either exact or very nearly exact. Advantages of the use of Gaussian wave packet dynamics over conventional linear response theory are discussed.

  9. Surface acoustic wave micromotor with arbitrary axis rotational capability

    NASA Astrophysics Data System (ADS)

    Tjeung, Ricky T.; Hughes, Mark S.; Yeo, Leslie Y.; Friend, James R.

    2011-11-01

    A surface acoustic wave (SAW) actuated rotary motor is reported here, consisting of a millimeter-sized spherical metal rotor placed on the surface of a lead zirconate titanate piezoelectric substrate upon which the SAW is made to propagate. At the design frequency of 3.2 MHz and with a fixed preload of 41.1 μN, the maximum rotational speed and torque achieved were approximately 1900 rpm and 5.37 μN-mm, respectively, producing a maximum output power of 1.19 μW. The surface vibrations were visualized using laser Doppler vibrometry and indicate that the rotational motion arises due to retrograde elliptical motions of the piezoelectric surface elements. Rotation about orthogonal axes in the plane of the substrate has been obtained by using orthogonally placed interdigital electrodes on the substrate to generate SAW impinging on the rotor, offering a means to generate rotation about an arbitrary axis in the plane of the substrate.

  10. Translation of waves along quantum vortex filaments in the low-temperature two-dimensional local induction approximation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Van Gorder, Robert A., E-mail: Robert.VanGorder@maths.ox.ac.uk

    2015-09-15

    In a recent paper, we give a study of the purely rotational motion of general stationary states in the two-dimensional local induction approximation (2D-LIA) governing superfluid turbulence in the low-temperature limit [B. Svistunov, “Superfluid turbulence in the low-temperature limit,” Phys. Rev. B 52, 3647 (1995)]. Such results demonstrated that variety of stationary configurations are possible from vortex filaments exhibiting purely rotational motion in addition to commonly discussed configurations such as helical or planar states. However, the filaments (or, more properly, waves along these filaments) can also exhibit translational motion along the axis of orientation. In contrast to the study onmore » vortex configurations for purely rotational stationary states, the present paper considers non-stationary states which exhibit a combination of rotation and translational motions. These solutions can essentially be described as waves or disturbances which ride along straight vortex filament lines. As expected from our previous work, there are a number of types of structures that can be obtained under the 2D-LIA. We focus on non-stationary states, as stationary states exhibiting translation will essentially take the form of solutions studied in [R. A. Van Gorder, “General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation,” Phys. Fluids 26, 065105 (2014)], with the difference being translation along the reference axis, so that qualitative appearance of the solution geometry will be the same (even if there are quantitative differences). We discuss a wide variety of general properties of these non-stationary solutions and derive cases in which they reduce to known stationary states. We obtain various routes to Kelvin waves along vortex filaments and demonstrate that if the phase and amplitude of a disturbance both propagate with the same wave speed, then Kelvin waves will result. We also consider

  11. Freely Tunable Broadband Polarization Rotator for Terahertz Waves

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fan, Ren-Hao; Zhou, Yu; Ren, Xiao-Ping

    2014-12-28

    A freely tunable polarization rotator for broadband terahertz waves is demonstrated using a three-rotating-layer metallic grating structure, which can conveniently rotate the polarization of a linearly polarized terahertz wave to any desired direction with nearly perfect conversion efficiency. This low-cost, high-efficiency, and freely tunable device has potential applications as material analysis, wireless communication, and THz imaging.

  12. Gravitational wave content and stability of uniformly, rotating, triaxial neutron stars in general relativity.

    PubMed

    Tsokaros, Antonios; Ruiz, Milton; Paschalidis, Vasileios; Shapiro, Stuart L; Baiotti, Luca; Uryū, Kōji

    2017-06-15

    Targets for ground-based gravitational wave interferometers include continuous, quasiperiodic sources of gravitational radiation, such as isolated, spinning neutron stars. In this work, we perform evolution simulations of uniformly rotating, triaxially deformed stars, the compressible analogs in general relativity of incompressible, Newtonian Jacobi ellipsoids. We investigate their stability and gravitational wave emission. We employ five models, both normal and supramassive, and track their evolution with different grid setups and resolutions, as well as with two different evolution codes. We find that all models are dynamically stable and produce a strain that is approximately one-tenth the average value of a merging binary system. We track their secular evolution and find that all our stars evolve toward axisymmetry, maintaining their uniform rotation, rotational kinetic energy, and angular momentum profiles while losing their triaxiality.

  13. Rotational waves in geodynamics

    NASA Astrophysics Data System (ADS)

    Gerus, Artyom; Vikulin, Alexander

    2015-04-01

    The rotation model of a geoblock with intrinsic momentum was constructed by A.V. Vikulin and A.G. Ivanchin [9, 10] to describe seismicity within the Pacific Ocean margin. It is based on the idea of a rotational motion of geoblocks as the parts of the rotating body of the Earth that generates rotary deformation waves. The law of the block motion was derived in the form of the sine-Gordon equation (SG) [5, 9]; the dimensionless form of the equation is: δ2θ δ2θ δξ2 - δη2 = sinθ, (1) where θ = β/2, ξ = k0z and η = v0k0t are dimensionless coordinates, z - length of the chain of masses (blocks), t - time, β - turn angle, ν0 - representative velocity of the process, k0 - wave number. Another case analyzed was a chain of nonuniformly rotating blocks, with deviation of force moments from equilibrium positions μ, considering friction forces α along boundaries, which better matched a real-life seismic process. As a result, the authors obtained the law of motion for a block in a chain in the form of the modified SG equation [8]: δ2θ δ2θ δθ- δξ2 - δ η2 = sin θ+ α δη + μδ(ξ)sin θ (2)

  14. Multi-scale phenomena of rotation-modified mode-2 internal waves

    NASA Astrophysics Data System (ADS)

    Deepwell, David; Stastna, Marek; Coutino, Aaron

    2018-03-01

    We present high-resolution, three-dimensional simulations of rotation-modified mode-2 internal solitary waves at various rotation rates and Schmidt numbers. Rotation is seen to change the internal solitary-like waves observed in the absence of rotation into a leading Kelvin wave followed by Poincaré waves. Mass and energy is found to be advected towards the right-most side wall (for a Northern Hemisphere rotation), leading to increased amplitude of the leading Kelvin wave and the formation of Kelvin-Helmholtz (K-H) instabilities on the upper and lower edges of the deformed pycnocline. These fundamentally three-dimensional instabilities are localized within a region near the side wall and intensify in vigour with increasing rotation rate. Secondary Kelvin waves form further behind the wave from either resonance with radiating Poincaré waves or the remnants of the K-H instability. The first of these mechanisms is in accord with published work on mode-1 Kelvin waves; the second is, to the best of our knowledge, novel to the present study. Both types of secondary Kelvin waves form on the same side of the channel as the leading Kelvin wave. Comparisons of equivalent cases with different Schmidt numbers indicate that while adopting a numerically advantageous low Schmidt number results in the correct general characteristics of the Kelvin waves, excessive diffusion of the pycnocline and various density features precludes accurate representation of both the trailing Poincaré wave field and the intensity and duration of the Kelvin-Helmholtz instabilities.

  15. Three-Dimensional Visualization of Wave Functions for Rotating Molecule: Plot of Spherical Harmonics

    ERIC Educational Resources Information Center

    Nagaoka, Shin-ichi; Teramae, Hiroyuki; Nagashima, Umpei

    2013-01-01

    At an early stage of learning quantum chemistry, undergraduate students usually encounter the concepts of the particle in a box, the harmonic oscillator, and then the particle on a sphere. Rotational levels of a diatomic molecule can be well approximated by the energy levels of the particle on a sphere. Wave functions for the particle in a…

  16. Extreme-ultraviolet observations of global coronal wave rotation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Attrill, G. D. R.; Long, D. M.; Green, L. M.

    2014-11-20

    We present evidence of global coronal wave rotation in EUV data from SOHO/EIT, STEREO/EUVI, and SDO/AIA. The sense of rotation is found to be consistent with the helicity of the source region (clockwise for positive helicity, anticlockwise for negative helicity), with the source regions hosting sigmoidal structures. We also study two coronal wave events observed by SDO/AIA where no clear rotation (or sigmoid) is observed. The selected events show supporting evidence that they all originate with flux rope eruptions. We make comparisons across this set of observations (both with and without clear sigmoidal structures). On examining the magnetic configuration ofmore » the source regions, we find that the nonrotation events possess a quadrupolar magnetic configuration. The coronal waves that do show a rotation originate from bipolar source regions.« less

  17. Uniform semiclassical sudden approximation for rotationally inelastic scattering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Korsch, H.J.; Schinke, R.

    1980-08-01

    The infinite-order-sudden (IOS) approximation is investigated in the semiclassical limit. A simplified IOS formula for rotationally inelastic differential cross sections is derived involving a uniform stationary phase approximation for two-dimensional oscillatory integrals with two stationary points. The semiclassical analysis provides a quantitative description of the rotational rainbow structure in the differential cross section. The numerical calculation of semiclassical IOS cross sections is extremely fast compared to numerically exact IOS methods, especially if high ..delta..j transitions are involved. Rigid rotor results for He--Na/sub 2/ collisions with ..delta..j< or approx. =26 and for K--CO collisions with ..delta..j< or approx. =70 show satisfactorymore » agreement with quantal IOS calculations.« less

  18. Rotating spiral waves in fertilized ascidian eggs.

    PubMed

    Ballarò, Benedetto; Reas, Pier Giorgio

    2002-01-01

    Excitable systems modelled by reaction-diffusion equation may be expected to produce quite complex spatial patterns. Winfree [1974] demonstrated experimentally, in the Belousov-Zhabotinskii reaction, the existence of particular waves called rotating spiral waves. Later Keener and Tyson [1986] presented a thorough analysis of these waves in excitable systems. Spiral waves can also be observed in brain tissue (Shibata and Bures [1974]), while it seems that the precursor to cardiac fibrillation is the appearance of rotating waves of electrical impulses (Winfree [1983]). In this work we suppose the appearance of Ca++ spiral waves in the vegetal pole of ascidian egg cells after the first ooplasmic segregation. Previously we observed that (Ballarò and Reas [2000a]), when the myoplasm is completely localized in the vegetal region (excitable stage) and the ascidian egg cell is perturbed by an increase of Ca++ concentration in the culture medium, the cell reacts by showing persistent mechanical waves of contraction which exist as long as the cell is perturbed. Experimentally we observed the production of a polar lobe located in the vegetal region and the change of the inclination of mitotic furrow, after the appearance of a myoplasmic spiral wave in the vegetal pole. So we suppose that the myoplasmic spiral wave is due to a Ca++ spiral wave, and the myoplasmic spiral wave then causes the changes in the shape of the cell (polar lobe, inclination of mitotic furrow, etc.). Moreover we give a simple geometrical description of a spiral wave.

  19. Analysis of unsteady wave processes in a rotating channel

    NASA Technical Reports Server (NTRS)

    Larosiliere, L. M.; Mawid, M.

    1993-01-01

    The impact of passage rotation on the gas dynamic wave processes is analyzed through a numerical simulation of ideal shock-tube flow in a closed rotating-channel. Initial conditions are prescribed by assuming homentropic solid-body rotation. Relevant parameters of the problem such as wheel Mach number, hub-to-tip radius ratio, length-to-tip radius ratio, diaphragm temperature ratio, and diaphragm pressure ratio are varied. The results suggest possible criteria for assessing the consequences of passage rotation on the wave processes, and they may therefore be applicable to pressure-exchange wave rotors. It is shown that for a fixed geometry and initial conditions, the contact interface acquires a distorted three-dimensional time-dependent orientation at non-zero wheel Mach numbers. At a fixed wheel Mach number, the level of distortion depends primarily on the density ratio across the interface as well as the hub-to-tip radius ratio. Rarefaction fronts, shocks, and contact interfaces are observed to propagate faster with increasing wheel Mach number.

  20. Analysis of unsteady wave processes in a rotating channel

    NASA Astrophysics Data System (ADS)

    Larosiliere, Louis M.; Mawid, M.

    1993-06-01

    The impact of passage rotation on the gas dynamic wave processes is analyzed through a numerical simulation of ideal shock-tube flow in a closed rotating-channel. Initial conditions are prescribed by assuming homentropic solid-body rotation. Relevant parameters of the problem such as wheel Mach number, hub-to-tip radius ratio, length-to-tip radius ratio, diaphragm temperature ratio, and diaphragm pressure ratio are varied. The results suggest possible criteria for assessing the consequences of passage rotation on the wave processes, and they may therefore be applicable to pressure-exchange wave rotors. It is shown that for a fixed geometry and initial conditions, the contact interface acquires a distorted three-dimensional time-dependent orientation at non-zero wheel Mach numbers. At a fixed wheel Mach number, the level of distortion depends primarily on the density ratio across the interface as well as the hub-to-tip radius ratio. Rarefaction fronts, shocks, and contact interfaces are observed to propagate faster with increasing wheel Mach number.

  1. Theoretical prediction of a rotating magnon wave packet in ferromagnets.

    PubMed

    Matsumoto, Ryo; Murakami, Shuichi

    2011-05-13

    We theoretically show that the magnon wave packet has a rotational motion in two ways: a self-rotation and a motion along the boundary of the sample (edge current). They are similar to the cyclotron motion of electrons, but unlike electrons the magnons have no charge and the rotation is not due to the Lorentz force. These rotational motions are caused by the Berry phase in momentum space from the magnon band structure. Furthermore, the rotational motion of the magnon gives an additional correction term to the magnon Hall effect. We also discuss the Berry curvature effect in the classical limit of long-wavelength magnetostatic spin waves having macroscopic coherence length.

  2. Extracorporeal shock wave treatment for chronic rotator cuff tendonitis (shoulder pain).

    PubMed

    Ho, C

    2007-01-01

    (1) Electrohydraulic, electromagnetic, or piezoelectric devices are used to translate energy into acoustic waves during extracorporeal shock wave treatment (ESWT) for chronic rotator cuff tendonitis (shoulder pain). The acoustic waves may help to accelerate the healing process of chronic rotator cuff tendonitis via an unknown mechanism. (2) ESWT, which is performed as an outpatient procedure, is intended to alleviate the pain due to chronic rotator cuff tendonitis. (3) Limited evidence from a German study indicates that the cost of ESWT for rotator cuff tendonitis is one-fifth to one-seventh the cost of surgical treatment, with longer recovery time and time off work in the surgical treatment group accounting for about two-thirds of the overall cost. (4) The evidence reviewed for this bulletin supports the use of high-energy ESWT for chronic calcific rotator cuff tendonitis, but not for non-calcific rotator cuff tendonitis. High-quality RCTs with larger sample sizes are needed to provide stronger evidence.

  3. Experimental observation of steady inertial wave turbulence in deep rotating flows

    NASA Astrophysics Data System (ADS)

    Yarom, Ehud; Sharon, Eran

    2015-11-01

    We present experimental evidence of inertial wave turbulence in deep rotating fluid. Experiments were performed in a rotating cylindrical water tank, where previous work showed statistics similar to 2D turbulence (specifically an inverse energy cascade). Using Fourier analysis of high resolution data in both space (3D) and time we show that most of the energy of a steady state flow is contained around the inertial wave dispersion relation. The nonlinear interaction between the waves is manifested by the widening of the time spectrum around the dispersion relation. We show that as the Rossby number increases so does the spectrum width, with a strong dependence on wave number. Our results suggest that in some parameters range, rotating turbulence velocity field can be represented as a field of interacting waves (wave turbulence). Such formalism may provide a better understanding of the flow statistics. This work was supported by the Israel Science Foundation, Grant No. 81/12.

  4. Lagrangian particle drift and surface deformation in a rotating wave on a free liquid surface

    NASA Astrophysics Data System (ADS)

    Fontana, Paul W.; Francois, Nicolas; Xia, Hua; Punzmann, Horst; Shats, Michael

    2017-11-01

    A nonlinear model of a rotating wave on the free surface of a liquid is presented. The flow is assumed to be inviscid and irrotational. The wave is constructed as a superposition of two perpendicular, monochromatic standing Stokes waves and is standing-wave-like, but with ``antinodes'' or cells consisting of rotating surface gradients of alternating polarity. Lagrangian fluid particle trajectories show a rotational drift about each cell in the direction of wave rotation, corresponding to a rotating Stokes drift. Each cell therefore has a circulating flow and localized angular momentum even though the Eulerian flow is irrotational. Meanwhile, the wave sets up a static displacement of the free surface, making a trough in each cell. This static surface gradient provides a centripetal force that may account for additional rotation seen in experiments.

  5. Efficiency of wave-driven rigid body rotation toroidal confinement

    NASA Astrophysics Data System (ADS)

    Rax, J. M.; Gueroult, R.; Fisch, N. J.

    2017-03-01

    The compensation of vertical drifts in toroidal magnetic fields through a wave-driven poloidal rotation is compared with compensation through the wave driven toroidal current generation to support the classical magnetic rotational transform. The advantages and drawbacks associated with the sustainment of a radial electric field are compared with those associated with the sustainment of a poloidal magnetic field both in terms of energy content and power dissipation. The energy content of a radial electric field is found to be smaller than the energy content of a poloidal magnetic field for a similar set of orbits. The wave driven radial electric field generation efficiency is similarly shown, at least in the limit of large aspect ratio, to be larger than the efficiency of wave-driven toroidal current generation.

  6. The Submillimeter-wave Rotational Spectra of Interstellar Molecules

    NASA Technical Reports Server (NTRS)

    Herbst, Eric; DeLucia, Frank C.; Butler, R. A. H.; Winnewisser, M.; Winnewisser, G.; Fuchs, U.; Groner, P.; Sastry, K. V. L. N.

    2002-01-01

    We discuss past and recent progress in our long-term laboratory program concerning the submillimeter-wave rotational spectroscopy of known and likely interstellar molecules, especially those associated with regions of high-mass star formation. Our program on the use of spectroscopy to study rotationally inelastic collisions of interstellar interest is also briefly mentioned.

  7. Nonlinear travelling waves in rotating Hagen–Poiseuille flow

    NASA Astrophysics Data System (ADS)

    Pier, Benoît; Govindarajan, Rama

    2018-03-01

    The dynamics of viscous flow through a rotating pipe is considered. Small-amplitude stability characteristics are obtained by linearizing the Navier–Stokes equations around the base flow and solving the resulting eigenvalue problems. For linearly unstable configurations, the dynamics leads to fully developed finite-amplitude perturbations that are computed by direct numerical simulations of the complete Navier–Stokes equations. By systematically investigating all linearly unstable combinations of streamwise wave number k and azimuthal mode number m, for streamwise Reynolds numbers {{Re}}z ≤slant 500 and rotational Reynolds numbers {{Re}}{{Ω }} ≤slant 500, the complete range of nonlinear travelling waves is obtained and the associated flow fields are characterized.

  8. Comparisons of characteristic timescales and approximate models for Brownian magnetic nanoparticle rotations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reeves, Daniel B., E-mail: dbr@Dartmouth.edu; Weaver, John B.

    2015-06-21

    Magnetic nanoparticles are promising tools for a host of therapeutic and diagnostic medical applications. The dynamics of rotating magnetic nanoparticles in applied magnetic fields depend strongly on the type and strength of the field applied. There are two possible rotation mechanisms and the decision for the dominant mechanism is often made by comparing the equilibrium relaxation times. This is a problem when particles are driven with high-amplitude fields because they are not necessarily at equilibrium at all. Instead, it is more appropriate to consider the “characteristic timescales” that arise in various applied fields. Approximate forms for the characteristic time ofmore » Brownian particle rotations do exist and we show agreement between several analytical and phenomenological-fit models to simulated data from a stochastic Langevin equation approach. We also compare several approximate models with solutions of the Fokker-Planck equation to determine their range of validity for general fields and relaxation times. The effective field model is an excellent approximation, while the linear response solution is only useful for very low fields and frequencies for realistic Brownian particle rotations.« less

  9. A diffusion approximation for ocean wave scatterings by randomly distributed ice floes

    NASA Astrophysics Data System (ADS)

    Zhao, Xin; Shen, Hayley

    2016-11-01

    This study presents a continuum approach using a diffusion approximation method to solve the scattering of ocean waves by randomly distributed ice floes. In order to model both strong and weak scattering, the proposed method decomposes the wave action density function into two parts: the transmitted part and the scattered part. For a given wave direction, the transmitted part of the wave action density is defined as the part of wave action density in the same direction before the scattering; and the scattered part is a first order Fourier series approximation for the directional spreading caused by scattering. An additional approximation is also adopted for simplification, in which the net directional redistribution of wave action by a single scatterer is assumed to be the reflected wave action of a normally incident wave into a semi-infinite ice cover. Other required input includes the mean shear modulus, diameter and thickness of ice floes, and the ice concentration. The directional spreading of wave energy from the diffusion approximation is found to be in reasonable agreement with the previous solution using the Boltzmann equation. The diffusion model provides an alternative method to implement wave scattering into an operational wave model.

  10. Evolution of a hybrid micro-macro entangled state of the qubit-oscillator system via the generalized rotating wave approximation

    NASA Astrophysics Data System (ADS)

    Chakrabarti, R.; Yogesh, V.

    2016-04-01

    We study the evolution of the hybrid entangled states in a bipartite (ultra) strongly coupled qubit-oscillator system. Using the generalized rotating wave approximation the reduced density matrices of the qubit and the oscillator are obtained. The reduced density matrix of the oscillator yields the phase space quasi probability distributions such as the diagonal P-representation, the Wigner W-distribution and the Husimi Q-function. In the strong coupling regime the Q-function evolves to uniformly separated macroscopically distinct Gaussian peaks representing ‘kitten’ states at certain specified times that depend on multiple time scales present in the interacting system. The ultrastrong coupling strength of the interaction triggers appearance of a large number of modes that quickly develop a randomization of their phase relationships. A stochastic averaging of the dynamical quantities sets in, and leads to the decoherence of the system. The delocalization in the phase space of the oscillator is studied by using the Wehrl entropy. The negativity of the W-distribution reflects the departure of the oscillator from the classical states, and allows us to study the underlying differences between various information-theoretic measures such as the Wehrl entropy and the Wigner entropy. Other features of nonclassicality such as the existence of the squeezed states and appearance of negative values of the Mandel parameter are realized during the course of evolution of the bipartite system. In the parametric regime studied here these properties do not survive in the time-averaged limit.

  11. Rotationally and vibrationally inelastic scattering in the rotational IOS approximation. Ultrasimple calculation of total (differential, integral, and transport) cross sections for nonspherical molecules

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, G.A.; Pack, R.T

    1978-02-15

    A simple, direct derivation of the rotational infinite order sudden (IOS) approximation in molecular scattering theory is given. Connections between simple scattering amplitude formulas, choice of average partial wave parameter, and magnetic transitions are reviewed. Simple procedures for calculating cross sections for specific transitions are discussed and many older model formulas are given clear derivations. Total (summed over rotation) differential, integral, and transport cross sections, useful in the analysis of many experiments involving nonspherical molecules, are shown to be exceedingly simple: They are just averages over the potential angle of cross sections calculated using simple structureless spherical particle formulas andmore » programs. In the case of vibrationally inelastic scattering, the IOSA, without further approximation, provides a well-defined way to get fully three dimensional cross sections from calculations no more difficult than collinear calculations. Integral, differential, viscosity, and diffusion cross sections for He-CO/sub 2/ obtained from the IOSA and a realistic intermolecular potential are calculated as an example and compared with experiment. Agreement is good for the complete potential but poor when only its spherical part is used, so that one should never attempt to treat this system with a spherical model. The simplicity and accuracy of the IOSA make it a viable method for routine analysis of experiments involving collisions of nonspherical molecules.« less

  12. Rotating magnetic shallow water waves and instabilities in a sphere

    NASA Astrophysics Data System (ADS)

    Márquez-Artavia, X.; Jones, C. A.; Tobias, S. M.

    2017-07-01

    Waves in a thin layer on a rotating sphere are studied. The effect of a toroidal magnetic field is considered, using the shallow water ideal MHD equations. The work is motivated by suggestions that there is a stably stratified layer below the Earth's core mantle boundary, and the existence of stable layers in stellar tachoclines. With an azimuthal background field known as the Malkus field, ?, ? being the co-latitude, a non-diffusive instability is found with azimuthal wavenumber ?. A necessary condition for instability is that the Alfvén speed exceeds ? where ? is the rotation rate and ? the sphere radius. Magneto-inertial gravity waves propagating westward and eastward occur, and become equatorially trapped when the field is strong. Magneto-Kelvin waves propagate eastward at low field strength, but a new westward propagating Kelvin wave is found when the field is strong. Fast magnetic Rossby waves travel westward, whilst the slow magnetic Rossby waves generally travel eastward, except for some ? modes at large field strength. An exceptional very slow westward ? magnetic Rossby wave mode occurs at all field strengths. The current-driven instability occurs for ? when the slow and fast magnetic Rossby waves interact. With strong field the magnetic Rossby waves become trapped at the pole. An asymptotic analysis giving the wave speed and wave form in terms of elementary functions is possible both in polar trapped and equatorially trapped cases.

  13. Absorption of inertia-gravity waves in vertically sheared rotating stratified flows

    NASA Astrophysics Data System (ADS)

    Millet, C.; Lott, F.

    2012-12-01

    It is well established that gravity waves have a substantial role on the large-scale atmospheric circulation, particularly in the middle atmosphere. In the present work, we re-examine the reflection and transmission of gravity waves through a critical layer surrounded by two inertial levels for the case of a constant vertically sheared flow. In this configuration, the vertical structure of the disturbance can be described as quasi-geostrophic from the critical layer up to the inertial levels, at which the Doppler-shifted frequency is equal to the Coriolis parameter. Near and beyond these levels, the balanced approximations do not apply and there is a transition from the quasi-geostrophic solution to propagating gravity waves. The three-dimensional disturbance solution is obtained analytically using both an exact method, in terms of hypergeometric functions, and a WKB approximation valid for large Richardson numbers; the latter includes an exponentially small term which captures the radiation feedback in the region between the inertial levels. We first focused on the homogeneous part of the disturbance equations, under the assumption of an unbounded domain. In contrast with past studies which show that there is a finite reflection and did not analyze the transmission (Yamanaka and Tanaka, 1984), we find that the reflection coefficient is too small to be significant and that the transmission coefficient is exactly like in the much simpler non-rotating case analyzed by Booker and Bretherton (1966). Our theoretical predictions are found to be in very good agreement with those obtained by numerically integrating the complete hydrostatic-Boussinesq equations with a small Rayleigh damping. The discrepancies between our results and those in Yamanaka and Tanaka (1984) are related to the fact that the solutions are given in term of multivalued functions and the values of the reflection and transmission coefficients are exponentially small, e.g. quite difficult to cross check

  14. Liberation of a pinned spiral wave by a rotating electric pulse

    NASA Astrophysics Data System (ADS)

    Chen, Jiang-Xing; Peng, Liang; Ma, Jun; Ying, He-Ping

    2014-08-01

    Spiral waves may be pinned to anatomical heterogeneities in the cardiac tissue, which leads to monomorphic ventricular tachycardia. Wave emission from heterogeneities (WEH) induced by electric pulses in one direction (EP) is a promising method for liberating such waves by using heterogeneities as internal virtual pacing sites. Here, based on the WEH effect, a new mechanism of liberation by means of a rotating electric pulse (REP) is proposed in a generic model of excitable media. Compared with the EP, the REP has the advantage of opening wider time window to liberate pinned spiral. The influences of rotating direction and frequency of the REP, and the radius of the obstacles on this new mechanism are studied. We believe this strategy may improve manipulations with pinned spiral waves in heart experiments.

  15. Formulation of the rotational transformation of wave fields and their application to digital holography.

    PubMed

    Matsushima, Kyoji

    2008-07-01

    Rotational transformation based on coordinate rotation in Fourier space is a useful technique for simulating wave field propagation between nonparallel planes. This technique is characterized by fast computation because the transformation only requires executing a fast Fourier transform twice and a single interpolation. It is proved that the formula of the rotational transformation mathematically satisfies the Helmholtz equation. Moreover, to verify the formulation and its usefulness in wave optics, it is also demonstrated that the transformation makes it possible to reconstruct an image on arbitrarily tilted planes from a wave field captured experimentally by using digital holography.

  16. APPROXIMATION OF ROTATIONAL STRENGTHS FROM MOLAR ROTATION DATA AND GENERATION OF ROTATORY DISPERSION CURVES FOR D-CAMPHOR-10-SULFONATE

    PubMed Central

    Urry, Dan W.

    1969-01-01

    Starting with the expression for optical rotatory dispersion in the absorption region that was arrived at by Condon, two series were considered for the purpose of achieving the experimentally observed, steeper wavelength dependence in the absorption region while retaining the established 1/λ2 law in regions removed from absorption. The first two terms of one series in which the second term exhibits a 1/λ6 wavelength dependence were found to calculate satisfactorily the optical rotatory dispersion curve of d-camphor-10-sulfonate from 400 mμ to 190 mμ when only three bands were considered. Evaluated at the extrema, the two-term expression can be approximated by a simple equation which allows calculation of the rotational strength of a nonoverlapping band by using only the wavelength and molar rotation of the extrema and the index of refraction of the solution. The rotational strengths calculated from optical rotatory dispersion data in this manner closely agree with those calculated from corresponding circular dichroism data. Thus when position and magnitude of rotatory dispersion extrema alone are reported for carbonyls, it is suggested that such published data may be converted to approximate rotational strengths. PMID:5257123

  17. Approximate Dispersion Relations for Waves on Arbitrary Shear Flows

    NASA Astrophysics Data System (ADS)

    Ellingsen, S. À.; Li, Y.

    2017-12-01

    An approximate dispersion relation is derived and presented for linear surface waves atop a shear current whose magnitude and direction can vary arbitrarily with depth. The approximation, derived to first order of deviation from potential flow, is shown to produce good approximations at all wavelengths for a wide range of naturally occuring shear flows as well as widely used model flows. The relation reduces in many cases to a 3-D generalization of the much used approximation by Skop (1987), developed further by Kirby and Chen (1989), but is shown to be more robust, succeeding in situations where the Kirby and Chen model fails. The two approximations incur the same numerical cost and difficulty. While the Kirby and Chen approximation is excellent for a wide range of currents, the exact criteria for its applicability have not been known. We explain the apparently serendipitous success of the latter and derive proper conditions of applicability for both approximate dispersion relations. Our new model has a greater range of applicability. A second order approximation is also derived. It greatly improves accuracy, which is shown to be important in difficult cases. It has an advantage over the corresponding second-order expression proposed by Kirby and Chen that its criterion of accuracy is explicitly known, which is not currently the case for the latter to our knowledge. Our second-order term is also arguably significantly simpler to implement, and more physically transparent, than its sibling due to Kirby and Chen.Plain Language SummaryIn order to answer key questions such as how the ocean surface affects the climate, erodes the coastline and transports nutrients, we must understand how <span class="hlt">waves</span> move. This is not so easy when depth varying currents are present, as they often are in coastal waters. We have developed a modeling tool for accurately predicting <span class="hlt">wave</span> properties in such situations, ready for use, for example, in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24i2513O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24i2513O"><span>Particle orbits in a force-balanced, <span class="hlt">wave</span>-driven, <span class="hlt">rotating</span> torus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ochs, I. E.; Fisch, N. J.</p> <p>2017-09-01</p> <p>A <span class="hlt">wave</span>-driven <span class="hlt">rotating</span> torus is a recently proposed fusion concept where the <span class="hlt">rotational</span> transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-<span class="hlt">wave</span>-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in this desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of <span class="hlt">rotational</span> transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23521253','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23521253"><span>Tidal <span class="hlt">waves</span> in 102Pd: a <span class="hlt">rotating</span> condensate of multiple d bosons.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ayangeakaa, A D; Garg, U; Caprio, M A; Carpenter, M P; Ghugre, S S; Janssens, R V F; Kondev, F G; Matta, J T; Mukhopadhyay, S; Patel, D; Seweryniak, D; Sun, J; Zhu, S; Frauendorf, S</p> <p>2013-03-08</p> <p>Low-lying collective excitations in even-even vibrational and transitional nuclei may be described semiclassically as quadrupole running <span class="hlt">waves</span> on the surface of the nucleus ("tidal <span class="hlt">waves</span>"), and the observed vibrational-<span class="hlt">rotational</span> behavior can be thought of as resulting from a <span class="hlt">rotating</span> condensate of interacting d bosons. These concepts have been investigated by measuring lifetimes of the levels in the yrast band of the (102)Pd nucleus with the Doppler shift attenuation method. The extracted B(E2) reduced transition probabilities for the yrast band display a monotonic increase with spin, in agreement with the interpretation based on <span class="hlt">rotation</span>-induced condensation of aligned d bosons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDL14004F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDL14004F"><span><span class="hlt">Wave</span>-front propagation of rinsing flows on <span class="hlt">rotating</span> semiconductor wafers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frostad, John M.; Ylitalo, Andy; Walls, Daniel J.; Mui, David S. L.; Fuller, Gerald G.</p> <p>2016-11-01</p> <p>The semiconductor manufacturing industry is migrating to a cleaning technology that involves dispersing cleaning solutions onto a <span class="hlt">rotating</span> wafer, similar to spin-coating. Advantages include a more continuous overall fabrication process, lower particle level, no cross contamination from the back side of a wafer, and less usage of harsh chemicals for a lower environmental impact. Rapid <span class="hlt">rotation</span> of the wafer during rinsing can be more effective, but centrifugal forces can pull spiral-like ribbons of liquid radially outward from the advancing <span class="hlt">wave</span>-front where particles can build up, causing higher instances of device failure at these locations. A better understanding of the rinsing flow is essential for reducing yield losses while taking advantage of the benefits of <span class="hlt">rotation</span>. In the present work, high-speed video and image processing are used to study the dynamics of the advancing <span class="hlt">wave</span>-front from an impinging jet on a <span class="hlt">rotating</span> substrate. The flow-rate and <span class="hlt">rotation</span>-speed are varied for substrates coated with a thin layer of a second liquid that has a different surface tension than the jet liquid. The difference in surface tension of the two fluids gives rise to Marangoni stresses at the interface that have a significant impact on the rinsing process, despite the extremely short time-scales involved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1355669-perpendicular-momentum-input-lower-hybrid-waves-its-influence-driving-plasma-rotation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1355669-perpendicular-momentum-input-lower-hybrid-waves-its-influence-driving-plasma-rotation"><span>Perpendicular momentum input of lower hybrid <span class="hlt">waves</span> and its influence on driving plasma <span class="hlt">rotation</span>.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Guan, Xiaoyin</p> <p></p> <p>The mechanism of perpendicular momentum input of lower hybrid <span class="hlt">waves</span> and its influence on plasma <span class="hlt">rotation</span> are studied. Discussion for parallel momentum input of lower hybrid <span class="hlt">waves</span> is presented for comparison. It is found out that both toroidal and poloidal projections of perpendicular momentum input of lower hybrid <span class="hlt">waves</span> are stronger than those of parallel momentum input. The perpendicular momentum input of lower hybrid <span class="hlt">waves</span> therefore plays a dominant role in forcing the changes of <span class="hlt">rotation</span> velocity observed during lower hybrid current drive. Lower hybrid <span class="hlt">waves</span> convert perpendicular momentum carried by the <span class="hlt">waves</span> into the momentum of dc electromagnetic fieldmore » by inducing a resonant-electron flow across flux surfaces therefore charge separation and a radial dc electric field. The dc field releases its momentum into plasma through the Lorentz force acting on the radial return current driven by the radial electric field. Plasma is spun up by the Lorentz force. An improved quasilinear theory with gyro-phase dependent distribution function is developed to calculate the radial flux of resonant electrons. <span class="hlt">Rotations</span> are determined by a set of fluid equations for bulk electrons and ions, which are solved numerically by applying a finite-difference method. Analytical expressions for toroidal and poloidal <span class="hlt">rotations</span> are derived using the same hydrodynamic model.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OptCo.413..136H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OptCo.413..136H"><span>Focusing optical <span class="hlt">waves</span> with a <span class="hlt">rotationally</span> symmetric sharp-edge aperture</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Yanwen; Fu, Shenhe; Li, Zhen; Yin, Hao; Zhou, Jianying; Chen, Zhenqiang</p> <p>2018-04-01</p> <p>While there has been various kinds of patterned structures proposed for <span class="hlt">wave</span> focusing, these patterned structures usually involve complicated lithographic techniques since the element size of the patterned structures should be precisely controlled in microscale or even nanoscale. Here we propose a new and straightforward method for focusing an optical plane <span class="hlt">wave</span> in free space with a <span class="hlt">rotationally</span> symmetric sharp-edge aperture. The focusing phenomenon of <span class="hlt">wave</span> is realized by superposition of a portion of the higher-order symmetric plane <span class="hlt">waves</span> generated from the sharp edges of the apertures, in contrast to previously focusing techniques which usually depend on a curved phase. We demonstrate both experimentally and theoretically the focusing effect with a series of apertures having different <span class="hlt">rotational</span> symmetry, and find that the intensity of the hotspots could be controlled by the symmetric strength of the sharp-edge apertures. The presented results would advance the conventional wisdom that light would diffract in all directions and become expanding when it propagates through an aperture. The proposed method is easy to be processed, and might open potential applications in interferometry, image, and superresolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011IJC....84..293A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011IJC....84..293A"><span>Neural <span class="hlt">rotational</span> speed control for <span class="hlt">wave</span> energy converters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Amundarain, M.; Alberdi, M.; Garrido, A. J.; Garrido, I.</p> <p>2011-02-01</p> <p>Among the benefits arising from an increasing use of renewable energy are: enhanced security of energy supply, stimulation of economic growth, job creation and protection of the environment. In this context, this study analyses the performance of an oscillating water column device for <span class="hlt">wave</span> energy conversion in function of the stalling behaviour in Wells turbines, one of the most widely used turbines in <span class="hlt">wave</span> energy plants. For this purpose, a model of neural <span class="hlt">rotational</span> speed control system is presented, simulated and implemented. This scheme is employed to appropriately adapt the speed of the doubly-fed induction generator coupled to the turbine according to the pressure drop entry, so as to avoid the undesired stalling behaviour. It is demonstrated that the proposed neural <span class="hlt">rotational</span> speed control design adequately matches the desired relationship between the slip of the doubly-fed induction generator and the pressure drop input, improving the power generated by the turbine generator module.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS.955a2015Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS.955a2015Z"><span>Nonlinear Interaction of <span class="hlt">Waves</span> in <span class="hlt">Rotating</span> Spherical Layers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhilenko, D.; Krivonosova, O.; Gritsevich, M.</p> <p>2018-01-01</p> <p>Flows of a viscous incompressible fluid in a spherical layer that are due to <span class="hlt">rotational</span> oscillations of its inner boundary at two frequencies with respect to the state of rest are numerically studied. It is found that an increase in the amplitude of oscillations of the boundary at the higher frequency can result in a significant enhancement of the low-frequency mode in a flow near the outer boundary. The direction of propagation of the low-frequency <span class="hlt">wave</span> changes from radial to meridional, whereas the high-frequency <span class="hlt">wave</span> propagates in the radial direction in a limited inner region of the spherical layer. The role of the meridional circulation in the energy exchange between spaced <span class="hlt">waves</span> is demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1430519-particle-orbits-force-balanced-wave-driven-rotating-torus','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1430519-particle-orbits-force-balanced-wave-driven-rotating-torus"><span>Particle orbits in a force-balanced, <span class="hlt">wave</span>-driven, <span class="hlt">rotating</span> torus</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ochs, I. E.; Fisch, N. J.</p> <p>2017-09-01</p> <p>A <span class="hlt">wave</span>-driven <span class="hlt">rotating</span> torus is a recently proposed fusion concept where the <span class="hlt">rotational</span> transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-<span class="hlt">wave</span>-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in thismore » desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of <span class="hlt">rotational</span> transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1430519-particle-orbits-force-balanced-wave-driven-rotating-torus','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1430519-particle-orbits-force-balanced-wave-driven-rotating-torus"><span>Particle orbits in a force-balanced, <span class="hlt">wave</span>-driven, <span class="hlt">rotating</span> torus</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ochs, I. E.; Fisch, N. J.</p> <p></p> <p>A <span class="hlt">wave</span>-driven <span class="hlt">rotating</span> torus is a recently proposed fusion concept where the <span class="hlt">rotational</span> transform is provided by the E × B drift resulting from a minor radial electric field. This field can be produced, for instance, by the RF-<span class="hlt">wave</span>-mediated extraction of fusion-born alpha particles. In this paper, we discuss how macroscopic force balance, i.e., balance of the thermal hoop force, can be achieved in such a device. We show that this requires the inclusion of a small plasma current and vertical magnetic field and identify the desirable reactor regime through free energy considerations. We then analyze particle orbits in thismore » desirable regime, identifying velocity-space anisotropies in trapped (banana) orbits, resulting from the cancellation of <span class="hlt">rotational</span> transforms due to the radial electric and poloidal magnetic fields. The potential neoclassical effects of these orbits on the perpendicular conductivity, current drive, and transport are discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1300866','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1300866"><span>Scroll <span class="hlt">wave</span> dynamics in a three-dimensional cardiac tissue model: roles of restitution, thickness, and fiber <span class="hlt">rotation</span>.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Qu, Z; Kil, J; Xie, F; Garfinkel, A; Weiss, J N</p> <p>2000-01-01</p> <p>Scroll <span class="hlt">wave</span> (vortex) breakup is hypothesized to underlie ventricular fibrillation, the leading cause of sudden cardiac death. We simulated scroll <span class="hlt">wave</span> behaviors in a three-dimensional cardiac tissue model, using phase I of the Luo-Rudy (LR1) action potential model. The effects of action potential duration (APD) restitution, tissue thickness, filament twist, and fiber <span class="hlt">rotation</span> were studied. We found that APD restitution is the major determinant of scroll <span class="hlt">wave</span> behavior and that instabilities arising from APD restitution are the main determinants of scroll <span class="hlt">wave</span> breakup in this cardiac model. We did not see a "thickness-induced instability" in the LR1 model, but a minimum thickness is required for scroll breakup in the presence of fiber <span class="hlt">rotation</span>. The major effect of fiber <span class="hlt">rotation</span> is to maintain twist in a scroll <span class="hlt">wave</span>, promoting filament bending and thus scroll breakup. In addition, fiber <span class="hlt">rotation</span> induces curvature in the scroll <span class="hlt">wave</span>, which weakens conduction and further facilitates <span class="hlt">wave</span> break. PMID:10827961</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.938a2031K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.938a2031K"><span>Quantum scattering beyond the plane-<span class="hlt">wave</span> <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karlovets, Dmitry</p> <p>2017-12-01</p> <p>While a plane-<span class="hlt">wave</span> <span class="hlt">approximation</span> in high-energy physics works well in a majority of practical cases, it becomes inapplicable for scattering of the vortex particles carrying orbital angular momentum, of Airy beams, of the so-called Schrödinger cat states, and their generalizations. Such quantum states of photons, electrons and neutrons have been generated experimentally in recent years, opening up new perspectives in quantum optics, electron microscopy, particle physics, and so forth. Here we discuss the non-plane-<span class="hlt">wave</span> effects in scattering brought about by the novel quantum numbers of these <span class="hlt">wave</span> packets. For the well-focused electrons of intermediate energies, already available at electron microscopes, the corresponding contribution can surpass that of the radiative corrections. Moreover, collisions of the cat-like superpositions of such focused beams with atoms allow one to probe effects of the quantum interference, which have never played any role in particle scattering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993cfd..proc..675H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993cfd..proc..675H"><span>Excitation and propagation of nonlinear <span class="hlt">waves</span> in a <span class="hlt">rotating</span> fluid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hanazaki, Hideshi</p> <p>1993-09-01</p> <p>A numerical study of the nonlinear <span class="hlt">waves</span> excited in an axisymmetric <span class="hlt">rotating</span> flow through a circular tube is described. The <span class="hlt">waves</span> are excited by either an undulation of the tube wall or an obstacle on the axis of the tube. The results are compared with the weakly nonlinear theory (forced KdV equation). The computations are done when the upstream swirling velocity is that of Burgers' vortex type. The flow behaves like the solution of the forced KdV equation, and the upstream advancing of the <span class="hlt">waves</span> appear even when the flow is critical or slightly supercritical to the fastest inertial <span class="hlt">wave</span> mode.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29507180','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29507180"><span>Spectral analysis of localized <span class="hlt">rotating</span> <span class="hlt">waves</span> in parabolic systems.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Beyn, Wolf-Jürgen; Otten, Denny</p> <p>2018-04-13</p> <p>In this paper, we study the spectra and Fredholm properties of Ornstein-Uhlenbeck operators [Formula: see text]where [Formula: see text] is the profile of a <span class="hlt">rotating</span> <span class="hlt">wave</span> satisfying [Formula: see text] as [Formula: see text], the map [Formula: see text] is smooth and the matrix [Formula: see text] has eigenvalues with positive real parts and commutes with the limit matrix [Formula: see text] The matrix [Formula: see text] is assumed to be skew-symmetric with eigenvalues (λ 1 ,…,λ d )=(±i σ 1 ,…,±i σ k ,0,…,0). The spectra of these linearized operators are crucial for the nonlinear stability of <span class="hlt">rotating</span> <span class="hlt">waves</span> in reaction-diffusion systems. We prove under appropriate conditions that every [Formula: see text] satisfying the dispersion relation [Formula: see text]belongs to the essential spectrum [Formula: see text] in L p For values Re λ to the right of the spectral bound for [Formula: see text], we show that the operator [Formula: see text] is Fredholm of index 0, solve the identification problem for the adjoint operator [Formula: see text] and formulate the Fredholm alternative. Moreover, we show that the set [Formula: see text]belongs to the point spectrum [Formula: see text] in L p We determine the associated eigenfunctions and show that they decay exponentially in space. As an application, we analyse spinning soliton solutions which occur in the Ginzburg-Landau equation and compute their numerical spectra as well as associated eigenfunctions. Our results form the basis for investigating the nonlinear stability of <span class="hlt">rotating</span> <span class="hlt">waves</span> in higher space dimensions and truncations to bounded domains. This article is part of the themed issue 'Stability of nonlinear <span class="hlt">waves</span> and patterns and related topics'. © 2018 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018CompM.tmp..266B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018CompM.tmp..266B"><span>A projection-based model reduction strategy for the <span class="hlt">wave</span> and vibration analysis of <span class="hlt">rotating</span> periodic structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beli, D.; Mencik, J.-M.; Silva, P. B.; Arruda, J. R. F.</p> <p>2018-05-01</p> <p>The <span class="hlt">wave</span> finite element method has proved to be an efficient and accurate numerical tool to perform the free and forced vibration analysis of linear reciprocal periodic structures, i.e. those conforming to symmetrical <span class="hlt">wave</span> fields. In this paper, its use is extended to the analysis of <span class="hlt">rotating</span> periodic structures, which, due to the gyroscopic effect, exhibit asymmetric <span class="hlt">wave</span> propagation. A projection-based strategy which uses reduced symplectic <span class="hlt">wave</span> basis is employed, which provides a well-conditioned eigenproblem for computing <span class="hlt">waves</span> in <span class="hlt">rotating</span> periodic structures. The proposed formulation is applied to the free and forced response analysis of homogeneous, multi-layered and phononic ring structures. In all test cases, the following features are highlighted: well-conditioned dispersion diagrams, good accuracy, and low computational time. The proposed strategy is particularly convenient in the simulation of <span class="hlt">rotating</span> structures when parametric analysis for several <span class="hlt">rotational</span> speeds is usually required, e.g. for calculating Campbell diagrams. This provides an efficient and flexible framework for the analysis of rotordynamic problems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018IJBC...2850054L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018IJBC...2850054L"><span>Solitary <span class="hlt">Waves</span>, Periodic Peakons and Pseudo-Peakons of the Nonlinear Acoustic <span class="hlt">Wave</span> Model in <span class="hlt">Rotating</span> Magnetized Plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jibin</p> <p></p> <p>The dynamical model of the nonlinear acoustic <span class="hlt">wave</span> in <span class="hlt">rotating</span> magnetized plasma is governed by a partial differential equation system. Its traveling system is a singular traveling <span class="hlt">wave</span> system of first class depending on two parameters. By using the bifurcation theory and method of dynamical systems and the theory of singular traveling <span class="hlt">wave</span> systems, in this paper, we show that there exist parameter groups such that this singular system has pseudo-peakons, periodic peakons and compactons as well as different solitary <span class="hlt">wave</span> solutions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760004589','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760004589"><span>Comparison of techniques for <span class="hlt">approximating</span> ocean bottom topography in a <span class="hlt">wave</span>-refraction computer model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poole, L. R.</p> <p>1975-01-01</p> <p>A study of the effects of using different methods for <span class="hlt">approximating</span> bottom topography in a <span class="hlt">wave</span>-refraction computer model was conducted. <span class="hlt">Approximation</span> techniques involving quadratic least squares, cubic least squares, and constrained bicubic polynomial interpolation were compared for computed <span class="hlt">wave</span> patterns and parameters in the region of Saco Bay, Maine. Although substantial local differences can be attributed to use of the different <span class="hlt">approximation</span> techniques, results indicated that overall computed <span class="hlt">wave</span> patterns and parameter distributions were quite similar.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810014461','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810014461"><span>Far-infrared <span class="hlt">rotational</span> emission by carbon monoxide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mckee, C. F.; Storey, J. W. V.; Watson, D. M.; Green, S.</p> <p>1981-01-01</p> <p>Accurate theoretical collisional excitation rates are used to determine the emissivities of CO <span class="hlt">rotational</span> lines 10 to the 4th power/cu cm n(H2), 100 K T 2000 K, and J 50. An <span class="hlt">approximate</span> analytic expression for the emissitivities which is valid over most of this region is obtained. Population inversions in the lower <span class="hlt">rotational</span> levels occur for densities n(H2) <span class="hlt">approximately</span> 10 (to the 3rd to 5th power)/cu cm and temperatures T <span class="hlt">approximately</span> 50 K. Interstellar shocks observed edge on are a potential source of millimeter <span class="hlt">wave</span> CO maser emission. The CO <span class="hlt">rotational</span> cooling function suggested by Hollenbach and McKee (1979) is verified, and accurate numerical values given. Application of these results to other linear molecules should be straightforward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22482458-inertia-gravity-wave-radiation-from-merging-two-co-rotating-vortices-plane-shallow-water-system','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22482458-inertia-gravity-wave-radiation-from-merging-two-co-rotating-vortices-plane-shallow-water-system"><span>Inertia-gravity <span class="hlt">wave</span> radiation from the merging of two co-<span class="hlt">rotating</span> vortices in the f-plane shallow water system</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Sugimoto, Norihiko, E-mail: nori@phys-h.keio.ac.jp</p> <p></p> <p>Inertia-gravity <span class="hlt">wave</span> radiation from the merging of two co-<span class="hlt">rotating</span> vortices is investigated numerically in a <span class="hlt">rotating</span> shallow water system in order to focus on cyclone–anticyclone asymmetry at different values of the Rossby number (Ro). A numerical study is conducted on a model using a spectral method in an unbounded domain to estimate the gravity <span class="hlt">wave</span> flux with high accuracy. Continuous gravity <span class="hlt">wave</span> radiation is observed in three stages of vortical flows: co-<span class="hlt">rotating</span> of the vortices, merging of the vortices, and unsteady motion of the merged vortex. A cyclone–anticyclone asymmetry appears at all stages at smaller Ro (≤20). Gravity <span class="hlt">waves</span> frommore » anticyclones are always larger than those from cyclones and have a local maximum at smaller Ro (∼2) compared with that for an idealized case of a co-<span class="hlt">rotating</span> vortex pair with a constant <span class="hlt">rotation</span> rate. The source originating in the Coriolis acceleration has a key role in cyclone–anticyclone asymmetry in gravity <span class="hlt">waves</span>. An additional important factor is that at later stages, the merged axisymmetric anticyclone <span class="hlt">rotates</span> faster than the elliptical cyclone due to the effect of the Rossby deformation radius, since a <span class="hlt">rotation</span> rate higher than the inertial cutoff frequency is required to radiate gravity <span class="hlt">waves</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20719063','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20719063"><span>Effective suppression of stray light in <span class="hlt">rotational</span> coherent anti-stokes Raman spectroscopy using an angle-tuned short-<span class="hlt">wave</span>-pass filter.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bohlin, Alexis; Bengtsson, Per-Erik</p> <p>2010-08-01</p> <p>Stray light interference is a common problem in spontaneous <span class="hlt">rotational</span> Raman spectroscopy and <span class="hlt">rotational</span> coherent anti-Stokes Raman spectropscopy (CARS). The reason is that the detected spectrum appears in the spectral vicinity of the probe beam wavelength, and stray light at this wavelength from optics and surfaces is hard to suppress. In this Note, efficient suppression of stray light is demonstrated for <span class="hlt">rotational</span> CARS measurements using a commercially available short-<span class="hlt">wave</span>-pass filter. By angle-tuning this filter with a specified cut-off wavelength at 561 nm, the cut-off wavelength could be tuned to a desired spectral position so that more than 80% transmission is achieved as close as 15 cm(-1) (<span class="hlt">approximately</span> 0.4 nm) from the probe beam wavelength of 532.0 nm, while the intensity at this wavelength is suppressed by two orders of magnitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS11C1649G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS11C1649G"><span>The effect of <span class="hlt">rotation</span> on shoaling of large amplitude internal solitary <span class="hlt">waves</span> in the northern South China Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guo, C.; Vlasenko, V.</p> <p>2012-12-01</p> <p>The propagation of large amplitude internal solitary <span class="hlt">waves</span> (ISWs) in the northern South China Sea (SCS) is simulated using the fully nonlinear, nonhydrostatic MIT general circulation model (MITgcm). Special attention is paid to the effects of <span class="hlt">rotation</span> and the shoaling three-dimensional topography. It is found that for the conditions of the northern SCS, a propagating ISW continuously loses its energy under the action of <span class="hlt">rotation</span> by shedding inertia-gravity <span class="hlt">waves</span> backwards, which further become steepened and form a new ISW. Such a decay-reemergence process repeats itself in a similar way as discussed by Helfrich (2007) with the only difference that, instead of the formation of a final localized <span class="hlt">wave</span> packet, the frontal <span class="hlt">waves</span> constantly attenuate by repeatedly shedding inertia-gravity <span class="hlt">waves</span> backwards. Under the action of <span class="hlt">rotation</span> and variable topography, the shoaling ISWs attenuate severely and disintegrate after passing through the continental slope. <span class="hlt">Wave</span> polarity starts to reverse at the depth of about 130 m, which is consistent with the prediction of weakly nonlinear theories. It is also found that the <span class="hlt">rotational</span> effects are more pronounced in combination with the topographic effects in the three-dimensional realistic context. Discrepancies between the <span class="hlt">wave</span> profiles obtained with and without <span class="hlt">rotation</span> are small in the deep part of the ocean but eventually turn out to be significant when going upon the shelf, addressing the crucial roles played by the <span class="hlt">rotation</span> in the northern SCS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750026112&hterms=1057&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3D%2526%25231057','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750026112&hterms=1057&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3D%2526%25231057"><span><span class="hlt">Rotational</span>-vibrational coupling in the theory of electron-molecule scattering</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Temkin, A.; Sullivan, E. C.</p> <p>1974-01-01</p> <p>The adiabatic-nuclei <span class="hlt">approximation</span> of vibrational-<span class="hlt">rotational</span> excitation of homonuclear diatomic molecules can be simply augmented to describe the vibrational-<span class="hlt">rotational</span> coupling by including the dependence of the vibrational <span class="hlt">wave</span> function on j. Appropriate formulas are given, and the theory, is applied to e-H2 excitation, whereby it is shown that deviations from the simple Born-Oppenheimer <span class="hlt">approximation</span> measured by Wong and Schultz can be explained. More important, it can be seen that the inclusion of the j-dependent centrifugal term is essential for transitions involving high-<span class="hlt">rotational</span> quantum numbers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22413087-fast-strain-wave-induced-magnetization-changes-long-cobalt-bars-domain-motion-versus-coherent-rotation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22413087-fast-strain-wave-induced-magnetization-changes-long-cobalt-bars-domain-motion-versus-coherent-rotation"><span>Fast strain <span class="hlt">wave</span> induced magnetization changes in long cobalt bars: Domain motion versus coherent <span class="hlt">rotation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Davis, S.; Adenwalla, S., E-mail: sadenwalla1@unl.edu; Borchers, J. A.</p> <p>2015-02-14</p> <p>A high frequency (88 MHz) traveling strain <span class="hlt">wave</span> on a piezoelectric substrate is shown to change the magnetization direction in 40 μm wide Co bars with an aspect ratio of 10{sup 3}. The rapidly alternating strain <span class="hlt">wave</span> <span class="hlt">rotates</span> the magnetization away from the long axis into the short axis direction, via magnetoelastic coupling. Strain-induced magnetization changes have previously been demonstrated in ferroelectric/ferromagnetic heterostructures, with excellent fidelity between the ferromagnet and the ferroelectric domains, but these experiments were limited to essentially dc frequencies. Both magneto-optical Kerr effect and polarized neutron reflectivity confirm that the traveling strain <span class="hlt">wave</span> does <span class="hlt">rotate</span> the magnetization awaymore » from the long axis direction and both yield quantitatively similar values for the <span class="hlt">rotated</span> magnetization. An investigation of the behavior of short axis magnetization with increasing strain <span class="hlt">wave</span> amplitude on a series of samples with variable edge roughness suggests that the magnetization reorientation that is seen proceeds solely via coherent <span class="hlt">rotation</span>. Polarized neutron reflectivity data provide direct experimental evidence for this model. This is consistent with expectations that domain wall motion cannot track the rapidly varying strain.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvF...2l2601Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvF...2l2601Y"><span>Experimental quantification of nonlinear time scales in inertial <span class="hlt">wave</span> <span class="hlt">rotating</span> turbulence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yarom, Ehud; Salhov, Alon; Sharon, Eran</p> <p>2017-12-01</p> <p>We study nonlinearities of inertial <span class="hlt">waves</span> in <span class="hlt">rotating</span> turbulence. At small Rossby numbers the kinetic energy in the system is contained in helical inertial <span class="hlt">waves</span> with time dependence amplitudes. In this regime the amplitude variations time scales are slow compared to <span class="hlt">wave</span> periods, and the spectrum is concentrated along the dispersion relation of the <span class="hlt">waves</span>. A nonlinear time scale was extracted from the width of the spectrum, which reflects the intensity of nonlinear <span class="hlt">wave</span> interactions. This nonlinear time scale is found to be proportional to (U.k ) -1, where k is the <span class="hlt">wave</span> vector and U is the root-mean-square horizontal velocity, which is dominated by large scales. This correlation, which indicates the existence of turbulence in which inertial <span class="hlt">waves</span> undergo weak nonlinear interactions, persists only for small Rossby numbers.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29225510','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29225510"><span><span class="hlt">Rotating</span> stars in relativity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Paschalidis, Vasileios; Stergioulas, Nikolaos</p> <p>2017-01-01</p> <p><span class="hlt">Rotating</span> relativistic stars have been studied extensively in recent years, both theoretically and observationally, because of the information they might yield about the equation of state of matter at extremely high densities and because they are considered to be promising sources of gravitational <span class="hlt">waves</span>. The latest theoretical understanding of <span class="hlt">rotating</span> stars in relativity is reviewed in this updated article. The sections on equilibrium properties and on nonaxisymmetric oscillations and instabilities in f -modes and r -modes have been updated. Several new sections have been added on equilibria in modified theories of gravity, <span class="hlt">approximate</span> universal relationships, the one-arm spiral instability, on analytic solutions for the exterior spacetime, <span class="hlt">rotating</span> stars in LMXBs, <span class="hlt">rotating</span> strange stars, and on <span class="hlt">rotating</span> stars in numerical relativity including both hydrodynamic and magnetohydrodynamic studies of these objects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JKPS...70.1049K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JKPS...70.1049K"><span>Dynamical cluster <span class="hlt">approximation</span> plus semiclassical <span class="hlt">approximation</span> study for a Mott insulator and d-<span class="hlt">wave</span> pairing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, SungKun; Lee, Hunpyo</p> <p>2017-06-01</p> <p>Via a dynamical cluster <span class="hlt">approximation</span> with N c = 4 in combination with a semiclassical <span class="hlt">approximation</span> (DCA+SCA), we study the doped two-dimensional Hubbard model. We obtain a plaquette antiferromagnetic (AF) Mott insulator, a plaquette AF ordered metal, a pseudogap (or d-<span class="hlt">wave</span> superconductor) and a paramagnetic metal by tuning the doping concentration. These features are similar to the behaviors observed in copper-oxide superconductors and are in qualitative agreement with the results calculated by the cluster dynamical mean field theory with the continuous-time quantum Monte Carlo (CDMFT+CTQMC) approach. The results of our DCA+SCA differ from those of the CDMFT+CTQMC approach in that the d-<span class="hlt">wave</span> superconducting order parameters are shown even in the high doped region, unlike the results of the CDMFT+CTQMC approach. We think that the strong plaquette AF orderings in the dynamical cluster <span class="hlt">approximation</span> (DCA) with N c = 4 suppress superconducting states with increasing doping up to strongly doped region, because frozen dynamical fluctuations in a semiclassical <span class="hlt">approximation</span> (SCA) approach are unable to destroy those orderings. Our calculation with short-range spatial fluctuations is initial research, because the SCA can manage long-range spatial fluctuations in feasible computational times beyond the CDMFT+CTQMC tool. We believe that our future DCA+SCA calculations should supply information on the fully momentum-resolved physical properties, which could be compared with the results measured by angle-resolved photoemission spectroscopy experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcMod.116...33B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcMod.116...33B"><span><span class="hlt">Approximation</span> of <span class="hlt">wave</span> action flux velocity in strongly sheared mean flows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Banihashemi, Saeideh; Kirby, James T.; Dong, Zhifei</p> <p>2017-08-01</p> <p>Spectral <span class="hlt">wave</span> models based on the <span class="hlt">wave</span> action equation typically use a theoretical framework based on depth uniform current to account for current effects on <span class="hlt">waves</span>. In the real world, however, currents often have variations over depth. Several recent studies have made use of a depth-weighted current U˜ due to [Skop, R. A., 1987. <span class="hlt">Approximate</span> dispersion relation for <span class="hlt">wave</span>-current interactions. J. Waterway, Port, Coastal, and Ocean Eng. 113, 187-195.] or [Kirby, J. T., Chen, T., 1989. Surface <span class="hlt">waves</span> on vertically sheared flows: <span class="hlt">approximate</span> dispersion relations. J. Geophys. Res. 94, 1013-1027.] in order to account for the effect of vertical current shear. Use of the depth-weighted velocity, which is a function of wavenumber (or frequency and direction) has been further simplified in recent applications by only utilizing a weighted current based on the spectral peak wavenumber. These applications do not typically take into account the dependence of U˜ on <span class="hlt">wave</span> number k, as well as erroneously identifying U˜ as the proper choice for current velocity in the <span class="hlt">wave</span> action equation. Here, we derive a corrected expression for the current component of the group velocity. We demonstrate its consistency using analytic results for a current with constant vorticity, and numerical results for a measured, strongly-sheared current profile obtained in the Columbia River. The effect of choosing a single value for current velocity based on the peak <span class="hlt">wave</span> frequency is examined, and we suggest an alternate strategy, involving a Taylor series expansion about the peak frequency, which should significantly extend the range of accuracy of current estimates available to the <span class="hlt">wave</span> model with minimal additional programming and data transfer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFDE30005C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFDE30005C"><span>Do inertial <span class="hlt">wave</span> interactions control the rate of energy dissipation of <span class="hlt">rotating</span> turbulence?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cortet, Pierre-Philippe; Campagne, Antoine; Machicoane, Nathanael; Gallet, Basile; Moisy, Frederic</p> <p>2015-11-01</p> <p>The scaling law of the energy dissipation rate, ɛ ~U3 / L (with U and L the characteristic velocity and lengthscale), is one of the most robust features of fully developed turbulence. How this scaling is affected by a background <span class="hlt">rotation</span> is still a controversial issue with importance for geo and astrophysical flows. At asymptotically small Rossby numbers Ro = U / ΩL , i.e. in the weakly nonlinear limit, <span class="hlt">wave</span>-turbulence arguments suggest that ɛ should be reduced by a factor Ro . Such scaling has however never been evidenced directly, neither experimentally nor numerically. We report here direct measurements of the injected power, and therefore of ɛ, in an experiment where a propeller is <span class="hlt">rotating</span> at a constant rate in a large volume of fluid <span class="hlt">rotating</span> at Ω. In co-<span class="hlt">rotation</span>, we find a transition between the <span class="hlt">wave</span>-turbulence scaling at small Ro and the classical Kolmogorov law at large Ro . The transition between these two regimes is characterized from experiments varying the propeller and tank dimensions. In counter-<span class="hlt">rotation</span>, the scenario is much richer with the observation of an additional peak of dissipation, similar to the one found in Taylor-Couette experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3115445','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3115445"><span>Fast <span class="hlt">Approximations</span> of the <span class="hlt">Rotational</span> Diffusion Tensor and their Application to Structural Assembly of Molecular Complexes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Berlin, Konstantin; O’Leary, Dianne P.; Fushman, David</p> <p>2011-01-01</p> <p>We present and evaluate a rigid-body, deterministic, molecular docking method, called ELMDOCK, that relies solely on the three-dimensional structure of the individual components and the overall <span class="hlt">rotational</span> diffusion tensor of the complex, obtained from nuclear spin-relaxation measurements. We also introduce a docking method, called ELMPATIDOCK, derived from ELMDOCK and based on the new concept of combining the shape-related restraints from <span class="hlt">rotational</span> diffusion with those from residual dipolar couplings, along with ambiguous contact/interface-related restraints obtained from chemical shift perturbations. ELMDOCK and ELMPATIDOCK use two novel <span class="hlt">approximations</span> of the molecular <span class="hlt">rotational</span> diffusion tensor that allow computationally efficient docking. We show that these <span class="hlt">approximations</span> are accurate enough to properly dock the two components of a complex without the need to recompute the diffusion tensor at each iteration step. We analyze the accuracy, robustness, and efficiency of these methods using synthetic relaxation data for a large variety of protein-protein complexes. We also test our method on three protein systems for which the structure of the complex and experimental relaxation data are available, and analyze the effect of flexible unstructured tails on the outcome of docking. Additionally, we describe a method for integrating the new <span class="hlt">approximation</span> methods into the existing docking approaches that use the <span class="hlt">rotational</span> diffusion tensor as a restraint. The results show that the proposed docking method is robust against experimental errors in the relaxation data or structural rearrangements upon complex formation and is computationally more efficient than current methods. The developed <span class="hlt">approximations</span> are accurate enough to be used in structure refinement protocols. PMID:21604302</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21604302','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21604302"><span>Fast <span class="hlt">approximations</span> of the <span class="hlt">rotational</span> diffusion tensor and their application to structural assembly of molecular complexes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Berlin, Konstantin; O'Leary, Dianne P; Fushman, David</p> <p>2011-07-01</p> <p>We present and evaluate a rigid-body, deterministic, molecular docking method, called ELMDOCK, that relies solely on the three-dimensional structure of the individual components and the overall <span class="hlt">rotational</span> diffusion tensor of the complex, obtained from nuclear spin-relaxation measurements. We also introduce a docking method, called ELMPATIDOCK, derived from ELMDOCK and based on the new concept of combining the shape-related restraints from <span class="hlt">rotational</span> diffusion with those from residual dipolar couplings, along with ambiguous contact/interface-related restraints obtained from chemical shift perturbations. ELMDOCK and ELMPATIDOCK use two novel <span class="hlt">approximations</span> of the molecular <span class="hlt">rotational</span> diffusion tensor that allow computationally efficient docking. We show that these <span class="hlt">approximations</span> are accurate enough to properly dock the two components of a complex without the need to recompute the diffusion tensor at each iteration step. We analyze the accuracy, robustness, and efficiency of these methods using synthetic relaxation data for a large variety of protein-protein complexes. We also test our method on three protein systems for which the structure of the complex and experimental relaxation data are available, and analyze the effect of flexible unstructured tails on the outcome of docking. Additionally, we describe a method for integrating the new <span class="hlt">approximation</span> methods into the existing docking approaches that use the <span class="hlt">rotational</span> diffusion tensor as a restraint. The results show that the proposed docking method is robust against experimental errors in the relaxation data or structural rearrangements upon complex formation and is computationally more efficient than current methods. The developed <span class="hlt">approximations</span> are accurate enough to be used in structure refinement protocols. Copyright © 2011 Wiley-Liss, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22667472-calculating-rotating-hydrodynamic-magnetohydrodynamic-waves-understand-magnetic-effects-dynamical-tides','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22667472-calculating-rotating-hydrodynamic-magnetohydrodynamic-waves-understand-magnetic-effects-dynamical-tides"><span>CALCULATING <span class="hlt">ROTATING</span> HYDRODYNAMIC AND MAGNETOHYDRODYNAMIC <span class="hlt">WAVES</span> TO UNDERSTAND MAGNETIC EFFECTS ON DYNAMICAL TIDES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Wei, Xing, E-mail: xing.wei@sjtu.edu.cn; Princeton University Observatory, Princeton, NJ 08544</p> <p>2016-09-01</p> <p>To understand magnetic effects on dynamical tides, we study the <span class="hlt">rotating</span> magnetohydrodynamic (MHD) flow driven by harmonic forcing. The linear responses are analytically derived in a periodic box under the local WKB <span class="hlt">approximation</span>. Both the kinetic and Ohmic dissipations at the resonant frequencies are calculated, and the various parameters are investigated. Although magnetic pressure may be negligible compared to thermal pressure, the magnetic field can be important for the first-order perturbation, e.g., dynamical tides. It is found that the magnetic field splits the resonant frequency, namely the <span class="hlt">rotating</span> hydrodynamic flow has only one resonant frequency, but the <span class="hlt">rotating</span> MHD flowmore » has two, one positive and the other negative. In the weak field regime the dissipations are asymmetric around the two resonant frequencies and this asymmetry is more striking with a weaker magnetic field. It is also found that both the kinetic and Ohmic dissipations at the resonant frequencies are inversely proportional to the Ekman number and the square of the wavenumber. The dissipation at the resonant frequency on small scales is almost equal to the dissipation at the non-resonant frequencies, namely the resonance takes its effect on the dissipation at intermediate length scales. Moreover, the <span class="hlt">waves</span> with phase propagation that is perpendicular to the magnetic field are much more damped. It is also interesting to find that the frequency-averaged dissipation is constant. This result suggests that in compact objects, magnetic effects on tidal dissipation should be considered.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22600175-modified-dust-ion-acoustic-surface-waves-semi-bounded-magnetized-plasma-containing-rotating-dust-grains','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22600175-modified-dust-ion-acoustic-surface-waves-semi-bounded-magnetized-plasma-containing-rotating-dust-grains"><span>Modified dust ion-acoustic surface <span class="hlt">waves</span> in a semi-bounded magnetized plasma containing the <span class="hlt">rotating</span> dust grains</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lee, Myoung-Jae; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 15588</p> <p>2016-05-15</p> <p>The dispersion relation for modified dust ion-acoustic surface <span class="hlt">waves</span> in the magnetized dusty plasma containing the <span class="hlt">rotating</span> dust grains is derived, and the effects of magnetic field configuration on the resonant growth rate are investigated. We present the results that the resonant growth rates of the <span class="hlt">wave</span> would increase with the ratio of ion plasma frequency to cyclotron frequency as well as with the increase of <span class="hlt">wave</span> number for the case of perpendicular magnetic field configuration when the ion plasma frequency is greater than the dust <span class="hlt">rotation</span> frequency. For the parallel magnetic field configuration, we find that the instability occursmore » only for some limited ranges of the <span class="hlt">wave</span> number and the ratio of ion plasma frequency to cyclotron frequency. The resonant growth rate is found to decrease with the increase of the <span class="hlt">wave</span> number. The influence of dust <span class="hlt">rotational</span> frequency on the instability is also discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950054920&hterms=How+dwarf+stars+formed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHow%2Bdwarf%2Bstars%2Bformed','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950054920&hterms=How+dwarf+stars+formed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHow%2Bdwarf%2Bstars%2Bformed"><span>Gravitational radiation from rapidly <span class="hlt">rotating</span> nascent neutron stars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lai, Dong; Shapiro, Stuart L.</p> <p>1995-01-01</p> <p>We study the secular evolution and gravitational <span class="hlt">wave</span> signature of a newly formed, rapidly <span class="hlt">rotating</span> neutron star. The neutron star may arise from core collapse in a massive star or from the accretion-induced collapse of a white dwarf. After a brief dynamical phase, the nascent neutron star settles into an axisymmetric, secularly unstable state. Gravitational radiation drives the star to a nonaxisymmetric, stationary equilibrium configuration via the bar-mode instability. The emitted quasi-periodic gravitational <span class="hlt">waves</span> have a unique signature: the <span class="hlt">wave</span> frequency sweeps downward from a few hundred Hertz to zero, while the <span class="hlt">wave</span> amplitude increase from zero to a maximum and then decays back to zero. Such a <span class="hlt">wave</span> signal could detected by broadband gravitational <span class="hlt">wave</span> interferometers currently being constructed. We also characterize two other types of gravitational <span class="hlt">wave</span> signals that could arise in principle from a rapidly <span class="hlt">rotating</span>, secularly unstable neutron star: a high-frequency (f greater than or <span class="hlt">approximately</span> = 1000 Hz) <span class="hlt">wave</span> which increases the pattern-speed of the star, and a <span class="hlt">wave</span> that actually increases the angular momentum of the star.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840059708&hterms=Tidal+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DTidal%2Bwaves','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840059708&hterms=Tidal+waves&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DTidal%2Bwaves"><span>The generation and propagation of internal gravity <span class="hlt">waves</span> in a <span class="hlt">rotating</span> fluid</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Maxworthy, T.; Chabert Dhieres, G.; Didelle, H.</p> <p>1984-01-01</p> <p>The present investigation is concerned with an extension of a study conducted bu Maxworthy (1979) on internal <span class="hlt">wave</span> generation by barotropic tidal flow over bottom topography. A short series of experiments was carried out during a limited time period on a large (14-m diameter) <span class="hlt">rotating</span> table. It was attempted to obtain, in particular, information regarding the plan form of the <span class="hlt">waves</span>, the exact character of the flow over the obstacle, and the evolution of the <span class="hlt">waves</span>. The main basin was a dammed section of a long free surface water tunnel. The obstacle was towed back and forth by a wire harness connected to an electronically controlled hydraulic piston, the stroke and period of which could be independently varied. Attention is given to the evolution of the <span class="hlt">wave</span> crests, the formation of solitary <span class="hlt">wave</span> groups the evolution of the three-dimensional <span class="hlt">wave</span> field <span class="hlt">wave</span> shapes, the <span class="hlt">wave</span> amplitudes, and particle motion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhRvA..88e3821Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhRvA..88e3821Y"><span>Effects of counter-<span class="hlt">rotating-wave</span> terms of the driving field on the spectrum of resonance fluorescence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yan, Yiying; Lü, Zhiguo; Zheng, Hang</p> <p>2013-11-01</p> <p>We investigate the fluorescence spectrum of a two-level system driven by a monochromatic classical field by the Born-Markovian master equation based on a unitary transformation. The main purpose is to understand the effects of counter-<span class="hlt">rotating-wave</span> terms of the driving on spectral features of the fluorescence. We have derived an analytical expression for the fluorescence spectrum, which is different from Mollow's theory, while Mollow's result on resonance is the limiting case of ours in moderately weak driving regimes. Our results demonstrate precisely that the counter-<span class="hlt">rotating-wave</span> terms of the driving play an important role in the fluorescence spectrum for intense driving: (i) the counter-<span class="hlt">rotating</span> coupling suppresses the red sideband in the Mollow triplet and it enhances the blue one in explicitly contrast to the well-known equal intensity of the sideband in Mollow's theory, (ii) the higher-order Mollow triplets appear as a characteristic spectral feature arising from counter-<span class="hlt">rotating-wave</span> terms of the driving, and (iii) a significant frequency shift of the sidebands is observed, which depends on both the detuning and driving strength.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27127951','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27127951"><span>Circular Polarizations of Gravitational <span class="hlt">Waves</span> from Core-Collapse Supernovae: A Clear Indication of Rapid <span class="hlt">Rotation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hayama, Kazuhiro; Kuroda, Takami; Nakamura, Ko; Yamada, Shoichi</p> <p>2016-04-15</p> <p>We propose to employ the circular polarization of gravitational <span class="hlt">waves</span> emitted by core-collapse supernovae as an unequivocal indication of rapid <span class="hlt">rotation</span> deep in their cores just prior to collapse. It has been demonstrated by three dimensional simulations that nonaxisymmetric accretion flows may develop spontaneously via hydrodynamical instabilities in the postbounce cores. It is not surprising, then, that the gravitational <span class="hlt">waves</span> emitted by such fluid motions are circularly polarized. We show, in this Letter, that a network of the second generation detectors of gravitational <span class="hlt">waves</span> worldwide may be able to detect such polarizations up to the opposite side of the Galaxy as long as the <span class="hlt">rotation</span> period of the core is shorter than a few seconds prior to collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JOUC...15..789Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JOUC...15..789Y"><span><span class="hlt">Approximate</span> optimal tracking control for near-surface AUVs with <span class="hlt">wave</span> disturbances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Qing; Su, Hao; Tang, Gongyou</p> <p>2016-10-01</p> <p>This paper considers the optimal trajectory tracking control problem for near-surface autonomous underwater vehicles (AUVs) in the presence of <span class="hlt">wave</span> disturbances. An <span class="hlt">approximate</span> optimal tracking control (AOTC) approach is proposed. Firstly, a six-degrees-of-freedom (six-DOF) AUV model with its body-fixed coordinate system is decoupled and simplified and then a nonlinear control model of AUVs in the vertical plane is given. Also, an exosystem model of <span class="hlt">wave</span> disturbances is constructed based on Hirom <span class="hlt">approximation</span> formula. Secondly, the time-parameterized desired trajectory which is tracked by the AUV's system is represented by the exosystem. Then, the coupled two-point boundary value (TPBV) problem of optimal tracking control for AUVs is derived from the theory of quadratic optimal control. By using a recently developed successive <span class="hlt">approximation</span> approach to construct sequences, the coupled TPBV problem is transformed into a problem of solving two decoupled linear differential sequences of state vectors and adjoint vectors. By iteratively solving the two equation sequences, the AOTC law is obtained, which consists of a nonlinear optimal feedback item, an expected output tracking item, a feedforward disturbances rejection item, and a nonlinear compensatory term. Furthermore, a <span class="hlt">wave</span> disturbances observer model is designed in order to solve the physically realizable problem. Simulation is carried out by using the Remote Environmental Unit (REMUS) AUV model to demonstrate the effectiveness of the proposed algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvB..97l5428P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvB..97l5428P"><span>Surface <span class="hlt">waves</span> on multilayer hyperbolic metamaterials: Operator approach to effective medium <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Popov, Vladislav; Lavrinenko, Andrei V.; Novitsky, Andrey</p> <p>2018-03-01</p> <p>In this paper, we elaborate on the operator effective medium <span class="hlt">approximation</span> developed recently in Popov et al. [Phys. Rev. B 94, 085428 (2016), 10.1103/PhysRevB.94.085428] to get insight into the surface polariton excitation at the interface of a multilayer hyperbolic metamaterial (HMM). In particular, we find that HMMs with bilayer unit cells support the TE- and TM-polarized surface <span class="hlt">waves</span> beyond the Maxwell Garnett <span class="hlt">approximation</span> due to the spatial dispersion interpreted as effective magnetoelectric coupling. The latter is also responsible for the dependence of surface <span class="hlt">wave</span> propagation on the order of layers in the unit cell. Elimination of the magnetoelectric coupling in three-layer unit cells complying with inversion symmetry restores the qualitative regularity of the Maxwell Garnett <span class="hlt">approximation</span>, as well as strongly suppresses the influence of the order of layers in the unit cell.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22403270-explicit-approximations-estimate-perturbative-diffusivity-presence-convectivity-damping-iii-cylindrical-approximations-heat-waves-traveling-inwards','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22403270-explicit-approximations-estimate-perturbative-diffusivity-presence-convectivity-damping-iii-cylindrical-approximations-heat-waves-traveling-inwards"><span>Explicit <span class="hlt">approximations</span> to estimate the perturbative diffusivity in the presence of convectivity and damping. III. Cylindrical <span class="hlt">approximations</span> for heat <span class="hlt">waves</span> traveling inwards</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Berkel, M. van; Fellow of the Japan Society for the Promotion of Science; FOM Institute DIFFER-Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein</p> <p></p> <p>In this paper, a number of new explicit <span class="hlt">approximations</span> are introduced to estimate the perturbative diffusivity (χ), convectivity (V), and damping (τ) in cylindrical geometry. For this purpose, the harmonic components of heat <span class="hlt">waves</span> induced by localized deposition of modulated power are used. The <span class="hlt">approximations</span> are based on the heat equation in cylindrical geometry using the symmetry (Neumann) boundary condition at the plasma center. This means that the <span class="hlt">approximations</span> derived here should be used only to estimate transport coefficients between the plasma center and the off-axis perturbative source. If the effect of cylindrical geometry is small, it is also possiblemore » to use semi-infinite domain <span class="hlt">approximations</span> presented in Part I and Part II of this series. A number of new <span class="hlt">approximations</span> are derived in this part, Part III, based upon continued fractions of the modified Bessel function of the first kind and the confluent hypergeometric function of the first kind. These <span class="hlt">approximations</span> together with the <span class="hlt">approximations</span> based on semi-infinite domains are compared for heat <span class="hlt">waves</span> traveling towards the center. The relative error for the different derived <span class="hlt">approximations</span> is presented for different values of the frequency, transport coefficients, and dimensionless radius. Moreover, it is shown how combinations of different explicit formulas can be used to estimate the transport coefficients over a large parameter range for cases without convection and damping, cases with damping only, and cases with convection and damping. The relative error between the <span class="hlt">approximation</span> and its underlying model is below 2% for the case, where only diffusivity and damping are considered. If also convectivity is considered, the diffusivity can be estimated well in a large region, but there is also a large region in which no suitable <span class="hlt">approximation</span> is found. This paper is the third part (Part III) of a series of three papers. In Part I, the semi-infinite slab <span class="hlt">approximations</span> have been treated. In</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982PhRvC..26.2152G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982PhRvC..26.2152G"><span>Photopions from nuclei in the distorted-<span class="hlt">wave</span> impulse <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Girija, V.; Devanathan, V.</p> <p>1982-11-01</p> <p>The formalism for photoproduction of pions from nuclei has been developed in the distorted-<span class="hlt">wave</span> impulse <span class="hlt">approximation</span>, taking into account the effect of the change in pion momentum in nuclear medium. Detailed calculations have been done for the reaction 16O(γ, π+)16N for photon energies from 170 to 380 MeV, with a view to investigate the effect due to the gradient operator ∇-->π for momentum of the pion and test the sensitivity of the photopion cross sections to the details of the pion-nucleus optical potential. The results clearly establish that the gradient operator increases the cross sections throughout the energy region considered, the increase being small at lower energies. Also with ∇-->π, the cross sections are rendered less sensitive to the optical potential. The calculated differential cross sections agree very well with the recent experimental data of Shoda et al. for γ-ray energy of 200 MeV. However, the cross sections obtained at medium energies are higher when compared to the available experimental data. NUCLEAR REACTIONS π+ photoproduction from 16O; distorted <span class="hlt">wave</span> impulse <span class="hlt">approximation</span>; pion-nucleus optical potentials; gradient operator for the pion momentum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814850E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814850E"><span><span class="hlt">Wave</span> generation by fracture initiation and propagation in geomaterials with internal <span class="hlt">rotations</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Esin, Maxim; Pasternak, Elena; Dyskin, Arcady; Xu, Yuan</p> <p>2016-04-01</p> <p>Crack or fracture initiation and propagation in geomaterials are sources of <span class="hlt">waves</span> and is important in both stability and fracture (e.g. hydraulic fracture) monitoring. Many geomaterials consist of particles or other constituents capable of <span class="hlt">rotating</span> with respect to each other, either due to the absence of the binder phase (fragmented materials) or due to extensive damage of the cement between the constituents inflicted by previous loading. In investigating the <span class="hlt">wave</span> generated in fracturing it is important to distinguish between the cases when the fracture is instantaneously initiated to its full length or propagates from a smaller initial crack. We show by direct physical experiments and discrete element modelling of 2D arrangements of unbonded disks that under compressive load fractures are initiated instantaneously as a result of the material instability and localisation. Such fractures generate <span class="hlt">waves</span> as a single impulse impact. When the fractures propagate, they produce a sequence of impulses associated with the propagation steps. This manifests itself as acoustic (microseismic) emission whose temporal pattern contains the information of the fracture geometry, such as fractal dimension of the fracture. The description of this process requires formulating criteria of crack growth capable of taking into account the internal <span class="hlt">rotations</span>. We developed an analytical solution based on the Cosserat continuum where each point of body has three translational and three <span class="hlt">rotational</span> degrees of freedom. When the Cosserat characteristic lengths are comparable with the grain sizes, the simplified equations of small-scale Cosserat continuum can be used. We established that the order of singularity of the main asymptotic term for moment stress is higher than the order of singularity for conventional stress. Therefore, the mutual <span class="hlt">rotation</span> of particles and related bending and/or twisting of the bonds between the particles represent an unconventional mechanism of crack propagation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...512700F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...512700F"><span>Anomalous incident-angle and elliptical-polarization <span class="hlt">rotation</span> of an elastically refracted P-<span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fa, Lin; Fa, Yuxiao; Zhang, Yandong; Ding, Pengfei; Gong, Jiamin; Li, Guohui; Li, Lijun; Tang, Shaojie; Zhao, Meishan</p> <p>2015-08-01</p> <p>We report a newly discovered anomalous incident-angle of an elastically refracted P-<span class="hlt">wave</span>, arising from a P-<span class="hlt">wave</span> impinging on an interface between two VTI media with strong anisotropy. This anomalous incident-angle is found to be located in the post-critical incident-angle region corresponding to a refracted P-<span class="hlt">wave</span>. Invoking Snell’s law for a refracted P-<span class="hlt">wave</span> provides two distinctive solutions before and after the anomalous incident-angle. For an inhomogeneously refracted and elliptically polarized P-<span class="hlt">wave</span> at the anomalous incident-angle, its <span class="hlt">rotational</span> direction experiences an acute variation, from left-hand elliptical to right-hand elliptical polarization. The new findings provide us an enhanced understanding of acoustical-<span class="hlt">wave</span> scattering and lead potentially to widespread and novel applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AIPC.1959e0025P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AIPC.1959e0025P"><span>Stability of <span class="hlt">wave</span> processes in a <span class="hlt">rotating</span> electrically conducting fluid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Peregudin, S. I.; Peregudina, E. S.; Kholodova, S. E.</p> <p>2018-05-01</p> <p>The paper puts forward a mathematical model of dynamics of spatial large-scale motions in a <span class="hlt">rotating</span> layer of electrically conducting incompressible perfect fluid of variable depth with due account of dissipative effects. The resulting boundary-value problem is reduced to a vector system of partial differential equations for any values of the Reynolds number. Theoretical analysis of the so-obtained analytical solution reveals the effect of the magnetic field diffusion on the stability of the <span class="hlt">wave</span> mode — namely, with the removed external magnetic field, the diffusion of the magnetic field promotes its damping. Besides, a criterion of stability of a <span class="hlt">wave</span> mode is obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JMFM..tmp....8M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JMFM..tmp....8M"><span>The KP <span class="hlt">Approximation</span> Under a Weak Coriolis Forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melinand, Benjamin</p> <p>2018-02-01</p> <p>In this paper, we study the asymptotic behavior of weakly transverse water-<span class="hlt">waves</span> under a weak Coriolis forcing in the long <span class="hlt">wave</span> regime. We derive the Boussinesq-Coriolis equations in this setting and we provide a rigorous justification of this model. Then, from these equations, we derive two other asymptotic models. When the Coriolis forcing is weak, we fully justify the <span class="hlt">rotation</span>-modified Kadomtsev-Petviashvili equation (also called Grimshaw-Melville equation). When the Coriolis forcing is very weak, we rigorously justify the Kadomtsev-Petviashvili equation. This work provides the first mathematical justification of the KP <span class="hlt">approximation</span> under a Coriolis forcing.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..MARF52013Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..MARF52013Y"><span>Charge noise in quantum dot qubits: beyond the Markovian <span class="hlt">approximation</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Yuan-Chi; Friesen, Mark; Coppersmith, S. N.</p> <p></p> <p>Charge noise is a limiting factor in the performance of semiconductor quantum dot qubits, including both spin and charge qubits. In this work, we develop an analytical formalism for treating semiclassical noise beyond the Markovian <span class="hlt">approximation</span>, which allows us to investigate noise models relevant for quantum dots, such as 1 / f noise. We apply our methods to both charge qubits and quantum dot hybrid qubits, and study the effects of charge noise on single-qubit <span class="hlt">rotations</span> in these systems. The formalism is also directly applicable to the case of strong microwave driving, for which the <span class="hlt">rotating</span> <span class="hlt">wave</span> <span class="hlt">approximation</span> breaks down. This work was supported in part by ARO (W911NF-12-0607) and ONR (N00014-15-1-0029), and the University of Wisconsin-Madison.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018A%26A...609A.118A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018A%26A...609A.118A"><span>Atmospheric thermal tides and planetary spin. I. The complex interplay between stratification and <span class="hlt">rotation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Auclair-Desrotour, P.; Mathis, S.; Laskar, J.</p> <p>2018-02-01</p> <p>Context. Thermal atmospheric tides can torque telluric planets away from spin-orbit synchronous <span class="hlt">rotation</span>, as observed in the case of Venus. They thus participate in determining the possible climates and general circulations of the atmospheres of these planets. Aims: The thermal tidal torque exerted on an atmosphere depends on its internal structure and <span class="hlt">rotation</span> and on the tidal frequency. Particularly, it strongly varies with the convective stability of the entropy stratification. This dependence has to be characterized to constrain and predict the <span class="hlt">rotational</span> properties of observed telluric exoplanets. Moreover, it is necessary to validate the <span class="hlt">approximations</span> used in global modelings such as the traditional <span class="hlt">approximation</span>, which is used to obtain separable solutions for tidal <span class="hlt">waves</span>. Methods: We wrote the equations governing the dynamics of thermal tides in a local vertically stratified section of a <span class="hlt">rotating</span> planetary atmosphere by taking into account the effects of the complete Coriolis acceleration on tidal <span class="hlt">waves</span>. This allowed us to analytically derive the tidal torque and the tidally dissipated energy, which we used to discuss the possible regimes of tidal dissipation and to examine the key role played by stratification. Results: In agreement with early studies, we find that the frequency dependence of the thermal atmospheric tidal torque in the vicinity of synchronization can be <span class="hlt">approximated</span> by a Maxwell model. This behavior corresponds to weakly stably stratified or convective fluid layers, as observed previously. A strong stable stratification allows gravity <span class="hlt">waves</span> to propagate, and makes the tidal torque negligible. The transition is continuous between these two regimes. The traditional <span class="hlt">approximation</span> appears to be valid in thin atmospheres and in regimes where the <span class="hlt">rotation</span> frequency is dominated by the forcing or the buoyancy frequencies. Conclusions: Depending on the stability of their atmospheres with respect to convection, observed exoplanets can be tidally</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1304700','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1304700"><span>A high-order time-parallel scheme for solving <span class="hlt">wave</span> propagation problems via the direct construction of an <span class="hlt">approximate</span> time-evolution operator</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Haut, T. S.; Babb, T.; Martinsson, P. G.</p> <p>2015-06-16</p> <p>Our manuscript demonstrates a technique for efficiently solving the classical <span class="hlt">wave</span> equation, the shallow water equations, and, more generally, equations of the form ∂u/∂t=Lu∂u/∂t=Lu, where LL is a skew-Hermitian differential operator. The idea is to explicitly construct an <span class="hlt">approximation</span> to the time-evolution operator exp(τL)exp(τL) for a relatively large time-step ττ. Recently developed techniques for <span class="hlt">approximating</span> oscillatory scalar functions by rational functions, and accelerated algorithms for computing functions of discretized differential operators are exploited. Principal advantages of the proposed method include: stability even for large time-steps, the possibility to parallelize in time over many characteristic wavelengths and large speed-ups over existingmore » methods in situations where simulation over long times are required. Numerical examples involving the 2D <span class="hlt">rotating</span> shallow water equations and the 2D <span class="hlt">wave</span> equation in an inhomogenous medium are presented, and the method is compared to the 4th order Runge–Kutta (RK4) method and to the use of Chebyshev polynomials. The new method achieved high accuracy over long-time intervals, and with speeds that are orders of magnitude faster than both RK4 and the use of Chebyshev polynomials.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28618504','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28618504"><span><span class="hlt">Wave</span> propagation reversal for wavy vortices in wide-gap counter-<span class="hlt">rotating</span> cylindrical Couette flow.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Altmeyer, S; Lueptow, Richard M</p> <p>2017-05-01</p> <p>We present a numerical study of wavy supercritical cylindrical Couette flow between counter-<span class="hlt">rotating</span> cylinders in which the wavy pattern propagates either prograde with the inner cylinder or retrograde opposite the <span class="hlt">rotation</span> of the inner cylinder. The <span class="hlt">wave</span> propagation reversals from prograde to retrograde and vice versa occur at distinct values of the inner cylinder Reynolds number when the associated frequency of the wavy instability vanishes. The reversal occurs for both twofold and threefold symmetric wavy vortices. Moreover, the <span class="hlt">wave</span> propagation reversal only occurs for sufficiently strong counter-<span class="hlt">rotation</span>. The flow pattern reversal appears to be intrinsic in the system as either periodic boundary conditions or fixed end wall boundary conditions for different system sizes always result in the <span class="hlt">wave</span> propagation reversal. We present a detailed bifurcation sequence and parameter space diagram with respect to retrograde behavior of wavy flows. The retrograde propagation of the instability occurs when the inner Reynolds number is about two times the outer Reynolds number. The mechanism for the retrograde propagation is associated with the inviscidly unstable region near the inner cylinder and the direction of the global average azimuthal velocity. Flow dynamics, spatio-temporal behavior, global mean angular velocity, and torque of the flow with the wavy pattern are explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MSSP...98.1077B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MSSP...98.1077B"><span>Mechanical circulator for elastic <span class="hlt">waves</span> by using the nonreciprocity of flexible <span class="hlt">rotating</span> rings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beli, Danilo; Silva, Priscilla Brandão; Arruda, José Roberto de França</p> <p>2018-01-01</p> <p>Circulators have a wide range of applications in <span class="hlt">wave</span> manipulation. They provide a nonreciprocal response by breaking the time-reversal symmetry. In the mechanical field, nonlinear isolators and ferromagnetic circulators can be used for this objective. However, they require high power and high volumes. Herein, a flexible <span class="hlt">rotating</span> ring is used to break the time-reversal symmetry as a result of the combined effect of Coriolis acceleration and material damping. Complete asymmetry of oscillating and evanescent components of wavenumbers is achieved. The elastic ring produces a nonreciprocal response that is used to design a three port mechanical circulator. The <span class="hlt">rotational</span> speed for maximum transmission in one port and isolation in the other one is determined using analytical equations. A spectral element formulation is used to compute the complex dispersion diagrams and the forced response. Waveguides that support longitudinal and flexural <span class="hlt">waves</span> are investigated. In this case, the ring nonreciprocity is modulated by the waveguide reciprocal response and the transmission coefficients can be affected. The proposed device is compact, nonferromagnetic, and may open new directions for elastic <span class="hlt">wave</span> manipulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004ASAJ..115.2473M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004ASAJ..115.2473M"><span>Born <span class="hlt">approximation</span> for scattering by evanescent <span class="hlt">waves</span>: Comparison with exact scattering by an infinite fluid cylinder</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marston, Philip L.</p> <p>2004-05-01</p> <p>In some situations, evanescent <span class="hlt">waves</span> can be an important component of the acoustic field within the sea bottom. For this reason (as well as to advance the understanding of scattering processes) it can be helpful to examine the modifications to scattering theory resulting from evanescence. Modifications to ray theory were examined in a prior <span class="hlt">approximation</span> [P. L. Marston, J. Acoust. Soc. Am. 113, 2320 (2003)]. The new research concerns the modifications to the low-frequency Born <span class="hlt">approximation</span> and confirmation by comparison with the exact two-dimensional scattering by a fluid cylinder. In the case of a circular cylinder having the same density as the surroundings but having a compressibility contrast with the surroundings, the Born <span class="hlt">approximation</span> with a nonevanescent incident <span class="hlt">wave</span> gives only monopole scattering. When the cylinder has a density contrast and the same compressibility as the surroundings the regular Born <span class="hlt">approximation</span> gives only dipole scattering (with the dipole oriented along to the incident wavevector). In both cases when the Born <span class="hlt">approximation</span> is modified to include the evanescence of the incident <span class="hlt">wave</span>, an additional dipole scattering term is evident. In each case the new dipole is oriented along to the decay axis of the evanescent <span class="hlt">wave</span>. [Research supported by ONR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950015987','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950015987"><span><span class="hlt">Wave</span> Journal Bearing. Part 1: Analysis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dimofte, Florin</p> <p>1995-01-01</p> <p>A <span class="hlt">wave</span> journal bearing concept features a <span class="hlt">waved</span> inner bearing diameter of the non-<span class="hlt">rotating</span> bearing side and it is an alternative to the plain journal bearing. The <span class="hlt">wave</span> journal bearing has a significantly increased load capacity in comparison to the plain journal bearing operating at the same eccentricity. It also offers greater stability than the plain circular bearing under all operating conditions. The <span class="hlt">wave</span> bearing's design is relatively simple and allows the shaft to <span class="hlt">rotate</span> in either direction. Three <span class="hlt">wave</span> bearings are sensitive to the direction of an applied stationary side load. Increasing the number of <span class="hlt">waves</span> reduces the <span class="hlt">wave</span> bearing's sensitivity to the direction of the applied load relative to the <span class="hlt">wave</span>. However, the range in which the bearing performance can be varied decreases as the number of <span class="hlt">waves</span> increases. Therefore, both the number and the amplitude of the <span class="hlt">waves</span> must be properly selected to optimize the <span class="hlt">wave</span> bearing design for a specific application. It is concluded that the stiffness of an air journal bearing, due to hydrodynamic effect, could be doubled and made to run stably by using a six or eight <span class="hlt">wave</span> geometry with a <span class="hlt">wave</span> amplitude <span class="hlt">approximately</span> half of the bearing radial clearance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22401222','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22401222"><span>Condensates of p-<span class="hlt">wave</span> pairs are exact solutions for <span class="hlt">rotating</span> two-component Bose gases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Papenbrock, T; Reimann, S M; Kavoulakis, G M</p> <p>2012-02-17</p> <p>We derive exact analytical results for the <span class="hlt">wave</span> functions and energies of harmonically trapped two-component Bose-Einstein condensates with weakly repulsive interactions under <span class="hlt">rotation</span>. The isospin symmetric <span class="hlt">wave</span> functions are universal and do not depend on the matrix elements of the two-body interaction. The comparison with the results from numerical diagonalization shows that the ground state and low-lying excitations consist of condensates of p-<span class="hlt">wave</span> pairs for repulsive contact interactions, Coulomb interactions, and the repulsive interactions between aligned dipoles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036006','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036006"><span><span class="hlt">Approximation</span> to cutoffs of higher modes of Rayleigh <span class="hlt">waves</span> for a layered earth model</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Xu, Y.; Xia, J.; Miller, R.D.</p> <p>2009-01-01</p> <p>A cutoff defines the long-period termination of a Rayleigh-<span class="hlt">wave</span> higher mode and, therefore is a key characteristic of higher mode energy relationship to several material properties of the subsurface. Cutoffs have been used to estimate the shear-<span class="hlt">wave</span> velocity of an underlying half space of a layered earth model. In this study, we describe a method that replaces the multilayer earth model with a single surface layer overlying the half-space model, accomplished by harmonic averaging of velocities and arithmetic averaging of densities. Using numerical comparisons with theoretical models validates the single-layer <span class="hlt">approximation</span>. Accuracy of this single-layer <span class="hlt">approximation</span> is best defined by values of the calculated error in the frequency and phase velocity estimate at a cutoff. Our proposed method is intuitively explained using ray theory. Numerical results indicate that a cutoffs frequency is controlled by the averaged elastic properties within the passing depth of Rayleigh <span class="hlt">waves</span> and the shear-<span class="hlt">wave</span> velocity of the underlying half space. ?? Birkh??user Verlag, Basel 2009.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28657192','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28657192"><span>Effects of age and pathology on shear <span class="hlt">wave</span> speed of the human <span class="hlt">rotator</span> cuff.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baumer, Timothy G; Dischler, Jack; Davis, Leah; Labyed, Yassin; Siegal, Daniel S; van Holsbeeck, Marnix; Moutzouros, Vasilios; Bey, Michael J</p> <p>2018-01-01</p> <p><span class="hlt">Rotator</span> cuff tears are common and often repaired surgically, but post-operative repair tissue healing, and shoulder function can be unpredictable. Tear chronicity is believed to influence clinical outcomes, but conventional clinical approaches for assessing tear chronicity are subjective. Shear <span class="hlt">wave</span> elastography (SWE) is a promising technique for assessing soft tissue via estimates of shear <span class="hlt">wave</span> speed (SWS), but this technique has not been used extensively on the <span class="hlt">rotator</span> cuff. Specifically, the effects of age and pathology on <span class="hlt">rotator</span> cuff SWS are not well known. The objectives of this study were to assess the association between SWS and age in healthy, asymptomatic subjects, and to compare measures of SWS between patients with a <span class="hlt">rotator</span> cuff tear and healthy, asymptomatic subjects. SWE images of the supraspinatus muscle and intramuscular tendon were acquired from 19 asymptomatic subjects and 11 patients with a <span class="hlt">rotator</span> cuff tear. Images were acquired with the supraspinatus under passive and active (i.e., minimal activation) conditions. Mean SWS was positively associated with age in the supraspinatus muscle and tendon under passive and active conditions (p ≤ 0.049). Compared to asymptomatic subjects, patients had a lower mean SWS in their muscle and tendon under active conditions (p ≤ 0.024), but no differences were detected under passive conditions (p ≥ 0.783). These findings identify the influences of age and pathology on SWS in the <span class="hlt">rotator</span> cuff. These preliminary findings are an important step toward evaluating the clinical utility of SWE for assessing <span class="hlt">rotator</span> cuff pathology. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:282-288, 2018. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...5E8756Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...5E8756Z"><span>Analytical Solution for the Anisotropic Rabi Model: Effects of Counter-<span class="hlt">Rotating</span> Terms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Guofeng; Zhu, Hanjie</p> <p>2015-03-01</p> <p>The anisotropic Rabi model, which was proposed recently, differs from the original Rabi model: the <span class="hlt">rotating</span> and counter-<span class="hlt">rotating</span> terms are governed by two different coupling constants. This feature allows us to vary the counter-<span class="hlt">rotating</span> interaction independently and explore the effects of it on some quantum properties. In this paper, we eliminate the counter-<span class="hlt">rotating</span> terms <span class="hlt">approximately</span> and obtain the analytical energy spectrums and wavefunctions. These analytical results agree well with the numerical calculations in a wide range of the parameters including the ultrastrong coupling regime. In the weak counter-<span class="hlt">rotating</span> coupling limit we find out that the counter-<span class="hlt">rotating</span> terms can be considered as the shifts to the parameters of the Jaynes-Cummings model. This modification shows the validness of the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span> on the assumption of near-resonance and relatively weak coupling. Moreover, the analytical expressions of several physics quantities are also derived, and the results show the break-down of the U(1)-symmetry and the deviation from the Jaynes-Cummings model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25736827','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25736827"><span>Analytical solution for the anisotropic Rabi model: effects of counter-<span class="hlt">rotating</span> terms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Guofeng; Zhu, Hanjie</p> <p>2015-03-04</p> <p>The anisotropic Rabi model, which was proposed recently, differs from the original Rabi model: the <span class="hlt">rotating</span> and counter-<span class="hlt">rotating</span> terms are governed by two different coupling constants. This feature allows us to vary the counter-<span class="hlt">rotating</span> interaction independently and explore the effects of it on some quantum properties. In this paper, we eliminate the counter-<span class="hlt">rotating</span> terms <span class="hlt">approximately</span> and obtain the analytical energy spectrums and wavefunctions. These analytical results agree well with the numerical calculations in a wide range of the parameters including the ultrastrong coupling regime. In the weak counter-<span class="hlt">rotating</span> coupling limit we find out that the counter-<span class="hlt">rotating</span> terms can be considered as the shifts to the parameters of the Jaynes-Cummings model. This modification shows the validness of the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span> on the assumption of near-resonance and relatively weak coupling. Moreover, the analytical expressions of several physics quantities are also derived, and the results show the break-down of the U(1)-symmetry and the deviation from the Jaynes-Cummings model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11863657','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11863657"><span>Quasiperiodic <span class="hlt">waves</span> at the onset of zero-Prandtl-number convection with <span class="hlt">rotation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kumar, Krishna; Chaudhuri, Sanjay; Das, Alaka</p> <p>2002-02-01</p> <p>We show the possibility of temporally quasiperiodic <span class="hlt">waves</span> at the onset of thermal convection in a thin horizontal layer of slowly <span class="hlt">rotating</span> zero-Prandtl-number Boussinesq fluid confined between stress-free conducting boundaries. Two independent frequencies emerge due to an interaction between straight rolls and <span class="hlt">waves</span> along these rolls in the presence of Coriolis force, if the Taylor number is raised above a critical value. Constructing a dynamical system for the hydrodynamical problem, the competition between the interacting instabilities is analyzed. The forward bifurcation from the conductive state is self-tuned.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.214...14O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.214...14O"><span><span class="hlt">Approximate</span> nonlinear multiparameter inversion for multicomponent single and double P-<span class="hlt">wave</span> scattering in isotropic elastic media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ouyang, Wei; Mao, Weijian</p> <p>2018-07-01</p> <p>An asymptotic quadratic true-amplitude inversion method for isotropic elastic P <span class="hlt">waves</span> is proposed to invert medium parameters. The multicomponent P-<span class="hlt">wave</span> scattered wavefield is computed based on a forward relationship using second-order Born <span class="hlt">approximation</span> and corresponding high-frequency ray theoretical methods. Within the local double scattering mechanism, the P-<span class="hlt">wave</span> transmission factors are elaborately calculated, which results in the radiation pattern for P-<span class="hlt">wave</span> scattering being a quadratic combination of the density and Lamé's moduli perturbation parameters. We further express the elastic P-<span class="hlt">wave</span> scattered wavefield in a form of generalized Radon transform. After introducing classical backprojection operators, we obtain an <span class="hlt">approximate</span> solution of the inverse problem by solving a quadratic nonlinear system. Numerical tests with synthetic data computed by finite-differences scheme demonstrate that our quadratic inversion can accurately invert perturbation parameters for strong perturbations, compared with the P-<span class="hlt">wave</span> single-scattering linear inversion method. Although our inversion strategy here is only syncretized with P-<span class="hlt">wave</span> scattering, it can be extended to invert multicomponent elastic data containing both P- and S-<span class="hlt">wave</span> information.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhPl...24h2113B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhPl...24h2113B"><span>Small amplitude <span class="hlt">waves</span> and linear firehose and mirror instabilities in <span class="hlt">rotating</span> polytropic quantum plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhakta, S.; Prajapati, R. P.; Dolai, B.</p> <p>2017-08-01</p> <p>The small amplitude quantum magnetohydrodynamic (QMHD) <span class="hlt">waves</span> and linear firehose and mirror instabilities in uniformly <span class="hlt">rotating</span> dense quantum plasma have been investigated using generalized polytropic pressure laws. The QMHD model and Chew-Goldberger-Low (CGL) set of equations are used to formulate the basic equations of the problem. The general dispersion relation is derived using normal mode analysis which is discussed in parallel, transverse, and oblique <span class="hlt">wave</span> propagations. The fast, slow, and intermediate QMHD <span class="hlt">wave</span> modes and linear firehose and mirror instabilities are analyzed for isotropic MHD and CGL quantum fluid plasmas. The firehose instability remains unaffected while the mirror instability is modified by polytropic exponents and quantum diffraction parameter. The graphical illustrations show that quantum corrections have a stabilizing influence on the mirror instability. The presence of uniform <span class="hlt">rotation</span> stabilizes while quantum corrections destabilize the growth rate of the system. It is also observed that the growth rate stabilizes much faster in parallel <span class="hlt">wave</span> propagation in comparison to the transverse mode of propagation. The quantum corrections and polytropic exponents also modify the pseudo-MHD and reverse-MHD modes in dense quantum plasma. The phase speed (Friedrichs) diagrams of slow, fast, and intermediate <span class="hlt">wave</span> modes are illustrated for isotropic MHD and double adiabatic MHD or CGL quantum plasmas, where the significant role of magnetic field and quantum diffraction parameters on the phase speed is observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22370541-three-dimensional-structures-equatorial-waves-resulting-super-rotation-atmosphere-tidally-locked-hot-jupiter','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22370541-three-dimensional-structures-equatorial-waves-resulting-super-rotation-atmosphere-tidally-locked-hot-jupiter"><span>Three-dimensional structures of equatorial <span class="hlt">waves</span> and the resulting super-<span class="hlt">rotation</span> in the atmosphere of a tidally locked hot Jupiter</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Tsai, Shang-Min; Gu, Pin-Gao; Dobbs-Dixon, Ian</p> <p></p> <p>Three-dimensional (3D) equatorial trapped <span class="hlt">waves</span> excited by stellar isolation and the resulting equatorial super-<span class="hlt">rotating</span> jet in a vertical stratified atmosphere of a tidally locked hot Jupiter are investigated. Taking the hot Jupiter HD 189733b as a fiducial example, we analytically solve linear equations subject to stationary stellar heating with a uniform zonal-mean flow included. We also extract <span class="hlt">wave</span> information in the final equilibrium state of the atmosphere from our radiative hydrodynamical simulation for HD 189733b. Our analytic <span class="hlt">wave</span> solutions are able to qualitatively explain the 3D simulation results. Apart from previous <span class="hlt">wave</span> studies, investigating the vertical structure of <span class="hlt">waves</span> allowsmore » us to explore new <span class="hlt">wave</span> features such as the wavefronts tilts related to the Rossby-<span class="hlt">wave</span> resonance as well as dispersive equatorial <span class="hlt">waves</span>. We also attempt to apply our linear <span class="hlt">wave</span> analysis to explain some numerical features associated with the equatorial jet development seen in the general circulation model by Showman and Polvani. During the spin-up phase of the equatorial jet, the acceleration of the jet can be in principle boosted by the Rossby-<span class="hlt">wave</span> resonance. However, we also find that as the jet speed increases, the Rossby-<span class="hlt">wave</span> structure shifts eastward, while the Kelvin-<span class="hlt">wave</span> structure remains <span class="hlt">approximately</span> stationary, leading to the decline of the acceleration rate. Our analytic model of jet evolution implies that there exists only one stable equilibrium state of the atmosphere, possibly implying that the final state of the atmosphere is independent of initial conditions in the linear regime. Limitations of our linear model and future improvements are also discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22779638','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22779638"><span>Orbitally invariant internally contracted multireference unitary coupled cluster theory and its perturbative <span class="hlt">approximation</span>: theory and test calculations of second order <span class="hlt">approximation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Zhenhua; Hoffmann, Mark R</p> <p>2012-07-07</p> <p>A unitary <span class="hlt">wave</span> operator, exp (G), G(+) = -G, is considered to transform a multiconfigurational reference <span class="hlt">wave</span> function Φ to the potentially exact, within basis set limit, <span class="hlt">wave</span> function Ψ = exp (G)Φ. To obtain a useful <span class="hlt">approximation</span>, the Hausdorff expansion of the similarity transformed effective Hamiltonian, exp (-G)Hexp (G), is truncated at second order and the excitation manifold is limited; an additional separate perturbation <span class="hlt">approximation</span> can also be made. In the perturbation <span class="hlt">approximation</span>, which we refer to as multireference unitary second-order perturbation theory (MRUPT2), the Hamiltonian operator in the highest order commutator is <span class="hlt">approximated</span> by a Mo̸ller-Plesset-type one-body zero-order Hamiltonian. If a complete active space self-consistent field <span class="hlt">wave</span> function is used as reference, then the energy is invariant under orbital <span class="hlt">rotations</span> within the inactive, active, and virtual orbital subspaces for both the second-order unitary coupled cluster method and its perturbative <span class="hlt">approximation</span>. Furthermore, the redundancies of the excitation operators are addressed in a novel way, which is potentially more efficient compared to the usual full diagonalization of the metric of the excited configurations. Despite the loss of rigorous size-extensivity possibly due to the use of a variational approach rather than a projective one in the solution of the amplitudes, test calculations show that the size-extensivity errors are very small. Compared to other internally contracted multireference perturbation theories, MRUPT2 only needs reduced density matrices up to three-body even with a non-complete active space reference <span class="hlt">wave</span> function when two-body excitations within the active orbital subspace are involved in the <span class="hlt">wave</span> operator, exp (G). Both the coupled cluster and perturbation theory variants are amenable to large, incomplete model spaces. Applications to some widely studied model systems that can be problematic because of geometry dependent quasidegeneracy, H4, P4</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..DPPPP8002P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..DPPPP8002P"><span>Lower Hybrid <span class="hlt">Wave</span> Induced <span class="hlt">Rotation</span> on Alcator C-Mod</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parker, Ron; Podpaly, Yuri; Rice, John; Schmidt, Andrea</p> <p>2009-11-01</p> <p>Injection of RF power in the vicinity of the lower hybrid frequency has been observed to cause strong counter current <span class="hlt">rotation</span> in Alcator C-Mod plasmas [1,2]. The spin-up rate is consistent with the rate at which momentum is injected by the LH <span class="hlt">waves</span>, and also the rate at which fast electron momentum is transferred to the ions. A momentum diffusivity of ˜ 0.1 m^2/s is sufficient to account for the observed steady-state <span class="hlt">rotation</span>. This value is also comparable with that derived from an analysis of <span class="hlt">rotation</span> induced by RF mode conversion [3]. Radial force balance requires a radial electric field, suggesting a buildup of negative charge in the plasma core. This may be the result of an inward pinch of the LH produced fast electrons, as would be expected for resonant trapped particles. Analysis of the fast-electron-produced bremsstrahlung during LH power modulation experiments yields an inward pinch velocity of ˜ 1 m/s, consistent with the estimated trapped particle pinch velocity. [4pt] [1] A. Ince-Cushman, et.al., Phys. Rev. Lett., 102, 035002 (2009)[0pt] [2] J. E. Rice, et. al., Nucl. Fusion 49, 025004 (2009)[0pt] [3] Y. Lin, et.al., this meeting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/491378','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/491378"><span>Reduction of toroidal <span class="hlt">rotation</span> by fast <span class="hlt">wave</span> power in DIII-D</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Grassie, J.S. de; Baker, D.R.; Burrell, K.H.</p> <p>1997-04-01</p> <p>The application of fast <span class="hlt">wave</span> power in DIII-D has proven effective for both electron heating and current drive. Since the last RIF Conference FW power has been applied to advanced confinement regimes in DIII-D; negative central shear (NCS), VH- and H-modes, high {beta}{sub p}, and high-{ell}i. Typically these regimes show enhanced confinement of toroidal momentum exhibited by increased toroidal <span class="hlt">rotation</span> velocity. Indeed, layers of large shear in toroidal velocity are associated with transport barriers. A rather common occurrence in these experiments is that the toroidal <span class="hlt">rotation</span> velocity is decreased when the FW power is turned on, to lowest order independentmore » of whether the antennas are phased for co or counter current drive. At present all the data is for co-injected beams. The central toroidal <span class="hlt">rotation</span> can be reduced to 1/2 of the non-FW level. Here the authors describe the effect in NCS discharges with co-beam injection.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70192481','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70192481"><span><span class="hlt">Rotational</span> seismology</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lee, William H K.</p> <p>2016-01-01</p> <p><span class="hlt">Rotational</span> seismology is an emerging study of all aspects of <span class="hlt">rotational</span> motions induced by earthquakes, explosions, and ambient vibrations. It is of interest to several disciplines, including seismology, earthquake engineering, geodesy, and earth-based detection of Einstein’s gravitation <span class="hlt">waves.Rotational</span> effects of seismic <span class="hlt">waves</span>, together with <span class="hlt">rotations</span> caused by soil–structure interaction, have been observed for centuries (e.g., <span class="hlt">rotated</span> chimneys, monuments, and tombstones). Figure 1a shows the <span class="hlt">rotated</span> monument to George Inglis observed after the 1897 Great Shillong earthquake. This monument had the form of an obelisk rising over 19 metres high from a 4 metre base. During the earthquake, the top part broke off and the remnant of some 6 metres <span class="hlt">rotated</span> about 15° relative to the base. The study of <span class="hlt">rotational</span> seismology began only recently when sensitive <span class="hlt">rotational</span> sensors became available due to advances in aeronautical and astronomical instrumentations.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25318724','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25318724"><span>Effects of reagent <span class="hlt">rotational</span> excitation on the H + CHD₃ → H₂ + CD₃ reaction: a seven dimensional time-dependent <span class="hlt">wave</span> packet study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Zhaojun; Zhang, Dong H</p> <p>2014-10-14</p> <p>Seven-dimensional time-dependent <span class="hlt">wave</span> packet calculations have been carried out for the title reaction to obtain reaction probabilities and cross sections for CHD3 in J0 = 1, 2 <span class="hlt">rotationally</span> excited initial states with k0 = 0 - J0 (the projection of CHD3 <span class="hlt">rotational</span> angular momentum on its C3 axis). Under the centrifugal sudden (CS) <span class="hlt">approximation</span>, the initial states with the projection of the total angular momentum on the body fixed axis (K0) equal to k0 are found to be much more reactive, indicating strong dependence of reactivity on the orientation of the reagent CHD3 with respect to the relative velocity between the reagents H and CHD3. However, at the coupled-channel (CC) level this dependence becomes much weak although in general the K0 specified cross sections for the K0 = k0 initial states remain primary to the overall cross sections, implying the Coriolis coupling is important to the dynamics of the reaction. The calculated CS and CC integral cross sections obtained after K0 averaging for the J0 = 1, 2 initial states with all different k0 are essentially identical to the corresponding CS and CC results for the J0 = 0 initial state, meaning that the initial <span class="hlt">rotational</span> excitation of CHD3 up to J0 = 2, regardless of its initial k0, does not have any effect on the total cross sections for the title reaction, and the errors introduced by the CS <span class="hlt">approximation</span> on integral cross sections for the <span class="hlt">rotationally</span> excited J0 = 1, 2 initial states are the same as those for the J0 = 0 initial state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDG26009K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDG26009K"><span>NOx Emissions from a <span class="hlt">Rotating</span> Detonation-<span class="hlt">wave</span> Engine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kailasanath, Kazhikathra; Schwer, Douglas</p> <p>2016-11-01</p> <p><span class="hlt">Rotating</span> detonation-<span class="hlt">wave</span> engines (RDE) are a form of continuous detonation-<span class="hlt">wave</span> engines. They potentially provide further gains in performance than an intermittent or pulsed detonation-<span class="hlt">wave</span> engine (PDE). The overall flow field in an idealized RDE, primarily consisting of two concentric cylinders, has been discussed in previous meetings. Because of the high pressures involved and the lack of adequate reaction mechanisms for this regime, previous simulations have typically used simplified chemistry models. However, understanding the exhaust species concentrations in propulsion devices is important for both performance considerations as well as estimating pollutant emissions. Progress towards addressing this need will be discussed in this talk. In this approach, an induction parameter model is used for simulating the detonation but a more detailed finite-chemistry model including NOx chemistry is used in the expansion flow region, where the pressures are lower and the uncertainties in the chemistry model are greatly reduced. Results show that overall radical concentrations in the exhaust flow are substantially lower than from earlier predictions with simplified models. Results to date show that NOx emissions are not a problem for the RDE due to the short residence times and the nature of the flow field. Furthermore, simulations show that the amount of NOx can be further reduced by tailoring the fluid dynamics within the RDE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.tmp..106O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.tmp..106O"><span><span class="hlt">Approximate</span> non-linear multiparameter inversion for multicomponent single and double P-<span class="hlt">wave</span> scattering in isotropic elastic media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ouyang, Wei; Mao, Weijian</p> <p>2018-03-01</p> <p>An asymptotic quadratic true-amplitude inversion method for isotropic elastic P <span class="hlt">waves</span> is proposed to invert medium parameters. The multicomponent P-<span class="hlt">wave</span> scattered wavefield is computed based on a forward relationship using second-order Born <span class="hlt">approximation</span> and corresponding high-frequency ray theoretical methods. Within the local double scattering mechanism, the P-<span class="hlt">wave</span> transmission factors are elaborately calculated, which results in the radiation pattern for P-<span class="hlt">waves</span> scattering being a quadratic combination of the density and Lamé's moduli perturbation parameters. We further express the elastic P-<span class="hlt">wave</span> scattered wavefield in a form of generalized Radon transform (GRT). After introducing classical backprojection operators, we obtain an <span class="hlt">approximate</span> solution of the inverse problem by solving a quadratic non-linear system. Numerical tests with synthetic data computed by finite-differences scheme demonstrate that our quadratic inversion can accurately invert perturbation parameters for strong perturbations, compared with the P-<span class="hlt">wave</span> single-scattering linear inversion method. Although our inversion strategy here is only syncretized with P-<span class="hlt">wave</span> scattering, it can be extended to invert multicomponent elastic data containing both P-<span class="hlt">wave</span> and S-<span class="hlt">wave</span> information.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7077169-infinite-order-sudden-approximation-rotational-energy-transfer-gaseous-mixtures','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7077169-infinite-order-sudden-approximation-rotational-energy-transfer-gaseous-mixtures"><span>Infinite order sudden <span class="hlt">approximation</span> for <span class="hlt">rotational</span> energy transfer in gaseous mixtures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Goldflam, R.; Green, S.; Kouri, D.J.</p> <p>1977-11-01</p> <p><span class="hlt">Rotational</span> energy transfer in gaseous mixtures has been considered within the framework of the infinite order sudden (IOS) <span class="hlt">approximation</span>. A new derivation of the IOS from the coupled states Lippmann--Schwinger equation is given. This approach shows the relation between the IOS and CS T matrices and also shows in a rather transparent fashion Sencrest's result that the IOS method does not truncate closed channels but rather employs a closure relation to sum over all rotor states. The general CS effective cross section formula for relaxation processes is used, along with the IOS <span class="hlt">approximation</span> to the CS T matrix, to derivemore » the general IOS effctive cross section.Factorization permits one to calculate other types of cross sections if any one type of cross section has been obtained by some procedure. The functional form can also be used to compact data. This formalism has been applied to calculate pressure broadening for the systems HD--He, HCl--He, CO--He, HCN--He, HCl--Ar, and CO/sub 2/--Ar. To test the IOS <span class="hlt">approximation</span>, comparisons have been made to the CS results, which are known to be accurate for all these systems. The IOS <span class="hlt">approximation</span> is found to be very accurate whenever the rotor spacings are small compared to the kinetic energy, provided closed channels do not play too great a role. For the systems CO--He, HCN--He, and CO/sub 2/--Ar, these conditions are well satisfied and the IOS is found to yield results accurate to within 10%--15%.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4348629','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4348629"><span>Analytical Solution for the Anisotropic Rabi Model: Effects of Counter-<span class="hlt">Rotating</span> Terms</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhang, Guofeng; Zhu, Hanjie</p> <p>2015-01-01</p> <p>The anisotropic Rabi model, which was proposed recently, differs from the original Rabi model: the <span class="hlt">rotating</span> and counter-<span class="hlt">rotating</span> terms are governed by two different coupling constants. This feature allows us to vary the counter-<span class="hlt">rotating</span> interaction independently and explore the effects of it on some quantum properties. In this paper, we eliminate the counter-<span class="hlt">rotating</span> terms <span class="hlt">approximately</span> and obtain the analytical energy spectrums and wavefunctions. These analytical results agree well with the numerical calculations in a wide range of the parameters including the ultrastrong coupling regime. In the weak counter-<span class="hlt">rotating</span> coupling limit we find out that the counter-<span class="hlt">rotating</span> terms can be considered as the shifts to the parameters of the Jaynes-Cummings model. This modification shows the validness of the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span> on the assumption of near-resonance and relatively weak coupling. Moreover, the analytical expressions of several physics quantities are also derived, and the results show the break-down of the U(1)-symmetry and the deviation from the Jaynes-Cummings model. PMID:25736827</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S21A0691B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S21A0691B"><span>Using Co-located <span class="hlt">Rotational</span> and Translational Ground-Motion Sensors to Characterize Seismic Scattering in the P-<span class="hlt">Wave</span> Coda</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bartrand, J.; Abbott, R. E.</p> <p>2017-12-01</p> <p>We present data and analysis of a seismic data collect at the site of a historical underground nuclear explosion at Yucca Flat, a sedimentary basin on the Nevada National Security Site, USA. The data presented here consist of active-source, six degree-of-freedom seismic signals. The translational signals were collected with a Nanometrics Trillium Compact Posthole seismometer and the <span class="hlt">rotational</span> signals were collected with an ATA Proto-SMHD, a prototype <span class="hlt">rotational</span> ground motion sensor. The source for the experiment was the Seismic Hammer (a 13,000 kg weight-drop), deployed on two-kilometer, orthogonal arms centered on the site of the nuclear explosion. By leveraging the fact that compressional <span class="hlt">waves</span> have no <span class="hlt">rotational</span> component, we generated a map of subsurface scattering and compared the results to known subsurface features. To determine scattering intensity, signals were cut to include only the P-<span class="hlt">wave</span> and its coda. The ratio of the time-domain signal magnitudes of angular velocity and translational acceleration were sectioned into three time windows within the coda and averaged within each window. Preliminary results indicate an increased <span class="hlt">rotation</span>/translation ratio in the vicinity of the explosion-generated chimney, suggesting mode conversion of P-<span class="hlt">wave</span> energy to S-<span class="hlt">wave</span> energy at that location. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1512495L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1512495L"><span>Projection operators for the Rossby and Poincare <span class="hlt">waves</span> in a beta-plane <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lebedkina, Anastasia; Ivan, Karpov; Sergej, Leble</p> <p>2013-04-01</p> <p>. The idea to use the polarization relations for the classification of <span class="hlt">waves</span> originated in radio physics in the works of A. A. Novikov. In the theory of the electromagnetic field polarization relations is traditionally included in the analysis of <span class="hlt">wave</span> phenomena. In the theory of acoustic-gravity <span class="hlt">waves</span>, projection operators were introduced in a works of S. B. Leble. The object of study is a four-dimentional vector (components of the velocity, pressure and temperature). Based on these assumptions, we can construct the projection operators for superposition state on the linear basis, corresponding to the well-known type of <span class="hlt">waves</span>. In this paper we consider procedure for construction of a projection operators for planetary Rossby and Poincare <span class="hlt">waves</span> in the Earth's atmosphere in the <span class="hlt">approximation</span> of the "beta-plane". In a result of work we constructed projection operators in this <span class="hlt">approximation</span> for Poincare and Rossby <span class="hlt">waves</span>. The tests for operators shown, that separation of the contribution of corresponding <span class="hlt">waves</span> from source of the <span class="hlt">wave</span> field is possible. Estimation accuracy of the operators and results of applying operators to the data TEC presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhPl...25e2111G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhPl...25e2111G"><span>Two mechanisms of resonance overlapping in excitation of azimuthal surface <span class="hlt">waves</span> by <span class="hlt">rotating</span> relativistic electron beams</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Girka, Igor O.; Pavlenko, Ivan V.; Thumm, Manfred</p> <p>2018-05-01</p> <p>Azimuthal surface <span class="hlt">waves</span> are electromagnetic eigenwaves of cylindrical plasma-filled metallic waveguides with a stationary axial magnetic field. These <span class="hlt">waves</span> with extraordinary polarization can effectively interact with relativistic electron beams <span class="hlt">rotating</span> along large Larmor orbits in the gap, which separates the plasma column from the waveguide wall. Both widening the layer and increasing the beam particle density are demonstrated to cause resonance overlapping seen from the perspective of the growth rate dependence on the effective <span class="hlt">wave</span> number.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFD.R2003K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFD.R2003K"><span>Exhaust Gas Emissions from a <span class="hlt">Rotating</span> Detonation-<span class="hlt">wave</span> Engine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kailasanath, Kazhikathra; Schwer, Douglas</p> <p>2015-11-01</p> <p><span class="hlt">Rotating</span> detonation-<span class="hlt">wave</span> engines (RDE) are a form of continuous detonation-<span class="hlt">wave</span> engines. They potentially provide further gains in performance than an intermittent or pulsed detonation-<span class="hlt">wave</span> engine (PDE). The overall flow field in an idealized RDE, primarily consisting of two concentric cylinders, has been discussed in previous meetings. Because of the high pressures involved and the lack of adequate reaction mechanisms for this regime, previous simulations have typically used simplified chemistry models. However, understanding the exhaust species concentrations in propulsion devices is important for both performance considerations as well as estimating pollutant emissions. Progress towards addressing this need will be discussed in this talk. In this approach, an induction parameter model is used for simulating the detonation but a more detailed finite-chemistry model including NOx chemistry is used in the expansion flow region, where the pressures are lower and the uncertainties in the chemistry model are greatly reduced. Results show that overall radical concentrations in the exhaust flow are substantially lower than from earlier predictions with simplified models. The performance of a baseline hydrogen/air RDE increased from 4940 s to 5000 s with the expansion flow chemistry, due to recombination of radicals and more production of H2O, resulting in additional heat release. Work sponsored by the Office of Naval Research.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15162101','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15162101"><span>Extracorporeal shock <span class="hlt">wave</span> therapy for calcific and noncalcific tendonitis of the <span class="hlt">rotator</span> cuff: a systematic review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Harniman, Elaine; Carette, Simon; Kennedy, Carol; Beaton, Dorcas</p> <p>2004-01-01</p> <p>The authors conducted a systematic review to assess the effectiveness of extracorporeal shock <span class="hlt">wave</span> therapy (ESWT) for the treatment of calcific and noncalcific tendonitis of the <span class="hlt">rotator</span> cuff. Conservative treatment for <span class="hlt">rotator</span> cuff tendonitis includes physiotherapy, nonsteroidal antiinflammatory drugs, and corticosteroid injections. If symptoms persist with conservative treatment, surgery is often considered. Extracorporeal shock <span class="hlt">wave</span> therapy has been suggested as a treatment alternative for chronic <span class="hlt">rotator</span> cuff tendonitis, which may decrease the need for surgery. Articles for this review were identified by electronically searching Medline, EMBASE, Cumulative Index to Nursing & Allied Health Literature (CINAHL), and Evidence Based Medicine (EBM) and hand-screening references. Two reviewers selected the trials that met the inclusion criteria, extracted the data, and assessed the methodological quality of the selected trials. Finally, the strength of scientific evidence was appraised. Evidence was classified as strong, moderate, limited, or conflicting. Sixteen trials met the inclusion criteria. There were only five randomized, controlled trials and all involved chronic (>/=3 months) conditions, three for calcific tendonitis and two for noncalcific tendonitis. For randomized, controlled trials, two (40%) were of high quality, one (33%) for calcific tendonitis and one (50%) for noncalcific tendonitis. The 11 nonrandomized trials included nine that involved calcific tendonitis and two that involved both calcific and noncalcific tendonitis. Common problem areas were sample size, randomization, blinding, treatment provider bias, and outcome measures. There is moderate evidence that high-energy ESWT is effective in treating chronic calcific <span class="hlt">rotator</span> cuff tendonitis when the shock <span class="hlt">waves</span> are focused at the calcified deposit. There is moderate evidence that low-energy ESWT is not effective for treating chronic noncalcific <span class="hlt">rotator</span> cuff tendonitis, although this conclusion is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814511R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814511R"><span>Educing the emission mechanism of internal gravity <span class="hlt">waves</span> in the differentially heat <span class="hlt">rotating</span> annulus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rolland, Joran; Hien, Steffen; Achatz, Ulrich; Borchert, Sebastian; Fruman, Mark</p> <p>2016-04-01</p> <p>Understanding the lifecycle of gravity <span class="hlt">waves</span> is fundamental to a good comprehension of the dynamics of the atmosphere. In this lifecycle, the emission mechanisms may be the most elusive. Indeed, while the emission of gravity <span class="hlt">waves</span> by orography or convection is well understood, the so-called spontaneous emission is still a quite open topic of investigation [1]. This type of emission usually occur very near jet-front systems in the troposphere. In this abstract, we announce our numerical study of the question. Model systems of the atmosphere which can be easily simulated or built in a laboratory have always been an important part of the study of atmospheric dynamics, alongside global simulations, in situ measurements and theory. In the case of the study of the spontaneous emission of gravity <span class="hlt">waves</span> near jet-front systems, the differentially heated <span class="hlt">rotating</span> annulus set up has been proposed and extensively used. It comprises of an annular tank containing water: the inner cylinder is kept at a cold temperature while the outer cylinder is kept at a warm temperature. The whole system is <span class="hlt">rotating</span>. Provided the values of the control parameters (temperature, <span class="hlt">rotation</span> rate, gap between the cylinders, height of water) are well chosen, the resulting flow mimics the troposphere at midlatitudes: it has a jet stream, and a baroclinic lifecycle develops on top of it. A very reasonable ratio of Brunt-Väisälä frequency over <span class="hlt">rotation</span> rate of the system can be obtained, so as to be as close to the atmosphere as possible. Recent experiments as well as earlier numerical simulations in our research group have shown that gravity <span class="hlt">waves</span> are indeed emitted in this set up, in particular near the jet front system of the baroclinic <span class="hlt">wave</span> [2]. After a first experimental stage of characterising the emitted wavepacket, we focused our work on testing hypotheses on the gravity <span class="hlt">wave</span> emission mechanism: we have tested and validated the hypothesis of spontaneous imbalance generated by the flow in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2015/1001/downloads/ofr2015-1001_report.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2015/1001/downloads/ofr2015-1001_report.pdf"><span>Future <span class="hlt">wave</span> and wind projections for United States and United-States-affiliated Pacific Islands</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Storlazzi, Curt D.; Shope, James B.; Erikson, Li H.; Hegermiller, Christine A.; Barnard, Patrick L.</p> <p>2015-01-01</p> <p> throughout the study area during other seasons. Extreme <span class="hlt">wave</span> directions in equatorial Micronesia during June-August undergo an <span class="hlt">approximate</span> 30° clockwise <span class="hlt">rotation</span> from primarily west to northwest. September-November RCP4.5 extreme mean <span class="hlt">wave</span> directions <span class="hlt">rotate</span> counterclockwise by <span class="hlt">approximately</span> 30 to 45° in equatorial Micronesia; September-November RCP8.5 extreme mean <span class="hlt">wave</span> directions within equatorial Micronesia <span class="hlt">rotate</span> clockwise by <span class="hlt">approximately</span> 20 to 30°. Extreme wind speeds decreased within both scenarios, with the largest decreases occurring in the September-November season. Extreme wind directions under RCP4.5 <span class="hlt">rotated</span> clockwise by more than 60° in equatorial Micronesia during the September-November season and by <span class="hlt">approximately</span> 30° during June-August. RCP8.5 extreme wind directions <span class="hlt">rotated</span> counterclockwise during September-November within the same region by 30 to 50° and clockwise by 30 to 40° at one island. The spatial patterns and trends are similar between the two different greenhouse gas emission scenarios, with the magnitude and extent of the trends generally greater for the higher (RCP8.5) scenario.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5750529','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5750529"><span>Optimization of a Focusable and <span class="hlt">Rotatable</span> Shear-<span class="hlt">Wave</span> Periodic Permanent Magnet Electromagnetic Acoustic Transducers for Plates Inspection</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Qiu, Gongzhe</p> <p>2017-01-01</p> <p>Due to the symmetry of conventional periodic-permanent-magnet electromagnetic acoustic transducers (PPM EMATs), two shear (SH) <span class="hlt">waves</span> can be generated and propagated simultaneously in opposite directions, which makes the signal recognition and interpretation complicatedly. Thus, this work presents a new SH <span class="hlt">wave</span> PPM EMAT design, <span class="hlt">rotating</span> the parallel line sources to realize the <span class="hlt">wave</span> beam focusing in a single-direction. The theoretical model of distributed line sources was deduced firstly, and the effects of some parameters, such as the inner coil width, adjacent line sources spacing and the angle between parallel line sources, on SH <span class="hlt">wave</span> focusing and directivity were studied mainly with the help of 3D FEM. Employing the proposed PPM EMATs, some experiments are carried out to verify the reliability of FEM simulation. The results indicate that <span class="hlt">rotating</span> the parallel line sources can strength the <span class="hlt">wave</span> on the closing side of line sources, decreasing the inner coil width and the adjacent line sources spacing can improve the amplitude and directivity of signals excited by transducers. Compared with traditional PPM EMATs, both the capacity of unidirectional excitation and directivity of the proposed PPM EMATs are improved significantly. PMID:29186790</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29186790','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29186790"><span>Optimization of a Focusable and <span class="hlt">Rotatable</span> Shear-<span class="hlt">Wave</span> Periodic Permanent Magnet Electromagnetic Acoustic Transducers for Plates Inspection.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Song, Xiaochun; Qiu, Gongzhe</p> <p>2017-11-24</p> <p>Due to the symmetry of conventional periodic-permanent-magnet electromagnetic acoustic transducers (PPM EMATs), two shear (SH) <span class="hlt">waves</span> can be generated and propagated simultaneously in opposite directions, which makes the signal recognition and interpretation complicatedly. Thus, this work presents a new SH <span class="hlt">wave</span> PPM EMAT design, <span class="hlt">rotating</span> the parallel line sources to realize the <span class="hlt">wave</span> beam focusing in a single-direction. The theoretical model of distributed line sources was deduced firstly, and the effects of some parameters, such as the inner coil width, adjacent line sources spacing and the angle between parallel line sources, on SH <span class="hlt">wave</span> focusing and directivity were studied mainly with the help of 3D FEM. Employing the proposed PPM EMATs, some experiments are carried out to verify the reliability of FEM simulation. The results indicate that <span class="hlt">rotating</span> the parallel line sources can strength the <span class="hlt">wave</span> on the closing side of line sources, decreasing the inner coil width and the adjacent line sources spacing can improve the amplitude and directivity of signals excited by transducers. Compared with traditional PPM EMATs, both the capacity of unidirectional excitation and directivity of the proposed PPM EMATs are improved significantly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013HEDP....9..722K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013HEDP....9..722K"><span>Correction of the near threshold behavior of electron collisional excitation cross-sections in the plane-<span class="hlt">wave</span> Born <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kilcrease, D. P.; Brookes, S.</p> <p>2013-12-01</p> <p>The modeling of NLTE plasmas requires the solution of population rate equations to determine the populations of the various atomic levels relevant to a particular problem. The equations require many cross sections for excitation, de-excitation, ionization and recombination. A simple and computational fast way to calculate electron collisional excitation cross-sections for ions is by using the plane-<span class="hlt">wave</span> Born <span class="hlt">approximation</span>. This is essentially a high-energy <span class="hlt">approximation</span> and the cross section suffers from the unphysical problem of going to zero near threshold. Various remedies for this problem have been employed with varying degrees of success. We present a correction procedure for the Born cross-sections that employs the Elwert-Sommerfeld factor to correct for the use of plane <span class="hlt">waves</span> instead of Coulomb <span class="hlt">waves</span> in an attempt to produce a cross-section similar to that from using the more time consuming Coulomb Born <span class="hlt">approximation</span>. We compare this new <span class="hlt">approximation</span> with other, often employed correction procedures. We also look at some further modifications to our Born Elwert procedure and its combination with Y.K. Kim's correction of the Coulomb Born <span class="hlt">approximation</span> for singly charged ions that more accurately <span class="hlt">approximate</span> convergent close coupling calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6832226-rainbows-rotationally-inelastic-scattering-comparative-study-different-model-potential-surfaces-dynamical-approximations','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6832226-rainbows-rotationally-inelastic-scattering-comparative-study-different-model-potential-surfaces-dynamical-approximations"><span>Rainbows in <span class="hlt">rotationally</span> inelastic scattering: a comparative study of different model potential surfaces and dynamical <span class="hlt">approximations</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Schinke, R.; Korsch, H.J.; Poppe, D.</p> <p>1982-12-15</p> <p>Rainbow structures in <span class="hlt">rotationally</span> elastic and inelastic differential cross sections in atom--diatom collisions are investigated by comparison of three model potential energy surfaces labeled I, II, and III which are represented by V(R,..gamma..) = V/sub 0/(R)+V/sub 2/(R)P/sub 2/(cos ..gamma..). The cross sections are calculated within the quantal infinite-order-sudden (IOS) <span class="hlt">approximation</span>. The anisotropic part V/sub 2/ is the same for all potentials and purely repulsive. The isotropic part V/sub 0/ for potential I is also repulsive and the differential cross sections show the well-studied <span class="hlt">rotational</span> rainbow structures. Structural changes occur for collisions in potential II and III which have V/sub 0/more » terms being attractive at intermediate and large atom--molecule separations and having well depths of 10% and 25% of the collision energy, respectively. For example, the elastic cross section has no classical rainbow in the case of potential I but three in the case of potential III. The rainbow structures are analyzed within the classical and semiclassical versions of the IOS <span class="hlt">approximation</span> and interpreted in terms of catastrophe theory. The quantitative comparison of the classical with the quantal IOS cross sections manifests possible quantum effects, i.e., tunneling into nonclassical regions and interference effects due to the superposition of several contributions (up to six in the present study). They can be very prominent and thus we conclude that much caution is needed if experimental data are compared with classical calculations. The accuracy of the IOS <span class="hlt">approximation</span> is tested by comparison of classical IOS cross sections with cross sections obtained from exact classical trajectory calculations. The agreement is generally good with the exemption of the rainbow region and small angle, <span class="hlt">rotationally</span> elastic scattering.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5593141','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5593141"><span>Feasibility Assessment of Shear <span class="hlt">Wave</span> Elastography to <span class="hlt">Rotator</span> Cuff Muscle</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Itoigawa, Yoshiaki; Sperling, John W.; Steinmann, Scott P.; Chen, Qingshan; Song, Pengfei; Chen, Shigao; Itoi, Eiji; Hatta, Taku; An, Kai-Nan</p> <p>2017-01-01</p> <p>Introduction Pre -surgical measurement of supraspinatus muscle extensibility would be important for <span class="hlt">rotator</span> cuff repair. The purpose of the present study was to explore the potential feasibility of a shear <span class="hlt">wave</span> ultrasound electrograph (SWE) based method, combined with B-mode ultrasound, to non-invasively measure in vivo stiffness of supraspinatus muscle, and thus obtaining the key information on supraspinatus muscle extensibility. Materials and Methods Our investigation consisted of 2 steps. First, we evaluated orientation of the supraspinatus muscle fiber on cadaveric shoulders without <span class="hlt">rotator</span> cuff tear in order to optimize the ultrasound probe positions for SWE imaging. Second, we investigated the feasibility of quantifying the normal supraspinatus muscle stiffness by SWE in vivo. Results The supraspinatus muscle was divided into four anatomical regions, namely anterior superficial (AS), posterior superficial (PS), anterior deep (AD) and posterior deep (PD) regions. SWE was evaluated at each of these regions. SWE stiffness on AD, AS, PD, and PS were measured as 40.0±12.4, 34.0±9.9, 32.7±12.7, 39.1±15.7 kPa, respectively. Conclusions SWE combined with B-Mode ultrasound image may be a feasible method to quantify local tissue stiffness of the <span class="hlt">rotator</span> cuff muscles. PMID:25557287</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28617509','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28617509"><span>Controlled <span class="hlt">rotation</span> and translation of spherical particles or living cells by surface acoustic <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bernard, Ianis; Doinikov, Alexander A; Marmottant, Philippe; Rabaud, David; Poulain, Cédric; Thibault, Pierre</p> <p>2017-07-11</p> <p>We show experimental evidence of the acoustically-assisted micromanipulation of small objects like solid particles or blood cells, combining <span class="hlt">rotation</span> and translation, using high frequency surface acoustic <span class="hlt">waves</span>. This was obtained from the leakage in a microfluidic channel of two standing <span class="hlt">waves</span> arranged perpendicularly in a LiNbO 3 piezoelectric substrate working at 36.3 MHz. By controlling the phase lag between the emitters, we could, in addition to translation, generate a swirling motion of the emitting surface which, in turn, led to the rapid <span class="hlt">rotation</span> of spherical polystyrene Janus beads suspended in the channel and of human red and white blood cells up to several rounds per second. We show that these revolution velocities are compatible with a torque caused by the acoustic streaming that develops at the particles surface, like that first described by [F. Busse et al., J. Acoust. Soc. Am., 1981, 69(6), 1634-1638]. This device, based on standard interdigitated transducers (IDTs) adjusted to emit at equal frequencies, opens a way to a large range of applications since it allows the simultaneous control of the translation and <span class="hlt">rotation</span> of hard objects, as well as the investigation of the response of cells to shear stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28597729','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28597729"><span>Effects of high- and low-energy radial shock <span class="hlt">waves</span> therapy combined with physiotherapy in the treatment of <span class="hlt">rotator</span> cuff tendinopathy: a retrospective study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Su, Xiangzheng; Li, Zhongli; Liu, Zhengsheng; Shi, Teng; Xue, Chao</p> <p>2017-06-09</p> <p>The aim of this study was to investigate the efficacy of high- and low-energy radial shock <span class="hlt">waves</span> combined with physiotherapy for <span class="hlt">rotator</span> cuff tendinopathy patients. Data from <span class="hlt">rotator</span> cuff tendinopathy patients received high- or low-energy radial shock <span class="hlt">waves</span> combined with physiotherapy or physiotherapy alone were collected. The Constant and Murley score and visual analog scale score were collected to assess the effectiveness of treatment in three groups at 4, 8, 12, and 24 weeks. In total, 94 patients were involved for our retrospective study. All groups showed remarkable improvement in the visual analog scale and Constant and Murley score compared to baseline at 24 weeks. The high-energy radial shock <span class="hlt">waves</span> group had more marked improvement in the Constant and Murley score compared to the physiotherapy group at 4 and 8 weeks and at 4 weeks when compared with low-energy group. Furthermore, high-energy radial shock <span class="hlt">waves</span> group had superior results on the visual analog scale at 4, 8, and 12 weeks compared to low-energy and physiotherapy groups. This retrospective study supported the usage of high-energy radial shock <span class="hlt">waves</span> as a supplementary therapy over physiotherapy alone for <span class="hlt">rotator</span> cuff tendinopathy by relieving the symptoms rapidly and maintaining symptoms at a satisfactory level for 24 weeks. Implications for Rehabilitation High-energy radial shock <span class="hlt">waves</span> can be a supplemental therapy to physiotherapy for <span class="hlt">rotator</span> cuff tendinopathy. We recommend the usage of high-energy radial shock <span class="hlt">waves</span> during the first 5 weeks, at an interval of 7 days, of physiotherapy treatment. High-energy radial shock <span class="hlt">waves</span> treatment combined with physiotherapy can benefit <span class="hlt">rotator</span> cuff tendinopathy by relieving symptoms rapidly and maintain these improvements at a satisfactory level for quite a long time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG13A..05P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG13A..05P"><span><span class="hlt">Wave</span> theory in <span class="hlt">rotating</span> systems: Schrödinger equations bridge the gaps between the equatorial β-plane and the spherical earth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paldor, N.</p> <p>2017-12-01</p> <p>The concise and elegant <span class="hlt">wave</span> theory developed on the equatorial β-plane by Matsuno (1966, M66 hereafter) is based on the formulation of a Schrödinger equation associated with the governing Linear <span class="hlt">Rotating</span> Shallow Water Equations (LRSWE). The theory yields explicit expressions for the dispersion relations and meridional amplitude structures of all zonally propagating <span class="hlt">waves</span> - Rossby, Inertia-Gravity, Kelvin and Yanai. In contrast, the spherical <span class="hlt">wave</span> theory of Longuet-Higgins (1968) is a collection of asymptotic expansions in many sub-ranges e.g. large, small (and even negative) Lamb Number; high and low frequency; low-latitudes, etc. that rests upon extensive numerical solutions of several Ordinary Differential Equations. The difference between the two theories is highlighted by their lengths. The essential elements of the former planar study are completely revealed in just 3-4 pages including the derivation of explicit formulae for the phase speeds and amplitude meridional structures. In comtrast, the latter spherical theory contains 97 pages and the results of the numerical calculations are summarized in 30 pages of tables filled with numerical values and about 31 figures, each of which containing many separate curves! In my talk I will re-visit the <span class="hlt">wave</span> problem on a sphere by developing several Schrödinger equations that <span class="hlt">approximate</span> the governing eigenvalue equation associated with zonally propagating <span class="hlt">waves</span>. Each of the Schrödinger equations <span class="hlt">approximates</span> the original second order Ordinary Differential Equation in a different range of the 3 parameters: Lamb-Number, frequency and zonal wavenumber. As in M66, each of the Schrödinger equations yields explicit expressions for the dispersion relations and meridional amplitude structure of Rossby and Inertia-Gravity <span class="hlt">waves</span>. In addition, the analysis shows that Yanai <span class="hlt">wave</span> exists on a sphere even tough the zonal velocity is regular everywhere there (in contrast to the β-plane where the zonal velocity is singular</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1215554V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1215554V"><span>Multivariate statistical data analysis methods for detecting baroclinic <span class="hlt">wave</span> interactions in the thermally driven <span class="hlt">rotating</span> annulus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>von Larcher, Thomas; Harlander, Uwe; Alexandrov, Kiril; Wang, Yongtai</p> <p>2010-05-01</p> <p>Experiments on baroclinic <span class="hlt">wave</span> instabilities in a <span class="hlt">rotating</span> cylindrical gap have been long performed, e.g., to unhide regular <span class="hlt">waves</span> of different zonal <span class="hlt">wave</span> number, to better understand the transition to the quasi-chaotic regime, and to reveal the underlying dynamical processes of complex <span class="hlt">wave</span> flows. We present the application of appropriate multivariate data analysis methods on time series data sets acquired by the use of non-intrusive measurement techniques of a quite different nature. While the high accurate Laser-Doppler-Velocimetry (LDV ) is used for measurements of the radial velocity component at equidistant azimuthal positions, a high sensitive thermographic camera measures the surface temperature field. The measurements are performed at particular parameter points, where our former studies show that kinds of complex <span class="hlt">wave</span> patterns occur [1, 2]. Obviously, the temperature data set has much more information content as the velocity data set due to the particular measurement techniques. Both sets of time series data are analyzed by using multivariate statistical techniques. While the LDV data sets are studied by applying the Multi-Channel Singular Spectrum Analysis (M - SSA), the temperature data sets are analyzed by applying the Empirical Orthogonal Functions (EOF ). Our goal is (a) to verify the results yielded with the analysis of the velocity data and (b) to compare the data analysis methods. Therefor, the temperature data are processed in a way to become comparable to the LDV data, i.e. reducing the size of the data set in such a manner that the temperature measurements would imaginary be performed at equidistant azimuthal positions only. This approach initially results in a great loss of information. But applying the M - SSA to the reduced temperature data sets enable us to compare the methods. [1] Th. von Larcher and C. Egbers, Experiments on transitions of baroclinic <span class="hlt">waves</span> in a differentially heated <span class="hlt">rotating</span> annulus, Nonlinear Processes in Geophysics</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyU...60..843B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyU...60..843B"><span>Gravitational <span class="hlt">waves</span> and core-collapse supernovae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bisnovatyi-Kogan, G. S.; Moiseenko, S. G.</p> <p>2017-11-01</p> <p>A mechanism of formation of gravitational <span class="hlt">waves</span> in the Universe is considered for a nonspherical collapse of matter. Nonspherical collapse results are presented for a uniform spheroid of dust and a finite-entropy spheroid. Numerical simulation results on core-collapse supernova explosions are presented for the neutrino and magneto-<span class="hlt">rotational</span> models. These results are used to estimate the dimensionless amplitude of the gravitational <span class="hlt">wave</span> with a frequency ν ~ 1300 Hz, radiated during the collapse of the <span class="hlt">rotating</span> core of a pre-supernova with a mass of 1.2 M⊙ (calculated by the authors in 2D). This estimate agrees well with many other calculations (presented in this paper) that have been done in 2D and 3D settings and which rely on more exact and sophisticated calculations of the gravitational <span class="hlt">wave</span> amplitude. The formation of the large-scale structure of the Universe in the Zel’dovich pancake model involves the emission of very long-wavelength gravitational <span class="hlt">waves</span>. The average amplitude of these <span class="hlt">waves</span> is calculated from the simulation, in the uniform spheroid <span class="hlt">approximation</span>, of the nonspherical collapse of noncollisional dust matter, which imitates dark matter. It is noted that a gravitational <span class="hlt">wave</span> radiated during a core-collapse supernova explosion in our Galaxy has a sufficient amplitude to be detected by existing gravitational <span class="hlt">wave</span> telescopes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1235662-correction-near-threshold-behavior-electron-collisional-excitation-cross-sections-plane-wave-born-approximation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1235662-correction-near-threshold-behavior-electron-collisional-excitation-cross-sections-plane-wave-born-approximation"><span>Correction of the near threshold behavior of electron collisional excitation cross-sections in the plane-<span class="hlt">wave</span> Born <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Kilcrease, D. P.; Brookes, S.</p> <p>2013-08-19</p> <p>The modeling of NLTE plasmas requires the solution of population rate equations to determine the populations of the various atomic levels relevant to a particular problem. The equations require many cross sections for excitation, de-excitation, ionization and recombination. Additionally, a simple and computational fast way to calculate electron collisional excitation cross-sections for ions is by using the plane-<span class="hlt">wave</span> Born <span class="hlt">approximation</span>. This is essentially a high-energy <span class="hlt">approximation</span> and the cross section suffers from the unphysical problem of going to zero near threshold. Various remedies for this problem have been employed with varying degrees of success. We present a correction procedure formore » the Born cross-sections that employs the Elwert–Sommerfeld factor to correct for the use of plane <span class="hlt">waves</span> instead of Coulomb <span class="hlt">waves</span> in an attempt to produce a cross-section similar to that from using the more time consuming Coulomb Born <span class="hlt">approximation</span>. We compare this new <span class="hlt">approximation</span> with other, often employed correction procedures. Furthermore, we also look at some further modifications to our Born Elwert procedure and its combination with Y.K. Kim's correction of the Coulomb Born <span class="hlt">approximation</span> for singly charged ions that more accurately <span class="hlt">approximate</span> convergent close coupling calculations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.tmp.1297Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.tmp.1297Z"><span>High mode magnetohydrodynamic <span class="hlt">waves</span> propagation in a twisted <span class="hlt">rotating</span> jet emerging from a filament eruption</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhelyazkov, Ivan; Chandra, Ramesh</p> <p>2018-05-01</p> <p>We study the conditions under which high mode magnetohydrodynamic (MHD) <span class="hlt">waves</span> propagating on a <span class="hlt">rotating</span> jet emerging from the filament eruption on 2013 April 10-11 can became unstable against the Kelvin-Helmholtz instability (KHI). The evolution of jet indicates the blob like structure at its boundary which could be one of the observable features of the KHI development. We model the jet as a twisted <span class="hlt">rotating</span> axially moving magnetic flux tube and explore the propagation characteristics of the running MHD modes on the basis of dispersion relations derived in the framework of the ideal magnetohydrodynamics. It is established that unstable MHD <span class="hlt">waves</span> with wavelengths in the range of 12-15 Mm and instability developing times from 1.5 to 2.6 min can be detected at the excitation of high mode MHD <span class="hlt">waves</span>. The magnitude of the azimuthal mode number m crucially depends upon the twist of the internal magnetic field. It is found that at slightly twisted magnetic flux tube the appropriate azimuthal mode number is m = 16 while in the case of a moderately twisted flux tube it is equal to 18.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006A%26A...457..209O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006A%26A...457..209O"><span>Axisymmetric simulations of magnetorotational core collapse: <span class="hlt">approximate</span> inclusion of general relativistic effects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Obergaulinger, M.; Aloy, M. A.; Dimmelmeier, H.; Müller, E.</p> <p>2006-10-01</p> <p>We continue our investigations of the magnetorotational collapse of stellar cores by discussing simulations performed with a modified Newtonian gravitational potential that mimics general relativistic effects. The <span class="hlt">approximate</span> TOV gravitational potential used in our simulations captures several basic features of fully relativistic simulations quite well. In particular, it is able to correctly reproduce the behavior of models that show a qualitative change both of the dynamics and the gravitational <span class="hlt">wave</span> signal when switching from Newtonian to fully relativistic simulations. For models where the dynamics and gravitational <span class="hlt">wave</span> signals are already captured qualitatively correctly by a Newtonian potential, the results of the Newtonian and the <span class="hlt">approximate</span> TOV models differ quantitatively. The collapse proceeds to higher densities with the <span class="hlt">approximate</span> TOV potential, allowing for a more efficient amplification of the magnetic field by differential <span class="hlt">rotation</span>. The strength of the saturation fields (˜ 1015 ~ G at the surface of the inner core) is a factor of two to three higher than in Newtonian gravity. Due to the more efficient field amplification, the influence of magnetic fields is considerably more pronounced than in the Newtonian case for some of the models. As in the Newtonian case, sufficiently strong magnetic fields slow down the core's <span class="hlt">rotation</span> and trigger a secular contraction phase to higher densities. More clearly than in Newtonian models, the collapsed cores of these models exhibit two different kinds of shock generation. Due to magnetic braking, a first shock <span class="hlt">wave</span> created during the initial centrifugal bounce at subnuclear densities does not suffice for ejecting any mass, and the temporarily stabilized core continues to collapse to supranuclear densities. Another stronger shock <span class="hlt">wave</span> is generated during the second bounce as the core exceeds nuclear matter density. The gravitational <span class="hlt">wave</span> signal of these models does not fit into the standard classification</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18764085','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18764085"><span>Modeling shock <span class="hlt">waves</span> in an ideal gas: combining the Burnett <span class="hlt">approximation</span> and Holian's conjecture.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>He, Yi-Guang; Tang, Xiu-Zhang; Pu, Yi-Kang</p> <p>2008-07-01</p> <p>We model a shock <span class="hlt">wave</span> in an ideal gas by combining the Burnett <span class="hlt">approximation</span> and Holian's conjecture. We use the temperature in the direction of shock propagation rather than the average temperature in the Burnett transport coefficients. The shock <span class="hlt">wave</span> profiles and shock thickness are compared with other theories. The results are found to agree better with the nonequilibrium molecular dynamics (NEMD) and direct simulation Monte Carlo (DSMC) data than the Burnett equations and the modified Navier-Stokes theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22415958-communication-creation-molecular-vibrational-motions-via-rotation-vibration-coupling','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22415958-communication-creation-molecular-vibrational-motions-via-rotation-vibration-coupling"><span>Communication: Creation of molecular vibrational motions via the <span class="hlt">rotation</span>-vibration coupling</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Shu, Chuan-Cun; School of Engineering and Information Technology, University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600; Henriksen, Niels E., E-mail: neh@kemi.dtu.dk</p> <p>2015-06-14</p> <p>Building on recent advances in the <span class="hlt">rotational</span> excitation of molecules, we show how the effect of <span class="hlt">rotation</span>-vibration coupling can be switched on in a controlled manner and how this coupling unfolds in real time after a pure <span class="hlt">rotational</span> excitation. We present the first examination of the vibrational motions which can be induced via the <span class="hlt">rotation</span>-vibration coupling after a pulsed <span class="hlt">rotational</span> excitation. A time-dependent quantum <span class="hlt">wave</span> packet calculation for the HF molecule shows how a slow (compared to the vibrational period) <span class="hlt">rotational</span> excitation leads to a smooth increase in the average bond length whereas a fast <span class="hlt">rotational</span> excitation leads to amore » non-stationary vibrational motion. As a result, under field-free postpulse conditions, either a stretched stationary bond or a vibrating bond can be created due to the coupling between the <span class="hlt">rotational</span> and vibrational degrees of freedom. The latter corresponds to a laser-induced breakdown of the adiabatic <span class="hlt">approximation</span> for <span class="hlt">rotation</span>-vibration coupling.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28740187','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28740187"><span>Dark state with counter-<span class="hlt">rotating</span> dissipative channels.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Zheng-Yang; Chen, Mi; Wu, Lian-Ao; Yu, Ting; You, J Q</p> <p>2017-07-24</p> <p>Dark state as a consequence of interference between different quantum states has great importance in the fields of chip-scale atomic clock and quantum information. For the Λ-type three-level system, this dark state is generally regarded as being dissipation-free because it is a superposition of two lowest states without dipole transition between them. However, previous studies are based on the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span> (RWA) by neglecting the counter-<span class="hlt">rotating</span> terms in the system-environment interaction. In this work, we study non-Markovian quantum dynamics of the dark state in a Λ-type three-level system coupled to two bosonic baths and reveal the effect of counter-<span class="hlt">rotating</span> terms on the dark state. In contrast to the dark state within the RWA, leakage of the dark state occurs even at zero temperature, as a result of these counter-<span class="hlt">rotating</span> terms. Also, we present a method to restore the quantum coherence of the dark state by applying a leakage elimination operator to the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850058285&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Brotor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850058285&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Brotor"><span>The exact eigenfunctions and eigenvalues of a two-dimensional rigid rotor obtained using Gaussian <span class="hlt">wave</span> packet dynamics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Reimers, J. R.; Heller, E. J.</p> <p>1985-01-01</p> <p>Exact eigenfunctions for a two-dimensional rigid rotor are obtained using Gaussian <span class="hlt">wave</span> packet dynamics. The <span class="hlt">wave</span> functions are obtained by propagating, without <span class="hlt">approximation</span>, an infinite set of Gaussian <span class="hlt">wave</span> packets that collectively have the correct periodicity, being coherent states appropriate to this <span class="hlt">rotational</span> problem. This result leads to a numerical method for the semiclassical calculation of rovibrational, molecular eigenstates. Also, a simple, almost classical, <span class="hlt">approximation</span> to full <span class="hlt">wave</span> packet dynamics is shown to give exact results: this leads to an a posteriori justification of the De Leon-Heller spectral quantization method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JNS....10..569L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JNS....10..569L"><span>Translational Symmetry-Breaking for Spiral <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>LeBlanc, V. G.; Wulff, C.</p> <p>2000-10-01</p> <p>Spiral <span class="hlt">waves</span> are observed in numerous physical situations, ranging from Belousov-Zhabotinsky (BZ) chemical reactions, to cardiac tissue, to slime-mold aggregates. Mathematical models with Euclidean symmetry have recently been developed to describe the dynamic behavior (for example, meandering) of spiral <span class="hlt">waves</span> in excitable media. However, no physical experiment is ever infinite in spatial extent, so the Euclidean symmetry is only <span class="hlt">approximate</span>. Experiments on spiral <span class="hlt">waves</span> show that inhomogeneities can anchor spirals and that boundary effects (for example, boundary drifting) become very important when the size of the spiral core is comparable to the size of the reacting medium. Spiral anchoring and boundary drifting cannot be explained by the Euclidean model alone. In this paper, we investigate the effects on spiral <span class="hlt">wave</span> dynamics of breaking the translation symmetry while keeping the <span class="hlt">rotation</span> symmetry. This is accomplished by introducing a small perturbation in the five-dimensional center bundle equations (describing Hopf bifurcation from one-armed spiral <span class="hlt">waves</span>) which is SO(2)-equivariant but not equivariant under translations. We then study the effects of this perturbation on rigid spiral <span class="hlt">rotation</span>, on quasi-periodic meandering and on drifting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820058437&hterms=carbon+emissions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcarbon%2Bemissions','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820058437&hterms=carbon+emissions&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcarbon%2Bemissions"><span>Far-infrared <span class="hlt">rotational</span> emission by carbon monoxide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mckee, C. F.; Storey, J. W. V.; Watson, D. M.; Green, S.</p> <p>1982-01-01</p> <p>Accurate theoretical collisional excitation rates are used to determine the emissivities of CO <span class="hlt">rotational</span> lines for an H2 molecule content of at least 10,000/cu cm, temperature in the range 100-3000 K, and J not more than 60 under the assumption that the lines are optically thin. An <span class="hlt">approximate</span> analytic expression for the emissivities which is valid in this region is obtained. Population inversions in the lower <span class="hlt">rotational</span> levels occur for densities of molecular H2 around 1000-100,000/cu cm and temperatures T not more than about 50 K provided photon trapping is unimportant. Interstellar shocks observed edge-on are a potential source of weak millimeter-<span class="hlt">wave</span> CO maser emission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.2576S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.2576S"><span>Seismic shear <span class="hlt">waves</span> as Foucault pendulum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Snieder, Roel; Sens-Schönfelder, Christoph; Ruigrok, Elmer; Shiomi, Katsuhiko</p> <p>2016-03-01</p> <p>Earth's <span class="hlt">rotation</span> causes splitting of normal modes. <span class="hlt">Wave</span> fronts and rays are, however, not affected by Earth's <span class="hlt">rotation</span>, as we show theoretically and with observations made with USArray. We derive that the Coriolis force causes a small transverse component for P <span class="hlt">waves</span> and a small longitudinal component for S <span class="hlt">waves</span>. More importantly, Earth's <span class="hlt">rotation</span> leads to a slow <span class="hlt">rotation</span> of the transverse polarization of S <span class="hlt">waves</span>; during the propagation of S <span class="hlt">waves</span> the particle motion behaves just like a Foucault pendulum. The polarization plane of shear <span class="hlt">waves</span> counteracts Earth's <span class="hlt">rotation</span> and <span class="hlt">rotates</span> clockwise in the Northern Hemisphere. The <span class="hlt">rotation</span> rate is independent of the <span class="hlt">wave</span> frequency and is purely geometric, like the Berry phase. Using the polarization of ScS and ScS2 <span class="hlt">waves</span>, we show that the Foucault-like <span class="hlt">rotation</span> of the S <span class="hlt">wave</span> polarization can be observed. This can affect the determination of source mechanisms and the interpretation of observed SKS splitting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11008796','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11008796"><span>On <span class="hlt">approximating</span> guided <span class="hlt">waves</span> in plates with thin anisotropic coatings by means of effective boundary conditions</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Niklasson; Datta; Dunn</p> <p>2000-09-01</p> <p>In this paper, effective boundary conditions for elastic <span class="hlt">wave</span> propagation in plates with thin coatings are derived. These effective boundary conditions are used to obtain an <span class="hlt">approximate</span> dispersion relation for guided <span class="hlt">waves</span> in an isotropic plate with thin anisotropic coating layers. The accuracy of the effective boundary conditions is investigated numerically by comparison with exact solutions for two different material systems. The systems considered consist of a metallic core with thin superconducting coatings. It is shown that for wavelengths long compared to the coating thickness there is excellent agreement between the <span class="hlt">approximate</span> and exact solutions for both systems. Furthermore, numerical results presented might be used to characterize coating properties by ultrasonic techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3927208','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3927208"><span>Arbitrary photonic <span class="hlt">wave</span> plate operations on chip: Realizing Hadamard, Pauli-X, and <span class="hlt">rotation</span> gates for polarisation qubits</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Heilmann, René; Gräfe, Markus; Nolte, Stefan; Szameit, Alexander</p> <p>2014-01-01</p> <p>Chip-based photonic quantum computing is an emerging technology that promises much speedup over conventional computers at small integration volumes. Particular interest is thereby given to polarisation-encoded photonic qubits, and many protocols have been developed for this encoding. However, arbitrary <span class="hlt">wave</span> plate operation on chip are not available so far, preventing from the implementation of integrated universal quantum computing algorithms. In our work we close this gap and present Hadamard, Pauli-X, and <span class="hlt">rotation</span> gates of high fidelity for photonic polarisation qubits on chip by employing a reorientation of the optical axis of birefringent waveguides. The optical axis of the birefringent waveguide is <span class="hlt">rotated</span> due to the impact of an artificial stress field created by an additional modification close to the waveguide. By adjusting this length of the defect along the waveguide, the retardation between ordinary and extraordinary field components is precisely tunable including half-<span class="hlt">wave</span> plate and quarter-<span class="hlt">wave</span> plate operations. Our approach demonstrates the full range control of orientation and strength of the induced birefringence and thus allows arbitrary <span class="hlt">wave</span> plate operations without affecting the degree of polarisation or introducing additional losses to the waveguides. The implemented gates are tested with classical and quantum light. PMID:24534893</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT.......106K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT.......106K"><span>Nonlinear Dispersive Elastic <span class="hlt">Waves</span> in Solids: Exact, <span class="hlt">Approximate</span>, and Numerical Solutions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khajehtourian, Romik</p> <p></p> <p> extended method, which is based on a standard transfer-matrix formulation augmented with a nonlinear enrichment at the constitutive material level, yields an <span class="hlt">approximate</span> band structure that is accurate to an amplitude that is roughly one eighth of the unit cell length. This approach represents a new paradigm for examining the balance between periodicity and nonlinearity in shaping the nature of <span class="hlt">wave</span> motion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT........16N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT........16N"><span>Visualizing, <span class="hlt">Approximating</span>, and Understanding Black-Hole Binaries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nichols, David A.</p> <p></p> <p>Numerical-relativity simulations of black-hole binaries and advancements in gravitational-<span class="hlt">wave</span> detectors now make it possible to learn more about the collisions of compact astrophysical bodies. To be able to infer more about the dynamical behavior of these objects requires a fuller analysis of the connection between the dynamics of pairs of black holes and their emitted gravitational <span class="hlt">waves</span>. The chapters of this thesis describe three approaches to learn more about the relationship between the dynamics of black-hole binaries and their gravitational <span class="hlt">waves</span>: modeling momentum flow in binaries with the Landau-Lifshitz formalism, <span class="hlt">approximating</span> binary dynamics near the time of merger with post-Newtonian and black-hole-perturbation theories, and visualizing spacetime curvature with tidal tendexes and frame-drag vortexes. In Chapters 2--4, my collaborators and I present a method to quantify the flow of momentum in black-hole binaries using the Landau-Lifshitz formalism. Chapter 2 reviews an intuitive version of the formalism in the first-post-Newtonian <span class="hlt">approximation</span> that bears a strong resemblance to Maxwell's theory of electromagnetism. Chapter 3 applies this <span class="hlt">approximation</span> to relate the simultaneous bobbing motion of <span class="hlt">rotating</span> black holes in the superkick configuration---equal-mass black holes with their spins anti-aligned and in the orbital plane---to the flow of momentum in the spacetime, prior to the black holes' merger. Chapter 4 then uses the Landau-Lifshitz formalism to explain the dynamics of a head-on merger of spinning black holes, whose spins are anti-aligned and transverse to the infalling motion. Before they merge, the black holes move with a large, transverse, velocity, which we can explain using the post-Newtonian <span class="hlt">approximation</span>; as the holes merge and form a single black hole, we can use the Landau-Lifshitz formalism without any <span class="hlt">approximations</span> to connect the slowing of the final black hole to its absorbing momentum density during the merger. In Chapters 5</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22349603','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22349603"><span>Extracorporeal shock <span class="hlt">wave</span> therapy is not useful after arthroscopic <span class="hlt">rotator</span> cuff repair.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Jae Yoon; Lee, Jae Sung; Park, Chi Woo</p> <p>2012-12-01</p> <p>Extracorporeal shock <span class="hlt">wave</span> therapy (ESWT) is known to accelerate the healing of musculoskeletal tissue. The purpose of this study was to test the hypothesis that ESWT stimulates <span class="hlt">rotator</span> cuff healing after arthroscopic repair. Seventy-one consecutive patients with a small- to large-sized <span class="hlt">rotator</span> cuff tear underwent arthroscopic <span class="hlt">rotator</span> cuff repair. The patients were randomized into two groups: 35 patients underwent ESWT at 6 weeks after surgery (ESWT group) and 36 patients did not (control group). Cuff integrity was evaluated with computed tomographic arthrography at 6 months after surgery. Constant and UCLA scores were measurable outcomes. All patients were available for a minimum one-year follow-up. The mean age of the ESWT and control groups was 59.4 (SD: 7.7) and 58.6 years (SD: 7.8) (n.s.). There were no significant differences in tear size and repair method between the two groups (n.s.). The mean Constant and UCLA scores, respectively, increased from 54.6 to 90.6 (P < 0.001) and from 18.5 to 27.4 (P < 0.001) in the ESWT group, and from 58.9 to 89.3 (P < 0.001) and 18.5 to 27.4 in the control group. Computed tomographic arthrography was performed in 26 patients from the ESWT group and 24 from the control group, and cuff integrity was maintained in 46 out of 50 patients. Definite re-tear was observed in two patients of the ESWT group and four of the controls. There were no complications associated with ESWT. This study failed to prove that ESWT stimulates <span class="hlt">rotator</span> cuff healing after arthroscopic <span class="hlt">rotator</span> cuff repair. Additional ESWT after <span class="hlt">rotator</span> cuff repair could theoretically be advantageous, and it was proven to be safe in this study. II.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhDT.......104W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT.......104W"><span>Gravitational <span class="hlt">waves</span> from <span class="hlt">rotating</span> neutron stars and compact binary systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wade, Leslie E., IV</p> <p></p> <p>It is widely anticipated that the first direct detections of gravitational <span class="hlt">waves</span> will be made by advanced gravitational-<span class="hlt">wave</span> detectors, such as the two Laser Interferometer Gravitational-<span class="hlt">wave</span> Observatories (LIGO) and the Virgo interferometer. In preparation for the advanced detector era, I have worked on both detection and post-detection efforts involving two gravitational <span class="hlt">wave</span> sources: isolated <span class="hlt">rotating</span> neutron stars (NSs) and compact binary coalescences (CBCs). My dissertation includes three main research projects: 1) a population synthesis study assessing the detectability of isolated NSs, 2) a CBC search for intermediate-mass black-hole binaries (IMBHBs), and 3) new methods for directly measuring the neutron-star (NS) equation of state (EOS). Direct detections of gravitational <span class="hlt">waves</span> will enrich our current astrophysical knowledge. One such contribution will be through population synthesis of isolated NSs. My collaborators and I show that advanced gravitational-<span class="hlt">wave</span> detectors can be used to constrain the properties of the Galactic NS population. Gravitational <span class="hlt">wave</span> detections can also shine light on a currently mysterious astrophysical object: intermediate mass black holes. In developing the IMBHB search, we performed a mock data challenge where signals with total masses up to a few hundred solar masses were injected into recolored data from LIGO's sixth science run. Since this is the first time a matched filter search has been developed to search for IMBHBs, I discuss what was learned during the mock data challenge and how we plan to improve the search going forward. The final aspect of my dissertation focuses on important post-detection science. I present results for a new method of directly measuring the NS EOS. This is done by estimating the parameters of a 4-piece polytropic EOS model that matches theoretical EOS candidates to a few percent. We show that advanced detectors will be capable of measuring the NS radius to within a kilometer for stars with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950039785&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfaraday','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950039785&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfaraday"><span>The study of coronal plasma structures and fluctuations with Faraday <span class="hlt">rotation</span> measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sakurai, Takayuki; Sprangler, Steven R.</p> <p>1994-01-01</p> <p>We report dual-frequency, polarimetric measurements of Faraday <span class="hlt">rotation</span> of extragalactic radio sources viewed through the solar corona. The observations were made at the Very Large Array in 1990 during solar maximum. Of the nine observed, an excess <span class="hlt">rotation</span> measure of -12.6 rad/sq m was detected for one source (0010+005), which was observed at an elongation of about 9 solar radii. This measurement is in fair agreement with an a priori model <span class="hlt">rotation</span> measure of -8.6 rad/sq m estimated from coronal potential field models and the electron density model of Paetzold et al. (1992). Our measurement provides a value for the coronal magnetic field strength at 9 solar radii given a knowledge of the magnetic field sector structure, of 12.5 +/- 2.3 mG. <span class="hlt">Rotation</span> measurements of 0010+005 were made <span class="hlt">approximately</span> once per hour over an 11 hr period. During this interval, a slow change of about 1 rad/sq m/hr in <span class="hlt">rotation</span> measure was detected. Although we are not absolutely certain that this drift is not unremoved ionospheric Faraday <span class="hlt">rotation</span>, extensive analysis of data from the other sources suggests that this is not the case (Sakurai & Spangler 1994). The very long timescale for this variation argues against the agency of magnetohydrodynamics (MHD) <span class="hlt">waves</span>, and we suggest occultation of 0010+005 by relatively static plasma structures in the corona. We filtered our <span class="hlt">rotation</span> measure time series to search for variations on an hourly timescale, such as those reported by Hollweg et al. (1992), which could be attributed to coronal MHD <span class="hlt">waves</span>. We were unable to detect such fluctuations and can report only an upper limit to the rms variation of 1.6 rad/sq m. This upper limit is of the same order, but slightly larger than the values typically reported by Hollweg et al. (1982). This upper limit to the <span class="hlt">rotation</span> measure fluctuations limits the dimensionless <span class="hlt">wave</span> amplitude (delta B)/B in the corona to be less than 0.7. Using the number, we estimate the MHD <span class="hlt">wave</span> flux at the coronal base to be less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29092537','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29092537"><span>Fast decomposition of two ultrasound longitudinal <span class="hlt">waves</span> in cancellous bone using a phase <span class="hlt">rotation</span> parameter for bone quality assessment: Simulation study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Taki, Hirofumi; Nagatani, Yoshiki; Matsukawa, Mami; Kanai, Hiroshi; Izumi, Shin-Ichi</p> <p>2017-10-01</p> <p>Ultrasound signals that pass through cancellous bone may be considered to consist of two longitudinal <span class="hlt">waves</span>, which are called fast and slow <span class="hlt">waves</span>. Accurate decomposition of these fast and slow <span class="hlt">waves</span> is considered to be highly beneficial in determination of the characteristics of cancellous bone. In the present study, a fast decomposition method using a <span class="hlt">wave</span> transfer function with a phase <span class="hlt">rotation</span> parameter was applied to received signals that have passed through bovine bone specimens with various bone volume to total volume (BV/TV) ratios in a simulation study, where the elastic finite-difference time-domain method is used and the ultrasound <span class="hlt">wave</span> propagated parallel to the bone axes. The proposed method succeeded to decompose both fast and slow <span class="hlt">waves</span> accurately; the normalized residual intensity was less than -19.5 dB when the specimen thickness ranged from 4 to 7 mm and the BV/TV value ranged from 0.144 to 0.226. There was a strong relationship between the phase <span class="hlt">rotation</span> value and the BV/TV value. The ratio of the peak envelope amplitude of the decomposed fast <span class="hlt">wave</span> to that of the slow <span class="hlt">wave</span> increased monotonically with increasing BV/TV ratio, indicating the high performance of the proposed method in estimation of the BV/TV value in cancellous bone.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20180002977','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20180002977"><span>Examination of <span class="hlt">Wave</span> Speed in <span class="hlt">Rotating</span> Detonation Engines Using Simplified Computational Fluid Dynamics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Paxson, Daniel E.</p> <p>2018-01-01</p> <p>A simplified, two-dimensional, computational fluid dynamic (CFD) simulation, with a reactive Euler solver is used to examine possible causes for the low detonation <span class="hlt">wave</span> propagation speeds that are consistently observed in air breathing <span class="hlt">rotating</span> detonation engine (RDE) experiments. Intense, small-scale turbulence is proposed as the primary mechanism. While the solver cannot model this turbulence, it can be used to examine the most likely, and profound effect of turbulence. That is a substantial enlargement of the reaction zone, or equivalently, an effective reduction in the chemical reaction rate. It is demonstrated that in the unique flowfield of the RDE, a reduction in reaction rate leads to a reduction in the detonation speed. A subsequent test of reduced reaction rate in a purely one-dimensional pulsed detonation engine (PDE) flowfield yields no reduction in <span class="hlt">wave</span> speed. The reasons for this are explained. The impact of reduced <span class="hlt">wave</span> speed on RDE performance is then examined, and found to be minimal. Two other potential mechanisms are briefly examined. These are heat transfer, and reactive mixture non-uniformity. In the context of the simulation used for this study, both mechanisms are shown to have negligible effect on either <span class="hlt">wave</span> speed or performance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SurSc.630..301I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SurSc.630..301I"><span>High resolution electron energy loss spectroscopy of spin <span class="hlt">waves</span> in ultra-thin film - The return of the adiabatic <span class="hlt">approximation</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ibach, Harald</p> <p>2014-12-01</p> <p>The paper reports on recent considerable improvements in electron energy loss spectroscopy (EELS) of spin <span class="hlt">waves</span> in ultra-thin films. Spin <span class="hlt">wave</span> spectra with 4 meV resolution are shown. The high energy resolution enables the observation of standing modes in ultra-thin films in the <span class="hlt">wave</span> vector range of 0.15 Å- 1 < q|| < 0.3 Å- 1. In this range, Landau damping is comparatively small and standing spin <span class="hlt">wave</span> modes are well-defined Lorentzians for which the adiabatic <span class="hlt">approximation</span> is well suited, an <span class="hlt">approximation</span> which was rightly dismissed by Mills and collaborators for spin <span class="hlt">waves</span> near the Brillouin zone boundary. With the help of published exchange coupling constants, the Heisenberg model, and a simple model for the spectral response function, experimental spectra for Co-films on Cu(100) as well as for Co films capped with further copper layers are successfully simulated. It is shown that, depending on the <span class="hlt">wave</span> vector and film thickness, the most prominent contribution to the spin <span class="hlt">wave</span> spectrum may come from the first standing mode, not from the so-called surface mode. In general, the peak position of a low-resolution spin <span class="hlt">wave</span> spectrum does not correspond to a single mode. A discussion of spin <span class="hlt">waves</span> based on the "dispersion" of the peak positions in low resolution spectra is therefore subject to errors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ArRMA.197..985F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ArRMA.197..985F"><span>Error Estimates for <span class="hlt">Approximate</span> Solutions of the Riccati Equation with Real or Complex Potentials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Finster, Felix; Smoller, Joel</p> <p>2010-09-01</p> <p>A method is presented for obtaining rigorous error estimates for <span class="hlt">approximate</span> solutions of the Riccati equation, with real or complex potentials. Our main tool is to derive invariant region estimates for complex solutions of the Riccati equation. We explain the general strategy for applying these estimates and illustrate the method in typical examples, where the <span class="hlt">approximate</span> solutions are obtained by gluing together WKB and Airy solutions of corresponding one-dimensional Schrödinger equations. Our method is motivated by, and has applications to, the analysis of linear <span class="hlt">wave</span> equations in the geometry of a <span class="hlt">rotating</span> black hole.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19113347','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19113347"><span>Alpha channeling in a <span class="hlt">rotating</span> plasma.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fetterman, Abraham J; Fisch, Nathaniel J</p> <p>2008-11-14</p> <p>The <span class="hlt">wave</span>-particle alpha-channeling effect is generalized to include <span class="hlt">rotating</span> plasma. Specifically, radio frequency <span class="hlt">waves</span> can resonate with alpha particles in a mirror machine with ExB <span class="hlt">rotation</span> to diffuse the alpha particles along constrained paths in phase space. Of major interest is that the alpha-particle energy, in addition to amplifying the rf <span class="hlt">waves</span>, can directly enhance the <span class="hlt">rotation</span> energy which in turn provides additional plasma confinement in centrifugal fusion reactors. An ancillary benefit is the rapid removal of alpha particles, which increases the fusion reactivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940028527','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940028527"><span>An <span class="hlt">approximate</span> Riemann solver for magnetohydrodynamics (that works in more than one dimension)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Powell, Kenneth G.</p> <p>1994-01-01</p> <p>An <span class="hlt">approximate</span> Riemann solver is developed for the governing equations of ideal magnetohydrodynamics (MHD). The Riemann solver has an eight-<span class="hlt">wave</span> structure, where seven of the <span class="hlt">waves</span> are those used in previous work on upwind schemes for MHD, and the eighth <span class="hlt">wave</span> is related to the divergence of the magnetic field. The structure of the eighth <span class="hlt">wave</span> is not immediately obvious from the governing equations as they are usually written, but arises from a modification of the equations that is presented in this paper. The addition of the eighth <span class="hlt">wave</span> allows multidimensional MHD problems to be solved without the use of staggered grids or a projection scheme, one or the other of which was necessary in previous work on upwind schemes for MHD. A test problem made up of a shock tube with <span class="hlt">rotated</span> initial conditions is solved to show that the two-dimensional code yields answers consistent with the one-dimensional methods developed previously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29036068','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29036068"><span>Critical object recognition in millimeter-<span class="hlt">wave</span> images with robustness to <span class="hlt">rotation</span> and scale.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mohammadzade, Hoda; Ghojogh, Benyamin; Faezi, Sina; Shabany, Mahdi</p> <p>2017-06-01</p> <p>Locating critical objects is crucial in various security applications and industries. For example, in security applications, such as in airports, these objects might be hidden or covered under shields or secret sheaths. Millimeter-<span class="hlt">wave</span> images can be utilized to discover and recognize the critical objects out of the hidden cases without any health risk due to their non-ionizing features. However, millimeter-<span class="hlt">wave</span> images usually have <span class="hlt">waves</span> in and around the detected objects, making object recognition difficult. Thus, regular image processing and classification methods cannot be used for these images and additional pre-processings and classification methods should be introduced. This paper proposes a novel pre-processing method for canceling <span class="hlt">rotation</span> and scale using principal component analysis. In addition, a two-layer classification method is introduced and utilized for recognition. Moreover, a large dataset of millimeter-<span class="hlt">wave</span> images is collected and created for experiments. Experimental results show that a typical classification method such as support vector machines can recognize 45.5% of a type of critical objects at 34.2% false alarm rate (FAR), which is a drastically poor recognition. The same method within the proposed recognition framework achieves 92.9% recognition rate at 0.43% FAR, which indicates a highly significant improvement. The significant contribution of this work is to introduce a new method for analyzing millimeter-<span class="hlt">wave</span> images based on machine vision and learning approaches, which is not yet widely noted in the field of millimeter-<span class="hlt">wave</span> image analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhFl...29k1109O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhFl...29k1109O"><span>Inverse cascades and resonant triads in <span class="hlt">rotating</span> and stratified turbulence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oks, D.; Mininni, P. D.; Marino, R.; Pouquet, A.</p> <p>2017-11-01</p> <p>Kraichnan's seminal ideas on inverse cascades yielded new tools to study common phenomena in geophysical turbulent flows. In the atmosphere and the oceans, <span class="hlt">rotation</span> and stratification result in a flow that can be <span class="hlt">approximated</span> as two-dimensional at very large scales but which requires considering three-dimensional effects to fully describe turbulent transport processes and non-linear phenomena. Motions can thus be classified into two classes: fast modes consisting of inertia-gravity <span class="hlt">waves</span> and slow quasi-geostrophic modes for which the Coriolis force and horizontal pressure gradients are close to balance. In this paper, we review previous results on the strength of the inverse cascade in <span class="hlt">rotating</span> and stratified flows and then present new results on the effect of varying the strength of <span class="hlt">rotation</span> and stratification (measured by the inverse Prandtl ratio N/f, of the Coriolis frequency to the Brunt-Väisäla frequency) on the amplitude of the <span class="hlt">waves</span> and on the flow quasi-geostrophic behavior. We show that the inverse cascade is more efficient in the range of N/f for which resonant triads do not exist, 1 /2 ≤N /f ≤2 . We then use the spatio-temporal spectrum to show that in this range slow modes dominate the dynamics, while the strength of the <span class="hlt">waves</span> (and their relevance in the flow dynamics) is weaker.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920029968&hterms=containers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcontainers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920029968&hterms=containers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcontainers"><span>Gravity Probe-B Spacecraft attitude control based on the dynamics of slosh <span class="hlt">wave</span>-induced fluid stress distribution on <span class="hlt">rotating</span> dewar container of cryogenic propellant</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hung, R. J.; Lee, C. C.; Leslie, F. W.</p> <p>1991-01-01</p> <p>The dynamical behavior of fluids, in particular the effect of surface tension on partially-filled <span class="hlt">rotating</span> fluids, in a full-scale Gravity Probe-B Spacecraft propellant dewar tank imposed by various frequencies of gravity jitters have been investigated. Results show that fluid stress distribution exerted on the outer and inner walls of <span class="hlt">rotating</span> dewar are closely related to the characteristics of slosh <span class="hlt">waves</span> excited on the liquid-vapor interface in the <span class="hlt">rotating</span> dewar tank. This can provide a set of tool for the spacecraft dynamic control leading toward the control of spacecraft unbalance caused by the uneven fluid stress distribution due to slosh <span class="hlt">wave</span> excitations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.2385V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.2385V"><span><span class="hlt">Rotational</span> elasticity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vassiliev, Dmitri</p> <p>2017-04-01</p> <p>We consider an infinite three-dimensional elastic continuum whose material points experience no displacements, only <span class="hlt">rotations</span>. This framework is a special case of the Cosserat theory of elasticity. <span class="hlt">Rotations</span> of material points are described mathematically by attaching to each geometric point an orthonormal basis that gives a field of orthonormal bases called the coframe. As the dynamical variables (unknowns) of our theory, we choose the coframe and a density. We write down the general dynamic variational functional for our <span class="hlt">rotational</span> theory of elasticity, assuming our material to be physically linear but the kinematic model geometrically nonlinear. Allowing geometric nonlinearity is natural when dealing with <span class="hlt">rotations</span> because <span class="hlt">rotations</span> in dimension three are inherently nonlinear (<span class="hlt">rotations</span> about different axes do not commute) and because there is no reason to exclude from our study large <span class="hlt">rotations</span> such as full turns. The main result of the talk is an explicit construction of a class of time-dependent solutions that we call plane <span class="hlt">wave</span> solutions; these are travelling <span class="hlt">waves</span> of <span class="hlt">rotations</span>. The existence of such explicit closed-form solutions is a non-trivial fact given that our system of Euler-Lagrange equations is highly nonlinear. We also consider a special case of our <span class="hlt">rotational</span> theory of elasticity which in the stationary setting (harmonic time dependence and arbitrary dependence on spatial coordinates) turns out to be equivalent to a pair of massless Dirac equations. The talk is based on the paper [1]. [1] C.G.Boehmer, R.J.Downes and D.Vassiliev, <span class="hlt">Rotational</span> elasticity, Quarterly Journal of Mechanics and Applied Mathematics, 2011, vol. 64, p. 415-439. The paper is a heavily revised version of preprint https://arxiv.org/abs/1008.3833</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27422985','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27422985"><span>Partial IK1 blockade destabilizes spiral <span class="hlt">wave</span> <span class="hlt">rotation</span> center without inducing <span class="hlt">wave</span> breakup and facilitates termination of reentrant arrhythmias in ventricles.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kushiyama, Yasunori; Honjo, Haruo; Niwa, Ryoko; Takanari, Hiroki; Yamazaki, Masatoshi; Takemoto, Yoshio; Sakuma, Ichiro; Kodama, Itsuo; Kamiya, Kaichiro</p> <p>2016-09-01</p> <p>It has been reported that blockade of the inward rectifier K(+) current (IK1) facilitates termination of ventricular fibrillation. We hypothesized that partial IK1 blockade destabilizes spiral <span class="hlt">wave</span> (SW) re-entry, leading to its termination. Optical action potential (AP) signals were recorded from left ventricles of Langendorff-perfused rabbit hearts with endocardial cryoablation. The dynamics of SW re-entry were analyzed during ventricular tachycardia (VT), induced by cross-field stimulation. Intercellular electrical coupling in the myocardial tissue was evaluated by the space constant. In separate experiments, AP recordings were made using the microelectrode technique from right ventricular papillary muscles of rabbit hearts. Ba(2+) (10-50 μM) caused a dose-dependent prolongation of VT cycle length and facilitated termination of VT in perfused hearts. Baseline VT was maintained by a stable rotor, where an SW <span class="hlt">rotated</span> around an I-shaped functional block line (FBL). Ba(2+) at 10 μM prolonged I-shaped FBL and phase-singularity trajectory, whereas Ba(2+) at 50 μM transformed the SW <span class="hlt">rotation</span> dynamics from a stable linear pattern to unstable circular/cycloidal meandering. The SW destabilization was not accompanied by SW breakup. Under constant pacing, Ba(2+) caused a dose-dependent prolongation of APs, and Ba(2+) at 50 μM decreased conduction velocity. In papillary muscles, Ba(2+) at 50 μM depolarized the resting membrane potential. The space constant was increased by 50 μM Ba(2+) Partial IK1 blockade destabilizes SW <span class="hlt">rotation</span> dynamics through a combination of prolongation of the <span class="hlt">wave</span> length, reduction of excitability, and enhancement of electrotonic interactions, which facilitates termination of ventricular tachyarrhythmias. Copyright © 2016 the American Physiological Society.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940012862','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940012862"><span>Review of rigorous coupled-<span class="hlt">wave</span> analysis and of homogeneous effective medium <span class="hlt">approximations</span> for high spatial-frequency surface-relief gratings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Glytsis, Elias N.; Brundrett, David L.; Gaylord, Thomas K.</p> <p>1993-01-01</p> <p>A review of the rigorous coupled-<span class="hlt">wave</span> analysis as applied to the diffraction of electro-magnetic <span class="hlt">waves</span> by gratings is presented. The analysis is valid for any polarization, angle of incidence, and conical diffraction. Cascaded and/or multiplexed gratings as well as material anisotropy can be incorporated under the same formalism. Small period rectangular groove gratings can also be modeled using <span class="hlt">approximately</span> equivalent uniaxial homogeneous layers (effective media). The ordinary and extraordinary refractive indices of these layers depend on the gratings filling factor, the refractive indices of the substrate and superstrate, and the ratio of the freespace wavelength to grating period. Comparisons of the homogeneous effective medium <span class="hlt">approximations</span> with the rigorous coupled-<span class="hlt">wave</span> analysis are presented. Antireflection designs (single-layer or multilayer) using the effective medium models are presented and compared. These ultra-short period antireflection gratings can also be used to produce soft x-rays. Comparisons of the rigorous coupled-<span class="hlt">wave</span> analysis with experimental results on soft x-ray generation by gratings are also included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ASAJ..112.2423K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ASAJ..112.2423K"><span>On the role of the frozen surface <span class="hlt">approximation</span> in small <span class="hlt">wave</span>-height perturbation theory for moving surfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keiffer, Richard; Novarini, Jorge; Scharstein, Robert</p> <p>2002-11-01</p> <p>In the standard development of the small <span class="hlt">wave</span>-height <span class="hlt">approximation</span> (SWHA) perturbation theory for scattering from moving rough surfaces [e.g., E. Y. Harper and F. M. Labianca, J. Acoust. Soc. Am. 58, 349-364 (1975)] the necessity for any sort of frozen surface <span class="hlt">approximation</span> is avoided by the replacement of the rough boundary by a flat (and static) boundary. In this paper, this seemingly fortuitous byproduct of the small <span class="hlt">wave</span>-height <span class="hlt">approximation</span> is examined and found to fail to fully agree with an analysis based on the kinematics of the problem. Specifically, the first-order correction term from standard perturbation approach predicts a scattered amplitude that depends on the source frequency, whereas the kinematics of the problem point to a scattered amplitude that depends on the scattered frequency. It is shown that a perturbation approach in which an explicit frozen surface <span class="hlt">approximation</span> is made before the SWHA is invoked predicts (first-order) scattered amplitudes that are in agreement with the kinematic analysis. [Work supported by ONR/NRL (PE 61153N-32) and by grants of computer time DoD HPC Shared Resource Center at Stennis Space Center, MS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760014920&hterms=potential+kinetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dpotential%2Bkinetic%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760014920&hterms=potential+kinetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dpotential%2Bkinetic%2Benergy"><span>Rigid <span class="hlt">rotators</span>. [deriving the time-independent energy states associated with <span class="hlt">rotational</span> motions of the molecule</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1976-01-01</p> <p>The two-particle, steady-state Schroedinger equation is transformed to center of mass and internuclear distance vector coordinates, leading to the free particle <span class="hlt">wave</span> equation for the kinetic energy motion of the molecule and a decoupled <span class="hlt">wave</span> equation for a single particle of reduced mass moving in a spherical potential field. The latter describes the vibrational and <span class="hlt">rotational</span> energy modes of the diatomic molecule. For fixed internuclear distance, this becomes the equation of rigid <span class="hlt">rotator</span> motion. The classical partition function for the <span class="hlt">rotator</span> is derived and compared with the quantum expression. Molecular symmetry effects are developed from the generalized Pauli principle that the steady-state <span class="hlt">wave</span> function of any system of fundamental particles must be antisymmetric. Nuclear spin and spin quantum functions are introduced and ortho- and para-states of <span class="hlt">rotators</span>, along with their degeneracies, are defined. Effects of nuclear spin on entropy are deduced. Next, rigid polyatomic <span class="hlt">rotators</span> are considered and the partition function for this case is derived. The patterns of <span class="hlt">rotational</span> energy levels for nonlinear molecules are discussed for the spherical symmetric top, for the prolate symmetric top, for the oblate symmetric top, and for the asymmetric top. Finally, the equilibrium energy and specific heat of rigid <span class="hlt">rotators</span> are derived.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830024245','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830024245"><span>System for controlled acoustic <span class="hlt">rotation</span> of objects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barmatz, M. B. (Inventor)</p> <p>1983-01-01</p> <p>A system is described for use with acoustically levitated objects, which enables close control of <span class="hlt">rotation</span> of the object. One system includes transducers that propagate acoustic <span class="hlt">waves</span> along the three dimensions (X, Y, Z) of a chamber of rectangular cross section. Each transducers generates one <span class="hlt">wave</span> which is resonant to a corresponding chamber dimension to acoustically levitate an object, and additional higher frequency resonant wavelengths for controlling <span class="hlt">rotation</span> of the object. The three chamber dimensions and the corresponding three levitation modes (resonant wavelengths) are all different, to avoid degeneracy, or interference, of <span class="hlt">waves</span> with one another, that could have an effect on object <span class="hlt">rotation</span>. Only the higher frequencies, with pairs of them having the same wavelength, are utilized to control <span class="hlt">rotation</span>, so that <span class="hlt">rotation</span> is controlled independently of levitation and about any arbitrarily chosen axis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22436580-effects-reagent-rotational-excitation-chd-sub-sub-cd-sub-reaction-seven-dimensional-time-dependent-wave-packet-study','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22436580-effects-reagent-rotational-excitation-chd-sub-sub-cd-sub-reaction-seven-dimensional-time-dependent-wave-packet-study"><span>Effects of reagent <span class="hlt">rotational</span> excitation on the H + CHD{sub 3} → H{sub 2} + CD{sub 3} reaction: A seven dimensional time-dependent <span class="hlt">wave</span> packet study</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zhang, Zhaojun; Zhang, Dong H., E-mail: zhangdh@dicp.ac.cn</p> <p></p> <p>Seven-dimensional time-dependent <span class="hlt">wave</span> packet calculations have been carried out for the title reaction to obtain reaction probabilities and cross sections for CHD{sub 3} in J{sub 0} = 1, 2 <span class="hlt">rotationally</span> excited initial states with k{sub 0} = 0 − J{sub 0} (the projection of CHD{sub 3} <span class="hlt">rotational</span> angular momentum on its C{sub 3} axis). Under the centrifugal sudden (CS) <span class="hlt">approximation</span>, the initial states with the projection of the total angular momentum on the body fixed axis (K{sub 0}) equal to k{sub 0} are found to be much more reactive, indicating strong dependence of reactivity on the orientation of the reagentmore » CHD{sub 3} with respect to the relative velocity between the reagents H and CHD{sub 3}. However, at the coupled-channel (CC) level this dependence becomes much weak although in general the K{sub 0} specified cross sections for the K{sub 0} = k{sub 0} initial states remain primary to the overall cross sections, implying the Coriolis coupling is important to the dynamics of the reaction. The calculated CS and CC integral cross sections obtained after K{sub 0} averaging for the J{sub 0} = 1, 2 initial states with all different k{sub 0} are essentially identical to the corresponding CS and CC results for the J{sub 0} = 0 initial state, meaning that the initial <span class="hlt">rotational</span> excitation of CHD{sub 3} up to J{sub 0} = 2, regardless of its initial k{sub 0}, does not have any effect on the total cross sections for the title reaction, and the errors introduced by the CS <span class="hlt">approximation</span> on integral cross sections for the <span class="hlt">rotationally</span> excited J{sub 0} = 1, 2 initial states are the same as those for the J{sub 0} = 0 initial state.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007IJNAM..31...53J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007IJNAM..31...53J"><span>A new <span class="hlt">approximation</span> for pore pressure accumulation in marine sediment due to water <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jeng, D.-S.; Seymour, B. R.; Li, J.</p> <p>2007-01-01</p> <p>The residual mechanism of <span class="hlt">wave</span>-induced pore water pressure accumulation in marine sediments is re-examined. An analytical <span class="hlt">approximation</span> is derived using a linear relation for pore pressure generation in cyclic loading, and mistakes in previous solutions (Int. J. Numer. Anal. Methods Geomech. 2001; 25:885-907; J. Offshore Mech. Arctic Eng. (ASME) 1989; 111(1):1-11) are corrected. A numerical scheme is then employed to solve the case with a non-linear relation for pore pressure generation. Both analytical and numerical solutions are verified with experimental data (Laboratory and field investigation of <span class="hlt">wave</span>-sediment interaction. Joseph H. Defrees Hydraulics Laboratory, School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, 1983), and provide a better prediction of pore pressure accumulation than the previous solution (J. Offshore Mech. Arctic Eng. (ASME) 1989; 111(1):1-11). The parametric study concludes that the pore pressure accumulation and use of full non-linear relation of pore pressure become more important under the following conditions: (1) large <span class="hlt">wave</span> amplitude, (2) longer <span class="hlt">wave</span> period, (3) shallow water, (4) shallow soil and (5) softer soils with a low consolidation coefficient. Copyright</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatAs.tmp...54L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatAs.tmp...54L"><span>Global-scale equatorial Rossby <span class="hlt">waves</span> as an essential component of solar internal dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Löptien, Björn; Gizon, Laurent; Birch, Aaron C.; Schou, Jesper; Proxauf, Bastian; Duvall, Thomas L.; Bogart, Richard S.; Christensen, Ulrich R.</p> <p>2018-05-01</p> <p>The Sun’s complex dynamics is controlled by buoyancy and <span class="hlt">rotation</span> in the convection zone. Large-scale flows are dominated by vortical motions1 and appear to be weaker than expected in the solar interior2. One possibility is that <span class="hlt">waves</span> of vorticity due to the Coriolis force, known as Rossby <span class="hlt">waves</span>3 or r modes4, remove energy from convection at the largest scales5. However, the presence of these <span class="hlt">waves</span> in the Sun is still debated. Here, we unambiguously discover and characterize retrograde-propagating vorticity <span class="hlt">waves</span> in the shallow subsurface layers of the Sun at azimuthal wavenumbers below 15, with the dispersion relation of textbook sectoral Rossby <span class="hlt">waves</span>. The <span class="hlt">waves</span> have lifetimes of several months, well-defined mode frequencies below twice the solar <span class="hlt">rotational</span> frequency, and eigenfunctions of vorticity that peak at the equator. Rossby <span class="hlt">waves</span> have nearly as much vorticity as the convection at the same scales, thus they are an essential component of solar dynamics. We observe a transition from turbulence-like to <span class="hlt">wave</span>-like dynamics around the Rhines scale6 of angular wavenumber of <span class="hlt">approximately</span> 20. This transition might provide an explanation for the puzzling deficit of kinetic energy at the largest spatial scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1440782-wave-kinetics-drift-wave-turbulence-zonal-flows-beyond-ray-approximation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1440782-wave-kinetics-drift-wave-turbulence-zonal-flows-beyond-ray-approximation"><span><span class="hlt">Wave</span> kinetics of drift-<span class="hlt">wave</span> turbulence and zonal flows beyond the ray <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zhu, Hongxuan; Zhou, Yao; Ruiz, D. E.</p> <p></p> <p>Inhomogeneous drift-<span class="hlt">wave</span> turbulence can be modeled as an effective plasma where drift <span class="hlt">waves</span> act as quantumlike particles and the zonal-flow velocity serves as a collective field through which they interact. This effective plasma can be described by a Wigner-Moyal equation (WME), which generalizes the quasilinear <span class="hlt">wave</span>-kinetic equation (WKE) to the full-<span class="hlt">wave</span> regime, i.e., resolves the wavelength scale. Unlike <span class="hlt">waves</span> governed by manifestly quantumlike equations, whose WMEs can be borrowed from quantum mechanics and are commonly known, drift <span class="hlt">waves</span> have Hamiltonians very different from those of conventional quantum particles. This causes unusual phase-space dynamics that is typically not captured by themore » WKE. We demonstrate how to correctly model this dynamics with the WME instead. Specifically, we report full-<span class="hlt">wave</span> phase-space simulations of the zonal-flow formation (zonostrophic instability), deterioration (tertiary instability), and the so-called predator-prey oscillations. We also show how the WME facilitates analysis of these phenomena, namely, (i) we show that full-<span class="hlt">wave</span> effects critically affect the zonostrophic instability, particularly its nonlinear stage and saturation; (ii) we derive the tertiary-instability growth rate; and (iii) we demonstrate that, with full-<span class="hlt">wave</span> effects retained, the predator-prey oscillations do not require zonal-flow collisional damping, contrary to previous studies. In conclusion, we also show how the famous Rayleigh-Kuo criterion, which has been missing in <span class="hlt">wave</span>-kinetic theories of drift-<span class="hlt">wave</span> turbulence, emerges from the WME.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvE..97e3210Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvE..97e3210Z"><span><span class="hlt">Wave</span> kinetics of drift-<span class="hlt">wave</span> turbulence and zonal flows beyond the ray <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, Hongxuan; Zhou, Yao; Ruiz, D. E.; Dodin, I. Y.</p> <p>2018-05-01</p> <p>Inhomogeneous drift-<span class="hlt">wave</span> turbulence can be modeled as an effective plasma where drift <span class="hlt">waves</span> act as quantumlike particles and the zonal-flow velocity serves as a collective field through which they interact. This effective plasma can be described by a Wigner-Moyal equation (WME), which generalizes the quasilinear <span class="hlt">wave</span>-kinetic equation (WKE) to the full-<span class="hlt">wave</span> regime, i.e., resolves the wavelength scale. Unlike <span class="hlt">waves</span> governed by manifestly quantumlike equations, whose WMEs can be borrowed from quantum mechanics and are commonly known, drift <span class="hlt">waves</span> have Hamiltonians very different from those of conventional quantum particles. This causes unusual phase-space dynamics that is typically not captured by the WKE. We demonstrate how to correctly model this dynamics with the WME instead. Specifically, we report full-<span class="hlt">wave</span> phase-space simulations of the zonal-flow formation (zonostrophic instability), deterioration (tertiary instability), and the so-called predator-prey oscillations. We also show how the WME facilitates analysis of these phenomena, namely, (i) we show that full-<span class="hlt">wave</span> effects critically affect the zonostrophic instability, particularly its nonlinear stage and saturation; (ii) we derive the tertiary-instability growth rate; and (iii) we demonstrate that, with full-<span class="hlt">wave</span> effects retained, the predator-prey oscillations do not require zonal-flow collisional damping, contrary to previous studies. We also show how the famous Rayleigh-Kuo criterion, which has been missing in <span class="hlt">wave</span>-kinetic theories of drift-<span class="hlt">wave</span> turbulence, emerges from the WME.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1440782-wave-kinetics-drift-wave-turbulence-zonal-flows-beyond-ray-approximation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1440782-wave-kinetics-drift-wave-turbulence-zonal-flows-beyond-ray-approximation"><span><span class="hlt">Wave</span> kinetics of drift-<span class="hlt">wave</span> turbulence and zonal flows beyond the ray <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Zhu, Hongxuan; Zhou, Yao; Ruiz, D. E.; ...</p> <p>2018-05-29</p> <p>Inhomogeneous drift-<span class="hlt">wave</span> turbulence can be modeled as an effective plasma where drift <span class="hlt">waves</span> act as quantumlike particles and the zonal-flow velocity serves as a collective field through which they interact. This effective plasma can be described by a Wigner-Moyal equation (WME), which generalizes the quasilinear <span class="hlt">wave</span>-kinetic equation (WKE) to the full-<span class="hlt">wave</span> regime, i.e., resolves the wavelength scale. Unlike <span class="hlt">waves</span> governed by manifestly quantumlike equations, whose WMEs can be borrowed from quantum mechanics and are commonly known, drift <span class="hlt">waves</span> have Hamiltonians very different from those of conventional quantum particles. This causes unusual phase-space dynamics that is typically not captured by themore » WKE. We demonstrate how to correctly model this dynamics with the WME instead. Specifically, we report full-<span class="hlt">wave</span> phase-space simulations of the zonal-flow formation (zonostrophic instability), deterioration (tertiary instability), and the so-called predator-prey oscillations. We also show how the WME facilitates analysis of these phenomena, namely, (i) we show that full-<span class="hlt">wave</span> effects critically affect the zonostrophic instability, particularly its nonlinear stage and saturation; (ii) we derive the tertiary-instability growth rate; and (iii) we demonstrate that, with full-<span class="hlt">wave</span> effects retained, the predator-prey oscillations do not require zonal-flow collisional damping, contrary to previous studies. In conclusion, we also show how the famous Rayleigh-Kuo criterion, which has been missing in <span class="hlt">wave</span>-kinetic theories of drift-<span class="hlt">wave</span> turbulence, emerges from the WME.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22340197-analytical-solution-waves-planets-atmospheric-superrotation-ii-lamb-surface-centrifugal-waves','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22340197-analytical-solution-waves-planets-atmospheric-superrotation-ii-lamb-surface-centrifugal-waves"><span>ANALYTICAL SOLUTION FOR <span class="hlt">WAVES</span> IN PLANETS WITH ATMOSPHERIC SUPERROTATION. II. LAMB, SURFACE, AND CENTRIFUGAL <span class="hlt">WAVES</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Peralta, J.; López-Valverde, M. A.; Imamura, T.</p> <p>2014-07-01</p> <p>This paper is the second in a two-part study devoted to developing tools for a systematic classification of the wide variety of atmospheric <span class="hlt">waves</span> expected on slowly <span class="hlt">rotating</span> planets with atmospheric superrotation. Starting with the primitive equations for a cyclostrophic regime, we have deduced the analytical solution for the possible <span class="hlt">waves</span>, simultaneously including the effect of the metric terms for the centrifugal force and the meridional shear of the background wind. In those cases where the conditions for the method of the multiple scales in height are met, these <span class="hlt">wave</span> solutions are also valid when vertical shear of the backgroundmore » wind is present. A total of six types of <span class="hlt">waves</span> have been found and their properties were characterized in terms of the corresponding dispersion relations and <span class="hlt">wave</span> structures. In this second part, we study the <span class="hlt">waves</span>' solutions when several atmospheric <span class="hlt">approximations</span> are applied: Lamb, surface, and centrifugal <span class="hlt">waves</span>. Lamb and surface <span class="hlt">waves</span> are found to be quite similar to those in a geostrophic regime. By contrast, centrifugal <span class="hlt">waves</span> turn out to be a special case of Rossby <span class="hlt">waves</span> that arise in atmospheres in cyclostrophic balance. Finally, we use our results to identify the nature of the <span class="hlt">waves</span> behind atmospheric periodicities found in polar and lower latitudes of Venus's atmosphere.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22583215','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22583215"><span>The role of axis embedding on rigid rotor decomposition analysis of variational rovibrational <span class="hlt">wave</span> functions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Szidarovszky, Tamás; Fábri, Csaba; Császár, Attila G</p> <p>2012-05-07</p> <p><span class="hlt">Approximate</span> <span class="hlt">rotational</span> characterization of variational rovibrational <span class="hlt">wave</span> functions via the rigid rotor decomposition (RRD) protocol is developed for Hamiltonians based on arbitrary sets of internal coordinates and axis embeddings. An efficient and general procedure is given that allows employing the Eckart embedding with arbitrary polyatomic Hamiltonians through a fully numerical approach. RRD tables formed by projecting <span class="hlt">rotational</span>-vibrational <span class="hlt">wave</span> functions into products of rigid-rotor basis functions and previously determined vibrational eigenstates yield rigid-rotor labels for rovibrational eigenstates by selecting the largest overlap. Embedding-dependent RRD analyses are performed, up to high energies and <span class="hlt">rotational</span> excitations, for the H(2) (16)O isotopologue of the water molecule. Irrespective of the embedding chosen, the RRD procedure proves effective in providing unambiguous <span class="hlt">rotational</span> assignments at low energies and J values. <span class="hlt">Rotational</span> labeling of rovibrational states of H(2) (16)O proves to be increasingly difficult beyond about 10,000 cm(-1), close to the barrier to linearity of the water molecule. For medium energies and excitations the Eckart embedding yields the largest RRD coefficients, thus providing the largest number of unambiguous <span class="hlt">rotational</span> labels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22661284-evolution-binary-supermassive-black-holes-rotating-nuclei','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22661284-evolution-binary-supermassive-black-holes-rotating-nuclei"><span>Evolution of Binary Supermassive Black Holes in <span class="hlt">Rotating</span> Nuclei</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Rasskazov, Alexander; Merritt, David</p> <p></p> <p>The interaction of a binary supermassive black hole with stars in a galactic nucleus can result in changes to all the elements of the binary’s orbit, including the angles that define its orientation. If the nucleus is <span class="hlt">rotating</span>, the orientation changes can be large, causing large changes in the binary’s orbital eccentricity as well. We present a general treatment of this problem based on the Fokker–Planck equation for f , defined as the probability distribution for the binary’s orbital elements. First- and second-order diffusion coefficients are derived for the orbital elements of the binary using numerical scattering experiments, and analyticmore » <span class="hlt">approximations</span> are presented for some of these coefficients. Solutions of the Fokker–Planck equation are then derived under various assumptions about the initial <span class="hlt">rotational</span> state of the nucleus and the binary hardening rate. We find that the evolution of the orbital elements can become qualitatively different when we introduce nuclear <span class="hlt">rotation</span>: (1) the orientation of the binary’s orbit evolves toward alignment with the plane of <span class="hlt">rotation</span> of the nucleus and (2) binary orbital eccentricity decreases for aligned binaries and increases for counteraligned ones. We find that the diffusive (random-walk) component of a binary’s evolution is small in nuclei with non-negligible <span class="hlt">rotation</span>, and we derive the time-evolution equations for the semimajor axis, eccentricity, and inclination in that <span class="hlt">approximation</span>. The aforementioned effects could influence gravitational <span class="hlt">wave</span> production as well as the relative orientation of host galaxies and radio jets.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830052223&hterms=FitzGerald&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DFitzGerald','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830052223&hterms=FitzGerald&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DFitzGerald"><span>High-resolution submillimeter-<span class="hlt">wave</span> radiometry of supersonic flow</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dionne, G. F.; Weiss, J. A.; Fitzgerald, J. F.; Fetterman, H. R.; Litvak, M. M.</p> <p>1983-01-01</p> <p>The recent development of a high-resolution submillimeter-<span class="hlt">wave</span> heterodyne radiometer has made possible the first measurements of H2O molecule <span class="hlt">rotational</span> line excitation temperatures and detailed profiles in supersonic flow. Absorption signals were measured across the flow for the 2/11/ from 2//02/ (752 GHz) para-H2O <span class="hlt">rotational</span> transition against a hot background. These signals decrease downstream owing to the volume expansion of the gas away from the sonic nozle exit in the high-vacuum chamber. Radiative transfer calculations based on the large-velocity-gradient <span class="hlt">approximation</span> and multilevel statistical equilibrium agree with these results and with the measured spectral line shapes. The data reveal nearly isentropic gas expansion and cooling. These studies have shown that submillimeter-<span class="hlt">wave</span> heterodyne radiometry can be useful for remote sensing of supersonic flow with low mass flux, provided the signal transmission is through a dry or thin atmosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890036090&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Brotor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890036090&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dwave%2Brotor"><span>Body frame close coupling <span class="hlt">wave</span> packet approach to gas phase atom-rigid rotor inelastic collisions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sun, Y.; Judson, R. S.; Kouri, D. J.</p> <p>1989-01-01</p> <p>The close coupling <span class="hlt">wave</span> packet (CCWP) method is formulated in a body-fixed representation for atom-rigid rotor inelastic scattering. For J greater than j-max (where J is the total angular momentum and j is the <span class="hlt">rotational</span> quantum number), the computational cost of propagating the coupled channel <span class="hlt">wave</span> packets in the body frame is shown to scale <span class="hlt">approximately</span> as N exp 3/2, where N is the total number of channels. For large numbers of channels, this will be much more efficient than the space frame CCWP method previously developed which scales <span class="hlt">approximately</span> as N-squared under the same conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5541368-vibrational-rotational-deexcitation-hf-collision-he','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5541368-vibrational-rotational-deexcitation-hf-collision-he"><span>Vibrational-<span class="hlt">rotational</span> deexcitation of HF in collision with He</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Bieniek, R.J.</p> <p></p> <p>State-to-state cross sections are reported for vibrational-<span class="hlt">rotational</span> transitions for HF in collisions with He, at collisional energies of 0.5 and 1.0 eV. These were computed within the infinite-order sudden (IOS) <span class="hlt">approximation</span> using adiabatic, distorted-<span class="hlt">wave</span> techniques. Values are tabulated for the vibrational-<span class="hlt">rotational</span> deexcitation sequences (v, j) ..-->.. (v--1, 0), with v = 1, 2, 3, 4 and j = 0 -- 40. These quenching cross sections can be used in conjunction with IOS factorization formulas to compute VRT cross sections for final <span class="hlt">rotational</span> states other than j/sub f/ = 0. In addition to IOS results, vibrational quenching cross sections were computedmore » using the much more simple breathing-sphere technique. The breathing-sphere results compare favorably to the more accurate IOS results, particularly as to energy dependence. This suggests a simple method of utilizing known quenching cross sections to predict values for different vibrational levels and/or collisional energies.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JPhCS.147a2081O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JPhCS.147a2081O"><span>Nonlinear CARS measurement of nitrogen vibrational and <span class="hlt">rotational</span> temperatures behind hypervelocity strong shock <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Osada, Takashi; Endo, Youichi; Kanazawa, Chikara; Ota, Masanori; Maeno, Kazuo</p> <p>2009-02-01</p> <p>The hypervelocity strong shock <span class="hlt">waves</span> are generated, when the space vehicles reenter the atmosphere from space. Behind the shock <span class="hlt">wave</span> radiative and non-equilibrium flow is generated in front of the surface of the space vehicle. Many studies have been reported to investigate the phenomena for the aerospace exploit and reentry. The research information and data on the high temperature flows have been available to the rational heatproof design of the space vehicles. Recent development of measurement techniques with laser systems and photo-electronics now enables us to investigate the hypervelocity phenomena with greatly advanced accuracy. In this research strong shock <span class="hlt">waves</span> are generated in low-density gas to simulate the reentry range gas flow with a free-piston double-diaphragm shock tube, and CARS (Coherent Anti-stokes Raman Spectroscopy) measurement method is applied to the hypervelocity flows behind the shock <span class="hlt">waves</span>, where spectral signals of high space/time resolution are acquired. The CARS system consists of YAG and dye lasers, a spectroscope, and a CCD camera system. We obtain the CARS signal spectrum data by this special time-resolving experiment, and the vibrational and <span class="hlt">rotational</span> temperatures of N2 are determined by fitting between the experimental spectroscopic profile data and theoretically estimated spectroscopic data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...853..144D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...853..144D"><span>Role of Interaction between Magnetic Rossby <span class="hlt">Waves</span> and Tachocline Differential <span class="hlt">Rotation</span> in Producing Solar Seasons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dikpati, Mausumi; McIntosh, Scott W.; Bothun, Gregory; Cally, Paul S.; Ghosh, Siddhartha S.; Gilman, Peter A.; Umurhan, Orkan M.</p> <p>2018-02-01</p> <p>We present a nonlinear magnetohydrodynamic shallow-water model for the solar tachocline (MHD-SWT) that generates quasi-periodic tachocline nonlinear oscillations (TNOs) that can be identified with the recently discovered solar “seasons.” We discuss the properties of the hydrodynamic and magnetohydrodynamic Rossby <span class="hlt">waves</span> that interact with the differential <span class="hlt">rotation</span> and toroidal fields to sustain these oscillations, which occur due to back-and-forth energy exchanges among potential, kinetic, and magnetic energies. We perform model simulations for a few years, for selected example cases, in both hydrodynamic and magnetohydrodynamic regimes and show that the TNOs are robust features of the MHD-SWT model, occurring with periods of 2–20 months. We find that in certain cases multiple unstable shallow-water modes govern the dynamics, and TNO periods vary with time. In hydrodynamically governed TNOs, the energy exchange mechanism is simple, occurring between the Rossby <span class="hlt">waves</span> and differential <span class="hlt">rotation</span>. But in MHD cases, energy exchange becomes much more complex, involving energy flow among six energy reservoirs by means of eight different energy conversion processes. For toroidal magnetic bands of 5 and 35 kG peak amplitudes, both placed at 45° latitude and oppositely directed in north and south hemispheres, we show that the energy transfers responsible for TNO, as well as westward phase propagation, are evident in synoptic maps of the flow, magnetic field, and tachocline top-surface deformations. Nonlinear mode–mode interaction is particularly dramatic in the strong-field case. We also find that the TNO period increases with a decrease in <span class="hlt">rotation</span> rate, implying that the younger Sun had more frequent seasons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006CosRe..44...39R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006CosRe..44...39R"><span>Dynamics of a plasma ring <span class="hlt">rotating</span> in the magnetic field of a central body: Magneto-gravitational <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rabinovich, B. I.</p> <p>2006-01-01</p> <p>The model problem of the dynamics of a planar plasma ring <span class="hlt">rotating</span> in the dipole magnetic field of a central body is considered. A finite-dimensional mathematical model of the system is synthesized by the Boubnov-Galerkin method. The class of solutions corresponding to magneto-gravitational <span class="hlt">waves</span> associated with deformations of the ring boundaries is investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvA..96f3401P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvA..96f3401P"><span>Strong-field <span class="hlt">approximation</span> in a <span class="hlt">rotating</span> frame: High-order harmonic emission from p states in bicircular fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pisanty, Emilio; Jiménez-Galán, Álvaro</p> <p>2017-12-01</p> <p>High-order harmonic generation with bicircular fields—the combination of counter-<span class="hlt">rotating</span> circularly polarized pulses at different frequencies—results in a series of short-wavelength XUV harmonics with alternating circular polarizations, and experiments show that there is an asymmetry in the emission between the two helicities: a slight one in helium and a larger one in neon and argon, where the emission is carried out by p -shell electrons. Here we analyze this asymmetry by switching to a <span class="hlt">rotating</span> frame in which the field is linearly polarized; this induces an effective magnetic field which lowers the ionization potential of the p + orbital that corotates with the lower-frequency driver, enhancing its harmonic emission and the overall helicity of the generated harmonics, while also introducing nontrivial effects from the transformation to a noninertial frame in complex time. In addition, this analysis directly relates the small asymmetry produced by s -shell emission to the imaginary part of the recollision velocity in the standard strong-field-<span class="hlt">approximation</span> formalism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22356691-triggering-collapse-presolar-dense-cloud-core-injecting-short-lived-radioisotopes-shock-wave-iii-rotating-three-dimensional-cloud-cores','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22356691-triggering-collapse-presolar-dense-cloud-core-injecting-short-lived-radioisotopes-shock-wave-iii-rotating-three-dimensional-cloud-cores"><span>Triggering collapse of the presolar dense cloud core and injecting short-lived radioisotopes with a shock <span class="hlt">wave</span>. III. <span class="hlt">Rotating</span> three-dimensional cloud cores</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Boss, Alan P.; Keiser, Sandra A., E-mail: boss@dtm.ciw.edu</p> <p>2014-06-10</p> <p>A key test of the supernova triggering and injection hypothesis for the origin of the solar system's short-lived radioisotopes is to reproduce the inferred initial abundances of these isotopes. We present here the most detailed models to date of the shock <span class="hlt">wave</span> triggering and injection process, where shock <span class="hlt">waves</span> with varied properties strike fully three-dimensional, <span class="hlt">rotating</span>, dense cloud cores. The models are calculated with the FLASH adaptive mesh hydrodynamics code. Three different outcomes can result: triggered collapse leading to fragmentation into a multiple protostar system; triggered collapse leading to a single protostar embedded in a protostellar disk; or failure tomore » undergo dynamic collapse. Shock <span class="hlt">wave</span> material is injected into the collapsing clouds through Rayleigh-Taylor fingers, resulting in initially inhomogeneous distributions in the protostars and protostellar disks. Cloud <span class="hlt">rotation</span> about an axis aligned with the shock propagation direction does not increase the injection efficiency appreciably, as the shock parameters were chosen to be optimal for injection even in the absence of <span class="hlt">rotation</span>. For a shock <span class="hlt">wave</span> from a core-collapse supernova, the dilution factors for supernova material are in the range of ∼10{sup –4} to ∼3 × 10{sup –4}, in agreement with recent laboratory estimates of the required amount of dilution for {sup 60}Fe and {sup 26}Al. We conclude that a type II supernova remains as a promising candidate for synthesizing the solar system's short-lived radioisotopes shortly before their injection into the presolar cloud core by the supernova's remnant shock <span class="hlt">wave</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MicST..30..129W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MicST..30..129W"><span>Numerical Study of Nonlinear Structures of Locally Excited Marangoni Convection in the Long-<span class="hlt">Wave</span> <span class="hlt">Approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wertgeim, Igor I.</p> <p>2018-02-01</p> <p>We investigate stationary and non-stationary solutions of nonlinear equations of the long-<span class="hlt">wave</span> <span class="hlt">approximation</span> for the Marangoni convection caused by a localized source of heat or a surface active impurity (surfactant) in a thin horizontal layer of a viscous incompressible fluid with a free surface. The distribution of heat or concentration flux is determined by the uniform vertical gradient of temperature or impurity concentration, distorted by the imposition of a slightly inhomogeneous heating or of surfactant, localized in the horizontal plane. The lower boundary of the layer is considered thermally insulated or impermeable, whereas the upper boundary is free and deformable. The equations obtained in the long-<span class="hlt">wave</span> <span class="hlt">approximation</span> are formulated in terms of the amplitudes of the temperature distribution or impurity concentration, deformation of the surface, and vorticity. For a simplification of the problem, a sequence of nonlinear equations is obtained, which in the simplest form leads to a nonlinear Schrödinger equation with a localized potential. The basic state of the system, its dependence on the parameters and stability are investigated. For stationary solutions localized in the region of the surface tension inhomogeneity, domains of parameters corresponding to different spatial patterns are delineated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..DFDH35007K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..DFDH35007K"><span>Chemical Kinetics in the expansion flow field of a <span class="hlt">rotating</span> detonation-<span class="hlt">wave</span> engine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kailasanath, Kazhikathra; Schwer, Douglas</p> <p>2014-11-01</p> <p><span class="hlt">Rotating</span> detonation-<span class="hlt">wave</span> engines (RDE) are a form of continuous detonation-<span class="hlt">wave</span> engines. They potentially provide further gains in performance than an intermittent or pulsed detonation-<span class="hlt">wave</span> engine (PDE). The overall flow field in an idealized RDE, primarily consisting of two concentric cylinders, has been discussed in previous meetings. Because of the high pressures involved and the lack of adequate reaction mechanisms for this regime, previous simulations have typically used simplified chemistry models. However, understanding the exhaust species concentrations in propulsion devices is important for both performance considerations as well as estimating pollutant emissions. A key step towards addressing this need will be discussed in this talk. In this approach, an induction parameter model is used for simulating the detonation but a more detailed finite-chemistry model is used in the expansion flow region, where the pressures are lower and the uncertainties in the chemistry model are greatly reduced. Results show that overall radical concentrations in the exhaust flow are substantially lower than from earlier predictions with simplified models. The performance of a baseline hydrogen/air RDE increased from 4940 s to 5000 s with the expansion flow chemistry, due to recombination of radicals and more production of H2O, resulting in additional heat release.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvL.120h3205L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvL.120h3205L"><span>Near-Resonant Raman Amplification in the <span class="hlt">Rotational</span> Quantum <span class="hlt">Wave</span> Packets of Nitrogen Molecular Ions Generated by Strong Field Ionization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Zhaoxiang; Yao, Jinping; Chen, Jinming; Xu, Bo; Chu, Wei; Cheng, Ya</p> <p>2018-02-01</p> <p>The generation of laserlike narrow bandwidth emissions from nitrogen molecular ions (N2+ ) generated in intense near- and mid infrared femtosecond laser fields has aroused much interest because of the mysterious physics underlying such a phenomenon. Here, we perform a pump-probe measurement on the nonlinear interaction of <span class="hlt">rotational</span> quantum <span class="hlt">wave</span> packets of N2+ generated in midinfrared (e.g., at a wavelength centered at 1580 nm) femtosecond laser fields with an ultrashort probe pulse whose broad spectrum overlaps both P - and R -branch <span class="hlt">rotational</span> transition lines between the electronic states N2+(B2Σu+,v'=0 ) and N2+(X2Σg+,v =0 ) . The results indicate the occurrence of highly efficient near-resonant stimulated Raman scattering in the quantum <span class="hlt">wave</span> packets of N2+ ions generated in strong laser fields in the midinfrared region, of which the underlying mechanism is different from that of the air lasers generated in atmospheric environment when pumping with 800 nm intense pulses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.2286B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.2286B"><span>Nearshore sandbar <span class="hlt">rotation</span> at single-barred embayed beaches</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blossier, B.; Bryan, K. R.; Daly, C. J.; Winter, C.</p> <p>2016-04-01</p> <p>The location of a shore-parallel nearshore sandbar derived from 7 years of video imagery data at the single-barred embayed Tairua Beach (NZ) is investigated to assess the contribution of barline <span class="hlt">rotation</span> to the overall morphodynamics of sandbars in embayed environments and to characterize the process of <span class="hlt">rotation</span> in relation to external conditions. <span class="hlt">Rotation</span> induces cross-shore barline variations at the embayment extremities on the order of magnitude of those induced by alongshore uniform cross-shore migration of the bar. Two semiempirical models have been developed to relate the barline cross-shore migration and <span class="hlt">rotation</span> to external <span class="hlt">wave</span> forcing conditions. The <span class="hlt">rotation</span> model is directly derived from the cross-shore migration model. Therefore, its formulation advocates for a primary role of cross-shore processes in the <span class="hlt">rotation</span> of sandbars at embayed beaches. The orientation evolves toward an equilibrium angle directly related to the alongshore <span class="hlt">wave</span> energy gradient due to two different mechanisms. Either the bar extremities migrate in opposite directions with no overall cross-shore bar migration (pivotal <span class="hlt">rotation</span>) or the <span class="hlt">rotation</span> relates to an overall migration of the barline which is not uniform along the beach (migration-driven <span class="hlt">rotation</span>). Migration and <span class="hlt">rotation</span> characteristic response times are similar, ranging from 10 to 30 days for mild and energetic <span class="hlt">wave</span> conditions and above 200 days during very calm conditions or when the bar is located far offshore.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22311304-general-rotating-quantum-vortex-filaments-low-temperature-svistunov-model-local-induction-approximation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22311304-general-rotating-quantum-vortex-filaments-low-temperature-svistunov-model-local-induction-approximation"><span>General <span class="hlt">rotating</span> quantum vortex filaments in the low-temperature Svistunov model of the local induction <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Van Gorder, Robert A., E-mail: rav@knights.ucf.edu</p> <p>2014-06-15</p> <p>In his study of superfluid turbulence in the low-temperature limit, Svistunov [“Superfluid turbulence in the low-temperature limit,” Phys. Rev. B 52, 3647 (1995)] derived a Hamiltonian equation for the self-induced motion of a vortex filament. Under the local induction <span class="hlt">approximation</span> (LIA), the Svistunov formulation is equivalent to a nonlinear dispersive partial differential equation. In this paper, we consider a family of <span class="hlt">rotating</span> vortex filament solutions for the LIA reduction of the Svistunov formulation, which we refer to as the 2D LIA (since it permits a potential formulation in terms of two of the three Cartesian coordinates). This class of solutionsmore » holds the well-known Hasimoto-type planar vortex filament [H. Hasimoto, “Motion of a vortex filament and its relation to elastica,” J. Phys. Soc. Jpn. 31, 293 (1971)] as one reduction and helical solutions as another. More generally, we obtain solutions which are periodic in the space variable. A systematic analytical study of the behavior of such solutions is carried out. In the case where vortex filaments have small deviations from the axis of <span class="hlt">rotation</span>, closed analytical forms of the filament solutions are given. A variety of numerical simulations are provided to demonstrate the wide range of <span class="hlt">rotating</span> filament behaviors possible. Doing so, we are able to determine a number of vortex filament structures not previously studied. We find that the solution structure progresses from planar to helical, and then to more intricate and complex filament structures, possibly indicating the onset of superfluid turbulence.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JGR...10518377W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JGR...10518377W"><span>Hall effects on the Walén relation in <span class="hlt">rotational</span> discontinuities and Alfvén <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, B. H.; Lee, L. C.</p> <p>2000-08-01</p> <p>For Alfvénic fluctuations in magnetohydrodynamics (MHD) the perturbed transverse velocity Vt and magnetic field Bt can be related by the Walén relation, Vt = ±Bt/(μ0ρ)1/2 ≡;±VAt, where ρ is the plasma density, VAt is the transverse Alfvén velocity, and the plus (minus) sign is for antiparallel (parallel) propagation. However, observations of Vt and Bt for Alfvén <span class="hlt">waves</span> and <span class="hlt">rotational</span> discontinuities in the solar wind and at the magnetopause showed an obvious deviation from the relation. In this paper, modifications of the Walén relation for linear and nonlinear Alfvén <span class="hlt">waves</span> and <span class="hlt">rotational</span> discontinuities (RDs) are examined in the Hall-MHD formulation. Let Vit (≈ Vt) be the transverse ion velocity and Vet be the transverse electron velocity. It is found that Vit = ±Bt(z)/(μ0ρ1)1/2 = ±(ρ(z)/ρ1)1/2 VAt(z) and Vet = ±(ρ1/μ0)1/2Bt(z)/ρ(z) = ±(ρ1/ρ(z))1/2 VAt(z)for RDs in Hall-MHD, where ρ1 is the upstream plasma density. The ion and electron Walén ratios are defined as Ai = Vit/VAt and Ae = Vet/VAt, respectively. It is found in Hall-MHD that ?, AiAe = 1 and Ai < 1 (Ai > 1) for Alfvén <span class="hlt">waves</span> and RDs with right-hand (left-hand) polarization. The Hall dispersive effect may modify the ion Walén ratio by ΔAi≈±0.14 for the magnetopause RDs and by ΔAi≈±0.07 for the interplanetary RDs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.tmp..185S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.tmp..185S"><span><span class="hlt">Rotational</span> motions from the 2016, Central Italy seismic sequence, as observed by an underground ring laser gyroscope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simonelli, A.; Igel, H.; Wassermann, J.; Belfi, J.; Di Virgilio, A.; Beverini, N.; De Luca, G.; Saccorotti, G.</p> <p>2018-05-01</p> <p>We present the analysis of <span class="hlt">rotational</span> and translational ground motions from earthquakes recorded during October/November, 2016, in association with the Central Italy seismic-sequence. We use co-located measurements of the vertical ground <span class="hlt">rotation</span> rate from a large ring laser gyroscope (RLG), and the three components of ground velocity from a broadband seismometer. Both instruments are positioned in a deep underground environment, within the Gran Sasso National Laboratories (LNGS) of the Istituto Nazionale di Fisica Nucleare (INFN). We collected dozens of events spanning the 3.5-5.9 Magnitude range, and epicentral distances between 30 km and 70 km. This data set constitutes an unprecedented observation of the vertical <span class="hlt">rotational</span> motions associated with an intense seismic sequence at local distance. Under the plane <span class="hlt">wave</span> <span class="hlt">approximation</span> we process the data set in order to get an experimental estimation of the events back azimuth. Peak values of <span class="hlt">rotation</span> rate (PRR) and horizontal acceleration (PGA) are markedly correlated, according to a scaling constant which is consistent with previous measurements from different earthquake sequences. We used a prediction model in use for Italy to calculate the expected PGA at the recording site, obtaining consequently predictions for PRR. Within the modeling uncertainties, predicted <span class="hlt">rotations</span> are consistent with the observed ones, suggesting the possibility of establishing specific attenuation models for ground <span class="hlt">rotations</span>, like the scaling of peak velocity and peak acceleration in empirical ground-motion prediction relationships. In a second step, after identifying the direction of the incoming <span class="hlt">wave</span>-field, we extract phase velocity data using the spectral ratio of the translational and <span class="hlt">rotational</span> components.. This analysis is performed over time windows associated with the P-coda, S-coda and Lg phase. Results are consistent with independent estimates of shear-<span class="hlt">wave</span> velocities in the shallow crust of the Central Apennines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720028687&hterms=short+film&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dshort%2Bfilm','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720028687&hterms=short+film&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dshort%2Bfilm"><span>Film stability in a vertical <span class="hlt">rotating</span> tube with a core-gas flow.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sarma, G. S. R.; Lu, P. C.; Ostrach, S.</p> <p>1971-01-01</p> <p>The linear hydrodynamic stability of a thin-liquid layer flowing along the inside wall of a vertical tube <span class="hlt">rotating</span> about its axis in the presence of a core-gas flow is examined. The stability problem is formulated under the conditions that the liquid film is thin, the density and viscosity ratios of gas to liquid are small and the relative (axial) pressure gradient in the gas is of the same order as gravity. The resulting eigenvalue problem is first solved by a perturbation method appropriate to axisymmetric long-<span class="hlt">wave</span> disturbances. The damped nature (to within the thin-film and other <span class="hlt">approximations</span> made) of the nonaxisymmetric and short-<span class="hlt">wave</span> disturbances is noted. In view of the limitations on a truncated perturbation solution when the disturbance wavenumber is not small, an initial value method using digital computer is presented. Stability characteristics of neutral, growing, and damped modes are presented showing the influences of <span class="hlt">rotation</span>, surface tension, and the core-gas flow. Energy balance in a neutral mode is also illustrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NJPh...20e5010L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NJPh...20e5010L"><span>Identical spin <span class="hlt">rotation</span> effect and electron spin <span class="hlt">waves</span> in quantum gas of atomic hydrogen</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lehtonen, L.; Vainio, O.; Ahokas, J.; Järvinen, J.; Novotny, S.; Sheludyakov, S.; Suominen, K.-A.; Vasiliev, S.; Khmelenko, V. V.; Lee, D. M.</p> <p>2018-05-01</p> <p>We present an experimental study of electron spin <span class="hlt">waves</span> in atomic hydrogen gas compressed to high densities of ∼5 × 1018 cm‑3 at temperatures ranging from 0.26 to 0.6 K in the strong magnetic field of 4.6 T. Hydrogen gas is in a quantum regime when the thermal de-Broglie wavelength is much larger than the s-<span class="hlt">wave</span> scattering length. In this regime the identical particle effects play a major role in atomic collisions and lead to the identical spin <span class="hlt">rotation</span> effect (ISR). We observed a variety of spin <span class="hlt">wave</span> modes caused by this effect with strong dependence on the magnetic potential caused by variations of the polarizing magnetic field. We demonstrate confinement of the ISR modes in the magnetic potential and manipulate their properties by changing the spatial profile of the magnetic field. We have found that at a high enough density of H gas the magnons accumulate in their ground state in the magnetic trap and exhibit long coherence, which has a profound effect on the electron spin resonance spectra. Such macroscopic accumulation of the ground state occurs at a certain critical density of hydrogen gas, where the chemical potential of the magnons becomes equal to the energy of their ground state in the trapping potential.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050175872&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwave%2Brotor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050175872&hterms=wave+rotor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwave%2Brotor"><span>Transient <span class="hlt">Wave</span> Rotor Performance Investigated</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1996-01-01</p> <p>The NASA Lewis Research Center is investigating the <span class="hlt">wave</span> rotor for use as a core gas generator in future gas turbine engines. The device, which uses gas-dynamic <span class="hlt">waves</span> to transfer energy directly to and from the working fluid through which the <span class="hlt">waves</span> travel, consists of a series of constant-area passages that <span class="hlt">rotate</span> about an axis. Through <span class="hlt">rotation</span>, the ends of the passages are periodically exposed to various circumferentially arranged ports that initiate the traveling <span class="hlt">waves</span> within the passages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOS.A34C2673S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOS.A34C2673S"><span><span class="hlt">Wave</span> Measurements in Landfast Ice in Svalbard: Evolution of <span class="hlt">Wave</span> Propagation following Wind <span class="hlt">Waves</span> to Swell Transition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sutherland, G.; Rabault, J.; Jensen, A.; Christensen, K. H.; Ward, B.; Marchenko, A. V.; Morozov, E.; Gundersen, O.; Halsne, T.; Lindstrøm, E.</p> <p>2016-02-01</p> <p>The impact of sea-ice cover on propagation of water <span class="hlt">waves</span> has been studied over five decades, both theoretically and from measurements on the ice. Understanding the interaction between water <span class="hlt">waves</span> and sea-ice covers is a topic of interest for a variety of purposes such as formulation of ocean models for climate, weather and sea state predictions, and the analysis of pollution dispersion in the Arctic. Our knowledge of the underlying phenomena is still partial, and more experimental data is required to gain further insight into the associated physics. Three Inertial Motion Units (IMUs) have been assessed in the lab and used to perform measurements on landfast ice over 2 days in Tempelfjorden, Svalbard during March 2015. The ice thickness in the measurement area was <span class="hlt">approximately</span> 60 to 80 cm. Two IMUs were located close to each other (6 meters) at a distance around 180 m from the ice edge. The third IMU was placed 120 m from the ice edge. The data collected contains a transition from high frequency, wind generated <span class="hlt">waves</span> to lower frequency swell. Drastic changes in <span class="hlt">wave</span> propagation are observed in relation with this transition. The level of reflected energy obtained from <span class="hlt">rotational</span> spectra is much higher before the transition to low frequency swell than later on. The correlation between the signal recorded by the IMU closer to the ice edge and the two others IMUs is low during the wind <span class="hlt">waves</span> dominated period, and increases with incoming swell. The dispersion relation for <span class="hlt">waves</span> in ice was found to correspond to flexural-gravity <span class="hlt">waves</span> before the transition and deepwater gravity <span class="hlt">waves</span> afterwards.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvL.117A1101C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvL.117A1101C"><span>Detecting <span class="hlt">Rotational</span> Superradiance in Fluid Laboratories</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cardoso, Vitor; Coutant, Antonin; Richartz, Mauricio; Weinfurtner, Silke</p> <p>2016-12-01</p> <p><span class="hlt">Rotational</span> superradiance was predicted theoretically decades ago, and is chiefly responsible for a number of important effects and phenomenology in black-hole physics. However, <span class="hlt">rotational</span> superradiance has never been observed experimentally. Here, with the aim of probing superradiance in the lab, we investigate the behavior of sound and surface <span class="hlt">waves</span> in fluids resting in a circular basin at the center of which a <span class="hlt">rotating</span> cylinder is placed. We show that with a suitable choice for the material of the cylinder, surface and sound <span class="hlt">waves</span> are amplified. Two types of instabilities are studied: one sets in whenever superradiant modes are confined near the <span class="hlt">rotating</span> cylinder and the other, which does not rely on confinement, corresponds to a local excitation of the cylinder. Our findings are experimentally testable in existing fluid laboratories and, hence, offer experimental exploration and comparison of dynamical instabilities arising from rapidly <span class="hlt">rotating</span> boundary layers in astrophysical as well as in fluid dynamical systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770009733','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770009733"><span><span class="hlt">Wave</span> refraction diagrams for the Baltimore Canyon region of the mid-Atlantic continental shelf computed by using three bottom topography <span class="hlt">approximation</span> techniques</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Poole, L. R.</p> <p>1976-01-01</p> <p>The Langley Research Center and Virginia Institute of Marine Science <span class="hlt">wave</span> refraction computer model was applied to the Baltimore Canyon region of the mid-Atlantic continental shelf. <span class="hlt">Wave</span> refraction diagrams for a wide range of normally expected <span class="hlt">wave</span> periods and directions were computed by using three bottom topography <span class="hlt">approximation</span> techniques: quadratic least squares, cubic least squares, and constrained bicubic interpolation. Mathematical or physical interpretation of certain features appearing in the computed diagrams is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3671R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3671R"><span>Atmospheric-like <span class="hlt">rotating</span> annulus experiment: gravity <span class="hlt">wave</span> emission from baroclinic jets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodda, Costanza; Borcia, Ion; Harlander, Uwe</p> <p>2017-04-01</p> <p>Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity <span class="hlt">waves</span> (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in <span class="hlt">rotating</span>- annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modelling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Joint laboratory experiment and numerical simulation have been conducted. The comparison between the data obtained from the experiment and the numerical simulations shows a very good</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18677363','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18677363"><span>Single-scatter vector-<span class="hlt">wave</span> scattering from surfaces with infinite slopes using the Kirchhoff <span class="hlt">approximation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bruce, Neil C</p> <p>2008-08-01</p> <p>This paper presents a new formulation of the 3D Kirchhoff <span class="hlt">approximation</span> that allows calculation of the scattering of vector <span class="hlt">waves</span> from 2D rough surfaces containing structures with infinite slopes. This type of surface has applications, for example, in remote sensing and in testing or imaging of printed circuits. Some preliminary calculations for rectangular-shaped grooves in a plane are presented for the 2D surface method and are compared with the equivalent 1D surface calculations for the Kirchhoff and integral equation methods. Good agreement is found between the methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004QJRMS.130.1977S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004QJRMS.130.1977S"><span>Agradient velocity, vortical motion and gravity <span class="hlt">waves</span> in a <span class="hlt">rotating</span> shallow-water model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sutyrin Georgi, G.</p> <p>2004-07-01</p> <p>A new approach to modelling slow vortical motion and fast inertia-gravity <span class="hlt">waves</span> is suggested within the <span class="hlt">rotating</span> shallow-water primitive equations with arbitrary topography. The velocity is exactly expressed as a sum of the gradient wind, described by the Bernoulli function,B, and the remaining agradient part, proportional to the velocity tendency. Then the equation for inverse potential vorticity,Q, as well as momentum equations for agradient velocity include the same source of intrinsic flow evolution expressed as a single term J (B, Q), where J is the Jacobian operator (for any steady state J (B, Q) = 0). Two components of agradient velocity are responsible for the fast inertia-gravity <span class="hlt">wave</span> propagation similar to the traditionally used divergence and ageostrophic vorticity. This approach allows for the construction of balance relations for vortical dynamics and potential vorticity inversion schemes even for moderate Rossby and Froude numbers assuming the characteristic value of |J(B, Q)| = to be small. The components of agradient velocity are used as the fast variables slaved to potential vorticity that allows for diagnostic estimates of the velocity tendency, the direct potential vorticity inversion with the accuracy of 2 and the corresponding potential vorticity-conserving agradient velocity balance model (AVBM). The ultimate limitations of constructing the balance are revealed in the form of the ellipticity condition for balanced tendency of the Bernoulli function which incorporates both known criteria of the formal stability: the gradient wind modified by the characteristic vortical Rossby <span class="hlt">wave</span> phase speed should be subcritical. The accuracy of the AVBM is illustrated by considering the linear normal modes and coastal Kelvin <span class="hlt">waves</span> in the f-plane channel with topography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNS21A1563C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNS21A1563C"><span>RoMi: Refraction Microtremor Using <span class="hlt">Rotational</span> Seismometers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clark, B.; Abbott, R. E.; Knox, H. A.; Eimer, M. O.; Hart, D. M.; Skaggs, J.; Denning, J. T.</p> <p>2013-12-01</p> <p>We present the results of a shallow shear-<span class="hlt">wave</span> velocity study that utilized both traditional geophones and a newly developed <span class="hlt">rotational</span> seismometer (Applied Technology Associates ARS-16). We used Refraction Microtremor (ReMi), a method developed by John N. Louie, during processing to determine both Rayleigh and Love <span class="hlt">wave</span> dispersion curves using both vertical and horizontal sources. ReMi uses a distance-time (x-t) wavefield transformation technique to image the dispersion curve in slowness-frequency (p-f) space. In the course of the ReMi processing, unwanted P <span class="hlt">waves</span> are transformed into p-f space. As <span class="hlt">rotational</span> seismometers are insensitive to P <span class="hlt">waves</span>, they should prove to be superior sensors for Love <span class="hlt">wave</span> studies, as those P <span class="hlt">waves</span> would not interfere with interpretation of the p-f wavefield. Our results show that despite having one-fifth the geophone signal-to-noise ratio in the distance-time wavefield, the ARS-16 produced superior results in the p-f wavefield. Specifically, we found increases of up to 50% in ReMi spectral ratio along the dispersion curve. This implies that as more quiet and sensitive <span class="hlt">rotational</span> sensors are developed, deploying <span class="hlt">rotational</span> seismometers instead of traditional sensors will yield significantly better results. This will ultimately improve shallow shear-<span class="hlt">wave</span> velocity resolution, which is vital for calculating seismic hazard. This data was collected at Sandia National Laboratories' Facility for Analysis, Calibration, and Testing (FACT) located in Albuquerque, NM. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850019493&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dfaraday','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850019493&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dfaraday"><span>The Faraday <span class="hlt">rotation</span> experiment. [solar corona</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Volland, H.; Levy, G. S.; Bird, M. K.; Stelzried, C. T.; Seidel, B. L.</p> <p>1984-01-01</p> <p>The magnetized plasma of the solar corona was remotely sounded using the Faraday <span class="hlt">rotation</span> effect. The solar magnetic field together with the electrons of the coronal plasma cause a measurable Faraday <span class="hlt">rotation</span> effect, since the radio <span class="hlt">waves</span> of Helios are linearly polarized. The measurement is performed at the ground stations. Alfven <span class="hlt">waves</span> traveling from the Sun's surface through the corona into interplanetary space are observed. Helios 2 signals penetrating through a region where coronal mass is ejected show wavelike structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApPhL.112q1111Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApPhL.112q1111Z"><span>Metasurface for multi-channel terahertz beam splitters and polarization <span class="hlt">rotators</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zang, XiaoFei; Gong, HanHong; Li, Zhen; Xie, JingYa; Cheng, QingQing; Chen, Lin; Shkurinov, Alexander P.; Zhu, YiMing; Zhuang, SongLin</p> <p>2018-04-01</p> <p>Terahertz beam splitters and polarization <span class="hlt">rotators</span> are two typical devices with wide applications ranging from terahertz communication to system integration. However, they are faced with severe challenges in manipulating THz <span class="hlt">waves</span> in multiple channels, which is desirable for system integration and device miniaturization. Here, we propose a method to design ultra-thin multi-channel THz beam splitters and polarization <span class="hlt">rotators</span> simultaneously. The reflected beams are divided into four beams with nearly the same density under illumination of linear-polarized THz <span class="hlt">waves</span>, while the polarization of reflected beams in each channel is modulated with a <span class="hlt">rotation</span> angle or invariable with respect to the incident THz <span class="hlt">waves</span>, leading to the multi-channel polarization <span class="hlt">rotator</span> (multiple polarization <span class="hlt">rotation</span> in the reflective channels) and beam splitter, respectively. Reflective metasurfaces, created by patterning metal-rods with different orientations on a polyimide film, were fabricated and measured to demonstrate these characteristics. The proposed approach provides an efficient way of controlling polarization of THz <span class="hlt">waves</span> in various channels, which significantly simplifies THz functional devices and the experimental system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...855...19I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...855...19I"><span>On the Vortex <span class="hlt">Waves</span> in Nonadiabatic Flows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ibáñez S., Miguel H.; Núñez, Luis A.</p> <p>2018-03-01</p> <p>Linear disturbances superposed on steady flows in nonadiabatic plasmas are analyzed. In addition to the potential modes resulting (two sound <span class="hlt">waves</span> and a thermal mode) that are Doppler shifted, a <span class="hlt">rotational</span> mode appears identified as an entropy-vortex <span class="hlt">wave</span> (evw) which is carried along by the gas flow. In adiabatic flows, as well as in nonadiabatic flows, the evw always shows a null pressure disturbance. But in the second case, the <span class="hlt">wave</span> number of the evw disturbance is fixed for the particular thermal conditions of the gas. The above holds for optically thin gases, as well as for radiating flows, if the dynamical effects of the radiation field are neglected in a first <span class="hlt">approximation</span>. The above results allow us to calculate the dimensions of the vortex elements that are expected to be formed in nonadiabatic gas flows, particularly in hot ionized plasmas of interest in astrophysics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/548840-eckhaus-benjamin-feir-instability-rotating-convection','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/548840-eckhaus-benjamin-feir-instability-rotating-convection"><span>Eckhaus-Benjamin-Feir Instability in <span class="hlt">Rotating</span> Convection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Liu, Y.; Ecke, R.E.</p> <p>1997-06-01</p> <p>We report experimental measurements of a traveling-<span class="hlt">wave</span> state in <span class="hlt">rotating</span> Rayleigh-B{acute e}nard convection. The fluid was water with a Prandtl number of 6.3 and a dimensionless <span class="hlt">rotation</span> rate of 274. The marginal and Eckhaus-Benjamin-Feir stability boundaries were determined and the local amplitude and <span class="hlt">wave</span> number were obtained from demodulation of shadowgraph images. The phase-diffusion coefficient and group velocity were measured in the stable <span class="hlt">wave</span> number band. This system was found to be well described by the one-dimensional complex Ginzburg-Landau equation. {copyright} {ital 1997} {ital The American Physical Society}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840030373&hterms=thought+experiments&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dthought%2Bexperiments','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840030373&hterms=thought+experiments&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dthought%2Bexperiments"><span><span class="hlt">Rotating</span>-fluid experiments with an atmospheric general circulation model</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Geisler, J. E.; Pitcher, E. J.; Malone, R. C.</p> <p>1983-01-01</p> <p>In order to determine features of <span class="hlt">rotating</span> fluid flow that are dependent on the geometry, <span class="hlt">rotating</span> annulus-type experiments are carried out with a numerical model in spherical coordinates. Rather than constructing and testing a model expressly for this purpose, it is found expedient to modify an existing general circulation model of the atmosphere by removing the model physics and replacing the lower boundary with a uniform surface. A regime diagram derived from these model experiments is presented; its major features are interpreted and contrasted with the major features of <span class="hlt">rotating</span> annulus regime diagrams. Within the <span class="hlt">wave</span> regime, a narrow region is found where one or two zonal <span class="hlt">wave</span> numbers are dominant. The results reveal no upper symmetric regime; <span class="hlt">wave</span> activity at low <span class="hlt">rotation</span> rates is thought to be maintained by barotropic rather than baroclinic processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19492124','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19492124"><span>Effects of reactant <span class="hlt">rotational</span> excitation on H + O2--> OH + O reaction rate constant: quantum <span class="hlt">wave</span> packet, quasi-classical trajectory and phase space theory calculations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Shi Ying; Guo, Hua; Lendvay, György; Xie, Daiqian</p> <p>2009-06-21</p> <p>We examine the impact of initial <span class="hlt">rotational</span> excitation on the reactivity of the H + O(2)--> OH + O reaction. Accurate Chebyshev <span class="hlt">wave</span> packet calculations have been carried out for the upsilon(i) = 0, j(i) = 9 initial state of O(2) and the J = 50 partial <span class="hlt">wave</span>. In addition, we present Gaussian-weighted quasi-classical trajectory and phase space theory calculations of the integral cross section and thermal rate constant for the title reaction. These theoretical results suggest that the initial <span class="hlt">rotational</span> excitation significantly enhances reactivity with an amount comparable to the effect of initial vibrational state excitation. The inclusion of internally excited reactants is shown to improve the agreement with experimental rate constant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S13B..02N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S13B..02N"><span>Mode cross coupling observations with a <span class="hlt">rotation</span> sensor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nader-Nieto, M. F.; Igel, H.; Ferreira, A. M.; Al-Attar, D.</p> <p>2013-12-01</p> <p>The Earth's free oscillations induced by large earthquakes have been one of the most important ways to measure the Earth's internal structure and processes. They provide important large scale constraints on a variety of elastic parameters, attenuation and density of the Earth's deep interior. The potential of <span class="hlt">rotational</span> seismic records for long period seismology was proven useful as a complement to traditional measurements in the study of the Earth's free oscillations. Thanks to the high resolution of the G-ring laser located at Geodetic Observatory Wettzell, Germany, we are now able to study the spectral energy generated by <span class="hlt">rotations</span> in the low frequency range. On a SNREI Earth, a vertical component <span class="hlt">rotational</span> sensor is primarily excited by horizontally polarised shear motions (SH <span class="hlt">waves</span>, Love <span class="hlt">waves</span>) with theoretically no sensitivity to compressional <span class="hlt">waves</span> and conversions (P-SV) and Rayleigh <span class="hlt">waves</span>. Consequently, in the context of the Earth's normal modes, this instrument detects mostly toroidal modes. Here, we present observations of spectral energy of both toroidal and spheroidal normal modes in the G-ring Laser records of one of the largest magnitude events recently recorded: Tohoku-Oki, Japan, 2011. In an attempt to determine the mechanisms responsible for spheroidal energy in the vertical axes <span class="hlt">rotational</span> spectra, we first rule out instrumental effects as well as the effect of local heterogeneity. Second, we carry out a simulation of an ideal <span class="hlt">rotational</span> sensor taking into account the effects of the Earth's daily <span class="hlt">rotation</span>, its hydrostatic ellipticity and structural heterogeneity, finding a good fit to the data. Simulations considering each effect separately are performed in order to evaluate the sensitivity of <span class="hlt">rotational</span> motions to global effects with respect to traditional translation measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatPh..13..833T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatPh..13..833T"><span><span class="hlt">Rotational</span> superradiant scattering in a vortex flow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Torres, Theo; Patrick, Sam; Coutant, Antonin; Richartz, Maurício; Tedford, Edmund W.; Weinfurtner, Silke</p> <p>2017-09-01</p> <p>When an incident <span class="hlt">wave</span> scatters off of an obstacle, it is partially reflected and partially transmitted. In theory, if the obstacle is <span class="hlt">rotating</span>, <span class="hlt">waves</span> can be amplified in the process, extracting energy from the scatterer. Here we describe in detail the first laboratory detection of this phenomenon, known as superradiance. We observed that <span class="hlt">waves</span> propagating on the surface of water can be amplified after being scattered by a draining vortex. The maximum amplification measured was 14% +/- 8%, obtained for 3.70 Hz <span class="hlt">waves</span>, in a 6.25-cm-deep fluid, consistent with the superradiant scattering caused by rapid <span class="hlt">rotation</span>. We expect our experimental findings to be relevant to black-hole physics, since shallow water <span class="hlt">waves</span> scattering on a draining fluid constitute an analogue of a black hole, as well as to hydrodynamics, due to the close relation to over-reflection instabilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvB..97k5402I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvB..97k5402I"><span>Counter-<span class="hlt">rotating</span> effects and entanglement dynamics in strongly coupled quantum-emitter-metallic-nanoparticle structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Iliopoulos, Nikos; Thanopulos, Ioannis; Yannopapas, Vassilios; Paspalakis, Emmanuel</p> <p>2018-03-01</p> <p>We study the spontaneous emission of a two-level quantum emitter next to a plasmonic nanoparticle beyond the Markovian <span class="hlt">approximation</span> and the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span> (RWA) by combining quantum dynamics and classical electromagnetic calculations. For emitters with decay times in the picosecond to nanosecond time regime, as well as located at distances from the nanoparticle up to its radius, the dynamics with and without the RWA and the transition from the non-Markovian to the Markovian regime are investigated. For emitters with longer decay times, the Markov <span class="hlt">approximation</span> proves to be adequate for distances larger than half the nanoparticle radius. However, the RWA is correct for all distances of the emitter from the nanoparticle. For short decay time emitters, the Markov <span class="hlt">approximation</span> and RWA are both inadequate, with only the RWA becoming valid again at a distance larger than half the nanoparticle radius. We also show that the entanglement dynamics of two initially entangled qubits interacting independently with the nanoparticle may have a strong non-Markovian character when counter-<span class="hlt">rotating</span> effects are included. Interesting effects such as entanglement sudden death, periodic entanglement revival, entanglement oscillations, and entanglement trapping are further observed when different initial two-qubit states and different distances between the qubit and the nanoparticle are considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21452660-quasi-biennial-oscillations-solar-tachocline-caused-magnetic-rossby-wave-instabilities','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21452660-quasi-biennial-oscillations-solar-tachocline-caused-magnetic-rossby-wave-instabilities"><span>QUASI-BIENNIAL OSCILLATIONS IN THE SOLAR TACHOCLINE CAUSED BY MAGNETIC ROSSBY <span class="hlt">WAVE</span> INSTABILITIES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zaqarashvili, Teimuraz V.; Carbonell, Marc; Oliver, Ramon</p> <p>2010-11-20</p> <p>Quasi-biennial oscillations (QBOs) are frequently observed in solar activity indices. However, no clear physical mechanism for the observed variations has been suggested so far. Here, we study the stability of magnetic Rossby <span class="hlt">waves</span> in the solar tachocline using the shallow water magnetohydrodynamic <span class="hlt">approximation</span>. Our analysis shows that the combination of typical differential <span class="hlt">rotation</span> and a toroidal magnetic field with a strength of {>=}10{sup 5} G triggers the instability of the m = 1 magnetic Rossby <span class="hlt">wave</span> harmonic with a period of {approx}2 years. This harmonic is antisymmetric with respect to the equator and its period (and growth rate) depends onmore » the differential <span class="hlt">rotation</span> parameters and magnetic field strength. The oscillations may cause a periodic magnetic flux emergence at the solar surface and consequently may lead to the observed QBO in solar activity features. The period of QBOs may change throughout a cycle, and from cycle to cycle, due to variations of the mean magnetic field and differential <span class="hlt">rotation</span> in the tachocline.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17356145','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17356145"><span>High-energy extracorporeal shock-<span class="hlt">wave</span> therapy for calcifying tendinitis of the <span class="hlt">rotator</span> cuff: a randomised trial.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Albert, J-D; Meadeb, J; Guggenbuhl, P; Marin, F; Benkalfate, T; Thomazeau, H; Chalès, G</p> <p>2007-03-01</p> <p>In a prospective randomised trial of calcifying tendinitis of the <span class="hlt">rotator</span> cuff, we compared the efficacy of dual treatment sessions delivering 2500 extracorporeal shock <span class="hlt">waves</span> at either high- or low-energy, via an electromagnetic generator under fluoroscopic guidance. Patients were eligible for the study if they had more than a three-month history of calcifying tendinitis of the <span class="hlt">rotator</span> cuff, with calcification measuring 10 mm or more in maximum dimension. The primary outcome measure was the change in the Constant and Murley Score. A total of 80 patients were enrolled (40 in each group), and were re-evaluated at a mean of 110 (41 to 255) days after treatment when the increase in Constant and Murley score was significantly greater (t-test, p = 0.026) in the high-energy treatment group than in the low-energy group. The improvement from the baseline level was significant in the high-energy group, with a mean gain of 12.5 (-20.7 to 47.5) points (p < 0.0001). The improvement was not significant in the low-energy group. Total or subtotal resorption of the calcification occurred in six patients (15%) in the high-energy group and in two patients (5%) in the low-energy group. High-energy shock-<span class="hlt">wave</span> therapy significantly improves symptoms in refractory calcifying tendinitis of the shoulder after three months of follow-up, but the calcific deposit remains unchanged in size in the majority of patients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NJPh...19l3003Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NJPh...19l3003Y"><span>Units of <span class="hlt">rotational</span> information</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Yuxiang; Chiribella, Giulio; Hu, Qinheping</p> <p>2017-12-01</p> <p>Entanglement in angular momentum degrees of freedom is a precious resource for quantum metrology and control. Here we study the conversions of this resource, focusing on Bell pairs of spin-J particles, where one particle is used to probe unknown <span class="hlt">rotations</span> and the other particle is used as reference. When a large number of pairs are given, we show that every <span class="hlt">rotated</span> spin-J Bell state can be reversibly converted into an equivalent number of <span class="hlt">rotated</span> spin one-half Bell states, at a rate determined by the quantum Fisher information. This result provides the foundation for the definition of an elementary unit of information about <span class="hlt">rotations</span> in space, which we call the Cartesian refbit. In the finite copy scenario, we design machines that <span class="hlt">approximately</span> break down Bell states of higher spins into Cartesian refbits, as well as machines that <span class="hlt">approximately</span> implement the inverse process. In addition, we establish a quantitative link between the conversion of Bell states and the simulation of unitary gates, showing that the fidelity of probabilistic state conversion provides upper and lower bounds on the fidelity of deterministic gate simulation. The result holds not only for <span class="hlt">rotation</span> gates, but also to all sets of gates that form finite-dimensional representations of compact groups. For <span class="hlt">rotation</span> gates, we show how <span class="hlt">rotations</span> on a system of given spin can simulate <span class="hlt">rotations</span> on a system of different spin.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24588169','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24588169"><span>Effects of reactant <span class="hlt">rotation</span> on the dynamics of the OH + CH4 → H2O + CH3 reaction: a six-dimensional study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Song, Hongwei; Li, Jun; Jiang, Bin; Yang, Minghui; Lu, Yunpeng; Guo, Hua</p> <p>2014-02-28</p> <p>The dynamics of the hydrogen abstraction reaction between methane and hydroxyl radical is investigated using an initial state selected time-dependent <span class="hlt">wave</span> packet method within a six-dimensional model. The ab initio calibrated global potential energy surface of Espinosa-García and Corchado was used. Integral cross sections from several low-lying <span class="hlt">rotational</span> states of both reactants have been obtained using the centrifugal sudden and J-shifting <span class="hlt">approximations</span>. On the empirical potential energy surface, the <span class="hlt">rotational</span> excitation of methane has little effect on the reaction cross section, but excited <span class="hlt">rotational</span> states of OH inhibit the reactivity slightly. These results are rationalized with the newly proposed sudden vector projection model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvA..97b3611K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvA..97b3611K"><span>Relationship between the transverse-field Ising model and the X Y model via the <span class="hlt">rotating-wave</span> <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kiely, Thomas G.; Freericks, J. K.</p> <p>2018-02-01</p> <p>In a large transverse field, there is an energy cost associated with flipping spins along the axis of the field. This penalty can be employed to relate the transverse-field Ising model in a large field to the X Y model in no field (when measurements are performed at the proper stroboscopic times). We describe the details for how this relationship works and, in particular, we also show under what circumstances it fails. We examine <span class="hlt">wave</span>-function overlap between the two models and observables, such as spin-spin Green's functions. In general, the mapping is quite robust at short times, but will ultimately fail if the run time becomes too long. There is also a tradeoff between the length of time one can run a simulation out to and the time jitter of the stroboscopic measurements that must be balanced when planning to employ this mapping.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMDI31B..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMDI31B..02M"><span>Characterisation of columnar inertial modes in rapidly <span class="hlt">rotating</span> spheres and spheroids</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maffei, S.; Jackson, A.; Livermore, P. W.</p> <p>2017-12-01</p> <p>We consider fluid-filled spheres and spheroidal containers of eccentricity ɛ in rapid <span class="hlt">rotation</span>, as a proxy for the interior dynamics of stars and planets. The fluid motion is assumed to be quasi-geostrophic (QG): horizontal motions are invariant parallel to the <span class="hlt">rotation</span> axis z, a characteristic which is handled by use of a stream function formulation which additionally enforces mass conservation and non-penetration at the boundary. By linearising about a quiescent background state, we investigate a variety of methods to study the QG inviscid inertial <span class="hlt">wave</span> modes which are compared with fully 3-D calculations. We consider the recently-proposed weak formulation of the inviscid system valid in spheroids of arbitrary eccentricity, to which we present novel closed-form polynomial solutions. Our modal solutions accurately represent, in both spatial structure and frequency, the most z-invariant of the inertial <span class="hlt">wave</span> modes in a spheroid, and constitute a simple basis set for the analysis of <span class="hlt">rotationally</span>- dominated fluids. We further show that these new solutions are more accurate than those of the classical axial-vorticity equation, which is independent of ɛ and thus fails to properly encode the container geometry. We also consider the effects of viscosity for the cases of both no-slip and stress-free boundary conditions for a spherical container. Calculations performed under the columnar <span class="hlt">approximation</span> are compared with 3-D solutions and excellent agreement has been found despite fundamental differences in the two formulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900000691','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900000691"><span>On the interaction of stationary crossflow vortices and Tollmien-Schlichting <span class="hlt">waves</span> in the boundary layer on a <span class="hlt">rotating</span> disc</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bassom, Andrew P.; Hall, Philip</p> <p>1989-01-01</p> <p>There are many fluid flows where the onset of transition can be caused by different instability mechanisms which compete among themselves. The interaction is considered of two types of instability mode (at an asymptotically large Reynolds number) which can occur in the flow above a <span class="hlt">rotating</span> disc. In particular, the interaction is examined between lower branch Tollmien-Schlichting (TS) <span class="hlt">waves</span> and the upper branch, stationary, inviscid crossflow vortex whose asymptotic structure has been described by Hall (1986). This problem is studied in the context of investigating the effect of the vortex on the stability characteristics of a small TS <span class="hlt">wave</span>. Essentially, it is found that the primary effect is felt through the modification to the mean flow induced by the presence of the vortex. Initially, the TS <span class="hlt">wave</span> is taken to be linear in character and it is shown (for the cases of both a linear and a nonlinear stationary vortex) that the vortex can exhibit both stabilizing and destabilizing effects on the TS <span class="hlt">wave</span> and the nature of this influence is wholly dependent upon the orientation of this latter instability. Further, the problem is examined with a larger TS <span class="hlt">wave</span>, whose size is chosen so as to ensure that this mode is nonlinear in its own right. An amplitude equation for the evolution of the TS <span class="hlt">wave</span> is derived which admits solutions corresponding to finite amplitude, stable, traveling <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1378920-improved-rotated-staggered-grid-finite-difference-method-fourth-order-temporal-accuracy-elastic-wave-modeling-anisotropic-media','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1378920-improved-rotated-staggered-grid-finite-difference-method-fourth-order-temporal-accuracy-elastic-wave-modeling-anisotropic-media"><span>An improved <span class="hlt">rotated</span> staggered-grid finite-difference method with fourth-order temporal accuracy for elastic-<span class="hlt">wave</span> modeling in anisotropic media</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Gao, Kai; Huang, Lianjie</p> <p>2017-08-31</p> <p>The <span class="hlt">rotated</span> staggered-grid (RSG) finite-difference method is a powerful tool for elastic-<span class="hlt">wave</span> modeling in 2D anisotropic media where the symmetry axes of anisotropy are not aligned with the coordinate axes. We develop an improved RSG scheme with fourth-order temporal accuracy to reduce the numerical dispersion associated with prolonged <span class="hlt">wave</span> propagation or a large temporal step size. The high-order temporal accuracy is achieved by including high-order temporal derivatives, which can be converted to high-order spatial derivatives to reduce computational cost. Dispersion analysis and numerical tests show that our method exhibits very low temporal dispersion even with a large temporal step sizemore » for elastic-<span class="hlt">wave</span> modeling in complex anisotropic media. Using the same temporal step size, our method is more accurate than the conventional RSG scheme. In conclusion, our improved RSG scheme is therefore suitable for prolonged modeling of elastic-<span class="hlt">wave</span> propagation in 2D anisotropic media.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1378920-improved-rotated-staggered-grid-finite-difference-method-fourth-order-temporal-accuracy-elastic-wave-modeling-anisotropic-media','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1378920-improved-rotated-staggered-grid-finite-difference-method-fourth-order-temporal-accuracy-elastic-wave-modeling-anisotropic-media"><span>An improved <span class="hlt">rotated</span> staggered-grid finite-difference method with fourth-order temporal accuracy for elastic-<span class="hlt">wave</span> modeling in anisotropic media</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Gao, Kai; Huang, Lianjie</p> <p></p> <p>The <span class="hlt">rotated</span> staggered-grid (RSG) finite-difference method is a powerful tool for elastic-<span class="hlt">wave</span> modeling in 2D anisotropic media where the symmetry axes of anisotropy are not aligned with the coordinate axes. We develop an improved RSG scheme with fourth-order temporal accuracy to reduce the numerical dispersion associated with prolonged <span class="hlt">wave</span> propagation or a large temporal step size. The high-order temporal accuracy is achieved by including high-order temporal derivatives, which can be converted to high-order spatial derivatives to reduce computational cost. Dispersion analysis and numerical tests show that our method exhibits very low temporal dispersion even with a large temporal step sizemore » for elastic-<span class="hlt">wave</span> modeling in complex anisotropic media. Using the same temporal step size, our method is more accurate than the conventional RSG scheme. In conclusion, our improved RSG scheme is therefore suitable for prolonged modeling of elastic-<span class="hlt">wave</span> propagation in 2D anisotropic media.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016A%26A...587A.126B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016A%26A...587A.126B"><span>Weak magnetic field, solid-envelope <span class="hlt">rotation</span>, and <span class="hlt">wave</span>-induced N-enrichment in the SPB star ζ Cassiopeiae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Briquet, M.; Neiner, C.; Petit, P.; Leroy, B.; de Batz, B.</p> <p>2016-03-01</p> <p>Aims: The main-sequence B-type star ζ Cassiopeiae is known as a N-rich star with a magnetic field discovered with the Musicos spectropolarimeter. We model the magnetic field of the star by means of 82 new spectropolarimetric observations of higher precision to investigate the field strength, topology, and effect. Methods: We gathered data with the Narval spectropolarimeter installed at Télescope Bernard Lyot (TBL; Pic du Midi, France) and applied the least-squares deconvolution technique to measure the circular polarisation of the light emitted from ζ Cas. We used a dipole oblique <span class="hlt">rotator</span> model to determine the field configuration by fitting the longitudinal field measurements and by synthesizing the measured Stokes V profiles. We also made use of the Zeeman-Doppler imaging technique to map the stellar surface and to deduce the difference in <span class="hlt">rotation</span> rate between the pole and equator. Results: ζ Cas exhibits a polar field strength Bpol of 100-150 G, which is the weakest polar field observed so far in a massive main-sequence star. Surface differential <span class="hlt">rotation</span> is ruled out by our observations and the field of ζ Cas is strong enough to enforce rigid internal <span class="hlt">rotation</span> in the radiative zone according to theory. Thus, the star <span class="hlt">rotates</span> as a solid body in the envelope. Conclusions: We therefore exclude <span class="hlt">rotationally</span> induced mixing as the cause of the surface N-enrichment. We discuss that the transport of chemicals from the core to the surface by internal gravity <span class="hlt">waves</span> is the most plausible explanation for the nitrogen overabundance at the surface of ζ Cas. Based on observations obtained at the Télescope Bernard Lyot (USR5026) operated by the Observatoire Midi-Pyrénées, Université de Toulouse (Paul Sabatier), Centre National de la Recherche Scientifique (CNRS) of France.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhyEd..51a5014P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhyEd..51a5014P"><span><span class="hlt">Rotating</span> swings—a theme with variations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pendrill, Ann-Marie</p> <p>2016-01-01</p> <p><span class="hlt">Rotating</span> swing rides can be found in many amusement parks, in many different versions. The ‘<span class="hlt">wave</span> swinger’ ride, which introduces a <span class="hlt">wave</span> motion by tilting the roof, is among the classical amusement rides that are found in many different parks, in different sizes, from a number of different makes and names, and varying thematization. The ‘StarFlyer’ is a more recent version, adding the thrill of lifting the riders 60 m or more over the ground. These <span class="hlt">rotating</span> swing rides involve beautiful physics, often surprising, but easily observed, when brought to attention. The rides can be used for student worksheet tasks and assignments of different degrees of difficulty, across many math and physics topics. This paper presents a number of variations of student tasks relating to the theme of <span class="hlt">rotating</span> swing rides.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5555135-interpretation-es-cs-ios-approximations-within-translational-internal-coupling-scheme-ii-application-atom-diatom-kinetic-cross-sections','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5555135-interpretation-es-cs-ios-approximations-within-translational-internal-coupling-scheme-ii-application-atom-diatom-kinetic-cross-sections"><span>Interpretation of ES, CS, and IOS <span class="hlt">approximations</span> within a translational-internal coupling scheme. II. Application to atom--diatom kinetic cross sections</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Coombe, D.A.; Snider, R.F.</p> <p>1980-02-15</p> <p>ES, CS, and IOS <span class="hlt">approximations</span> to atom--diatom kinetic cross sections are derived. In doing so, reduced S-matrices in a translational-internal coupling scheme are stressed. This entails the insertion of recently obtained <span class="hlt">approximate</span> reduced S-matrices in the translational-internal coupling scheme into previously derived general expressions for the kinetic cross sections. Of special interest is the structure (<span class="hlt">rotational</span> j quantum number dependence) of the kinetic cross sections associated with the Senftleben Beenakker effects and of pure internal state relaxation phenomena. The viscomagnetic effect is used as an illustrative example. It is found in particular that there is a great similarity of structuremore » between the energy sudden (and IOS) <span class="hlt">approximation</span> and the previously derived distorted <span class="hlt">wave</span> Born results.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..GECGT1175S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..GECGT1175S"><span>Trajectory Control of Small <span class="hlt">Rotating</span> Projectiles by Laser Sparks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Starikovskiy, Andrey; Limbach, Christopher; Miles, Richard</p> <p>2015-09-01</p> <p>The possibility of controlling the trajectory of the supersonic motion of a <span class="hlt">rotating</span> axisymmetric projectile using a remotely generated laser spark was investigated. The dynamic images of the interaction of thermal inhomogeneity created by the laser spark with the bow shock in front of the projectile were obtained. The criterion for a strong shock <span class="hlt">wave</span> interaction with the thermal inhomogeneity at different angles of a shock <span class="hlt">wave</span> was derived. Significant changes in the configuration of the bow shock <span class="hlt">wave</span> and changes in the pressure distribution over the surface of the <span class="hlt">rotating</span> projectile can appear for laser spark temperature of T' = 2500-3000 K. The experiment showed that strong interaction takes place for both plane and oblique shock <span class="hlt">waves</span>. The measurement of the velocity of the precession of the <span class="hlt">rotating</span> projectile axis from the initial position in time showed that the angle of attack of the projectile deviates with a typical time of perturbation propagation along the projectile's surface. Thus the laser spark can change the trajectory of the <span class="hlt">rotating</span> projectile, moving at supersonic speed, through the creation of thermal heterogeneity in front of it.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IAUFM..29B.509P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IAUFM..29B.509P"><span>Spectroscopic mode identification of γ Doradus stars: frequencies, modes, <span class="hlt">rotation</span> and <span class="hlt">wave</span> leakage</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pollard, Karen R.; Brunsden, E.; Davie, M.; Greenwood, A.; Cottrell, P. L.</p> <p></p> <p>The gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. The MUSICIAN programme at the University of Canterbury has been successfully identifying frequencies and pulsation modes in many γ Doradus stars using hundreds of precise, high resolution spectroscopic observations obtained with the 1.0 m telescope and HERCULES spectrograph at the Mt John Observatory in New Zealand. In this paper we present a summary of our spectroscopic frequency and mode identifications. Of particular interest from our spectroscopic analyses are: the prevalence of (l, m) = 1, 1 modes in many γ Dor stars; the importance of stellar <span class="hlt">rotation</span> in the interpretation of the frequency and mode identification; and finally, possible evidence of <span class="hlt">wave</span> leakage in one of these stars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EL.....9844004Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EL.....9844004Z"><span>The effect of an infinite plane-<span class="hlt">wave</span> <span class="hlt">approximation</span> on calculations for second-harmonic generation in a one-dimensional nonlinear crystal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Jing; Zhao, Li-Ming</p> <p>2012-05-01</p> <p>In this paper, the second-harmonic generation (SHG) in a one-dimensional nonlinear crystal that is embedded in air is investigated. Previously, the identical configuration was studied in Li Z. Y. et al., Phys. Rev. B, 60 (1999) 10644, without the use of the slowly varying amplitude <span class="hlt">approximation</span> (SVAA), but by adopting the infinite plane-<span class="hlt">wave</span> <span class="hlt">approximation</span> (PWA), despite the fact that this <span class="hlt">approximation</span> is not quite applicable to such a system. We calculate the SHG conversion efficiency without a PWA, and compare the results with those from the quoted reference. The investigation reveals that conversion efficiencies of SHG as calculated by the two methods appear to exhibit significant differences, and that the SHG may be modulated by the field of a fundamental <span class="hlt">wave</span> (FW). The ratio between SHG conversion efficiencies as produced by the two methods shows a periodic variation, and this oscillatory behavior is fully consistent with the variation in transmittance of the FW. Quasi-phase matching (QPM) is also studied, and we find that the location of the peak for SHG conversion efficiency deviates from Δd=0, which differs from the conventional QPM results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1510303N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1510303N"><span>Mode cross coupling observations with a <span class="hlt">rotation</span> sensor.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nader, Maria-Fernanda; Igel, Heiner; Ferreira, Ana M. G.; Al-Attar, David</p> <p>2013-04-01</p> <p>The Earth's free oscillations induced by large earthquakes have been one of the most important ways to measure the Earth's internal structure and processes. They provide important large scale constraints on a variety of elastic parameters, attenuation and density of the Earth's deep interior. The potential of <span class="hlt">rotational</span> seismic records for long period seismology was proven useful as a complement to traditional measurements in the study of the Earth's free oscillations (Igel et al. 2011). Thanks to the high resolution of the G-ring laser located at Geodetic Observatory Wettzell, Germany, we are now able to study the spectral energy generated by <span class="hlt">rotations</span> in the low frequency range. On a SNREI Earth, a vertical component <span class="hlt">rotational</span> sensor is primarily excited by horizontally polarised shear motions (SH <span class="hlt">waves</span>, Love <span class="hlt">waves</span>) with theoretically no sensitivity to compressional <span class="hlt">waves</span> and conversions (P-SV) and Rayleigh <span class="hlt">waves</span>. Consequently, in the context of the Earth's normal modes, this instrument detects mostly toroidal modes. Here, we present observations of spectral energy of both toroidal and spheroidal normal modes in the G-ring Laser records of two of the largest magnitude events recently recorded: Tohoku-Oki, Japan, 2011 and Maule, Chile, 2010. In an attempt to determine the mechanisms responsible for spheroidal energy in the vertical axes <span class="hlt">rotational</span> spectra, we first rule out instrumental effects as well as the effect of local heterogeneity. Second, we carry out a simulation of an ideal <span class="hlt">rotational</span> sensor taking into account the effects of the Earth's daily <span class="hlt">rotation</span>, its hydrostatic ellipticity and structural heterogeneity, finding a good fit to the data. Simulations considering each effect separately are performed in order to evaluate the sensitivity of <span class="hlt">rotational</span> motions to global effects with respect to traditional translation measurements. Igel H, Nader MF, Kurrle D, Ferreira AM,Wassermann J, Schreiber KU (2011) ''Observations of Earth's toroidal free</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950052130&hterms=hinson&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dhinson','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950052130&hterms=hinson&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dhinson"><span>Magellan radio occultation measurements of atmospheric <span class="hlt">waves</span> on Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hinson, David P.; Jenkins, J. M.</p> <p>1995-01-01</p> <p>Radio occultation experiments were conducted at Venus on three consecutive orbits of the Magellan spacecraft in October 1991. Each occultation occurred over the same topography (67 deg N, 127 deg E) and at the same local time (22 hr 5 min), but the data are sensitive to zonal variations because the atmosphere <span class="hlt">rotates</span> significantly during one orbit. Through comparisons between observations and predictions of standard <span class="hlt">wave</span> theory, we have demonstrated that small-scale oscillations in retrieved temperature profiles as well as scintillations in received signal intensity are caused by a spectrum of vertically propagating internal gravity <span class="hlt">waves</span>. There is a strong similarity between the intensity scintillations observed here and previous measurements, which pertain to a wide range of locations and experiment dates. This implies that the same basic phenomenon underlies all the observations and hence that gravity <span class="hlt">waves</span> are a persistent, global feature of Venus' atmosphere. We obtained a fairly complete characterization of a gravity <span class="hlt">wave</span> that appears above the middle cloud in temperature measurements on all three orbits. The amplitude and vertical wavelength are about 4 K and 2.5 km respectively, at 65 km. A model for radiative damping implies that the <span class="hlt">wave</span> intrinsic frequency is <span class="hlt">approximately</span> 2 x 10(exp 4) rad/sec, the corresponding ratio between horizontal and vertical wavelengths is <span class="hlt">approximately</span> 100. The <span class="hlt">wave</span> is nearly stationary relative to the surface or the Sun. Radiative attenuation limits the <span class="hlt">wave</span> amplitude at altitudes above <span class="hlt">approximately</span> 65 km, leading to <span class="hlt">wave</span> drag on the mean zonal winds of about +0.4 m/sec per day (eastward). The sign, magnitude, and location of this forcing suggest a possible role in explaining the decrease with height in the zonal wind speed that is believed to occur above the cloud tops. Temperature oscillations with larger vertical wavelengths (5-10 km) were also observed on all three orbits, but we are able unable to interpret these</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JSV...420...35C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JSV...420...35C"><span>Nonlinear vibrations analysis of <span class="hlt">rotating</span> drum-disk coupling structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chaofeng, Li; Boqing, Miao; Qiansheng, Tang; Chenyang, Xi; Bangchun, Wen</p> <p>2018-04-01</p> <p>A dynamic model of a coupled <span class="hlt">rotating</span> drum-disk system with elastic support is developed in this paper. By considering the effects of centrifugal and Coriolis forces as well as <span class="hlt">rotation</span>-induced hoop stress, the governing differential equation of the drum-disk is derived by Donnell's shell theory. The nonlinear amplitude-frequency characteristics of coupled structure are studied. The results indicate that the natural characteristics of the coupling structure are sensitive to the supporting stiffness of the disk, and the sensitive range is affected by <span class="hlt">rotating</span> speeds. The circumferential <span class="hlt">wave</span> numbers can affect the characteristics of the drum-disk structure. If the circumferential <span class="hlt">wave</span> number n = 1 , the vibration response of the drum keeps a stable value under an unbalanced load of the disk, there is no coupling effect if n ≠ 1 . Under the excitation, the nonlinear hardening characteristics of the forward traveling <span class="hlt">wave</span> are more evident than that of the backward traveling <span class="hlt">wave</span>. Moreover, because of the coupling effect of the drum and the disk, the supporting stiffness of the disk has certain effect on the nonlinear characteristics of the forward and backward traveling <span class="hlt">waves</span>. In addition, small length-radius and thickness-radius ratios have a significant effect on the nonlinear characteristics of the coupled structure, which means nonlinear shell theory should be adopted to design <span class="hlt">rotating</span> drum's parameter for its specific structural parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011APS..DFDE26005D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011APS..DFDE26005D"><span>Vortex formation through inertial <span class="hlt">wave</span> focusing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duran-Matute, Matias; Flor, Jan-Bert; Godeferd, Fabien</p> <p>2011-11-01</p> <p>We present a novel experimental and numerical study on the formation of columnar vortical structures by inertial <span class="hlt">waves</span> in a <span class="hlt">rotating</span> fluid. Two inertial-<span class="hlt">wave</span> cones are generated by a vertically oscillating torus in a fluid in solid body <span class="hlt">rotation</span> At the tip of the cones, there is a singular point towards which the energy of the <span class="hlt">waves</span> gets focused. The particularity of this configuration, as compared to those of previous experiments (e.g. oscillating sphere or disc), is that the singular point's position within the fluid leads to complex non-linear <span class="hlt">wave</span> interaction, which may lead to the formation of a localized vortex that expands in the vertical in the form of a Taylor column. Using detailed PIV measurements we consider the flow evolution from the localized <span class="hlt">wave</span> overturning motion to the Taylor column formation as well as the inertial <span class="hlt">wave</span> dynamics during this process, The results are discussed in the context of turbulence in <span class="hlt">rotating</span> fluids. We acknowledge financial support from projects ANR ANISO and CIBLE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18282036','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18282036"><span><span class="hlt">Rotational</span> excitations in para-H2+para-H2 collisions: full- and reduced-dimensional quantum <span class="hlt">wave</span> packet studies comparing different potential energy surfaces.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Otto, Frank; Gatti, Fabien; Meyer, Hans-Dieter</p> <p>2008-02-14</p> <p>We study the process of <span class="hlt">rotational</span> excitation in the collisions of para-H(2) with para-H(2) by propagating <span class="hlt">wave</span> packets with the multiconfiguration time-dependent Hartree (MCTDH) algorithm. Transition probabilities are then calculated by the method of Tannor and Weeks based on time-correlation functions. Calculations were carried out up to a total angular momentum of J=70 to compute integral cross sections up to 1.2 eV in collision energy and thermal rate coefficients from 100 to 3000 K. The process is studied on the full-dimensional potential energy surface of Boothroyd-Martin-Keogh-Peterson (BMKP) as well as on the rigid rotor surface of Diep and Johnson. We test the validity of the rigid rotor <span class="hlt">approximation</span> by also considering two rigid rotor restrictions of the BMKP potential energy surface (PES). Additionally, we investigate a variant of the BMKP PES suggested by Pogrebnya and Clary [Chem. Phys. Lett. 363, 523 (2002)] with reduced anisotropy. We compare our results with previous theoretical data for the cross sections and with experimental data for the rate coefficients at low temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010055266','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010055266"><span><span class="hlt">Wave</span> Augmented Diffuser for Centrifugal Compressor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Skoch, Gary J. (Inventor); Paxson, Daniel E. (Inventor)</p> <p>2001-01-01</p> <p>A <span class="hlt">wave</span> augmented diffuser for a centrifugal compressor surrounds the outlet of an impeller that <span class="hlt">rotates</span> on a drive shaft having an axis of <span class="hlt">rotation</span>. The impeller brings flow in in an axial direction and imparts kinetic energy to the flow discharging it in radial and tangential directions. The flow is discharged into a plurality of circumferentially disposed <span class="hlt">wave</span> chambers. The <span class="hlt">wave</span> chambers are periodically opened and closed by a rotary valve such that the flow through the diffuser is unsteady. The valve includes a plurality of valve openings that are periodically brought into and out of fluid communication with the <span class="hlt">wave</span> chambers. When the <span class="hlt">wave</span> chambers are closed, a reflected compression <span class="hlt">wave</span> moves upstream towards the diffuser bringing the flow into the <span class="hlt">wave</span> chamber to rest. This action recovers the kinetic energy from the flow and limits any boundary layer growth. The flow is then discharged in an axial direction through an opening in the valve plate when the valve plate is <span class="hlt">rotated</span> to an open position. The diffuser thus efficiently raises the static pressure of the fluid and discharges an axially directed flow at a radius that is predominantly below the maximum radius of the diffuser.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040030512&hterms=Kohn&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DKohn','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040030512&hterms=Kohn&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DKohn"><span><span class="hlt">Approximating</span> the Helium Wavefunction in Positronium-Helium Scattering</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>DiRienzi, Joseph; Drachman, Richard J.</p> <p>2003-01-01</p> <p>In the Kohn variational treatment of the positronium- hydrogen scattering problem the scattering <span class="hlt">wave</span> function is <span class="hlt">approximated</span> by an expansion in some appropriate basis set, but the target and projectile <span class="hlt">wave</span> functions are known exactly. In the positronium-helium case, however, a difficulty immediately arises in that the <span class="hlt">wave</span> function of the helium target atom is not known exactly, and there are several ways to deal with the associated eigenvalue in formulating the variational scattering equations to be solved. In this work we will use the Kohn variational principle in the static exchange <span class="hlt">approximation</span> to d e t e e the zero-energy scattering length for the Ps-He system, using a suite of <span class="hlt">approximate</span> target functions. The results we obtain will be compared with each other and with corresponding values found by other <span class="hlt">approximation</span> techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012CSR....35..108W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012CSR....35..108W"><span>Radiation stress and mean drift in continental shelf <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weber, Jan Erik H.; Drivdal, Magnus</p> <p>2012-03-01</p> <p>The time- and depth-averaged mean drift induced by barotropic continental shelf <span class="hlt">waves</span> (CSW's) is studied theoretically for idealized shelf topography by calculating the mean volume fluxes to second order in <span class="hlt">wave</span> amplitude. The <span class="hlt">waves</span> suffer weak spatial damping due to bottom friction, which leads to radiation stress forcing of the mean fluxes. In terms of the total <span class="hlt">wave</span> energy density E̅̅ over the shelf region, the radiation stress tensor component S̅11 for CSW's is found to be different from that of shallow water surface <span class="hlt">waves</span> in a non-<span class="hlt">rotating</span> ocean. For CSW's, the ratio S̅11/E̅ depends strongly on the <span class="hlt">wave</span> number. The mean Lagrangian flow forced by the radiation stress can be subdivided into a Stokes drift and a mean Eulerian drift current. The magnitude of latter depends on ratio between the radiation stress and the bottom stress acting on the mean flow. When the effect of bottom friction acts equally strong on the <span class="hlt">waves</span> and the mean current, calculations for short CSW's show that the Stokes drift and the friction-dependent <span class="hlt">wave</span>-induced mean Eulerian current varies <span class="hlt">approximately</span> in anti-phase over the shelf, and that the latter is numerically the largest. For long CSW's they are <span class="hlt">approximately</span> in phase. In both cases the mean Lagrangian current, which is responsible for the net particle drift, has its largest numerical value at the coast on the shallow part of the shelf. Enhancing the effect of bottom friction on the Eulerian mean flow, results in a general current speed reduction, as well as a change in spatial structure for long <span class="hlt">waves</span>. Applying realistic physical parameters for the continental shelf west of Norway, calculations yield along-shelf mean drift velocities for short CSW's that may be important for the transport of biological material, neutral tracers, and underwater plumes of dissolved oil from deepwater drilling accidents.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.2640X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.2640X"><span>Directional Absorption of Parameterized Mountain <span class="hlt">Waves</span> and Its Influence on the <span class="hlt">Wave</span> Momentum Transport in the Northern Hemisphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Xin; Tang, Ying; Wang, Yuan; Xue, Ming</p> <p>2018-03-01</p> <p>The directional absorption of mountain <span class="hlt">waves</span> in the Northern Hemisphere is assessed by examination of horizontal wind <span class="hlt">rotation</span> using the 2.5° × 2.5° European Centre for Medium-Range Weather Forecasts ERA-Interim reanalysis between 2011 and 2016. In the deep layer of troposphere and stratosphere, the horizontal wind <span class="hlt">rotates</span> by more than 120° all over the Northern Hemisphere primary mountainous areas, with the <span class="hlt">rotation</span> mainly occurring in the troposphere (stratosphere) of lower (middle to high) latitudes. The <span class="hlt">rotation</span> of tropospheric wind increases markedly in summer over the Tibetan Plateau and Iranian Plateau, due to the influence of Asian summer monsoonal circulation. The influence of directional absorption of mountain <span class="hlt">waves</span> on the mountain <span class="hlt">wave</span> momentum transport is also studied using a new parameterization scheme of orographic gravity <span class="hlt">wave</span> drag (OGWD) which accounts for the effect of directional wind shear. Owing to the directional absorption, the <span class="hlt">wave</span> momentum flux is attenuated by more than 50% in the troposphere of lower latitudes, producing considerable orographic gravity <span class="hlt">wave</span> lift which is normal to the mean wind. Compared with the OGWD produced in traditional schemes assuming a unidirectional wind profile, the OGWD in the new scheme is suppressed in the lower stratosphere but enhanced in the upper stratosphere and lower mesosphere. This is because the directional absorption of mountain <span class="hlt">waves</span> in the troposphere reduces the <span class="hlt">wave</span> amplitude in the stratosphere. Consequently, mountain <span class="hlt">waves</span> are prone to break at higher altitudes, which favors the production of stronger OGWD given the decrease of air density with height.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA343354','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA343354"><span>Proceedings of the International Conference "Quantum Optics IV" Jaszowiec, Poland, June 17-24, 1997. Volume 93, Number 1</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1998-01-01</p> <p>and creation operators of the radiation mode of frequency win. The interaction (in the <span class="hlt">rotating</span> <span class="hlt">wave</span> <span class="hlt">approximation</span> ) is described by Am =• x10)(1llat...based on a series of approx- imations [such as the <span class="hlt">rotating</span> <span class="hlt">wave</span> <span class="hlt">approximation</span> (RWA) and the "pole" approxi- mation (PA)] validity of which is...possibly, the oscillating dependencies ti(eo) and r(eo) arise when and because one does not use the <span class="hlt">rotating</span> - <span class="hlt">wave</span> and pole <span class="hlt">approximations</span> inherently present</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29229797','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29229797"><span>Capturing the flow beneath water <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nachbin, A; Ribeiro-Junior, R</p> <p>2018-01-28</p> <p>Recently, the authors presented two numerical studies for capturing the flow structure beneath water <span class="hlt">waves</span> (Nachbin and Ribeiro-Junior 2014 Disc. Cont. Dyn. Syst. A 34 , 3135-3153 (doi:10.3934/dcds.2014.34.3135); Ribeiro-Junior et al. 2017 J. Fluid Mech. 812 , 792-814 (doi:10.1017/jfm.2016.820)). Closed orbits for irrotational <span class="hlt">waves</span> with an opposing current and stagnation points for <span class="hlt">rotational</span> <span class="hlt">waves</span> were some of the issues addressed. This paper summarizes the numerical strategies adopted for capturing the flow beneath irrotational and <span class="hlt">rotational</span> water <span class="hlt">waves</span>. It also presents new preliminary results for particle trajectories, due to irrotational <span class="hlt">waves</span>, in the presence of a bottom topography.This article is part of the theme issue 'Nonlinear water <span class="hlt">waves</span>'. © 2017 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1412096D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1412096D"><span>Mean Lagrangian drift in continental shelf <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Drivdal, M.; Weber, J. E. H.</p> <p>2012-04-01</p> <p>The time- and depth-averaged mean drift induced by barotropic continental shelf <span class="hlt">waves</span> (CSW's) is studied theoretically for idealized shelf topography by calculating the mean volume fluxes to second order in <span class="hlt">wave</span> amplitude. The <span class="hlt">waves</span> suffer weak spatial damping due to bottom friction, which leads to radiation stress forcing of the mean fluxes. In terms of the total <span class="hlt">wave</span> energy density E¯ over the shelf region, the radiation stress tensor component S¯11 for CSW's is found to be different from that of shallow water surface <span class="hlt">waves</span> in a non-<span class="hlt">rotating</span> ocean. For CSW's, the ratio ¯S11/¯E depends strongly on the <span class="hlt">wave</span> number. The mean Lagrangian flow forced by the radiation stress can be subdivided into a Stokes drift and a mean Eulerian drift current. The magnitude of the latter depends on the ratio between the radiation stress and the bottom stress acting on the mean flow. When the effect of bottom friction acts equally strong on the <span class="hlt">waves</span> and the mean current, calculations for short CSW's show that the Stokes drift and the friction-dependent <span class="hlt">wave</span>-induced mean Eulerian current varies <span class="hlt">approximately</span> in anti-phase over the shelf, and that the latter is numerically the largest. For long CSW's they are <span class="hlt">approximately</span> in phase. In both cases the mean Lagrangian current, which is responsible for the net particle drift, has its largest numerical value at the coast on the shallow part of the shelf. Enhancing the effect of bottom friction on the Eulerian mean flow, results in a general current speed reduction, as well as a change in spatial structure for long <span class="hlt">waves</span>. Applying realistic physical parameters for the continental shelf west of Norway, calculations yield along-shelf mean drift velocities for short CSW's that may be important for the transport of biological material, neutral tracers, and underwater plumes of dissolved oil from deep water drilling accidents.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T31E..05C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T31E..05C"><span>Nonlinear Solver Approaches for the Diffusive <span class="hlt">Wave</span> <span class="hlt">Approximation</span> to the Shallow Water Equations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Collier, N.; Knepley, M.</p> <p>2015-12-01</p> <p>The diffusive <span class="hlt">wave</span> <span class="hlt">approximation</span> to the shallow water equations (DSW) is a doubly-degenerate, nonlinear, parabolic partial differential equation used to model overland flows. Despite its challenges, the DSW equation has been extensively used to model the overland flow component of various integrated surface/subsurface models. The equation's complications become increasingly problematic when ponding occurs, a feature which becomes pervasive when solving on large domains with realistic terrain. In this talk I discuss the various forms and regularizations of the DSW equation and highlight their effect on the solvability of the nonlinear system. In addition to this analysis, I present results of a numerical study which tests the applicability of a class of composable nonlinear algebraic solvers recently added to the Portable, Extensible, Toolkit for Scientific Computation (PETSc).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22617281-nonlinear-wave-interactions-shallow-water-magnetohydrodynamics-astrophysical-plasma','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22617281-nonlinear-wave-interactions-shallow-water-magnetohydrodynamics-astrophysical-plasma"><span>Nonlinear <span class="hlt">wave</span> interactions in shallow water magnetohydrodynamics of astrophysical plasma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Klimachkov, D. A., E-mail: klimachkovdmitry@gmail.com; Petrosyan, A. S., E-mail: apetrosy@iki.rssi.ru</p> <p>2016-05-15</p> <p>The <span class="hlt">rotating</span> magnetohydrodynamic flows of a thin layer of astrophysical and space plasmas with a free surface in a vertical external magnetic field are considered in the shallow water <span class="hlt">approximation</span>. The presence of a vertical external magnetic field changes significantly the dynamics of <span class="hlt">wave</span> processes in an astrophysical plasma, in contrast to a neutral fluid and a plasma layer in an external toroidal magnetic field. There are three-<span class="hlt">wave</span> nonlinear interactions in the case under consideration. Using the asymptotic method of multiscale expansions, we have derived nonlinear equations for the interaction of <span class="hlt">wave</span> packets: three magneto- Poincare <span class="hlt">waves</span>, three magnetostrophic <span class="hlt">waves</span>,more » two magneto-Poincare and one magnetostrophic <span class="hlt">waves</span>, and two magnetostrophic and one magneto-Poincare <span class="hlt">waves</span>. The existence of decay instabilities and parametric amplification is predicted. We show that a magneto-Poincare <span class="hlt">wave</span> decays into two magneto-Poincare <span class="hlt">waves</span>, a magnetostrophic <span class="hlt">wave</span> decays into two magnetostrophic <span class="hlt">waves</span>, a magneto-Poincare <span class="hlt">wave</span> decays into one magneto-Poincare and one magnetostrophic <span class="hlt">waves</span>, and a magnetostrophic <span class="hlt">wave</span> decays into one magnetostrophic and one magneto-Poincare <span class="hlt">waves</span>. There are the following parametric amplification mechanisms: the parametric amplification of magneto-Poincare <span class="hlt">waves</span>, the parametric amplification of magnetostrophic <span class="hlt">waves</span>, the amplification of a magneto-Poincare <span class="hlt">wave</span> in the field of a magnetostrophic <span class="hlt">wave</span>, and the amplification of a magnetostrophic <span class="hlt">wave</span> in the field of a magneto-Poincare <span class="hlt">wave</span>. The instability growth rates and parametric amplification factors have been found for the corresponding processes.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24580333','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24580333"><span>Nonlinear dynamics and anisotropic structure of <span class="hlt">rotating</span> sheared turbulence.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Salhi, A; Jacobitz, F G; Schneider, K; Cambon, C</p> <p>2014-01-01</p> <p>Homogeneous turbulence in <span class="hlt">rotating</span> shear flows is studied by means of pseudospectral direct numerical simulation and analytical spectral linear theory (SLT). The ratio of the Coriolis parameter to shear rate is varied over a wide range by changing the <span class="hlt">rotation</span> strength, while a constant moderate shear rate is used to enable significant contributions to the nonlinear interscale energy transfer and to the nonlinear intercomponental redistribution terms. In the destabilized and neutral cases, in the sense of kinetic energy evolution, nonlinearity cannot saturate the growth of the largest scales. It permits the smallest scale to stabilize by a scale-by-scale quasibalance between the nonlinear energy transfer and the dissipation spectrum. In the stabilized cases, the role of <span class="hlt">rotation</span> is mainly nonlinear, and interacting inertial <span class="hlt">waves</span> can affect almost all scales as in purely <span class="hlt">rotating</span> flows. In order to isolate the nonlinear effect of <span class="hlt">rotation</span>, the two-dimensional manifold with vanishing spanwise <span class="hlt">wave</span> number is revisited and both two-component spectra and single-point two-dimensional energy components exhibit an important effect of <span class="hlt">rotation</span>, whereas the SLT as well as the purely two-dimensional nonlinear analysis are unaffected by <span class="hlt">rotation</span> as stated by the Proudman theorem. The other two-dimensional manifold with vanishing streamwise <span class="hlt">wave</span> number is analyzed with similar tools because it is essential for any shear flow. Finally, the spectral approach is used to disentangle, in an analytical way, the linear and nonlinear terms in the dynamical equations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4814581','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4814581"><span><span class="hlt">Rotational</span> manipulation of single cells and organisms using acoustic <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun</p> <p>2016-01-01</p> <p>The precise <span class="hlt">rotational</span> manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can <span class="hlt">rotate</span> single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely <span class="hlt">rotate</span> colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic <span class="hlt">rotational</span> manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting <span class="hlt">rotation</span> regardless of optical, magnetic or electrical properties of the sample under investigation. PMID:27004764</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27004764','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27004764"><span><span class="hlt">Rotational</span> manipulation of single cells and organisms using acoustic <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ahmed, Daniel; Ozcelik, Adem; Bojanala, Nagagireesh; Nama, Nitesh; Upadhyay, Awani; Chen, Yuchao; Hanna-Rose, Wendy; Huang, Tony Jun</p> <p>2016-03-23</p> <p>The precise <span class="hlt">rotational</span> manipulation of single cells or organisms is invaluable to many applications in biology, chemistry, physics and medicine. In this article, we describe an acoustic-based, on-chip manipulation method that can <span class="hlt">rotate</span> single microparticles, cells and organisms. To achieve this, we trapped microbubbles within predefined sidewall microcavities inside a microchannel. In an acoustic field, trapped microbubbles were driven into oscillatory motion generating steady microvortices which were utilized to precisely <span class="hlt">rotate</span> colloids, cells and entire organisms (that is, C. elegans). We have tested the capabilities of our method by analysing reproductive system pathologies and nervous system morphology in C. elegans. Using our device, we revealed the underlying abnormal cell fusion causing defective vulval morphology in mutant worms. Our acoustofluidic <span class="hlt">rotational</span> manipulation (ARM) technique is an easy-to-use, compact, and biocompatible method, permitting <span class="hlt">rotation</span> regardless of optical, magnetic or electrical properties of the sample under investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23405276','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23405276"><span>Ultra high energy electrons powered by pulsar <span class="hlt">rotation</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mahajan, Swadesh; Machabeli, George; Osmanov, Zaza; Chkheidze, Nino</p> <p>2013-01-01</p> <p>A new mechanism of particle acceleration, driven by the <span class="hlt">rotational</span> slow down of the Crab pulsar, is explored. The <span class="hlt">rotation</span>, through the time dependent centrifugal force, can efficiently excite unstable Langmuir <span class="hlt">waves</span> in the electron-positron (hereafter e(±)) plasma of the star magnetosphere. These <span class="hlt">waves</span>, then, Landau damp on electrons accelerating them in the process. The net transfer of energy is optimal when the <span class="hlt">wave</span> growth and the Landau damping times are comparable and are both very short compared to the star <span class="hlt">rotation</span> time. We show, by detailed calculations, that these are precisely the conditions for the parameters of the Crab pulsar. This highly efficient route for energy transfer allows the electrons in the primary beam to be catapulted to multiple TeV (~ 100 TeV) and even PeV energy domain. It is expected that the proposed mechanism may, unravel the puzzle of the origin of ultra high energy cosmic ray electrons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22676058-emission-angle-polarization-rotation-effects-lensed-cmb','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22676058-emission-angle-polarization-rotation-effects-lensed-cmb"><span>Emission-angle and polarization-<span class="hlt">rotation</span> effects in the lensed CMB</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lewis, Antony; Hall, Alex; Challinor, Anthony, E-mail: antony@cosmologist.info, E-mail: ahall@roe.ac.uk, E-mail: a.d.challinor@ast.cam.ac.uk</p> <p></p> <p>Lensing of the CMB is an important effect, and is usually modelled by remapping the unlensed CMB fields by a lensing deflection. However the lensing deflections also change the photon path so that the emission angle is no longer orthogonal to the background last-scattering surface. We give the first calculation of the emission-angle corrections to the standard lensing <span class="hlt">approximation</span> from dipole (Doppler) sources for temperature and quadrupole sources for temperature and polarization. We show that while the corrections are negligible for the temperature and E-mode polarization, additional large-scale B-modes are produced with a white spectrum that dominates those from post-Bornmore » field <span class="hlt">rotation</span> (curl lensing). On large scales about one percent of the total lensing-induced B-mode amplitude is expected to be due to this effect. However, the photon emission angle does remain orthogonal to the perturbed last-scattering surface due to time delay, and half of the large-scale emission-angle B modes cancel with B modes from time delay to give a total contribution of about half a percent. While not important for planned observations, the signal could ultimately limit the ability of delensing to reveal low amplitudes of primordial gravitational <span class="hlt">waves</span>. We also derive the <span class="hlt">rotation</span> of polarization due to multiple deflections between emission and observation. The <span class="hlt">rotation</span> angle is of quadratic order in the deflection angle, and hence negligibly small: polarization typically <span class="hlt">rotates</span> by less than an arcsecond, orders of magnitude less than a small-scale image <span class="hlt">rotates</span> due to post-Born field <span class="hlt">rotation</span> (which is quadratic in the shear). The field-<span class="hlt">rotation</span> B modes dominate the other effects on small scales.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA00724&hterms=Wave+filter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DWave%2Bfilter','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA00724&hterms=Wave+filter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DWave%2Bfilter"><span>Mesoscale <span class="hlt">Waves</span> in Jupiter's Atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1997-01-01</p> <p>These two images of Jupiter's atmosphere were taken with the violet filter of the Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft. The images were obtained on June 26, 1996; the lower image was taken <span class="hlt">approximately</span> one <span class="hlt">rotation</span> (9 hours) later than the upper image.<p/>Mesoscale <span class="hlt">waves</span> can be seen in the center of the upper image. They appear as a series of about 15 nearly vertical stripes; the <span class="hlt">wave</span> crests are aligned north-south. The <span class="hlt">wave</span> packet is about 300 kilometers in length and is aligned east-west. In the lower image there is no indication of the <span class="hlt">waves</span>, though the clouds appear to have been disturbed. Such <span class="hlt">waves</span> were seen also in images obtained by NASA's Voyager spacecraft in 1979, though lower spatial and time resolution made tracking of features such as these nearly impossible.<p/>Mesoscale <span class="hlt">waves</span> occur when the wind shear is strong in an atmospheric layer that is sandwiched vertically between zones of stable stratification. The orientation of the <span class="hlt">wave</span> crests is perpendicular to the shear. Thus, a <span class="hlt">wave</span> observation gives information about how the wind direction changes with height in the atmosphere.<p/>North is at the top of these images which are centered at <span class="hlt">approximately</span> 15 South latitude and 307 West longitude. In the upper image, each picture element (pixel) subtends a square of about 36 kilometers on a side, and the spacecraft was at a range of more than 1.7 million kilometers from Jupiter. In the lower image, each pixel subtends a square of about 30 kilometers on a side, and the spacecraft was at a range of more than 1.4 million kilometers from Jupiter.<p/>The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.<p/>This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AIPC.1953f0011S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AIPC.1953f0011S"><span>Jeans instability of <span class="hlt">rotating</span> magnetized dusty plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sharma, S.; Sutar, D. L.; Kumar, V.; Pensia, R. K.</p> <p>2018-05-01</p> <p>It has been shown that <span class="hlt">rotation</span> has to play a predominant important role in the formation of many astrophysical objects and the stability of molecular clouds. In this paper the theoretical investigation of the presence of <span class="hlt">rotation</span> in the magnetized dusty plasma. The general dispersion relation is obtained normal mode analysis technique, and we found the Alfven mode is modified due to the presence of <span class="hlt">rotation</span> and magnetic field. The graphical presentation shows that <span class="hlt">rotation</span> and Alfven <span class="hlt">wave</span> velocity have a stabilizing in the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16671673','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16671673"><span>Coriolis-coupled <span class="hlt">wave</span> packet dynamics of H + HLi reaction.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Padmanaban, R; Mahapatra, S</p> <p>2006-05-11</p> <p>We investigated the effect of Coriolis coupling (CC) on the initial state-selected dynamics of H+HLi reaction by a time-dependent <span class="hlt">wave</span> packet (WP) approach. Exact quantum scattering calculations were obtained by a WP propagation method based on the Chebyshev polynomial scheme and ab initio potential energy surface of the reacting system. Partial <span class="hlt">wave</span> contributions up to the total angular momentum J=30 were found to be necessary for the scattering of HLi in its vibrational and <span class="hlt">rotational</span> ground state up to a collision energy <span class="hlt">approximately</span> 0.75 eV. For each J value, the projection quantum number K was varied from 0 to min (J, K(max)), with K(max)=8 until J=20 and K(max)=4 for further higher J values. This is because further higher values of K do not have much effect on the dynamics and also because one wishes to maintain the large computational overhead for each calculation within the affordable limit. The initial state-selected integral reaction cross sections and thermal rate constants were calculated by summing up the contributions from all partial <span class="hlt">waves</span>. These were compared with our previous results on the title system, obtained within the centrifugal sudden and J-shifting <span class="hlt">approximations</span>, to demonstrate the impact of CC on the dynamics of this system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27973892','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27973892"><span>Beyond Kohn-Sham <span class="hlt">Approximation</span>: Hybrid Multistate <span class="hlt">Wave</span> Function and Density Functional Theory.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gao, Jiali; Grofe, Adam; Ren, Haisheng; Bao, Peng</p> <p>2016-12-15</p> <p>A multistate density functional theory (MSDFT) is presented in which the energies and densities for the ground and excited states are treated on the same footing using multiconfigurational approaches. The method can be applied to systems with strong correlation and to correctly describe the dimensionality of the conical intersections between strongly coupled dissociative potential energy surfaces. A dynamic-then-static framework for treating electron correlation is developed to first incorporate dynamic correlation into contracted state functions through block-localized Kohn-Sham density functional theory (KSDFT), followed by diagonalization of the effective Hamiltonian to include static correlation. MSDFT can be regarded as a hybrid of <span class="hlt">wave</span> function and density functional theory. The method is built on and makes use of the current <span class="hlt">approximate</span> density functional developed in KSDFT, yet it retains its computational efficiency to treat strongly correlated systems that are problematic for KSDFT but too large for accurate WFT. The results presented in this work show that MSDFT can be applied to photochemical processes involving conical intersections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730014018','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730014018"><span>Transverse low frequency <span class="hlt">wave</span> in a two fluid solar wind. M.S. Thesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Solodyna, G. V.</p> <p>1973-01-01</p> <p>Investigation is made of the properties of low frequency transverse <span class="hlt">waves</span> in a two-fluid solar wind having a radial magnetic field and radial streaming velocity. In order to examine what effects this streaming medium has on the <span class="hlt">waves</span>, linearly polarized <span class="hlt">waves</span> are decomposed into left and right circularly polarized <span class="hlt">waves</span>. Computation is made of analytic expressions valid to first order for the radial amplitude and phase dependence of these constituent <span class="hlt">waves</span>. It is shown that after travelling a given distance r, these <span class="hlt">waves</span> have different amplitudes and phases. The former result causes their superposition to become elliptical rather than linear. The latter causes the axis of the ellipse of polarization to <span class="hlt">rotate</span> through a well-defined angle. Analytic expressions are obtained for the eccentricity of the ellipse and for the angle of <span class="hlt">rotation</span>. In analogy with regular Faraday <span class="hlt">rotation</span>, in which the plane of polarization of a linear polarized <span class="hlt">wave</span> <span class="hlt">rotates</span>, the effect is denoted as generalized Faraday <span class="hlt">rotation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/879770','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/879770"><span>Traveling <span class="hlt">wave</span> device for combining or splitting symmetric and asymmetric <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Möbius, Arnold; Ives, Robert Lawrence</p> <p>2005-07-19</p> <p>A traveling <span class="hlt">wave</span> device for the combining or splitting of symmetric and asymmetric traveling <span class="hlt">wave</span> energy includes a feed waveguide for traveling <span class="hlt">wave</span> energy, the feed waveguide having an input port and a launching port, a reflector for coupling <span class="hlt">wave</span> energy between the feed waveguide and a final waveguide for the collection and transport of <span class="hlt">wave</span> energy to or from the reflector. The power combiner has a launching port for symmetrical <span class="hlt">waves</span> which includes a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric <span class="hlt">waves</span> which includes a sawtooth <span class="hlt">rotated</span> about a central axis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21408642-control-dephasing-rotationally-hot-molecules','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21408642-control-dephasing-rotationally-hot-molecules"><span>Control of dephasing in <span class="hlt">rotationally</span> hot molecules</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Bartram, David; Ivanov, Misha</p> <p></p> <p>We consider a <span class="hlt">rotationally</span> hot diatomic molecule as an example of an open quantum system, where molecular vibrational <span class="hlt">wave</span> packets are subject to dephasing due to rovibrational coupling. We report analytical and numerical results addressing whether the dephasing rate can be controlled by adjustment of the initial <span class="hlt">wave</span> packet phases. It appears that over long time scales, phase-only control is not possible, but for earlier time scales the possibility of phase-only control of dephasing remains. In addition, we point out that the time dependence of the dephasing process depends significantly upon the degeneracy of the <span class="hlt">rotational</span> environment states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG14A..06F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG14A..06F"><span>Homogeneous <span class="hlt">wave</span> turbulence driven by tidal flows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Favier, B.; Le Reun, T.; Barker, A.; Le Bars, M.</p> <p>2017-12-01</p> <p>When a moon orbits around a planet, the <span class="hlt">rotation</span> of the induced tidal bulge drives a homogeneous, periodic, large-scale flow. The combination of such an excitation with the <span class="hlt">rotating</span> motion of the planet has been shown to drive parametric resonance of a pair of inertial <span class="hlt">waves</span> in a mechanism called the elliptical instability. Geophysical fluid layers can also be stratified: this is the case for instance of the Earth's oceans and, as suggested by several studies, of the upper part of the Earth's liquid Outer Core. We thus investigate the stability of a <span class="hlt">rotating</span> and stratified layer undergoing tidal distortion in the limit where either <span class="hlt">rotation</span> or stratification is dominant. We show that the periodic tidal flow drives a parametric subharmonic resonance of inertial (resp. internal) <span class="hlt">waves</span> in the <span class="hlt">rotating</span> (resp. stratified) case. The instability saturates into a <span class="hlt">wave</span> turbulence pervading the whole fluid layer. In such a state, the instability mechanism conveys the tidal energy from the large scale tidal flow to the resonant modes, which then feed a succession of triadic resonances also generating small spatial scales. In the <span class="hlt">rotating</span> case, we observe a kinetic energy spectrum with a k-2 slope for which the Coriolis force is dominant at all spatial scales. In the stratified case, where the timescale separation is increased between the tidal excitation and the Brunt-Väisälä frequencies, the temporal spectrum decays with a ω-2 power law up to the cut-off frequency beyond which <span class="hlt">waves</span> do not exist. This result is reminiscent of the Garrett and Munk spectrum measured in the oceans and theoretically described as a manifestation of internal <span class="hlt">wave</span> turbulence. In addition to revealing an instability driving homogeneous turbulence in geophysical fluid layers, our approach is also an efficient numerical tool to investigate the possibly universal properties of <span class="hlt">wave</span> turbulence in a geophysical context.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016InJPh..90.1055N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016InJPh..90.1055N"><span>Propagation of exponential shock <span class="hlt">wave</span> in an axisymmetric <span class="hlt">rotating</span> non-ideal dusty gas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nath, G.</p> <p>2016-09-01</p> <p>One-dimensional unsteady isothermal and adiabatic flow behind a strong exponential shock <span class="hlt">wave</span> propagating in a <span class="hlt">rotational</span> axisymmetric mixture of non-ideal gas and small solid particles, which has variable azimuthal and axial fluid velocities, is analyzed. The shock <span class="hlt">wave</span> is driven out by a piston moving with time according to exponential law. The azimuthal and axial components of the fluid velocity in the ambient medium are assumed to be varying and obeying exponential laws. In the present work, small solid particles are considered as pseudo-fluid with the assumption that the equilibrium flow-conditions are maintained in the flow-field, and the viscous-stress and heat conduction of the mixture are negligible. Solutions are obtained in both the cases, when the flow between the shock and the piston is isothermal or adiabatic by taking into account the components of vorticity vector and compressibility. It is found that the assumption of zero temperature gradient brings a profound change in the density, axial component of vorticity vector and compressibility distributions as compared to that of the adiabatic case. To investigate the behavior of the flow variables and the influence on the shock <span class="hlt">wave</span> propagation by the parameter of non-idealness of the gas overline{b} in the mixture as well as by the mass concentration of solid particles in the mixture Kp and by the ratio of the density of solid particles to the initial density of the gas G1 are worked out in detail. It is interesting to note that the shock strength increases with an increase in G1 ; whereas it decreases with an increase in overline{b} . Also, a comparison between the solutions in the cases of isothermal and adiabatic flows is made.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002532&hterms=lech&qs=N%3D0%26Ntk%3DAuthor-Name%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dlech','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002532&hterms=lech&qs=N%3D0%26Ntk%3DAuthor-Name%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dlech"><span>Millimetre <span class="hlt">Wave</span> <span class="hlt">Rotational</span> Spectrum of Glycolic Acid</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kisiel, Zbigniew; Pszczolkowski, Lech; Bialkowska-Jaworska, Ewa; Charnley, Steven B.</p> <p>2016-01-01</p> <p>The pure <span class="hlt">rotational</span> spectrum of glycolic acid, CH2OHCOOH, was studied in the region 115-318 GHz. For the most stable SSC conformer, transitions in all vibrational states up to 400 cm(exp -1) have been measured and their analysis is reported. The data sets for the ground state, v21 = 1, and v21 = 2 have been considerably extended. Immediately higher in vibrational energy are two triads of interacting vibrational states and their <span class="hlt">rotational</span> transitions have been assigned and successfully fitted with coupled Hamiltonians accounting for Fermi and Coriolis resonances. The derived energy level spacings establish that the vibrational frequency of the v21 mode is close to 100 cm(exp -1). The existence of the less stable AAT conformer in the near 50 C sample used in our experiment was also confirmed and additional transitions have been measured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRC..119.6952Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRC..119.6952Z"><span>A numerical investigation of <span class="hlt">wave</span>-breaking-induced turbulent coherent structure under a solitary <span class="hlt">wave</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhou, Zheyu; Sangermano, Jacob; Hsu, Tian-Jian; Ting, Francis C. K.</p> <p>2014-10-01</p> <p>To better understand the effect of <span class="hlt">wave</span>-breaking-induced turbulence on the bed, we report a 3-D large-eddy simulation (LES) study of a breaking solitary <span class="hlt">wave</span> in spilling condition. Using a turbulence-resolving approach, we study the generation and the fate of <span class="hlt">wave</span>-breaking-induced turbulent coherent structures, commonly known as obliquely descending eddies (ODEs). Specifically, we focus on how these eddies may impinge onto bed. The numerical model is implemented using an open-source CFD library of solvers, called OpenFOAM, where the incompressible 3-D filtered Navier-Stokes equations for the water and the air phases are solved with a finite volume scheme. The evolution of the water-air interfaces is <span class="hlt">approximated</span> with a volume of fluid method. Using the dynamic Smagorinsky closure, the numerical model has been validated with <span class="hlt">wave</span> flume experiments of solitary <span class="hlt">wave</span> breaking over a 1/50 sloping beach. Simulation results show that during the initial overturning of the breaking <span class="hlt">wave</span>, 2-D horizontal rollers are generated, accelerated, and further evolve into a couple of 3-D hairpin vortices. Some of these vortices are sufficiently intense to impinge onto the bed. These hairpin vortices possess counter-<span class="hlt">rotating</span> and downburst features, which are key characteristics of ODEs observed by earlier laboratory studies using Particle Image Velocimetry. Model results also suggest that those ODEs that impinge onto bed can induce strong near-bed turbulence and bottom stress. The intensity and locations of these near-bed turbulent events could not be parameterized by near-surface (or depth integrated) turbulence unless in very shallow depth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017DPS....4911528G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017DPS....4911528G"><span>Infrared <span class="hlt">rotational</span> light curves on Jupiter induced by <span class="hlt">wave</span> activities and cloud patterns andimplications on brown dwarfs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ge, Huazhi; Zhang, Xi; Fletcher, Leigh; Orton, Glenn S.; Sinclair, James Andrew; Fernandes,, Joshua; Momary, Thomas W.; Warren, Ari; Kasaba, Yasumasa; Sato, Takao M.; Fujiyoshi, Takuya</p> <p>2017-10-01</p> <p>Many brown dwarfs exhibit infrared <span class="hlt">rotational</span> light curves with amplitude varying from a fewpercent to twenty percent (Artigau et al. 2009, ApJ, 701, 1534; Radigan et al. 2012, ApJ, 750,105). Recently, it was claimed that weather patterns, especially planetary-scale <span class="hlt">waves</span> in thebelts and cloud spots, are responsible for the light curves and their evolutions on brown dwarfs(Apai et al. 2017, Science, 357, 683). Here we present a clear relationship between the direct IRemission maps and light curves of Jupiter at multiple wavelengths, which might be similar withthat on cold brown dwarfs. Based on infrared disk maps from Subaru/COMICS and VLT/VISIR,we constructed full maps of Jupiter and <span class="hlt">rotational</span> light curves at different wavelengths in thethermal infrared. We discovered a strong relationship between the light curves and weatherpatterns on Jupiter. The light curves also exhibit strong multi-bands phase shifts and temporalvariations, similar to that detected on brown dwarfs. Together with the spectra fromTEXES/IRTF, our observations further provide detailed information of the spatial variations oftemperature, ammonia clouds and aerosols in the troposphere of Jupiter (Fletcher et al. 2016,Icarus, 2016 128) and their influences on the shapes of the light curves. We conclude that waveactivities in Jupiter’s belts (Fletcher et al. 2017, GRL, 44, 7140), cloud holes, and long-livedvortices such as the Great Red Spot and ovals control the shapes of IR light curves and multi-wavelength phase shifts on Jupiter. Our finding supports the hypothesis that observed lightcurves on brown dwarfs are induced by planetary-scale <span class="hlt">waves</span> and cloud spots.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AAS...23126104T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AAS...23126104T"><span>Modeling of the response of the POLARBEAR bolometers with a continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takakura, Satoru; POLARBEAR Collaboration</p> <p>2018-01-01</p> <p>The curly pattern, the so-called B-mode, in the polarization anisotropy of the cosmic microwave background (CMB) is a powerful probe to measure primordial gravitational <span class="hlt">waves</span> from the cosmic inflation, as well as the weak lensing due to the large scale structure of the Universe. At present, ground-based CMB experiments with a few arcminutes resolution such as POLARBEAR, SPTpol, and ACTPol have successfully measured the angular power spectrum of the B-mode only in sub-degree scales, though these experiments also have potential to measure the inflationary B-modes in degree scales in absence of the low-frequency noise (1/f noise). Thus, techniques of polarization signal modulation such as a continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate (CRHWP) are widely investigated to suppress the 1/f noise and also to reduce instrumental systematic errors. In this study, we have implemented a CRHWP placed around the prime focus of the POLARBEAR telescope and operated at ambient temperatures. We construct a comprehensive model including half-<span class="hlt">wave</span> plate synchronous signals, detector non-linearities, beam imperfections, and all noise sources. Using this model, we show that, in practice, the 1/f noise and instrumental systematics could remain even with the CRHWP. However, we also evaluate those effects from test observations using a prototype CRHWP on the POLARBEAR telescope and find that the residual 1/f noise is sufficiently small for POLARBEAR to probe the multipoles about 40. We will also discuss prospects for future CMB experiments with better sensitivities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JEPT...90..187N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JEPT...90..187N"><span>Nonsimilar Solution for Shock <span class="hlt">Waves</span> in a <span class="hlt">Rotational</span> Axisymmetric Perfect Gas with a Magnetic Field and Exponentially Varying Density</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nath, G.; Sinha, A. K.</p> <p>2017-01-01</p> <p>The propagation of a cylindrical shock <span class="hlt">wave</span> in an ideal gas in the presence of a constant azimuthal magnetic field with consideration for the axisymmetric <span class="hlt">rotational</span> effects is investigated. The ambient medium is assumed to have the radial, axial, and azimuthal velocity components. The fluid velocities and density of the ambient medium are assumed to vary according to an exponential law. Nonsimilar solutions are obtained by taking into account the vorticity vector and its components. The dependences of the characteristics of the problem on the Alfven-Mach number and time are obtained. It is shown that the presence of a magnetic field has a decaying effect on the shock <span class="hlt">wave</span>. The pressure and density are shown to vanish at the inner surface (piston), and hence a vacuum forms at the line of symmetry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyEd..50..560K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyEd..50..560K"><span>A simple <span class="hlt">wave</span> driver</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kağan Temiz, Burak; Yavuz, Ahmet</p> <p>2015-08-01</p> <p>This study was done to develop a simple and inexpensive <span class="hlt">wave</span> driver that can be used in experiments on string <span class="hlt">waves</span>. The <span class="hlt">wave</span> driver was made using a battery-operated toy car, and the apparatus can be used to produce string <span class="hlt">waves</span> at a fixed frequency. The working principle of the apparatus is as follows: shortly after the car is turned on, the wheel starts to turn at a constant angular speed. A rod that is fixed on the wheel turns at the same constant angular speed, too. A tight string that the <span class="hlt">wave</span> will be created on is placed at a distance where the rod can touch the string. During each <span class="hlt">rotation</span> of the wheel, the rod vibrates the string up and down. The vibration frequency of this rod equals the wheel’s <span class="hlt">rotation</span> frequency, and this frequency value can be measured easily with a small magnet and a bicycle speedometer. In this way, the frequency of the <span class="hlt">waves</span> formed in the rope can also be measured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6075366-ocean-wave-electric-generators','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6075366-ocean-wave-electric-generators"><span>Ocean <span class="hlt">wave</span> electric generators</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Rosenberg, H.R.</p> <p></p> <p>This patent describes an apparatus for generating electricity from ocean <span class="hlt">waves</span>. It consists of: 1.) a hollow buoyant duck positioned in the path of <span class="hlt">waves</span> including a core about the center axis of which the duck <span class="hlt">rotates</span>, a lower chamber portion having liquid therein and an upper chamber portion having air therein. The air is alternately compressed and expanded by the liquid in the chamber during the <span class="hlt">rotational</span> motion of the duck caused by <span class="hlt">waves</span>. A turbine mounted in the upper portion of the duck is driven by the compressed and expanded air. A generator is coupled to the turbinemore » and operated to produce electrical energy and an air bulb; 2.) a spine having a transverse axial shaft anchoring the spine to the ocean floor. The upper portion of the spine engages the duck to maintain the duck in position. The spine has a curved configuration to concentrate and direct <span class="hlt">wave</span> energy. The spine configuration acts as a scoop to increase the height of <span class="hlt">wave</span> peaks and as a foil to increase the depth of <span class="hlt">wave</span> troughs.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EJPh...38c4010B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EJPh...38c4010B"><span><span class="hlt">Waves</span> and rays in plano-concave laser cavities: I. Geometric modes in the paraxial <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barré, N.; Romanelli, M.; Lebental, M.; Brunel, M.</p> <p>2017-05-01</p> <p>Eigenmodes of laser cavities are studied theoretically and experimentally in two companion papers, with the aim of making connections between undulatory and geometric properties of light. In this first paper, we focus on macroscopic open-cavity lasers with localized gain. The model is based on the <span class="hlt">wave</span> equation in the paraxial <span class="hlt">approximation</span>; experiments are conducted with a simple diode-pumped Nd:YAG laser with a variable cavity length. After recalling fundamentals of laser beam optics, we consider plano-concave cavities with on-axis or off-axis pumping, with emphasis put on degenerate cavity lengths, where modes of different order resonate at the same frequency, and combine to form surprising transverse beam profiles. Degeneracy leads to the oscillation of so-called geometric modes whose properties can be understood, to a certain extent, also within a ray optics picture. We first provide a heuristic description of these modes, based on geometric reasoning, and then show more rigorously how to derive them analytically by building <span class="hlt">wave</span> superpositions, within the framework of paraxial <span class="hlt">wave</span> optics. The numerical methods, based on the Fox-Li approach, are described in detail. The experimental setup, including the imaging system, is also detailed and relatively simple to reproduce. The aim is to facilitate implementation of both the numerics and of the experiments, and to show that one can have access not only to the common higher-order modes but also to more exotic patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910049S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910049S"><span>On the potential of seismic <span class="hlt">rotational</span> motion measurements for extraterrestrial seismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmelzbach, Cedric; Sollberger, David; Khan, Amir; Greenhalgh, Stewart; Van Renterghem, Cederic; Robertsson, Johan</p> <p>2017-04-01</p> <p>Classically, seismological recordings consist of measurements of translational ground motion only. However, in addition to three vector components of translation there are three components of <span class="hlt">rotation</span> to consider, leading to six degrees of freedom. Of particular interest is thereby the fact that measuring <span class="hlt">rotational</span> motion means isolating shear (S) <span class="hlt">waves</span>. Recording the <span class="hlt">rotational</span> motion requires dedicated <span class="hlt">rotational</span> sensors. Alternatively, since the <span class="hlt">rotational</span> motion is given by the curl of the vectorial displacements, the <span class="hlt">rotational</span> motion around the two horizontal axes can be computed from the horizontal spatial gradients of vertical translational recordings if standard translational seismometers are placed in an areal array at the free surface. This follows from the zero stress free surface condition. Combining <span class="hlt">rotational</span> and translational motion measurements opens up new ways of analyzing seismic data, such as facilitating much improved arrival identification and wavefield separation (e.g., P-/S-<span class="hlt">wave</span> separation), and local slowness (arrival direction and velocity) determination. Such combined measurements maximize the seismic information content that a single six-component station or a small station array can provide, and are of particular interest for sparse or single-station measurements such as in extraterrestrial seismology. We demonstrate the value of the analysis of combined translational and <span class="hlt">rotational</span> recordings by re-evaluating data from the Apollo 17 lunar seismic profiling experiment (LSPE). The LSPE setup consisted of four vertical-component geophones arranged in a star-like geometry. This areal receiver layout enables computing the horizontal spatial gradients by spatial finite differencing of the vertical-component data for two perpendicular directions and, hence, the estimation of <span class="hlt">rotational</span> motion around two horizontal axes. Specifically, the recorded seismic waveform data originated from eight explosive packages as well as from continuously</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24448425','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24448425"><span><span class="hlt">Rotational</span> spectroscopy with an optical centrifuge.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Korobenko, Aleksey; Milner, Alexander A; Hepburn, John W; Milner, Valery</p> <p>2014-03-07</p> <p>We demonstrate a new spectroscopic method for studying electronic transitions in molecules with extremely broad range of angular momentum. We employ an optical centrifuge to create narrow <span class="hlt">rotational</span> <span class="hlt">wave</span> packets in the ground electronic state of (16)O2. Using the technique of resonance-enhanced multi-photon ionization, we record the spectrum of multiple ro-vibrational transitions between X(3)Σg(-) and C(3)Πg electronic manifolds of oxygen. Direct control of <span class="hlt">rotational</span> excitation, extending to <span class="hlt">rotational</span> quantum numbers as high as N ≳ 120, enables us to interpret the complex structure of <span class="hlt">rotational</span> spectra of C(3)Πg beyond thermally accessible levels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S11D4366W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S11D4366W"><span>Development of a Single Station 6C-Approach for Array Analysis and Microzonation: Using Vertical <span class="hlt">Rotation</span> Rate to Estimate Love-<span class="hlt">Wave</span> Disperion Curves and Direction Finding</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wassermann, J. M.; Wietek, A.; Hadziioannou, C.; Igel, H.</p> <p>2014-12-01</p> <p>Microzonation, i.e. the estimation of (shear) <span class="hlt">wave</span> velocity profiles of the upper few 100m in dense 2D surface grids is one of the key methods to understand the variation in seismic hazard caused by ground shaking events. In this presentation we introduce a novel method for estimating the Love-<span class="hlt">wave</span> phase velocity dispersion by using ambient noise recordings. We use the vertical component of <span class="hlt">rotational</span> motions inherently present in ambient noise and the well established relation to simultaneous recordings of transverse acceleration. In this relation the frequency dependent phase velocity of a plane SH (or Love)-type <span class="hlt">wave</span> acts as a proportionality factor between the anti-correlated amplitudes of both measures. In a first step we used synthetic data sets with increasing complexity to evaluate the proposed technique and the developed algorithm to extract the direction and amplitude of the incoming ambient noise wavefield measured at a single site. Since reliable weak <span class="hlt">rotational</span> motion sensors are not yet readily available, we apply array derived <span class="hlt">rotation</span> measurements in order to test our method. We next use the technique to analyze different real data sets of ambient noise measurements as well as seismic recordings at active volcanoes and compare these results with findings of the Spatial AutoCorrelation technique which was applied to the same data set. We demonstrate that the newly developed technique shows comparable results to more classical, strictly array based methods. Furthermore, we show that as soon as portable weak motion <span class="hlt">rotational</span> motion sensors are available, a single 6C-station approach will be feasible, not only for microzonation but also for general array applications, with performance comparable to more classical techniques. An important advantage, especially in urban environments, is that with this approach, the number of seismic stations needed is drastically reduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900002973','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900002973"><span>Acoustic controlled <span class="hlt">rotation</span> and orientation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barmatz, Martin B. (Inventor); Allen, James L. (Inventor)</p> <p>1989-01-01</p> <p>Acoustic energy is applied to a pair of locations spaced about a chamber, to control <span class="hlt">rotation</span> of an object levitated in the chamber. Two acoustic transducers applying energy of a single acoustic mode, one at each location, can (one or both) serve to levitate the object in three dimensions as well as control its <span class="hlt">rotation</span>. Slow <span class="hlt">rotation</span> is achieved by initially establishing a large phase difference and/or pressure ratio of the acoustic <span class="hlt">waves</span>, which is sufficient to turn the object by more than 45 deg, which is immediately followed by reducing the phase difference and/or pressure ratio to maintain slow <span class="hlt">rotation</span>. A small phase difference and/or pressure ratio enables control of the angular orientation of the object without <span class="hlt">rotating</span> it. The sphericity of an object can be measured by its response to the acoustic energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S21A0694S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S21A0694S"><span>Applications of seismic spatial wavefield gradient and <span class="hlt">rotation</span> data in exploration seismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmelzbach, C.; Van Renterghem, C.; Sollberger, D.; Häusler, M.; Robertsson, J. O. A.</p> <p>2017-12-01</p> <p>Seismic spatial wavefield gradient and <span class="hlt">rotation</span> data have the potential to open up new ways to address long-standing problems in land-seismic exploration such as identifying and separating P-, S-, and surface <span class="hlt">waves</span>. Gradient-based acquisition and processing techniques could enable replacing large arrays of densely spaced receivers by sparse spatially-compact receiver layouts or even one single multicomponent station with dedicated instruments (e.g., <span class="hlt">rotational</span> seismometers). Such approaches to maximize the information content of single-station recordings are also of significant interest for seismic measurements at sites with limited access such as boreholes, the sea bottom, and extraterrestrial seismology. Arrays of conventional three-component (3C) geophones enable measuring not only the particle velocity in three dimensions but also estimating their spatial gradients. Because the free-surface condition allows to express vertical derivatives in terms of horizontal derivatives, the full gradient tensor and, hence, curl and divergence of the wavefield can be computed. In total, three particle velocity components, three <span class="hlt">rotational</span> components, and divergence, result seven-component (7C) seismic data. Combined particle velocity and gradient data can be used to isolate the incident P- or S-<span class="hlt">waves</span> at the land surface or the sea bottom using filtering techniques based on the elastodynamic representation theorem. Alternatively, as only S-<span class="hlt">waves</span> exhibit <span class="hlt">rotational</span> motion, <span class="hlt">rotational</span> measurements can directly be used to identify S-<span class="hlt">waves</span>. We discuss the derivations of the gradient-based filters as well as their application to synthetic and field data, demonstrating that <span class="hlt">rotational</span> data can be of particular interest to S-<span class="hlt">wave</span> reflection and P-to-S-<span class="hlt">wave</span> conversion imaging. The concept of array-derived gradient estimation can be extended to source arrays as well. Therefore, source arrays allow us to emulate <span class="hlt">rotational</span> (curl) and dilatational (divergence) sources. Combined with 7C</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19506639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19506639"><span>Harmonic generation beyond the Strong-Field <span class="hlt">Approximation</span>: the physics behind the short-<span class="hlt">wave</span>-infrared scaling laws.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pérez-Hernández, J A; Roso, L; Plaja, L</p> <p>2009-06-08</p> <p>The physics of laser-mater interactions beyond the perturbative limit configures the field of extreme non-linear optics. Although most experiments have been done in the near infrared ( lambda <or= 1 microm), the situation is changing nowadays with the development of sources at longer wavelengths (<5 microm), opening new perspectives in the synthesis of shorter XUV attosecond pulses and higher frequencies. The theory of intense-field interactions is based either on the exact numerical integration of the time-dependent Schrödinger equation or in the development of models, mostly based on the strong-field <span class="hlt">approximation</span>. Recent studies in the short-<span class="hlt">wave</span> infrared show a divergence between the predictions of these models and the exact results. In this paper we will show that this discrepancy reveals the incompleteness of our present understanding of high-order harmonic generation. We discuss the physical grounds, provide a theoretical framework beyond the standard <span class="hlt">approximations</span> and develop a compact approach that accounts for the correct scaling of the harmonic yield.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29092514','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29092514"><span>A large-diameter hollow-shaft cryogenic motor based on a superconducting magnetic bearing for millimeter-<span class="hlt">wave</span> polarimetry.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Johnson, B R; Columbro, F; Araujo, D; Limon, M; Smiley, B; Jones, G; Reichborn-Kjennerud, B; Miller, A; Gupta, S</p> <p>2017-10-01</p> <p>In this paper, we present the design and measured performance of a novel cryogenic motor based on a superconducting magnetic bearing (SMB). The motor is tailored for use in millimeter-<span class="hlt">wave</span> half-<span class="hlt">wave</span> plate (HWP) polarimeters, where a HWP is rapidly <span class="hlt">rotated</span> in front of a polarization analyzer or polarization-sensitive detector. This polarimetry technique is commonly used in cosmic microwave background polarization studies. The SMB we use is composed of fourteen yttrium barium copper oxide (YBCO) disks and a contiguous neodymium iron boron (NdFeB) ring magnet. The motor is a hollow-shaft motor because the HWP is ultimately installed in the rotor. The motor presented here has a 100 mm diameter rotor aperture. However, the design can be scaled up to rotor aperture diameters of <span class="hlt">approximately</span> 500 mm. Our motor system is composed of four primary subsystems: (i) the rotor assembly, which includes the NdFeB ring magnet, (ii) the stator assembly, which includes the YBCO disks, (iii) an incremental encoder, and (iv) the drive electronics. While the YBCO is cooling through its superconducting transition, the rotor is held above the stator by a novel hold and release mechanism. The encoder subsystem consists of a custom-built encoder disk read out by two fiber optic readout sensors. For the demonstration described in this paper, we ran the motor at 50 K and tested <span class="hlt">rotation</span> frequencies up to <span class="hlt">approximately</span> 10 Hz. The feedback system was able to stabilize the <span class="hlt">rotation</span> speed to <span class="hlt">approximately</span> 0.4%, and the measured rotor orientation angle uncertainty is less than 0.15°. Lower temperature operation will require additional development activities, which we will discuss.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017RScI...88j5102J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017RScI...88j5102J"><span>A large-diameter hollow-shaft cryogenic motor based on a superconducting magnetic bearing for millimeter-<span class="hlt">wave</span> polarimetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, B. R.; Columbro, F.; Araujo, D.; Limon, M.; Smiley, B.; Jones, G.; Reichborn-Kjennerud, B.; Miller, A.; Gupta, S.</p> <p>2017-10-01</p> <p>In this paper, we present the design and measured performance of a novel cryogenic motor based on a superconducting magnetic bearing (SMB). The motor is tailored for use in millimeter-<span class="hlt">wave</span> half-<span class="hlt">wave</span> plate (HWP) polarimeters, where a HWP is rapidly <span class="hlt">rotated</span> in front of a polarization analyzer or polarization-sensitive detector. This polarimetry technique is commonly used in cosmic microwave background polarization studies. The SMB we use is composed of fourteen yttrium barium copper oxide (YBCO) disks and a contiguous neodymium iron boron (NdFeB) ring magnet. The motor is a hollow-shaft motor because the HWP is ultimately installed in the rotor. The motor presented here has a 100 mm diameter rotor aperture. However, the design can be scaled up to rotor aperture diameters of <span class="hlt">approximately</span> 500 mm. Our motor system is composed of four primary subsystems: (i) the rotor assembly, which includes the NdFeB ring magnet, (ii) the stator assembly, which includes the YBCO disks, (iii) an incremental encoder, and (iv) the drive electronics. While the YBCO is cooling through its superconducting transition, the rotor is held above the stator by a novel hold and release mechanism. The encoder subsystem consists of a custom-built encoder disk read out by two fiber optic readout sensors. For the demonstration described in this paper, we ran the motor at 50 K and tested <span class="hlt">rotation</span> frequencies up to <span class="hlt">approximately</span> 10 Hz. The feedback system was able to stabilize the <span class="hlt">rotation</span> speed to <span class="hlt">approximately</span> 0.4%, and the measured rotor orientation angle uncertainty is less than 0.15°. Lower temperature operation will require additional development activities, which we will discuss.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989JChPh..90.4835N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989JChPh..90.4835N"><span>Theory of <span class="hlt">rotational</span> transition in atom-diatom chemical reaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakamura, Masato; Nakamura, Hiroki</p> <p>1989-05-01</p> <p><span class="hlt">Rotational</span> transition in atom-diatom chemical reaction is theoretically studied. A new <span class="hlt">approximate</span> theory (which we call IOS-DW <span class="hlt">approximation</span>) is proposed on the basis of the physical idea that <span class="hlt">rotational</span> transition in reaction is induced by the following two different mechanisms: <span class="hlt">rotationally</span> inelastic half collision in both initial and final arrangement channels, and coordinate transformation in the reaction zone. This theory gives a fairy compact expression for the state-to-state transition probability. Introducing the additional physically reasonable assumption that reaction (particle rearrangement) takes place in a spatially localized region, we have reduced this expression into a simpler analytical form which can explicitly give overall <span class="hlt">rotational</span> state distribution in reaction. Numerical application was made to the H+H2 reaction and demonstrated its effectiveness for the simplicity. A further simplified most naive <span class="hlt">approximation</span>, i.e., independent events <span class="hlt">approximation</span> was also proposed and demonstrated to work well in the test calculation of H+H2. The overall <span class="hlt">rotational</span> state distribution is expressed simply by a product sum of the transition probabilities for the three consecutive processes in reaction: inelastic transition in the initial half collision, transition due to particle rearrangement, and inelastic transition in the final half collision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA195316','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA195316"><span><span class="hlt">Approximate</span> Upper Limit of Irregular <span class="hlt">Wave</span> Runup on Riprap.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1988-05-01</p> <p>MAR 8" P editon ’ayb e used utlI exhausteo SC.A’ (ASS,4CA’ON 01_’- S PA(E_ All other ed,t,os are obsolete Unclassified ;I . % ", .. , r .,., . ,C_...Manager, CERC, and Mr. C. E . Chatham, Jr., Chief, <span class="hlt">Wave</span> Dynamics Division, CERC. COL Dwayne G. Lee, CE, was Commander and Director of WES during the 0...prevent exceedance by runup or to estimate the potential severity of <span class="hlt">wave</span> overtopping. e PART II: SOURCES OF DATA, TEST SETUPS, AND A. TEST CONDITIONS 3</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22483143-controlling-plasmonic-surface-waves-metallic-nanowires-transformation-optics','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22483143-controlling-plasmonic-surface-waves-metallic-nanowires-transformation-optics"><span>Controlling the plasmonic surface <span class="hlt">waves</span> of metallic nanowires by transformation optics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Liu, Yichao; Yuan, Jun; Yin, Ge</p> <p>2015-07-06</p> <p>In this letter, we introduce the technique of using transformation optics to manipulate the mode states of surface plasmonic <span class="hlt">waves</span> of metallic nanowire waveguides. As examples we apply this technique to design two optical components: a three-dimensional (3D) electromagnetic mode <span class="hlt">rotator</span> and a mode convertor. The <span class="hlt">rotator</span> can <span class="hlt">rotate</span> the polarization state of the surface <span class="hlt">wave</span> around plasmonic nanowires by arbitrarily desired angles, and the convertor can transform the surface <span class="hlt">wave</span> modes from one to another. Full-<span class="hlt">wave</span> simulation is performed to verify the design and efficiency of our devices. Their potential application in photonic circuits is envisioned.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6127..355O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6127..355O"><span>High-sensitivity <span class="hlt">rotation</span> sensing with atom interferometers using Aharonov-Bohm effect</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Özcan, Meriac</p> <p>2006-02-01</p> <p>In recent years there has been significant activity in research and development of high sensitivity accelerometers and gyroscopes using atom interferometers. In these devices, a fringe shift in the interference of atom de Broglie <span class="hlt">waves</span> indicates the <span class="hlt">rotation</span> rate of the interferometer relative to an inertial frame of reference. In both optical and atomic conventional Sagnac interferometers, the resultant phase difference due to <span class="hlt">rotation</span> is independent of the <span class="hlt">wave</span> velocity. However, we show that if an atom interforemeter is enclosed in a Faraday cage which is at some potential, the phase difference of the counter-propagating <span class="hlt">waves</span> is proportional to the inverse square of the particle velocity and it is proportional to the applied potential. This is due to Aharonov-Bohm effect and it can be used to increase the <span class="hlt">rotation</span> sensitivity of atom interferometers.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvF...2c3801R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvF...2c3801R"><span>Segregation of helicity in inertial <span class="hlt">wave</span> packets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ranjan, A.</p> <p>2017-03-01</p> <p>Inertial <span class="hlt">waves</span> are known to exist in the Earth's rapidly <span class="hlt">rotating</span> outer core and could be important for the dynamo generation. It is well known that a monochromatic inertial plane <span class="hlt">wave</span> traveling parallel to the <span class="hlt">rotation</span> axis (along positive z ) has negative helicity while the <span class="hlt">wave</span> traveling antiparallel (negative z ) has positive helicity. Such a helicity segregation, north and south of the equator, is necessary for the α2-dynamo model based on inertial <span class="hlt">waves</span> [Davidson, Geophys. J. Int. 198, 1832 (2014), 10.1093/gji/ggu220] to work. The core is likely to contain a myriad of inertial <span class="hlt">waves</span> of different <span class="hlt">wave</span> numbers and frequencies. In this study, we investigate whether this characteristic of helicity segregation also holds for an inertial <span class="hlt">wave</span> packet comprising <span class="hlt">waves</span> with the same sign of Cg ,z, the z component of group velocity. We first derive the polarization relations for inertial <span class="hlt">waves</span> and subsequently derive the resultant helicity in <span class="hlt">wave</span> packets forming as a result of superposition of two or more <span class="hlt">waves</span>. We find that the helicity segregation does hold for an inertial <span class="hlt">wave</span> packet unless the <span class="hlt">wave</span> numbers of the constituent <span class="hlt">waves</span> are widely separated. In the latter case, regions of opposite color helicity do appear, but the mean helicity retains the expected sign. An illustration of this observation is provided by (a) calculating the resultant helicity for a <span class="hlt">wave</span> packet formed by superposition of four upward-propagating inertial <span class="hlt">waves</span> with different <span class="hlt">wave</span> vectors and (b) conducting the direct numerical simulation of a Gaussian eddy under rapid <span class="hlt">rotation</span>. Last, the possible effects of other forces such as the viscous dissipation, the Lorentz force, buoyancy stratification, and nonlinearity on helicity are investigated and discussed. The helical structure of the <span class="hlt">wave</span> packet is likely to remain unaffected by dissipation or the magnetic field, but can be modified by the presence of linearly stable stratification and nonlinearity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020078405','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020078405"><span>Gravitational <span class="hlt">Waves</span> from <span class="hlt">Rotating</span> Neutron Stars and Evaluation of fast Chirp Transform Techniques</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Strohmayer, Tod E.; White, Nicholas E. (Technical Monitor)</p> <p>2000-01-01</p> <p>X-ray observations suggest that neutron stars in low mass X-ray binaries (LMXB) are <span class="hlt">rotating</span> with frequencies from 300 - 600 Hz. These spin rates are significantly less than the break-up rates for essentially all realistic neutron star equations of state, suggesting that some process may limit the spin frequencies of accreting neutron stars to this range. If the accretion induced spin up torque is in equilibrium with gravitational radiation losses, these objects could be interesting sources of gravitational <span class="hlt">waves</span>. I present a brief summary of current measurements of neutron star spins in LMXBs based on the observations of high-Q oscillations during thermonuclear bursts (so called 'burst oscillations'). Further measurements of neutron star spins will be important in exploring the gravitational radiation hypothesis in more detail. To this end I also present a study of fast chirp transform (FCT) techniques as described by Jenet and Prince in the context of searching for the chirping signals observed during X-ray bursts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2748696','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2748696"><span>Origin choice and petal loss in the flower garden of spiral <span class="hlt">wave</span> tip trajectories</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gray, Richard A.; Wikswo, John P.; Otani, Niels F.</p> <p>2009-01-01</p> <p><span class="hlt">Rotating</span> spiral <span class="hlt">waves</span> have been observed in numerous biological and physical systems. These spiral <span class="hlt">waves</span> can be stationary, meander, or even degenerate into multiple unstable <span class="hlt">rotating</span> <span class="hlt">waves</span>. The spatiotemporal behavior of spiral <span class="hlt">waves</span> has been extensively quantified by tracking spiral <span class="hlt">wave</span> tip trajectories. However, the precise methodology of identifying the spiral <span class="hlt">wave</span> tip and its influence on the specific patterns of behavior remains a largely unexplored topic of research. Here we use a two-state variable FitzHugh–Nagumo model to simulate stationary and meandering spiral <span class="hlt">waves</span> and examine the spatiotemporal representation of the system’s state variables in both the real (i.e., physical) and state spaces. We show that mapping between these two spaces provides a method to demarcate the spiral <span class="hlt">wave</span> tip as the center of <span class="hlt">rotation</span> of the solution to the underlying nonlinear partial differential equations. This approach leads to the simplest tip trajectories by eliminating portions resulting from the <span class="hlt">rotational</span> component of the spiral <span class="hlt">wave</span>. PMID:19791998</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19791998','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19791998"><span>Origin choice and petal loss in the flower garden of spiral <span class="hlt">wave</span> tip trajectories.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gray, Richard A; Wikswo, John P; Otani, Niels F</p> <p>2009-09-01</p> <p><span class="hlt">Rotating</span> spiral <span class="hlt">waves</span> have been observed in numerous biological and physical systems. These spiral <span class="hlt">waves</span> can be stationary, meander, or even degenerate into multiple unstable <span class="hlt">rotating</span> <span class="hlt">waves</span>. The spatiotemporal behavior of spiral <span class="hlt">waves</span> has been extensively quantified by tracking spiral <span class="hlt">wave</span> tip trajectories. However, the precise methodology of identifying the spiral <span class="hlt">wave</span> tip and its influence on the specific patterns of behavior remains a largely unexplored topic of research. Here we use a two-state variable FitzHugh-Nagumo model to simulate stationary and meandering spiral <span class="hlt">waves</span> and examine the spatiotemporal representation of the system's state variables in both the real (i.e., physical) and state spaces. We show that mapping between these two spaces provides a method to demarcate the spiral <span class="hlt">wave</span> tip as the center of <span class="hlt">rotation</span> of the solution to the underlying nonlinear partial differential equations. This approach leads to the simplest tip trajectories by eliminating portions resulting from the <span class="hlt">rotational</span> component of the spiral <span class="hlt">wave</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JMoSp.182..148A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JMoSp.182..148A"><span><span class="hlt">Rotational</span> Spectrum and Internal <span class="hlt">Rotation</span> Barrier of 1-Chloro-1,1-difluoroethane</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alonso, José L.; López, Juan C.; Blanco, Susana; Guarnieri, Antonio</p> <p>1997-03-01</p> <p>The <span class="hlt">rotational</span> spectra of 1-chloro-1,1-difluoroethane (HCFC-142b) has been investigated in the frequency region 8-115 GHz with Stark, waveguide Fourier transform (FTMW), and millimeter-<span class="hlt">wave</span> spectrometers. Assignments in large frequency regions with the corresponding frequency measurements have been made for the ground andv18= 1 (CH3torsion) vibrational states of the35Cl isotopomer and for the ground state of the37Cl species. Accurate <span class="hlt">rotational</span>, quartic centrifugal distortion, and quadrupole coupling constants have been determined from global fits considering all these states. SmallA-Einternal <span class="hlt">rotation</span> splittings have been observed for thev18= 1 vibrational state using FTMW spectroscopy. The barrier height for the internal <span class="hlt">rotation</span> of the methyl group has been determined to be 3751 (4) cal mol-1, in disagreement with the previous microwave value of 4400 (100) cal mol-1reported by G. Graner and C. Thomas [J. Chem. Phys.49,4160-4167 (1968)].</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1330358','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1330358"><span>Advances in <span class="hlt">Rotational</span> Seismic Measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Pierson, Robert; Laughlin, Darren; Brune, Robert</p> <p>2016-10-19</p> <p><span class="hlt">Rotational</span> motion is increasingly understood to be a significant part of seismic <span class="hlt">wave</span> motion. <span class="hlt">Rotations</span> can be important in earthquake strong motion and in Induced Seismicity Monitoring. <span class="hlt">Rotational</span> seismic data can also enable shear selectivity and improve wavefield sampling for vertical geophones in 3D surveys, among other applications. However, sensor technology has been a limiting factor to date. The US Department of Energy (DOE) and Applied Technology Associates (ATA) are funding a multi-year project that is now entering Phase 2 to develop and deploy a new generation of <span class="hlt">rotational</span> sensors for validation of <span class="hlt">rotational</span> seismic applications. Initial focus is onmore » induced seismicity monitoring, particularly for Enhanced Geothermal Systems (EGS) with fracturing. The sensors employ Magnetohydrodynamic (MHD) principles with broadband response, improved noise floors, robustness, and repeatability. This paper presents a summary of Phase 1 results and Phase 2 status.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993ppcn.conf..375S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993ppcn.conf..375S"><span>Generation and maintenance of bisymmetric spiral magnetic fields in disk galaxies in differential <span class="hlt">rotation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sawa, Takeyasu; Fujimoto, M.</p> <p>1993-05-01</p> <p>The <span class="hlt">approximate</span> dynamo equation, which yields asymptotic solutions for the large scale bisymmetric spiral (BSS) magnetic fields <span class="hlt">rotating</span> rigidly over a large area of the galactic disk, is derived. The vertical thickness and the dynamo strength of the gaseous disk which are necessary to generate and sustain the BSS magnetic fields is determined. The globally BSS magnetic fields which propagate over the disk as a <span class="hlt">wave</span> without being twisted more tightly are reproduced. A poloidal field configuration is theoretically predicted in the halo around the disk, and is observed in the edge-on galaxy NGC4631. Mathematical methods for the galactic dynamo are shown to be equivalent. Those methods give different growth rates between the BSS and the axisymmetric spiral (ASS) magnetic fields in the disk. Magnetohydrodynamical excitation is discussed between the BSS magnetic fields and the two armed spiral density <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Geomo.304..141S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Geomo.304..141S"><span>A life-cycle model for <span class="hlt">wave</span>-dominated tidal inlets along passive margin coasts of North America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seminack, Christopher T.; McBride, Randolph A.</p> <p>2018-03-01</p> <p>A regional overview of 107 <span class="hlt">wave</span>-dominated tidal inlets along the U.S. Atlantic coast, U.S. Gulf of Mexico coast, and Canadian Gulf of St. Lawrence coast yielded a generalized <span class="hlt">wave</span>-dominated tidal inlet life-cycle model that recognized the <span class="hlt">rotational</span> nature of tidal inlets. Tidal inlets are influenced by concurrently acting processes transpiring over two timescales: short-term, event-driven processes and long-term, evolutionary processes. <span class="hlt">Wave</span>-dominated tidal inlets are classified into three <span class="hlt">rotational</span> categories based on net longshore sediment transport direction and <span class="hlt">rotation</span> direction along the landward (back-barrier) portion of the inlet channel: downdrift channel <span class="hlt">rotation</span>, updrift channel <span class="hlt">rotation</span>, or little-to-no channel <span class="hlt">rotation</span>. Lateral shifting of the flood-tidal delta depocenter in response to available estuarine accommodation space appears to control inlet channel <span class="hlt">rotation</span>. Flood-tidal delta deposits fill accommodation space locally within the estuary (i.e., creating bathymetric highs), causing the tidal-inlet channel to <span class="hlt">rotate</span>. External influences, such as fluvial discharge, pre-existing back-barrier channels, and impeding salt marsh will also influence inlet-channel <span class="hlt">rotation</span>. Storm events may rejuvenate the tidal inlet by scouring sediment within the flood-tidal delta, increasing local accommodation space. <span class="hlt">Wave</span>-dominated tidal inlets are generally unstable and tend to open, concurrently migrate laterally and <span class="hlt">rotate</span>, infill, and close. Channel <span class="hlt">rotation</span> is a primary reason for <span class="hlt">wave</span>-dominated tidal inlet closure. During <span class="hlt">rotation</span>, the inlet channel lengthens and hydraulic efficiency decreases, thus causing tidal prism to decrease. Tidal prism, estuarine accommodation space, and sediment supply to the flood-tidal delta are the primary variables responsible for tidal inlet <span class="hlt">rotation</span>. Stability of <span class="hlt">wave</span>-dominated tidal inlets is further explained by: stability (S) = tidal prism (Ω) + estuarine accommodation space (V) - volume of annual sediment supply (Mt</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830056111&hterms=Solar+system+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSolar%2Bsystem%2Bfacts','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830056111&hterms=Solar+system+facts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSolar%2Bsystem%2Bfacts"><span>On the large-scale dynamics of rapidly <span class="hlt">rotating</span> convection zones. [in solar and stellar interiors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Durney, B. R.</p> <p>1983-01-01</p> <p>The fact that the values of the eight basic <span class="hlt">waves</span> present in turbulent flows in the presence of <span class="hlt">rotation</span> prohibit a tilt of eddy towards the axis of <span class="hlt">rotation</span> is incorporated into a formalism for rapidly <span class="hlt">rotating</span> convection zones. Equations for turbulent velocities are defined in a <span class="hlt">rotating</span> coordinate system, assuming that gravity and grad delta T act in a radial direction. An expression is derived for the lifetime of a basic <span class="hlt">wave</span> and then for the average velocity vector. A real convective eddy is formulated and the <span class="hlt">wave</span> vectors are calculated. The velocity amplitude and the stress tensor amplitude are integrated over the eddy domain. Applied to the solar convective zone, it is found that the convective cells are aligned along the axis of <span class="hlt">rotation</span> at the poles and at the equator, a model that conflicts with nonrotating mixng length theory predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880066978&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcentrifugal%2Bcompressor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880066978&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcentrifugal%2Bcompressor"><span>Weak <span class="hlt">rotating</span> flow disturbances in a centrifugal compressor with a vaneless diffuser</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Moore, F. K.</p> <p>1988-01-01</p> <p>A theory is presented to predict the occurrence of weak <span class="hlt">rotating</span> <span class="hlt">waves</span> in a centrifugal compression system with a vaneless diffuser. As in a previous study of axial systems, an undisturbed performance characteristic is assumed known. Following an inviscid analysis of the diffuser flow, conditions for a neutral <span class="hlt">rotating</span> disturbance are found. The solution is shown to have two branches; one with fast <span class="hlt">rotation</span>, the other with very slow <span class="hlt">rotation</span>. The slow branch includes a dense set of resonant solutions. The resonance is a feature of the diffuser flow, and therefore such disturbances must be expected at the various resonant flow coefficients regardless of the compressor characteristic. Slow solutions seem limited to flow coefficients less than about 0.3, where third and fourth harmonics appear. Fast <span class="hlt">waves</span> seem limited to a first harmonic. These fast and slow <span class="hlt">waves</span> are described, and effects of diffuser-wall convergence, backward blade angles, and partial recovery of exit velocity head are assessed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24593374','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24593374"><span>Modulation of cosmic microwave background polarization with a warm rapidly <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate on the Atacama B-Mode Search instrument.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kusaka, A; Essinger-Hileman, T; Appel, J W; Gallardo, P; Irwin, K D; Jarosik, N; Nolta, M R; Page, L A; Parker, L P; Raghunathan, S; Sievers, J L; Simon, S M; Staggs, S T; Visnjic, K</p> <p>2014-02-01</p> <p>We evaluate the modulation of cosmic microwave background polarization using a rapidly <span class="hlt">rotating</span>, half-<span class="hlt">wave</span> plate (HWP) on the Atacama B-Mode Search. After demodulating the time-ordered-data (TOD), we find a significant reduction of atmospheric fluctuations. The demodulated TOD is stable on time scales of 500-1000 s, corresponding to frequencies of 1-2 mHz. This facilitates recovery of cosmological information at large angular scales, which are typically available only from balloon-borne or satellite experiments. This technique also achieves a sensitive measurement of celestial polarization without differencing the TOD of paired detectors sensitive to two orthogonal linear polarizations. This is the first demonstration of the ability to remove atmospheric contamination at these levels from a ground-based platform using a rapidly <span class="hlt">rotating</span> HWP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AcAau.140..388S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AcAau.140..388S"><span>Effects of injection nozzle exit width on <span class="hlt">rotating</span> detonation engine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Jian; Zhou, Jin; Liu, Shijie; Lin, Zhiyong; Cai, Jianhua</p> <p>2017-11-01</p> <p>A series of numerical simulations of RDE modeling real injection nozzles with different exit widths are performed in this paper. The effects of nozzle exit width on chamber inlet state, plenum flowfield and detonation propagation are analyzed. The results are compared with that using an ideal injection model. Although the ideal injection model is a good <span class="hlt">approximation</span> method to model RDE inlet, the two-dimensional effects of real nozzles are ignored in the ideal injection model so that some complicated phenomena such as the reflected <span class="hlt">waves</span> caused by the nozzle walls and the reversed flow into the nozzles can not be modeled accurately. Additionally, the ideal injection model overpredicts the block ratio. In all the cases that stabilize at one-<span class="hlt">wave</span> mode, the block ratio increases as the nozzle exit width gets smaller. The dual-<span class="hlt">wave</span> mode case also has a relatively high block ratio. A pressure oscillation in the plenum with the same main frequency with the <span class="hlt">rotating</span> detonation <span class="hlt">wave</span> is observed. A parameter σ is applied to describe the non-uniformity in the plenum. σ increases as the nozzle exit width gets larger. Under some condition, the heat release on the interface of fresh premixed gas layer and detonation products can be strong enough to induce a new detonation <span class="hlt">wave</span>. A spontaneous mode-transition process is observed for the smallest exit width case. Due to the detonation products existing in the premixed gas layer before the detonation <span class="hlt">wave</span>, the detonation <span class="hlt">wave</span> will propagate through reactants and products alternately, and therefore its strength will vary with time, especially near the chamber inlet. This tendency gets weaker as the injection nozzle exit width increases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22617137-possible-acceleration-cosmic-rays-rotating-system-uehling-uhlenbeck-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22617137-possible-acceleration-cosmic-rays-rotating-system-uehling-uhlenbeck-model"><span>Possible acceleration of cosmic rays in a <span class="hlt">rotating</span> system: Uehling-Uhlenbeck model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kwang-Hua, Chu Rainer, E-mail: 1559877413@qq.com</p> <p>2016-11-15</p> <p>We illustrate the possible acceleration of cosmic rays passing through a kind of amplification channel (via diffusion modes of propagating plane-<span class="hlt">wave</span> fronts) induced by a <span class="hlt">rotating</span> system. Our analysis is mainly based on the quantum discrete kinetic model (considering a discrete Uehling-Uhlenbeck collision term), which has been used to study the propagation of plane (e.g., acoustic) <span class="hlt">waves</span> in a system of <span class="hlt">rotating</span> gases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.474.1644L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.474.1644L"><span>Tidal dissipation in <span class="hlt">rotating</span> fluid bodies: the presence of a magnetic field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Yufeng; Ogilvie, Gordon I.</p> <p>2018-02-01</p> <p>We investigate effects of the presence of a magnetic field on tidal dissipation in <span class="hlt">rotating</span> fluid bodies. We consider a simplified model consisting of a rigid core and a fluid envelope, permeated by a background magnetic field (either a dipolar field or a uniform axial field). The <span class="hlt">wave</span>-like tidal responses in the fluid layer are in the form of magnetic Coriolis <span class="hlt">waves</span>, which are restored by both the Coriolis force and the Lorentz force. Energy dissipation occurs through viscous damping and Ohmic damping of these <span class="hlt">waves</span>. Our numerical results show that the tidal dissipation can be dominated by Ohmic damping even with a weak magnetic field. The presence of a magnetic field smooths out the complicated frequency dependence of the dissipation rate, and broadens the frequency spectrum of the dissipation rate, depending on the strength of the background magnetic field. However, the frequency-averaged dissipation is independent of the strength and structure of the magnetic field, and of the dissipative parameters in the <span class="hlt">approximation</span> that the <span class="hlt">wave</span>-like response is driven only by the Coriolis force acting on the non-wavelike tidal flow. Indeed, the frequency-averaged dissipation quantity is in good agreement with previous analytical results in the absence of magnetic fields. Our results suggest that the frequency-averaged tidal dissipation of the <span class="hlt">wave</span>-like perturbations is insensitive to detailed damping mechanisms and dissipative properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10238E..1BB','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10238E..1BB"><span>An all-reflective polarization <span class="hlt">rotator</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bohus, J.; Budai, Judit; Kalashnikov, M.; Osvay, K.</p> <p>2017-05-01</p> <p>The conceptual design and proof of principle experimental results of a polarization <span class="hlt">rotator</span> based on mirrors are presented. The device is suitable for any-angle, online <span class="hlt">rotation</span> of the plane of polarization of high peak intensity ultrashort laser pulses. Controllable <span class="hlt">rotation</span> of the polarization vector of short laser pulses with a broad bandwidth requires achromatic retarding plates which have a limited scalability and the substantial plate thickness can lead to pulse broadening and inaccurate polarization <span class="hlt">rotation</span>. Polarization <span class="hlt">rotators</span> based on reflective optical elements are preferable alternatives to <span class="hlt">wave</span> plates especially when used in high average power or high peak intensity ultra-short laser systems. The control of the polarization state is desirable in many laser-matter interaction experiments e.g., high harmonic and attosecond pulse generation, electron, proton and ion acceleration, electron-positron pair creating, vacuum nonlinear polarization effect. The device can also serve as a beam attenuator, in combination with a linear polarizer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24580350','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24580350"><span>Localized transversal-<span class="hlt">rotational</span> modes in linear chains of equal masses.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pichard, H; Duclos, A; Groby, J-P; Tournat, V; Gusev, V E</p> <p>2014-01-01</p> <p>The propagation and localization of transversal-<span class="hlt">rotational</span> <span class="hlt">waves</span> in a two-dimensional granular chain of equal masses are analyzed in this study. The masses are infinitely long cylinders possessing one translational and one <span class="hlt">rotational</span> degree of freedom. Two dispersive propagating modes are predicted in this granular crystal. By considering the semi-infinite chain with a boundary condition applied at its beginning, the analytical study demonstrates the existence of localized modes, each mode composed of two evanescent modes. Their existence, position (either in the gap between the propagating modes or in the gap above the upper propagating mode), and structure of spatial localization are analyzed as a function of the relative strength of the shear and bending interparticle interactions and for different boundary conditions. This demonstrates the existence of a localized mode in a semi-infinite monatomic chain when transversal-<span class="hlt">rotational</span> <span class="hlt">waves</span> are considered, while it is well known that these types of modes do not exist when longitudinal <span class="hlt">waves</span> are considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001MNRAS.322..389Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001MNRAS.322..389Y"><span>Quasi-radial modes of <span class="hlt">rotating</span> stars in general relativity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoshida, Shin'ichirou; Eriguchi, Yoshiharu</p> <p>2001-04-01</p> <p>By using the Cowling <span class="hlt">approximation</span>, quasi-radial modes of <span class="hlt">rotating</span> general relativistic stars are computed along equilibrium sequences from non-<span class="hlt">rotating</span> to maximally <span class="hlt">rotating</span> models. The eigenfrequencies of these modes are decreasing functions of the <span class="hlt">rotational</span> frequency. The eigenfrequency curve of each mode as a function of the <span class="hlt">rotational</span> frequency has discontinuities, which arise from the avoided crossing with other curves of axisymmetric modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830052662&hterms=water+filters&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dwater%2Bfilters','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830052662&hterms=water+filters&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dwater%2Bfilters"><span>The effects of the Asselin time filter on numerical solutions to the linearized shallow-water <span class="hlt">wave</span> equations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schlesinger, R. E.; Johnson, D. R.; Uccellini, L. W.</p> <p>1983-01-01</p> <p>In the present investigation, a one-dimensional linearized analysis is used to determine the effect of Asselin's (1972) time filter on both the computational stability and phase error of numerical solutions for the shallow water <span class="hlt">wave</span> equations, in cases with diffusion but without <span class="hlt">rotation</span>. An attempt has been made to establish the <span class="hlt">approximate</span> optimal values of the filtering parameter nu for each of the 'lagged', Dufort-Frankel, and Crank-Nicholson diffusion schemes, suppressing the computational <span class="hlt">wave</span> mode without materially altering the physical <span class="hlt">wave</span> mode. It is determined that in the presence of diffusion, the optimum filter length depends on whether <span class="hlt">waves</span> are undergoing significant propagation. When moderate propagation is present, with or without diffusion, the Asselin filter has little effect on the spatial phase lag of the physical mode for the leapfrog advection scheme of the three diffusion schemes considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14679427','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14679427"><span>[Radial shock <span class="hlt">wave</span> therapy in calcifying tendinitis of the <span class="hlt">rotator</span> cuff--a prospective study].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Magosch, P; Lichtenberg, S; Habermeyer, P</p> <p>2003-01-01</p> <p>The aim of the study is to evaluate the influence of radial shock <span class="hlt">wave</span> therapy (RSWT) on the course of calcifying tendinitis of the <span class="hlt">rotator</span> cuff. 35 patients with a mean age of 47.5 years suffering from calcifying tendinitis stage Gaertner 2 with a mean size of 16.6 mm in typical location (true-ap view) for a mean of 28 months were treated by low-energy RSWT three times. The acromio-humeral distance averaged 10.4 mm measured at the true-ap view. All patients were clinically and radiologically followed-up at 4 weeks, 3, 6 and 12 months after the last treatment. The Constant score improved significantly (p < 0.0001) during the first 4 weeks after RSWT from a mean of 68.5 to a mean of 80.5 points and remained <span class="hlt">approximatively</span> constant at 3, 6 and 12 months follow-up. After 4 weeks 25.7% of the patients had no pain, 54.3% reported about pain relief. In the course of the follow-up a significant improvement of pain was observed: up to 80.8% painless and 19.2% pain relief 12 months after RSWT. Radiologically 4 weeks after RSWT the X-ray examination showed in 17.6% no calcific deposit, in 20.5% a disintegration and in 61.5% no changes of the calcific deposit. At further follow-up we found a complete resorption of the calcific deposit in 75% up to 12 months after RSWT and 25% had no change in calcific deposit. Overall three patients (8.5%) had to undergo surgical treatment 3-7 months after RSWT. The low-energy RSWT leads within the first 4 weeks to a significant pain relief and an improvement of shoulder function. In consideration of the long history, the size and the spontaneous resorption rate of the calcific deposit, an inductive effect of RSWT on the resorption of the calcific deposit can be assumed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ChOE...31..598X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ChOE...31..598X"><span>Theoretical <span class="hlt">approximation</span> of focusing-<span class="hlt">wave</span> induced load upon a large-scale vertical cylinder</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xue, Hong-xiang; Hu, Zhe; Tang, Wen-yong; Zhang, Xiao-ying; Wang, Kun-peng</p> <p>2017-10-01</p> <p>Until now, most researches into the rogue-<span class="hlt">wave</span>-structure interaction have relied on experimental measurement and numerical simulation. Owing to the complexity of the physical mechanism of rogue <span class="hlt">waves</span>, theoretical study on the <span class="hlt">wave</span>-structure issue still makes little progress. In this paper, the rogue <span class="hlt">wave</span> flow around a vertical cylinder is analytically studied within the scope of the potential theory. The rogue <span class="hlt">wave</span> is modeled by the Gauss envelope, which is one particular case of the well-known focusing theory. The formulae of the <span class="hlt">wave</span>-induced horizontal force and bending moment are proposed. For the convenience of engineering application, the derived formulae are simplified appropriately, and verified against numerical results. In addition, the influence of <span class="hlt">wave</span> parameters, such as the energy focusing degree and the <span class="hlt">wave</span> focusing position, is thoroughly investigated.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARE27013K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARE27013K"><span>Switching of the Spin-Density-<span class="hlt">Wave</span> in CeCoIn5 probed by Thermal Conductivity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Duk Y.; Lin, Shi-Zeng; Weickert, Franziska; Bauer, Eric D.; Ronning, Filip; Thompson, Joe D.; Movshovich, Roman</p> <p></p> <p>Unconventional superconductor CeCoIn5 orders magnetically in a spin-density-<span class="hlt">wave</span> (SDW) in the low-temperature and high-field corner of the superconducting phase. Recent neutron scattering experiment revealed that the single-domain SDW's ordering vector Q depends strongly on the direction of the magnetic field, switching sharply as the field is <span class="hlt">rotated</span> through the anti-nodal direction. This switching may be manifestation of a pair-density-<span class="hlt">wave</span> (PDW) p-<span class="hlt">wave</span> order parameter, which develops in addition to the well-established d-<span class="hlt">wave</span> order parameter due to the SDW formation. We have investigated the hypersensitivity of the magnetic domain with a thermal conductivity measurement. The heat current (J) was applied along the [110] direction such that the Q vector is either perpendicular or parallel to J, depending on the magnetic field direction. A discontinuous change of the thermal conductivity was observed when the magnetic field is <span class="hlt">rotated</span> around the [100] direction within 0 . 2° . The thermal conductivity with the Q parallel to the heat current (J ∥Q) is <span class="hlt">approximately</span> 15% lager than that with the Q perpendicular to the heat current (J ⊥Q). This result is consistent with additional gapping of the nodal quasiparticle by the p-<span class="hlt">wave</span> PDW coupled to SDW. Work at Los Alamos was performed under the auspices of the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1333886-automatic-software-correction-residual-aberrations-reconstructed-hrtem-exit-waves-crystalline-samples','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1333886-automatic-software-correction-residual-aberrations-reconstructed-hrtem-exit-waves-crystalline-samples"><span>Automatic software correction of residual aberrations in reconstructed HRTEM exit <span class="hlt">waves</span> of crystalline samples</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Ophus, Colin; Rasool, Haider I.; Linck, Martin; ...</p> <p>2016-11-30</p> <p>We develop an automatic and objective method to measure and correct residual aberrations in atomic-resolution HRTEM complex exit <span class="hlt">waves</span> for crystalline samples aligned along a low-index zone axis. Our method uses the <span class="hlt">approximate</span> <span class="hlt">rotational</span> point symmetry of a column of atoms or single atom to iteratively calculate a best-fit numerical phase plate for this symmetry condition, and does not require information about the sample thickness or precise structure. We apply our method to two experimental focal series reconstructions, imaging a β-Si 3N 4 wedge with O and N doping, and a single-layer graphene grain boundary. We use peak and latticemore » fitting to evaluate the precision of the corrected exit <span class="hlt">waves</span>. We also apply our method to the exit <span class="hlt">wave</span> of a Si wedge retrieved by off-axis electron holography. In all cases, the software correction of the residual aberration function improves the accuracy of the measured exit <span class="hlt">waves</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1333886-automatic-software-correction-residual-aberrations-reconstructed-hrtem-exit-waves-crystalline-samples','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1333886-automatic-software-correction-residual-aberrations-reconstructed-hrtem-exit-waves-crystalline-samples"><span>Automatic software correction of residual aberrations in reconstructed HRTEM exit <span class="hlt">waves</span> of crystalline samples</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ophus, Colin; Rasool, Haider I.; Linck, Martin</p> <p></p> <p>We develop an automatic and objective method to measure and correct residual aberrations in atomic-resolution HRTEM complex exit <span class="hlt">waves</span> for crystalline samples aligned along a low-index zone axis. Our method uses the <span class="hlt">approximate</span> <span class="hlt">rotational</span> point symmetry of a column of atoms or single atom to iteratively calculate a best-fit numerical phase plate for this symmetry condition, and does not require information about the sample thickness or precise structure. We apply our method to two experimental focal series reconstructions, imaging a β-Si 3N 4 wedge with O and N doping, and a single-layer graphene grain boundary. We use peak and latticemore » fitting to evaluate the precision of the corrected exit <span class="hlt">waves</span>. We also apply our method to the exit <span class="hlt">wave</span> of a Si wedge retrieved by off-axis electron holography. In all cases, the software correction of the residual aberration function improves the accuracy of the measured exit <span class="hlt">waves</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16712302','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16712302"><span>Polygons on a <span class="hlt">rotating</span> fluid surface.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jansson, Thomas R N; Haspang, Martin P; Jensen, Kåre H; Hersen, Pascal; Bohr, Tomas</p> <p>2006-05-05</p> <p>We report a novel and spectacular instability of a fluid surface in a <span class="hlt">rotating</span> system. In a flow driven by <span class="hlt">rotating</span> the bottom plate of a partially filled, stationary cylindrical container, the shape of the free surface can spontaneously break the axial symmetry and assume the form of a polygon <span class="hlt">rotating</span> rigidly with a speed different from that of the plate. With water, we have observed polygons with up to 6 corners. It has been known for many years that such flows are prone to symmetry breaking, but apparently the polygonal surface shapes have never been observed. The creation of <span class="hlt">rotating</span> internal <span class="hlt">waves</span> in a similar setup was observed for much lower <span class="hlt">rotation</span> rates, where the free surface remains essentially flat [J. M. Lopez, J. Fluid Mech. 502, 99 (2004). We speculate that the instability is caused by the strong azimuthal shear due to the stationary walls and that it is triggered by minute wobbling of the <span class="hlt">rotating</span> plate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.640a2059H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.640a2059H"><span>Instability of counter-<span class="hlt">rotating</span> stellar disks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hohlfeld, R. G.; Lovelace, R. V. E.</p> <p>2015-09-01</p> <p>We use an N-body simulation, constructed using GADGET-2, to investigate an accretion flow onto an astrophysical disk that is in the opposite sense to the disk's <span class="hlt">rotation</span>. In order to separate dynamics intrinsic to the counter-<span class="hlt">rotating</span> flow from the impact of the flow onto the disk, we consider an initial condition in which the counter-<span class="hlt">rotating</span> flow is in an annular region immediately exterior the main portion of the astrophysical disk. Such counter-<span class="hlt">rotating</span> flows are seen in systems such as NGC 4826 (known as the "Evil Eye Galaxy"). Interaction between the <span class="hlt">rotating</span> and counter-<span class="hlt">rotating</span> components is due to two-stream instability in the boundary region. A multi-armed spiral density <span class="hlt">wave</span> is excited in the astrophysical disk and a density distribution with high azimuthal mode number is excited in the counter-<span class="hlt">rotating</span> flow. Density fluctuations in the counter-<span class="hlt">rotating</span> flow aggregate into larger clumps and some of the material in the counter-<span class="hlt">rotating</span> flow is scattered to large radii. Accretion flow processes such as this are increasingly seen to be of importance in the evolution of multi-component galactic disks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950024358','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950024358"><span>Method for extracting forward acoustic <span class="hlt">wave</span> components from <span class="hlt">rotating</span> microphone measurements in the inlets of turbofan engines</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cicon, D. E.; Sofrin, T. G.</p> <p>1995-01-01</p> <p>This report describes a procedure for enhancing the use of the basic <span class="hlt">rotating</span> microphone system so as to determine the forward propagating mode components of the acoustic field in the inlet duct at the microphone plane in order to predict more accurate far-field radiation patterns. In addition, a modification was developed to obtain, from the same microphone readings, the forward acoustic modes generated at the fan face, which is generally some distance downstream of the microphone plane. Both these procedures employ computer-simulated calibrations of sound propagation in the inlet duct, based upon the current radiation code. These enhancement procedures were applied to previously obtained <span class="hlt">rotating</span> microphone data for the 17-inch ADP fan. The forward mode components at the microphone plane were obtained and were used to compute corresponding far-field directivities. The second main task of the program involved finding the forward <span class="hlt">wave</span> modes generated at the fan face in terms of the same total radial mode structure measured at the microphone plane. To obtain satisfactory results with the ADP geometry it was necessary to limit consideration to the propagating modes. Sensitivity studies were also conducted to establish guidelines for use in other fan configurations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780030858&hterms=poe&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dpoe','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780030858&hterms=poe&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dpoe"><span>Vibrational and <span class="hlt">rotational</span> transitions in low-energy electron-diatomic-molecule collisions. I - Close-coupling theory in the moving body-fixed frame. II - Hybrid theory and close-coupling theory: An /l subscript z-prime/-conserving close-coupling <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Choi, B. H.; Poe, R. T.</p> <p>1977-01-01</p> <p>A detailed vibrational-<span class="hlt">rotational</span> (V-R) close-coupling formulation of electron-diatomic-molecule scattering is developed in which the target molecular axis is chosen to be the z-axis and the resulting coupled differential equation is solved in the moving body-fixed frame throughout the entire interaction region. The coupled differential equation and asymptotic boundary conditions in the body-fixed frame are given for each parity, and procedures are outlined for evaluating V-R transition cross sections on the basis of the body-fixed transition and reactance matrix elements. Conditions are discussed for obtaining identical results from the space-fixed and body-fixed formulations in the case where a finite truncated basis set is used. The hybrid theory of Chandra and Temkin (1976) is then reformulated, relevant expressions and formulas for the simultaneous V-R transitions of the hybrid theory are obtained in the same forms as those of the V-R close-coupling theory, and distorted-<span class="hlt">wave</span> Born-<span class="hlt">approximation</span> expressions for the cross sections of the hybrid theory are presented. A close-coupling <span class="hlt">approximation</span> that conserves the internuclear axis component of the incident electronic angular momentum (l subscript z-prime) is derived from the V-R close-coupling formulation in the moving body-fixed frame.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvB..95u4305S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvB..95u4305S"><span>Diffusely scattered and transmitted elastic <span class="hlt">waves</span> by random rough solid-solid interfaces using an elastodynamic Kirchhoff <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, Fan; Lowe, Mike; Craster, Richard</p> <p>2017-06-01</p> <p>Elastic <span class="hlt">waves</span> scattered by random rough interfaces separating two distinct media play an important role in modeling phonon scattering and impact upon thermal transport models, and are also integral to ultrasonic inspection. We introduce theoretical formulas for the diffuse field of elastic <span class="hlt">waves</span> scattered by, and transmitted across, random rough solid-solid interfaces using the elastodynamic Kirchhoff <span class="hlt">approximation</span>. The new formulas are validated by comparison with numerical Monte Carlo simulations, for a wide range of roughness (rms σ ≤λ /3 , correlation length λ0≥ wavelength λ ), demonstrating a significant improvement over the widely used small-perturbation approach, which is valid only for surfaces with small rms values. Physical analysis using the theoretical formulas derived here demonstrates that increasing the rms value leads to a considerable change of the scattering patterns for each mode. The roughness has different effects on the reflection and the transmission, with a strong dependence on the material properties. In the special case of a perfect match of the <span class="hlt">wave</span> speed of the two solid media, the transmission is the same as the case for a flat interface. We pay particular attention to scattering in the specular direction, often used as an observable quantity, in terms of the roughness parameters, showing a peak at an intermediate value of rms; this rms value coincides with that predicted by the Rayleigh parameter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017RSPTA.37670093K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017RSPTA.37670093K"><span>Analytical <span class="hlt">approximation</span> and numerical simulations for periodic travelling water <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kalimeris, Konstantinos</p> <p>2017-12-01</p> <p>We present recent analytical and numerical results for two-dimensional periodic travelling water <span class="hlt">waves</span> with constant vorticity. The analytical approach is based on novel asymptotic expansions. We obtain numerical results in two different ways: the first is based on the solution of a constrained optimization problem, and the second is realized as a numerical continuation algorithm. Both methods are applied on some examples of non-constant vorticity. This article is part of the theme issue 'Nonlinear water <span class="hlt">waves</span>'.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/867971','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/867971"><span>In-line <span class="hlt">rotating</span> capacitive torque sensor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Kronberg, James W.</p> <p>1991-01-01</p> <p>A method and apparatus for measuring torques developed along a <span class="hlt">rotating</span> mechanical assembly comprising a <span class="hlt">rotating</span> inner portion and a stationary outer portion. The <span class="hlt">rotating</span> portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the <span class="hlt">rotating</span> portion. The capacitance between the outer, nonrotating and inner, <span class="hlt">rotating</span> portion varies with changes in the radial configuration of the <span class="hlt">rotating</span> portion. Signal output varies <span class="hlt">approximately</span> linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPlPh..81e3901B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPlPh..81e3901B"><span>Regular and chaotic dynamics of non-spherical bodies. Zeldovich's pancakes and emission of very long gravitational <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bisnovatyi-Kogan, G. S.; Tsupko, O. Yu.</p> <p>2015-10-01</p> <p>> In this paper we review a recently developed <span class="hlt">approximate</span> method for investigation of dynamics of compressible ellipsoidal figures. Collapse and subsequent behaviour are described by a system of ordinary differential equations for time evolution of semi-axes of a uniformly <span class="hlt">rotating</span>, three-axis, uniform-density ellipsoid. First, we apply this approach to investigate dynamic stability of non-spherical bodies. We solve the equations that describe, in a simplified way, the Newtonian dynamics of a self-gravitating non-<span class="hlt">rotating</span> spheroidal body. We find that, after loss of stability, a contraction to a singularity occurs only in a pure spherical collapse, and deviations from spherical symmetry prevent the contraction to the singularity through a stabilizing action of nonlinear non-spherical oscillations. The development of instability leads to the formation of a regularly or chaotically oscillating body, in which dynamical motion prevents the formation of the singularity. We find regions of chaotic and regular pulsations by constructing a Poincaré diagram. A real collapse occurs after damping of the oscillations because of energy losses, shock <span class="hlt">wave</span> formation or viscosity. We use our approach to investigate <span class="hlt">approximately</span> the first stages of collapse during the large scale structure formation. The theory of this process started from ideas of Ya. B. Zeldovich, concerning the formation of strongly non-spherical structures during nonlinear stages of the development of gravitational instability, known as `Zeldovich's pancakes'. In this paper the collapse of non-collisional dark matter and the formation of pancake structures are investigated <span class="hlt">approximately</span>. Violent relaxation, mass and angular momentum losses are taken into account phenomenologically. We estimate an emission of very long gravitational <span class="hlt">waves</span> during the collapse, and discuss the possibility of gravitational lensing and polarization of the cosmic microwave background by these <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1415893-broadband-integrated-polarization-rotator-using-three-layer-metallic-grating-structures','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1415893-broadband-integrated-polarization-rotator-using-three-layer-metallic-grating-structures"><span>Broadband integrated polarization <span class="hlt">rotator</span> using three-layer metallic grating structures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Fan, Ren -Hao; Liu, Dong; Peng, Ru -Wen; ...</p> <p>2018-01-05</p> <p>In this work, we demonstrate broadband integrated polarization <span class="hlt">rotator</span> (IPR) with a series of three-layer <span class="hlt">rotating</span> metallic grating structures. This transmissive optical IPR can conveniently <span class="hlt">rotate</span> the polarization of linearly polarized light to any desired directions at different spatial locations with high conversion efficiency, which is nearly constant for different <span class="hlt">rotation</span> angles. The linear polarization <span class="hlt">rotation</span> originates from multi-<span class="hlt">wave</span> interference in the three-layer grating structure. As a result, we anticipate that this type of IPR will find wide applications in analytical chemistry, biology, communication technology, imaging, etc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1415893-broadband-integrated-polarization-rotator-using-three-layer-metallic-grating-structures','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1415893-broadband-integrated-polarization-rotator-using-three-layer-metallic-grating-structures"><span>Broadband integrated polarization <span class="hlt">rotator</span> using three-layer metallic grating structures</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Fan, Ren -Hao; Liu, Dong; Peng, Ru -Wen</p> <p></p> <p>In this work, we demonstrate broadband integrated polarization <span class="hlt">rotator</span> (IPR) with a series of three-layer <span class="hlt">rotating</span> metallic grating structures. This transmissive optical IPR can conveniently <span class="hlt">rotate</span> the polarization of linearly polarized light to any desired directions at different spatial locations with high conversion efficiency, which is nearly constant for different <span class="hlt">rotation</span> angles. The linear polarization <span class="hlt">rotation</span> originates from multi-<span class="hlt">wave</span> interference in the three-layer grating structure. As a result, we anticipate that this type of IPR will find wide applications in analytical chemistry, biology, communication technology, imaging, etc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19700000545','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19700000545"><span>Novel <span class="hlt">wave</span> generator adaptable to indoor surfboarding</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Heidmann, M. F.; Phillips, B. R.</p> <p>1970-01-01</p> <p>Method is devised for generating strong acoustic <span class="hlt">waves</span> in confined body of water. Strong travelling acoustic <span class="hlt">waves</span> or modes are created by <span class="hlt">rotation</span> of radial jet of gas at center of short cylindrical chamber. Method and <span class="hlt">wave</span> structure suggest novel facility for water sports.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986RaSc...21..501C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986RaSc...21..501C"><span>Polarization <span class="hlt">rotation</span> in meteor burst communication systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cannon, P. S.</p> <p>1986-06-01</p> <p>Theoretical modeling of several meteor burst communication (MBC) paths indicates that polarization <span class="hlt">rotation</span> losses are significant for a linearly polarized system operating near 40 MHz. Losses for a hybrid system with physical installation problems, consisting of linearly polarized transmitting and circularly polarized receiving antennas, were found to be less. Both ionospheric Faraday <span class="hlt">rotation</span> polarization changes, and underdense meteor trail scattering <span class="hlt">wave</span> polarization <span class="hlt">rotation</span>, are considered. These losses are found to cause a 15-70 percent data throughput reduction of the value predicted for the situation without polarization <span class="hlt">rotation</span>, in the two 40-MHz linearly polarized links considered for noon summer solstice conditions during high solar sunspot number periods. Qualitative experimental confirmation is provided through a cross polarization approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JMoSp.335...43W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JMoSp.335...43W"><span>Newly assigned microwave transitions and a global analysis of the combined microwave/millimeter <span class="hlt">wave</span> <span class="hlt">rotational</span> spectra of 9-fluorenone and benzophenone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>West, Channing; Sedo, Galen; van Wijngaarden, Jennifer</p> <p>2017-05-01</p> <p>Microwave spectra of 9-fluorenone and benzophenone have been observed using a broadband chirped-pulse Fourier Transform Microwave (cp-FTMW) Spectrometer. An analysis of the microwave spectra allowed for the assignment of 178 b-type <span class="hlt">rotational</span> transitions for 9-fluorenone in the 8.0-13.0 GHz region, the assignment of 166 b-type transitions for benzophenone in the 8.0-14.0 GHz region, and effectively quadrupled the total number of pure <span class="hlt">rotational</span> transitions observed for these molecules. This new microwave data and the previously published millimeter <span class="hlt">wave</span> data of Maris et al. have been analyzed together in a global fit, where the resulting <span class="hlt">rotational</span> constants accurately reproduce the spectra over the entire 8-80 GHz region for both molecules. In addition, the resulting constants have been found to be consistent with the expected planar C2v structure for 9-fluorenone and the paddle-wheel like C2 structure of benzophenone. The <span class="hlt">rotational</span> constants of the combined global fit have allowed for a more precise determination of the inertial defects (Δ) and second moments of inertia (Pcc) for 9-fluoreneone and benzophenone. Specific focus has been paid to the second moment of benzophenone, which when used in conjunction with theory strongly suggests an ∼32.9° torsional angle out of the ab-plane for the paddle-wheel structure of the gas-phase molecule.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA544946','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA544946"><span>Operational Characteristics of a <span class="hlt">Rotating</span> Detonation Engine Using Hydrogen and Air</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2011-06-01</p> <p>Naval Research Laboratory PDE Pulsed detonation engine RDE <span class="hlt">Rotating</span> detonation engine TDW Transverse detonation <span class="hlt">wave</span> Symbols [SI units...primarily been on pulsed detonation engines ( PDEs ). Recently, however, detonation research has begun to also focus on <span class="hlt">rotating</span> , or continuous... <span class="hlt">rotating</span> detonation engines have been studied, however, more progress was initially made regarding PDEs . Recently, though, there has been a renewed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=exact+AND+solutions&pg=4&id=EJ196980','ERIC'); return false;" href="https://eric.ed.gov/?q=exact+AND+solutions&pg=4&id=EJ196980"><span>Application of the Parabolic <span class="hlt">Approximation</span> to Predict Acoustical Propagation in the Ocean.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>McDaniel, Suzanne T.</p> <p>1979-01-01</p> <p>A simplified derivation of the parabolic <span class="hlt">approximation</span> to the acoustical <span class="hlt">wave</span> equation is presented. Exact solutions to this <span class="hlt">approximate</span> equation are compared with solutions to the <span class="hlt">wave</span> equation to demonstrate the applicability of this method to the study of underwater sound propagation. (Author/BB)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22415536-rotational-study-nh-sub-co-complex-millimeter-wave-measurements-ab-initio-calculations','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22415536-rotational-study-nh-sub-co-complex-millimeter-wave-measurements-ab-initio-calculations"><span><span class="hlt">Rotational</span> study of the NH{sub 3}–CO complex: Millimeter-<span class="hlt">wave</span> measurements and ab initio calculations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Surin, L. A., E-mail: surin@ph1.uni-koeln.de; Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow; Potapov, A.</p> <p>2015-03-21</p> <p>The <span class="hlt">rotational</span> spectrum of the van der Waals complex NH{sub 3}–CO has been measured with the intracavity OROTRON jet spectrometer in the frequency range of 112–139 GHz. Newly observed and assigned transitions belong to the K = 0–0, K = 1–1, K = 1–0, and K = 2–1 subbands correlating with the rotationless (j{sub k}){sub NH3} = 0{sub 0} ground state of free ortho-NH{sub 3} and the K = 0–1 and K = 2–1 subbands correlating with the (j{sub k}){sub NH3} = 1{sub 1} ground state of free para-NH{sub 3}. The (<span class="hlt">approximate</span>) quantum number K is the projection of themore » total angular momentum J on the intermolecular axis. Some of these transitions are continuations to higher J values of transition series observed previously [C. Xia et al., Mol. Phys. 99, 643 (2001)], the other transitions constitute newly detected subbands. The new data were analyzed together with the known millimeter-<span class="hlt">wave</span> and microwave transitions in order to determine the molecular parameters of the ortho-NH{sub 3}–CO and para-NH{sub 3}–CO complexes. Accompanying ab initio calculations of the intermolecular potential energy surface (PES) of NH{sub 3}–CO has been carried out at the explicitly correlated coupled cluster level of theory with single, double, and perturbative triple excitations and an augmented correlation-consistent triple zeta basis set. The global minimum of the five-dimensional PES corresponds to an <span class="hlt">approximately</span> T-shaped structure with the N atom closest to the CO subunit and binding energy D{sub e} = 359.21 cm{sup −1}. The bound rovibrational levels of the NH{sub 3}–CO complex were calculated for total angular momentum J = 0–6 on this intermolecular potential surface and compared with the experimental results. The calculated dissociation energies D{sub 0} are 210.43 and 218.66 cm{sup −1} for ortho-NH{sub 3}–CO and para-NH{sub 3}–CO, respectively.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS1011a2088E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS1011a2088E"><span>Simulation of 2D <span class="hlt">Waves</span> in Circular Membrane Using Excel Spreadsheet with Visual Basic for Teaching Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eso, R.; Safiuddin, L. O.; Agusu, L.; Arfa, L. M. R. F.</p> <p>2018-04-01</p> <p>We propose a teaching instrument demonstrating the circular membrane <span class="hlt">waves</span> using the excel interactive spreadsheets with the Visual Basic for Application (VBA) programming. It is based on the analytic solution of circular membrane <span class="hlt">waves</span> involving Bessel function. The vibration modes and frequencies are determined by using Bessel <span class="hlt">approximation</span> and initial conditions. The 3D perspective based on the spreadsheets functions and facilities has been explored to show the 3D moving objects in transitional or <span class="hlt">rotational</span> processes. This instrument is very useful both in teaching activity and learning process of <span class="hlt">wave</span> physics. Visualizing of the vibration of <span class="hlt">waves</span> in the circular membrane which is showing a very clear manner of m and n vibration modes of the <span class="hlt">wave</span> in a certain frequency has been compared and matched to the experimental result using resonance method. The peak of deflection varies in time if the initial condition was working and have the same pattern with matlab simulation in zero initial velocity</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhNan..22...46Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhNan..22...46Q"><span>Evidence of iridescence in TiO2 nanostructures: An <span class="hlt">approximation</span> in plane <span class="hlt">wave</span> expansion method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quiroz, Heiddy P.; Barrera-Patiño, C. P.; Rey-González, R. R.; Dussan, A.</p> <p>2016-11-01</p> <p>Titanium dioxide nanotubes, TiO2 NTs, can be obtained by electrochemical anodization of Titanium sheets. After nanotubes are removed by mechanical stress, residual structures or traces on the surface of titanium sheets can be observed. These traces show iridescent effects. In this paper we carry out both experimental and theoretical study of those interesting and novel optical properties. For the experimental analysis we use angle resolved UV-vis spectroscopy while in the theoretical study is evaluated the photonic spectra using numerical simulations into the frequency-domain and the framework of the <span class="hlt">wave</span> plane <span class="hlt">approximation</span>. The iridescent effect is a strong property and independent of the sample. This behavior can be important to design new materials or compounds for several applications such as, cosmetic industry, optoelectronic devices, photocatalysis, sensors, among others.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720031449&hterms=gans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dgans','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720031449&hterms=gans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dgans"><span>On hydromagnetic oscillations in a <span class="hlt">rotating</span> cavity.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gans, R. F.</p> <p>1971-01-01</p> <p>Time-dependent hydromagnetic phenomena in a <span class="hlt">rotating</span> spherical cavity are investigated in the framework of an interior boundary-layer expansion. The first type of <span class="hlt">wave</span> is a modification of the hydrodynamic inertial <span class="hlt">wave</span>, the second is a pseudo-geostrophic <span class="hlt">wave</span> and is involved in spinup, and the third is related to the MAC <span class="hlt">waves</span> of Braginskii (1967). It is shown that the MAC <span class="hlt">waves</span> must satisfy more than the usual normal boundary conditions, and that reference must be made to the boundary-layer solution to resolve the ambiguity regarding which conditions are to be taken. The boundary-layer structure is investigated in detail to display the interactions between applied field, viscosity, electrical conductivity, frequency and latitu de.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhFl...28k2102K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhFl...28k2102K"><span>Dynamics of immiscible liquids in a <span class="hlt">rotating</span> horizontal cylinder</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kozlov, N. V.; Kozlova, A. N.; Shuvalova, D. A.</p> <p>2016-11-01</p> <p>The dynamics of an interface between two immiscible liquids of different density is studied experimentally in a horizontal cylinder at <span class="hlt">rotation</span> in the gravity field. Two liquids entirely fill the cavity volume, and the container is <span class="hlt">rotated</span> sufficiently fast so that the liquids are centrifuged. The light liquid forms a column extended along the <span class="hlt">rotation</span> axis, and the heavy liquid forms an annular layer. Under the action of gravity, the light liquid column displaces steadily along the radius, downwards in the laboratory frame. As a result, fluid oscillations in the cavity frame are excited at the interface, which lead to the generation of a steady streaming, and the fluid comes into a slow lagging <span class="hlt">rotation</span> with respect to the cylinder walls. The dynamics of the studied system is determined by the ratio of the gravity acceleration to the centrifugal one—the dimensionless acceleration. In experiments, the system is controlled by the means of variation of the <span class="hlt">rotation</span> rate, i.e., of the centrifugal force. At a critical value of the dimensionless acceleration the circular interface looses stability, and an azimuthal <span class="hlt">wave</span> is excited. This leads to a strong increase in the interface differential velocity. A theoretical analysis is done based on the theory of centrifugal <span class="hlt">waves</span> and a frequency equation is obtained. Experimental results are in good agreement with the theory at the condition of small <span class="hlt">wave</span> amplitudes. Mechanism of steady streaming generation is analyzed based on previously published theoretical results obtained for the limiting case when the light phase is a solid cylinder. A qualitative agreement is found.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7274769','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/biblio/7274769"><span>In-line <span class="hlt">rotating</span> capacitive torque sensor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Kronberg, J.W.</p> <p>1991-09-10</p> <p>Disclosed are a method and apparatus for measuring torques developed along a <span class="hlt">rotating</span> mechanical assembly comprising a <span class="hlt">rotating</span> inner portion and a stationary outer portion. The <span class="hlt">rotating</span> portion has an electrically-conductive flexing section fitted between two coaxial shafts in a configuration which varies radially in accordance with applied torque. The stationary portion comprises a plurality of conductive plates forming a surface concentric with and having a diameter slightly larger than the diameter of the <span class="hlt">rotating</span> portion. The capacitance between the outer, nonrotating and inner, <span class="hlt">rotating</span> portion varies with changes in the radial configuration of the <span class="hlt">rotating</span> portion. Signal output varies <span class="hlt">approximately</span> linearly with torque for small torques, nonlinearly for larger torques. The sensor is preferably surrounded by a conductive shell to minimize electrical interference from external sources. 18 figures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhLA..382.1633L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhLA..382.1633L"><span>Effect of Floquet engineering on the p-<span class="hlt">wave</span> superconductor with second-neighbor couplings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, X. P.; Li, C. F.; Wang, L. C.; Zhou, L.</p> <p>2018-06-01</p> <p>The influence of the Floquet engineering on a particular one-dimensional p-<span class="hlt">wave</span> superconductor, Kitaev model, with second-neighbor couplings is investigated in this paper. The effective Hamiltonians in the <span class="hlt">rotated</span> reference frames have been obtained, and the convergent regions of the <span class="hlt">approximated</span> Hamiltonian as well as the topological phase diagrams have been analyzed and discussed. We show that by modulating the external driving field amplitude, frequency as well as the second-neighbor hopping amplitude, the rich phase diagrams and transitions between different topological phases can be obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ASPC..466..231S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ASPC..466..231S"><span>The Maximum Mass of <span class="hlt">Rotating</span> Strange Stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Szkudlarek, M.; Gondek-Rosiń; ska, D.; Villain, L.; Ansorg, M.</p> <p>2012-12-01</p> <p>Strange quark stars are considered as a possible alternative to neutron stars as compact objects (e.g. Weber 2003). A hot compact star (a proto-neutron star or a strange star) born in a supernova explosion or a remnant of neutron stars binary merger are expected to <span class="hlt">rotate</span> differentially and be important sources of gravitational <span class="hlt">waves</span>. We present results of the first relativistic calculations of differentially <span class="hlt">rotating</span> strange quark stars for broad ranges of degree of differential <span class="hlt">rotation</span> and maximum densities. Using a highly accurate, relativistic code we show that <span class="hlt">rotation</span> may cause a significant increase of maximum allowed mass of strange stars, much larger than in the case of neutron stars with the same degree of differential <span class="hlt">rotation</span>. Depending on the maximum allowed mass a massive neutron star (strange star) can be temporarily stabilized by differential <span class="hlt">rotation</span> or collapse to a black hole.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JAP...123b4904V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JAP...123b4904V"><span>Nonlinear mechanisms of two-dimensional <span class="hlt">wave-wave</span> transformations in the initially coupled acoustic structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vorotnikov, K.; Starosvetsky, Y.</p> <p>2018-01-01</p> <p>The present study concerns two-dimensional nonlinear mechanisms of bidirectional and unidirectional channeling of longitudinal and shear <span class="hlt">waves</span> emerging in the locally resonant acoustic structure. The system under consideration comprises an oscillatory chain of the axially coupled masses. Each mass of the chain is subject to the local linear potential along the lateral direction and incorporates the lightweight internal <span class="hlt">rotator</span>. In the present work, we demonstrate the emergence of special resonant regimes of complete bi- and unidirectional transitions between the longitudinal and the shear <span class="hlt">waves</span> of the locally resonant chain. These regimes are manifested by the two-dimensional energy channeling between the longitudinal and the shear traveling <span class="hlt">waves</span> in the recurrent as well as the irreversible fashion. We show that the spatial control of the two dimensional energy flow between the longitudinal and the shear <span class="hlt">waves</span> is solely governed by the motion of the internal <span class="hlt">rotators</span>. Nonlinear analysis of the regimes of a bidirectional <span class="hlt">wave</span> channeling unveils their global bifurcation structure and predicts the zones of their spontaneous transitions from a complete bi-directional <span class="hlt">wave</span> channeling to the one-directional entrapment. An additional regime of a complete irreversible resonant transformation of the longitudinal <span class="hlt">wave</span> into a shear <span class="hlt">wave</span> is analyzed in the study. The intrinsic mechanism governing the unidirectional <span class="hlt">wave</span> reorientation is described analytically. The results of the analysis of both mechanisms are substantiated by the numerical simulations of the full model and are found to be in a good agreement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20718207-coherent-control-ultrafast-optical-four-wave-mixing-two-color-omega-omega-laser-pulses','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20718207-coherent-control-ultrafast-optical-four-wave-mixing-two-color-omega-omega-laser-pulses"><span>Coherent control of ultrafast optical four-<span class="hlt">wave</span> mixing with two-color {omega}-3{omega} laser pulses</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Serrat, Carles</p> <p>2005-08-15</p> <p>A theoretical investigation on the coherent control of optical transient four-<span class="hlt">wave</span> mixing interactions in two-level systems with two intense few-cycle propagating laser pulses of central angular frequencies {omega} and 3{omega} is reported. By numerically solving the full Maxwell-Bloch equations beyond the slowly varying envelope and <span class="hlt">rotating-wave</span> <span class="hlt">approximations</span> in the time domain, the nonlinear coupling to the optical field at frequency 5{omega} is found to depend critically on the initial relative phase {phi} of the propagating pulses: the coupling is enhanced when the pulses interfere constructively in the center ({phi}=0), while it is nearly suppressed when they are out of phasemore » ({phi}={pi})« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG14A..02P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG14A..02P"><span>Drift <span class="hlt">waves</span> control using emissive cathodes in the laboratory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Plihon, N.; Desangles, V.; De Giorgio, E.; Bousselin, G.; Marino, R.; Pustelnik, N.; Poye, A.</p> <p>2017-12-01</p> <p>Low frequency plasma fluctuations are known to be the cause of strong transport perpendicular to magnetic guiding field line. These low frequency drift <span class="hlt">waves</span> have been studied in linear devices in the laboratory over the last two decades. Their excitation or mitigation have been addressed using different drives, such as ring biasing or electromagnetic low frequency fields. Here we present an experimental characterization of the behavior of drift <span class="hlt">waves</span> when the profile of the background plasma <span class="hlt">rotation</span> is controlled using hot emissive cathodes. We show that electron emission from the cathodes modify the plasma potential, which in turn controls the <span class="hlt">rotation</span> profile. Mitigation or enhancement of drift <span class="hlt">waves</span> (on the amplitude or azimuthal mode number) is observed depending on the plasma <span class="hlt">rotation</span> profile.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA584603','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA584603"><span>Heat Exchanger Design and Testing for a 6-Inch <span class="hlt">Rotating</span> Detonation Engine</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2013-03-01</p> <p>Engine Research Facility HHV Higher heating value LHV Lower heating value PDE Pulsed detonation engine RDE <span class="hlt">Rotating</span> detonation engine RTD...the combustion community are pulse detonation engines ( PDEs ) and <span class="hlt">rotating</span> detonation engines (RDEs). 1.1 Differences between Pulsed and <span class="hlt">Rotating</span> ...steadier than that of a PDE (2, 3). (2) (3) Figure 1. Unrolled <span class="hlt">rotating</span> detonation <span class="hlt">wave</span> from high-speed video (4) Another difference that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JMoSp.342..125Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JMoSp.342..125Z"><span>Millimeter and submillimeter <span class="hlt">wave</span> spectroscopy of propanal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zingsheim, Oliver; Müller, Holger S. P.; Lewen, Frank; Jørgensen, Jes K.; Schlemmer, Stephan</p> <p>2017-12-01</p> <p>The <span class="hlt">rotational</span> spectra of the two stable conformers syn- and gauche-propanal (CH3CH2CHO) were studied in the millimeter and submillimeter <span class="hlt">wave</span> regions from 75 to 500 GHz with the Cologne (Sub-)Millimeter <span class="hlt">wave</span> Spectrometer. Furthermore, the first excited states associated with the aldehyde torsion and with the methyl torsion, respectively, of the syn-conformer were analyzed. The newly obtained spectroscopic parameters yield better predictions, thus fulfill sensitivity and resolution requirements in new astronomical observations in order to unambiguously assign pure <span class="hlt">rotational</span> transitions of propanal. This is demonstrated on a radio astronomical spectrum from the Atacama Large Millimeter/submillimeter Array Protostellar Interferometric Line Survey (ALMA-PILS). In particular, an accurate description of observed splittings, caused by internal <span class="hlt">rotation</span> of the methyl group in the syn-conformer and by tunneling <span class="hlt">rotation</span> interaction from two stable degenerate gauche-conformers, is reported. The <span class="hlt">rotational</span> spectrum of propanal is of additional interest because of its two large amplitude motions pertaining to the methyl and the aldehyde group, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EP%26S...69..162W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EP%26S...69..162W"><span>Application of a simplified calculation for full-<span class="hlt">wave</span> microtremor H/ V spectral ratio based on the diffuse field <span class="hlt">approximation</span> to identify underground velocity structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Hao; Masaki, Kazuaki; Irikura, Kojiro; Sánchez-Sesma, Francisco José</p> <p>2017-12-01</p> <p>Under the diffuse field <span class="hlt">approximation</span>, the full-<span class="hlt">wave</span> (FW) microtremor H/ V spectral ratio ( H/ V) is modeled as the square root of the ratio of the sum of imaginary parts of the Green's function of the horizontal components to that of the vertical one. For a given layered medium, the FW H/ V can be well <span class="hlt">approximated</span> with only surface <span class="hlt">waves</span> (SW) H/ V of the "cap-layered" medium which consists of the given layered medium and a new larger velocity half-space (cap layer) at large depth. Because the contribution of surface <span class="hlt">waves</span> can be simply obtained by the residue theorem, the computation of SW H/ V of cap-layered medium is faster than that of FW H/ V evaluated by discrete wavenumber method and contour integration method. The simplified computation of SW H/ V was then applied to identify the underground velocity structures at six KiK-net strong-motion stations. The inverted underground velocity structures were used to evaluate FW H/ Vs which were consistent with the SW H/ Vs of corresponding cap-layered media. The previous study on surface <span class="hlt">waves</span> H/ Vs proposed with the distributed surface sources assumption and a fixed Rayleigh-to-Love <span class="hlt">waves</span> amplitude ratio for horizontal motions showed a good agreement with the SW H/ Vs of our study. The consistency between observed and theoretical spectral ratios, such as the earthquake motions of H/ V spectral ratio and spectral ratio of horizontal motions between surface and bottom of borehole, indicated that the underground velocity structures identified from SW H/ V of cap-layered medium were well resolved by the new method.[Figure not available: see fulltext.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhPl...25c2111U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhPl...25c2111U"><span>Helicons in uniform fields. I. <span class="hlt">Wave</span> diagnostics with hodograms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Urrutia, J. M.; Stenzel, R. L.</p> <p>2018-03-01</p> <p>The <span class="hlt">wave</span> equation for whistler <span class="hlt">waves</span> is well known and has been solved in Cartesian and cylindrical coordinates, yielding plane <span class="hlt">waves</span> and cylindrical <span class="hlt">waves</span>. In space plasmas, <span class="hlt">waves</span> are usually assumed to be plane <span class="hlt">waves</span>; in small laboratory plasmas, they are often assumed to be cylindrical "helicon" eigenmodes. Experimental observations fall in between both models. Real <span class="hlt">waves</span> are usually bounded and may <span class="hlt">rotate</span> like helicons. Such helicons are studied experimentally in a large laboratory plasma which is essentially a uniform, unbounded plasma. The <span class="hlt">waves</span> are excited by loop antennas whose properties determine the field <span class="hlt">rotation</span> and transverse dimensions. Both m = 0 and m = 1 helicon modes are produced and analyzed by measuring the <span class="hlt">wave</span> magnetic field in three dimensional space and time. From Ampère's law and Ohm's law, the current density and electric field vectors are obtained. Hodograms for these vectors are produced. The sign ambiguity of the hodogram normal with respect to the direction of <span class="hlt">wave</span> propagation is demonstrated. In general, electric and magnetic hodograms differ but both together yield the <span class="hlt">wave</span> vector direction unambiguously. Vector fields of the hodogram normal yield the phase flow including phase <span class="hlt">rotation</span> for helicons. Some helicons can have locally a linear polarization which is identified by the hodogram ellipticity. Alternatively the amplitude oscillation in time yields a measure for the <span class="hlt">wave</span> polarization. It is shown that <span class="hlt">wave</span> interference produces linear polarization. These observations emphasize that single point hodogram measurements are inadequate to determine the <span class="hlt">wave</span> topology unless assuming plane <span class="hlt">waves</span>. Observations of linear polarization indicate <span class="hlt">wave</span> packets but not plane <span class="hlt">waves</span>. A simple qualitative diagnostics for the <span class="hlt">wave</span> polarization is the measurement of the magnetic field magnitude in time. Circular polarization has a constant amplitude; linear polarization results in amplitude modulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890015794','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890015794"><span>Structural tailoring of counter <span class="hlt">rotation</span> propfans</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Brown, Kenneth W.; Hopkins, D. A.</p> <p>1989-01-01</p> <p>The STAT program was designed for the optimization of single <span class="hlt">rotation</span>, tractor propfan designs. New propfan designs, however, generally consist of two counter <span class="hlt">rotating</span> propfan rotors. STAT is constructed to contain two levels of analysis. An interior loop, consisting of accurate, efficient <span class="hlt">approximate</span> analyses, is used to perform the primary propfan optimization. Once an optimum design has been obtained, a series of refined analyses are conducted. These analyses, while too computer time expensive for the optimization loop, are of sufficient accuracy to validate the optimized design. Should the design prove to be unacceptable, provisions are made for recalibration of the <span class="hlt">approximate</span> analyses, for subsequent reoptimization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018A%26A...613A..45A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018A%26A...613A..45A"><span>Semidiurnal thermal tides in asynchronously <span class="hlt">rotating</span> hot Jupiters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Auclair-Desrotour, P.; Leconte, J.</p> <p>2018-05-01</p> <p>Context. Thermal tides can torque the atmosphere of hot Jupiters into asynchronous <span class="hlt">rotation</span>, while these planets are usually assumed to be locked into spin-orbit synchronization with their host star. Aims: In this work, our goal is to characterize the tidal response of a <span class="hlt">rotating</span> hot Jupiter to the tidal semidiurnal thermal forcing of its host star by identifying the structure of tidal <span class="hlt">waves</span> responsible for variation of mass distribution, their dependence on the tidal frequency, and their ability to generate strong zonal flows. Methods: We develop an ab initio global modelling that generalizes the early approach of Arras & Socrates (2010, ApJ, 714, 1) to <span class="hlt">rotating</span> and non-adiabatic planets. We analytically derive the torque exerted on the body and the associated timescales of evolution, as well as the equilibrium tidal response of the atmosphere in the zero-frequency limit. Finally, we numerically integrate the equations of thermal tides for three cases, including dissipation and <span class="hlt">rotation</span> step by step. Results: The resonances associated with tidally generated gravito-inertial <span class="hlt">waves</span> significantly amplify the resulting tidal torque in the range 1-30 days. This torque can globally drive the atmosphere into asynchronous <span class="hlt">rotation</span>, as its sign depends on the tidal frequency. The resonant behaviour of the tidal response is enhanced by <span class="hlt">rotation</span>, which couples the forcing to several Hough modes in the general case, while the radiative cooling tends to regularize it and diminish its amplitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009FlDy...44L.759K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009FlDy...44L.759K"><span>Poincare oscillations and geostrophic adjustment in a <span class="hlt">rotating</span> paraboloid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kalashnik, M.; Kakhiani, V.; Patarashvili, K.; Tsakadze, S.</p> <p>2009-10-01</p> <p>Free liquid oscillations (Poincare oscillations) in a <span class="hlt">rotating</span> paraboloid are investigated theoretically and experimentally. Within the framework of shallow-water theory, with account for the centrifugal force, expressions for the free oscillation frequencies are obtained and corrections to the frequencies related with the finiteness of the liquid depth are found. It is shown that in the <span class="hlt">rotating</span> liquid, apart from the <span class="hlt">wave</span> modes of free oscillations, a stationary vortex mode is also generated, that is, a process of geostrophic adjustment takes place. Solutions of the shallow-water equations which describe the <span class="hlt">wave</span> dynamics of the adjustment process are presented. In the experiments performed the <span class="hlt">wave</span> and vortex modes were excited by removing a previously immersed hemisphere from the central part of the paraboloid. Good agreement between theory and experiment was obtained. Address: alex_gaina@yahoo.com Database: phy</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DPS....4730705F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DPS....4730705F"><span><span class="hlt">Rotation</span> Frequencies of Small Jovian Trojan Asteroids: An Excess of Slow <span class="hlt">Rotators</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>French, Linda M.; Stephens, Robert D.; James, David J.; Coley, Daniel; Connour, Kyle</p> <p>2015-11-01</p> <p>Several lines of evidence support a common origin for, and possible hereditary link between, cometary nuclei and jovian Trojan asteroids. Due to their distance and low albedos, few comet-sized Trojans have been studied. We discuss the <span class="hlt">rotation</span> properties of Jovian Trojan asteroids less than 30 km in diameter. <span class="hlt">Approximately</span> half the 131 objects discussed here were studied using densely sampled lightcurves (French et al. 2015a, b); Stephens et al. 2015), and the other half were sparse lightcurves obtained by the Palomar Transient Factory (PTF; Waszcazk et al. 2015).A significant fraction (~40%) of the objects in the ground-based sample <span class="hlt">rotate</span> slowly (P > 24h), with measured periods as long as 375 h (Warner and Stephens 2011). The PTF data show a similar excess of slow <span class="hlt">rotators</span>. Only 5 objects in the combined data set have <span class="hlt">rotation</span> periods of less than six hours. Three of these fast <span class="hlt">rotators</span> were contained in the data set of French et al. these three had a geometric mean <span class="hlt">rotation</span> period of 5.29 hours. A prolate spheroid held together by gravity <span class="hlt">rotating</span> with this period would have a critical density of 0.43 gm/cm3, a density similar to that of comets (Lamy et al. 2004).Harris et al. (2012) and Warner et al. (2011) have explored the possible effects on asteroid <span class="hlt">rotational</span> statistics with the results from wide-field surveys. We will examine Trojan <span class="hlt">rotation</span> statistics with and without the results from the PTF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMDI33B0405Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMDI33B0405Y"><span>Temporal Change of Seismic Earth's Inner Core Phases: Inner Core Differential <span class="hlt">Rotation</span> Or Temporal Change of Inner Core Surface?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, J.; Tian, D.; Sun, L.; Wen, L.</p> <p>2017-12-01</p> <p>Since Song and Richards [1996] first reported seismic evidence for temporal change of PKIKP <span class="hlt">wave</span> (a compressional <span class="hlt">wave</span> refracted in the inner core) and proposed inner core differential <span class="hlt">rotation</span> as its explanation, it has generated enormous interests in the scientific community and the public, and has motivated many studies on the implications of the inner core differential <span class="hlt">rotation</span>. However, since Wen [2006] reported seismic evidence for temporal change of PKiKP <span class="hlt">wave</span> (a compressional <span class="hlt">wave</span> reflected from the inner core boundary) that requires temporal change of inner core surface, both interpretations for the temporal change of inner core phases have existed, i.e., inner core <span class="hlt">rotation</span> and temporal change of inner core surface. In this study, we discuss the issue of the interpretation of the observed temporal changes of those inner core phases and conclude that inner core differential <span class="hlt">rotation</span> is not only not required but also in contradiction with three lines of seismic evidence from global repeating earthquakes. Firstly, inner core differential <span class="hlt">rotation</span> provides an implausible explanation for a disappearing inner core scatterer between a doublet in South Sandwich Islands (SSI), which is located to be beneath northern Brazil based on PKIKP and PKiKP coda <span class="hlt">waves</span> of the earlier event of the doublet. Secondly, temporal change of PKIKP and its coda <span class="hlt">waves</span> among a cluster in SSI is inconsistent with the interpretation of inner core differential <span class="hlt">rotation</span>, with one set of the data requiring inner core <span class="hlt">rotation</span> and the other requiring non-<span class="hlt">rotation</span>. Thirdly, it's not reasonable to invoke inner core differential <span class="hlt">rotation</span> to explain travel time change of PKiKP <span class="hlt">waves</span> in a very small time scale (several months), which is observed for repeating earthquakes in Middle America subduction zone. On the other hand, temporal change of inner core surface could provide a consistent explanation for all the observed temporal changes of PKIKP and PKiKP and their coda <span class="hlt">waves</span>. We conclude that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009A%26A...506.1215O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009A%26A...506.1215O"><span>The propagation of the shock <span class="hlt">wave</span> from a strong explosion in a plane-parallel stratified medium: the Kompaneets <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olano, C. A.</p> <p>2009-11-01</p> <p>Context: Using certain simplifications, Kompaneets derived a partial differential equation that states the local geometrical and kinematical conditions that each surface element of a shock <span class="hlt">wave</span>, created by a point blast in a stratified gaseous medium, must satisfy. Kompaneets could solve his equation analytically for the case of a <span class="hlt">wave</span> propagating in an exponentially stratified medium, obtaining the form of the shock front at progressive evolutionary stages. Complete analytical solutions of the Kompaneets equation for shock <span class="hlt">wave</span> motion in further plane-parallel stratified media were not found, except for radially stratified media. Aims: We aim to analytically solve the Kompaneets equation for the motion of a shock <span class="hlt">wave</span> in different plane-parallel stratified media that can reflect a wide variety of astrophysical contexts. We were particularly interested in solving the Kompaneets equation for a strong explosion in the interstellar medium of the Galactic disk, in which, due to intense winds and explosions of stars, gigantic gaseous structures known as superbubbles and supershells are formed. Methods: Using the Kompaneets <span class="hlt">approximation</span>, we derived a pair of equations that we call adapted Kompaneets equations, that govern the propagation of a shock <span class="hlt">wave</span> in a stratified medium and that permit us to obtain solutions in parametric form. The solutions provided by the system of adapted Kompaneets equations are equivalent to those of the Kompaneets equation. We solved the adapted Kompaneets equations for shock <span class="hlt">wave</span> propagation in a generic stratified medium by means of a power-series method. Results: Using the series solution for a shock <span class="hlt">wave</span> in a generic medium, we obtained the series solutions for four specific media whose respective density distributions in the direction perpendicular to the stratification plane are of an exponential, power-law type (one with exponent k=-1 and the other with k =-2) and a quadratic hyperbolic-secant. From these series solutions, we deduced</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910054173&hterms=film+analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dfilm%2Banalysis','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910054173&hterms=film+analysis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dfilm%2Banalysis"><span>The flow of a thin liquid film on a stationary and <span class="hlt">rotating</span> disk. I - Experimental analysis and flow visualization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thomas, S.; Faghri, A.; Hankey, W.</p> <p>1990-01-01</p> <p>The mean thickness of a thin liquid film of deionized water with a free surface on a stationary and <span class="hlt">rotating</span> horizontal disk has been measured with a nonobtrusive capacitance technique. The measurements were taken when the <span class="hlt">rotational</span> speed was 0-300 RPM and the flow rate was 7.0-15.0 LPM. A flow visualization study of the thin film was also performed to determine the characteristics of the <span class="hlt">waves</span> on the free surface. When the disk was stationary, a circular hydraulic jump was present on the disk. Surface <span class="hlt">waves</span> were found in the supercritical and subcritical regions at all flow rates studied. When the <span class="hlt">rotational</span> speed of the disk is low, a standing <span class="hlt">wave</span> at the edge of the disk was present. As the <span class="hlt">rotational</span> speed increased, the surface <span class="hlt">waves</span> changed from the wavy-laminar region to a region in which the <span class="hlt">waves</span> ran nearly radially across the disk on top of a thin substrate of fluid.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRC..123.2381H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRC..123.2381H"><span>Generation and Propagation of Nonlinear Internal <span class="hlt">Waves</span> in Sheared Currents Over the Washington Continental Shelf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hamann, Madeleine M.; Alford, Matthew H.; Mickett, John B.</p> <p>2018-04-01</p> <p>The generation, propagation, and dissipation of nonlinear internal <span class="hlt">waves</span> (NLIW) in sheared background currents is examined using 7 days of shipboard microstructure surveys and two moorings on the continental shelf offshore of Washington state. Surveys near the hypothesized generation region show semi-diurnal (D2) energy flux is onshore and that the ratio of energy flux to group speed times energy (F/cgE) increases sharply at the shelf break, suggesting that the incident D2 internal tide is partially reflected and partially transmitted. NLIW appear at an inshore mooring at the leading edge of the onshore phase of the baroclinic tide, consistent with nonlinear transformation of the shoaling internal tide as their generation mechanism. Of the D2 energy flux observed at the eastern extent of the generation region (133 ± 18 Wm-1), <span class="hlt">approximately</span> 30% goes into the NLIW observed inshore (36 ± 11 Wm-1). Inshore of the moorings, 7 <span class="hlt">waves</span> are tracked into shallow (30-40 m) water, where a vertically sheared, southward current becomes strong. As train-like <span class="hlt">waves</span> propagate onshore, <span class="hlt">wave</span> amplitudes of 25-30 m and energies of 5 MJ decrease to 12 m and 10 kJ, respectively. The observed direction of propagation <span class="hlt">rotates</span> from 30° N of E to ˜30° S of E in the strongly sheared region. Linear ray tracing using the Taylor-Goldstein equation to incorporate parallel shear effects accounts for only a small portion of the observed <span class="hlt">rotation</span>, suggesting that three-dimensionality of the <span class="hlt">wave</span> crests and the background currents is important here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT........87C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT........87C"><span>Nonlinear Schroedinger <span class="hlt">Approximations</span> for Partial Differential Equations with Quadratic and Quasilinear Terms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cummings, Patrick</p> <p></p> <p>We consider the <span class="hlt">approximation</span> of solutions of two complicated, physical systems via the nonlinear Schrodinger equation (NLS). In particular, we discuss the evolution of <span class="hlt">wave</span> packets and long <span class="hlt">waves</span> in two physical models. Due to the complicated nature of the equations governing many physical systems and the in-depth knowledge we have for solutions of the nonlinear Schrodinger equation, it is advantageous to use <span class="hlt">approximation</span> results of this kind to model these physical systems. The <span class="hlt">approximations</span> are simple enough that we can use them to understand the qualitative and quantitative behavior of the solutions, and by justifying them we can show that the behavior of the <span class="hlt">approximation</span> captures the behavior of solutions to the original equation, at least for long, but finite time. We first consider a model of the water <span class="hlt">wave</span> equations which can be <span class="hlt">approximated</span> by <span class="hlt">wave</span> packets using the NLS equation. We discuss a new proof that both simplifies and strengthens previous justification results of Schneider and Wayne. Rather than using analytic norms, as was done by Schneider and Wayne, we construct a modified energy functional so that the <span class="hlt">approximation</span> holds for the full interval of existence of the <span class="hlt">approximate</span> NLS solution as opposed to a subinterval (as is seen in the analytic case). Furthermore, the proof avoids problems associated with inverting the normal form transform by working with a modified energy functional motivated by Craig and Hunter et al. We then consider the Klein-Gordon-Zakharov system and prove a long <span class="hlt">wave</span> <span class="hlt">approximation</span> result. In this case there is a non-trivial resonance that cannot be eliminated via a normal form transform. By combining the normal form transform for small Fourier modes and using analytic norms elsewhere, we can get a justification result on the order 1 over epsilon squared time scale.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000ApJ...528L..29B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000ApJ...528L..29B"><span>On the Maximum Mass of Differentially <span class="hlt">Rotating</span> Neutron Stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baumgarte, Thomas W.; Shapiro, Stuart L.; Shibata, Masaru</p> <p>2000-01-01</p> <p>We construct relativistic equilibrium models of differentially <span class="hlt">rotating</span> neutron stars and show that they can support significantly more mass than their nonrotating or uniformly <span class="hlt">rotating</span> counterparts. We dynamically evolve such ``hypermassive'' models in full general relativity and show that there do exist configurations that are dynamically stable against radial collapse and bar formation. Our results suggest that the remnant of binary neutron star coalescence may be temporarily stabilized by differential <span class="hlt">rotation</span>, leading to delayed collapse and a delayed gravitational <span class="hlt">wave</span> burst.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018A%26A...611A..47Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018A%26A...611A..47Z"><span>Propagating <span class="hlt">wave</span> in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, B.; Hou, Y. J.; Zhang, J.</p> <p>2018-03-01</p> <p>Aims: We aim to ascertain the physical parameters of a propagating <span class="hlt">wave</span> over the solar disk detected by the Interface Region Imaging Spectrograph (IRIS). Methods: Using imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked bright spots to determine the parameters of a propagating transverse <span class="hlt">wave</span> in active region (AR) loops triggered by activation of a filament. Deriving the Doppler velocity of Si IV line from spectral observations of IRIS, we have determined the <span class="hlt">rotating</span> directions of active region loops which are relevant to the <span class="hlt">wave</span>. Results: On 2015 December 19, a filament was located on the polarity inversion line of the NOAA AR 12470. The filament was activated and then caused a C1.1 two-ribbon flare. Between the flare ribbons, two <span class="hlt">rotation</span> motions of a set of bright loops were observed to appear in turn with opposite directions. Following the end of the second <span class="hlt">rotation</span>, a propagating <span class="hlt">wave</span> and an associated transverse oscillation were detected in these bright loops. In 1400 Å channel, there was bright material flowing along the loops in a <span class="hlt">wave</span>-like manner, with a period of 128 s and a mean amplitude of 880 km. For the transverse oscillation, we tracked a given loop and determine the transverse positions of the tracking loop in a limited longitudinal range. In both of 1400 Å and 171 Å channels, <span class="hlt">approximately</span> four periods are distinguished during the transverse oscillation. The mean period of the oscillation is estimated as 143 s and the displacement amplitude as between 1370 km and 690 km. We interpret these oscillations as a propagating kink <span class="hlt">wave</span> and obtain its speed of 1400 km s-1. Conclusions: Our observations reveal that a flare associated with filament activation could trigger a kink propagating <span class="hlt">wave</span> in active region loops over the solar disk. Movies associated to Figs. 1-4 are available at http://https://www.aanda.org</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790042015&hterms=Kohn&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DKohn','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790042015&hterms=Kohn&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DKohn"><span>Variationally consistent <span class="hlt">approximation</span> scheme for charge transfer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Halpern, A. M.</p> <p>1978-01-01</p> <p>The author has developed a technique for testing various charge-transfer <span class="hlt">approximation</span> schemes for consistency with the requirements of the Kohn variational principle for the amplitude to guarantee that the amplitude is correct to second order in the scattering <span class="hlt">wave</span> functions. Applied to Born-type <span class="hlt">approximations</span> for charge transfer it allows the selection of particular groups of first-, second-, and higher-Born-type terms that obey the consistency requirement, and hence yield more reliable <span class="hlt">approximation</span> to the amplitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22410444-relativistic-electron-scattering-magnetosonic-waves-effects-discrete-wave-emission-high-wave-amplitudes','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22410444-relativistic-electron-scattering-magnetosonic-waves-effects-discrete-wave-emission-high-wave-amplitudes"><span>Relativistic electron scattering by magnetosonic <span class="hlt">waves</span>: Effects of discrete <span class="hlt">wave</span> emission and high <span class="hlt">wave</span> amplitudes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Artemyev, A. V., E-mail: ante0226@gmail.com; Mourenas, D.; Krasnoselskikh, V. V.</p> <p>2015-06-15</p> <p>In this paper, we study relativistic electron scattering by fast magnetosonic <span class="hlt">waves</span>. We compare results of test particle simulations and the quasi-linear theory for different spectra of <span class="hlt">waves</span> to investigate how a fine structure of the <span class="hlt">wave</span> emission can influence electron resonant scattering. We show that for a realistically wide distribution of <span class="hlt">wave</span> normal angles θ (i.e., when the dispersion δθ≥0.5{sup °}), relativistic electron scattering is similar for a wide <span class="hlt">wave</span> spectrum and for a spectrum consisting in well-separated ion cyclotron harmonics. Comparisons of test particle simulations with quasi-linear theory show that for δθ>0.5{sup °}, the quasi-linear <span class="hlt">approximation</span> describes resonantmore » scattering correctly for a large enough plasma frequency. For a very narrow θ distribution (when δθ∼0.05{sup °}), however, the effect of a fine structure in the <span class="hlt">wave</span> spectrum becomes important. In this case, quasi-linear theory clearly fails in describing accurately electron scattering by fast magnetosonic <span class="hlt">waves</span>. We also study the effect of high <span class="hlt">wave</span> amplitudes on relativistic electron scattering. For typical conditions in the earth's radiation belts, the quasi-linear <span class="hlt">approximation</span> cannot accurately describe electron scattering for <span class="hlt">waves</span> with averaged amplitudes >300 pT. We discuss various applications of the obtained results for modeling electron dynamics in the radiation belts and in the Earth's magnetotail.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15857048','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15857048"><span>A full-<span class="hlt">wave</span> Helmholtz model for continuous-<span class="hlt">wave</span> ultrasound transmission.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huttunen, Tomi; Malinen, Matti; Kaipio, Jari P; White, Phillip Jason; Hynynen, Kullervo</p> <p>2005-03-01</p> <p>A full-<span class="hlt">wave</span> Helmholtz model of continuous-<span class="hlt">wave</span> (CW) ultrasound fields may offer several attractive features over widely used partial-<span class="hlt">wave</span> <span class="hlt">approximations</span>. For example, many full-<span class="hlt">wave</span> techniques can be easily adjusted for complex geometries, and multiple reflections of sound are automatically taken into account in the model. To date, however, the full-<span class="hlt">wave</span> modeling of CW fields in general 3D geometries has been avoided due to the large computational cost associated with the numerical <span class="hlt">approximation</span> of the Helmholtz equation. Recent developments in computing capacity together with improvements in finite element type modeling techniques are making possible <span class="hlt">wave</span> simulations in 3D geometries which reach over tens of wavelengths. The aim of this study is to investigate the feasibility of a full-<span class="hlt">wave</span> solution of the 3D Helmholtz equation for modeling of continuous-<span class="hlt">wave</span> ultrasound fields in an inhomogeneous medium. The numerical <span class="hlt">approximation</span> of the Helmholtz equation is computed using the ultraweak variational formulation (UWVF) method. In addition, an inverse problem technique is utilized to reconstruct the velocity distribution on the transducer which is used to model the sound source in the UWVF scheme. The modeling method is verified by comparing simulated and measured fields in the case of transmission of 531 kHz CW fields through layered plastic plates. The comparison shows a reasonable agreement between simulations and measurements at low angles of incidence but, due to mode conversion, the Helmholtz model becomes insufficient for simulating ultrasound fields in plates at large angles of incidence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014isms.confEWA01P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014isms.confEWA01P"><span>Broadband <span class="hlt">Rotational</span> Spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pate, Brooks</p> <p>2014-06-01</p> <p>The past decade has seen several major technology advances in electronics operating at microwave frequencies making it possible to develop a new generation of spectrometers for molecular <span class="hlt">rotational</span> spectroscopy. High-speed digital electronics, both arbitrary waveform generators and digitizers, continue on a Moore's Law-like development cycle that started around 1993 with device bandwidth doubling about every 36 months. These enabling technologies were the key to designing chirped-pulse Fourier transform microwave (CP-FTMW) spectrometers which offer significant sensitivity enhancements for broadband spectrum acquisition in molecular <span class="hlt">rotational</span> spectroscopy. A special feature of the chirped-pulse spectrometer design is that it is easily implemented at low frequency (below 8 GHz) where Balle-Flygare type spectrometers with Fabry-Perot cavity designs become technologically challenging due to the mirror size requirements. The capabilities of CP-FTMW spectrometers for studies of molecular structure will be illustrated by the collaborative research effort we have been a part of to determine the structures of water clusters - a project which has identified clusters up to the pentadecamer. A second technology trend that impacts molecular <span class="hlt">rotational</span> spectroscopy is the development of high power, solid state sources in the mm-<span class="hlt">wave</span>/THz regions. Results from the field of mm-<span class="hlt">wave</span> chirped-pulse Fourier transform spectroscopy will be described with an emphasis on new problems in chemical dynamics and analytical chemistry that these methods can tackle. The third (and potentially most important) technological trend is the reduction of microwave components to chip level using monolithic microwave integrated circuits (MMIC) - a technology driven by an enormous mass market in communications. Some recent advances in <span class="hlt">rotational</span> spectrometer designs that incorporate low-cost components will be highlighted. The challenge to the high-resolution spectroscopy community - as posed by Frank De</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3019092','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3019092"><span>Interaction between spiral and paced <span class="hlt">waves</span> in cardiac tissue</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Agladze, Konstantin; Kay, Matthew W.; Krinsky, Valentin; Sarvazyan, Narine</p> <p>2010-01-01</p> <p>For prevention of lethal arrhythmias, patients at risk receive implantable cardioverter-defibrillators, which use high-frequency antitachycardia pacing (ATP) to convert tachycardias to a normal rhythm. One of the suggested ATP mechanisms involves paced-induced drift of <span class="hlt">rotating</span> <span class="hlt">waves</span> followed by their collision with the boundary of excitable tissue. This study provides direct experimental evidence of this mechanism. In monolayers of neonatal rat cardiomyocytes in which <span class="hlt">rotating</span> <span class="hlt">waves</span> of activity were initiated by premature stimuli, we used the Ca2+-sensitive indicator fluo 4 to observe propagating <span class="hlt">wave</span> patterns. The interaction of the spiral tip with a paced <span class="hlt">wave</span> was then monitored at a high spatial resolution. In the course of the experiments, we observed spiral <span class="hlt">wave</span> pinning to local heterogeneities within the myocyte layer. High-frequency pacing led, in a majority of cases, to successful termination of spiral activity. Our data show that 1) stable spiral <span class="hlt">waves</span> in cardiac monolayers tend to be pinned to local heterogeneities or areas of altered conduction, 2) overdrive pacing can shift a <span class="hlt">rotating</span> <span class="hlt">wave</span> from its original site, and 3) the <span class="hlt">wave</span> break, formed as a result of interaction between the spiral tip and a paced <span class="hlt">wave</span> front, moves by a paced-induced drift mechanism to an area where it may become unstable or collide with a boundary. The data were complemented by numerical simulations, which was used to further analyze experimentally observed behavior. PMID:17384124</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5486292','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5486292"><span>Risk Assessment of Face Skin Exposure to UV Irradiance from Different <span class="hlt">Rotation</span> Angle Ranges</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wang, Fang; Gao, Qian; Deng, Yan; Chen, Rentong; Liu, Yang</p> <p>2017-01-01</p> <p>Ultraviolet (UV) is one of the environmental pathogenic factors causing skin damage. Aiming to assess the risk of face skin exposure to UV irradiance from different <span class="hlt">rotation</span> angles, a <span class="hlt">rotating</span> model was used to monitor the exposure of the skin on the face to UV irradiance, with skin damage action spectra used to determine the biologically effective UV irradiance (UVBEskin) and UVBEskin radiant exposure (HBEskin) causing skin damage. The results indicate that the UVBEskin is directly influenced by variations in <span class="hlt">rotation</span> angles. A significant decrease of <span class="hlt">approximately</span> 52.70% and 52.10% in UVBEskin was found when the cheek and nose measurement sites was <span class="hlt">rotated</span> from 0° to 90°, while a decrease of <span class="hlt">approximately</span> 62.70% was shown when the forehead measurement sites was <span class="hlt">rotated</span> from an angle of 0° to 108°. When HBEskin was compared to the exposure limits (ELs; 30 J·m−2), the maximum relative risk ratios (RR) for cheek, nose, and forehead were found to be <span class="hlt">approximately</span> 2.01, 2.40, and 2.90, respectively, which were all measured at a <span class="hlt">rotation</span> angle of 0°. The maximal increase in the percentage of the average HBEskin for <span class="hlt">rotation</span> angles of 60°, 120°, 180°, and 360° facing the sun to ELs were found to be <span class="hlt">approximately</span> 62.10%, 52.72%, 43.43%, and 26.27% for the cheek; <span class="hlt">approximately</span> 130.61%, 109.68%, 86.43%, and 50.06% for the nose; and <span class="hlt">approximately</span> 178.61%, 159.19%, 134.38%, and 83.41% for the forehead, respectively. PMID:28587318</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120014274','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120014274"><span>A Translational Polarization <span class="hlt">Rotator</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chuss, David T.; Wollack, Edward J.; Pisano, Giampaolo; Ackiss, Sheridan; U-Yen, Kongpop; Ng, Ming wah</p> <p>2012-01-01</p> <p>We explore a free-space polarization modulator in which a variable phase introduction between right- and left-handed circular polarization components is used to <span class="hlt">rotate</span> the linear polarization of the outgoing beam relative to that of the incoming beam. In this device, the polarization states are separated by a circular polarizer that consists of a quarter-<span class="hlt">wave</span> plate in combination with a wire grid. A movable mirror is positioned behind and parallel to the circular polarizer. As the polarizer-mirror distance is separated, an incident liear polarization will be <span class="hlt">rotated</span> through an angle that is proportional to the introduced phase delay. We demonstrate a prototype device that modulates Stokes Q and U over a 20% bandwidth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AAS...22913103N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AAS...22913103N"><span>The <span class="hlt">rotation</span>-activity relation in M dwarfs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Newton, Elisabeth R.; Irwin, Jonathan; Charbonneau, David; Berlind, Perry L.; Calkins, Michael L.; Mink, Jessica D.</p> <p>2017-01-01</p> <p>Main sequence stars with masses below <span class="hlt">approximately</span> 0.35 solar masses are fully-convective, and are expected to have a different type of magnetic dynamo than solar-type stars. Observationally, the dynamo mechanism can be probed through the relationship between <span class="hlt">rotation</span> and magnetic activity, and the evolution of these properties. Though M dwarfs are the most common type of star in the galaxy, a lack of observational constraints at ages beyond 1 Gyr has hampered studies of the <span class="hlt">rotation</span>-activity relation. To address this, we have made new measurements of <span class="hlt">rotation</span> and magnetic activity in nearby, field-age M dwarfs. Combining our 386 <span class="hlt">rotation</span> period measurements and 247 new optical spectra with data from the literature, we are able to probe the <span class="hlt">rotation</span>-activity in M dwarfs with masses from 0.1 to 0.6 solar masses. We observe a threshold in the mass--period plane that separates active and inactive M dwarfs. The threshold coincides with the fast-period edge of the slowly <span class="hlt">rotating</span> population, at <span class="hlt">approximately</span> the <span class="hlt">rotation</span> period at which an era of rapid <span class="hlt">rotational</span> evolution appears to cease. We confirm that the activity of rapidly <span class="hlt">rotating</span> M dwarfs maintains a saturated value. We have measured <span class="hlt">rotation</span> periods as long as 140 days, allowing us to probe the unsaturated regime in detail. Our data show a clear power-law decay in relative H-alpha luminosity as a function Rossby number. We discuss implications for the magnetic dynamo mechanism.We acknowledge funding from the National Science Foundation, the David and Lucile Packard Foundation Fellowship for Science and Engineering, and the John Templeton Foundation. E.R.N. acknowledges support from the NSF through a Graduate Research Fellowship and an Astronomy and Astrophysics Postdoctoral Fellowship.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28680691','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28680691"><span>Some aspects of an induced electric dipole moment in <span class="hlt">rotating</span> and non-<span class="hlt">rotating</span> frames.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Oliveira, Abinael B; Bakke, Knut</p> <p>2017-06-01</p> <p>Quantum effects on a neutral particle (atom or molecule) with an induced electric dipole moment are investigated when it is subject to the Kratzer potential and a scalar potential proportional to the radial distance. In addition, this neutral is placed in a region with electric and magnetic fields. This system is analysed in both non-<span class="hlt">rotating</span> and <span class="hlt">rotating</span> reference frames. Then, it is shown that bound state solutions to the Schrödinger equation can be achieved and, in the search for polynomial solutions to the radial <span class="hlt">wave</span> function, a restriction on the values of the cyclotron frequency is analysed in both reference frames.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG12A..04N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG12A..04N"><span>Torsional Alfvén <span class="hlt">Waves</span> in a Dipolar Magnetic Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nataf, H. C.; Tigrine, Z.; Cardin, P.; Schaeffer, N.</p> <p>2017-12-01</p> <p>The discovery of torsional Alfvén <span class="hlt">waves</span> in the Earth's core (Gillet et al, 2010) is a strong motivation for investigating the properties of these <span class="hlt">waves</span>. Here, we report on the first experimental study of such <span class="hlt">waves</span>. Alfvén <span class="hlt">waves</span> are difficult to excite and observe in liquid metals because of their high magnetic diffusivity. Nevertheless, we obtained clear signatures of such diffusive <span class="hlt">waves</span> in our DTS experiment. In this setup, some 40 liters of liquid sodium are contained between a ro = 210 mm-radius stainless steel outer shell, and a ri = 74 mm-radius copper inner sphere. Both spherical boundaries can <span class="hlt">rotate</span> independently around a common vertical axis. The inner sphere shells a strong permanent magnet, which produces a nearly dipolar magnetic field whose intensity falls from 175 mT at ri to 8 mT at ro in the equatorial plane. We excite Alfvén <span class="hlt">waves</span> in the liquid sodium by applying a sudden jerk of the inner sphere. To study the effect of global <span class="hlt">rotation</span>, which leads to the formation of geostrophic torsional Alfvén <span class="hlt">waves</span>, we spin the experiment at <span class="hlt">rotation</span> rates fo = fi up to 15 Hz. The Alfvén <span class="hlt">wave</span> produces a clear azimuthal magnetic signal on magnetometers installed in a sleeve inside the fluid. We also probe the associated azimuthal velocity field using ultrasound Doppler velocimetry. Electric potentials at the surface of the outer sphere turn out to be very revealing as well. In parallel, we use the XSHELLS magnetohydrodynamics spherical code to model torsional Alfvén <span class="hlt">waves</span> in the experimental conditions, and beyond. We explore both linear and non-linear regimes. We observe a strong excitation of inertial <span class="hlt">waves</span> in the equatorial plane, where the <span class="hlt">wave</span> transits from a region of strong magnetic field to a region dominated by <span class="hlt">rotation</span> (see figure of meridian map of azimuthal velocity). These novel observations should help deciphering the dynamics of Alfvén <span class="hlt">waves</span> in planetary cores.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900010628','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900010628"><span>Gravitational radiation from <span class="hlt">rotating</span> gravitational collapse</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stark, Richard F.</p> <p>1989-01-01</p> <p>The efficiency of gravitational <span class="hlt">wave</span> emission from axisymmetric <span class="hlt">rotating</span> collapse to a black hole was found to be very low: Delta E/Mc sq. less than 7 x 10(exp -4). The main waveform shape is well defined and nearly independent of the details of the collapse. Such a signature will allow pattern recognition techniques to be used when searching experimental data. These results (which can be scaled in mass) were obtained using a fully general relativistic computer code that evolves <span class="hlt">rotating</span> axisymmetric configurations and directly computes their gravitational radiation emission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OcMod.124...48E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OcMod.124...48E"><span>Bottom boundary layer forced by finite amplitude long and short surface <span class="hlt">waves</span> motions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Elsafty, H.; Lynett, P.</p> <p>2018-04-01</p> <p>A multiple-scale perturbation approach is implemented to solve the Navier-Stokes equations while including bottom boundary layer effects under a single <span class="hlt">wave</span> and under two interacting <span class="hlt">waves</span>. In this approach, fluid velocities and the pressure field are decomposed into two components: a potential component and a <span class="hlt">rotational</span> component. In this study, the two components are exist throughout the entire water column and each is scaled with appropriate length and time scales. A one-way coupling between the two components is implemented. The potential component is assumed to be known analytically or numerically a prior, and the <span class="hlt">rotational</span> component is forced by the potential component. Through order of magnitude analysis, it is found that the leading-order coupling between the two components occurs through the vertical convective acceleration. It is shown that this coupling plays an important role in the bottom boundary layer behavior. Its effect on the results is discussed for different <span class="hlt">wave</span>-forcing conditions: purely harmonic forcing and impurely harmonic forcing. The approach is then applied to derive the governing equations for the bottom boundary layer developed under two interacting <span class="hlt">wave</span> motions. Both motions-the shorter and the longer <span class="hlt">wave</span>-are decomposed into two components, potential and <span class="hlt">rotational</span>, as it is done in the single <span class="hlt">wave</span>. Test cases are presented wherein two different <span class="hlt">wave</span> forcings are simulated: (1) two periodic oscillatory motions and (2) short <span class="hlt">waves</span> interacting with a solitary <span class="hlt">wave</span>. The analysis of the two periodic motions indicates that nonlinear effects in the <span class="hlt">rotational</span> solution may be significant even though nonlinear effects are negligible in the potential forcing. The local differences in the <span class="hlt">rotational</span> velocity due to the nonlinear vertical convection coupling term are found to be on the order of 30% of the maximum boundary layer velocity for the cases simulated in this paper. This difference is expected to increase with the increase in <span class="hlt">wave</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6990H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6990H"><span>Inertial modes and their transition to turbulence in a differentially <span class="hlt">rotating</span> spherical gap flow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hoff, Michael; Harlander, Uwe; Andrés Triana, Santiago; Egbers, Christoph</p> <p>2016-04-01</p> <p> dominant mode (l,m,ˆω) = (3,2,˜ 0.71) is increasing with increasing |Ro| until a critical Rossby number Rocrit. Accompanying with this is an increase of the zonal mean flow outside the tangent cylinder, leading to enhanced angular momentum transport. At the particular Rocrit, the <span class="hlt">wave</span> mode, and the entire flow, breaks up into smaller-scale turbulence [6], together with a strong increase of the zonal mean flow inside the tangent cylinder. We found that the critical Rossby number scales <span class="hlt">approximately</span> with E1/5. References [1] Aldridge, K. D.; Lumb, L. I. (1987): Inertial <span class="hlt">waves</span> identified in the Earth's fluid outer core. Nature 325 (6103), S. 421-423. DOI: 10.1038/325421a0. [2] Greenspan, H. P. (1968): The theory of <span class="hlt">rotating</span> fluids. London: Cambridge U.P. (Cambridge monographs on mechanics and applied mathematics). [3] Kelley, D. H.; Triana, S. A.; Zimmerman, D. S.; Lathrop, D. P. (2010): Selection of inertial modes in spherical Couette flow. Phys. Rev. E 81 (2), 26311. DOI: 10.1103/PhysRevE.81.026311. [4] Rieutord, M.; Triana, S. A.; Zimmerman, D. S.; Lathrop, D. P. (2012): Excitation of inertial modes in an experimental spherical Couette flow. Phys. Rev. E 86 (2), 026304. DOI: 10.1103/PhysRevE.86.026304. [5] Hoff, M., Harlander, U., Egbers, C. (2016): Experimental survey of linear and nonlinear inertial <span class="hlt">waves</span> and <span class="hlt">wave</span> instabilities in a spherical shell. J. Fluid Mech., (in print) [6] Kerswell, R. R. (1999): Secondary instabilities in rapidly <span class="hlt">rotating</span> fluids: inertial <span class="hlt">wave</span> breakdown. Journal of Fluid Mechanics 382, S. 283-306. DOI: 10.1017/S0022112098003954.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17783836','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17783836"><span>Plasma <span class="hlt">waves</span> near saturn: initial results from voyager 1.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gurnett, D A; Kurth, W S; Scarf, F L</p> <p>1981-04-10</p> <p>The Voyager 1 plasma <span class="hlt">wave</span> instrument detected many familiar types of plasma <span class="hlt">waves</span> during the encounter with Saturn, including ion-acoustic <span class="hlt">waves</span> and electron plasma oscillations upstream of the bow shock, an intense burst of electrostatic noise at the shock, and chorus, hiss, electrostatic electron cyclotron <span class="hlt">waves</span>, and upper hybrid resonance emissions in the inner magnetosphere. A clocklike Saturn <span class="hlt">rotational</span> control of low-frequency radio emissions was observed, and evidence was obtained of possible control by the moon Dione. Strong plasma <span class="hlt">wave</span> emissions were detected at the Titan encounter indicating the presence of a turbulent sheath extending around Titan, and upper hybrid resonance measurements of the electron density show the existence of a dense plume of plasma being carried downstream of Titan by the interaction with the rapidly <span class="hlt">rotating</span> magnetosphere of Saturn.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7751E..1CS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7751E..1CS"><span>CARS measurement of vibrational and <span class="hlt">rotational</span> temperature with high power laser and high speed visualization of total radiation behind hypervelocity shock <span class="hlt">waves</span> of 5-7km/s</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sakurai, Kotaro; Bindu, Venigalla Hima; Niinomi, Shota; Ota, Masanori; Maeno, Kazuo</p> <p>2010-09-01</p> <p>Coherent Anti-Stokes Raman Spectroscopy (CARS) method is commonly used for measuring molecular structure or condition. In the aerospace technology, this method is applies to measure the temperature in thermic fluid with relatively long time duration of millisecond or sub millisecond. On the other hand, vibrational/<span class="hlt">rotational</span> temperatures behind hypervelocity shock <span class="hlt">wave</span> are important for heat-shield design in phase of reentry flight. The non-equilibrium flow with radiative heating from strongly shocked air ahead of the vehicles plays an important role on the heat flux to the wall surface structure as well as convective heating. In this paper CARS method is applied to measure the vibrational/<span class="hlt">rotational</span> temperature of N2 behind hypervelocity shock <span class="hlt">wave</span>. The strong shock <span class="hlt">wave</span> in front of the reentering space vehicles can be experimentally realigned by free-piston, double-diaphragm shock tube with low density test gas. However CARS measurement is difficult for our experiment. Our measurement needs very short pulse which order of nanosecond and high power laser for CARS method. It is due to our measurement object is the momentary phenomena which velocity is 7km/s. In addition the observation section is low density test gas, and there is the strong background light behind the shock <span class="hlt">wave</span>. So we employ the CARS method with high power, order of 1J/pulse, and very short pulse (10ns) laser. By using this laser the CARS signal can be acquired even in the strong radiation area. Also we simultaneously try to use the CCD camera to obtain total radiation with CARS method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1393232','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1393232"><span>Performance of a continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate on the POLARBEAR telescope</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki</p> <p></p> <p>A continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I, Q and U, thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-<span class="hlt">wave</span> plate diameter of ~0.5 m), where the CRHWP can be placed between the primary mirror and focalmore » plane. In this configuration, one needs to address the intensity to polarization (I→P) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the {\\scshape Polarbear} experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I→P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ~ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1393232-performance-continuously-rotating-half-wave-plate-polarbear-telescope','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1393232-performance-continuously-rotating-half-wave-plate-polarbear-telescope"><span>Performance of a continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate on the POLARBEAR telescope</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki; ...</p> <p>2017-05-03</p> <p>A continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I, Q and U, thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-<span class="hlt">wave</span> plate diameter of ~0.5 m), where the CRHWP can be placed between the primary mirror and focalmore » plane. In this configuration, one needs to address the intensity to polarization (I→P) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the {\\scshape Polarbear} experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I→P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ~ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22676231-performance-continuously-rotating-half-wave-plate-polarbear-telescope','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22676231-performance-continuously-rotating-half-wave-plate-polarbear-telescope"><span>Performance of a continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate on the POLARBEAR telescope</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Takakura, Satoru; Aguilar, Mario; Akiba, Yoshiki</p> <p></p> <p>A continuously <span class="hlt">rotating</span> half-<span class="hlt">wave</span> plate (CRHWP) is a promising tool to improve the sensitivity to large angular scales in cosmic microwave background (CMB) polarization measurements. With a CRHWP, single detectors can measure three of the Stokes parameters, I , Q and U , thereby avoiding the set of systematic errors that can be introduced by mismatches in the properties of orthogonal detector pairs. We focus on the implementation of CRHWPs in large aperture telescopes (i.e. the primary mirror is larger than the current maximum half-<span class="hlt">wave</span> plate diameter of ∼0.5 m), where the CRHWP can be placed between the primary mirrormore » and focal plane. In this configuration, one needs to address the intensity to polarization ( I → P ) leakage of the optics, which becomes a source of 1/f noise and also causes differential gain systematics that arise from CMB temperature fluctuations. In this paper, we present the performance of a CRHWP installed in the (\\scshape Polarbear) experiment, which employs a Gregorian telescope with a 2.5 m primary illumination pattern. The CRHWP is placed near the prime focus between the primary and secondary mirrors. We find that the I → P leakage is larger than the expectation from the physical properties of our primary mirror, resulting in a 1/f knee of 100 mHz. The excess leakage could be due to imperfections in the detector system, i.e. detector non-linearity in the responsivity and time-constant. We demonstrate, however, that by subtracting the leakage correlated with the intensity signal, the 1/f noise knee frequency is reduced to 32 mHz (ℓ ∼ 39 for our scan strategy), which is very promising to probe the primordial B-mode signal. We also discuss methods for further noise subtraction in future projects where the precise temperature control of instrumental components and the leakage reduction will play a key role.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1399502-dipole-approximation-predict-resonances-dimers-composed-dielectric-resonators-directional-emission-dielectric-dimers-dipole-approximation','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1399502-dipole-approximation-predict-resonances-dimers-composed-dielectric-resonators-directional-emission-dielectric-dimers-dipole-approximation"><span>Dipole <span class="hlt">Approximation</span> to Predict the Resonances of Dimers Composed of Dielectric Resonators for Directional Emission: Dielectric Dimers Dipole <span class="hlt">Approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Campione, Salvatore; Warne, Larry K.; Basilio, Lorena I.</p> <p>2017-09-29</p> <p>In this paper we develop a fully-retarded, dipole <span class="hlt">approximation</span> model to estimate the effective polarizabilities of a dimer made of dielectric resonators. They are computed from the polarizabilities of the two resonators composing the dimer. We analyze the situation of full-cubes as well as split-cubes, which have been shown to exhibit overlapping electric and magnetic resonances. We compare the effective dimer polarizabilities to ones retrieved via full-<span class="hlt">wave</span> simulations as well as ones computed via a quasi-static, dipole <span class="hlt">approximation</span>. We observe good agreement between the fully-retarded solution and the full-<span class="hlt">wave</span> results, whereas the quasi-static <span class="hlt">approximation</span> is less accurate for the problemmore » at hand. The developed model can be used to predict the electric and magnetic resonances of a dimer under parallel or orthogonal (to the dimer axis) excitation. This is particularly helpful when interested in locating frequencies at which the dimer will emit directional radiation.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23679540','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23679540"><span>Exact relativistic expressions for <span class="hlt">wave</span> refraction in a generally moving fluid.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cavalleri, G; Tonni, E; Barbero, F</p> <p>2013-04-01</p> <p>The law for the refraction of a <span class="hlt">wave</span> when the two fluids and the interface are moving with relativistic velocities is given in an exact form, at the same time correcting a first order error in a previous paper [Cavalleri and Tonni, Phys. Rev. E 57, 3478 (1998)]. The treatment is then extended to a generally moving fluid with variable refractive index, ready to be applied to the refraction of acoustic, electromagnetic, or magnetohydrodynamic <span class="hlt">waves</span> in the atmosphere of rapidly <span class="hlt">rotating</span> stars. In the particular case of a gas cloud receding because of the universe expansion, our result can be applied to predict observable micro- and mesolensings. The first order <span class="hlt">approximation</span> of our exact result for the deviation due to refraction of the light coming from a further quasar has a relativistic dependence equal to the one obtained by Einsteins' linearized theory of gravitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EPJP..132..501R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EPJP..132..501R"><span>Born distorted-<span class="hlt">wave</span> <span class="hlt">approximation</span> applied to the H+ + He collisions at intermediate and high energies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rahmanian, M.; Fathi, R.; Shojaei, F.</p> <p>2017-11-01</p> <p>The single-charge transfer process in collision of protons with helium atoms in their ground states is investigated. The model utilizes the second-order three-body Born distorted-<span class="hlt">wave</span> <span class="hlt">approximation</span> (BDW-3B) with correct Coulomb boundary conditions to calculate the differential and total cross sections at intermediate and high energies. The role of the passive electrons and electron-electron correlations are studied by comparing our results and the BDW-4B calculations with the complete perturbation potential. The present results are also compared with other theories, and the Thomas scattering mechanism is investigated. The obtained results are also compared with the recent experimental measurements. For the prior differential cross sections, the comparisons show better agreement with the experiments at smaller scattering angles. The agreement between the total cross sections and the BDW-4B results as well as the experimental data is good at higher impact energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890005051&hterms=Acoustic+levitation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DAcoustic%2Blevitation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890005051&hterms=Acoustic+levitation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DAcoustic%2Blevitation"><span>Controlled sample orientation and <span class="hlt">rotation</span> in an acoustic levitator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barmatz, Martin B. (Inventor); Gaspar, Mark S. (Inventor); Trinh, Eugene H. (Inventor)</p> <p>1988-01-01</p> <p>A system is described for use with acoustic levitators, which can prevent <span class="hlt">rotation</span> of a levitated object or control its orientation and/or <span class="hlt">rotation</span>. The acoustic field is made nonsymmetrical about the axis of the levitator, to produce an orienting torque that resists sample <span class="hlt">rotation</span>. In one system, a perturbating reflector is located on one side of the axis of the levitator, at a location near the levitated object. In another system, the main reflector surface towards which incoming acoustic <span class="hlt">waves</span> are directed is nonsymmetrically curved about the axis of the levitator. The levitated object can be reoriented or <span class="hlt">rotated</span> in a controlled manner by repositioning the reflector producing the nonsymmetry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150004119','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150004119"><span>Survey of Coherent <span class="hlt">Approximately</span> 1 Hz <span class="hlt">Waves</span> in Mercury's Inner Magnetosphere from MESSENGER Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Boardsen, Scott A.; Slavin, James A.; Anderson, Brian J.; Korth, Haje; Schriver, David; Solomon, Sean C.</p> <p>2012-01-01</p> <p>We summarize observations by the MESSENGER spacecraft of highly coherent <span class="hlt">waves</span> at frequencies between 0.4 and 5 Hz in Mercury's inner magnetosphere. This survey covers the time period from 24 March to 25 September 2011, or 2.1 Mercury years. These <span class="hlt">waves</span> typically exhibit banded harmonic structure that drifts in frequency as the spacecraft traverses the magnetic equator. The <span class="hlt">waves</span> are seen at all magnetic local times, but their observed rate of occurrence is much less on the dayside, at least in part the result of MESSENGER's orbit. On the nightside, on average, <span class="hlt">wave</span> power is maximum near the equator and decreases with increasing magnetic latitude, consistent with an equatorial source. When the spacecraft traverses the plasma sheet during its equatorial crossings, <span class="hlt">wave</span> power is a factor of 2 larger than for equatorial crossings that do not cross the plasma sheet. The <span class="hlt">waves</span> are highly transverse at large magnetic latitudes but are more compressional near the equator. However, at the equator the transverse component of these <span class="hlt">waves</span> increases relative to the compressional component as the degree of polarization decreases. Also, there is a substantial minority of events that are transverse at all magnetic latitudes, including the equator. A few of these latter events could be interpreted as ion cyclotron <span class="hlt">waves</span>. In general, the <span class="hlt">waves</span> tend to be strongly linear and characterized by values of the ellipticity less than 0.3 and <span class="hlt">wave</span>-normal angles peaked near 90 deg. Their maxima in <span class="hlt">wave</span> power at the equator coupled with their narrow-band character suggests that these <span class="hlt">waves</span> might be generated locally in loss cone plasma characterized by high values of the ratio beta of plasma pressure to magnetic pressure. Presumably both electromagnetic ion cyclotron <span class="hlt">waves</span> and electromagnetic ion Bernstein <span class="hlt">waves</span> can be generated by ion loss cone distributions. If proton beta decreases with increasing magnetic latitude along a field line, then electromagnetic ion Bernstein <span class="hlt">waves</span> are predicted</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28587318','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28587318"><span>Risk Assessment of Face Skin Exposure to UV Irradiance from Different <span class="hlt">Rotation</span> Angle Ranges.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Fang; Gao, Qian; Deng, Yan; Chen, Rentong; Liu, Yang</p> <p>2017-06-06</p> <p>Ultraviolet (UV) is one of the environmental pathogenic factors causing skin damage. Aiming to assess the risk of face skin exposure to UV irradiance from different <span class="hlt">rotation</span> angles, a <span class="hlt">rotating</span> model was used to monitor the exposure of the skin on the face to UV irradiance, with skin damage action spectra used to determine the biologically effective UV irradiance (UVBE skin ) and UVBE skin radiant exposure (HBE skin ) causing skin damage. The results indicate that the UVBE skin is directly influenced by variations in <span class="hlt">rotation</span> angles. A significant decrease of <span class="hlt">approximately</span> 52.70% and 52.10% in UVBE skin was found when the cheek and nose measurement sites was <span class="hlt">rotated</span> from 0° to 90°, while a decrease of <span class="hlt">approximately</span> 62.70% was shown when the forehead measurement sites was <span class="hlt">rotated</span> from an angle of 0° to 108°. When HBE skin was compared to the exposure limits (ELs; 30 J·m -2 ), the maximum relative risk ratios (RR) for cheek, nose, and forehead were found to be <span class="hlt">approximately</span> 2.01, 2.40, and 2.90, respectively, which were all measured at a <span class="hlt">rotation</span> angle of 0°. The maximal increase in the percentage of the average HBE skin for <span class="hlt">rotation</span> angles of 60°, 120°, 180°, and 360° facing the sun to ELs were found to be <span class="hlt">approximately</span> 62.10%, 52.72%, 43.43%, and 26.27% for the cheek; <span class="hlt">approximately</span> 130.61%, 109.68%, 86.43%, and 50.06% for the nose; and <span class="hlt">approximately</span> 178.61%, 159.19%, 134.38%, and 83.41% for the forehead, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750048814&hterms=liquid+soap&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dliquid%2Bsoap','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750048814&hterms=liquid+soap&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dliquid%2Bsoap"><span>Studies of <span class="hlt">rotating</span> liquid floating zones on Skylab IV</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carruthers, J. R.; Gibson, E. G.; Klett, M. G.; Facemire, B. R.</p> <p>1975-01-01</p> <p>Liquid zones of water, soap solution and soap foam were deployed between two aligned circular disks which were free to <span class="hlt">rotate</span> about the zone axis in the microgravity environment of Skylab IV. Such a configuration is of interest in the containerless handling of melts for possible future space processing crystal growth experiments. Three basic types of zone surface deformation and instability were observed for these <span class="hlt">rotational</span> conditions; axisymmetric shape changes under single disk <span class="hlt">rotation</span>, nonaxisymmetric, whirling, C-modes for long zones with equal <span class="hlt">rotation</span> of both disks, and capillary <span class="hlt">wave</span> phenomena for short zones with equal <span class="hlt">rotation</span> of both disks. The sources of these instabilities and the conditions promoting them are analyzed in detail from video tape recordings of the Skylab experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930066042&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcentrifugal%2Bcompressor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930066042&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcentrifugal%2Bcompressor"><span>A model for the selective amplification of spatially coherent <span class="hlt">waves</span> in a centrifugal compressor on the verge of <span class="hlt">rotating</span> stall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lawless, Patrick B.; Fleeter, Sanford</p> <p>1993-01-01</p> <p>A simple model for the stability zones of a low speed centrifugal compressor is developed, with the goal of understanding the driving mechanism for the changes in stalling behavior predicted for, and observed in, the Purdue Low Speed Centrifugal Research Compressor Facility. To this end, earlier analyses of <span class="hlt">rotating</span> stall suppression in centrifugal compressors are presented in a reduced form that preserves the essential parameters of the model that affect the stalling behavior of the compressor. The model is then used to illuminate the relationship between compressor geometry, expected mode shape, and regions of amplification for weak <span class="hlt">waves</span> which are indicative of the susceptibility of the system to <span class="hlt">rotating</span> stall. The results demonstrate that increasing the stagger angle of the diffuser vanes, and consequently the diffusion path length, results in the compressor moving towards a condition where higher-order spatial modes are excited during stall initiation. Similarly, flow acceleration in the diffuser section caused by an increase in the number of diffuser vanes also results in the excitation of higher modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JAP...120x5102S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JAP...120x5102S"><span>Planar composite chiral metamaterial with broadband dispersionless polarization <span class="hlt">rotation</span> and high transmission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Kun; Ding, Changlin; Su, Zhaoxian; Liu, Yahong; Luo, Chunrong; Zhao, Xiaopeng; Bhattarai, Khagendra; Zhou, Jiangfeng</p> <p>2016-12-01</p> <p>We propose a planar composite chiral metamaterial (CCMM) by symmetrically inserting a metallic mesh between two layers of conjugated gammadion resonators. As the elaborate CCMM operates at off-resonance frequencies, it therefore presents low-loss and low-dispersion polarization <span class="hlt">rotation</span> features. The results show that the proposed CCMM can achieve pure and dispersionless polarization <span class="hlt">rotation</span> with efficient transmission for a linearly polarized <span class="hlt">wave</span> within a broad bandwidth. This off-resonance CCMM overcomes the drawbacks of high transmission losses and highly dispersive polarization <span class="hlt">rotation</span> that exist in the previous resonance-type chiral metamaterials and also exhibits more simplicity of fabrication than the three-dimensional CMMs. The intriguing properties greatly improve the performance of chiral metamaterials in controlling the polarization state of electromagnetic <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20005557-solitary-wave-solutions-benjamin-equation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20005557-solitary-wave-solutions-benjamin-equation"><span>Solitary-<span class="hlt">wave</span> solutions of the Benjamin equation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Albert, J.P.; Bona, J.L.; Restrepo, J.M.</p> <p>1999-10-01</p> <p>Considered here is a model equation put forward by Benjamin that governs <span class="hlt">approximately</span> the evolution of <span class="hlt">waves</span> on the interface of a two-fluid system in which surface-tension effects cannot be ignored. The principal focus is the traveling-<span class="hlt">wave</span> solutions called solitary <span class="hlt">waves</span>, and three aspects will be investigated. A constructive proof of the existence of these <span class="hlt">waves</span> together with a proof of their stability is developed. Continuation methods are used to generate a scheme capable of numerically <span class="hlt">approximating</span> these solitary <span class="hlt">waves</span>. The computer-generated <span class="hlt">approximations</span> reveal detailed aspects of the structure of these <span class="hlt">waves</span>. They are symmetric about their crests, but unlikemore » the classical Korteqeg-de Vries solitary <span class="hlt">waves</span>, they feature a finite number of oscillations. The derivation of the equation is also revisited to get an idea of whether or not these oscillatory <span class="hlt">waves</span> might actually occur in a natural setting.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDG26008G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDG26008G"><span>Analysis of Porous Media as Inlet Concept for <span class="hlt">Rotating</span> Detonation Engines</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grogan, Kevin; Ihme, Matthias; Department of Mechanical Engineering Team</p> <p>2016-11-01</p> <p><span class="hlt">Rotating</span> detonation engines combust reactive gas mixtures with a high-speed, annularly-propagating detonation <span class="hlt">wave</span>, which provides many advantages including a stagnation pressure gain and a compact, lightweight design. However, the optimal design of the inlet to the combustion chamber inlet is a moot topic since improper design can significantly reduce detonability and increase pressure losses. The highly diffusive properties of porous media could make it an ideal material to prevent the flashback of the detonation <span class="hlt">wave</span> and therefore, allow the inlet gas to be premixed. Motivated by this potential, this work employs simulation to evaluate the application of porous media to the inlet of a <span class="hlt">rotating</span> detonation engine as a novel means to stabilize a detonation <span class="hlt">wave</span> while reducing the pressure losses incurred by non-ideal mixing strategies. Department of the Air Force.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvD..97f4042G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvD..97f4042G"><span>Extended I-Love relations for slowly <span class="hlt">rotating</span> neutron stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gagnon-Bischoff, Jérémie; Green, Stephen R.; Landry, Philippe; Ortiz, Néstor</p> <p>2018-03-01</p> <p>Observations of gravitational <span class="hlt">waves</span> from inspiralling neutron star binaries—such as GW170817—can be used to constrain the nuclear equation of state by placing bounds on stellar tidal deformability. For slowly <span class="hlt">rotating</span> neutron stars, the response to a weak quadrupolar tidal field is characterized by four internal-structure-dependent constants called "Love numbers." The tidal Love numbers k2el and k2mag measure the tides raised by the gravitoelectric and gravitomagnetic components of the applied field, and the <span class="hlt">rotational</span>-tidal Love numbers fo and ko measure those raised by couplings between the applied field and the neutron star spin. In this work, we compute these four Love numbers for perfect fluid neutron stars with realistic equations of state. We discover (nearly) equation-of-state independent relations between the <span class="hlt">rotational</span>-tidal Love numbers and the moment of inertia, thereby extending the scope of I-Love-Q universality. We find that similar relations hold among the tidal and <span class="hlt">rotational</span>-tidal Love numbers. These relations extend the applications of I-Love universality in gravitational-<span class="hlt">wave</span> astronomy. As our findings differ from those reported in the literature, we derive general formulas for the <span class="hlt">rotational</span>-tidal Love numbers in post-Newtonian theory and confirm numerically that they agree with our general-relativistic computations in the weak-field limit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PhRvD..84b4022G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PhRvD..84b4022G"><span>Collapse of differentially <span class="hlt">rotating</span> neutron stars and cosmic censorship</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giacomazzo, Bruno; Rezzolla, Luciano; Stergioulas, Nikolaos</p> <p>2011-07-01</p> <p>We present new results on the dynamics and gravitational-<span class="hlt">wave</span> emission from the collapse of differentially <span class="hlt">rotating</span> neutron stars. We have considered a number of polytropic stellar models having different values of the dimensionless angular momentum J/M2, where J and M are the asymptotic angular momentum and mass of the star, respectively. For neutron stars with J/M2<1, i.e. “sub-Kerr” models, we were able to find models that are dynamically unstable and that collapse promptly to a <span class="hlt">rotating</span> black hole. Both the dynamics of the collapse and the consequent emission of gravitational <span class="hlt">waves</span> resemble those seen for uniformly <span class="hlt">rotating</span> stars, although with an overall decrease in the efficiency of gravitational-<span class="hlt">wave</span> emission. For stellar models with J/M2>1, i.e. “supra-Kerr” models, on the other hand, we were not able to find models that are dynamically unstable and all of the computed supra-Kerr models were found to be far from the stability threshold. For these models a gravitational collapse is possible only after a very severe and artificial reduction of the pressure, which then leads to a torus developing nonaxisymmetric instabilities and eventually contracting to a stable axisymmetric stellar configuration. While this does not exclude the possibility that a naked singularity can be produced by the collapse of a differentially <span class="hlt">rotating</span> star, it also suggests that cosmic censorship is not violated and that generic conditions for a supra-Kerr progenitor do not lead to a naked singularity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16711925','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16711925"><span>Effect of heat flux on differential <span class="hlt">rotation</span> in turbulent convection.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kleeorin, Nathan; Rogachevskii, Igor</p> <p>2006-04-01</p> <p>We studied the effect of the turbulent heat flux on the Reynolds stresses in a <span class="hlt">rotating</span> turbulent convection. To this end we solved a coupled system of dynamical equations which includes the equations for the Reynolds stresses, the entropy fluctuations, and the turbulent heat flux. We used a spectral tau <span class="hlt">approximation</span> in order to close the system of dynamical equations. We found that the ratio of the contributions to the Reynolds stresses caused by the turbulent heat flux and the anisotropic eddy viscosity is of the order of <span class="hlt">approximately</span> 10(L rho/l0)2, where l0 is the maximum scale of turbulent motions and L rho is the fluid density variation scale. This effect is crucial for the formation of the differential <span class="hlt">rotation</span> and should be taken into account in the theories of the differential <span class="hlt">rotation</span> of the Sun, stars, and planets. In particular, we demonstrated that this effect may cause the differential <span class="hlt">rotation</span> which is comparable with the typical solar differential <span class="hlt">rotation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhFl...18h3103C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhFl...18h3103C"><span>Viscoelastic flow in <span class="hlt">rotating</span> curved pipes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Yitung; Chen, Huajun; Zhang, Jinsuo; Zhang, Benzhao</p> <p>2006-08-01</p> <p>Fully developed viscoelastic flows in <span class="hlt">rotating</span> curved pipes with circular cross section are investigated theoretically and numerically employing the Oldroyd-B fluid model. Based on Dean's <span class="hlt">approximation</span>, a perturbation solution up to the secondary order is obtained. The governing equations are also solved numerically by the finite volume method. The theoretical and numerical solutions agree with each other very well. The results indicate that the <span class="hlt">rotation</span>, as well as the curvature and elasticity, plays an important role in affecting the friction factor, the secondary flow pattern and intensity. The co-<span class="hlt">rotation</span> enhances effects of curvature and elasticity on the secondary flow. For the counter-<span class="hlt">rotation</span>, there is a critical <span class="hlt">rotational</span> number RΩ', which can make the effect of <span class="hlt">rotation</span> counteract the effect of curvature and elasticity. Complicated flow behaviors are found at this value. For the relative creeping flow, RΩ' can be estimated according to the expression RΩ'=-4Weδ. Effects of curvature and elasticity at different <span class="hlt">rotational</span> numbers on both relative creeping flow and inertial flow are also analyzed and discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017isms.confEWK11B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017isms.confEWK11B"><span>The Pure <span class="hlt">Rotational</span> Spectrum of KO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burton, Mark; Russ, Benjamin; Sheridan, Phillip M.; Bucchino, Matthew; Ziurys, Lucy M.</p> <p>2017-06-01</p> <p>The pure <span class="hlt">rotational</span> spectrum of potassium monoxide (KO) has been recorded using millimeter-<span class="hlt">wave</span> direct absorption spectroscopy. KO was synthesized by the reaction of potassium vapor, produced in a Broida-type oven, with nitrous oxide. No DC discharge was necessary. Eleven <span class="hlt">rotational</span> transitions belonging to the ^{2}Π_{3/2} spin-orbit component have been measured and have been fit successfully to a case (c) Hamiltonian. <span class="hlt">Rotational</span> and lambda-doubling constants for this spin-orbit component have been determined. It has been suggested that the ground electronic state of KO is either ^{2}Π (as for LiO and NaO) or ^{2}Σ (as for RbO and CsO), both of which lie close in energy. Recent computational studies favor a ^{2}Σ ground state. Further measurements of the <span class="hlt">rotational</span> transitions of the ^{2}Π_{1/2} spin-orbit component and the ^{2}Σ state are currently in progress, as well as the potassium hyperfine structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730032629&hterms=attention+span&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dattention%2Bspan','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730032629&hterms=attention+span&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dattention%2Bspan"><span>Venus - Atmospheric <span class="hlt">rotation</span>.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scott, A. H.; Reese, E. J.</p> <p>1972-01-01</p> <p>Photographs of Venus taken in ultraviolet light from Sept. 29, 1963, to May 29, 1971, indicate a general planet-wide circulation in the upper atmosphere of that planet having velocities which varied with time from -87 to -127m/sec at the equator. Positional measurements on 67 pairs of photographs which show the recurrence of similar patterns after intervals of one to three <span class="hlt">rotations</span> suggest an asymmetric bimodal distribution of these velocities. The ultraviolet markings appear to be randomly distributed and quite ephemeral in nature, rarely enduring in a recognizable pattern for more than 20 days and usually much less. Attention is directed to an apparent but fictitious mean sidereal <span class="hlt">rotation</span> period of <span class="hlt">approximately</span> 4.06 days derived from observations which are made at a single station and span many months or years. Under such conditions this fictitious value for the <span class="hlt">rotation</span> period is produced by the commensurability of the one-day period of earth and the assumed four-day period of the atmosphere of Venus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70155525','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70155525"><span>Modeled changes in extreme <span class="hlt">wave</span> climates of the tropical Pacific over the 21st century: Implications for U.S. and U.S.-Affiliated atoll islands</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shope, J.B.; Storlazzi, Curt; Erikson, Li H.; Hegermiller, C.A.</p> <p>2015-01-01</p> <p><span class="hlt">Wave</span> heights, periods, and directions were forecast for 2081–2100 using output from four coupled atmosphere–ocean global climate models for representative concentration pathway scenarios RCP4.5 and RCP8.5. Global climate model wind fields were used to drive the global WAVEWATCH-III <span class="hlt">wave</span> model to generate hourly time-series of bulk <span class="hlt">wave</span> parameters for 25 islands in the mid to western tropical Pacific. December–February 95th percentile extreme significant <span class="hlt">wave</span> heights under both climate scenarios decreased by 2100 compared to 1976–2010 historical values. Trends under both scenarios were similar, with the higher-emission RCP8.5 scenario displaying a greater decrease in extreme significant <span class="hlt">wave</span> heights than where emissions are reduced in the RCP4.5 scenario. Central equatorial Pacific Islands displayed the greatest departure from historical values; significant <span class="hlt">wave</span> heights decreased there by as much as 0.32 m during December–February and associated <span class="hlt">wave</span> directions <span class="hlt">rotated</span> <span class="hlt">approximately</span> 30° clockwise during June–August compared to hindcast data.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870017368&hterms=wave+oscillation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwave%2Boscillation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870017368&hterms=wave+oscillation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dwave%2Boscillation"><span>Steepened magnetosonic <span class="hlt">waves</span> in the high beta plasma surrounding Comet Giacobini-Zinner</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tsurutani, B. T.; Smith, E. J.; Thorne, R. M.; Gosling, J. T.; Matsumoto, H.</p> <p>1986-01-01</p> <p>Studies of intense hydromagnetic <span class="hlt">waves</span> at Giacobini-Zinner are extended to investigate the mode and direction of <span class="hlt">wave</span> propagation. Simultaneous high-resolution measurements of electron density fluctuations demonstrate that long period <span class="hlt">waves</span> propagate in the magnetosonic mode. Principal axis analyses of the long period <span class="hlt">waves</span> and accompanying partial <span class="hlt">rotations</span> show that the sum of the <span class="hlt">wave</span> phase <span class="hlt">rotations</span> is 360 deg, indicating that both are parts of the same <span class="hlt">wave</span> oscillation. The time sequence of the steepened waveforms observed by ICE shows that the <span class="hlt">waves</span> must propagate towards the Sun with Cph less than Vsw. Observations are consistent with <span class="hlt">wave</span> generation by resonant ion ring or ion beam instability which predicts right-hand polarized <span class="hlt">waves</span> propagating in the ion beam (solar) direction. The large amplitudes and small scale sizes of the cometary <span class="hlt">waves</span> suggest that rapid pitch-angle scattering and energy transfer with energetic ions should occur. Since the <span class="hlt">waves</span> are highly compressive, first-order Fermi acceleration is forecast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006MNRAS.372...53P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006MNRAS.372...53P"><span>Detecting a <span class="hlt">rotation</span> in the ɛ Eridani debris disc</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poulton, C. J.; Greaves, J. S.; Collier Cameron, A.</p> <p>2006-10-01</p> <p>The evidence for a <span class="hlt">rotation</span> of the ɛ Eridani debris disc is examined. Data at 850-μm wavelength were previously obtained using the Submillimetre Common User Bolometer Array (SCUBA) over periods of 1997-1998 and 2000-2002. By χ2 fitting after shift and <span class="hlt">rotation</span> operations, images from these two epochs were compared to recover proper motion and orbital motion of the disc. The same procedures were then performed on simulated images to estimate the accuracy of the results. Minima in the χ2 plots indicate a motion of the disc of <span class="hlt">approximately</span> 0.6 arcsec per year in the direction of the star's proper motion. This underestimates the true value of 1 arcsec per year, implying that some of the structure in the disc region is not associated with ɛ Eridani, originating instead from background galaxies. From the χ2 fitting for orbital motion, a counterclockwise <span class="hlt">rotation</span> rate of per year is deduced. Comparisons with simulated data in which the disc is not <span class="hlt">rotating</span> show that noise and background galaxies result in <span class="hlt">approximately</span> Gaussian fluctuations with a standard deviation of per year. Thus, counterclockwise <span class="hlt">rotation</span> of disc features is supported at <span class="hlt">approximately</span> a 2σ level, after a 4-yr time difference. This rate is faster than the Keplerian rate of per year for features at ~65 au from the star, suggesting their motion is tracking a planet inside the dust ring. Future observations with SCUBA-2 can rule out no <span class="hlt">rotation</span> of the ɛ Eridani dust clumps with ~4σ confidence. Assuming a rate of about per year, the <span class="hlt">rotation</span> of the features after a 10-yr period could be shown to be >=1° per year at the 3σ level.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830044831&hterms=averaged+lagrangian&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Daveraged%2Blagrangian','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830044831&hterms=averaged+lagrangian&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Daveraged%2Blagrangian"><span>Microscopic Lagrangian description of warm plasmas. IV - Macroscopic <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kim, H.; Crawford, F. W.</p> <p>1983-01-01</p> <p>The averaged-Lagrangian method is applied to linear <span class="hlt">wave</span> propagation and nonlinear three-<span class="hlt">wave</span> interaction in a warm magnetoplasma, in the macroscopic <span class="hlt">approximation</span>. The microscopic Lagrangian treated by Kim and Crawford (1977) and by Galloway and Crawford (1977) is first expanded to third order in perturbation. Velocity integration is then carried out, before applying Hamilton's principle to obtain a general description of <span class="hlt">wave</span> propagation and coupling. The results are specialized to the case of interaction between two electron plasma <span class="hlt">waves</span> and an Alfven <span class="hlt">wave</span>. The method is shown to be more powerful than the alternative possibility of working from the beginning with a macroscopic Lagrangian density.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvE..96f2204D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvE..96f2204D"><span>Synchronization of coupled active <span class="hlt">rotators</span> by common noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dolmatova, Anastasiya V.; Goldobin, Denis S.; Pikovsky, Arkady</p> <p>2017-12-01</p> <p>We study the effect of common noise on coupled active <span class="hlt">rotators</span>. While such a noise always facilitates synchrony, coupling may be attractive (synchronizing) or repulsive (desynchronizing). We develop an analytical approach based on a transformation to <span class="hlt">approximate</span> angle-action variables and averaging over fast <span class="hlt">rotations</span>. For identical <span class="hlt">rotators</span>, we describe a transition from full to partial synchrony at a critical value of repulsive coupling. For nonidentical <span class="hlt">rotators</span>, the most nontrivial effect occurs at moderate repulsive coupling, where a juxtaposition of phase locking with frequency repulsion (anti-entrainment) is observed. We show that the frequency repulsion obeys a nontrivial power law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6448774-utility-cs-ios-approximations-calculating-generalized-phenomenological-cross-sections-atom-diatom-systems','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6448774-utility-cs-ios-approximations-calculating-generalized-phenomenological-cross-sections-atom-diatom-systems"><span>Utility of the CS and IOS <span class="hlt">approximations</span> for calculating generalized phenomenological cross sections in atom-diatom systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Fitz, D.E.; Kouri, D.J.; Liu, W.K.</p> <p>1982-04-01</p> <p>The calculation of shear viscosity and thermal conductivity coefficients in the presence of a magnetic field requires the accurate calculation of several types of generalized phenomenological cross sections in which velocity and angular momentum tensors are coupled with the orbital and <span class="hlt">rotational</span> motion of the system. These cross sections are then averaged over energy in a fashion appropriate for the phenomenon of interest. The coupled states (CS) and/or infinite order sudden (IOS) <span class="hlt">approximations</span> have been used to calculate several such cross sections for systems such as He-HCl, He-CO, He-H/sub 2/, HD-Ne, Ar-N/sub 2/, and Ne-H/sub 2/. Excellent results are obtainedmore » compared with close-coupled methods for cross sections which are symmetric in tensor index, especially in the CS <span class="hlt">approximation</span>, and these results are not very sensitive to the choice of orbital <span class="hlt">wave</span> parameter. On the other hand, the cross sections which are asymmetric in tensor index are much more sensitive to interference effects and are unsatisfactory in many cases.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvF...2d4003R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvF...2d4003R"><span>Hydrodynamic <span class="hlt">waves</span> in films flowing under an inclined plane</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rohlfs, Wilko; Pischke, Philipp; Scheid, Benoit</p> <p>2017-04-01</p> <p>This study addresses the fluid dynamics of two-dimensional falling films flowing underneath an inclined plane using the weighted integral boundary layer (WIBL) model and direct numerical simulations (DNSs). Film flows under an inclined plane are subject to hydrodynamic and Rayleigh-Taylor instabilities, leading to the formation of two- and three-dimensional <span class="hlt">waves</span>, rivulets, and eventually dripping. The latter can only occur in film flows underneath an inclined plane such that the gravitational force acts in a destabilizing manner by pulling liquid into the gaseous atmosphere. The DNSs are performed using the solver interFoam of the open-source code OpenFOAM with a gradient limiter approach that avoids artificial oversharpening of the interface. We find good agreement between the two model approaches for <span class="hlt">wave</span> amplitude and <span class="hlt">wave</span> speed irrespectively of the orientation of the gravitational force and before the onset of dripping. The latter cannot be modeled with the WIBL model by nature as it is a single-value model. However, for large-amplitude solitarylike <span class="hlt">waves</span>, the WIBL model fails to predict the velocity field within the <span class="hlt">wave</span>, which is confirmed by a balance of viscous dissipation and the change in potential energy. In the wavy film flows, different flow features can occur such as circulating <span class="hlt">waves</span>, i.e., circulating eddies in the main <span class="hlt">wave</span> hump, or flow reversal, i.e., <span class="hlt">rotating</span> vortices in the capillary minima of the <span class="hlt">wave</span>. A phase diagram for all flow features is presented based on results of the WIBL model. Regarding the transition to circulating <span class="hlt">waves</span>, we show that a critical ratio between the maximum and substrate film thickness (<span class="hlt">approximately</span> 2.5) is also universal for film flows underneath inclined planes (independent of wavelength, inclination, viscous dissipation, and Reynolds number).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990032567','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990032567"><span>Double Resonances and Spectral Scaling in the Weak Turbulence Theory of <span class="hlt">Rotating</span> and Stratified Turbulence</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rubinstein, Robert</p> <p>1999-01-01</p> <p>In <span class="hlt">rotating</span> turbulence, stably stratified turbulence, and in <span class="hlt">rotating</span> stratified turbulence, heuristic arguments concerning the turbulent time scale suggest that the inertial range energy spectrum scales as k(exp -2). From the viewpoint of weak turbulence theory, there are three possibilities which might invalidate these arguments: four-<span class="hlt">wave</span> interactions could dominate three-<span class="hlt">wave</span> interactions leading to a modified inertial range energy balance, double resonances could alter the time scale, and the energy flux integral might not converge. It is shown that although double resonances exist in all of these problems, they do not influence overall energy transfer. However, the resonance conditions cause the flux integral for <span class="hlt">rotating</span> turbulence to diverge logarithmically when evaluated for a k(exp -2) energy spectrum; therefore, this spectrum requires logarithmic corrections. Finally, the role of four-<span class="hlt">wave</span> interactions is briefly discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhPl...25e2109G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhPl...25e2109G"><span>Excitation of higher radial modes of azimuthal surface <span class="hlt">waves</span> in the electron cyclotron frequency range by <span class="hlt">rotating</span> relativistic flow of electrons in cylindrical waveguides partially filled by plasmas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Girka, Igor O.; Pavlenko, Ivan V.; Thumm, Manfred</p> <p>2018-05-01</p> <p>Azimuthal surface <span class="hlt">waves</span> are electromagnetic eigenwaves of cylindrical plasma-dielectric waveguides which propagate azimuthally nearby the plasma-dielectric interface across an axial external stationary magnetic field. Their eigenfrequency in particular can belong to the electron cyclotron frequency range. Excitation of azimuthal surface <span class="hlt">waves</span> by <span class="hlt">rotating</span> relativistic electron flows was studied in detail recently in the case of the zeroth radial mode for which the <span class="hlt">waves</span>' radial phase change within the layer where the electrons gyrate is small. In this case, just the plasma parameters cause the main influence on the <span class="hlt">waves</span>' dispersion properties. In the case of the first and higher radial modes, the <span class="hlt">wave</span> eigenfrequency is higher and the wavelength is shorter than in the case of the zeroth radial mode. This gain being of interest for practical applications can be achieved without any change in the device design. The possibility of effective excitation of the higher order radial modes of azimuthal surface <span class="hlt">waves</span> is demonstrated here. Getting shorter wavelengths of the excited <span class="hlt">waves</span> in the case of higher radial modes is shown to be accompanied by decreasing growth rates of the <span class="hlt">waves</span>. The results obtained here are of interest for developing new sources of electromagnetic radiation, in nano-physics and in medical physics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914121R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914121R"><span>Jet-front systems nearing strongly stratified region in differentially heated, <span class="hlt">rotating</span> stratified annulus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rolland, Joran; Achatz, Ulrich</p> <p>2017-04-01</p> <p>The differentially heated, <span class="hlt">rotating</span> annulus configuration has been used for a long time as a model system of the earth troposphere. It can easily reproduce thermal wind and baroclinic <span class="hlt">waves</span> in the laboratory. It has recently been shown numerically that provided the Rossby number, the <span class="hlt">rotation</span> rate and the Brunt-Väisälä frequency were well chosen, this configuration also reproduces the spontaneous emission of gravity <span class="hlt">waves</span> by jet front systems [1]. This offers a very practical configuration in which to study an important process of emission of atmospheric gravity <span class="hlt">waves</span>. It has also been shown experimentally that this configuration can be modified in order to add the possibility for the emitted <span class="hlt">wave</span> to reach a strongly stratified region [2]. It thus creates a system containing a model troposphere where gravity <span class="hlt">waves</span> are spontaneously emitted and can propagate to a model stratosphere. For this matter a stratification was created using a salinity gradient in the experimental apparatus. Through double diffusion, this generates a strongly stratified layer in the middle of the flow (the model stratosphere) and two weakly stratified region in the top and bottom layers (the model troposphere). In this poster, we present simulations of this configuration displaying baroclinic <span class="hlt">waves</span> in the top and bottom layers. We aim at creating jet front systems strong enough that gravity <span class="hlt">waves</span> can be spontaneously emitted. This will thus offer the possibility of studying the <span class="hlt">wave</span> characteristic and mechanisms in emission and propagation in details. References [1] S. Borchert, U. Achatz, M.D. Fruman, Spontaneous Gravity <span class="hlt">wave</span> emission in the differentially heated annulus, J. Fluid Mech. 758, 287-311 (2014). [2] M. Vincze, I. Borcia, U. Harlander, P. Le Gal, Double-diffusive convection convection and baroclinic instability in a differentially heated and initially stratified <span class="hlt">rotating</span> system: the barostrat instability, Fluid Dyn. Res. 48, 061414 (2016).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950053622&hterms=foreshock&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dforeshock','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950053622&hterms=foreshock&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dforeshock"><span>ULF <span class="hlt">waves</span> in the foreshock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Greenstadt, E. W.; Le, G.; Strangeway, R. J.</p> <p>1995-01-01</p> <p>We review our current knowledge of ULF <span class="hlt">waves</span> in planetary foreshocks. Most of this knowledge comes from observations taken within a few Earth radii of the terrestrial bow shock. Terrestrial foreshock ULF <span class="hlt">waves</span> can be divided into three types, large amplitude low frequency <span class="hlt">waves</span> (<span class="hlt">approximately</span> 30-s period), upstream propagating whistlers (1-Hz <span class="hlt">waves</span>), and 3-s <span class="hlt">waves</span>. The 30-s <span class="hlt">waves</span> are apparently generated by back-streaming ion beams, while the 1-Hz <span class="hlt">waves</span> are generated at the bow shock. The source of the 3-s <span class="hlt">waves</span> has yet to be determined. In addition to issues concerning the source of ULF <span class="hlt">waves</span> in the foreshock, the <span class="hlt">waves</span> present a number of challenges, both in terms of data acquisition, and comparison with theory. The various <span class="hlt">waves</span> have different coherence scales, from <span class="hlt">approximately</span> 100 km to <span class="hlt">approximately</span> 1 Earth radius. Thus multi-spacecraft separation strategies must be tailored to the phenomenon of interest. From a theoretical point of view, the ULF <span class="hlt">waves</span> are observed in a plasma in which the thermal pressure is comparable to the magnetic pressure, and the rest-frame <span class="hlt">wave</span> frequency can be moderate fraction of the proton gyro-frequency. This requires the use of kinetic plasma <span class="hlt">wave</span> dispersion relations, rather than multi-fluid MHD. Lastly, and perhaps most significantly, ULF <span class="hlt">waves</span> are used to probe the ambient plasma, with inferences being drawn concerning the types of energetic ion distributions within the foreshock. However, since most of the data were acquired close to the bow shock, the properties of the more distant foreshock have to be deduced mainly through extrapolation of the near-shock results. A general understanding of the <span class="hlt">wave</span> and plasma populations within the foreshock, their interrelation, and evolution, requires additional data from the more distant foreshock.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3071724','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3071724"><span>Scroll-<span class="hlt">Wave</span> Dynamics in Human Cardiac Tissue: Lessons from a Mathematical Model with Inhomogeneities and Fiber Architecture</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Majumder, Rupamanjari; Nayak, Alok Ranjan; Pandit, Rahul</p> <p>2011-01-01</p> <p>Cardiac arrhythmias, such as ventricular tachycardia (VT) and ventricular fibrillation (VF), are among the leading causes of death in the industrialized world. These are associated with the formation of spiral and scroll <span class="hlt">waves</span> of electrical activation in cardiac tissue; single spiral and scroll <span class="hlt">waves</span> are believed to be associated with VT whereas their turbulent analogs are associated with VF. Thus, the study of these <span class="hlt">waves</span> is an important biophysical problem. We present a systematic study of the combined effects of muscle-fiber <span class="hlt">rotation</span> and inhomogeneities on scroll-<span class="hlt">wave</span> dynamics in the TNNP (ten Tusscher Noble Noble Panfilov) model for human cardiac tissue. In particular, we use the three-dimensional TNNP model with fiber <span class="hlt">rotation</span> and consider both conduction and ionic inhomogeneities. We find that, in addition to displaying a sensitive dependence on the positions, sizes, and types of inhomogeneities, scroll-<span class="hlt">wave</span> dynamics also depends delicately upon the degree of fiber <span class="hlt">rotation</span>. We find that the tendency of scroll <span class="hlt">waves</span> to anchor to cylindrical conduction inhomogeneities increases with the radius of the inhomogeneity. Furthermore, the filament of the scroll <span class="hlt">wave</span> can exhibit drift or meandering, transmural bending, twisting, and break-up. If the scroll-<span class="hlt">wave</span> filament exhibits weak meandering, then there is a fine balance between the anchoring of this <span class="hlt">wave</span> at the inhomogeneity and a disruption of <span class="hlt">wave</span>-pinning by fiber <span class="hlt">rotation</span>. If this filament displays strong meandering, then again the anchoring is suppressed by fiber <span class="hlt">rotation</span>; also, the scroll <span class="hlt">wave</span> can be eliminated from most of the layers only to be regenerated by a seed <span class="hlt">wave</span>. Ionic inhomogeneities can also lead to an anchoring of the scroll <span class="hlt">wave</span>; scroll <span class="hlt">waves</span> can now enter the region inside an ionic inhomogeneity and can display a coexistence of spatiotemporal chaos and quasi-periodic behavior in different parts of the simulation domain. We discuss the experimental implications of our study. PMID:21483682</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1776i0049T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1776i0049T"><span><span class="hlt">Approximating</span> a nonlinear advanced-delayed equation from acoustics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Teodoro, M. Filomena</p> <p>2016-10-01</p> <p>We <span class="hlt">approximate</span> the solution of a particular non-linear mixed type functional differential equation from physiology, the mucosal <span class="hlt">wave</span> model of the vocal oscillation during phonation. The mathematical equation models a superficial <span class="hlt">wave</span> propagating through the tissues. The numerical scheme is adapted from the work presented in [1, 2, 3], using homotopy analysis method (HAM) to solve the non linear mixed type equation under study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17257345','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17257345"><span>The effect of the earth's <span class="hlt">rotation</span> on ground water motion.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Loáiciga, Hugo A</p> <p>2007-01-01</p> <p>The average pore velocity of ground water according to Darcy's law is a function of the fluid pressure gradient and the gravitational force (per unit volume of ground water) and of aquifer properties. There is also an acceleration exerted on ground water that arises from the Earth's <span class="hlt">rotation</span>. The magnitude and direction of this <span class="hlt">rotation</span>-induced force are determined in exact mathematical form in this article. It is calculated that the gravitational force is at least 300 times larger than the largest <span class="hlt">rotation</span>-induced force anywhere on Earth, the latter force being maximal along the equator and <span class="hlt">approximately</span> equal to 34 N/m(3) there. This compares with a gravitational force of <span class="hlt">approximately</span> 10(4) N/m(3).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810060806&hterms=surface+density&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsurface%2Bdensity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810060806&hterms=surface+density&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsurface%2Bdensity"><span>Density <span class="hlt">waves</span> in Saturn's rings</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cuzzi, J. N.; Lissauer, J. J.; Shu, F. H.</p> <p>1981-01-01</p> <p>Certain radial brightness variations in the outer Cassini division of Saturn's rings may be spiral density <span class="hlt">waves</span> driven by Saturn's large moon Iapetus, in which case a value of <span class="hlt">approximately</span> 16 g/sq cm for the surface density is calculated in the region where the <span class="hlt">waves</span> are seen. The kinematic viscosity in the same region is <span class="hlt">approximately</span> 170 sq cm/s and the vertical scale height of the ring is estimated to be a maximum of <span class="hlt">approximately</span> 40 m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22463311','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22463311"><span>Magnetized stratified <span class="hlt">rotating</span> shear <span class="hlt">waves</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Salhi, A; Lehner, T; Godeferd, F; Cambon, C</p> <p>2012-02-01</p> <p>We present a spectral linear analysis in terms of advected Fourier modes to describe the behavior of a fluid submitted to four constraints: shear (with rate S), <span class="hlt">rotation</span> (with angular velocity Ω), stratification, and magnetic field within the linear spectral theory or the shearing box model in astrophysics. As a consequence of the fact that the base flow must be a solution of the Euler-Boussinesq equations, only radial and/or vertical density gradients can be taken into account. Ertel's theorem no longer is valid to show the conservation of potential vorticity, in the presence of the Lorentz force, but a similar theorem can be applied to a potential magnetic induction: The scalar product of the density gradient by the magnetic field is a Lagrangian invariant for an inviscid and nondiffusive fluid. The linear system with a minimal number of solenoidal components, two for both velocity and magnetic disturbance fields, is eventually expressed as a four-component inhomogeneous linear differential system in which the buoyancy scalar is a combination of solenoidal components (variables) and the (constant) potential magnetic induction. We study the stability of such a system for both an infinite streamwise wavelength (k(1) = 0, axisymmetric disturbances) and a finite one (k(1) ≠ 0, nonaxisymmetric disturbances). In the former case (k(1) = 0), we recover and extend previous results characterizing the magnetorotational instability (MRI) for combined effects of radial and vertical magnetic fields and combined effects of radial and vertical density gradients. We derive an expression for the MRI growth rate in terms of the stratification strength, which indicates that purely radial stratification can inhibit the MRI instability, while purely vertical stratification cannot completely suppress the MRI instability. In the case of nonaxisymmetric disturbances (k(1) ≠ 0), we only consider the effect of vertical stratification, and we use Levinson's theorem to demonstrate the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4042S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4042S"><span>An event database for <span class="hlt">rotational</span> seismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salvermoser, Johannes; Hadziioannou, Celine; Hable, Sarah; Chow, Bryant; Krischer, Lion; Wassermann, Joachim; Igel, Heiner</p> <p>2016-04-01</p> <p>The ring laser sensor (G-ring) located at Wettzell, Germany, routinely observes earthquake-induced <span class="hlt">rotational</span> ground motions around a vertical axis since its installation in 2003. Here we present results from a recently installed event database which is the first that will provide ring laser event data in an open access format. Based on the GCMT event catalogue and some search criteria, seismograms from the ring laser and the collocated broadband seismometer are extracted and processed. The ObsPy-based processing scheme generates plots showing waveform fits between <span class="hlt">rotation</span> rate and transverse acceleration and extracts characteristic wavefield parameters such as peak ground motions, noise levels, Love <span class="hlt">wave</span> phase velocities and waveform coherence. For each event, these parameters are stored in a text file (json dictionary) which is easily readable and accessible on the website. The database contains >10000 events starting in 2007 (Mw>4.5). It is updated daily and therefore provides recent events at a time lag of max. 24 hours. The user interface allows to filter events for epoch, magnitude, and source area, whereupon the events are displayed on a zoomable world map. We investigate how well the <span class="hlt">rotational</span> motions are compatible with the expectations from the surface <span class="hlt">wave</span> magnitude scale. In addition, the website offers some python source code examples for downloading and processing the openly accessible waveforms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017A%26A...600A..44O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017A%26A...600A..44O"><span>Millimeter-<span class="hlt">wave</span> spectroscopy of hydantoin, a possible precursor of glycine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ozeki, Hiroyuki; Miyahara, Rio; Ihara, Hiroto; Todaka, Satoshi; Kobayashi, Kaori; Ohishi, Masatoshi</p> <p>2017-04-01</p> <p>Context. Hydantoin (Imidazolidine-2, 4-dione, C3H4N2O2) is a five-membered heterocyclic compound that is known to arise from prebiotic molecules such as glycolic acid and urea, and to give the simplest amino acid, glycine, by hydrolysis under acidic condition. The gas chromatography combined with the mass spectrometry of carbonaceous chondrites lead to the detection of this molecule as well as several kinds of amino acids. Aims: The lack of spectroscopic information, especially on the <span class="hlt">rotational</span> constants, has prevented us from conducting a search for hydantoin in interstellar space. If a <span class="hlt">rotational</span> temperature of 100 K is assumed as the kinetic temperature of a star-forming region, the spectral intensity is expected to be at its maximum in the millimeter-<span class="hlt">wave</span> region. Laboratory spectroscopy of hydantoin in the millimeter-<span class="hlt">wave</span> region is the most important in providing accurate rest frequencies to be used for astronomical research. Methods: Pure <span class="hlt">rotational</span> spectra of hydantoin were observed in the millimeter-<span class="hlt">wave</span> region using the frequency modulated microwave spectrometer at Toho University. Solid hydantoin was heated to around 150 °C to provide appropriate vapor pressure. Quantum chemical calculations suggest that the permanent dipole moment of this molecule lies almost along the b-molecular axis, so that spectral search for b-type R-branch transition has been conducted. Results: <span class="hlt">Rotational</span> and centrifugal distortion constants up to the fourth order for the ground vibrational state of hydantoin were accurately determined by measuring 161 b-type transitions in the frequency range between 90 and 370 GHz. In addition, we succeeded in assigning 230 satellite lines, which were attributed to the two vibrationally excited states. The spectral intensity ratio of these lines indicates that these states correspond to the low-lying (<span class="hlt">approximately</span> 150 cm-1 above the ground state) vibrational modes. Conclusions: The frequency catalog of hydantoin in the millimeter-<span class="hlt">wave</span> range</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016isms.confEMJ05E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016isms.confEMJ05E"><span>Chiral Analysis of Isopulegol by Fourier Transform Molecular <span class="hlt">Rotational</span> Spectroscopy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Evangelisti, Luca; Seifert, Nathan A.; Spada, Lorenzo; Pate, Brooks</p> <p>2016-06-01</p> <p>Chiral analysis on molecules with multiple chiral centers can be performed using pulsed-jet Fourier transform <span class="hlt">rotational</span> spectroscopy. This analysis includes quantitative measurement of diastereomer products and, with the three <span class="hlt">wave</span> mixing methods developed by Patterson, Schnell, and Doyle (Nature 497, 475-477 (2013)), quantitative determination of the enantiomeric excess of each diastereomer. The high resolution features enable to perform the analysis directly on complex samples without the need for chromatographic separation. Isopulegol has been chosen to show the capabilities of Fourier transform <span class="hlt">rotational</span> spectroscopy for chiral analysis. Broadband <span class="hlt">rotational</span> spectroscopy produces spectra with signal-to-noise ratio exceeding 1000:1. The ability to identify low-abundance (0.1-1%) diastereomers in the sample will be described. Methods to rapidly identify <span class="hlt">rotational</span> spectra from isotopologues at natural abundance will be shown and the molecular structures obtained from this analysis will be compared to theory. The role that quantum chemistry calculations play in identifying structural minima and estimating their spectroscopic properties to aid spectral analysis will be described. Finally, the implementation of three <span class="hlt">wave</span> mixing techniques to measure the enantiomeric excess of each diastereomer and determine the absolute configuration of the enantiomer in excess will be described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..APR.L1045A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..APR.L1045A"><span>Comparing numerical and analytic <span class="hlt">approximate</span> gravitational waveforms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Afshari, Nousha; Lovelace, Geoffrey; SXS Collaboration</p> <p>2016-03-01</p> <p>A direct observation of gravitational <span class="hlt">waves</span> will test Einstein's theory of general relativity under the most extreme conditions. The Laser Interferometer Gravitational-<span class="hlt">Wave</span> Observatory, or LIGO, began searching for gravitational <span class="hlt">waves</span> in September 2015 with three times the sensitivity of initial LIGO. To help Advanced LIGO detect as many gravitational <span class="hlt">waves</span> as possible, a major research effort is underway to accurately predict the expected <span class="hlt">waves</span>. In this poster, I will explore how the gravitational waveform produced by a long binary-black-hole inspiral, merger, and ringdown is affected by how fast the larger black hole spins. In particular, I will present results from simulations of merging black holes, completed using the Spectral Einstein Code (black-holes.org/SpEC.html), including some new, long simulations designed to mimic black hole-neutron star mergers. I will present comparisons of the numerical waveforms with analytic <span class="hlt">approximations</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OptFT..30..163M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OptFT..30..163M"><span>Full-duplex radio over fiber link with colorless source-free base station based on single sideband optical mm-<span class="hlt">wave</span> signal with polarization <span class="hlt">rotated</span> optical carrier</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Jianxin</p> <p>2016-07-01</p> <p>A full-duplex radio-over fiber (RoF) link scheme based on single sideband (SSB) optical millimeter (mm)-<span class="hlt">wave</span> signal with polarization-<span class="hlt">rotated</span> optical carrier is proposed to realize the source-free colorless base station (BS), in which a polarization beam splitter (PBS) is used to abstract part of the optical carrier for conveying the uplink data. Since the optical carrier for the uplink does not bear the downlink signal, no cross-talk from the downlink contaminates the uplink signal. The simulation results demonstrate that both down- and up-links maintain good performance. The mm-<span class="hlt">wave</span> signal distribution network based on the proposed full duplex fiber link scheme can use the uniform source-free colorless BSs, which makes the access system very simpler.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ApPhL..98y4103S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ApPhL..98y4103S"><span><span class="hlt">Rotational</span> microfluidic motor for on-chip microcentrifugation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shilton, Richie J.; Glass, Nick R.; Chan, Peggy; Yeo, Leslie Y.; Friend, James R.</p> <p>2011-06-01</p> <p>We report on the design of a surface acoustic <span class="hlt">wave</span> (SAW) driven fluid-coupled micromotor which runs at high <span class="hlt">rotational</span> velocities. A pair of opposing SAWs generated on a lithium niobate substrate are each obliquely passed into either side of a fluid drop to drive <span class="hlt">rotation</span> of the fluid, and the thin circular disk set on the drop. Using water for the drop, a 5 mm diameter disk was driven with <span class="hlt">rotation</span> speeds and start-up torques up to 2250 rpm and 60 nN m, respectively. Most importantly for lab-on-a-chip applications, radial accelerations of 172 m/s2 was obtained, presenting possibilities for microcentrifugation, flow sequencing, assays, and cell culturing in truly microscale lab-on-a-chip devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25404349','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25404349"><span>Transition from geostrophic turbulence to inertia-gravity <span class="hlt">waves</span> in the atmospheric energy spectrum.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Callies, Jörn; Ferrari, Raffaele; Bühler, Oliver</p> <p>2014-12-02</p> <p>Midlatitude fluctuations of the atmospheric winds on scales of thousands of kilometers, the most energetic of such fluctuations, are strongly constrained by the Earth's <span class="hlt">rotation</span> and the atmosphere's stratification. As a result of these constraints, the flow is quasi-2D and energy is trapped at large scales—nonlinear turbulent interactions transfer energy to larger scales, but not to smaller scales. Aircraft observations of wind and temperature near the tropopause indicate that fluctuations at horizontal scales smaller than about 500 km are more energetic than expected from these quasi-2D dynamics. We present an analysis of the observations that indicates that these smaller-scale motions are due to <span class="hlt">approximately</span> linear inertia-gravity <span class="hlt">waves</span>, contrary to recent claims that these scales are strongly turbulent. Specifically, the aircraft velocity and temperature measurements are separated into two components: one due to the quasi-2D dynamics and one due to linear inertia-gravity <span class="hlt">waves</span>. Quasi-2D dynamics dominate at scales larger than 500 km; inertia-gravity <span class="hlt">waves</span> dominate at scales smaller than 500 km.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4260586','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4260586"><span>Transition from geostrophic turbulence to inertia–gravity <span class="hlt">waves</span> in the atmospheric energy spectrum</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Callies, Jörn; Ferrari, Raffaele; Bühler, Oliver</p> <p>2014-01-01</p> <p>Midlatitude fluctuations of the atmospheric winds on scales of thousands of kilometers, the most energetic of such fluctuations, are strongly constrained by the Earth’s <span class="hlt">rotation</span> and the atmosphere’s stratification. As a result of these constraints, the flow is quasi-2D and energy is trapped at large scales—nonlinear turbulent interactions transfer energy to larger scales, but not to smaller scales. Aircraft observations of wind and temperature near the tropopause indicate that fluctuations at horizontal scales smaller than about 500 km are more energetic than expected from these quasi-2D dynamics. We present an analysis of the observations that indicates that these smaller-scale motions are due to <span class="hlt">approximately</span> linear inertia–gravity <span class="hlt">waves</span>, contrary to recent claims that these scales are strongly turbulent. Specifically, the aircraft velocity and temperature measurements are separated into two components: one due to the quasi-2D dynamics and one due to linear inertia–gravity <span class="hlt">waves</span>. Quasi-2D dynamics dominate at scales larger than 500 km; inertia–gravity <span class="hlt">waves</span> dominate at scales smaller than 500 km. PMID:25404349</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950014640','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950014640"><span>On the transition towards slow manifold in shallow-water and 3D Euler equations in a <span class="hlt">rotating</span> frame</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mahalov, A.</p> <p>1994-01-01</p> <p>The long-time, asymptotic state of <span class="hlt">rotating</span> homogeneous shallow-water equations is investigated. Our analysis is based on long-time averaged <span class="hlt">rotating</span> shallow-water equations describing interactions of large-scale, horizontal, two-dimensional motions with surface inertial-gravity <span class="hlt">waves</span> field for a shallow, uniformly <span class="hlt">rotating</span> fluid layer. These equations are obtained in two steps: first by introducing a Poincare/Kelvin linear propagator directly into classical shallow-water equations, then by averaging. The averaged equations describe interaction of <span class="hlt">wave</span> fields with large-scale motions on time scales long compared to the time scale 1/f(sub o) introduced by <span class="hlt">rotation</span> (f(sub o)/2-angular velocity of background <span class="hlt">rotation</span>). The present analysis is similar to the one presented by Waleffe (1991) for 3D Euler equations in a <span class="hlt">rotating</span> frame. However, since three-<span class="hlt">wave</span> interactions in <span class="hlt">rotating</span> shallow-water equations are forbidden, the final equations describing the asymptotic state are simplified considerably. Special emphasis is given to a new conservation law found in the asymptotic state and decoupling of the dynamics of the divergence free part of the velocity field. The possible rising of a decoupled dynamics in the asymptotic state is also investigated for homogeneous turbulence subjected to a background <span class="hlt">rotation</span>. In our analysis we use long-time expansion, where the velocity field is decomposed into the 'slow manifold' part (the manifold which is unaffected by the linear 'rapid' effects of <span class="hlt">rotation</span> or the inertial <span class="hlt">waves</span>) and a formal 3D disturbance. We derive the physical space version of the long-time averaged equations and consider an invariant, basis-free derivation. This formulation can be used to generalize Waleffe's (1991) helical decomposition to viscous inhomogeneous flows (e.g. problems in cylindrical geometry with no-slip boundary conditions on the cylinder surface and homogeneous in the vertical direction).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24817308','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24817308"><span>Electrical <span class="hlt">wave</span> propagation in an anisotropic model of the left ventricle based on analytical description of cardiac architecture.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pravdin, Sergey F; Dierckx, Hans; Katsnelson, Leonid B; Solovyova, Olga; Markhasin, Vladimir S; Panfilov, Alexander V</p> <p>2014-01-01</p> <p>We develop a numerical approach based on our recent analytical model of fiber structure in the left ventricle of the human heart. A special curvilinear coordinate system is proposed to analytically include realistic ventricular shape and myofiber directions. With this anatomical model, electrophysiological simulations can be performed on a rectangular coordinate grid. We apply our method to study the effect of fiber <span class="hlt">rotation</span> and electrical anisotropy of cardiac tissue (i.e., the ratio of the conductivity coefficients along and across the myocardial fibers) on <span class="hlt">wave</span> propagation using the ten Tusscher-Panfilov (2006) ionic model for human ventricular cells. We show that fiber <span class="hlt">rotation</span> increases the speed of cardiac activation and attenuates the effects of anisotropy. Our results show that the fiber <span class="hlt">rotation</span> in the heart is an important factor underlying cardiac excitation. We also study scroll <span class="hlt">wave</span> dynamics in our model and show the drift of a scroll <span class="hlt">wave</span> filament whose velocity depends non-monotonically on the fiber <span class="hlt">rotation</span> angle; the period of scroll <span class="hlt">wave</span> <span class="hlt">rotation</span> decreases with an increase of the fiber <span class="hlt">rotation</span> angle; an increase in anisotropy may cause the breakup of a scroll <span class="hlt">wave</span>, similar to the mother rotor mechanism of ventricular fibrillation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4015904','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4015904"><span>Electrical <span class="hlt">Wave</span> Propagation in an Anisotropic Model of the Left Ventricle Based on Analytical Description of Cardiac Architecture</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pravdin, Sergey F.; Dierckx, Hans; Katsnelson, Leonid B.; Solovyova, Olga; Markhasin, Vladimir S.; Panfilov, Alexander V.</p> <p>2014-01-01</p> <p>We develop a numerical approach based on our recent analytical model of fiber structure in the left ventricle of the human heart. A special curvilinear coordinate system is proposed to analytically include realistic ventricular shape and myofiber directions. With this anatomical model, electrophysiological simulations can be performed on a rectangular coordinate grid. We apply our method to study the effect of fiber <span class="hlt">rotation</span> and electrical anisotropy of cardiac tissue (i.e., the ratio of the conductivity coefficients along and across the myocardial fibers) on <span class="hlt">wave</span> propagation using the ten Tusscher–Panfilov (2006) ionic model for human ventricular cells. We show that fiber <span class="hlt">rotation</span> increases the speed of cardiac activation and attenuates the effects of anisotropy. Our results show that the fiber <span class="hlt">rotation</span> in the heart is an important factor underlying cardiac excitation. We also study scroll <span class="hlt">wave</span> dynamics in our model and show the drift of a scroll <span class="hlt">wave</span> filament whose velocity depends non-monotonically on the fiber <span class="hlt">rotation</span> angle; the period of scroll <span class="hlt">wave</span> <span class="hlt">rotation</span> decreases with an increase of the fiber <span class="hlt">rotation</span> angle; an increase in anisotropy may cause the breakup of a scroll <span class="hlt">wave</span>, similar to the mother rotor mechanism of ventricular fibrillation. PMID:24817308</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017isms.confETF05A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017isms.confETF05A"><span>The Astrophysical Weeds: <span class="hlt">Rotational</span> Transitions in Excited Vibrational States</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alonso, José L.; Kolesniková, Lucie; Alonso, Elena R.; Mata, Santiago</p> <p>2017-06-01</p> <p>The number of unidentified lines in the millimeter and submillimeter <span class="hlt">wave</span> surveys of the interstellar medium has grown rapidly. The major contributions are due to <span class="hlt">rotational</span> transitions in excited vibrational states of a relatively few molecules that are called the astrophysical weeds. necessary data to deal with spectral lines from astrophysical weeds species can be obtained from detailed laboratory <span class="hlt">rotational</span> measurements in the microwave and millimeter <span class="hlt">wave</span> region. A general procedure is being used at Valladolid combining different time and/or frequency domain spectroscopic tools of varying importance for providing the precise set of spectroscopic constants that could be used to search for this species in the ISM. This is illustrated in the present contribution through its application to several significant examples. Fortman, S. M., Medvedev, I. R., Neese, C.F., & De Lucia, F.C. 2010, ApJ,725, 1682 <span class="hlt">Rotational</span> Spectra in 29 Vibrationally Excited States of Interstellar Aminoacetonitrile, L. Kolesniková, E. R. Alonso, S. Mata, and J. L. Alonso, The Astrophysical Journal Supplement Series 2017, (in press).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19123135','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19123135"><span><span class="hlt">Rotation</span> in Xenopus laevis embryos during the second cell cycle.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Starodubov, Sergey M; Golychenkov, Vladimir A</p> <p>2009-01-01</p> <p>Using time-lapse video recording and comparing successive digital images, we found that 38% of Xenopus laevis embryos (n=118) exhibited <span class="hlt">rotation</span> during the second cell cycle. This <span class="hlt">rotation</span>, which we term the second <span class="hlt">rotation</span>, started <span class="hlt">approximately</span> during the appearance of the first cleavage furrow and proceeded clockwise or counterclockwise around the vertical axis. <span class="hlt">Rotations</span> lasted for 5-30 minutes, i.e. up to the beginning of the third cell cycle. The mean <span class="hlt">rotation</span> angle was 36.4 degrees, with a maximum <span class="hlt">rotation</span> of 77 degrees. No mortality was observed among the embryos exhibiting <span class="hlt">rotation</span>. The second <span class="hlt">rotation</span> was observed to be similar to the well-known fertilization <span class="hlt">rotation</span> which takes place during the first cell cycle. The possible nature and significance of the second <span class="hlt">rotation</span> are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26900841','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26900841"><span>The Fundamental Structure and the Reproduction of Spiral <span class="hlt">Wave</span> in a Two-Dimensional Excitable Lattice.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Qian, Yu; Zhang, Zhaoyang</p> <p>2016-01-01</p> <p>In this paper we have systematically investigated the fundamental structure and the reproduction of spiral <span class="hlt">wave</span> in a two-dimensional excitable lattice. A periodically <span class="hlt">rotating</span> spiral <span class="hlt">wave</span> is introduced as the model to reproduce spiral <span class="hlt">wave</span> artificially. Interestingly, by using the dominant phase-advanced driving analysis method, the fundamental structure containing the loop structure and the <span class="hlt">wave</span> propagation paths has been revealed, which can expose the periodically <span class="hlt">rotating</span> orbit of spiral tip and the charity of spiral <span class="hlt">wave</span> clearly. Furthermore, the fundamental structure is utilized as the core for artificial spiral <span class="hlt">wave</span>. Additionally, the appropriate parameter region, in which the artificial spiral <span class="hlt">wave</span> can be reproduced, is studied. Finally, we discuss the robustness of artificial spiral <span class="hlt">wave</span> to defects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910006108','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910006108"><span><span class="hlt">Rotating</span> reactor studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roberts, Glyn O.</p> <p>1991-01-01</p> <p>Undesired gravitational effects such as convection or sedimentation in a fluid can sometimes be avoided or decreased by the use of a closed chamber uniformly <span class="hlt">rotated</span> about a horizontal axis. In a previous study, the spiral orbits of a heavy or buoyant particle in a uniformly <span class="hlt">rotating</span> fluid were determined. The particles move in circles, and spiral in or out under the combined effects of the centrifugal force and centrifugal buoyancy. A optimization problem for the <span class="hlt">rotation</span> rate of a cylindrical reactor <span class="hlt">rotated</span> about its axis and containing distributed particles was formulated and solved. Related studies in several areas are addressed. A computer program based on the analysis was upgraded by correcting some minor errors, adding a sophisticated screen-and-printer graphics capability and other output options, and by improving the automation. The design, performance, and analysis of a series of experiments with monodisperse polystyrene latex microspheres in water were supported to test the theory and its limitations. The theory was amply confirmed at high <span class="hlt">rotation</span> rates. However, at low <span class="hlt">rotation</span> rates (1 rpm or less) the assumption of uniform solid-body <span class="hlt">rotation</span> of the fluid became invalid, and there were increasingly strong secondary motions driven by variations in the mean fluid density due to variations in the particle concentration. In these tests the increase in the mean fluid density due to the particles was of order 0.015 percent. To a first <span class="hlt">approximation</span>, these flows are driven by the buoyancy in a thin crescent-shaped depleted layer on the descending side of the <span class="hlt">rotating</span> reactor. This buoyancy distribution is balanced by viscosity near the walls, and by the Coriolis force in the interior. A full analysis is beyond the scope of this study. Secondary flows are likely to be stronger for buoyant particles, which spiral in towards the neutral point near the <span class="hlt">rotation</span> axis under the influence of their centrifugal buoyancy. This is because the depleted layer is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19581959','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19581959"><span>Polarization splitter and polarization <span class="hlt">rotator</span> designs based on transformation optics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kwon, Do-Hoon; Werner, Douglas H</p> <p>2008-11-10</p> <p>The transformation optics technique is employed in this paper to design two optical devices - a two-dimensional polarization splitter and a three-dimensional polarization <span class="hlt">rotator</span> for propagating beams. The polarization splitter translates the TM- and the TE-polarized components of an incident beam in opposite directions (i.e., shifted up or shifted down). The polarization <span class="hlt">rotator</span> <span class="hlt">rotates</span> the polarization state of an incoming beam by an arbitrary angle. Both optical devices are reflectionless at the entry and exit interfaces. Design details and full-<span class="hlt">wave</span> simulation results are provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EP%26S...69..124S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EP%26S...69..124S"><span>Analysis of <span class="hlt">rotation</span> sensor data from the SINAPS@ Kefalonia (Greece) post-seismic experiment—link to surface geology and wavefield characteristics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sbaa, Sarah; Hollender, Fabrice; Perron, Vincent; Imtiaz, Afifa; Bard, Pierre-Yves; Mariscal, Armand; Cochard, Alain; Dujardin, Alain</p> <p>2017-09-01</p> <p>Although <span class="hlt">rotational</span> seismology has progressed in recent decades, the links between <span class="hlt">rotational</span> ground motion and site soil conditions are poorly documented. New experiments were performed on Kefalonia Island (Greece) following two large earthquakes ( M W = 6.0, M W = 5.9) in early 2014 on two well-characterized sites (soft soil, V S30 250 m/s; rock, V S30 830 m/s, V S30 being harmonic average shear-<span class="hlt">wave</span> velocity between 0 and 30 m depth). These earthquakes led to large six-component (three translations and three <span class="hlt">rotations</span>) datasets of hundreds of well-recorded events. The relationship between peak translational acceleration versus peak <span class="hlt">rotational</span> velocity is found sensitive to the site conditions mainly for the <span class="hlt">rotation</span> around the vertical axis (torsion; dominated by Love <span class="hlt">waves</span>): the stiffer the soil, the lower the torsion, for a given level of translational acceleration. For <span class="hlt">rotation</span> around the horizontal axes (rocking; dominated by Rayleigh <span class="hlt">waves</span>), this acceleration/<span class="hlt">rotation</span> relationship exhibits much weaker differences between soft and rock sites. Using only the <span class="hlt">rotation</span> sensor, an estimate of the Love-to-Rayleigh energy ratios could be carried out and provided the same results as previous studies that have analyzed the Love- and Rayleigh-<span class="hlt">wave</span> energy proportions using data from translational arrays deployed at the same two sites. The coupling of translational and <span class="hlt">rotational</span> measurements appears to be useful, not only for direct applications of engineering seismology, but also to investigate the composition of the wavefield, while avoiding deployment of dense arrays. The availability of new, low-noise <span class="hlt">rotation</span> sensors that are easy to deploy in the field is of great interest and should extend the use of <span class="hlt">rotation</span> sensors and expand their possible applications.[Figure not available: see fulltext.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730017140','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730017140"><span>Alfven <span class="hlt">wave</span> refraction by interplanetary inhomogeneities</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Daily, W. D.</p> <p>1973-01-01</p> <p>Pioneer 6 magnetic data reveals that the propagation direction of Alfven <span class="hlt">waves</span> in the interplanetary medium is strongly oriented along the ambient field. Magnetic fluctuations of frequencies up to 1/30 sec in the spacecraft frame are shown to satisfy a necessary condition for Alfven <span class="hlt">wave</span> normal. It appears from this analysis that geometrical hydromagnetics may satisfactorily describe deviation of the <span class="hlt">wave</span> normal from the background field. The <span class="hlt">rotational</span> discontinuity is likely also to propagate along the field lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22679424-gravitational-wave-production-hawking-radiation-from-rotating-primordial-black-holes','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22679424-gravitational-wave-production-hawking-radiation-from-rotating-primordial-black-holes"><span>Gravitational <span class="hlt">wave</span> production by Hawking radiation from <span class="hlt">rotating</span> primordial black holes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Dong, Ruifeng; Kinney, William H.; Stojkovic, Dejan, E-mail: ruifengd@buffalo.edu, E-mail: whkinney@buffalo.edu, E-mail: ds77@buffalo.edu</p> <p></p> <p>In this paper we analyze in detail a rarely discussed question of gravity <span class="hlt">wave</span> production from evaporating primordial black holes. These black holes emit gravitons which are, at classical level, registered as gravity <span class="hlt">waves</span>. We use the latest constraints on their abundance, and calculate the power emitted in gravitons at the time of their evaporation. We then solve the coupled system of equations that gives us the evolution of the frequency and amplitude of gravity <span class="hlt">waves</span> during the expansion of the universe. The spectrum of gravitational <span class="hlt">waves</span> that can be detected today depends on multiple factors: fraction of the totalmore » energy density which was occupied by primordial black holes, the epoch in which they were formed, and quantities like their mass and angular momentum. We conclude that very small primordial black holes which evaporate before the big-bang nucleosynthesis emit gravitons whose spectral energy fraction today can be as large as 10{sup −7.5}. On the other hand, those which are massive enough so that they still exist now can yield a signal as high as 10{sup −6.5}. However, typical frequencies of the gravity <span class="hlt">waves</span> from primordial black holes are still too high to be observed with the current and near future gravity <span class="hlt">wave</span> observations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930038594&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcentrifugal%2Bcompressor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930038594&hterms=centrifugal+compressor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dcentrifugal%2Bcompressor"><span>Prediction of active control of subsonic centrifugal compressor <span class="hlt">rotating</span> stall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lawless, Patrick B.; Fleeter, Sanford</p> <p>1993-01-01</p> <p>A mathematical model is developed to predict the suppression of <span class="hlt">rotating</span> stall in a centrifugal compressor with a vaned diffuser. This model is based on the employment of a control vortical waveform generated upstream of the impeller inlet to damp weak potential disturbances that are the early stages of <span class="hlt">rotating</span> stall. The control system is analyzed by matching the perturbation pressure in the compressor inlet and exit flow fields with a model for the unsteady behavior of the compressor. The model was effective at predicting the stalling behavior of the Purdue Low Speed Centrifugal Compressor for two distinctly different stall patterns. Predictions made for the effect of a controlled inlet vorticity <span class="hlt">wave</span> on the stability of the compressor show that for minimum control <span class="hlt">wave</span> magnitudes, on the order of the total inlet disturbance magnitude, significant damping of the instability can be achieved. For control <span class="hlt">waves</span> of sufficient amplitude, the control phase angle appears to be the most important factor in maintaining a stable condition in the compressor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860048947&hterms=Gravitational+motion+system&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DGravitational%2Bmotion%2Bsystem','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860048947&hterms=Gravitational+motion+system&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DGravitational%2Bmotion%2Bsystem"><span><span class="hlt">Approximation</span> methods in gravitational-radiation theory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Will, C. M.</p> <p>1986-01-01</p> <p>The observation of gravitational-radiation damping in the binary pulsar PSR 1913 + 16 and the ongoing experimental search for gravitational <span class="hlt">waves</span> of extraterrestrial origin have made the theory of gravitational radiation an active branch of classical general relativity. In calculations of gravitational radiation, <span class="hlt">approximation</span> methods play a crucial role. Recent developments are summarized in two areas in which <span class="hlt">approximations</span> are important: (a) the quadrupole approxiamtion, which determines the energy flux and the radiation reaction forces in weak-field, slow-motion, source-within-the-near-zone systems such as the binary pulsar; and (b) the normal modes of oscillation of black holes, where the Wentzel-Kramers-Brillouin <span class="hlt">approximation</span> gives accurate estimates of the complex frequencies of the modes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770052661&hterms=fair+value&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfair%2Bvalue','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770052661&hterms=fair+value&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfair%2Bvalue"><span>An analytical theory of planetary <span class="hlt">rotation</span> rates</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Harris, A. W.</p> <p>1977-01-01</p> <p>An <span class="hlt">approximate</span> analytical theory is derived for the rate of <span class="hlt">rotation</span> acquired by a planet as it grows from the solar nebula. This theory was motivated by a numerical study by Giuli, and yields fair agreement with his results. The periods of planetary <span class="hlt">rotation</span> obtained are proportional to planetesimal encounter velocity, and appear to suggest lower values of this velocity than are commonly assumed to have existed during planetary formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030022712','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030022712"><span>Rayleigh-Taylor Gravity <span class="hlt">Waves</span> and Quasiperiodic Oscillation Phenomenon in X-ray Binaries</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Titarchuk, Lev</p> <p>2002-01-01</p> <p>Accretion onto compact objects in X-ray binaries (black hole, neutron star (NS), white dwarf) is characterized by non-uniform flow density profiles. Such an effect of heterogeneity in presence of gravitational forces and pressure gradients exhibits Rayleigh-Taylor gravity <span class="hlt">waves</span> (RTGW). They should be seen as quasiperiodic <span class="hlt">wave</span> oscillations (QPO) of the accretion flow in the transition (boundary) layer between the Keplerian disk and the central object. In this paper the author shows that the main QPO frequency, which is very close to the Keplerian frequency, is split into separate frequencies (hybrid and low branch) under the influence of the gravitational forces in the <span class="hlt">rotational</span> frame of reference. The RTGWs must be present and the related QPOs should be detected in any system where the gravity, buoyancy and Coriolis force effects cannot be excluded (even in the Earth and solar environments). The observed low and high QPO frequencies are an intrinsic signature of the RTGW. The author elaborates the conditions for the density profile when the RTGW oscillations are stable. A comparison of the inferred QPO frequencies with QPO observations is presented. The author finds that hectohertz frequencies detected from NS binaries can be identified as the RTGW low branch frequencies. The author also predicts that an observer can see the double NS spin frequency during the NS long (super) burst events when the pressure gradients and buoyant forces are suppressed. The Coriolis force is the only force which acts in the <span class="hlt">rotational</span> frame of reference and its presence causes perfect coherent pulsations with a frequency twice of the NS spin. The QPO observations of neutron binaries have established that the high QPO frequencies do not go beyond of the certain upper limit. The author explains this observational effect as a result of the density profile inversions. Also the author demonstrates that a particular problem of the gravity <span class="hlt">waves</span> in the <span class="hlt">rotational</span> frame of reference in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ARep...62..299M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ARep...62..299M"><span>A Numerical-Analytical Approach to Modeling the Axial <span class="hlt">Rotation</span> of the Earth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Markov, Yu. G.; Perepelkin, V. V.; Rykhlova, L. V.; Filippova, A. S.</p> <p>2018-04-01</p> <p>A model for the non-uniform axial <span class="hlt">rotation</span> of the Earth is studied using a celestial-mechanical approach and numerical simulations. The application of an <span class="hlt">approximate</span> model containing a small number of parameters to predict variations of the axial <span class="hlt">rotation</span> velocity of the Earth over short time intervals is justified. This <span class="hlt">approximate</span> model is obtained by averaging variable parameters that are subject to small variations due to non-stationarity of the perturbing factors. The model is verified and compared with predictions over a long time interval published by the International Earth <span class="hlt">Rotation</span> and Reference Systems Service (IERS).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006APS..MARY26001S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006APS..MARY26001S"><span>Electrical <span class="hlt">Wave</span> Propagation in a Minimally Realistic Fiber Architecture Model of the Left Ventricle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Xianfeng; Setayeshgar, Sima</p> <p>2006-03-01</p> <p>Experimental results indicate a nested, layered geometry for the fiber surfaces of the left ventricle, where fiber directions are <span class="hlt">approximately</span> aligned in each surface and gradually <span class="hlt">rotate</span> through the thickness of the ventricle. Numerical and analytical results have highlighted the importance of this <span class="hlt">rotating</span> anisotropy and its possible destabilizing role on the dynamics of scroll <span class="hlt">waves</span> in excitable media with application to the heart. Based on the work of Peskin[1] and Peskin and McQueen[2], we present a minimally realistic model of the left ventricle that adequately captures the geometry and anisotropic properties of the heart as a conducting medium while being easily parallelizable, and computationally more tractable than fully realistic anatomical models. Complementary to fully realistic and anatomically-based computational approaches, studies using such a minimal model with the addition of successively realistic features, such as excitation-contraction coupling, should provide unique insight into the basic mechanisms of formation and obliteration of electrical <span class="hlt">wave</span> instabilities. We describe our construction, implementation and validation of this model. [1] C. S. Peskin, Communications on Pure and Applied Mathematics 42, 79 (1989). [2] C. S. Peskin and D. M. McQueen, in Case Studies in Mathematical Modeling: Ecology, Physiology, and Cell Biology, 309(1996)</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21502460-analytic-derivation-approximate-su-symmetry-inside-symmetry-triangle-interacting-boson-approximation-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21502460-analytic-derivation-approximate-su-symmetry-inside-symmetry-triangle-interacting-boson-approximation-model"><span>Analytic derivation of an <span class="hlt">approximate</span> SU(3) symmetry inside the symmetry triangle of the interacting boson <span class="hlt">approximation</span> model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Bonatsos, Dennis; Karampagia, S.; Casten, R. F.</p> <p>2011-05-15</p> <p>Using a contraction of the SU(3) algebra to the algebra of the rigid <span class="hlt">rotator</span> in the large-boson-number limit of the interacting boson <span class="hlt">approximation</span> (IBA) model, a line is found inside the symmetry triangle of the IBA, along which the SU(3) symmetry is preserved. The line extends from the SU(3) vertex to near the critical line of the first-order shape/phase transition separating the spherical and prolate deformed phases, and it lies within the Alhassid-Whelan arc of regularity, the unique valley of regularity connecting the SU(3) and U(5) vertices in the midst of chaotic regions. In addition to providing an explanation formore » the existence of the arc of regularity, the present line represents an example of an analytically determined <span class="hlt">approximate</span> symmetry in the interior of the symmetry triangle of the IBA. The method is applicable to algebraic models possessing subalgebras amenable to contraction. This condition is equivalent to algebras in which the equilibrium ground state and its <span class="hlt">rotational</span> band become energetically isolated from intrinsic excitations, as typified by deformed solutions to the IBA for large numbers of valence nucleons.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22617178-nonlinear-theory-magnetohydrodynamic-flows-compressible-fluid-shallow-water-approximation','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22617178-nonlinear-theory-magnetohydrodynamic-flows-compressible-fluid-shallow-water-approximation"><span>Nonlinear theory of magnetohydrodynamic flows of a compressible fluid in the shallow water <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Klimachkov, D. A., E-mail: klimchakovdmitry@gmail.com; Petrosyan, A. S., E-mail: apetrosy@iki.rssi.ru</p> <p>2016-09-15</p> <p>Shallow water magnetohydrodynamic (MHD) theory describing incompressible flows of plasma is generalized to the case of compressible flows. A system of MHD equations is obtained that describes the flow of a thin layer of compressible <span class="hlt">rotating</span> plasma in a gravitational field in the shallow water <span class="hlt">approximation</span>. The system of quasilinear hyperbolic equations obtained admits a complete simple <span class="hlt">wave</span> analysis and a solution to the initial discontinuity decay problem in the simplest version of nonrotating flows. In the new equations, sound <span class="hlt">waves</span> are filtered out, and the dependence of density on pressure on large scales is taken into account that describesmore » static compressibility phenomena. In the equations obtained, the mass conservation law is formulated for a variable that nontrivially depends on the shape of the lower boundary, the characteristic vertical scale of the flow, and the scale of heights at which the variation of density becomes significant. A simple <span class="hlt">wave</span> theory is developed for the system of equations obtained. All self-similar discontinuous solutions and all continuous centered self-similar solutions of the system are obtained. The initial discontinuity decay problem is solved explicitly for compressible MHD equations in the shallow water <span class="hlt">approximation</span>. It is shown that there exist five different configurations that provide a solution to the initial discontinuity decay problem. For each configuration, conditions are found that are necessary and sufficient for its implementation. Differences between incompressible and compressible cases are analyzed. In spite of the formal similarity between the solutions in the classical case of MHD flows of an incompressible and compressible fluids, the nonlinear dynamics described by the solutions are essentially different due to the difference in the expressions for the squared propagation velocity of weak perturbations. In addition, the solutions obtained describe new physical phenomena related to the dependence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.476.1234A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.476.1234A"><span>K2 photometry and HERMES spectroscopy of the blue supergiant ρ Leo: <span class="hlt">rotational</span> wind modulation and low-frequency <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aerts, C.; Bowman, D. M.; Símon-Díaz, S.; Buysschaert, B.; Johnston, C.; Moravveji, E.; Beck, P. G.; De Cat, P.; Triana, S.; Aigrain, S.; Castro, N.; Huber, D.; White, T.</p> <p>2018-05-01</p> <p>We present an 80-d long uninterrupted high-cadence K2 light curve of the B1Iab supergiant ρ Leo (HD 91316), deduced with the method of halo photometry. This light curve reveals a dominant frequency of frot = 0.0373 d-1 and its harmonics. This dominant frequency corresponds with a <span class="hlt">rotation</span> period of 26.8 d and is subject to amplitude and phase modulation. The K2 photometry additionally reveals multiperiodic low-frequency variability (<1.5 d-1) and is in full agreement with low-cadence high-resolution spectroscopy assembled during 1800 d. The spectroscopy reveals <span class="hlt">rotational</span> modulation by a dynamic aspherical wind with an amplitude of about 20 km s-1 in the H α line, as well as photospheric velocity variations of a few km s-1 at frequencies in the range 0.2-0.6 d-1 in the Si III 4567 Å line. Given the large macroturbulence needed to explain the spectral line broadening of the star, we interpret the detected photospheric velocity as due to travelling superinertial low-degree large-scale gravity <span class="hlt">waves</span> with dominant tangential amplitudes and discuss why ρ Leo is an excellent target to study how the observed photospheric variability propagates into the wind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhDT........66K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT........66K"><span><span class="hlt">Rotating</span> Space Elevators: Classical and Statistical Mechanics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knudsen, Steven</p> <p></p> <p>We investigate a novel and unique dynamical system, the <span class="hlt">Rotating</span> Space Elevator (RSE). The RSE is a multiply <span class="hlt">rotating</span> system of strings reaching beyond the Earth geo-synchronous satellite orbit. Objects sliding along the RSE string ("climbers") do not require internal engines or propulsion to be transported far away from the Earth's surface. The RSE thus solves a major problem in the space elevator technology which is how to supply the energy to the climbers moving along the string. The RSE is a double <span class="hlt">rotating</span> floppy string. The RSE can be made in various shapes that are stabilized by an <span class="hlt">approximate</span> equilibrium between the gravitational and inertial forces acting in the double <span class="hlt">rotating</span> frame. The RSE exhibits a variety of interesting dynamical phenomena studied in this thesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21408437-quantum-mechanics-rotating-radio-frequency-traps-penning-traps-quadrupole-rotating-field','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21408437-quantum-mechanics-rotating-radio-frequency-traps-penning-traps-quadrupole-rotating-field"><span>Quantum mechanics in <span class="hlt">rotating</span>-radio-frequency traps and Penning traps with a quadrupole <span class="hlt">rotating</span> field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Abe, K.; Hasegawa, T.</p> <p>2010-03-15</p> <p>Quantum-mechanical analysis of ion motion in a <span class="hlt">rotating</span>-radio-frequency (rrf) trap or in a Penning trap with a quadrupole <span class="hlt">rotating</span> field is carried out. Rrf traps were introduced by Hasegawa and Bollinger [Phys. Rev. A 72, 043404 (2005)]. The classical motion of a single ion in this trap is described by only trigonometric functions, whereas in the conventional linear radio-frequency (rf) traps it is by the Mathieu functions. Because of the simple classical motion in the rrf trap, it is expected that the quantum-mechanical analysis of the rrf traps is also simple compared to that of the linear rf traps. Themore » analysis of Penning traps with a quadrupole <span class="hlt">rotating</span> field is also possible in a way similar to the rrf traps. As a result, the Hamiltonian in these traps is the same as the two-dimensional harmonic oscillator, and energy levels and <span class="hlt">wave</span> functions are derived as exact results. In these traps, it is found that one of the vibrational modes in the <span class="hlt">rotating</span> frame can have negative energy levels, which means that the zero-quantum-number state (''ground'' state) is the highest energy state.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19740047178&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfaraday','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19740047178&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfaraday"><span>Effect of Faraday <span class="hlt">rotation</span> on the circular polarization of the Crab Nebula</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gerver, M. J.</p> <p>1974-01-01</p> <p>The effect of Faraday <span class="hlt">rotation</span> on the circular polarization of an electromagnetic <span class="hlt">wave</span> propagating through a magnetized plasma is calculated for various limits of the plasma and <span class="hlt">wave</span> parameters appropriate to a 30-Hz <span class="hlt">wave</span> in the Crab Nebula. It is shown that a static magnetic field of the proper geometry and only a few times stronger than the <span class="hlt">wave</span> field can reduce the circular polarization of the nonlinear inverse Compton radiation to a value below the observed upper limit.-</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998P%26SS...47..273S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998P%26SS...47..273S"><span>Low frequency <span class="hlt">wave</span> propagation in a cold magnetized dusty plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sarkar, S.; Ghosh, S.; Khan, M.</p> <p>1998-12-01</p> <p>In this paper several characteristics of low frequency <span class="hlt">waves</span> in a cold magnetized dusty plasma propagating parallel and perpendicular to the static background magnetic field have been investigated. In the case of parallel propagation the negatively charged dust particles resonate with the right circularly polarized (RCP) component of em <span class="hlt">waves</span> when the <span class="hlt">wave</span> frequency equals the dust cyclotron frequency. It has been shown that an RCP <span class="hlt">wave</span> in dusty plasma consists of two branches and there exists a region where an RCP <span class="hlt">wave</span> propagation is not possible. Dispersion relation, phase velocity and group velocity of RCP <span class="hlt">waves</span> have been obtained and propagation characteristics have been shown graphically. Poynting flux and Faraday <span class="hlt">rotation</span> angles have been calculated for both lower and upper branches of the RCP <span class="hlt">wave</span>. It has been observed that sense of <span class="hlt">rotation</span> of the plane of polarization of the RCP <span class="hlt">wave</span> corresponding to two distinct branches are opposite. Finally, the effect of dust particles on the induced magnetization from the inverse Faraday effect (IFE) due to the interaction of low frequency propagating and standing em <span class="hlt">waves</span> with dusty plasmas has been evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890043129&hterms=theoretical+framework&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dtheoretical%2Bframework','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890043129&hterms=theoretical+framework&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dtheoretical%2Bframework"><span>A theoretical formulation of <span class="hlt">wave</span>-vortex interactions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, J. Z.; Wu, J. M.</p> <p>1989-01-01</p> <p>A unified theoretical formulation for <span class="hlt">wave</span>-vortex interaction, designated the '(omega, Pi) framework,' is presented. Based on the orthogonal decomposition of fluid dynamic interactions, the formulation can be used to study a variety of problems, including the interaction of a longitudinal (acoustic) <span class="hlt">wave</span> and/or transverse (vortical) <span class="hlt">wave</span> with a main vortex flow. Moreover, the formulation permits a unified treatment of <span class="hlt">wave</span>-vortex interaction at various <span class="hlt">approximate</span> levels, where the normal 'piston' process and tangential 'rubbing' process can be <span class="hlt">approximated</span> dfferently.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.4799S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.4799S"><span><span class="hlt">Rotational</span> motions from the 2016, Central Italy seismic sequence, as observed by an underground ring laser gyroscope</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simonelli, Andreino; Belfi, Jacopo; Beverini, Nicolò; Di Virgilio, Angela; Maccioni, Enrico; De Luca, Gaetano; Saccorotti, Gilberto; Wassermann, Joachim; Igel, Heiner</p> <p>2017-04-01</p> <p>We present analyses of <span class="hlt">rotational</span> and translational ground motions from earthquakes recorded during October-November, 2016, in association with the Central Italy seismic-sequence. We use co-located measurements of the vertical ground <span class="hlt">rotation</span> rate from a large ring laser gyroscope (RLG), and the three components of ground velocity from a broadband seismometer. Both instruments are positioned in a deep underground environment, within the Gran Sasso National Laboratories (LNGS) of the Istituto Nazionale di Fisica Nucleare (INFN). We collected dozen of events spanning the 3.5-5.9 Magnitude range, and epicentral distances between 40 km and 80 km. This data set constitutes an unprecedented observation of the vertical <span class="hlt">rotational</span> motions associated with an intense seismic sequence at local distance. In theory - assuming plane <span class="hlt">wave</span> propagation - the ratio between the vertical <span class="hlt">rotation</span> rate and the transverse acceleration permits, in a single station approach, the estimation of apparent phase velocity in the case of SH arrivals or real phase velocity in the case of Love surface <span class="hlt">waves</span>. This is a standard approach for the analysis of earthquakes at teleseismic distances, and the results reported by the literature are compatible with the expected phase velocities from the PREM model. Here we extend the application of the same approach to local events, thus exploring higher frequency ranges and larger <span class="hlt">rotation</span> rate amplitudes. We use a novel approach to joint <span class="hlt">rotation</span>/acceleration analysis based on the continuous wavelet transform (CWT). Wavelet coherence (WTC) is used as a filter for identifying those regions of the time-period plane where the <span class="hlt">rotation</span> rate and transverse acceleration signals exhibit significant coherence. This allows retrieving estimates of phase velocities over the period range spanned by correlated arrivals. Coherency among ground <span class="hlt">rotation</span> and translation is also observed throughout the coda of the P-<span class="hlt">wave</span> arrival, an observation which is interpreted in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4762983','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4762983"><span>The Fundamental Structure and the Reproduction of Spiral <span class="hlt">Wave</span> in a Two-Dimensional Excitable Lattice</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Qian, Yu; Zhang, Zhaoyang</p> <p>2016-01-01</p> <p>In this paper we have systematically investigated the fundamental structure and the reproduction of spiral <span class="hlt">wave</span> in a two-dimensional excitable lattice. A periodically <span class="hlt">rotating</span> spiral <span class="hlt">wave</span> is introduced as the model to reproduce spiral <span class="hlt">wave</span> artificially. Interestingly, by using the dominant phase-advanced driving analysis method, the fundamental structure containing the loop structure and the <span class="hlt">wave</span> propagation paths has been revealed, which can expose the periodically <span class="hlt">rotating</span> orbit of spiral tip and the charity of spiral <span class="hlt">wave</span> clearly. Furthermore, the fundamental structure is utilized as the core for artificial spiral <span class="hlt">wave</span>. Additionally, the appropriate parameter region, in which the artificial spiral <span class="hlt">wave</span> can be reproduced, is studied. Finally, we discuss the robustness of artificial spiral <span class="hlt">wave</span> to defects. PMID:26900841</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.213.1281R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.213.1281R"><span>Internally driven inertial <span class="hlt">waves</span> in geodynamo simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ranjan, A.; Davidson, P. A.; Christensen, U. R.; Wicht, J.</p> <p>2018-05-01</p> <p>Inertial <span class="hlt">waves</span> are oscillations in a <span class="hlt">rotating</span> fluid, such as the Earth's outer core, which result from the restoring action of the Coriolis force. In an earlier work, it was argued by Davidson that inertial <span class="hlt">waves</span> launched near the equatorial regions could be important for the α2 dynamo mechanism, as they can maintain a helicity distribution which is negative (positive) in the north (south). Here, we identify such internally driven inertial <span class="hlt">waves</span>, triggered by buoyant anomalies in the equatorial regions in a strongly forced geodynamo simulation. Using the time derivative of vertical velocity, ∂uz/∂t, as a diagnostic for traveling <span class="hlt">wave</span> fronts, we find that the horizontal movement in the buoyancy field near the equator is well correlated with a corresponding movement of the fluid far from the equator. Moreover, the azimuthally averaged spectrum of ∂uz/∂t lies in the inertial <span class="hlt">wave</span> frequency range. We also test the dispersion properties of the <span class="hlt">waves</span> by computing the spectral energy as a function of frequency, ϖ, and the dispersion angle, θ. Our results suggest that the columnar flow in the <span class="hlt">rotation</span>-dominated core, which is an important ingredient for the maintenance of a dipolar magnetic field, is maintained despite the chaotic evolution of the buoyancy field on a fast timescale by internally driven inertial <span class="hlt">waves</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27652082','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27652082"><span>Flow behind an exponential shock <span class="hlt">wave</span> in a <span class="hlt">rotational</span> axisymmetric perfect gas with magnetic field and variable density.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nath, G; Sahu, P K</p> <p>2016-01-01</p> <p>A self-similar model for one-dimensional unsteady isothermal and adiabatic flows behind a strong exponential shock <span class="hlt">wave</span> driven out by a cylindrical piston moving with time according to an exponential law in an ideal gas in the presence of azimuthal magnetic field and variable density is discussed in a <span class="hlt">rotating</span> atmosphere. The ambient medium is assumed to possess radial, axial and azimuthal component of fluid velocities. The initial density, the fluid velocities and magnetic field of the ambient medium are assumed to be varying with time according to an exponential law. The gas is taken to be non-viscous having infinite electrical conductivity. Solutions are obtained, in both the cases, when the flow between the shock and the piston is isothermal or adiabatic by taking into account the components of vorticity vector. The effects of the variation of the initial density index, adiabatic exponent of the gas and the Alfven-Mach number on the flow-field behind the shock <span class="hlt">wave</span> are investigated. It is found that the presence of the magnetic field have decaying effects on the shock <span class="hlt">wave</span>. Also, it is observed that the effect of an increase in the magnetic field strength is more impressive in the case of adiabatic flow than in the case of isothermal flow. The assumption of zero temperature gradient brings a profound change in the density, non-dimensional azimuthal and axial components of vorticity vector distributions in comparison to those in the case of adiabatic flow. A comparison is made between isothermal and adiabatic flows. It is obtained that an increase in the initial density variation index, adiabatic exponent and strength of the magnetic field decrease the shock strength.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPA....7k5017S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPA....7k5017S"><span>Selective <span class="hlt">wave</span>-transmitting electromagnetic absorber through composite metasurface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Zhiwei; Zhao, Junming; Zhu, Bo; Jiang, Tian; Feng, Yijun</p> <p>2017-11-01</p> <p>Selective <span class="hlt">wave</span>-transmitting absorbers which have one or more narrow transmission bands inside a wide absorption band are often demanded in wireless communication and radome applications for reducing the coupling between different systems, improving anti-jamming capability, and reducing antennas' radar cross section. Here we propose a feasible method that utilizing composite of two metasurfaces with different polarization dependent characteristics, one works as electromagnetic polarization <span class="hlt">rotator</span> and the other as a wideband polarization dependent electromagnetic <span class="hlt">wave</span> absorber. The polarization <span class="hlt">rotator</span> produces a cross polarization output in the <span class="hlt">wave</span>-transmitting band, while preserves the polarization of the incidence outside the band. The metasurface absorber works for certain linear polarization with a much wider absorption band covering the <span class="hlt">wave</span>-transmitting frequency. When combining these two metasurfaces properly, the whole structure behaves as a wideband absorber with a certain frequency transmission window. The proposal may be applied in radome designs to reduce the radar cross section of antenna or improving the electromagnetic compatibility in communication devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012mss..confETH14K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012mss..confETH14K"><span><span class="hlt">Rotational</span> Spectrum of Neopentyl Alcohol, (CH_3)_3CCH_2OH</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kisiel, Zbigniew; Pszczołkowski, Lech; Xue, Zhifeng; Suhm, Martin A.</p> <p>2012-06-01</p> <p>The <span class="hlt">rotational</span> spectrum of neopentyl alcohol (2,2-dimethyl-1-propanol, (CH_3)_3CCH_2OH) has been investigated for the first time. This molecule differs from ethanol only in having the ^tBu group instead of the methyl group, and is likewise anticipated to exhibit two spectroscopic species, with trans and gauche hydroxyl orientation. Quantum chemistry computations predict the trans to be the more stable species. <span class="hlt">Rotational</span> transitions of both species have now been assigned in supersonic expansion cm-<span class="hlt">wave</span> FTMW experiment and in room temperature, mm-<span class="hlt">wave</span> spectra up to 280 GHz. The supersonic expansion measurements with Ar carrier gas confirm that trans is the global minimum species. The trans spectrum is predominantly b-type, while the gauche is predominantly a-type and the frequencies of <span class="hlt">rotational</span> transitions in both species appear to be perturbed in different ways. The results from effective and from coupled Hamiltonian fits for neopentyl alcohol are presented, and are compared with predictions from ab initio calculations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1167455','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/1167455"><span>Ocean floor mounting of <span class="hlt">wave</span> energy converters</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Siegel, Stefan G</p> <p>2015-01-20</p> <p>A system for mounting a set of <span class="hlt">wave</span> energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and <span class="hlt">rotate</span> about the pole. The <span class="hlt">wave</span> energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the <span class="hlt">wave</span> energy converters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JKPS...70..129X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JKPS...70..129X"><span>On the arbitrary l-<span class="hlt">wave</span> solutions of the deformed hyperbolic manning-rosen potential including an improved <span class="hlt">approximation</span> to the orbital centrifugal term</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Chun-Long; Zhang, Min-Cang</p> <p>2017-01-01</p> <p>The arbitrary l-<span class="hlt">wave</span> solutions to the Schrödinger equation for the deformed hyperbolic Manning-Rosen potential is investigated analytically by using the Nikiforov-Uvarov method, the centrifugal term is treated with an improved Greene and Aldrich's <span class="hlt">approximation</span> scheme. The wavefunctions depend on the deformation parameter q, which is expressed in terms of the Jocobi polynomial or the hypergeometric function. The bound state energy is obtained, and the discrete spectrum is shown to be independent of the deformation parameter q.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhFl...29k5105V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhFl...29k5105V"><span>Motion of isolated open vortex filaments evolving under the truncated local induction <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Van Gorder, Robert A.</p> <p>2017-11-01</p> <p>The study of nonlinear <span class="hlt">waves</span> along open vortex filaments continues to be an area of active research. While the local induction <span class="hlt">approximation</span> (LIA) is attractive due to locality compared with the non-local Biot-Savart formulation, it has been argued that LIA appears too simple to model some relevant features of Kelvin <span class="hlt">wave</span> dynamics, such as Kelvin <span class="hlt">wave</span> energy transfer. Such transfer of energy is not feasible under the LIA due to integrability, so in order to obtain a non-integrable model, a truncated LIA, which breaks the integrability of the classical LIA, has been proposed as a candidate model with which to study such dynamics. Recently Laurie et al. ["Interaction of Kelvin <span class="hlt">waves</span> and nonlocality of energy transfer in superfluids," Phys. Rev. B 81, 104526 (2010)] derived truncated LIA systematically from Biot-Savart dynamics. The focus of the present paper is to study the dynamics of a section of common open vortex filaments under the truncated LIA dynamics. We obtain the analog of helical, planar, and more general filaments which <span class="hlt">rotate</span> without a change in form in the classical LIA, demonstrating that while quantitative differences do exist, qualitatively such solutions still exist under the truncated LIA. Conversely, solitons and breather solutions found under the LIA should not be expected under the truncated LIA, as the existence of such solutions relies on the existence of an infinite number of conservation laws which is violated due to loss of integrability. On the other hand, similarity solutions under the truncated LIA can be quite different to their counterparts found for the classical LIA, as they must obey a t1/3 type scaling rather than the t1/2 type scaling commonly found in the LIA and Biot-Savart dynamics. This change in similarity scaling means that Kelvin <span class="hlt">waves</span> are radiated at a slower rate from vortex kinks formed after reconnection events. The loss of soliton solutions and the difference in similarity scaling indicate that dynamics emergent under</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/135617-semiclassical-theory-self-consistent-vibration-rotation-fields-its-application-bending-rotation-interaction-sub-molecule','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/135617-semiclassical-theory-self-consistent-vibration-rotation-fields-its-application-bending-rotation-interaction-sub-molecule"><span>Semiclassical theory of the self-consistent vibration-<span class="hlt">rotation</span> fields and its application to the bending-<span class="hlt">rotation</span> interaction in the H{sub 2}O molecule</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Skalozub, A.S.; Tsaune, A.Ya.</p> <p>1994-12-01</p> <p>A new approach for analyzing the highly excited vibration-<span class="hlt">rotation</span> (VR) states of nonrigid molecules is suggested. It is based on the separation of the vibrational and <span class="hlt">rotational</span> terms in the molecular VR Hamiltonian by introducing periodic auxiliary fields. These fields transfer different interactions within a molecule and are treated in terms of the mean-field <span class="hlt">approximation</span>. As a result, the solution of the stationary Schroedinger equation with the VR Hamiltonian amounts to a quantization of the Berry phase in a problem of the molecular angular-momentum motion in a certain periodic VR field (<span class="hlt">rotational</span> problem). The quantization procedure takes into account themore » motion of the collective vibrational variables in the appropriate VR potentials (vibrational problem). The quantization rules, the mean-field configurations of auxiliary interactions, and the solutions to the Schrodinger equations for the vibrational and <span class="hlt">rotational</span> problems are self-consistently connected with one another. The potentialities of the theory are demonstrated by the bending-<span class="hlt">rotation</span> interaction modeled by the Bunker-Landsberg potential function in the H{sub 2} molecule. The calculations are compared with both the results of the exact computations and those of other <span class="hlt">approximate</span> methods. 32 refs., 4 tabs.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA571540','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA571540"><span>Modeling Wind <span class="hlt">Wave</span> Evolution from Deep to Shallow Water</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2012-09-30</p> <p>WORK COMPLETED Development of a Lumped Quadruplet <span class="hlt">Approximation</span> ( LQA ) A scalable parameterization of non-linear four-<span class="hlt">wave</span> interactions is being...what we refer to as the Lumped Quadruplet <span class="hlt">Approximation</span> ( LQA ), in which discrete contributions on the locus are treated as individual <span class="hlt">wave</span> number...includes inhomogeneous <span class="hlt">wave</span> fields, but is compatible with the action balance generally used in operational <span class="hlt">wave</span> models. RESULTS Development LQA</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22488899-approximation-solution-schrodinger-equation-deformed-rosen-morse-using-supersymmetry-quantum-mechanics-susy-qm','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22488899-approximation-solution-schrodinger-equation-deformed-rosen-morse-using-supersymmetry-quantum-mechanics-susy-qm"><span><span class="hlt">Approximation</span> solution of Schrodinger equation for Q-deformed Rosen-Morse using supersymmetry quantum mechanics (SUSY QM)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Alemgadmi, Khaled I. K., E-mail: azozkied@yahoo.com; Suparmi; Cari</p> <p>2015-09-30</p> <p>The <span class="hlt">approximate</span> analytical solution of Schrodinger equation for Q-Deformed Rosen-Morse potential was investigated using Supersymmetry Quantum Mechanics (SUSY QM) method. The <span class="hlt">approximate</span> bound state energy is given in the closed form and the corresponding <span class="hlt">approximate</span> <span class="hlt">wave</span> function for arbitrary l-state given for ground state <span class="hlt">wave</span> function. The first excited state obtained using upper operator and ground state <span class="hlt">wave</span> function. The special case is given for the ground state in various number of q. The existence of Rosen-Morse potential reduce energy spectra of system. The larger value of q, the smaller energy spectra of system.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhPl...23k2119Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhPl...23k2119Z"><span>Limits of applicability of the quasilinear <span class="hlt">approximation</span> to the electrostatic <span class="hlt">wave</span>-plasma interaction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zacharegkas, Georgios; Isliker, Heinz; Vlahos, Loukas</p> <p>2016-11-01</p> <p>The limitation of the Quasilinear Theory (QLT) to describe the diffusion of electrons and ions in velocity space when interacting with a spectrum of large amplitude electrostatic Langmuir, Upper and Lower hybrid <span class="hlt">waves</span>, is analyzed. We analytically and numerically estimate the threshold for the amplitude of the <span class="hlt">waves</span> above which the QLT breaks down, using a test particle code. The evolution of the velocity distribution, the velocity-space diffusion coefficients, the driven current, and the heating of the particles are investigated, for the interaction with small and large amplitude electrostatic <span class="hlt">waves</span>, that is, in both regimes, where QLT is valid and where it clearly breaks down.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5701374-plasma-waves-near-saturn-initial-results-from-voyager-progress-report','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5701374-plasma-waves-near-saturn-initial-results-from-voyager-progress-report"><span>Plasma <span class="hlt">waves</span> near Saturn: initial results from Voyager 1. Progress report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Gurnett, D.A.; Kurth, W.S.; Scarf, F.L.</p> <p>1981-01-31</p> <p>The Voyager 1 plasma <span class="hlt">wave</span> instrument detected many familiar types of plasma <span class="hlt">waves</span> during the encounter with Saturn, including ion-acoustic <span class="hlt">waves</span> and electron plasma oscillations upstream of the bow shock, an intense burst of electrostatic noise at the shock, and chorus, hiss, electrostatic (n + 1/2)fg <span class="hlt">waves</span> and UHR emissions in the inner magnetosphere. A clock-like Saturn <span class="hlt">rotational</span> control of low-frequency radio emissions was observed, and evidence was obtained of possible control by the moon Dione. Strong plasma <span class="hlt">wave</span> emissions were detected at the Titan encounter indicating the presence of a turbulent sheath extending around Titan, and UHR measurements ofmore » the electron density show the existence of a dense plume of plasma being carried downstream of Titan by the interaction with the rapidly <span class="hlt">rotating</span> magnetosphere of Saturn.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018SuMi..118..152K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018SuMi..118..152K"><span>Four-<span class="hlt">wave</span> mixing in an asymmetric double quantum dot molecule</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kosionis, Spyridon G.</p> <p>2018-06-01</p> <p>The four-<span class="hlt">wave</span> mixing (FWM) effect of a weak probe field, in an asymmetric semiconductor double quantum dot (QD) structure driven by a strong pump field is theoretically studied. Similarly to the case of examining several other nonlinear optical processes, the nonlinear differential equations of the density matrix elements are used, under the <span class="hlt">rotating</span> <span class="hlt">wave</span> <span class="hlt">approximation</span>. By suitably tuning the intensity and the frequency of the pump field as well as by changing the value of the applied bias voltage, a procedure used to properly adjust the electron tunneling coupling, we control the FWM in the same way as several other nonlinear optical processes of the system. While in the weak electron tunneling regime, the impact of the pump field intensity on the FWM is proven to be of crucial importance, for even higher rates of the electron tunneling it is evident that the intensity of the pump field has only a slight impact on the form of the FWM spectrum. The number of the spectral peaks, depends on the relation between specific parameters of the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910007387','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910007387"><span>Distorted-<span class="hlt">wave</span> born <span class="hlt">approximation</span> calculations for turbulence scattering in an upward-refracting atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gilbert, Kenneth E.; Di, Xiao; Wang, Lintao</p> <p>1990-01-01</p> <p>Weiner and Keast observed that in an upward-refracting atmosphere, the relative sound pressure level versus range follows a characteristic 'step' function. The observed step function has recently been predicted qualitatively and quantitatively by including the effects of small-scale turbulence in a parabolic equation (PE) calculation. (Gilbert et al., J. Acoust. Soc. Am. 87, 2428-2437 (1990)). The PE results to single-scattering calculations based on the distorted-<span class="hlt">wave</span> Born <span class="hlt">approximation</span> (DWBA) are compared. The purpose is to obtain a better understanding of the physical mechanisms that produce the step-function. The PE calculations and DWBA calculations are compared to each other and to the data of Weiner and Keast for upwind propagation (strong upward refraction) and crosswind propagation (weak upward refraction) at frequencies of 424 Hz and 848 Hz. The DWBA calculations, which include only single scattering from turbulence, agree with the PE calculations and with the data in all cases except for upwind propagation at 848 Hz. Consequently, it appears that in all cases except one, the observed step function can be understood in terms of single scattering from an upward-refracted 'skywave' into the refractive shadow zone. For upwind propagation at 848 Hz, the DWBA calculation gives levels in the shadow zone that are much below both the PE and the data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.474.5272T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.474.5272T"><span>Towards asteroseismology of core-collapse supernovae with gravitational-<span class="hlt">wave</span> observations - I. Cowling <span class="hlt">approximation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Torres-Forné, Alejandro; Cerdá-Durán, Pablo; Passamonti, Andrea; Font, José A.</p> <p>2018-03-01</p> <p>Gravitational <span class="hlt">waves</span> from core-collapse supernovae are produced by the excitation of different oscillation modes in the protoneutron star (PNS) and its surroundings, including the shock. In this work we study the relationship between the post-bounce oscillation spectrum of the PNS-shock system and the characteristic frequencies observed in gravitational-<span class="hlt">wave</span> signals from core-collapse simulations. This is a fundamental first step in order to develop a procedure to infer astrophysical parameters of the PNS formed in core-collapse supernovae. Our method combines information from the oscillation spectrum of the PNS, obtained through linear perturbation analysis in general relativity of a background physical system, with information from the gravitational-<span class="hlt">wave</span> spectrum of the corresponding non-linear, core-collapse simulation. Using results from the simulation of the collapse of a 35 M⊙ pre-supernova progenitor we show that both types of spectra are indeed related and we are able to identify the modes of oscillation of the PNS, namely g-modes, p-modes, hybrid modes, and standing accretion shock instability (SASI) modes, obtaining a remarkably close correspondence with the time-frequency distribution of the gravitational-<span class="hlt">wave</span> modes. The analysis presented in this paper provides a proof of concept that asteroseismology is indeed possible in the core-collapse scenario, and it may serve as a basis for future work on PNS parameter inference based on gravitational-<span class="hlt">wave</span> observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160005863&hterms=History+Wave+Energy&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DHistory%2BWave%2BEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160005863&hterms=History+Wave+Energy&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DHistory%2BWave%2BEnergy"><span>Quantified Energy Dissipation Rates in the Terrestrial Bow Shock. 2; <span class="hlt">Waves</span> and Dissipation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, L. B., III; Sibeck, D. G.; Breneman, A. W.; Le Contel, O.; Cully, C.; Turner, D. L.; Angelopoulos, V.; Malaspina, D. M.</p> <p>2014-01-01</p> <p>We present the first quantified measure of the energy dissipation rates, due to <span class="hlt">wave</span>-particle interactions, in the transition region of the Earth's collision-less bow shock using data from the Time History of Events and Macro-Scale Interactions during Sub-Storms spacecraft. Our results show that <span class="hlt">wave</span>-particle interactions can regulate the global structure and dominate the energy dissipation of collision-less shocks. In every bow shock crossing examined, we observed both low-frequency (less than 10 hertz) and high-frequency (<span class="hlt">approximately</span> or greater than10 hertz) electromagnetic <span class="hlt">waves</span> throughout the entire transition region and into the magnetosheath. The low-frequency <span class="hlt">waves</span> were consistent with magnetosonic-whistler <span class="hlt">waves</span>. The high-frequency <span class="hlt">waves</span> were combinations of ion-acoustic <span class="hlt">waves</span>, electron cyclotron drift instability driven <span class="hlt">waves</span>, electrostatic solitary <span class="hlt">waves</span>, and whistler mode <span class="hlt">waves</span>. The high-frequency <span class="hlt">waves</span> had the following: (1) peak amplitudes exceeding delta B <span class="hlt">approximately</span> equal to 10 nanoteslas and delta E <span class="hlt">approximately</span> equal to 300 millivolts per meter, though more typical values were delta B <span class="hlt">approximately</span> equal to 0.1-1.0 nanoteslas and delta E <span class="hlt">approximately</span> equal to 10-50 millivolts per meter (2) Poynting fluxes in excess of 2000 microWm(sup -2) (micro-<span class="hlt">waves</span> per square meter) (typical values were <span class="hlt">approximately</span> 1-10 microWm(sup -2) (micro-<span class="hlt">waves</span> per square meter); (3) resistivities greater than 9000 omega meters; and (4) associated energy dissipation rates greater than 10 microWm(sup -3) (micro-<span class="hlt">waves</span> per cubic meter). The dissipation rates due to <span class="hlt">wave</span>-particle interactions exceeded rates necessary to explain the increase in entropy across the shock ramps for <span class="hlt">approximately</span> 90 percent of the <span class="hlt">wave</span> burst durations. For <span class="hlt">approximately</span> 22 percent of these times, the <span class="hlt">wave</span>-particle interactions needed to only be less than or equal to 0.1 percent efficient to balance the nonlinear <span class="hlt">wave</span> steepening that produced the shock <span class="hlt">waves</span>. These results show that <span class="hlt">wave</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950046538&hterms=Pleiades&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DPleiades','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950046538&hterms=Pleiades&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DPleiades"><span><span class="hlt">Rotation</span> periods of open-cluster stars, 3</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Prosser, Charles F.; Shetrone, Matthew D.; Dasgupta, Amil; Backman, Dana E.; Laaksonen, Bentley D.; Baker, Shawn W.; Marschall, Laurence A.; Whitney, Barbara A.; Kuijken, Konrad; Stauffer, John R.</p> <p>1995-01-01</p> <p>We present the results from a photometric monitoring program of 15 open cluster stars and one weak-lined T Tauri star during late 1993/early 1994. Several show <span class="hlt">rotators</span> which are members of the Alpha Persei, Pleiades, and Hyades open clusters have been monitored and period estimates derived. Using all available Pleiades stars with photometric periods together with current X-ray flux measurements, we illustrate the X-ray activity/<span class="hlt">rotation</span> relation among Pleiades late-G/K dwarfs. The data show a clear break in the <span class="hlt">rotation</span>-activity relation around P <span class="hlt">approximately</span> 6-7 days -- in general accordance with previous results using more heterogeneous samples of G/K stars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009APS..DFD.LH002S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009APS..DFD.LH002S"><span>Deformation and <span class="hlt">Rotation</span> of a Drop in a Uniform Electric Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salipante, Paul; Hanna, James; Vlahovska, Petia</p> <p>2009-11-01</p> <p>Drop deformation in uniform electric fields is a classic problem. The pioneering work of G.I.Taylor demonstrated that for weakly conducting media, the drop fluid undergoes a toroidal flow and the drop adopts a prolate or oblate spheroidal shape, the flow and shape being axisymmetrically aligned with the applied field. However, recent studies have revealed a nonaxisymmetric <span class="hlt">rotational</span> mode for drops of lower conductivity than the surrounding medium, similar to the <span class="hlt">rotation</span> of solid dielectric particles observed by Quincke in the 19th century. We will present an experimental and theoretical study of this phenomenon in DC fields. The critical electric field, drop inclination angle, and rate of <span class="hlt">rotation</span> are measured. For small, high viscosity drops, the threshold field strength is well <span class="hlt">approximated</span> by the Quincke <span class="hlt">rotation</span> criterion. Reducing the viscosity ratio shifts the onset for <span class="hlt">rotation</span> to stronger fields. The drop inclination angle increases with field strength. The <span class="hlt">rotation</span> rate is <span class="hlt">approximately</span> given by the inverse Maxwell-Wagner polarization time. We also observe a hysteresis in the tilt angle for low-viscosity drops. The effects of AC fields and surfactants are also explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014isms.confETA08K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014isms.confETA08K"><span>The Mm-<span class="hlt">Wave</span> <span class="hlt">Rotational</span> Spectrum of Glycolic Acid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kisiel, Zbigniew; Pszczółkowski, Lech; Białkowska-Jaworska, Ewa; Charnley, Steven B.</p> <p>2014-06-01</p> <p>Glycolic acid, HOCH_2COOH is the simplest α-hydroxy acid. It is as yet undetected in the interstellar medium, but is known to be present in carbonaceous meteorites and in residues from UV-photolysed interstellar ice analogue mixtures. Prior <span class="hlt">rotational</span> spectroscopy has been carried out up to 40 GHz for the main, SSC conformer, Presently we report the analysis of the <span class="hlt">rotational</span> spectrum of glycolic acid on the basis of broadband measurements performed up to 318 GHz, and updated spectroscopic constants for the ground state and the first two excited states of the low-frequency ν21 torsional mode. We have used the AABS package to assign multiple further excited vibrational states of the SSC conformer. In particular, we have been able to assign the highly perturbed triad of ν14, ν20 and 3ν21 states. The triad has been fitted down to experimental accuracy with a coupled fit, which allowed us to pin down the hitherto elusive frequency of the ν21 mode. The experimental results make an interesting comparison with those of anharmonic force field calculations. We have also been able to extend the measurements for the AAT conformer. C.E.Blom, A.Bauder, Chem. Phys. Lett., 82, 492 (1981), J. Am. Chem. Soc., 104, 2993 (1982). H.Hasegawa, O.Ohashi, I.Yamaguchi, J. Mol. Spectrosc., 82, 205 (1982). P.D.Godfrey, F.M.Rodgers, R.D.Brown, J. Am. Chem. Soc., 119, 2232 (1997).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006CosRe..44..137R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006CosRe..44..137R"><span>On dynamics of a plasma ring <span class="hlt">rotating</span> in the magnetic field of a central body: Magneto-gyroscopic <span class="hlt">waves</span>. Problems of stability and quantization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rabinovich, B. I.</p> <p>2006-03-01</p> <p>Based on a mathematical model described in [1], some new aspects of the dynamics of a thin planar plasma ring <span class="hlt">rotating</span> in the magnetic field of a central body are considered. The dipole field is considered assuming that the dipole has a small eccentricity, and the dipole axis is inclined at a small angle to the central body’s axis of <span class="hlt">rotation</span>. Emphasis is placed on the problem of stability of the ring’s stationary <span class="hlt">rotation</span>. Unlike [1], the disturbed motion is considered which has a character of eddy magneto-gyroscopic <span class="hlt">waves</span>. The original mathematical model is reduced to a system of finite-difference equations whose asymptotic analytical solution is obtained. It is demonstrated that some “elite” rings characterized by integral quantum numbers are long-living, while “lethal” or unstable rings (antirings) are associated with half-integer quantum numbers. As a result, an evolutionally rife <span class="hlt">rotating</span> ring of magnetized plasma turns out to be stratified into a large number of narrow elite rings separated by gaps whose positions correspond to antirings. The regions of possible existence of elite rings in near-central body space are considered. Quantum numbers determining elite eigenvalues of the mean sector velocity (normalized in a certain manner) of a ring coincide with the quantum numbers appearing in the solution to the Schrödinger equation for a hydrogen atom. Perturbations of elite orbits corresponding to these quantum numbers satisfy the de Brogli quantum-mechanical condition. This is one more illustration of the isomorphism of quantization in microcosm and macrocosm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22598978-catastrophic-instabilities-modified-da-dc-hybrid-surface-waves-semi-bounded-plasma-system','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22598978-catastrophic-instabilities-modified-da-dc-hybrid-surface-waves-semi-bounded-plasma-system"><span>Catastrophic instabilities of modified DA-DC hybrid surface <span class="hlt">waves</span> in a semi-bounded plasma system</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lee, Myoung-Jae; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr</p> <p></p> <p>We find the catastrophic instabilities and derive the growth rates for the dust-cyclotron resonance (DCR) and dust-<span class="hlt">rotation</span> resonance (DRR) modes of the modified dust-acoustic and dust-cyclotron (DA-DC) hybrid surface <span class="hlt">waves</span> propagating at the plasma–vacuum interface where the plasma is semi-bounded and composed of electrons and <span class="hlt">rotating</span> dust grains. The effects of magnetic field and dust <span class="hlt">rotation</span> frequency on the DCR- and DDR-modes are also investigated. We find that the dust <span class="hlt">rotation</span> frequency enhances the growth rate of DCR-mode and the effect of dust <span class="hlt">rotation</span> on this resonance mode decreases with an increase of the <span class="hlt">wave</span> number. We also find thatmore » an increase of magnetic field strength enhances the DCR growth rate, especially, for the short wavelength regime. In the case of DRR-mode, the growth rate is found to be decreased less sensitively with an increase of the <span class="hlt">wave</span> number compared with the case of DCR, but much significantly enhanced by an increase of dust <span class="hlt">rotation</span> frequency. The DRR growth rate also decreases with an increase of the magnetic field strength, especially in the long wavelength regime. Interestingly, we find that catastrophic instabilities occur for both DCR- and DRR-modes of the modified DA-DC hybrid surface <span class="hlt">waves</span> when the <span class="hlt">rotational</span> frequency is close to the dust-cyclotron frequency. Both modes can also be excited catastrophically due to the cooperative interaction between the DCR-mode and the DRR-mode.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24730933','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24730933"><span>Zero absolute vorticity: insight from experiments in <span class="hlt">rotating</span> laminar plane Couette flow.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Suryadi, Alexandre; Segalini, Antonio; Alfredsson, P Henrik</p> <p>2014-03-01</p> <p>For pressure-driven turbulent channel flows undergoing spanwise system <span class="hlt">rotation</span>, it has been observed that the absolute vorticity, i.e., the sum of the averaged spanwise flow vorticity and system <span class="hlt">rotation</span>, tends to zero in the central region of the channel. This observation has so far eluded a convincing theoretical explanation, despite experimental and numerical evidence reported in the literature. Here we show experimentally that three-dimensional laminar structures in plane Couette flow, which appear under anticyclonic system <span class="hlt">rotation</span>, give the same effect, namely, that the absolute vorticity tends to zero if the <span class="hlt">rotation</span> rate is high enough. It is shown that this is equivalent to a local Richardson number of <span class="hlt">approximately</span> zero, which would indicate a stable condition. We also offer an explanation based on Kelvin's circulation theorem to demonstrate that the absolute vorticity should remain constant and <span class="hlt">approximately</span> equal to zero in the central region of the channel when going from the nonrotating fully turbulent state to any state with sufficiently high <span class="hlt">rotation</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870016952','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870016952"><span>Finite element analysis of flexible, <span class="hlt">rotating</span> blades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcgee, Oliver G.</p> <p>1987-01-01</p> <p>A reference guide that can be used when using the finite element method to <span class="hlt">approximate</span> the static and dynamic behavior of flexible, <span class="hlt">rotating</span> blades is given. Important parameters such as twist, sweep, camber, co-planar shell elements, centrifugal loads, and inertia properties are studied. Comparisons are made between NASTRAN elements through published benchmark tests. The main purpose is to summarize blade modeling strategies and to document capabilities and limitations (for flexible, <span class="hlt">rotating</span> blades) of various NASTRAN elements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120002758','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120002758"><span>Tropical Cyclogenesis in a Tropical <span class="hlt">Wave</span> Critical Layer: Easterly <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dunkerton, T. J.; Montgomery, M. T.; Wang, Z.</p> <p>2009-01-01</p> <p>The development of tropical depressions within tropical <span class="hlt">waves</span> over the Atlantic and eastern Pacific is usually preceded by a "surface low along the <span class="hlt">wave</span>" as if to suggest a hybrid <span class="hlt">wave</span>-vortex structure in which flow streamlines not only undulate with the <span class="hlt">waves</span>, but form a closed circulation in the lower troposphere surrounding the low. This structure, equatorward of the easterly jet axis, is identified herein as the familiar critical layer of <span class="hlt">waves</span> in shear flow, a flow configuration which arguably provides the simplest conceptual framework for tropical cyclogenesis resulting from tropical <span class="hlt">waves</span>, their interaction with the mean flow, and with diabatic processes associated with deep moist convection. The recirculating Kelvin cat's eye within the critical layer represents a sweet spot for tropical cyclogenesis in which a proto-vortex may form and grow within its parent <span class="hlt">wave</span>. A common location for storm development is given by the intersection of the <span class="hlt">wave</span>'s critical latitude and trough axis at the center of the cat's eye, with analyzed vorticity centroid nearby. The <span class="hlt">wave</span> and vortex live together for a time, and initially propagate at <span class="hlt">approximately</span> the same speed. In most cases this coupled propagation continues for a few days after a tropical depression is identified. For easterly <span class="hlt">waves</span>, as the name suggests, the propagation is westward. It is shown that in order to visualize optimally the associated Lagrangian motions, one should view the flow streamlines, or stream function, in a frame of reference translating horizontally with the phase propagation of the parent <span class="hlt">wave</span>. In this co-moving frame, streamlines are <span class="hlt">approximately</span> equivalent to particle trajectories. The closed circulation is quasi-stationary, and a dividing streamline separates air within the cat's eye from air outside.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020081295&hterms=traveling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dtraveling','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020081295&hterms=traveling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dtraveling"><span>Solar Supergranulation Revealed as a Superposition of Traveling <span class="hlt">Waves</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gizon, L.; Duvall, T. L., Jr.; Schou, J.; Oegerle, William (Technical Monitor)</p> <p>2002-01-01</p> <p>40 years ago two new solar phenomena were described: supergranulation and the five-minute solar oscillations. While the oscillations have since been explained and exploited to determine the properties of the solar interior, the supergranulation has remained unexplained. The supergranules, appearing as convective-like cellular patterns of horizontal outward flow with a characteristic diameter of 30 Mm and an apparent lifetime of 1 day, have puzzling properties, including their apparent superrotation and the minute temperature variations over the cells. Using a 60-day sequence of data from the MDI (Michelson-Doppler Imager) instrument onboard the SOHO (Solar and Heliospheric Observatory) spacecraft, we show that the supergranulation pattern is formed by a superposition of traveling <span class="hlt">waves</span> with periods of 5-10 days. The <span class="hlt">wave</span> power is anisotropic with excess power in the direction of <span class="hlt">rotation</span> and toward the equator, leading to spurious <span class="hlt">rotation</span> rates and north-south flows as derived from correlation analyses. These newly discovered <span class="hlt">waves</span> could play an important role in maintaining differential <span class="hlt">rotation</span> in the upper convection zone by transporting angular momentum towards the equator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22596852-coherent-distributions-rigid-rotator','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22596852-coherent-distributions-rigid-rotator"><span>Coherent distributions for the rigid <span class="hlt">rotator</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Grigorescu, Marius</p> <p>2016-06-15</p> <p>Coherent solutions of the classical Liouville equation for the rigid <span class="hlt">rotator</span> are presented as positive phase-space distributions localized on the Lagrangian submanifolds of Hamilton-Jacobi theory. These solutions become Wigner-type quasiprobability distributions by a formal discretization of the left-invariant vector fields from their Fourier transform in angular momentum. The results are consistent with the usual quantization of the anisotropic <span class="hlt">rotator</span>, but the expected value of the Hamiltonian contains a finite “zero point” energy term. It is shown that during the time when a quasiprobability distribution evolves according to the Liouville equation, the related quantum <span class="hlt">wave</span> function should satisfy the time-dependent Schrödingermore » equation.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AIPC.1953l0024V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AIPC.1953l0024V"><span>Opening and closing of band gaps in magnonic waveguide by <span class="hlt">rotating</span> the triangular antidots - A micromagnetic study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vivek, T.; Bhoomeeswaran, H.; Sabareesan, P.</p> <p>2018-05-01</p> <p>Spin <span class="hlt">waves</span> in ID periodic triangular array of antidots are encarved in a permalloy magnonic waveguide is investigated through micromagnetic simulation. The effect of the <span class="hlt">rotating</span> array of antidots and in-plane <span class="hlt">rotation</span> of the scattering centers on the band structure are investigated, to indicate new possibilities of fine tuning of spin-<span class="hlt">wave</span> filter pass and stop bands. The results show that, the opening and closing of band gaps paves a way for band pass and stop filters on waveguide. From the results, the scattering center and strong spatial distribution field plays crucible role for controlling opening and closing bandgap width of ˜12 GHz for 0° <span class="hlt">rotation</span>. We have obtained a single narrow bandgap of width 1GHz is obtained for 90° <span class="hlt">rotation</span> of the antidot. Similarly, the tunability is achieved for desired microwave applications done by <span class="hlt">rotating</span> triangular antidots with different orientation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA609448','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA609448"><span>T sub 1-echo sequence: Protecting the State of a Qubit in the Presence of Coherent Interaction</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2012-09-25</p> <p>memory is at energy m, and they are coupled with a coupling strength v⊥. We write the coupling in the <span class="hlt">rotating</span> - <span class="hlt">wave</span> <span class="hlt">approximation</span> , assuming q,m...important for the time evolution. In the validity range of the <span class="hlt">rotating</span> - <span class="hlt">wave</span> <span class="hlt">approximation</span> , the above Hamiltonian preserves the total number of...excited state) in total is involved in the dynamics, the underlying Jaynes - Cummings Hamiltonian will lead to the same results as the ones presented here</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatAs.tmp...57J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatAs.tmp...57J"><span>Evidence of a plume on Europa from Galileo magnetic and plasma <span class="hlt">wave</span> signatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jia, Xianzhe; Kivelson, Margaret G.; Khurana, Krishan K.; Kurth, William S.</p> <p>2018-05-01</p> <p>The icy surface of Jupiter's moon, Europa, is thought to lie on top of a global ocean1-4. Signatures in some Hubble Space Telescope images have been associated with putative water plumes rising above Europa's surface5,6, providing support for the ocean theory. However, all telescopic detections reported were made at the limit of sensitivity of the data5-7, thereby calling for a search for plume signatures in in-situ measurements. Here, we report in-situ evidence of a plume on Europa from the magnetic field and plasma <span class="hlt">wave</span> observations acquired on Galileo's closest encounter with the moon. During this flyby, which dropped below 400 km altitude, the magnetometer8 recorded an <span class="hlt">approximately</span> 1,000-kilometre-scale field <span class="hlt">rotation</span> and a decrease of over 200 nT in field magnitude, and the Plasma <span class="hlt">Wave</span> Spectrometer9 registered intense localized <span class="hlt">wave</span> emissions indicative of a brief but substantial increase in plasma density. We show that the location, duration and variations of the magnetic field and plasma <span class="hlt">wave</span> measurements are consistent with the interaction of Jupiter's corotating plasma with Europa if a plume with characteristics inferred from Hubble images were erupting from the region of Europa's thermal anomalies. These results provide strong independent evidence of the presence of plumes at Europa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatAs...2..459J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatAs...2..459J"><span>Evidence of a plume on Europa from Galileo magnetic and plasma <span class="hlt">wave</span> signatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jia, Xianzhe; Kivelson, Margaret G.; Khurana, Krishan K.; Kurth, William S.</p> <p>2018-06-01</p> <p>The icy surface of Jupiter's moon, Europa, is thought to lie on top of a global ocean1-4. Signatures in some Hubble Space Telescope images have been associated with putative water plumes rising above Europa's surface5,6, providing support for the ocean theory. However, all telescopic detections reported were made at the limit of sensitivity of the data5-7, thereby calling for a search for plume signatures in in-situ measurements. Here, we report in-situ evidence of a plume on Europa from the magnetic field and plasma <span class="hlt">wave</span> observations acquired on Galileo's closest encounter with the moon. During this flyby, which dropped below 400 km altitude, the magnetometer8 recorded an <span class="hlt">approximately</span> 1,000-kilometre-scale field <span class="hlt">rotation</span> and a decrease of over 200 nT in field magnitude, and the Plasma <span class="hlt">Wave</span> Spectrometer9 registered intense localized <span class="hlt">wave</span> emissions indicative of a brief but substantial increase in plasma density. We show that the location, duration and variations of the magnetic field and plasma <span class="hlt">wave</span> measurements are consistent with the interaction of Jupiter's corotating plasma with Europa if a plume with characteristics inferred from Hubble images were erupting from the region of Europa's thermal anomalies. These results provide strong independent evidence of the presence of plumes at Europa.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Ap%26SS.355..233J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Ap%26SS.355..233J"><span>Electron acoustic solitons in magneto-<span class="hlt">rotating</span> electron-positron-ion plasma with nonthermal electrons and positrons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jilani, K.; Mirza, Arshad M.; Iqbal, J.</p> <p>2015-02-01</p> <p>The propagation of electron acoustic solitary <span class="hlt">waves</span> (EASWs) in a magneto-<span class="hlt">rotating</span> electron-positron-ion (epi) plasma containing cold dynamical electrons, nonthermal electrons and positrons obeying Cairns' distribution have been explored in the stationary background of massive positive ions. Through the linear dispersion relation (LDR) the effects of nonthermal components, magnetic field and <span class="hlt">rotation</span> have been analyzed, wherein, various limiting cases have been deduced from the LDR. For nonlinear analysis, Korteweg-de Vries (KdV) equation is obtained using the reductive perturbation technique. It is found that in the presence of nonthermal positrons both hump and dip type solitons appear to excite, the structural properties of these solitary <span class="hlt">waves</span> change drastically with magneto-<span class="hlt">rotating</span> effects. The present work may be employed to explore and to understand the formation of electron acoustic solitary structures in the space and laboratory plasmas with nonthermal electrons and positrons under magneto-<span class="hlt">rotating</span> effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999DyAtO..29...65P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999DyAtO..29...65P"><span>Internal <span class="hlt">waves</span> and rectification in a linearly stratified fluid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pérenne, Nicolas; Renouard, Dominique P.</p> <p></p> <p>Laboratory experiments were performed in a 13-m diameter <span class="hlt">rotating</span> tank equipped with a continuous shelf break geometry and a central piston-like plunger. The fluid density was linearly stratified. The amplitude and period of the plunger, the <span class="hlt">rotation</span> rate of the platform and the stratification are the parameters of the problem. The density fluctuations at six stations above and at mid-depth of the slope, along with dye visualization of the flow, were recorded. A limited set of experiments showed that a barotropic periodical forcing generated a first mode baroclinic <span class="hlt">wave</span> which initially appears at the slope and propagates offshore. The likely presence of internal energy rays either slightly above, or immediately along the slope, is in agreement with previous analytical, laboratory and selected oceanic observations. In the former case, the stratification was such that the slope flow at mid-depth was supercritical while in the latter case, slope flow at mid-depth was critical. <span class="hlt">Rotation</span> tended to decrease the amplitude of the generated internal <span class="hlt">wave</span>. Also, non-linear processes were likely to act upon these <span class="hlt">waves</span> for their normalized amplitude tended to decrease as the forcing increased (for similar forcing period, <span class="hlt">rotation</span> rate and stratification). After the internal <span class="hlt">wave</span> reflected from the plunger reaches the slope, there is a complex non-stationary regime with an occurrence of internal <span class="hlt">wave</span> breaking in the vicinity of the slope. Thus there was an appearance of localized patches of turbulence and mixing. These events appeared both in dye visualization and in density fluctuations records. The subsequent mixing, or else the combined effect of topographical rectification and mixing, led to the appearance of a distinct Lagrangian transport, localized in the first few centimeters above the slope and oriented so as to leave the shallow waters on the right of its displacement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSA21A2502C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSA21A2502C"><span>Faraday <span class="hlt">rotation</span> of Automatic Dependent Surveillance Broadcast (ADS-B) signals as a method of ionospheric characterization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cushley, A. C.; Kabin, K.; Noel, J. M. A.</p> <p>2017-12-01</p> <p>Radio <span class="hlt">waves</span> propagating through plasma in the Earth's ambient magnetic field experience Faraday <span class="hlt">rotation</span>; the plane of the electric field of a linearly polarized <span class="hlt">wave</span> changes as a function of the distance travelled through a plasma. Linearly polarized radio <span class="hlt">waves</span> at 1090 MHz frequency are emitted by Automatic Dependent Surveillance Broadcast (ADS-B) devices which are installed on most commercial aircraft. These radio <span class="hlt">waves</span> can be detected by satellites in low earth orbits, and the change of the polarization angle caused by propagation through the terrestrial ionosphere can be measured. In this work we discuss how these measurements can be used to characterize the ionospheric conditions. In the present study, we compute the amount of Faraday <span class="hlt">rotation</span> from a prescribed total electron content value and two of the profile parameters of the NeQuick model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA483154','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA483154"><span>Evaluation of an <span class="hlt">Approximate</span> Method for Incorporating Floating Docks in Harbor <span class="hlt">Wave</span> Prediction Models</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2005-11-25</p> <p>fact, Koutandos et al. (2004) even now have had to limit their work only to the x–z plane while using a similar approach. In this paper, therefore, we...breakwater Koutandos et al. (2004) have presented data pertaining to transmission coefficients for <span class="hlt">waves</span> passing a fixed, infinitely long, floating...4. Values of A and B for determining α. Fig. 5. <span class="hlt">Wave</span> height comparison with data presented in Koutandos et al. (2004). Fig. 6. <span class="hlt">Wave</span> transmission past</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9252E..02A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9252E..02A"><span>Millimeter <span class="hlt">wave</span> radar system on a <span class="hlt">rotating</span> platform for combined search and track functionality with SAR imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aulenbacher, Uwe; Rech, Klaus; Sedlmeier, Johannes; Pratisto, Hans; Wellig, Peter</p> <p>2014-10-01</p> <p>Ground based millimeter <span class="hlt">wave</span> radar sensors offer the potential for a weather-independent automatic ground surveillance at day and night, e.g. for camp protection applications. The basic principle and the experimental verification of a radar system concept is described, which by means of an extreme off-axis positioning of the antenna(s) combines azimuthal mechanical beam steering with the formation of a circular-arc shaped synthetic aperture (SA). In automatic ground surveillance the function of search and detection of moving ground targets is performed by means of the conventional mechanical scan mode. The <span class="hlt">rotated</span> antenna structure designed as a small array with two or more RX antenna elements with simultaneous receiver chains allows to instantaneous track multiple moving targets (monopulse principle). The simultaneously operated SAR mode yields areal images of the distribution of stationary scatterers. For ground surveillance application this SAR mode is best suited for identifying possible threats by means of change detection. The feasibility of this concept was tested by means of an experimental radar system comprising of a 94 GHz (W band) FM-CW module with 1 GHz bandwidth and two RX antennas with parallel receiver channels, placed off-axis at a <span class="hlt">rotating</span> platform. SAR mode and search/track mode were tested during an outdoor measurement campaign. The scenery of two persons walking along a road and partially through forest served as test for the capability to track multiple moving targets. For SAR mode verification an image of the area composed of roads, grassland, woodland and several man-made objects was reconstructed from the measured data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26066112','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26066112"><span><span class="hlt">Wave</span>-packet formation at the zero-dispersion point in the Gardner-Ostrovsky equation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Whitfield, A J; Johnson, E R</p> <p>2015-05-01</p> <p>The long-time effect of weak <span class="hlt">rotation</span> on an internal solitary <span class="hlt">wave</span> is the decay into inertia-gravity <span class="hlt">waves</span> and the eventual emergence of a coherent, steadily propagating, nonlinear <span class="hlt">wave</span> packet. There is currently no entirely satisfactory explanation as to why these <span class="hlt">wave</span> packets form. Here the initial value problem is considered within the context of the Gardner-Ostrovsky, or <span class="hlt">rotation</span>-modified extended Korteweg-de Vries, equation. The linear Gardner-Ostrovsky equation has maximum group velocity at a critical <span class="hlt">wave</span> number, often called the zero-dispersion point. It is found here that a nonlinear splitting of the <span class="hlt">wave</span>-number spectrum at the zero-dispersion point, where energy is shifted into the modulationally unstable regime of the Gardner-Ostrovsky equation, is responsible for the <span class="hlt">wave</span>-packet formation. Numerical comparisons of the decay of a solitary <span class="hlt">wave</span> in the Gardner-Ostrovsky equation and a derived nonlinear Schrödinger equation at the zero-dispersion point are used to confirm the spectral splitting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2252835R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2252835R"><span>Two-dimensional models of fast <span class="hlt">rotating</span> early-type stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rieutord, Michel</p> <p>2015-08-01</p> <p><span class="hlt">Rotation</span> has now become an unavoidable parameter of stellar models, but for most massive or intermediate-mass stars <span class="hlt">rotation</span> is fast, at least of a significant fraction of the critical angular velocity. Current spherically symmetric models try to cope with this feature of the stars using various <span class="hlt">approximations</span>, like for instance the so-called shellular <span class="hlt">rotation</span> usually accompanied with a diffusion that is meant to represent the mixing induced by <span class="hlt">rotationally</span> generated flows. Such <span class="hlt">approximations</span> may be justified in the limit of slow <span class="hlt">rotation</span> where anisotropies and associated flows are weak. However, when <span class="hlt">rotation</span> is fast, say larger than 50% of the critical velocities the use of a spherically symmetric 1D-model is doubtful. This is not only because of the centrifugal flattening of the star, but also because of the flows that are induced by the baroclinic torque that naturally appears in the radiative envelope of an early-type (<span class="hlt">rotating</span>) star. These flows face the cylindrical symmetry of the Coriolis force and the spheroidal symmetry of the effective gravity.In this talk I shall present the latest results of the ESTER project that has taken up the challenge of making two-dimensional (axisymmetric) models of stars <span class="hlt">rotating</span> at any <span class="hlt">rotation</span> rate. In particular, I will focus on main sequence massive and intermediate-mass stars. I'll show what should be expected in such stars as far as the differential <span class="hlt">rotation</span> and the associated meridional circulation are concerned, notably the emergence of a Stewartson layer along the tangential cylinder of the core. I'll also indicate what may be inferred about the evolution of an intermediate-mass star at constant angular momentum and how Be stars may form. I shall finally give some comparisons between models and observations of the gravity darkening on some nearby fast <span class="hlt">rotators</span> as it has been derived from interferometric observations. In passing, I'll also discuss how 2D models can help to recover the fundamental parameters of a star.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/865388','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/865388"><span><span class="hlt">Rotatable</span> superconducting cyclotron adapted for medical use</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Blosser, Henry G.; Johnson, David A.; Riedel, Jack; Burleigh, Richard J.</p> <p>1985-01-01</p> <p>A superconducting cyclotron (10) <span class="hlt">rotatable</span> on a support structure (11) in an arc of about 180.degree. around a pivot axis (A--A) and particularly adapted for medical use is described. The <span class="hlt">rotatable</span> support structure (13, 15) is balanced by being counterweighted (14) so as to allow <span class="hlt">rotation</span> of the cyclotron and a beam (12), such as a subparticle (neutron) or atomic particle beam, from the cyclotron in the arc around a patient. Flexible hose (25) is moveably attached to the support structure for providing a liquified gas which is supercooled to near 0.degree. K. to an inlet means (122) to a chamber (105) around superconducting coils (101, 102). The liquid (34) level in the cyclotron is maintained <span class="hlt">approximately</span> half full so that <span class="hlt">rotation</span> of the support structure and cyclotron through the 180.degree. can be accomplished without spilling the liquid from the cyclotron. With the coils vertically oriented, each turn of the winding is <span class="hlt">approximately</span> half immersed in liquid (34) and half exposed to cold gas and adequate cooling to maintain superconducting temperatures in the section of coil above the liquid level is provided by the combination of cold gas/vapor and by the conductive flow of heat along each turn of the winding from the half above the liquid to the half below.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MNRAS.477.1383B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MNRAS.477.1383B"><span>Triaxial instabilities in rapidly <span class="hlt">rotating</span> neutron stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Basak, Arkadip</p> <p>2018-06-01</p> <p>Viscosity driven bar mode secular instabilities of rapidly <span class="hlt">rotating</span> neutron stars are studied using LORENE/Nrotstar code. These instabilities set a more rigorous limit to the <span class="hlt">rotation</span> frequency of a neutron star than the Kepler frequency/mass-shedding limit. The procedure employed in the code comprises of perturbing an axisymmetric and stationary configuration of a neutron star and studying its evolution by constructing a series of triaxial quasi-equilibrium configurations. Symmetry breaking point was found out for Polytropic as well as 10 realistic equations of states (EOS) from the CompOSE data base. The concept of piecewise polytropic EOSs has been used to comprehend the <span class="hlt">rotational</span> instability of Realistic EOSs and validated with 19 different Realistic EOSs from CompOSE. The possibility of detecting quasi-periodic gravitational <span class="hlt">waves</span> from viscosity driven instability with ground-based LIGO/VIRGO interferometers is also discussed very briefly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820061054&hterms=SPIRAL+MODEL&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSPIRAL%2BMODEL','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820061054&hterms=SPIRAL+MODEL&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSPIRAL%2BMODEL"><span>The structure and evolution of galacto-detonation <span class="hlt">waves</span> - Some analytic results in sequential star formation models of spiral galaxies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cowie, L. L.; Rybicki, G. B.</p> <p>1982-01-01</p> <p><span class="hlt">Waves</span> of star formation in a uniform, differentially <span class="hlt">rotating</span> disk galaxy are treated analytically as a propagating detonation <span class="hlt">wave</span> front. It is shown, that if single solitary <span class="hlt">waves</span> could be excited, they would evolve asymptotically to one of two stable spiral forms, each of which <span class="hlt">rotates</span> with a fixed pattern speed. Simple numerical solutions confirm these results. However, the pattern of <span class="hlt">waves</span> that develop naturally from an initially localized disturbance is more complex and dies out within a few <span class="hlt">rotation</span> periods. These results suggest a conclusive observational test for deciding whether sequential star formation is an important determinant of spiral structure in some class of galaxies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004cosp...35..913K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004cosp...35..913K"><span>Terrestrial Planets: Volatiles Loss & Speed of <span class="hlt">Rotation</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kochemasov, G. G.</p> <p></p> <p>There is a close relation between orbiting frequencies of terrestrial planets and intensities of their outgassing [1]. ``Sweeping'' out volatiles of their bodies is provoked and facilitated by body shaking (<span class="hlt">wave</span> oscillations) caused by movement of celestial bodies in elliptical orbits. Non-round orbits cause inertia-gravity warpings in all spheres of the bodies producing their tectonic granulation. The higher orbiting frequency -- the smaller tectonic granula -- more thorough interior degassing. Sizes of tectonic granulas inversely proportional to orbiting frequencies are: Mars π R/2, Earth π R/4, Venus π R/6, Mercury π R/16. The atmospheric masses increase from Mars through Earth to Venus as ˜ 0. 01 : 1 : 90 (radiogenic/primordial Ar is 3000 : 300 : 1, marking degassing intensity). Mercury in this sequence should have been even more outgassed (˜ 500 times comparative to Venus, having in mind different planetary masses [2]). But now it possesses only very weak atmosphere of noble gases, Na, K -- remnants of past significant outgassing now witnessed by a great amount of small deep structurally controlled pits (craters), lobate scarps caused by strong contraction and slow <span class="hlt">rotation</span>. The slow <span class="hlt">rotation</span> is due to loss of angular momentum to the atmosphere now wiped out by the solar wind. The same partitioning of angular momentum occurs at Venus: slowly <span class="hlt">rotating</span> solid body is wrapped in rapidly <span class="hlt">rotating</span> massive atmosphere (the solid surface exposes many features of contraction due to subsidence -- vast areas of wrinkle ridges). On the contrary to slow Mercury and Venus, Earth and Mars keep their moderate <span class="hlt">rotation</span> corresponding to their moderate and mild degassing [3]. Still further from Sun weakly outgassed gas giants <span class="hlt">rotate</span> very rapidly. Sun itself with slowly <span class="hlt">rotating</span> photosphere and corresponding supergranula size π R/60 is a strongly outgassed object (some think that Sun lost upto 10% of its original mass). In line with the established regularity between</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5859379','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5859379"><span>Real-Time <span class="hlt">Rotational</span> Activity Detection in Atrial Fibrillation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ríos-Muñoz, Gonzalo R.; Arenal, Ángel; Artés-Rodríguez, Antonio</p> <p>2018-01-01</p> <p><span class="hlt">Rotational</span> activations, or spiral <span class="hlt">waves</span>, are one of the proposed mechanisms for atrial fibrillation (AF) maintenance. We present a system for assessing the presence of <span class="hlt">rotational</span> activity from intracardiac electrograms (EGMs). Our system is able to operate in real-time with multi-electrode catheters of different topologies in contact with the atrial wall, and it is based on new local activation time (LAT) estimation and <span class="hlt">rotational</span> activity detection methods. The EGM LAT estimation method is based on the identification of the highest sustained negative slope of unipolar signals. The method is implemented as a linear filter whose output is interpolated on a regular grid to match any catheter topology. Its operation is illustrated on selected signals and compared to the classical Hilbert-Transform-based phase analysis. After the estimation of the LAT on the regular grid, the detection of <span class="hlt">rotational</span> activity in the atrium is done by a novel method based on the optical flow of the wavefront dynamics, and a <span class="hlt">rotation</span> pattern match. The methods have been validated using in silico and real AF signals. PMID:29593566</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017A%26A...598A...9B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017A%26A...598A...9B"><span>Laboratory detection of the <span class="hlt">rotational</span>-tunnelling spectrum of the hydroxymethyl radical, CH2OH</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bermudez, C.; Bailleux, S.; Cernicharo, J.</p> <p>2017-02-01</p> <p>Context. Of the two structural isomers of CH3O, methoxy is the only radical whose astronomical detection has been reported through the observation of several <span class="hlt">rotational</span> lines at 2 and 3 mm wavelengths. Although the hydroxymethyl radical, CH2OH, is known to be thermodynamically the most stable (by 3300 cm-1), it has so far eluded <span class="hlt">rotational</span> spectroscopy presumably because of its high chemical reactivity. Aims: Recent high-resolution ( 10 MHz) sub-Doppler rovibrationally resolved infrared spectra of CH2OH (symmetric CH stretching a-type band) provided accurate ground vibrational state <span class="hlt">rotational</span> constants, thus reviving the quest for its millimeter-<span class="hlt">wave</span> spectrum in laboratory and subsequently in space. Methods: The search and assignment of the <span class="hlt">rotational</span> spectrum of this fundamental species were guided by our quantum chemical calculations and by using <span class="hlt">rotational</span> constants derived from high-resolution IR data. The hydroxymethyl radical was produced by hydrogen abstraction from methanol by atomic chlorine. Results: Ninety-six b-type <span class="hlt">rotational</span> transitions between the v = 0 and v = 1 tunnelling sublevels involving 25 fine-structure components of Q branches (with Ka = 1 ← 0) and 4 fine-structure components of R branches (assigned to Ka = 0 ← 1) were measured below 402 GHz. Hyperfine structure alternations due to the two identical methylenic hydrogens were observed and analysed based on the symmetry and parity of the <span class="hlt">rotational</span> levels. A global fit including infrared and millimeter-<span class="hlt">wave</span> lines has been conducted using Pickett's reduced axis system Hamiltonian. The recorded transitions (odd ΔKa) did not allow us to evaluate the Coriolis tunnelling interaction term. The comparison of the experimentally determined constants for both tunnelling levels with their computed values secures the long-awaited first detection of the <span class="hlt">rotational</span>-tunnelling spectrum of this radical. In particular, a tunnelling rate of 139.73 ± 0.10 MHz (4.6609(32) × 10-3 cm-1) was obtained along</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985DyAtO...9...85G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985DyAtO...9...85G"><span>The reflection and diffraction of internal <span class="hlt">waves</span> from the junction of a slit and a half-space, with application to submarine canyons</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grimshaw, R. H. J.; Baines, P. G.; Bell, R. C.</p> <p>1985-07-01</p> <p>We consider the three-dimensional reflection and diffraction properties of internal <span class="hlt">waves</span> in a continuously stratified <span class="hlt">rotating</span> fluid which are incident on the junction of a vertical slit and a half-space. This geometry is a model for submarine canyons on continental slopes in the ocean, where various physical phenomena embodying reflection and diffraction effects have been observed. Three types of incident <span class="hlt">wave</span> are considered: (1) Kelvin <span class="hlt">waves</span> in the slit (canyon); (2) Kelvin <span class="hlt">waves</span> on the slope; and (3) plane internal <span class="hlt">waves</span> incident from the half-space (ocean). These are scattered into Kelvin and Poincaré <span class="hlt">waves</span> in the slit, a Kelvin <span class="hlt">wave</span> on the slope and Poincaré <span class="hlt">waves</span> in the half-space. Most of the discussion is centered around case (1). Various properties of the <span class="hlt">wave</span> field are calculated for ranges of the parameters c/ cot θ, γα and ƒ/ω where cot θ is the topographic slope, c is the internal <span class="hlt">wave</span> ray slope, α is the canyon half-width, γ is the down-slope <span class="hlt">wave</span>-number, ƒ is the Coriolis parameter and ω is the <span class="hlt">wave</span> frequency. Analytical results are obtained for small γα and some <span class="hlt">approximate</span> results for larger values of γα. The results show that significant <span class="hlt">wave</span> trapping may occur in oceanic situations, and that submarine canyons may act as source regions for internal Kelvin <span class="hlt">waves</span> on the continental slope.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995OptL...20..270A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995OptL...20..270A"><span>Soliton polarization <span class="hlt">rotation</span> in fiber lasers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Afanasjev, V. V.</p> <p>1995-02-01</p> <p>I have found the <span class="hlt">approximate</span> analytical solution in explicit form for a vector soliton with an arbitrary component ratio. My solution describes the dependence of soliton intensity on polarization angle and also nonlinear polarization <span class="hlt">rotation</span>. The analytical results agree well with the numerical simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26509428','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26509428"><span>Photoelectron <span class="hlt">wave</span> function in photoionization: plane <span class="hlt">wave</span> or Coulomb <span class="hlt">wave</span>?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gozem, Samer; Gunina, Anastasia O; Ichino, Takatoshi; Osborn, David L; Stanton, John F; Krylov, Anna I</p> <p>2015-11-19</p> <p>The calculation of absolute total cross sections requires accurate <span class="hlt">wave</span> functions of the photoelectron and of the initial and final states of the system. The essential information contained in the latter two can be condensed into a Dyson orbital. We employ correlated Dyson orbitals and test <span class="hlt">approximate</span> treatments of the photoelectron <span class="hlt">wave</span> function, that is, plane and Coulomb <span class="hlt">waves</span>, by comparing computed and experimental photoionization and photodetachment spectra. We find that in anions, a plane <span class="hlt">wave</span> treatment of the photoelectron provides a good description of photodetachment spectra. For photoionization of neutral atoms or molecules with one heavy atom, the photoelectron <span class="hlt">wave</span> function must be treated as a Coulomb <span class="hlt">wave</span> to account for the interaction of the photoelectron with the +1 charge of the ionized core. For larger molecules, the best agreement with experiment is often achieved by using a Coulomb <span class="hlt">wave</span> with a partial (effective) charge smaller than unity. This likely derives from the fact that the effective charge at the centroid of the Dyson orbital, which serves as the origin of the spherical <span class="hlt">wave</span> expansion, is smaller than the total charge of a polyatomic cation. The results suggest that accurate molecular photoionization cross sections can be computed with a modified central potential model that accounts for the nonspherical charge distribution of the core by adjusting the charge in the center of the expansion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26871082','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26871082"><span>Phase-locked scroll <span class="hlt">waves</span> defy turbulence induced by negative filament tension.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Teng-Chao; Gao, Xiang; Zheng, Fei-Fei; Cai, Mei-Chun; Li, Bing-Wei; Zhang, Hong; Dierckx, Hans</p> <p>2016-01-01</p> <p>Scroll <span class="hlt">waves</span> in a three-dimensional media may develop into turbulence due to negative tension of the filament. Such negative tension-induced instability of scroll <span class="hlt">waves</span> has been observed in the Belousov-Zhabotinsky reaction systems. Here we propose a method to restabilize scroll <span class="hlt">wave</span> turbulence caused by negative tension in three-dimensional chemical excitable media using a circularly polarized (<span class="hlt">rotating</span>) external field. The stabilization mechanism is analyzed in terms of phase-locking caused by the external field, which makes the effective filament tension positive. The phase-locked scroll <span class="hlt">waves</span> that have positive tension and higher frequency defy the turbulence and finally restore order. A linear theory for the change of filament tension caused by a generic <span class="hlt">rotating</span> external field is presented and its predictions closely agree with numerical simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19258914','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19258914"><span><span class="hlt">Approximating</span> lens power.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaye, Stephen B</p> <p>2009-04-01</p> <p>To provide a scalar measure of refractive error, based on geometric lens power through principal, orthogonal and oblique meridians, that is not limited to the paraxial and sag height <span class="hlt">approximations</span>. A function is derived to model sections through the principal meridian of a lens, followed by <span class="hlt">rotation</span> of the section through orthogonal and oblique meridians. Average focal length is determined using the definition for the average of a function. Average univariate power in the principal meridian (including spherical aberration), can be computed from the average of a function over the angle of incidence as determined by the parameters of the given lens, or adequately computed from an integrated series function. Average power through orthogonal and oblique meridians, can be similarly determined using the derived formulae. The widely used computation for measuring refractive error, the spherical equivalent, introduces non-constant <span class="hlt">approximations</span>, leading to a systematic bias. The equations proposed provide a good univariate representation of average lens power and are not subject to a systematic bias. They are particularly useful for the analysis of aggregate data, correlating with biological treatment variables and for developing analyses, which require a scalar equivalent representation of refractive power.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22757548','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22757548"><span>Kinetic Monte Carlo simulations of travelling pulses and spiral <span class="hlt">waves</span> in the lattice Lotka-Volterra model.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Makeev, Alexei G; Kurkina, Elena S; Kevrekidis, Ioannis G</p> <p>2012-06-01</p> <p>Kinetic Monte Carlo simulations are used to study the stochastic two-species Lotka-Volterra model on a square lattice. For certain values of the model parameters, the system constitutes an excitable medium: travelling pulses and <span class="hlt">rotating</span> spiral <span class="hlt">waves</span> can be excited. Stable solitary pulses travel with constant (modulo stochastic fluctuations) shape and speed along a periodic lattice. The spiral <span class="hlt">waves</span> observed persist sometimes for hundreds of <span class="hlt">rotations</span>, but they are ultimately unstable and break-up (because of fluctuations and interactions between neighboring fronts) giving rise to complex dynamic behavior in which numerous small spiral <span class="hlt">waves</span> <span class="hlt">rotate</span> and interact with each other. It is interesting that travelling pulses and spiral <span class="hlt">waves</span> can be exhibited by the model even for completely immobile species, due to the non-local reaction kinetics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017DPS....4940202T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017DPS....4940202T"><span>Dynamics of Tidally Locked, Ultrafast <span class="hlt">Rotating</span> Atmospheres</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tan, Xianyu; Showman, Adam P.</p> <p>2017-10-01</p> <p>Tidally locked gas giants, which exhibit a novel regime of day-night thermal forcing and extreme stellar irradiation, are typically in several-day orbits, implying slow <span class="hlt">rotation</span> and a modest role for <span class="hlt">rotation</span> in the atmospheric circulation. Nevertheless, there exist a class of gas-giant, highly irradiated objects - brown dwarfs orbiting white dwarfs in extremely tight orbits - whose orbital and hence <span class="hlt">rotation</span> periods are as short as 1-2 hours. Spitzer phase curves and other observations have already been obtained for this fascinating class of objects, which raise fundamental questions about the role of <span class="hlt">rotation</span> in controlling the circulation. So far, most modeling studies have investigated <span class="hlt">rotation</span> periods exceeding a day, as appropriate for typical hot Jupiters. In this work we investigate the dynamics of tidally locked atmospheres in shorter <span class="hlt">rotation</span> periods down to about two hours. With increasing <span class="hlt">rotation</span> rate (decreasing <span class="hlt">rotation</span> period), we show that the width of the equatorial eastward jet decreases, consistent with the narrowing of <span class="hlt">wave</span>-mean-flow interacting region due to decrease of the equatorial deformation radius. The eastward-shifted equatorial hot spot offset decreases accordingly, and the westward-shifted hot regions poleward of the equatorial jet associated with Rossby gyres become increasingly distinctive. At high latitudes, winds becomes weaker and more geostrophic. The day-night temperature contrast becomes larger due to the stronger influence of <span class="hlt">rotation</span>. Our simulated atmospheres exhibit small-scale variability, presumably caused by shear instability. Unlike typical hot Jupiters, phase curves of fast-<span class="hlt">rotating</span> models show an alignment of peak flux to secondary eclipse. Our results have important implications for phase curve observations of brown dwarfs orbiting white dwarfs in ultra tight orbits.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005ASAJ..117.1796M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005ASAJ..117.1796M"><span>A first-order statistical smoothing <span class="hlt">approximation</span> for the coherent <span class="hlt">wave</span> field in random porous random media</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Müller, Tobias M.; Gurevich, Boris</p> <p>2005-04-01</p> <p>An important dissipation mechanism for <span class="hlt">waves</span> in randomly inhomogeneous poroelastic media is the effect of <span class="hlt">wave</span>-induced fluid flow. In the framework of Biot's theory of poroelasticity, this mechanism can be understood as scattering from fast into slow compressional <span class="hlt">waves</span>. To describe this conversion scattering effect in poroelastic random media, the dynamic characteristics of the coherent wavefield using the theory of statistical <span class="hlt">wave</span> propagation are analyzed. In particular, the method of statistical smoothing is applied to Biot's equations of poroelasticity. Within the accuracy of the first-order statistical smoothing an effective <span class="hlt">wave</span> number of the coherent field, which accounts for the effect of <span class="hlt">wave</span>-induced flow, is derived. This <span class="hlt">wave</span> number is complex and involves an integral over the correlation function of the medium's fluctuations. It is shown that the known one-dimensional (1-D) result can be obtained as a special case of the present 3-D theory. The expression for the effective <span class="hlt">wave</span> number allows to derive a model for elastic attenuation and dispersion due to <span class="hlt">wave</span>-induced fluid flow. These wavefield attributes are analyzed in a companion paper. .</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S21E0355P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S21E0355P"><span>Three-Dimensional Velocity Structure in Southern California from Teleseismic Surface <span class="hlt">Waves</span> and Body <span class="hlt">Waves</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Prindle-Sheldrake, K. L.; Tanimoto, T.</p> <p>2003-12-01</p> <p>Analysis of teleseismic <span class="hlt">waves</span> generated by large earthquakes worldwide across the Southern California TriNet Seismic Broadband Array has yielded high quality measurements of both surface <span class="hlt">waves</span> and body <span class="hlt">waves</span>. Rayleigh <span class="hlt">waves</span> and Love <span class="hlt">waves</span> were previously analyzed using a spectral fitting technique (Tanimoto. and Prindle-Sheldrake, GRL 2002; Prindle-Sheldrake and Tanimoto, submitted to JGR), producing a three-dimensional S-<span class="hlt">wave</span> velocity structure. Features in our velocity structure show some regional contrasts with respect to the starting model (SCEC 2.2), which has detailed crustal structure, but laterally homogeneous upper mantle structure. The most prominent of which is a postulated fast velocity anomaly located west of the Western Transverse Ranges that could be related to a <span class="hlt">rotated</span> remnant plate from Farallon subduction. Analysis indicates that, while Rayleigh <span class="hlt">wave</span> data are mostly sensitive to mantle structure, Love <span class="hlt">wave</span> data require some modifications of crustal structure from SCEC 2.2 model. Recent advances in our velocity structure focus on accommodation of finite frequency effect, and the addition of body <span class="hlt">waves</span> to the data. Thus far, 118 events have been analyzed for body <span class="hlt">waves</span>. A simple geometrical approach is used to represent the finite frequency effect in phase velocity maps. Due to concerns that, for seismic phases between 10-100 seconds, structure away from the ray theoretical is also sampled by a propagating surface <span class="hlt">wave</span>, we have adopted a technique which examines a normal mode formula in its asymptotic limit (Tanimoto, GRL 2003 in press). An ellipse, based on both distance from source to receiver and wavelength, can be used to <span class="hlt">approximate</span> the effect on the structure along the ray path and adjacent structure. Three models were tested in order to select the appropriate distribution within the ellipse; the first case gives equal weight to all blocks within the ellipse; case 2 incorporates a Gaussian function which falls off perpendicular to the ray</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22521935-stability-rotating-magnetized-jets-solar-atmosphere-kelvinhelmholtz-instability','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22521935-stability-rotating-magnetized-jets-solar-atmosphere-kelvinhelmholtz-instability"><span>STABILITY OF <span class="hlt">ROTATING</span> MAGNETIZED JETS IN THE SOLAR ATMOSPHERE. I. KELVIN–HELMHOLTZ INSTABILITY</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zaqarashvili, Teimuraz V.; Zhelyazkov, Ivan; Ofman, Leon, E-mail: teimuraz.zaqarashvili@uni-graz.at</p> <p>2015-11-10</p> <p>Observations show various jets in the solar atmosphere with significant <span class="hlt">rotational</span> motions, which may undergo instabilities leading to heat ambient plasma. We study the Kelvin–Helmholtz instability (KHI) of twisted and <span class="hlt">rotating</span> jets caused by the velocity jumps near the jet surface. We derive a dispersion equation with appropriate boundary conditions for total pressure (including centrifugal force of tube <span class="hlt">rotation</span>), which governs the dynamics of incompressible jets. Then, we obtain analytical instability criteria of KHI in various cases, which were verified by numerical solutions to the dispersion equation. We find that twisted and <span class="hlt">rotating</span> jets are unstable to KHI when themore » kinetic energy of <span class="hlt">rotation</span> is more than the magnetic energy of the twist. Our analysis shows that the azimuthal magnetic field of 1–5 G can stabilize observed <span class="hlt">rotations</span> in spicule/macrospicules and X-ray/extreme-ultraviolet (EUV) jets. On the other hand, nontwisted jets are always unstable to KHI. In this case, the instability growth time is several seconds for spicule/macrospicules and a few minutes (or less) for EUV/X-ray jets. We also find that standing kink and torsional Alfvén <span class="hlt">waves</span> are always unstable near the antinodes, owing to the jump of azimuthal velocity at the surface, while the propagating <span class="hlt">waves</span> are generally stable. Kelvin–Helmholtz (KH) vortices may lead to enhanced turbulence development and heating of surrounding plasma; therefore, <span class="hlt">rotating</span> jets may provide energy for chromospheric and coronal heating.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5650H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5650H"><span>Experimental study of inertial <span class="hlt">waves</span> in a spherical shell induced by librations of the inner sphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hoff, Michael; Harlander, Uwe; Jahangir, Saad; Egbers, Christoph</p> <p>2015-04-01</p> <p>Many planetary bodies do not <span class="hlt">rotate</span> with a constant velocity but undergo <span class="hlt">rotations</span> with superposed oscillations called longitudinal librations. This is the case e.g. for the Earth's moon, Mars' moon, Mercury and many other moons of Jupiter and Saturn and some of them have a solid inner core and a molten outer core. It is worth to know the interaction between the libration of the core and the interior of the fluid to understand tidal heating, fluid mixing, and the generation of magnetic fields. Here we present an experimental investigation of inertial <span class="hlt">waves</span> in a spherical shell. The shell <span class="hlt">rotates</span> with a mean angular velocity Ω around its vertical axis overlaid by a time periodic oscillation of the inner sphere in the range 0 < ω < 2Ω, in order to excite inertial <span class="hlt">waves</span> with a known frequency. We want to show the influence of the libration amplitude ɛ on different libration frequencies ω and how efficient libration is, to excite inertial <span class="hlt">waves</span> in the given frequency range. For low ω and high ɛ instability starts to grow and, beside the excited inertial <span class="hlt">waves</span>, several low frequency structures can be found. Quantitative PIV analyses of the horizontal plane in the co-<span class="hlt">rotation</span> frame show clear spiral structures with different <span class="hlt">wave</span> numbers for high libration amplitudes due to strong shear, similar to differential <span class="hlt">rotation</span>. Another question, we like to address, is whether high libration amplitudes can also excite very low frequency Rossby <span class="hlt">wave</span> structures? If the frequency increases, it can be seen from Poincaré plots that large attractor windows for inertial <span class="hlt">waves</span> appear. We want to show PIV analyses for such flows dominated by <span class="hlt">wave</span> attractors. It is known that for large excitation frequencies subharmonic parametric instability starts to grow and triads will be excited. Our experimental data show hints for the existence of triads and preliminary results will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JCAP...05..030Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JCAP...05..030Z"><span>Velocity Memory Effect for polarized gravitational <span class="hlt">waves</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, P.-M.; Duval, C.; Gibbons, G. W.; Horvathy, P. A.</p> <p>2018-05-01</p> <p>Circularly polarized gravitational sandwich <span class="hlt">waves</span> exhibit, as do their linearly polarized counterparts, the Velocity Memory Effect: freely falling test particles in the flat after-zone fly apart along straight lines with constant velocity. In the inside zone their trajectories combine oscillatory and <span class="hlt">rotational</span> motions in a complicated way. For circularly polarized periodic gravitational <span class="hlt">waves</span> some trajectories remain bounded, while others spiral outward. These <span class="hlt">waves</span> admit an additional "screw" isometry beyond the usual five. The consequences of this extra symmetry are explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26328726','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26328726"><span>A phase space approach to <span class="hlt">wave</span> propagation with dispersion.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ben-Benjamin, Jonathan S; Cohen, Leon; Loughlin, Patrick J</p> <p>2015-08-01</p> <p>A phase space <span class="hlt">approximation</span> method for linear dispersive <span class="hlt">wave</span> propagation with arbitrary initial conditions is developed. The results expand on a previous <span class="hlt">approximation</span> in terms of the Wigner distribution of a single mode. In contrast to this previously considered single-mode case, the <span class="hlt">approximation</span> presented here is for the full <span class="hlt">wave</span> and is obtained by a different approach. This solution requires one to obtain (i) the initial modal functions from the given initial <span class="hlt">wave</span>, and (ii) the initial cross-Wigner distribution between different modal functions. The full <span class="hlt">wave</span> is the sum of modal functions. The <span class="hlt">approximation</span> is obtained for general linear <span class="hlt">wave</span> equations by transforming the equations to phase space, and then solving in the new domain. It is shown that each modal function of the <span class="hlt">wave</span> satisfies a Schrödinger-type equation where the equivalent "Hamiltonian" operator is the dispersion relation corresponding to the mode and where the wavenumber is replaced by the wavenumber operator. Application to the beam equation is considered to illustrate the approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021490&hterms=english+varieties&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Denglish%2Bvarieties','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021490&hterms=english+varieties&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Denglish%2Bvarieties"><span>The variety of MHD shock <span class="hlt">waves</span> interactions in the solar wind flow</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Grib, S. A.</p> <p>1995-01-01</p> <p>Different types of nonlinear shock <span class="hlt">wave</span> interactions in some regions of the solar wind flow are considered. It is shown, that the solar flare or nonflare CME fast shock <span class="hlt">wave</span> may disappear as the result of the collision with the <span class="hlt">rotational</span> discontinuity. By the way the appearance of the slow shock <span class="hlt">waves</span> as the consequence of the collision with other directional discontinuity namely tangential is indicated. Thus the nonlinear oblique and normal MHD shock <span class="hlt">waves</span> interactions with different solar wind discontinuities (tangential, <span class="hlt">rotational</span>, contact, shock and plasmoidal) both in the free flow and close to the gradient regions like the terrestrial magnetopause and the heliopause are described. The change of the plasma pressure across the solar wind fast shock <span class="hlt">waves</span> is also evaluated. The sketch of the classification of the MHD discontinuities interactions, connected with the solar wind evolution is given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ComAC...3....5P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ComAC...3....5P"><span>Riemann solvers and Alfven <span class="hlt">waves</span> in black hole magnetospheres</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Punsly, Brian; Balsara, Dinshaw; Kim, Jinho; Garain, Sudip</p> <p>2016-09-01</p> <p>In the magnetosphere of a <span class="hlt">rotating</span> black hole, an inner Alfven critical surface (IACS) must be crossed by inflowing plasma. Inside the IACS, Alfven <span class="hlt">waves</span> are inward directed toward the black hole. The majority of the proper volume of the active region of spacetime (the ergosphere) is inside of the IACS. The charge and the totally transverse momentum flux (the momentum flux transverse to both the <span class="hlt">wave</span> normal and the unperturbed magnetic field) are both determined exclusively by the Alfven polarization. Thus, it is important for numerical simulations of black hole magnetospheres to minimize the dissipation of Alfven <span class="hlt">waves</span>. Elements of the dissipated <span class="hlt">wave</span> emerge in adjacent cells regardless of the IACS, there is no mechanism to prevent Alfvenic information from crossing outward. Thus, numerical dissipation can affect how simulated magnetospheres attain the substantial Goldreich-Julian charge density associated with the <span class="hlt">rotating</span> magnetic field. In order to help minimize dissipation of Alfven <span class="hlt">waves</span> in relativistic numerical simulations we have formulated a one-dimensional Riemann solver, called HLLI, which incorporates the Alfven discontinuity and the contact discontinuity. We have also formulated a multidimensional Riemann solver, called MuSIC, that enables low dissipation propagation of Alfven <span class="hlt">waves</span> in multiple dimensions. The importance of higher order schemes in lowering the numerical dissipation of Alfven <span class="hlt">waves</span> is also catalogued.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970017394','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970017394"><span>On the Asymptotic Regimes and the Strongly Stratified Limit of <span class="hlt">Rotating</span> Boussinesq Equations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Babin, A.; Mahalov, A.; Nicolaenko, B.; Zhou, Y.</p> <p>1997-01-01</p> <p>Asymptotic regimes of geophysical dynamics are described for different Burger number limits. <span class="hlt">Rotating</span> Boussinesq equations are analyzed in the asymptotic limit, of strong stratification in the Burger number of order one situation as well as in the asymptotic regime of strong stratification and weak <span class="hlt">rotation</span>. It is shown that in both regimes horizontally averaged buoyancy variable is an adiabatic invariant for the full Boussinesq system. Spectral phase shift corrections to the buoyancy time scale associated with vertical shearing of this invariant are deduced. Statistical dephasing effects induced by turbulent processes on inertial-gravity <span class="hlt">waves</span> are evidenced. The 'split' of the energy transfer of the vortical and the <span class="hlt">wave</span> components is established in the Craya-Herring cyclic basis. As the Burger number increases from zero to infinity, we demonstrate gradual unfreezing of energy cascades for ageostrophic dynamics. The energy spectrum and the anisotropic spectral eddy viscosity are deduced with an explicit dependence on the anisotropic <span class="hlt">rotation</span>/stratification time scale which depends on the vertical aspect ratio parameter. Intermediate asymptotic regime corresponding to strong stratification and weak <span class="hlt">rotation</span> is analyzed where the effects of weak <span class="hlt">rotation</span> are accounted for by an asymptotic expansion with full control (saturation) of vertical shearing. The regularizing effect of weak <span class="hlt">rotation</span> differs from regularizations based on vertical viscosity. Two scalar prognostic equations for ageostrophic components (divergent velocity potential and geostrophic departure ) are obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011pui7.book...53K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011pui7.book...53K"><span>Control of π-Electron <span class="hlt">Rotations</span> in Chiral Aromatic Molecules Using Intense Laser Pulses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanno, Manabu; Kono, Hirohiko; Fujimura, Yuichi</p> <p></p> <p>Our recent theoretical studies on laser-induced π-electron <span class="hlt">rotations</span> in chiral aromatic molecules are reviewed. π electrons of a chiral aromatic molecule can be <span class="hlt">rotated</span> along its aromatic ring by a nonhelical, linearly polarized laser pulse. An ansa aromatic molecule with a six-membered ring, 2,5-dichloro[n](3,6) pyrazinophane, which belongs to a planar-chiral molecule group, and its simplified molecule 2,5-dichloropyrazine are taken as model molecules. Electron wavepacket simulations in the frozen-molecular-vibration <span class="hlt">approximation</span> show that the initial direction of π-electron <span class="hlt">rotation</span> depends on the polarization direction of a linearly polarized laser pulse applied. Consecutive unidirectional <span class="hlt">rotation</span> can be achieved by applying a sequence of linearly polarized pump and dump pulses to prevent reverse <span class="hlt">rotation</span>. Optimal control simulations of π-electron <span class="hlt">rotation</span> show that another controlling factor for unidirectional <span class="hlt">rotation</span> is the relative optical phase between the different frequency components of an incident pulse in addition to photon polarization direction. Effects of nonadiabatic coupling between π-electron <span class="hlt">rotation</span> and molecular vibrations are also presented, where the constraints of the frozen <span class="hlt">approximation</span> are removed. The angular momentum gradually decays mainly owing to nonadiabatic coupling, while the vibrational amplitudes greatly depend on their <span class="hlt">rotation</span> direction. This suggests that the direction of π-electron <span class="hlt">rotation</span> on an attosecond timescale can be identified by detecting femtosecond molecular vibrations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060013114&hterms=time+travel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtime%2Btravel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060013114&hterms=time+travel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtime%2Btravel"><span>Direct Measurement of <span class="hlt">Wave</span> Kernels in Time-Distance Helioseismology</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Duvall, T. L., Jr.</p> <p>2006-01-01</p> <p>Solar f-mode <span class="hlt">waves</span> are surface-gravity <span class="hlt">waves</span> which propagate horizontally in a thin layer near the photosphere with a dispersion relation <span class="hlt">approximately</span> that of deep water <span class="hlt">waves</span>. At the power maximum near 3 mHz, the wavelength of 5 Mm is large enough for various <span class="hlt">wave</span> scattering properties to be observable. Gizon and Birch (2002,ApJ,571,966)h ave calculated kernels, in the Born <span class="hlt">approximation</span>, for the sensitivity of <span class="hlt">wave</span> travel times to local changes in damping rate and source strength. In this work, using isolated small magnetic features as <span class="hlt">approximate</span> point-sourc'e scatterers, such a kernel has been measured. The observed kernel contains similar features to a theoretical damping kernel but not for a source kernel. A full understanding of the effect of small magnetic features on the <span class="hlt">waves</span> will require more detailed modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1712880R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1712880R"><span>Inertia gravity <span class="hlt">waves</span> in a <span class="hlt">rotating</span>, differentially heated annulus with an upper free surface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Randriamampianina, Anthony; Harlander, Uwe; Vincze, Miklos; von Larcher, Thomas; Viazzo, Stephane</p> <p>2015-04-01</p> <p>Inertia gravity <span class="hlt">waves</span> (IGWs) are ubiquitous in the atmosphere and oceans, and are known to play a fundamental role in a wide variety of processes, among others the induction and modulation of turbulence. Observations and simulations have revealed their spontaneous occurrence simultaneously with the onset of baroclinic instability, recognized to be one of the dominant energetic processes in the large-scale atmospheric and oceanic circulations. In spite of intensive research activities these last decades, the generation mechanism and the propagation of IGWs, as well as their interaction with large-scale structures triggering locally chaotic motions, remain poorly understood. A better understanding of these phenomena is therefore mandatory for the development of IGW's parameterization schemes actually required for numerical global weather prediction. A combined laboratory experiment and direct numerical simulations study is proposed for the detailed investigations of instabilities arising within a differentially heated <span class="hlt">rotating</span> annulus, the baroclinic cavity. The configuration corresponds to an experimental setup used at BTU, Cottbus Senftenberg, Germany [1], characterized by an open upper surface and filled with water (Pr = 7). Infrared thermography and simultaneous kalliroscope visualization in horizontal planes, illuminated by a laser sheet, have been applied to detect the surface signatures of IGWs. These findings confirmed the computations carried out by three different numerical approaches, using either spectral methods, high order compact finite difference scheme (M2P2, Marseille), or the EULAG code (Freie Universitaet Berlin). These small-scale features have been observed in addition to those developing along the inner cold cylinder, previously identified by simulations in a closed cavity, filled with a liquid defined by Pr = 16 [2]. These new IGWs show characteristics similar to the ones obtained by [3] at the exit of the meandering jet between the cyclonic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018LMaPh.108..185B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018LMaPh.108..185B"><span>On the dipole <span class="hlt">approximation</span> with error estimates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boßmann, Lea; Grummt, Robert; Kolb, Martin</p> <p>2018-01-01</p> <p>The dipole <span class="hlt">approximation</span> is employed to describe interactions between atoms and radiation. It essentially consists of neglecting the spatial variation of the external field over the atom. Heuristically, this is justified by arguing that the wavelength is considerably larger than the atomic length scale, which holds under usual experimental conditions. We prove the dipole <span class="hlt">approximation</span> in the limit of infinite wavelengths compared to the atomic length scale and estimate the rate of convergence. Our results include N-body Coulomb potentials and experimentally relevant electromagnetic fields such as plane <span class="hlt">waves</span> and laser pulses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017isms.confEWE09H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017isms.confEWE09H"><span>Advances in Molecular <span class="hlt">Rotational</span> Spectroscopy for Applied Science</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harris, Brent; Fields, Shelby S.; Pulliam, Robin; Muckle, Matt; Neill, Justin L.</p> <p>2017-06-01</p> <p>Advances in chemical sensitivity and robust, solid-state designs for microwave/millimeter-<span class="hlt">wave</span> instrumentation compel the expansion of molecular <span class="hlt">rotational</span> spectroscopy as research tool into applied science. It is familiar to consider molecular <span class="hlt">rotational</span> spectroscopy for air analysis. Those techniques for molecular <span class="hlt">rotational</span> spectroscopy are included in our presentation of a more broad application space for materials analysis using Fourier Transform Molecular <span class="hlt">Rotational</span> Resonance (FT-MRR) spectrometers. There are potentially transformative advantages for direct gas analysis of complex mixtures, determination of unknown evolved gases with parts per trillion detection limits in solid materials, and unambiguous chiral determination. The introduction of FT-MRR as an alternative detection principle for analytical chemistry has created a ripe research space for the development of new analytical methods and sampling equipment to fully enable FT-MRR. We present the current state of purpose-built FT-MRR instrumentation and the latest application measurements that make use of new sampling methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Icar..282....1N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Icar..282....1N"><span>The circulation pattern and day-night heat transport in the atmosphere of a synchronously <span class="hlt">rotating</span> aquaplanet: Dependence on planetary <span class="hlt">rotation</span> rate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Noda, S.; Ishiwatari, M.; Nakajima, K.; Takahashi, Y. O.; Takehiro, S.; Onishi, M.; Hashimoto, G. L.; Kuramoto, K.; Hayashi, Y.-Y.</p> <p>2017-01-01</p> <p>In order to investigate a possible variety of atmospheric states realized on a synchronously <span class="hlt">rotating</span> aquaplanet, an experiment studying the impact of planetary <span class="hlt">rotation</span> rate is performed using an atmospheric general circulation model (GCM) with simplified hydrological and radiative processes. The entire planetary surface is covered with a swamp ocean. The value of planetary <span class="hlt">rotation</span> rate is varied from zero to the Earth's, while other parameters such as planetary radius, mean molecular weight and total mass of atmospheric dry components, and solar constant are set to the present Earth's values. The integration results show that the atmosphere reaches statistically equilibrium states for all runs; none of the calculated cases exemplifies the runaway greenhouse state. The circulation patterns obtained are classified into four types: Type-I characterized by the dominance of a day-night thermally direct circulation, Type-II characterized by a zonal <span class="hlt">wave</span> number one resonant Rossby <span class="hlt">wave</span> over a meridionally broad westerly jet on the equator, Type-III characterized by a long time scale north-south asymmetric variation, and Type-IV characterized by a pair of mid-latitude westerly jets. With the increase of planetary <span class="hlt">rotation</span> rate, the circulation evolves from Type-I to Type-II and then to Type-III gradually and smoothly, whereas the change from Type-III to Type-IV is abrupt and discontinuous. Over a finite range of planetary <span class="hlt">rotation</span> rate, both Types-III and -IV emerge as statistically steady states, constituting multiple equilibria. In spite of the substantial changes in circulation, the net energy transport from the day side to the night side remains almost insensitive to planetary <span class="hlt">rotation</span> rate, although the partition into dry static energy and latent heat energy transports changes. The reason for this notable insensitivity is that the outgoing longwave radiation over the broad area of the day side is constrained by the radiation limit of a moist atmosphere, so that the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110002993','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110002993"><span>In Situ Guided <span class="hlt">Wave</span> Structural Health Monitoring System</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhao, George; Tittmann, Bernhard R.</p> <p>2011-01-01</p> <p>Aircraft engine <span class="hlt">rotating</span> equipment operates at high temperatures and stresses. Noninvasive inspection of microcracks in those components poses a challenge for nondestructive evaluation. A low-cost, low-profile, high-temperature ultrasonic guided <span class="hlt">wave</span> sensor was developed that detects cracks in situ. The transducer design provides nondestructive evaluation of structures and materials. A key feature of the sensor is that it withstands high temperatures and excites strong surface <span class="hlt">wave</span> energy to inspect surface and subsurface cracks. The sol-gel bismuth titanate-based surface acoustic <span class="hlt">wave</span> (SAW) sensor can generate efficient SAWs for crack inspection. The sensor is very thin (submillimeter) and can generate surface <span class="hlt">waves</span> up to 540 C. Finite element analysis of the SAW transducer design was performed to predict the sensor behavior, and experimental studies confirmed the results. The sensor can be implemented on structures of various shapes. With a spray-coating process, the sensor can be applied to the surface of large curvatures. It has minimal effect on airflow or <span class="hlt">rotating</span> equipment imbalance, and provides good sensitivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19480422','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19480422"><span>Conformer lifetimes of ethyl cyanoformate from exchange-averaged <span class="hlt">rotational</span> spectra.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>True, Nancy S</p> <p>2009-06-25</p> <p>Ethyl cyanoformate exists as a mixture of two conformers but displays three R-branch a-type band series in its <span class="hlt">rotational</span> spectrum. Simulations with population fractions 0.37 at 210 K and 0.70 at 297 K undergoing conformer exchange with average conformer lifetimes, <tau(iso)>, shorter than <span class="hlt">approximately</span> 40 ps at <span class="hlt">approximately</span> 210 K and shorter than <span class="hlt">approximately</span> 37 ps at 297 K reproduce the experimental spectra between 26.5 and 38 GHz, the exchanging species accounting for the third set of bands. The upper-limit <tau(iso)>'s are 1 order of magnitude longer than RRKM theory predictions and the population fractions are consistent with the total population with energy above 700 cm(-1), <span class="hlt">approximately</span> twice the conformer interconversion barrier height. Model calculations indicate that extensive K-sublevel mixing in individual molecular eigenstates can produce the large population and the narrow distribution of the <span class="hlt">rotational</span>-constant sum, B + C, consistent with the observed exchange-averaged band series.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017RaSc...52.1293C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017RaSc...52.1293C"><span>Faraday <span class="hlt">Rotation</span> of Automatic Dependent Surveillance-Broadcast (ADS-B) Signals as a Method of Ionospheric Characterization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cushley, A. C.; Kabin, K.; Noël, J.-M.</p> <p>2017-10-01</p> <p>Radio <span class="hlt">waves</span> propagating through plasma in the Earth's ambient magnetic field experience Faraday <span class="hlt">rotation</span>; the plane of the electric field of a linearly polarized <span class="hlt">wave</span> changes as a function of the distance travelled through a plasma. Linearly polarized radio <span class="hlt">waves</span> at 1090 MHz frequency are emitted by Automatic Dependent Surveillance Broadcast (ADS-B) devices that are installed on most commercial aircraft. These radio <span class="hlt">waves</span> can be detected by satellites in low Earth orbits, and the change of the polarization angle caused by propagation through the terrestrial ionosphere can be measured. In this manuscript we discuss how these measurements can be used to characterize the ionospheric conditions. In the present study, we compute the amount of Faraday <span class="hlt">rotation</span> from a prescribed total electron content value and two of the profile parameters of the NeQuick ionospheric model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120008345','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120008345"><span>The Epoch of Disk Formation: z is <span class="hlt">Approximately</span> l to Today</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kassin, Susan; Gardner, Jonathan; Weiner, Ben; Faber, Sandra</p> <p>2012-01-01</p> <p>We present data on galaxy kinematics, morphologies, and star-formation rates over 0.1 less than z less than 1.2 for <span class="hlt">approximately</span> 500 blue galaxies. These data show how systems like our own Milky-Way have come into being. At redshifts around 1, about half the age of the Universe ago, Milky-Way mass galaxies were different beasts than today. They had a significant amount of disturbed motions, disturbed morphologies, shallower potential wells, higher specific star-formation rates, and likely higher gas fractions. Since redshift <span class="hlt">approximately</span> 1, galaxies have decreased in disturbed motions, increased in <span class="hlt">rotation</span> velocity and potential well depth, become more well-ordered morphologically, and decreased in specific star-formation rate. We find interrelationships between these measurements. Galaxy kinematics are correlated with morphology and specific star-formation rate such that galaxies with the fastest <span class="hlt">rotation</span> velocities and the least amounts of disturbed motions have the most well-ordered morphologies and the lowest specific star-formation rates. The converse is true. Moreover, we find that the rate at which galaxies become more well-ordered kinematically (i.e., increased <span class="hlt">rotation</span> velocity, decreased disturbed motions) and morphologically is directly proportional to their stellar mass.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...855L..22B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...855L..22B"><span>Enhanced Stellar Activity for Slow Antisolar Differential <span class="hlt">Rotation</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brandenburg, Axel; Giampapa, Mark S.</p> <p>2018-03-01</p> <p>High-precision photometry of solar-like members of the open cluster M67 with Kepler/K2 data has recently revealed enhanced activity for stars with a large Rossby number, which is the ratio of <span class="hlt">rotation</span> period to the convective turnover time. Contrary to the well established behavior for shorter <span class="hlt">rotation</span> periods and smaller Rossby numbers, the chromospheric activity of the more slowly <span class="hlt">rotating</span> stars of M67 was found to increase with increasing Rossby number. Such behavior has never been reported before, although it was theoretically predicted to emerge as a consequence of antisolar differential <span class="hlt">rotation</span> (DR) for stars with Rossby numbers larger than that of the Sun, because in those models the absolute value of the DR was found to exceed that for solar-like DR. Using gyrochronological relations and an <span class="hlt">approximate</span> age of 4 Gyr for the members of M67, we compare with computed <span class="hlt">rotation</span> rates using just the B ‑ V color. The resulting rotation–activity relation is found to be compatible with that obtained by employing the measured <span class="hlt">rotation</span> rate. This provides additional support for the unconventional enhancement of activity at comparatively low <span class="hlt">rotation</span> rates and the possible presence of antisolar differential <span class="hlt">rotation</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. Their policies may differ from this site.</div> </div><!-- container --> <footer><a id="backToTop" href="#top"> </a><nav><a id="backToTop" href="#top"> </a><ul class="links"><a id="backToTop" href="#top"> </a><li><a id="backToTop" href="#top"></a><a href="/sitemap.html">Site Map</a></li> <li><a href="/members/index.html">Members Only</a></li> <li><a href="/website-policies.html">Website Policies</a></li> <li><a href="https://doe.responsibledisclosure.com/hc/en-us" target="_blank">Vulnerability Disclosure Program</a></li> <li><a href="/contact.html">Contact Us</a></li> </ul> <div class="small">Science.gov is maintained by the U.S. Department of Energy's <a href="https://www.osti.gov/" target="_blank">Office of Scientific and Technical Information</a>, in partnership with <a href="https://www.cendi.gov/" target="_blank">CENDI</a>.</div> </nav> </footer> <script type="text/javascript"><!-- // var lastDiv = ""; function showDiv(divName) { // hide last div if (lastDiv) { document.getElementById(lastDiv).className = "hiddenDiv"; } //if value of the box is not nothing and an object with that name exists, then change the class if (divName && document.getElementById(divName)) { document.getElementById(divName).className = "visibleDiv"; lastDiv = divName; } } //--> </script> <script> /** * Function that tracks a click on an outbound link in Google Analytics. * This function takes a valid URL string as an argument, and uses that URL string * as the event label. */ var trackOutboundLink = function(url,collectionCode) { try { h = window.open(url); setTimeout(function() { ga('send', 'event', 'topic-page-click-through', collectionCode, url); }, 1000); } catch(err){} }; </script> <!-- Google Analytics --> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-1122789-34', 'auto'); ga('send', 'pageview'); </script> <!-- End Google Analytics --> <script> showDiv('page_1') </script> </body> </html>