The Stokes-Einstein relation at moderate Schmidt number.
Balboa Usabiaga, Florencio; Xie, Xiaoyi; Delgado-Buscalioni, Rafael; Donev, Aleksandar
2013-12-07
The Stokes-Einstein relation for the self-diffusion coefficient of a spherical particle suspended in an incompressible fluid is an asymptotic result in the limit of large Schmidt number, that is, when momentum diffuses much faster than the particle. When the Schmidt number is moderate, which happens in most particle methods for hydrodynamics, deviations from the Stokes-Einstein prediction are expected. We study these corrections computationally using a recently developed minimally resolved method for coupling particles to an incompressible fluctuating fluid in both two and three dimensions. We find that for moderate Schmidt numbers the diffusion coefficient is reduced relative to the Stokes-Einstein prediction by an amount inversely proportional to the Schmidt number in both two and three dimensions. We find, however, that the Einstein formula is obeyed at all Schmidt numbers, consistent with linear response theory. The mismatch arises because thermal fluctuations affect the drag coefficient for a particle due to the nonlinear nature of the fluid-particle coupling. The numerical data are in good agreement with an approximate self-consistent theory, which can be used to estimate finite-Schmidt number corrections in a variety of methods. Our results indicate that the corrections to the Stokes-Einstein formula come primarily from the fact that the particle itself diffuses together with the momentum. Our study separates effects coming from corrections to no-slip hydrodynamics from those of finite separation of time scales, allowing for a better understanding of widely observed deviations from the Stokes-Einstein prediction in particle methods such as molecular dynamics.
NASA Technical Reports Server (NTRS)
Lin, P.; Pratt, D. T.
1987-01-01
A hybrid method has been developed for the numerical prediction of turbulent mixing in a spatially-developing, free shear layer. Most significantly, the computation incorporates the effects of large-scale structures, Schmidt number and Reynolds number on mixing, which have been overlooked in the past. In flow field prediction, large-eddy simulation was conducted by a modified 2-D vortex method with subgrid-scale modeling. The predicted mean velocities, shear layer growth rates, Reynolds stresses, and the RMS of longitudinal velocity fluctuations were found to be in good agreement with experiments, although the lateral velocity fluctuations were overpredicted. In scalar transport, the Monte Carlo method was extended to the simulation of the time-dependent pdf transport equation. For the first time, the mixing frequency in Curl's coalescence/dispersion model was estimated by using Broadwell and Breidenthal's theory of micromixing, which involves Schmidt number, Reynolds number and the local vorticity. Numerical tests were performed for a gaseous case and an aqueous case. Evidence that pure freestream fluids are entrained into the layer by large-scale motions was found in the predicted pdf. Mean concentration profiles were found to be insensitive to Schmidt number, while the unmixedness was higher for higher Schmidt number. Applications were made to mixing layers with isothermal, fast reactions. The predicted difference in product thickness of the two cases was in reasonable quantitative agreement with experimental measurements.
Schmidt-number witnesses and bound entanglement
NASA Astrophysics Data System (ADS)
Sanpera, Anna; Bruß, Dagmar; Lewenstein, Maciej
2001-05-01
The Schmidt number of a mixed state characterizes the minimum Schmidt rank of the pure states needed to construct it. We investigate the Schmidt number of an arbitrary mixed state by studying Schmidt-number witnesses that detect it. We present a canonical form of such witnesses and provide constructive methods for their optimization. Finally, we present strong evidence that all bound entangled states with positive partial transpose in C3⊗C3 have Schmidt number 2.
Bernhard Schmidt and the Schmidt Telescope for Mapping the Sky
NASA Astrophysics Data System (ADS)
Wolfschmidt, G.
Bernhard Voldemar Schmidt (1879--1935) was born in Estonia. He ran an optical workshop in Mittweida, Saxonia, between 1901 and 1927. Astronomers appreciated the quality of his telescopes. Starting in 1925, working freelance in Hamburg Observatory, he developed a short focal length optical system with a large field of view. He succeeded in inventing the ``Schmidt Telescope'' in 1930, which allows the imaging a large field of the sky without any distortions. Shortly after Schmidt's death, the director of the observatory published details on the invention and production of the Schmidt Telescope. After World War II, Schmidt telescopes have been widely used. The first large Schmidt telescope was built in 1948, the ``Big Schmidt'' (126 cm), Mount Palomar, USA. Schmidt telescopes are also important tools for cosmology. The result of the Palomar Observatory Sky Surveys (1949--1958, 1985--1999) is a data base of about 20 million galaxies and over 100 million stars, supplemented in 1971 by the ESO Schmidt for the southern sky. Also high resolution spectrometers can be fitted to the Schmidt telescope. The 80 cm Schmidt telescope of Hamburg Observatory, planned since 1936, finished 1955, is on Calar Alto, Spain, since 1975. Combined with two objective prisms, it was used for a Quasar survey project.
The Mount Wilson Optical Shop during the Second World War
NASA Astrophysics Data System (ADS)
Abrahams, P.
2004-12-01
During the Second World War, the Optical Shop of Mount Wilson Observatory, located in Pasadena, engaged in a variety of exacting and pioneering ventures in optical design and fabrication. Roof prisms for military optics were produced on a large scale, leading to the production of an instruction manual, for guidance in other workshops. Triple mirrors, or autocollimating corner cubes, were another precision part made in large numbers. Aerial photography was extensively developed. Test procedures for measuring resolution of lenses were researched. Various camera shutters and film sweep mechanisms were devised. The most significant work concerned Schmidt cameras, for possible use in night-time aerial photography. Variations included a solid Schmidt, and the Schmidt Cassegrain, which was fabricated for the first time at MWO. Key figures include Don Hendrix, Roger Hayward, Aden Meinel, and Walter Adams.
NASA Astrophysics Data System (ADS)
Miatto, F. M.; Brougham, T.; Yao, A. M.
2012-07-01
We derive an analytical form of the Schmidt modes of spontaneous parametric down-conversion (SPDC) biphotons in both Cartesian and polar coordinates. We show that these correspond to Hermite-Gauss (HG) or Laguerre-Gauss (LG) modes only for a specific value of their width, and we show how such value depends on the experimental parameters. The Schmidt modes that we explicitly derive allow one to set up an optimised projection basis that maximises the mutual information gained from a joint measurement. The possibility of doing so with LG modes makes it possible to take advantage of the properties of orbital angular momentum eigenmodes. We derive a general entropic entanglement measure using the Rényi entropy as a function of the Schmidt number, K, and then retrieve the von Neumann entropy, S. Using the relation between S and K we show that, for highly entangled states, a non-ideal measurement basis does not degrade the number of shared bits by a large extent. More specifically, given a non-ideal measurement which corresponds to the loss of a fraction of the total number of modes, we can quantify the experimental parameters needed to generate an entangled SPDC state with a sufficiently high dimensionality to retain any given fraction of shared bits.
NASA Astrophysics Data System (ADS)
Yuen, Anthony C. Y.; Yeoh, Guan H.; Timchenko, Victoria; Cheung, Sherman C. P.; Chan, Qing N.; Chen, Timothy
2017-09-01
An in-house large eddy simulation (LES) based fire field model has been developed for large-scale compartment fire simulations. The model incorporates four major components, including subgrid-scale turbulence, combustion, soot and radiation models which are fully coupled. It is designed to simulate the temporal and fluid dynamical effects of turbulent reaction flow for non-premixed diffusion flame. Parametric studies were performed based on a large-scale fire experiment carried out in a 39-m long test hall facility. Several turbulent Prandtl and Schmidt numbers ranging from 0.2 to 0.5, and Smagorinsky constants ranging from 0.18 to 0.23 were investigated. It was found that the temperature and flow field predictions were most accurate with turbulent Prandtl and Schmidt numbers of 0.3, respectively, and a Smagorinsky constant of 0.2 applied. In addition, by utilising a set of numerically verified key modelling parameters, the smoke filling process was successfully captured by the present LES model.
Scalar transport across the turbulent/non-turbulent interface in jets: Schmidt number effects
NASA Astrophysics Data System (ADS)
Silva, Tiago S.; B. da Silva, Carlos; Idmec Team
2016-11-01
The dynamics of a passive scalar field near a turbulent/non-turbulent interface (TNTI) is analysed through direct numerical simulations (DNS) of turbulent planar jets, with Reynolds numbers ranging from 142 <= Reλ <= 246 , and Schmidt numbers from 0 . 07 <= Sc <= 7 . The steepness of the scalar gradient, as observed from conditional profiles near the TNTI, increases with the Schmidt number. Conditional scalar gradient budgets show that for low and moderate Schmidt numbers a diffusive superlayer emerges at the TNTI, where the scalar gradient diffusion dominates, while the production is negligible. For low Schmidt numbers the growth of the turbulent front is commanded by the molecular diffusion, whereas the scalar gradient convection is negligible. The authors acknowledge the Laboratory for Advanced Computing at University of Coimbra for providing HPC, computing, consulting resources that have contributed to the research results reported within this paper. URL http://www.lca.uc.pt.
NASA Astrophysics Data System (ADS)
Gotoh, Toshiyuki
2012-11-01
Spectrum of passive scalar variance at very high Schmidt number up to 1000 in isotropic steady turbulence has been studied by using very high resolution DNS. Gaussian random force and scalar source which are isotropic and white in time are applied at low wavenumber band. Since the Schmidt number is very large, the system was integrated for 72 large eddy turn over time for the system to forgot the initial state. It is found that the scalar spectrum attains the asymptotic k-1 spectrum in the viscous-convective range and the constant CB is found to be 5.7 which is larger than 4.9 obtained by DNS under the uniform mean scalar gradient. Reasons for the difference are inferred as the Reynolds number effect, anisotropy, difference in the scalar injection, duration of time average, and the universality of the constant is discussed. The constant CB is also compared with the prediction by the Lagrangian statistical theory for the passive scalar. The scalar spectrum in the far diffusive range is found to be exponential, which is consistent with the Kraichnan's spectrum. However, the Kraichnan spectrum was derived under the assumption that the velocity field is white in time, therefore theoretical explanation of the agreement needs to be explored. Grant-in-Aid for Scientific Research No. 21360082, Ministry of Education, Culture, Sports, Science and Technology of Japan.
NASA Astrophysics Data System (ADS)
Liu, Joseph T. C.; Barbosa Decastilho, Cintia Juliana; Fuller, Mark E.; Sane, Aakash
2017-11-01
The present work uses a perturbation procedure to deduce the small nanoparticle volume concentration conservation equations for momentum, heat and concentration diffusion. Thermal physical variables are obtained from conventional means (mixture and field theories) for alumina-water and gold-water nanofluids. In the case of gold-water nano fluid molecular dynamics results are used to estimate such properties, including transport coefficients. The very thin diffusion layer at large Schmidt numbers is found to have a great impact on the velocity and temperature profiles owing to their dependency on transport properties. This has a profound effect on the conduction surface heat transfer rate enhancement and skin friction suppression for the case of nano fluid concentration withdrawal at the wall, while the diffusional surface heat transfer rate is negligible due to large Schmidt numbers. Possible experimental directed at this interesting phenomenon is suggested.
Hybrid Reynolds-Averaged/Large-Eddy Simulations of a Co-Axial Supersonic Free-Jet Experiment
NASA Technical Reports Server (NTRS)
Baurle, R. A.; Edwards, J. R.
2009-01-01
Reynolds-averaged and hybrid Reynolds-averaged/large-eddy simulations have been applied to a supersonic coaxial jet flow experiment. The experiment utilized either helium or argon as the inner jet nozzle fluid, and the outer jet nozzle fluid consisted of laboratory air. The inner and outer nozzles were designed and operated to produce nearly pressure-matched Mach 1.8 flow conditions at the jet exit. The purpose of the computational effort was to assess the state-of-the-art for each modeling approach, and to use the hybrid Reynolds-averaged/large-eddy simulations to gather insight into the deficiencies of the Reynolds-averaged closure models. The Reynolds-averaged simulations displayed a strong sensitivity to choice of turbulent Schmidt number. The baseline value chosen for this parameter resulted in an over-prediction of the mixing layer spreading rate for the helium case, but the opposite trend was noted when argon was used as the injectant. A larger turbulent Schmidt number greatly improved the comparison of the results with measurements for the helium simulations, but variations in the Schmidt number did not improve the argon comparisons. The hybrid simulation results showed the same trends as the baseline Reynolds-averaged predictions. The primary reason conjectured for the discrepancy between the hybrid simulation results and the measurements centered around issues related to the transition from a Reynolds-averaged state to one with resolved turbulent content. Improvements to the inflow conditions are suggested as a remedy to this dilemma. Comparisons between resolved second-order turbulence statistics and their modeled Reynolds-averaged counterparts were also performed.
Velocity Resolved---Scalar Modeled Simulations of High Schmidt Number Turbulent Transport
NASA Astrophysics Data System (ADS)
Verma, Siddhartha
The objective of this thesis is to develop a framework to conduct velocity resolved - scalar modeled (VR-SM) simulations, which will enable accurate simulations at higher Reynolds and Schmidt (Sc) numbers than are currently feasible. The framework established will serve as a first step to enable future simulation studies for practical applications. To achieve this goal, in-depth analyses of the physical, numerical, and modeling aspects related to Sc " 1 are presented, specifically when modeling in the viscous-convective subrange. Transport characteristics are scrutinized by examining scalar-velocity Fourier mode interactions in Direct Numerical Simulation (DNS) datasets and suggest that scalar modes in the viscous-convective subrange do not directly affect large-scale transport for high Sc . Further observations confirm that discretization errors inherent in numerical schemes can be sufficiently large to wipe out any meaningful contribution from subfilter models. This provides strong incentive to develop more effective numerical schemes to support high Sc simulations. To lower numerical dissipation while maintaining physically and mathematically appropriate scalar bounds during the convection step, a novel method of enforcing bounds is formulated, specifically for use with cubic Hermite polynomials. Boundedness of the scalar being transported is effected by applying derivative limiting techniques, and physically plausible single sub-cell extrema are allowed to exist to help minimize numerical dissipation. The proposed bounding algorithm results in significant performance gain in DNS of turbulent mixing layers and of homogeneous isotropic turbulence. Next, the combined physical/mathematical behavior of the subfilter scalar-flux vector is analyzed in homogeneous isotropic turbulence, by examining vector orientation in the strain-rate eigenframe. The results indicate no discernible dependence on the modeled scalar field, and lead to the identification of the tensor-diffusivity model as a good representation of the subfilter flux. Velocity resolved - scalar modeled simulations of homogeneous isotropic turbulence are conducted to confirm the behavior theorized in these a priori analyses, and suggest that the tensor-diffusivity model is ideal for use in the viscous-convective subrange. Simulations of a turbulent mixing layer are also discussed, with the partial objective of analyzing Schmidt number dependence of a variety of scalar statistics. Large-scale statistics are confirmed to be relatively independent of the Schmidt number for Sc " 1, which is explained by the dominance of subfilter dissipation over resolved molecular dissipation in the simulations. Overall, the VR-SM framework presented is quite effective in predicting large-scale transport characteristics of high Schmidt number scalars, however, it is determined that prediction of subfilter quantities would entail additional modeling intended specifically for this purpose. The VR-SM simulations presented in this thesis provide us with the opportunity to overlap with experimental studies, while at the same time creating an assortment of baseline datasets for future validation of LES models, thereby satisfying the objectives outlined for this work.
Nonideal Rayleigh–Taylor mixing
Lim, Hyunkyung; Iwerks, Justin; Glimm, James; Sharp, David H.
2010-01-01
Rayleigh–Taylor mixing is a classical hydrodynamic instability that occurs when a light fluid pushes against a heavy fluid. The two main sources of nonideal behavior in Rayleigh–Taylor (RT) mixing are regularizations (physical and numerical), which produce deviations from a pure Euler equation, scale invariant formulation, and nonideal (i.e., experimental) initial conditions. The Kolmogorov theory of turbulence predicts stirring at all length scales for the Euler fluid equations without regularization. We interpret mathematical theories of existence and nonuniqueness in this context, and we provide numerical evidence for dependence of the RT mixing rate on nonideal regularizations; in other words, indeterminacy when modeled by Euler equations. Operationally, indeterminacy shows up as nonunique solutions for RT mixing, parametrized by Schmidt and Prandtl numbers, in the large Reynolds number (Euler equation) limit. Verification and validation evidence is presented for the large eddy simulation algorithm used here. Mesh convergence depends on breaking the nonuniqueness with explicit use of the laminar Schmidt and Prandtl numbers and their turbulent counterparts, defined in terms of subgrid scale models. The dependence of the mixing rate on the Schmidt and Prandtl numbers and other physical parameters will be illustrated. We demonstrate numerically the influence of initial conditions on the mixing rate. Both the dominant short wavelength initial conditions and long wavelength perturbations are observed to play a role. By examination of two classes of experiments, we observe the absence of a single universal explanation, with long and short wavelength initial conditions, and the various physical and numerical regularizations contributing in different proportions in these two different contexts. PMID:20615983
NASA Astrophysics Data System (ADS)
Murdin, P.
2000-11-01
A type of telescope, invented by the Estonian optician Bernhard Schmidt (1879-1935), that is used to photograph large areas of the sky. Because, in its original design, it was useable only for photography, the instrument is also known as the Schmidt camera. The Schmidt uses a concave spherical mirror as its light collector and corrects for the optical defect, known as spherical aberration, that i...
Small particle transport across turbulent nonisothermal boundary layers
NASA Technical Reports Server (NTRS)
Rosner, D. E.; Fernandez De La Mora, J.
1982-01-01
The interaction between turbulent diffusion, Brownian diffusion, and particle thermophoresis in the limit of vanishing particle inertial effects is quantitatively modeled for applications in gas turbines. The model is initiated with consideration of the particle phase mass conservation equation for a two-dimensional boundary layer, including the thermophoretic flux term directed toward the cold wall. A formalism of a turbulent flow near a flat plate in a heat transfer problem is adopted, and variable property effects are neglected. Attention is given to the limit of very large Schmidt numbers and the particle concentration depletion outside of the Brownian sublayer. It is concluded that, in the parameter range of interest, thermophoresis augments the high Schmidt number mass-transfer coefficient by a factor equal to the product of the outer sink and the thermophoretic suction.
Controlling the spectrum of photons generated on a silicon nanophotonic chip
Kumar, Ranjeet; Ong, Jun Rong; Savanier, Marc; Mookherjea, Shayan
2014-01-01
Directly modulated semiconductor lasers are widely used, compact light sources in optical communications. Semiconductors can also be used to generate nonclassical light; in fact, CMOS-compatible silicon chips can be used to generate pairs of single photons at room temperature. Unlike the classical laser, the photon-pair source requires control over a two-dimensional joint spectral intensity (JSI) and it is not possible to process the photons separately, as this could destroy the entanglement. Here we design a photon-pair source, consisting of planar lightwave components fabricated using CMOS-compatible lithography in silicon, which has the capability to vary the JSI. By controlling either the optical pump wavelength, or the temperature of the chip, we demonstrate the ability to select different JSIs, with a large variation in the Schmidt number. Such control can benefit high-dimensional communications where detector-timing constraints can be relaxed by realizing a large Schmidt number in a small frequency range. PMID:25410792
Crater size estimates for large-body terrestrial impact
NASA Technical Reports Server (NTRS)
Schmidt, Robert M.; Housen, Kevin R.
1988-01-01
Calculating the effects of impacts leading to global catastrophes requires knowledge of the impact process at very large size scales. This information cannot be obtained directly but must be inferred from subscale physical simulations, numerical simulations, and scaling laws. Schmidt and Holsapple presented scaling laws based upon laboratory-scale impact experiments performed on a centrifuge (Schmidt, 1980 and Schmidt and Holsapple, 1980). These experiments were used to develop scaling laws which were among the first to include gravity dependence associated with increasing event size. At that time using the results of experiments in dry sand and in water to provide bounds on crater size, they recognized that more precise bounds on large-body impact crater formation could be obtained with additional centrifuge experiments conducted in other geological media. In that previous work, simple power-law formulae were developed to relate final crater diameter to impactor size and velocity. In addition, Schmidt (1980) and Holsapple and Schmidt (1982) recognized that the energy scaling exponent is not a universal constant but depends upon the target media. Recently, Holsapple and Schmidt (1987) includes results for non-porous materials and provides a basis for estimating crater formation kinematics and final crater size. A revised set of scaling relationships for all crater parameters of interest are presented. These include results for various target media and include the kinematics of formation. Particular attention is given to possible limits brought about by very large impactors.
Hybrid Reynolds-Averaged/Large-Eddy Simulations of a Coaxial Supersonic Free-Jet Experiment
NASA Technical Reports Server (NTRS)
Baurle, Robert A.; Edwards, Jack R.
2010-01-01
Reynolds-averaged and hybrid Reynolds-averaged/large-eddy simulations have been applied to a supersonic coaxial jet flow experiment. The experiment was designed to study compressible mixing flow phenomenon under conditions that are representative of those encountered in scramjet combustors. The experiment utilized either helium or argon as the inner jet nozzle fluid, and the outer jet nozzle fluid consisted of laboratory air. The inner and outer nozzles were designed and operated to produce nearly pressure-matched Mach 1.8 flow conditions at the jet exit. The purpose of the computational effort was to assess the state-of-the-art for each modeling approach, and to use the hybrid Reynolds-averaged/large-eddy simulations to gather insight into the deficiencies of the Reynolds-averaged closure models. The Reynolds-averaged simulations displayed a strong sensitivity to choice of turbulent Schmidt number. The initial value chosen for this parameter resulted in an over-prediction of the mixing layer spreading rate for the helium case, but the opposite trend was observed when argon was used as the injectant. A larger turbulent Schmidt number greatly improved the comparison of the results with measurements for the helium simulations, but variations in the Schmidt number did not improve the argon comparisons. The hybrid Reynolds-averaged/large-eddy simulations also over-predicted the mixing layer spreading rate for the helium case, while under-predicting the rate of mixing when argon was used as the injectant. The primary reason conjectured for the discrepancy between the hybrid simulation results and the measurements centered around issues related to the transition from a Reynolds-averaged state to one with resolved turbulent content. Improvements to the inflow conditions were suggested as a remedy to this dilemma. Second-order turbulence statistics were also compared to their modeled Reynolds-averaged counterparts to evaluate the effectiveness of common turbulence closure assumptions.
Multi-fluid Dynamics for Supersonic Jet-and-Crossflows and Liquid Plug Rupture
NASA Astrophysics Data System (ADS)
Hassan, Ezeldin A.
Multi-fluid dynamics simulations require appropriate numerical treatments based on the main flow characteristics, such as flow speed, turbulence, thermodynamic state, and time and length scales. In this thesis, two distinct problems are investigated: supersonic jet and crossflow interactions; and liquid plug propagation and rupture in an airway. Gaseous non-reactive ethylene jet and air crossflow simulation represents essential physics for fuel injection in SCRAMJET engines. The regime is highly unsteady, involving shocks, turbulent mixing, and large-scale vortical structures. An eddy-viscosity-based multi-scale turbulence model is proposed to resolve turbulent structures consistent with grid resolution and turbulence length scales. Predictions of the time-averaged fuel concentration from the multi-scale model is improved over Reynolds-averaged Navier-Stokes models originally derived from stationary flow. The response to the multi-scale model alone is, however, limited, in cases where the vortical structures are small and scattered thus requiring prohibitively expensive grids in order to resolve the flow field accurately. Statistical information related to turbulent fluctuations is utilized to estimate an effective turbulent Schmidt number, which is shown to be highly varying in space. Accordingly, an adaptive turbulent Schmidt number approach is proposed, by allowing the resolved field to adaptively influence the value of turbulent Schmidt number in the multi-scale turbulence model. The proposed model estimates a time-averaged turbulent Schmidt number adapted to the computed flowfield, instead of the constant value common to the eddy-viscosity-based Navier-Stokes models. This approach is assessed using a grid-refinement study for the normal injection case, and tested with 30 degree injection, showing improved results over the constant turbulent Schmidt model both in mean and variance of fuel concentration predictions. For the incompressible liquid plug propagation and rupture study, numerical simulations are conducted using an Eulerian-Lagrangian approach with a continuous-interface method. A reconstruction scheme is developed to allow topological changes during plug rupture by altering the connectivity information of the interface mesh. Rupture time is shown to be delayed as the initial precursor film thickness increases. During the plug rupture process, a sudden increase of mechanical stresses on the tube wall is recorded, which can cause tissue damage.
Wash-away of contaminant downstream of a backward-facing step over a range of Schmidt number
NASA Astrophysics Data System (ADS)
Min, Hannah; Fischer, Paul F.; Pearlstein, Arne J.
2017-11-01
We report computations of two-dimensional unsteady convective mass transfer in flow over a backward-facing step, in which a contaminant initially present downstream of the step is ``washed away''. Results are presented for a range of Schmidt numbers, showing how the recirculation region downstream of the step not only serves to retain contaminant near the step, but also transports contaminant upstream towards the step. The results for the highest Schmidt number considered (2650) are relevant to wash-away of low-molecular weight species in liquids, for which some implications are discussed.
Chemical Reactions in Turbulent Mixing Flows.
1986-06-15
length from Reynolds and Schmidt numbers at high Reynolds number, 2. the linear dependence of flame length on the stoichiometric mixture ratio, and, 3...processes are unsteady and the observed large scale flame length fluctuations are the best evidence of the individual cascade. A more detailed examination...Damk~hler number. When the same ideas are used in a model of fuel jets burning in air, it explains (Broadwell 1982): 1. the independence of flame
Compressible turbulent mixing: Effects of Schmidt number.
Ni, Qionglin
2015-05-01
We investigated by numerical simulations the effects of Schmidt number on passive scalar transport in forced compressible turbulence. The range of Schmidt number (Sc) was 1/25∼25. In the inertial-convective range the scalar spectrum seemed to obey the k(-5/3) power law. For Sc≫1, there appeared a k(-1) power law in the viscous-convective range, while for Sc≪1, a k(-17/3) power law was identified in the inertial-diffusive range. The scaling constant computed by the mixed third-order structure function of the velocity-scalar increment showed that it grew over Sc, and the effect of compressibility made it smaller than the 4/3 value from incompressible turbulence. At small amplitudes, the probability distribution function (PDF) of scalar fluctuations collapsed to the Gaussian distribution whereas, at large amplitudes, it decayed more quickly than Gaussian. At large scales, the PDF of scalar increment behaved similarly to that of scalar fluctuation. In contrast, at small scales it resembled the PDF of scalar gradient. Furthermore, the scalar dissipation occurring at large magnitudes was found to grow with Sc. Due to low molecular diffusivity, in the Sc≫1 flow the scalar field rolled up and got mixed sufficiently. However, in the Sc≪1 flow the scalar field lost the small-scale structures by high molecular diffusivity and retained only the large-scale, cloudlike structures. The spectral analysis found that the spectral densities of scalar advection and dissipation in both Sc≫1 and Sc≪1 flows probably followed the k(-5/3) scaling. This indicated that in compressible turbulence the processes of advection and dissipation except that of scalar-dilatation coupling might deferring to the Kolmogorov picture. It then showed that at high wave numbers, the magnitudes of spectral coherency in both Sc≫1 and Sc≪1 flows decayed faster than the theoretical prediction of k(-2/3) for incompressible flows. Finally, the comparison with incompressible results showed that the scalar in compressible turbulence with Sc=1 lacked a conspicuous bump structure in its spectrum, but was more intermittent in the dissipative range.
Numerical Schemes for Dynamically Orthogonal Equations of Stochastic Fluid and Ocean Flows
2011-11-03
stages of the simulation (see §5.1). Also, because the pdf is discrete, we calculate the mo- ments using the biased estimator CYiYj ≈ 1q ∑ r Yr,iYr,j...independent random variables. For problems that require large p (e.g. non-Gaussian) and large s (e.g. large ocean or fluid simulations ), the number of...Sc = ν̂/K̂ is the Schmidt number which is the ratio of kinematic viscosity ν̂ to molecular diffusivity K̂ for the density field, ĝ′ = ĝ (ρ̂max−ρ̂min
Two-step simulation of velocity and passive scalar mixing at high Schmidt number in turbulent jets
NASA Astrophysics Data System (ADS)
Rah, K. Jeff; Blanquart, Guillaume
2016-11-01
Simulation of passive scalar in the high Schmidt number turbulent mixing process requires higher computational cost than that of velocity fields, because the scalar is associated with smaller length scales than velocity. Thus, full simulation of both velocity and passive scalar with high Sc for a practical configuration is difficult to perform. In this work, a new approach to simulate velocity and passive scalar mixing at high Sc is suggested to reduce the computational cost. First, the velocity fields are resolved by Large Eddy Simulation (LES). Then, by extracting the velocity information from LES, the scalar inside a moving fluid blob is simulated by Direct Numerical Simulation (DNS). This two-step simulation method is applied to a turbulent jet and provides a new way to examine a scalar mixing process in a practical application with smaller computational cost. NSF, Samsung Scholarship.
(UK) Schmidt - AAO style into the 1990s
NASA Astrophysics Data System (ADS)
Savage, A.
Recommendations on the use of the AAO UK Schmidt telescope during the next three years are presented. There are four important functions which must be maintained: (1) the science from the schmidt material must continue to be of the same high quality as that on which the Schmidt's reputation has been built; (2) the service to the Australian and British communities must continue despite the new trim (slim) appearance of the Schmidt staff and budget; (3) links with ROE, its plate library and photolabs which provide some of the survey atlases must be maintained; and (4) Australian and British usage of the UK's large measuring machines APM and COSMOS should be promoted.
SNOW LINES AS PROBES OF TURBULENT DIFFUSION IN PROTOPLANETARY DISKS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Owen, James E.
2014-07-20
Sharp chemical discontinuities can occur in protoplanetary disks, particularly at ''snow lines'' where a gas-phase species freezes out to form ice grains. Such sharp discontinuities will diffuse out due to the turbulence suspected to drive angular momentum transport in accretion disks. We demonstrate that the concentration gradient—in the vicinity of the snow line—of a species present outside a snow line but destroyed inside is strongly sensitive to the level of turbulent diffusion (provided the chemical and transport timescales are decoupled) and provides a direct measurement of the radial ''Schmidt number'' (the ratio of the angular momentum transport to radial turbulentmore » diffusion). Taking as an example the tracer species N{sub 2}H{sup +}, which is expected to be destroyed inside the CO snow line (as recently observed in TW Hya) we show that ALMA observations possess significant angular resolution to constrain the Schmidt number. Since different turbulent driving mechanisms predict different Schmidt numbers, a direct measurement of the Schmidt number in accretion disks would allow inferences to be made about the nature of the turbulence.« less
NASA Astrophysics Data System (ADS)
Verma, Siddhartha; Blanquart, Guillaume; P. K. Yeung Collaboration
2011-11-01
Accurate simulation of high Schmidt number scalar transport in turbulent flows is essential to studying pollutant dispersion, weather, and several oceanic phenomena. Batchelor's theory governs scalar transport in such flows, but requires further validation at high Schmidt and high Reynolds numbers. To this end, we use a new approach with the velocity field fully resolved, but the scalar field only partially resolved. The grid used is fine enough to resolve scales up to the viscous-convective subrange where the decaying slope of the scalar spectrum becomes constant. This places the cutoff wavenumber between the Kolmogorov scale and the Batchelor scale. The subgrid scale terms, which affect transport at the supergrid scales, are modeled under the assumption that velocity fluctuations are negligible beyond this cutoff wavenumber. To ascertain the validity of this technique, we performed a-priori testing on existing DNS data. This Velocity-Resolved LES (VR-LES) technique significantly reduces the computational cost of turbulent simulations of high Schmidt number scalars, and yet provides valuable information of the scalar spectrum in the viscous-convective subrange.
Turbulence Model Effects on RANS Simulations of the HIFiRE Flight 2 Ground Test Configurations
NASA Technical Reports Server (NTRS)
Georgiadis, Nicholas J.; Mankbadi, Mina R.; Vyas, Manan A.
2014-01-01
The Wind-US Reynolds-averaged Navier-Stokes solver was applied to the Hypersonic International Flight Research Experimentation (HIFiRE) Flight 2 scramjet ground test configuration. Two test points corresponding to flight Mach numbers of 5.9 and 8.9 were examined. The emphasis was examining turbulence model effects on the prediction of flow path pressures. Three variants of the Menter k-omega turbulence model family were investigated. These include the baseline (BSL) and shear stress transport (SST) as well as a modified SST model where the shear stress limiter was altered. Variations in the turbulent Schmidt number were also considered. Choice of turbulence model had a substantial effect on prediction of the flow path pressures. The BSL model produced the highest pressures and the SST model produced the lowest pressures. As expected, the settings for the turbulent Schmidt number also had significant effects on predicted pressures. Small values for the turbulent Schmidt number enabled more rapid mass transfer, faster combustion, and in turn higher flowpath pressures. Optimal settings for turbulence model and turbulent Schmidt number were found to be rather case dependent, as has been concluded in other scramjet investigations.
A Variable Turbulent Schmidt Number Formulation for Scramjet Application
NASA Technical Reports Server (NTRS)
Xiao, X.; Edwards, J. R.; Hassan, H. A.; Cutler, A. D.
2004-01-01
In high speed engines, thorough turbulent mixing of fuel and air is required to obtain high performance and high efficiency. Thus, the ability to predict turbulent mixing is crucial in obtaining accurate numerical simulation of an engine and its performance. Current state of the art in CFD simulation is to assume both turbulent Prandtl number and Schmidt numbers to be constants. However, since the mixing of fuel and air is inversely proportional to the Schmidt number, a value of 0.45 for the Schmidt number will produce twice as much diffusion as that with a value of 0.9. Because of this, current CFD tools and models have not been able to provide the needed guidance required for the efficient design of a scramjet engine. The goal of this investigation is to develop the framework needed to calculate turbulent Prandtl and Schmidt numbers as part of the solution. This requires four additional equations: two for the temperature variance and its dissipation rate and two for the concentration variance and its dissipation rate. In the current investigation emphasis will be placed on studying mixing without reactions. For such flows, variable Prandtl number does not play a major role in determining the flow. This, however, will have to be addressed when combustion is present. The approach to be used is similar to that used to develop the k-zeta model. In this approach, relevant equations are derived from the exact Navier-Stokes equations and each individual correlation is modeled. This ensures that relevant physics is incorporated into the model equations. This task has been accomplished. The final set of equations have no wall or damping functions. Moreover, they are tensorially consistent and Galilean invariant. The derivation of the model equations is rather lengthy and thus will not be incorporated into this abstract, but will be included in the final paper. As a preliminary to formulating the proposed model, the original k-zeta model with constant turbulent Prandtl and Schmidt numbers is used to model the supersonic coaxial jet mixing experiments involving He, O2 and air.
2010-06-24
diffusivity of the scalar. (If the scalar is heat, then the Schmidt number becomes the Prandtl number.) Momentum diffuses significantly faster than the...derive the Cramér function explicitly in the simple case where the xi have a Bernoulli distribution, though the general formula for S may be derived by...an analogous procedure. 5 Large deviation CLT for the Bernoulli distribution Let xi have the PDF of a fair coin, p(xi) = 1 2δ(xi + 1) + 1 2δ(xi − 1
2006-07-01
with a large-scale meta- analysis of 19 commonly used personnel selection methods across many occupations (Schmidt & Hunter, 1998)" (p. 24). Regarding...information was used to identify knowledge, skills, attributes, and other factors that should be included in a job analysis focusing on the Army aviator...military; personality; psychomotor; cognitive; job analysis ; review SECURITY CLASSIFICATION OF 19. LIMITATION OF 20. NUMBER 21. RESPONSIBLE PERSON
Effects of roughness and permeability on solute transfer at the sediment water interface.
Han, Xu; Fang, Hongwei; He, Guojian; Reible, Danny
2018-02-01
Understanding the mechanisms of solute transfer across the sediment-water interface plays a crucial role in water quality prediction and management. In this study, different arranged particles are used to form typical rough and permeable beds. Large Eddy Simulation (LES) is used to model the solute transfer from the overlying water to sediment beds. Three rough wall turbulence regimes, i.e., smooth, transitional and rough regime, are separately considered and the effects of bed roughness on solute transfer are quantitatively analyzed. Results show that the classic laws related to Schmidt numbers can well reflect the solute transfer under the smooth regime with small roughness Reynolds numbers. Under the transitional regime, the solute transfer coefficient (K L + ) is enhanced and the effect of Schmidt number is weakened by increasing roughness Reynolds number. Under the rough regime, the solute transfer is suppressed by the transition layer (Brinkman layer) and controlled by the bed permeability. Moreover, it is found that water depth, friction velocity and bed permeability can be used to estimate the solute transfer velocity (K L ) under the completely rough regime. Copyright © 2017 Elsevier Ltd. All rights reserved.
The Politics of Modernizing Short-Range Nuclear Forces in West Germany
1989-09-01
observers on both sides of the Atlantic would undoubtedly have shared the view of former West German chancellor Helmut Schmidt , who publicly termed the FOTL...Western observers were slow to note such trends in the SPD, in large part because of the dominant role Helmut Schmidt still played in setting official... Schmidt was faced with signifi- cant opposition from the outset and managed to keep his own party in line only by threatening to resign on several occasions
Report on PDF Models for Turbulence Chemistry Interaction
2014-03-01
significantly within the flowfield (like rocket plumes or scramjet combustors). For multi-species flows turbulence can increase the apparent mass...Variable Turbulent Schmidt-Number Formulation for Scramjet Applications, AIAA Journal, 44(3), 593–599. [12] Xiao, X., Hassan, H.A., and Baurle, R.A...2006), Modeling Scramjet Flows with Variable Turbulent Prandtl and Schmidt Numbers. AIAA Paper 2006-128. [13] Xiao, X., Hassan, H.A., and Baurle, R.A
Inoue, R; Yonehara, T; Miyamoto, Y; Koashi, M; Kozuma, M
2009-09-11
Three-dimensional entanglement of orbital angular momentum states of an atomic qutrit and a single photon qutrit has been observed. Their full state was reconstructed using quantum state tomography. The fidelity to the maximally entangled state of Schmidt rank 3 exceeds the threshold 2/3. This result confirms that the density matrix cannot be decomposed into an ensemble of pure states of Schmidt rank 1 or 2. That is, the Schmidt number of the density matrix must be equal to or greater than 3.
NASA Technical Reports Server (NTRS)
Deissler, Robert G
1955-01-01
The expression for eddy diffusivity from a previous analysis was modified in order to account for the effect of kinematic viscosity on the turbulence in the region close to a wall. By using the modified expression, good agreement was obtained between predicted and experimental results for heat and mass transfer at Prandtl and Schmidt numbers between 0.5 and 3000. The effects of length-to-diameter ratio and of variable viscosity were also investigated for a wide range of Prandtl numbers.
A reduced-dimensional model for near-wall transport in cardiovascular flows
Hansen, Kirk B.
2015-01-01
Near-wall mass transport plays an important role in many cardiovascular processes, including the initiation of atherosclerosis, endothelial cell vasoregulation, and thrombogenesis. These problems are characterized by large Péclet and Schmidt numbers as well as a wide range of spatial and temporal scales, all of which impose computational difficulties. In this work, we develop an analytical relationship between the flow field and near-wall mass transport for high-Schmidt-number flows. This allows for the development of a wall-shear-stress-driven transport equation that lies on a codimension-one vessel-wall surface, significantly reducing computational cost in solving the transport problem. Separate versions of this equation are developed for the reaction-rate-limited and transport-limited cases, and numerical results in an idealized abdominal aortic aneurysm are compared to those obtained by solving the full transport equations over the entire domain. The reaction-rate-limited model matches the expected results well. The transport-limited model is accurate in the developed flow regions, but overpredicts wall flux at entry regions and reattachment points in the flow. PMID:26298313
Observational Studies of Parameters Influencing Air-sea Gas Exchange
NASA Astrophysics Data System (ADS)
Schimpf, U.; Frew, N. M.; Bock, E. J.; Hara, T.; Garbe, C. S.; Jaehne, B.
A physically-based modeling of the air-sea gas transfer that can be used to predict the gas transfer rates with sufficient accuracy as a function of micrometeorological parameters is still lacking. State of the art are still simple gas transfer rate/wind speed relationships. Previous measurements from Coastal Ocean Experiment in the Atlantic revealed positive correlations between mean square slope, near surface turbulent dis- sipation, and wind stress. It also demonstrated a strong negative correlation between mean square slope and the fluorescence of surface-enriched colored dissolved organic matter. Using heat as a proxy tracer for gases the exchange process at the air/water interface and the micro turbulence at the water surface can be investigated. The anal- ysis of infrared image sequences allow the determination of the net heat flux at the ocean surface, the temperature gradient across the air/sea interface and thus the heat transfer velocity and gas transfer velocity respectively. Laboratory studies were carried out in the new Heidelberg wind-wave facility AELOTRON. Direct measurements of the Schmidt number exponent were done in conjunction with classical mass balance methods to estimate the transfer velocity. The laboratory results allowed to validate the basic assumptions of the so called controlled flux technique by applying differ- ent tracers for the gas exchange in a large Schmidt number regime. Thus a modeling of the Schmidt number exponent is able to fill the gap between laboratory and field measurements field. Both, the results from the laboratory and the field measurements should be able to give a further understanding of the mechanisms controlling the trans- port processes across the aqueous boundary layer and to relate the forcing functions to parameters measured by remote sensing.
NASA Technical Reports Server (NTRS)
Wheeler, A. A.; Mcfadden, G. B.; Murray, B. T.; Coriell, S. R.
1991-01-01
The effect of vertical, sinusoidal, time-dependent gravitational acceleration on the onset of solutal convection during directional solidification is analyzed in the limit of large modulation frequency. When the unmodulated state is unstable, the modulation amplitude required to stabilize the system is determined by the method of averaging. When the unmodulated state is stable, resonant modes of instability occur at large modulation amplitude. These are analyzed using matched asymptotic expansions to elucidate the boundary-layer structure for both the Rayleigh-Benard and directional solidification configurations. Based on these analyses, a thorough examination of the dependence of the stability criteria on the unmodulated Rayleigh number, Schmidt number, and distribution coefficient, is carried out.
NASA Astrophysics Data System (ADS)
Lawanya, T.; Vidhya, M.; Govindarajan, A.
2018-04-01
This present paper deals with the investigation of couette flow of a viscous electrically conducting incompressible fluid three dimensionally through a porous medium in presence of transverse magnetic field. Approximate Solution of equations of motion and energy equations are derived using series solution method. Hartmann number, Schmidt number and Grashoff number (or) modified Grashoff number for mass transfer on the velocity and temperature distribution are numerically discussed and shown graphically. The Nusselt number and skin friction coefficients atthe plate are derived and their numerical values are shown graphically. It is seen that in the main flow direction the velocity profiles decreases due to either an increase in Schmidt number (Or) Hartmann number.
NASA Astrophysics Data System (ADS)
Watanabe, Tomoaki; Sakai, Yasuhiko; Nagata, Koji; Ito, Yasumasa
2016-04-01
Spatially developing planar jets with passive scalar transports are simulated for various Reynolds (Re = 2200, 7000, and 22 000) and Schmidt numbers (Sc = 1, 4, 16, 64, and 128) by the implicit large eddy simulation (ILES) using low-pass filtering as an implicit subgrid-scale model. The budgets of resolved turbulent kinetic energy k and scalar variance < {φ }\\prime 2> are explicitly evaluated from the ILES data except for the dissipation terms, which are obtained from the balance in the transport equations. The budgets of k and < {φ }\\prime 2> in the ILES agree well with the DNS and experiments for both high and low Re cases. The streamwise decay of the mean turbulent kinetic energy dissipation rate obeys the power low obtained by the scaling argument. The mechanical-to-scalar timescale ratio C ϕ is evaluated in the self-similar region. For the high Re case, C ϕ is close to the isotropic value (C ϕ = 2) near the jet centerline. However, when Re is not large, C ϕ is smaller than 2 and depends on the Schmidt number. The T/NT interface is also investigated by using the scalar isosurface. The velocity and scalar fields near the interface depend on the interface orientation for all Re. The velocity toward the interface is observed near the interface facing in the streamwise, cross-streamwise, and spanwise directions in the planar jet in the resolved velocity field.
NASA Technical Reports Server (NTRS)
Khoo, Boo-Cheong; Sonin, Ain A.
1992-01-01
An experimental correlation is derived for gas absorption at a turbulent, shear-free liquid interface. The correlation is expressed in terms of the liquid-side turbulence intensity, liquid-side macroscale, and the properties of the diffusing gas and solvent. The transfer coefficient increases linearly with rms velocity up to a point where the eddy Reynolds number reaches a critical (Schmidt number dependent) value. At higher velocities, there is a more rapid linear rise. The slope of the lower Reynolds number region is proportional to the square root of the diffusivity; at Reynolds numbers much higher than that of the break point, the slope becomes independent of diffusivity.
Whitebark pine ecosystem restoration in western Montana
Robert E. Keane; Stephen F. Arno
1996-01-01
Whitebark pine (Pinus albicaulis) is a major tree species of upper subalpine forests of the northern Rocky Mountains (Schmidt and McDonald 1990). It is an important nutritional and structural component of wildlife habitat (Arno and Hoff 1990; Schmidt and McDonald 1990). Its large, nutlike seeds are a major food source for many birds and mammals (...
Modeling Turbulent Combustion for Variable Prandtl and Schmidt Number
NASA Technical Reports Server (NTRS)
Hassan, H. A.
2004-01-01
This report consists of two abstracts submitted for possible presentation at the AIAA Aerospace Science Meeting to be held in January 2005. Since the submittal of these abstracts we are continuing refinement of the model coefficients derived for the case of a variable Turbulent Prandtl number. The test cases being investigated are a Mach 9.2 flow over a degree ramp and a Mach 8.2 3-D calculation of crossing shocks. We have developed an axisymmetric code for treating axisymmetric flows. In addition the variable Schmidt number formulation was incorporated in the code and we are in the process of determining the model constants.
NASA Astrophysics Data System (ADS)
Rehman, Khalil Ur; Malik, Aneeqa Ashfaq; Tahir, M.; Malik, M. Y.
2018-03-01
The current pagination summarized the influence of bio-convection Schmidt number, bio-convection Peclet number and micro-organisms concentration difference parameter on the density of motile gyrotactic micro-organisms when they have interaction with the thermally stratified magneto-nanofluid flow past a vertical stretching surface. It is observed that the density of motile microorganisms is the decreasing function of the bio-convection Schmidt and Peclet numbers. It is trusted that the outcomes of present analysis will serve as a helping source for the upcoming developments regarding individualities of motile gyrotactic micro-organisms subject to boundary layer flows induced by stretching surfaces.
NASA Astrophysics Data System (ADS)
Asmus, Heiner; Staszak, Tristan; Strelnikov, Boris; Lübken, Franz-Josef; Friedrich, Martin; Rapp, Markus
2017-08-01
We present results of in situ measurements of mesosphere-lower thermosphere dusty-plasma densities including electrons, positive ions and charged aerosols conducted during the WADIS-2 sounding rocket campaign. The neutral air density was also measured, allowing for robust derivation of turbulence energy dissipation rates. A unique feature of these measurements is that they were done in a true common volume and with high spatial resolution. This allows for a reliable derivation of mean sizes and a size distribution function for the charged meteor smoke particles (MSPs). The mean particle radius derived from Schmidt numbers obtained from electron density fluctuations was ˜ 0.56 nm. We assumed a lognormal size distribution of the charged meteor smoke particles and derived the distribution width of 1.66 based on in situ-measured densities of different plasma constituents. We found that layers of enhanced meteor smoke particles' density measured by the particle detector coincide with enhanced Schmidt numbers obtained from the electron and neutral density fluctuations. Thus, we found that large particles with sizes > 1 nm were stratified in layers of ˜ 1 km thickness and lying some kilometers apart from each other.
Status of Turbulence Modeling for Hypersonic Propulsion Flowpaths
NASA Technical Reports Server (NTRS)
Georgiadis, Nicholas J.; Yoder, Dennis A.; Vyas, Manan A.; Engblom, William A.
2012-01-01
This report provides an assessment of current turbulent flow calculation methods for hypersonic propulsion flowpaths, particularly the scramjet engine. Emphasis is placed on Reynolds-averaged Navier-Stokes (RANS) methods, but some discussion of newer meth- ods such as Large Eddy Simulation (LES) is also provided. The report is organized by considering technical issues throughout the scramjet-powered vehicle flowpath including laminar-to-turbulent boundary layer transition, shock wave / turbulent boundary layer interactions, scalar transport modeling (specifically the significance of turbulent Prandtl and Schmidt numbers) and compressible mixing. Unit problems are primarily used to conduct the assessment. In the combustor, results from calculations of a direct connect supersonic combustion experiment are also used to address the effects of turbulence model selection and in particular settings for the turbulent Prandtl and Schmidt numbers. It is concluded that RANS turbulence modeling shortfalls are still a major limitation to the accuracy of hypersonic propulsion simulations, whether considering individual components or an overall system. Newer methods such as LES-based techniques may be promising, but are not yet at a maturity to be used routinely by the hypersonic propulsion community. The need for fundamental experiments to provide data for turbulence model development and validation is discussed.
Status of turbulence modeling for hypersonic propulsion flowpaths
NASA Astrophysics Data System (ADS)
Georgiadis, Nicholas J.; Yoder, Dennis A.; Vyas, Manan A.; Engblom, William A.
2014-06-01
This report provides an assessment of current turbulent flow calculation methods for hypersonic propulsion flowpaths, particularly the scramjet engine. Emphasis is placed on Reynolds-averaged Navier-Stokes (RANS) methods, but some discussion of newer methods such as large eddy simulation (LES) is also provided. The report is organized by considering technical issues throughout the scramjet-powered vehicle flowpath, including laminar-to-turbulent boundary layer transition, shock wave/turbulent boundary layer interactions, scalar transport modeling (specifically the significance of turbulent Prandtl and Schmidt numbers), and compressible mixing. Unit problems are primarily used to conduct the assessment. In the combustor, results from calculations of a direct connect supersonic combustion experiment are also used to address the effects of turbulence model selection and in particular settings for the turbulent Prandtl and Schmidt numbers. It is concluded that RANS turbulence modeling shortfalls are still a major limitation to the accuracy of hypersonic propulsion simulations, whether considering individual components or an overall system. Newer methods such as LES-based techniques may be promising, but are not yet at a maturity to be used routinely by the hypersonic propulsion community. The need for fundamental experiments to provide data for turbulence model development and validation is discussed.
The multifractal nature of plume structure in high-Rayleigh-number convection
NASA Astrophysics Data System (ADS)
Puthenveettil, Baburaj A.; Ananthakrishna, G.; Arakeri, Jaywant H.
2005-03-01
The geometrically different planforms of near-wall plume structure in turbulent natural convection, visualized by driving the convection using concentration differences across a membrane, are shown to have a common multifractal spectrum of singularities for Rayleigh numbers in the range 1010-1011 at Schmidt number of 602. The scaling is seen for a length scale range of 25 and is independent of the Rayleigh number, the flux, the strength and nature of the large-scale flow, and the aspect ratio. Similar scaling is observed for the plume structures obtained in the presence of a weak flow across the membrane. This common non-trivial spatial scaling is proposed to be due to the same underlying generating process for the near-wall plume structures.
Image Analysis Using Quantum Entropy Scale Space and Diffusion Concepts
2009-11-01
images using a combination of analytic methods and prototype Matlab and Mathematica programs. We investigated concepts of generalized entropy and...Schmidt strength from quantum logic gate decomposition. This form of entropy gives a measure of the nonlocal content of an entangling logic gate...11 We recall that the Schmidt number is an indicator of entanglement , but not a measure of entanglement . For instance, let us compare
2005-08-01
Ph.D. Panos Fatouros, Ph.D. Jerry Hirsch, MSc, PharmD Rhonda Hoyle Kristin Schmidt Dorin Tudor, Ph.D. Jie Liu CONTRACTING ORGANIZATION: Virginia...McClish, Ph.D., Panos Fatouros, Ph.D., Jerry Hirsch, MSc, PharmD, 5e. TASK NUMBER Rhonda Hoyle, Kristin Schmidt, Dorin Tudor, Ph.D., Jie Liu 5f. WORK UNIT
Modeling Scramjet Flows with Variable Turbulent Prandtl and Schmidt Numbers
NASA Technical Reports Server (NTRS)
Xiao, X.; Hassan, H. A.; Baurle, R. A.
2006-01-01
A complete turbulence model, where the turbulent Prandtl and Schmidt numbers are calculated as part of the solution and where averages involving chemical source terms are modeled, is presented. The ability of avoiding the use of assumed or evolution Probability Distribution Functions (PDF's) results in a highly efficient algorithm for reacting flows. The predictions of the model are compared with two sets of experiments involving supersonic mixing and one involving supersonic combustion. The results demonstrate the need for consideration of turbulence/chemistry interactions in supersonic combustion. In general, good agreement with experiment is indicated.
A fast new cadioptric design for fiber-fed spectrographs
NASA Astrophysics Data System (ADS)
Saunders, Will
2012-09-01
The next generation of massively multiplexed multi-object spectrographs (DESpec, SUMIRE, BigBOSS, 4MOST, HECTOR) demand fast, efficient and affordable spectrographs, with higher resolutions (R = 3000-5000) than current designs. Beam-size is a (relatively) free parameter in the design, but the properties of VPH gratings are such that, for fixed resolution and wavelength coverage, the effect on beam-size on overall VPH efficiency is very small. For alltransmissive cameras, this suggests modest beam-sizes (say 80-150mm) to minimize costs; while for cadioptric (Schmidt-type) cameras, much larger beam-sizes (say 250mm+) are preferred to improve image quality and to minimize obstruction losses. Schmidt designs have benefits in terms of image quality, camera speed and scattered light performance, and recent advances such as MRF technology mean that the required aspherics are no longer a prohibitive cost or risk. The main objections to traditional Schmidt designs are the inaccessibility of the detector package, and the loss in throughput caused by it being in the beam. With expected count rates and current read-noise technology, the gain in camera speed allowed by Schmidt optics largely compensates for the additional obstruction losses. However, future advances in readout technology may erase most of this compensation. A new Schmidt/Maksutov-derived design is presented, which differs from previous designs in having the detector package outside the camera, and adjacent to the spectrograph pupil. The telescope pupil already contains a hole at its center, because of the obstruction from the telescope top-end. With a 250mm beam, it is possible to largely hide a 6cm × 6cm detector package and its dewar within this hole. This means that the design achieves a very high efficiency, competitive with transmissive designs. The optics are excellent, as least as good as classic Schmidt designs, allowing F/1.25 or even faster cameras. The principal hardware has been costed at $300K per arm, making the design affordable.
Extending the length and time scales of Gram-Schmidt Lyapunov vector computations
NASA Astrophysics Data System (ADS)
Costa, Anthony B.; Green, Jason R.
2013-08-01
Lyapunov vectors have found growing interest recently due to their ability to characterize systems out of thermodynamic equilibrium. The computation of orthogonal Gram-Schmidt vectors requires multiplication and QR decomposition of large matrices, which grow as N2 (with the particle count). This expense has limited such calculations to relatively small systems and short time scales. Here, we detail two implementations of an algorithm for computing Gram-Schmidt vectors. The first is a distributed-memory message-passing method using Scalapack. The second uses the newly-released MAGMA library for GPUs. We compare the performance of both codes for Lennard-Jones fluids from N=100 to 1300 between Intel Nahalem/Infiniband DDR and NVIDIA C2050 architectures. To our best knowledge, these are the largest systems for which the Gram-Schmidt Lyapunov vectors have been computed, and the first time their calculation has been GPU-accelerated. We conclude that Lyapunov vector calculations can be significantly extended in length and time by leveraging the power of GPU-accelerated linear algebra.
Takagaki, Naohisa; Kurose, Ryoichi; Kimura, Atsushi; Komori, Satoru
2016-11-14
The mass transfer across a sheared gas-liquid interface strongly depends on the Schmidt number. Here we investigate the relationship between mass transfer coefficient on the liquid side, k L , and Schmidt number, Sc, in the wide range of 0.7 ≤ Sc ≤ 1000. We apply a three-dimensional semi direct numerical simulation (SEMI-DNS), in which the mass transfer is solved based on an approximated deconvolution model (ADM) scheme, to wind-driven turbulence with mass transfer across a sheared wind-driven wavy gas-liquid interface. In order to capture the deforming gas-liquid interface, an arbitrary Lagrangian-Eulerian (ALE) method is employed. Our results show that similar to the case for flat gas-liquid interfaces, k L for the wind-driven wavy gas-liquid interface is generally proportional to Sc -0.5 , and can be roughly estimated by the surface divergence model. This trend is endorsed by the fact that the mass transfer across the gas-liquid interface is controlled mainly by streamwise vortices on the liquid side even for the wind-driven turbulence under the conditions of low wind velocities without wave breaking.
Takagaki, Naohisa; Kurose, Ryoichi; Kimura, Atsushi; Komori, Satoru
2016-01-01
The mass transfer across a sheared gas-liquid interface strongly depends on the Schmidt number. Here we investigate the relationship between mass transfer coefficient on the liquid side, kL, and Schmidt number, Sc, in the wide range of 0.7 ≤ Sc ≤ 1000. We apply a three-dimensional semi direct numerical simulation (SEMI-DNS), in which the mass transfer is solved based on an approximated deconvolution model (ADM) scheme, to wind-driven turbulence with mass transfer across a sheared wind-driven wavy gas-liquid interface. In order to capture the deforming gas-liquid interface, an arbitrary Lagrangian-Eulerian (ALE) method is employed. Our results show that similar to the case for flat gas-liquid interfaces, kL for the wind-driven wavy gas-liquid interface is generally proportional to Sc−0.5, and can be roughly estimated by the surface divergence model. This trend is endorsed by the fact that the mass transfer across the gas-liquid interface is controlled mainly by streamwise vortices on the liquid side even for the wind-driven turbulence under the conditions of low wind velocities without wave breaking. PMID:27841325
NASA Astrophysics Data System (ADS)
Ke, Fei; Qiu, Ling-Guang; Zhu, Junfa
2014-01-01
Separation and recycling of catalysts after catalytic reactions are critically required to reduce the cost of catalysts as well as to avoid the generation of waste in industrial applications. In this work, we present a facile fabrication and characterization of a novel type of MOF-based porous catalyst, namely, Fe3O4@MIL-100(Fe) core-shell magnetic microspheres. It has been shown that these catalysts not only exhibit high catalytic activities for the Claisen-Schmidt condensation reactions under environmentally friendly conditions, but remarkably, they can be easily separated and recycled without significant loss of catalytic efficiency after being used for many times. Therefore, compared to other reported catalysts used in the Claisen-Schmidt condensation reactions, these catalysts are green, cheap and more suitable for large scale industrial applications.Separation and recycling of catalysts after catalytic reactions are critically required to reduce the cost of catalysts as well as to avoid the generation of waste in industrial applications. In this work, we present a facile fabrication and characterization of a novel type of MOF-based porous catalyst, namely, Fe3O4@MIL-100(Fe) core-shell magnetic microspheres. It has been shown that these catalysts not only exhibit high catalytic activities for the Claisen-Schmidt condensation reactions under environmentally friendly conditions, but remarkably, they can be easily separated and recycled without significant loss of catalytic efficiency after being used for many times. Therefore, compared to other reported catalysts used in the Claisen-Schmidt condensation reactions, these catalysts are green, cheap and more suitable for large scale industrial applications. Electronic supplementary information (ESI) available: SEM and TEM images, and GC-MS spectra for chalcones. See DOI: 10.1039/c3nr05051c
NASA Astrophysics Data System (ADS)
Yeung, P. K.; Sreenivasan, K. R.
2014-01-01
In a recent direct numerical simulation (DNS) study [P. K. Yeung and K. R. Sreenivasan, "Spectrum of passive scalars of high molecular diffusivity in turbulent mixing," J. Fluid Mech. 716, R14 (2013)] with Schmidt number as low as 1/2048, we verified the essential physical content of the theory of Batchelor, Howells, and Townsend ["Small-scale variation of convected quantities like temperature in turbulent fluid. 2. The case of large conductivity," J. Fluid Mech. 5, 134 (1959)] for turbulent passive scalar fields with very strong diffusivity, decaying in the absence of any production mechanism. In particular, we confirmed the existence of the -17/3 power of the scalar spectral density in the so-called inertial-diffusive range. In the present paper, we consider the DNS of the same problem, but in the presence of a uniform mean gradient, which leads to the production of scalar fluctuations at (primarily) the large scales. For the parameters of the simulations, the presence of the mean gradient alters the physics of mixing fundamentally at low Peclet numbers. While the spectrum still follows a -17/3 power law in the inertial-diffusive range, the pre-factor is non-universal and depends on the magnitude of the mean scalar gradient. Spectral transfer is greatly reduced in comparison with those for moderately and weakly diffusive scalars, leading to several distinctive features such as the absence of dissipative anomaly and a new balance of terms in the spectral transfer equation for the scalar variance, differing from the case of zero gradient. We use the DNS results to present an alternative explanation for the observed scaling behavior, and discuss a few spectral characteristics in detail.
Direct Numerical Simulation of Passive Scalar Mixing in Shock Turbulence Interaction
NASA Astrophysics Data System (ADS)
Gao, Xiangyu; Bermejo-Moreno, Ivan; Larsson, Johan
2017-11-01
Passive scalar mixing in the canonical shock-turbulence interaction configuration is investigated through shock-capturing Direct Numerical Simulations (DNS). Scalar fields with different Schmidt numbers are transported by an initially isotropic turbulent flow field passing across a nominally planar shock wave. A solution-adaptive hybrid numerical scheme on Cartesian structured grids is used, that combines a fifth-order WENO scheme near shocks and a sixth-order central-difference scheme away from shocks. The simulations target variations in the shock Mach number, M (from 1.5 to 3), turbulent Mach number, Mt (from 0.1 to 0.4, including wrinkled- and broken-shock regimes), and scalar Schmidt numbers, Sc (from 0.5 to 2), while keeping the Taylor microscale Reynolds number constant (Reλ 40). The effects on passive scalar statistics are investigated, including the streamwise evolution of scalar variance budgets, pdfs and spectra, in comparison with their temporal evolution in decaying isotropic turbulence.
Surface colour photometry of galaxies with Schmidt telescopes.
NASA Technical Reports Server (NTRS)
Wray, J. D.
1972-01-01
A method is described which owes its practicality to the capability of Schmidt telescopes to record a number of galaxy images on a single plate and to the existence of high speed computer controlled area-scanning precision microdensitometers such as the Photometric Data Systems model 1010. The method of analysis results in quantitative color-index information which is displayed in a manner that allows any user to effectively study the morphological properties of the distribution of color-index in galaxies.
Extending the length and time scales of Gram–Schmidt Lyapunov vector computations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Costa, Anthony B., E-mail: acosta@northwestern.edu; Green, Jason R., E-mail: jason.green@umb.edu; Department of Chemistry, University of Massachusetts Boston, Boston, MA 02125
Lyapunov vectors have found growing interest recently due to their ability to characterize systems out of thermodynamic equilibrium. The computation of orthogonal Gram–Schmidt vectors requires multiplication and QR decomposition of large matrices, which grow as N{sup 2} (with the particle count). This expense has limited such calculations to relatively small systems and short time scales. Here, we detail two implementations of an algorithm for computing Gram–Schmidt vectors. The first is a distributed-memory message-passing method using Scalapack. The second uses the newly-released MAGMA library for GPUs. We compare the performance of both codes for Lennard–Jones fluids from N=100 to 1300 betweenmore » Intel Nahalem/Infiniband DDR and NVIDIA C2050 architectures. To our best knowledge, these are the largest systems for which the Gram–Schmidt Lyapunov vectors have been computed, and the first time their calculation has been GPU-accelerated. We conclude that Lyapunov vector calculations can be significantly extended in length and time by leveraging the power of GPU-accelerated linear algebra.« less
Coupled harmonic oscillators and their quantum entanglement.
Makarov, Dmitry N
2018-04-01
A system of two coupled quantum harmonic oscillators with the Hamiltonian H[over ̂]=1/2(1/m_{1}p[over ̂]_{1}^{2}+1/m_{2}p[over ̂]_{2}^{2}+Ax_{1}^{2}+Bx_{2}^{2}+Cx_{1}x_{2}) can be found in many applications of quantum and nonlinear physics, molecular chemistry, and biophysics. The stationary wave function of such a system is known, but its use for the analysis of quantum entanglement is complicated because of the complexity of computing the Schmidt modes. Moreover, there is no exact analytical solution to the nonstationary Schrodinger equation H[over ̂]Ψ=iℏ∂Ψ/∂t and Schmidt modes for such a dynamic system. In this paper we find a solution to the nonstationary Schrodinger equation; we also find in an analytical form a solution to the Schmidt mode for both stationary and dynamic problems. On the basis of the Schmidt modes, the quantum entanglement of the system under consideration is analyzed. It is shown that for certain parameters of the system, quantum entanglement can be very large.
Coupled harmonic oscillators and their quantum entanglement
NASA Astrophysics Data System (ADS)
Makarov, Dmitry N.
2018-04-01
A system of two coupled quantum harmonic oscillators with the Hamiltonian H ̂=1/2 (1/m1p̂1 2+1/m2p̂2 2+A x12+B x22+C x1x2) can be found in many applications of quantum and nonlinear physics, molecular chemistry, and biophysics. The stationary wave function of such a system is known, but its use for the analysis of quantum entanglement is complicated because of the complexity of computing the Schmidt modes. Moreover, there is no exact analytical solution to the nonstationary Schrodinger equation H ̂Ψ =i ℏ ∂/Ψ ∂ t and Schmidt modes for such a dynamic system. In this paper we find a solution to the nonstationary Schrodinger equation; we also find in an analytical form a solution to the Schmidt mode for both stationary and dynamic problems. On the basis of the Schmidt modes, the quantum entanglement of the system under consideration is analyzed. It is shown that for certain parameters of the system, quantum entanglement can be very large.
NASA Technical Reports Server (NTRS)
Chen, J. H.; Mahalingam, S.; Puri, I. K.; Vervisch, L.
1992-01-01
The interaction between a quasi-laminar flame and a turbulent flowfield is investigated through direct numerical simulations (DNS) of reacting flow in two- and three-dimensional domains. Effects due to finite-rate chemistry are studied using a single step global reaction A (fuel) + B (oxidizer) yields P (product), and by varying a global Damkoehler number, as a result of which the turbulence-chemistry interaction in the flame is found to generate a wide variety of conditions, ranging from near-equilibrium to near-extinction. Differential diffusion effects are studied by changing the Schmidt number of one reactive species to one-half. It is observed that laminar flamelet response is followed within the turbulent flowfield, except in regions where transient effects seem to dominate.
NASA Astrophysics Data System (ADS)
Lei, Hebing; Yao, Yong; Liu, Haopeng; Tian, Yiting; Yang, Yanfu; Gu, Yinglong
2018-06-01
An accurate algorithm by combing Gram-Schmidt orthonormalization and least square ellipse fitting technology is proposed, which could be used for phase extraction from two or three interferograms. The DC term of background intensity is suppressed by subtraction operation on three interferograms or by high-pass filter on two interferograms. Performing Gram-Schmidt orthonormalization on pre-processing interferograms, the phase shift error is corrected and a general ellipse form is derived. Then the background intensity error and the corrected error could be compensated by least square ellipse fitting method. Finally, the phase could be extracted rapidly. The algorithm could cope with the two or three interferograms with environmental disturbance, low fringe number or small phase shifts. The accuracy and effectiveness of the proposed algorithm are verified by both of the numerical simulations and experiments.
NASA Astrophysics Data System (ADS)
Clay, M. P.; Yeung, P. K.; Buaria, D.; Gotoh, T.
2017-11-01
Turbulent mixing at high Schmidt number is a multiscale problem which places demanding requirements on direct numerical simulations to resolve fluctuations down the to Batchelor scale. We use a dual-grid, dual-scheme and dual-communicator approach where velocity and scalar fields are computed by separate groups of parallel processes, the latter using a combined compact finite difference (CCD) scheme on finer grid with a static 3-D domain decomposition free of the communication overhead of memory transposes. A high degree of scalability is achieved for a 81923 scalar field at Schmidt number 512 in turbulence with a modest inertial range, by overlapping communication with computation whenever possible. On the Cray XE6 partition of Blue Waters, use of a dedicated thread for communication combined with OpenMP locks and nested parallelism reduces CCD timings by 34% compared to an MPI baseline. The code has been further optimized for the 27-petaflops Cray XK7 machine Titan using GPUs as accelerators with the latest OpenMP 4.5 directives, giving 2.7X speedup compared to CPU-only execution at the largest problem size. Supported by NSF Grant ACI-1036170, the NCSA Blue Waters Project with subaward via UIUC, and a DOE INCITE allocation at ORNL.
Numerical modeling of time-dependent bio-convective stagnation flow of a nanofluid in slip regime
NASA Astrophysics Data System (ADS)
Kumar, Rakesh; Sood, Shilpa; Shehzad, Sabir Ali; Sheikholeslami, Mohsen
A numerical investigation of unsteady stagnation point flow of bioconvective nanofluid due to an exponential deforming surface is made in this research. The effects of Brownian diffusion, thermophoresis, slip velocity and thermal jump are incorporated in the nanofluid model. By utilizing similarity transformations, the highly nonlinear partial differential equations governing present nano-bioconvective boundary layer phenomenon are reduced into ordinary differential system. The resultant expressions are solved for numerical solution by employing a well-known implicit finite difference approach termed as Keller-box method (KBM). The influence of involved parameters (unsteadiness, bioconvection Schmidt number, velocity slip, thermal jump, thermophoresis, Schmidt number, Brownian motion, bioconvection Peclet number) on the distributions of velocity, temperature, nanoparticle and motile microorganisms concentrations, the coefficient of local skin-friction, rate of heat transport, Sherwood number and local density motile microorganisms are exhibited through graphs and tables.
Long-term monitoring of sandbars on the Colorado River in Grand Canyon using remote sensing
Ross, Robert P.; Grams, Paul E.
2015-01-01
Closure of Glen Canyon Dam in 1963 dramatically changed discharge and sediment supply to the downstream Colorado River in Marble and Grand Canyons. Magnitudes of seasonal flow variation have been suppressed, while daily fluctuations have increased because of hydropower generation. Lake Powell, the upstream reservoir, traps all sediment, leaving the Paria and Little Colorado Rivers as the main suppliers of fine sediment to the system below Glen Canyon Dam. The reduction in sediment supply, along with changes in discharge, have resulted in finesediment deficit (Topping et al., 2000), leading to a decrease in the size and number of alluvial sandbars (Schmidt and Graf, 1990; Schmidt et al., 2004). However, the understanding of these important spatial and temporal changes in sandbars located along the banks of the river have been limited to infrequent measurements mostly made by direct visitation and topographic surveying (Hazel et al., 2010). Aerial photographs are the only data available from which it is possible to evaluate changes in alluvial deposits at a large number of sites and compare recent conditions with those that existed prior to the initiation of ground-based monitoring in the early 1990s. Previous studies have evaluated the effects of Glen Canyon Dam on sandbars by analysis of comprehensive maps of surficial geology that are based on seven sets of aerial imagery taken between 1935 and 1996 for selected reaches in the first 120 km downstream from Lees Ferry, Arizona (Figure 1). These studies showed that the area of exposed sand in eddy-deposition zones was less in the post-dam period than in the pre-dam period (Leschin and Schmidt, 1995; Schmidt et al., 1999b; Sondossi, 2001, Sondossi and Schmidt, 2001, Schmidt et al., 2004). In this study, we extend these analyses to encompass a 74-year period by including maps of sand deposits visible in aerial imagery taken in 2002, 2005, and 2009 for the same reaches that were mapped in the earlier studies. Results are analyzed for two post-dam periods, based on the implementation of the first controlled flood in March 1996. The period from 1965 to March 1996 is the pre-controlled flood period and was dominated by flows that fluctuated up to the maximum capacity of the Glen Canyon Dam powerplant. Beginning in 1991, fluctuations were constrained such that maximum daily flows were typically less than 65 percent of powerplant capacity. Thus, the pre-controlled flood period also includes five years of restricted dam operations. This period also included unplanned spills from the reservoir in 1983, 1984, and 1986. We refer to the period from April 1996 to 2009 as the controlled-flood period. This period consisted entirely of restricted dam operations and included three controlled floods conducted as sandbar-building experiments. We show that the areal extent of exposed sand was greater in the images taken in the controlled-flood period than in the pre-controlled flood period. We also show that in the controlled-flood period, the area of exposed sand is negatively correlated with the elapsed time since the most recent controlled flood.
Gravitational modulation of thermosolutal convection during directional solidification
NASA Astrophysics Data System (ADS)
Murray, B. T.; Coriell, S. R.; McFadden, G. B.; Wheeler, A. A.; Saunders, B. V.
1993-03-01
During directional solidification of a binary alloy at constant velocity, thermosolutal convection may occur due to the temperature and solute gradients associated with the solidification process. For vertical growth in an ideal furnace (lacking horizontal gradients) a quiescent state is possible. The effect of a time-periodic vertical gravitational acceleration (or equivalently vibration) on the onset of thermosolutal convection is calculated based on linear stability using Floquet theory. Numerical calculations for the onset of instability have been carried out for a semiconductor alloy with Schmidt number of 10 and Prandtl number of 0.1 with primary emphasis on large modulation frequencies in a microgravity environment for which the background gravitational acceleration is negligible. The numerical results demonstrate that there is a significant difference in stability depending on whether a heavier or lighter solute is rejected. For large modulation frequencies, the stability behavior can be described by either the method of averaging or an asymptotic resonant mode analysis.
Two-dimensional dynamics of elasto-inertial turbulence and its role in polymer drag reduction
NASA Astrophysics Data System (ADS)
Sid, S.; Terrapon, V. E.; Dubief, Y.
2018-02-01
The goal of the present study is threefold: (i) to demonstrate the two-dimensional nature of the elasto-inertial instability in elasto-inertial turbulence (EIT), (ii) to identify the role of the bidimensional instability in three-dimensional EIT flows, and (iii) to establish the role of the small elastic scales in the mechanism of self-sustained EIT. Direct numerical simulations of viscoelastic fluid flows are performed in both two- and three-dimensional straight periodic channels using the Peterlin finitely extensible nonlinear elastic model (FENE-P). The Reynolds number is set to Reτ=85 , which is subcritical for two-dimensional flows but beyond the transition for three-dimensional ones. The polymer properties selected correspond to those of typical dilute polymer solutions, and two moderate Weissenberg numbers, Wiτ=40 ,100 , are considered. The simulation results show that sustained turbulence can be observed in two-dimensional subcritical flows, confirming the existence of a bidimensional elasto-inertial instability. The same type of instability is also observed in three-dimensional simulations where both Newtonian and elasto-inertial turbulent structures coexist. Depending on the Wi number, one type of structure can dominate and drive the flow. For large Wi values, the elasto-inertial instability tends to prevail over the Newtonian turbulence. This statement is supported by (i) the absence of typical Newtonian near-wall vortices and (ii) strong similarities between two- and three-dimensional flows when considering larger Wi numbers. The role of small elastic scales is investigated by introducing global artificial diffusion (GAD) in the hyperbolic transport equation for polymers. The aim is to measure how the flow reacts when the smallest elastic scales are progressively filtered out. The study results show that the introduction of large polymer diffusion in the system strongly damps a significant part of the elastic scales that are necessary to feed turbulence, eventually leading to flow laminarization. A sufficiently high Schmidt number (weakly diffusive polymers) is necessary to allow self-sustained turbulence to settle. Although EIT can withstand a low amount of diffusion and remains in a nonlaminar chaotic state, adding a finite amount of GAD in the system can have an impact on the dynamics and lead to important quantitative changes, even for Schmidt numbers as large as 102. The use of GAD should therefore be avoided in viscoelastic flow simulations.
Sandri, Paolo; Mazzinghi, Piero; Da Deppo, Vania
2018-04-20
A wide-field, large-aperture, and lightweight Schmidt configuration has been studied for a space mission proposal named Extreme Universe Space Observatory free flyer (EUSO-FF). EUSO-FF will be devoted to the study of ultrahigh energy cosmic rays, i.e., with energy >5×10 19 eV, through the detection of UV fluorescence light emitted by air showers in the Earth's atmosphere. The proposed telescope has a field of view of about 50° and an entrance pupil diameter of 4.2 m. The mirror is deployable and segmented to fit the diameter of the launcher fairing; the corrector is a lightweight annular corona.
NASA Astrophysics Data System (ADS)
Alias Suba, Subbu; Muthucumaraswamy, R.
2018-04-01
A numerical analysis of transient radiative MHD(MagnetoHydroDynamic) natural convective flow of a viscous, incompressible, electrically conducting and rotating fluid along a semi-infinite isothermal vertical plate is carried out taking into consideration Hall current, rotation and first order chemical reaction.The coupled non-linear partial differential equations are expressed in difference form using implicit finite difference scheme. The difference equations are then reduced to a system of linear algebraic equations with a tri-diagonal structure which is solved by Thomas Algorithm. The primary and secondary velocity profiles, temperature profile, concentration profile, skin friction, Nusselt number and Sherwood Number are depicted graphically for a range of values of rotation parameter, Hall parameter,magnetic parameter, chemical reaction parameter, radiation parameter, Prandtl number and Schmidt number.It is recognized that rate of heat transfer and rate of mass transfer decrease with increase in time but they increase with increasing values of radiation parameter and Schmidt number respectively.
Structure-rheology relationship in a sheared lamellar fluid.
Jaju, S J; Kumaran, V
2016-03-01
The structure-rheology relationship in the shear alignment of a lamellar fluid is studied using a mesoscale model which provides access to the lamellar configurations and the rheology. Based on the equations and free energy functional, the complete set of dimensionless groups that characterize the system are the Reynolds number (ργL(2)/μ), the Schmidt number (μ/ρD), the Ericksen number (μγ/B), the interface sharpness parameter r, the ratio of the viscosities of the hydrophilic and hydrophobic parts μ(r), and the ratio of the system size and layer spacing (L/λ). Here, ρ and μ are the fluid density and average viscosity, γ is the applied strain rate, D is the coefficient of diffusion, B is the compression modulus, μ(r) is the maximum difference in the viscosity of the hydrophilic and hydrophobic parts divided by the average viscosity, and L is the system size in the cross-stream direction. The lattice Boltzmann method is used to solve the concentration and momentum equations for a two dimensional system of moderate size (L/λ=32) and for a low Reynolds number, and the other parameters are systematically varied to examine the qualitative features of the structure and viscosity evolution in different regimes. At low Schmidt numbers where mass diffusion is faster than momentum diffusion, there is fast local formation of randomly aligned domains with "grain boundaries," which are rotated by the shear flow to align along the extensional axis as time increases. This configuration offers a high resistance to flow, and the layers do not align in the flow direction even after 1000 strain units, resulting in a viscosity higher than that for an aligned lamellar phase. At high Schmidt numbers where momentum diffusion is fast, the shear flow disrupts layers before they are fully formed by diffusion, and alignment takes place by the breakage and reformation of layers by shear, resulting in defects (edge dislocations) embedded in a background of nearly aligned layers. At high Ericksen number where the viscous forces are large compared to the restoring forces due to layer compression and bending, shear tends to homogenize the concentration field, and the viscosity decreases significantly. At very high Ericksen number, shear even disrupts the layering of the lamellar phase. At low Ericksen number, shear results in the formation of well aligned layers with edge dislocations. However, these edge dislocations take a long time to anneal; the relatively small misalignment due to the defects results in a large increase in viscosity due to high layer stiffness and due to shear localization, because the layers between defects get pinned and move as a plug with no shear. An increase in the viscosity contrast between the hydrophilic and hydrophobic parts does not alter the structural characteristics during alignment. However, there is a significant increase in the viscosity, due to pinning of the layers between defects, which results in a plug flow between defects and a localization of the shear to a part of the domain.
NASA Astrophysics Data System (ADS)
Orr, Matthew; Hopkins, Philip F.
2018-06-01
I will present a simple model of non-equilibrium star formation and its relation to the scatter in the Kennicutt-Schmidt relation and large-scale star formation efficiencies in galaxies. I will highlight the importance of a hierarchy of timescales, between the galaxy dynamical time, local free-fall time, the delay time of stellar feedback, and temporal overlap in observables, in setting the scatter of the observed star formation rates for a given gas mass. Further, I will talk about how these timescales (and their associated duty-cycles of star formation) influence interpretations of the large-scale star formation efficiency in reasonably star-forming galaxies. Lastly, the connection with galactic centers and out-of-equilibrium feedback conditions will be mentioned.
Winning Attitude & Dedication to Physical Therapy Keep Sam Schmidt on Track
ERIC Educational Resources Information Center
Bosley, Nikki Prevenslik
2006-01-01
This article relates how Sam Schmidt returned to living a productive life after an accident left him with spinal cord injury. Schmidt was a former Indy Racing League driver who founded Sam Schmidt Motorsports after his accident in 2000. Schmidt's car hit the wall as he exited turn two during a practice session at Walt Disney World Speedway in…
Passalacqua, Thais Gaban; Dutra, Luiz Antonio; de Almeida, Letícia; Velásquez, Angela Maria Arenas; Torres, Fabio Aurelio Esteves; Yamasaki, Paulo Renato; dos Santos, Mariana Bastos; Regasini, Luis Octavio; Michels, Paul A M; Bolzani, Vanderlan da Silva; Graminha, Marcia A S
2015-08-15
Chalcones form a class of compounds that belong to the flavonoid family and are widely distributed in plants. Their simple structure and the ease of preparation make chalcones attractive scaffolds for the synthesis of a large number of derivatives enabling the evaluation of the effects of different functional groups on biological activities. In this Letter, we report the successful synthesis of a series of novel prenylated chalcones via Claisen-Schmidt condensation and the evaluation of their effect on the viability of the Trypanosomatidae parasites Leishmania amazonensis, Leishmania infantum and Trypanosoma cruzi. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Winkler, Stefan; Corbett, David
2014-05-01
The Southern Alps of New Zealand are among the few key study sites for investigating Holocene glacier chronologies in the mid-latitudinal Southern Hemisphere. Their characteristic highly dynamic geomorphological process systems prove, however, to be a considerable challenge for all attempts to date and palaeoclimatologically interpret the existing Holocene moraines record. As a multi-proxy approach combining 10Be terrestrial cosmogenic nuclide dating (TCND) with Schmidt-hammer testing, the recently developed Schmidt-hammer exposure-age dating (SHD) has already shown its potential in this study area (cf. Winkler 2005, 2009, 2013). An electronic Schmidt-hammer (named SilverSchmidt) was introduced by the manufacturer of the original mechanical Schmidt-hammer (Proceq SA) a few years ago. It offers, in particular, facilities for much easier data processing and constitutes a major improvement and potential replacement for the mechanical Schmidt-hammer. However, its different approach to the measurement of surface hardness - based on Q-(velocity) values instead of R-(rebound) values - is a potential drawback. This difference effectively means that measurements from the two instruments are not easily interconvertible and, hence, that the instruments cannot be used interchangeably without previous comparative tests of both instruments under field conditions. Both instruments used in this comparative study were N-type models with identical impact energy of 2.207 Nm for the plunger. To compare both instruments and explore interconvertibility, parallel measurements were performed on a selected number of boulders (10 boulders per site with 5 impacts each, at least 2 sites per moraine) on moraines of homogeneous lithology but different established ages covering the entire Holocene and the Late Glacial. All moraines are located east of the Main Divide of the Southern Alps at Mueller Glacier, Tasman Glacier, and in the outer Tasman River Valley. All paired samples (n = 50) were collected so that the plunger impacts of both instruments were set close together on the rock surface (to avoid any influence of modifications to the surface by consecutive impacts on the same spot). In order to test their performance at the higher and lower end of surface hardness, similar paired sample tests were also made on the full-metal test anvil. The results of paired samples for all sites/moraines reveal that Q-/R-value pairs are closely clustered for young surfaces but more scattered for the older ones with a corresponding moderate R2 for a calculated linear trend. The greater variability of the older, weathered surfaces with greater scatter and hence higher standard deviations and broader confidence intervals has been recognised in numerous previous Schmidt-hammer studies and is elated to the effects of micro-scale lithological variability, which becomes a more pronounced influence with time exposed to subaerial weathering. But most important, Q-values and R-values are closely related and Q-values are systematically higher than R-values by c. 10 - 12 units over most of the operational range of both instruments. Linear conversion equations indicate a conversion factor in the order of + 11 units is applicable when converting R-values to Q-values. These estimates agree well with data obtained on the standard test anvil. Given the apparent interconvertibility of the two instruments, the SilverSchmidt is regarded as a potential replacement for the mechanical Schmidt hammer. This enables, moreover, continuity in study areas with existing R-value data archives. However, when comparing data sets of different age, adjustments must be made for any changes to the instrumental calibration value over time. References: Winkler, S. (2005): The 'Schmidt hammer' as a relative-age dating technique: potential and limitations of its application on Holocene moraines in Mt Cook National Park, Southern Alps, New Zealand. New Zealand Journal of Geology and Geophysics 48, 105 - 116. Winkler, S. (2009): First attempt to combine terrestrial cosmogenic nuclide (10Be) and Schmidt hammer relative-age dating: Strauchon Glacier, Southern Alps, New Zealand. Central European Journal of Geosciences 1, 274 - 290. Winkler, S. (2013): Investigation of late-Holocene moraines in the western Southern Alps, New Zealand, applying Schmidt-hammer exposure-age dating (SHD). The Holocene (online), doi: 10.1177/0959683613512169.
Local structure of scalar flux in turbulent passive scalar mixing
NASA Astrophysics Data System (ADS)
Konduri, Aditya; Donzis, Diego
2012-11-01
Understanding the properties of scalar flux is important in the study of turbulent mixing. Classical theories suggest that it mainly depends on the large scale structures in the flow. Recent studies suggest that the mean scalar flux reaches an asymptotic value at high Peclet numbers, independent of molecular transport properties of the fluid. A large DNS database of isotropic turbulence with passive scalars forced with a mean scalar gradient with resolution up to 40963, is used to explore the structure of scalar flux based on the local topology of the flow. It is found that regions of small velocity gradients, where dissipation and enstrophy are small, constitute the main contribution to scalar flux. On the other hand, regions of very small scalar gradient (and scalar dissipation) become less important to the scalar flux at high Reynolds numbers. The scaling of the scalar flux spectra is also investigated. The k - 7 / 3 scaling proposed by Lumley (1964) is observed at high Reynolds numbers, but collapse is not complete. A spectral bump similar to that in the velocity spectrum is observed close to dissipative scales. A number of features, including the height of the bump, appear to reach an asymptotic value at high Schmidt number.
Projective filtering of the fundamental eigenmode from spatially multimode radiation
NASA Astrophysics Data System (ADS)
Pérez, A. M.; Sharapova, P. R.; Straupe, S. S.; Miatto, F. M.; Tikhonova, O. V.; Leuchs, G.; Chekhova, M. V.
2015-11-01
Lossless filtering of a single coherent (Schmidt) mode from spatially multimode radiation is a problem crucial for optics in general and for quantum optics in particular. It becomes especially important in the case of nonclassical light that is fragile to optical losses. An example is bright squeezed vacuum generated via high-gain parametric down conversion or four-wave mixing. Its highly multiphoton and multimode structure offers a huge increase in the information capacity provided that each mode can be addressed separately. However, the nonclassical signature of bright squeezed vacuum, photon-number correlations, are highly susceptible to losses. Here we demonstrate lossless filtering of a single spatial Schmidt mode by projecting the spatial spectrum of bright squeezed vacuum on the eigenmode of a single-mode fiber. Moreover, we show that the first Schmidt mode can be captured by simply maximizing the fiber-coupled intensity. Importantly, the projection operation does not affect the targeted mode and leaves it usable for further applications.
Uncompacted Myelin Lamellae and Nodal Ion Channel Disruption in POEMS Syndrome.
Hashimoto, Rina; Koike, Haruki; Takahashi, Mie; Ohyama, Ken; Kawagashira, Yuichi; Iijima, Masahiro; Sobue, Gen
2015-12-01
To elucidate the significance of uncompacted myelin lamellae (UML) and ion channel disruption at the nodes of Ranvier in the polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, we evaluated sural nerve biopsy specimens from 33 patients with POEMS syndrome and from 7 control patients. Uncompacted myelin lamellae distribution was assessed by electron microscopy and immunofluorescence microscopy. In the POEMS patient biopsies, UML were seen more frequently in small versus large myelinated fibers. Paranodes and Schmidt-Lanterman incisures, where normal physiologic UM is located, were frequently associated with UM. Widening of the nodes of Ranvier (i.e. segmental demyelination) was not associated with UML. There was axonal hollowing with neurofilament condensation at Schmidt-Lanterman incisures with abnormal UML, suggesting axonal damage at those sites in the POEMS patient biopsies. Myelin sheath irregularity was conspicuous in large myelinated fibers and was associated with abnormally widened bizarrely shaped Schmidt-Lanterman incisures. Indirect immunofluorescent studies revealed abnormalities of sodium (pan sodium) and potassium (KCNQ2) channels, even at nonwidened nodes of Ranvier. Thus, UML was not apparently associated with segmental demyelination but seemed to be associated with axonal damage. These observations suggest that nodal ion channel disruption may be associated with functional deficits in POEMS syndrome patient nerves.
Contaminant dispersal in bounded turbulent shear flow
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wallace, J.M.; Bernard, P.S.; Chiang, K.F.
The dispersion of smoke downstream of a line source at the wall and at y{sup +} = 30 in a turbulent boundary layer has been predicted with a non-local model of the scalar fluxes {bar u}c and {bar v}c. The predicted plume from the wall source has been compared to high Schmidt number experimental measurements using a combination of hot-wire anemometry to obtain velocity component data synchronously with concentration data obtained optically. The predicted plumes from the source at y{sup +} = 30 and at the wall also have been compared to a low Schmidt number direct numerical simulation. Nearmore » the source, the non-local flux models give considerably better predictions than models which account solely for mean gradient transport. At a sufficient distance downstream the gradient models gives reasonably good predictions.« less
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.
VizieR Online Data Catalog: Ultraviolet Excess Galaxies (Mitchell+ 1982)
NASA Astrophysics Data System (ADS)
Mitchell, K. J.; Brotzman, L. E.; Warnock, A.; Usher, P. D.
2015-05-01
The catalog contains a list of 412 faint galaxies selected for their apparent ultraviolet excess. The galaxies were selected from a 3-color (UBV) plate taken with the Palomar 48-inch Schmidt telescope. The 14-inch-square plates cover an area of 30 square degrees centered on Kapteyn Selected Area 28. The catalog includes running numbers, coordinates, color codes, magnitude codes, morphologies, diameters, and notes. The catalogued galaxies were selected by eye from the Palomar Schmidt 3-color (UBV) plate PS24771, centered on Kapteyn Selexted Area 28 and taken by Usher under conditions of good seeing and transparency. (1 data file).
WHAT? A Large Reflective Schmidt Telescope for the Antarctic Plateau
NASA Astrophysics Data System (ADS)
Saunders, W.; McGrath, A. J.
We present a design concept for WHAT the Wide-field Antarctic Horizontal Telescope to take advantage of the unique possibilities of Antarctica for both optical and near infrared astronomy. The design is an 8 metre, wide-field, fixed-axis, all-reflective, f/4 Schmidt telescope. Prime and Cassegrain (or Gregorian) foci are provided, giving plate scales 150-1500 μ m/'', over fields of view 3'-3circ. Diffraction limited, NGSAO-corrected K_dark images are possible over arc-minute sized fields, over most of the sky. The sensitivity, resolution, field of view and cost all compare favourably with current or proposed space or ground-based telescopes.
Cross Currents: A Journal of Communication/Language/Cross-Cultural Skills, Volume VIII, Number 1.
ERIC Educational Resources Information Center
Ryan, Gerry, Ed.
1981-01-01
This number of a journal devoted to ideas for teachers of English as a second language (ESL) contains the following articles: (1) "Using Authentic Discourse in Teaching the Conditional" by Helen Hoyt Schmidt, (2) "Better Communication through Summarizations" by John Battaglia, (3) "A Look at Discourse Analysis" by…
Pulsatile blood flow and oxygen transport past a circular cylinder.
Zierenberg, Jennifer R; Fujioka, Hideki; Hirschl, Ronald B; Bartlett, Robert H; Grotberg, James B
2007-04-01
The fundamental study of blood flow past a circular cylinder filled with an oxygen source is investigated as a building block for an artificial lung. The Casson constitutive equation is used to describe the shear-thinning and yield stress properties of blood. The presence of hemoglobin is also considered. Far from the cylinder, a pulsatile blood flow in the x direction is prescribed, represented by a time periodic (sinusoidal) component superimposed on a steady velocity. The dimensionless parameters of interest for the characterization of the flow and transport are the steady Reynolds number (Re), Womersley parameter (alpha), pulsation amplitude (A), and the Schmidt number (Sc). The Hill equation is used to describe the saturation curve of hemoglobin with oxygen. Two different feed-gas mixtures were considered: pure O(2) and air. The flow and concentration fields were computed for Re=5, 10, and 40, 0< or =A< or =0.75, alpha=0.25, 0.4, and Schmidt number, Sc=1000. The Casson fluid properties result in reduced recirculations (when present) downstream of the cylinder as compared to a Newtonian fluid. These vortices oscillate in size and strength as A and alpha are varied. Hemoglobin enhances mass transport and is especially important for an air feed which is dominated by oxyhemoglobin dispersion near the cylinder. For a pure O(2) feed, oxygen transport in the plasma dominates near the cylinder. Maximum oxygen transport is achieved by operating near steady flow (small A) for both feed-gas mixtures. The time averaged Sherwood number, Sh, is found to be largely influenced by the steady Reynolds number, increasing as Re increases and decreasing with A. Little change is observed with varying alpha for the ranges investigated. The effect of pulsatility on Sh is greater at larger Re. Increasing Re aids transport, but yields a higher cylinder drag force and shear stresses on the cylinder surface which are potentially undesirable.
Efficient Schmidt number scaling in dissipative particle dynamics
NASA Astrophysics Data System (ADS)
Krafnick, Ryan C.; García, Angel E.
2015-12-01
Dissipative particle dynamics is a widely used mesoscale technique for the simulation of hydrodynamics (as well as immersed particles) utilizing coarse-grained molecular dynamics. While the method is capable of describing any fluid, the typical choice of the friction coefficient γ and dissipative force cutoff rc yields an unacceptably low Schmidt number Sc for the simulation of liquid water at standard temperature and pressure. There are a variety of ways to raise Sc, such as increasing γ and rc, but the relative cost of modifying each parameter (and the concomitant impact on numerical accuracy) has heretofore remained undetermined. We perform a detailed search over the parameter space, identifying the optimal strategy for the efficient and accuracy-preserving scaling of Sc, using both numerical simulations and theoretical predictions. The composite results recommend a parameter choice that leads to a speed improvement of a factor of three versus previously utilized strategies.
Dissipative particle dynamics of diffusion-NMR requires high Schmidt-numbers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azhar, Mueed; Greiner, Andreas; Korvink, Jan G., E-mail: jan.korvink@kit.edu, E-mail: david.kauzlaric@imtek.uni-freiburg.de
We present an efficient mesoscale model to simulate the diffusion measurement with nuclear magnetic resonance (NMR). On the level of mesoscopic thermal motion of fluid particles, we couple the Bloch equations with dissipative particle dynamics (DPD). Thereby we establish a physically consistent scaling relation between the diffusion constant measured for DPD-particles and the diffusion constant of a real fluid. The latter is based on a splitting into a centre-of-mass contribution represented by DPD, and an internal contribution which is not resolved in the DPD-level of description. As a consequence, simulating the centre-of-mass contribution with DPD requires high Schmidt numbers. Aftermore » a verification for fundamental pulse sequences, we apply the NMR-DPD method to NMR diffusion measurements of anisotropic fluids, and of fluids restricted by walls of microfluidic channels. For the latter, the free diffusion and the localisation regime are considered.« less
NASA Astrophysics Data System (ADS)
WANG, J.; Kim, J.
2014-12-01
In this study, sensitivity of pollutant dispersion on turbulent Schmidt number (Sct) was investigated in a street canyon using a computational fluid dynamics (CFD) model. For this, numerical simulations with systematically varied Sct were performed and the CFD model results were validated against a wind‒tunnel measurement data. The results showed that root mean square error (RMSE) was quite dependent on Sct and dispersion patterns of non‒reactive scalar pollutant with different Sct were quite different among the simulation results. The RMSE was lowest in the case of Sct = 0.35 and the apparent dispersion pattern was most similar to the wind‒tunnel data in the case of Sct = 0.35. Also, numerical simulations using spatially weighted Sct were additionally performed in order for the best reproduction of the wind‒tunnel data. Detailed method and procedure to find the best reproduction will be presented.
An evaluation of gas transfer velocity parameterizations during natural convection using DNS
NASA Astrophysics Data System (ADS)
Fredriksson, Sam T.; Arneborg, Lars; Nilsson, Hâkan; Zhang, Qi; Handler, Robert A.
2016-02-01
Direct numerical simulations (DNS) of free surface flows driven by natural convection are used to evaluate different methods of estimating air-water gas exchange at no-wind conditions. These methods estimate the transfer velocity as a function of either the horizontal flow divergence at the surface, the turbulent kinetic energy dissipation beneath the surface, the heat flux through the surface, or the wind speed above the surface. The gas transfer is modeled via a passive scalar. The Schmidt number dependence is studied for Schmidt numbers of 7, 150 and 600. The methods using divergence, dissipation and heat flux estimate the transfer velocity well for a range of varying surface heat flux values, and domain depths. The two evaluated empirical methods using wind (in the limit of no wind) give reasonable estimates of the transfer velocity, depending however on the surface heat flux and surfactant saturation. The transfer velocity is shown to be well represented by the expression, ks=A |Bν|1/4 Sc-n, where A is a constant, B is the buoyancy flux, ν is the kinematic viscosity, Sc is the Schmidt number, and the exponent n depends on the water surface characteristics. The results suggest that A=0.39 and n≈1/2 and n≈2/3 for slip and no-slip boundary conditions at the surface, respectively. It is further shown that slip and no-slip boundary conditions predict the heat transfer velocity corresponding to the limits of clean and highly surfactant contaminated surfaces, respectively. This article was corrected on 22 MAR 2016. See the end of the full text for details.
Evaluation of the Schmidt-STRATOS spreader.
DOT National Transportation Integrated Search
2005-07-01
In the fall of 2004, the Maine Department of Transportation (MAINEDOT) entered into an arrangement : with Schmidt International of St.Blasien, Germany to evaluate Schmidts STRATOS material spreader. : The MAINEDOT agreed to evaluate the equipment ...
Imposition of physical parameters in dissipative particle dynamics
NASA Astrophysics Data System (ADS)
Mai-Duy, N.; Phan-Thien, N.; Tran-Cong, T.
2017-12-01
In the mesoscale simulations by the dissipative particle dynamics (DPD), the motion of a fluid is modelled by a set of particles interacting in a pairwise manner, and it has been shown to be governed by the Navier-Stokes equation, with its physical properties, such as viscosity, Schmidt number, isothermal compressibility, relaxation and inertia time scales, in fact its whole rheology resulted from the choice of the DPD model parameters. In this work, we will explore the response of a DPD fluid with respect to its parameter space, where the model input parameters can be chosen in advance so that (i) the ratio between the relaxation and inertia time scales is fixed; (ii) the isothermal compressibility of water at room temperature is enforced; and (iii) the viscosity and Schmidt number can be specified as inputs. These impositions are possible with some extra degrees of freedom in the weighting functions for the conservative and dissipative forces. Numerical experiments show an improvement in the solution quality over conventional DPD parameters/weighting functions, particularly for the number density distribution and computed stresses.
Double-diffusive boundary layers along vertical free surfaces
NASA Astrophysics Data System (ADS)
Napolitano, L. G.; Viviani, A.; Savino, R.
1992-05-01
This paper deals with double-diffusive (or thermosolutal) combined free convection, i.e., free convection due to buoyant forces (natural convection) and surface tension gradients (Marangoni convection), which are generated by volume differences and surface gradients of temperature and solute concentration. Attention is focused on boundary layers that form along a vertical liquid-gas interface, when the appropriately defined nondimensional characteristic transport numbers are large enough, in problems of thermosolutal natural and Marangoni convection, such as buoyancy and surface tension driven flows in differentially heated open cavities and liquid bridges. Classes of similar solutions are derived for each class of convection on the basis of a rigorous order of magnitude analysis. Velocity, temperature and concentration profiles are reported in the similarity plane; flow and transport properties at the liquid-gas interface (interfacial velocity, heat and mass transfer bulk coefficients) are obtained for a wide range of Prandtl and Schmidt numbers and different values of the similarity parameter.
Entanglement transitions induced by large deviations
NASA Astrophysics Data System (ADS)
Bhosale, Udaysinh T.
2017-12-01
The probability of large deviations of the smallest Schmidt eigenvalue for random pure states of bipartite systems, denoted as A and B , is computed analytically using a Coulomb gas method. It is shown that this probability, for large N , goes as exp[-β N2Φ (ζ ) ] , where the parameter β is the Dyson index of the ensemble, ζ is the large deviation parameter, while the rate function Φ (ζ ) is calculated exactly. Corresponding equilibrium Coulomb charge density is derived for its large deviations. Effects of the large deviations of the extreme (largest and smallest) Schmidt eigenvalues on the bipartite entanglement are studied using the von Neumann entropy. Effect of these deviations is also studied on the entanglement between subsystems 1 and 2, obtained by further partitioning the subsystem A , using the properties of the density matrix's partial transpose ρ12Γ. The density of states of ρ12Γ is found to be close to the Wigner's semicircle law with these large deviations. The entanglement properties are captured very well by a simple random matrix model for the partial transpose. The model predicts the entanglement transition across a critical large deviation parameter ζ . Log negativity is used to quantify the entanglement between subsystems 1 and 2. Analytical formulas for it are derived using the simple model. Numerical simulations are in excellent agreement with the analytical results.
Entanglement transitions induced by large deviations.
Bhosale, Udaysinh T
2017-12-01
The probability of large deviations of the smallest Schmidt eigenvalue for random pure states of bipartite systems, denoted as A and B, is computed analytically using a Coulomb gas method. It is shown that this probability, for large N, goes as exp[-βN^{2}Φ(ζ)], where the parameter β is the Dyson index of the ensemble, ζ is the large deviation parameter, while the rate function Φ(ζ) is calculated exactly. Corresponding equilibrium Coulomb charge density is derived for its large deviations. Effects of the large deviations of the extreme (largest and smallest) Schmidt eigenvalues on the bipartite entanglement are studied using the von Neumann entropy. Effect of these deviations is also studied on the entanglement between subsystems 1 and 2, obtained by further partitioning the subsystem A, using the properties of the density matrix's partial transpose ρ_{12}^{Γ}. The density of states of ρ_{12}^{Γ} is found to be close to the Wigner's semicircle law with these large deviations. The entanglement properties are captured very well by a simple random matrix model for the partial transpose. The model predicts the entanglement transition across a critical large deviation parameter ζ. Log negativity is used to quantify the entanglement between subsystems 1 and 2. Analytical formulas for it are derived using the simple model. Numerical simulations are in excellent agreement with the analytical results.
Standard model CP violation and cold electroweak baryogenesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tranberg, Anders
2011-10-15
Using large-scale real-time lattice simulations, we calculate the baryon asymmetry generated at a fast, cold electroweak symmetry breaking transition. CP-violation is provided by the leading effective bosonic term resulting from integrating out the fermions in the Minimal Standard Model at zero-temperature, and performing a covariant gradient expansion [A. Hernandez, T. Konstandin, and M. G. Schmidt, Nucl. Phys. B812, 290 (2009).]. This is an extension of the work presented in [A. Tranberg, A. Hernandez, T. Konstandin, and M. G. Schmidt, Phys. Lett. B 690, 207 (2010).]. The numerical implementation is described in detail, and we address issues specifically related to usingmore » this CP-violating term in the context of Cold Electroweak Baryogenesis.« less
Spectra of turbulently advected scalars that have small Schmidt number
NASA Astrophysics Data System (ADS)
Hill, Reginald J.
2017-09-01
Exact statistical equations are derived for turbulent advection of a passive scalar having diffusivity much larger than the kinematic viscosity, i.e., small Schmidt number. The equations contain all terms needed for precise direct numerical simulation (DNS) quantification. In the appropriate limit, the equations reduce to the classical theory for which the scalar spectrum is proportional to the energy spectrum multiplied by k-4, which, in turn, results in the inertial-diffusive range power law, k-17 /3. The classical theory was derived for the case of isotropic velocity and scalar fields. The exact equations are simplified for less restrictive cases: (1) locally isotropic scalar fluctuations at dissipation scales with no restriction on symmetry of the velocity field, (2) isotropic velocity field with averaging over all wave-vector directions with no restriction on the symmetry of the scalar, motivated by that average being used for DNS, and (3) isotropic velocity field with axisymmetric scalar fluctuations, motivated by the mean-scalar-gradient-source case. The equations are applied to recently published DNSs of passive scalars for the cases of a freely decaying scalar and a mean-scalar-gradient source. New terms in the exact equations are estimated for those cases and are found to be significant; those terms cause the deviations from the classical theory found by the DNS studies. A new formula for the mean-scalar-gradient case explains the variation of the scalar spectra for the DNS of the smallest Schmidt-number cases. Expansion in Legendre polynomials reveals the effect of axisymmetry. Inertial-diffusive-range formulas for both the zero- and second-order Legendre contributions are given. Exact statistical equations reveal what must be quantified using DNS to determine what causes deviations from asymptotic relationships.
Preliminary design study. Shuttle modular scanning spectroradiometer
NASA Technical Reports Server (NTRS)
1975-01-01
Fundamental concepts on which to base a detailed design for a Shuttle Modular Scanning Spectroradiometer were developed, and a preliminary design is presented. The recommended design features modularity and flexibility. It includes a 75-cm f/1.7-telescope assembly in an all-reflective Schmidt configuration, a solid state scan system (pushbroom) with high resolution over a 15 deg field of view, and ten detector channels covering the spectral range from 0.45 to 12.5 micrometers. It uses charge transfer device techniques to accommodate a large number of detector elements for earth observation measurements. Methods for in-flight radiometric calibration, for image motion compensation, and for data processing are described. Recommendations for ground support equipment are included, and interfaces with the shuttle orbiter vehicle are illustrated.
Evolve or Die: The U.S. Army’s Darwinian Challenge
2013-05-23
5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Lieutenant Colonel Todd A. Schmidt 5d...class of SAMS students, Major General Edward Cardon , Commanding General of the 2nd Infantry Division in South Korea, stated that the expectations of...uncertainty, capable of developing and leading concepts for change. “Transitions are the most important events you will have to manage,” Cardon stated
DOT National Transportation Integrated Search
2016-03-01
Richard J. Schmidt : ORCID number 0000-0003-1672-2625 : State departments of transportation (DOTs) in the west have been under increasing pressure to permit and route overweight trucks transporting machinery and equipment for the energy sector throug...
Shock Compression Chemistry in Materials Synthesis and Processing
1984-12-21
Moore at Los Alamos Scientific Laboratory [Schmidt, Moore, and Shaner, 1983; Schmidt, Moore, Schiferl , and Shaner, 1983]. More speculative, but also...Synthesis and Processing, March 28-29, Seattle, Washington. Schmidt, S. C., D. S. Moore, D. Schiferl , and J. W. Shaner. 1983. Backward stimulated Raman
Leadership: Enhancing Team Adaptability in Dynamic Settings
2008-04-01
performance , and team member satisfaction : A meta-analysis. Journal of Applied Psychology, 88, 741-749. DeShon, R. P., Kozlowski, S. W. J., Schmidt, A...University of Pennsylvania), and Steve W. J. Kozlowski (Michigan State University) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) University...NUMBER 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) U. S. Army Research Institute for the Behavioral
Lee, Young June
2016-05-10
A new cicada genus, Galgoria gen. nov., is described with Tanna herzbergi Schmidt, 1932 (from southern China) as its type species, which is placed in the subtribe Leptopsaltriina Moulton, 1923 of the tribe Leptopsaltriini Moulton, 1923 in the subfamily Cicadinae Latreille, 1802 (Hemiptera: Cicadidae). Tanna herzbergi Schmidt, 1932 is transferred from Tanna Distant, 1905 to Galgoria gen. nov. to become Galgoria herzbergi (Schmidt, 1932) comb. nov. Tanna apicalis Chen, 1940 syn. nov. and Tanna pseudocalis Lei & Chou, 1997 syn. nov. are synonymized here with Galgoria herzbergi (Schmidt, 1932) comb. nov.
Memoized Online Variational Inference for Dirichlet Process Mixture Models
2014-06-27
breaking process [7], which places artifically large mass on the final component. It is more efficient and broadly applicable than an alternative trunction...models. In Uncertainty in Artificial Intelligence , 2008. [13] N. Le Roux, M. Schmidt, and F. Bach. A stochastic gradient method with an exponential
A little-known 3-lens Catadioptric Camera by Bernard Schmidt
NASA Astrophysics Data System (ADS)
Busch, Wolfgang; Ceragioli, Roger C.; Stephani, Walter
2013-07-01
The authors investigate a prototype 3-lens f/1 catadioptric camera, built in 1934 by the famous optician Bernhard Schmidt at the Hamburg-Bergedorf Observatory in Germany, where Schmidt worked before his death in 1935. The prototype is in the observatory's collection of Schmidt artifacts, but its nature was not understood before the authors' recent examination. It is an astronomical camera of a form known as 'Buchroeder-Houghton', consisting of a spherical mirror and a 3-element afocal corrector lens placed at the mirror's center of curvature. The design is named for R.A. Buchroeder and J.L. Houghton who independently published this and related forms of wide-field spherical-lens cameras after 1942. Schmidt died before he could publish his own design. The authors disassembled the prototype and measured its optical parameters. These they present together with a transmission test of the corrector lens. The authors also consider the theoretical performance of the design as built, the theory of Houghton cameras, Schmidt's possible path to his invention, and the place of the prototype in his scientific output.
Chronicle of Higher Education. Volume 51, Number 24, February 18, 2005
ERIC Educational Resources Information Center
Chronicle of Higher Education, 2005
2005-01-01
"Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This February 18, 2005 issue of "Chronicle for Higher Education" includes the following articles: (1) "From Special Ed to Higher Ed" (Schmidt, Peter); (2) "University…
NASA Astrophysics Data System (ADS)
Li, Yinan; Qiao, Youming; Wang, Xin; Duan, Runyao
2018-03-01
We study the problem of transforming a tripartite pure state to a bipartite one using stochastic local operations and classical communication (SLOCC). It is known that the tripartite-to-bipartite SLOCC convertibility is characterized by the maximal Schmidt rank of the given tripartite state, i.e. the largest Schmidt rank over those bipartite states lying in the support of the reduced density operator. In this paper, we further study this problem and exhibit novel results in both multi-copy and asymptotic settings, utilizing powerful results from the structure of matrix spaces. In the multi-copy regime, we observe that the maximal Schmidt rank is strictly super-multiplicative, i.e. the maximal Schmidt rank of the tensor product of two tripartite pure states can be strictly larger than the product of their maximal Schmidt ranks. We then provide a full characterization of those tripartite states whose maximal Schmidt rank is strictly super-multiplicative when taking tensor product with itself. Notice that such tripartite states admit strict advantages in tripartite-to-bipartite SLOCC transformation when multiple copies are provided. In the asymptotic setting, we focus on determining the tripartite-to-bipartite SLOCC entanglement transformation rate. Computing this rate turns out to be equivalent to computing the asymptotic maximal Schmidt rank of the tripartite state, defined as the regularization of its maximal Schmidt rank. Despite the difficulty caused by the super-multiplicative property, we provide explicit formulas for evaluating the asymptotic maximal Schmidt ranks of two important families of tripartite pure states by resorting to certain results of the structure of matrix spaces, including the study of matrix semi-invariants. These formulas turn out to be powerful enough to give a sufficient and necessary condition to determine whether a given tripartite pure state can be transformed to the bipartite maximally entangled state under SLOCC, in the asymptotic setting. Applying the recent progress on the non-commutative rank problem, we can verify this condition in deterministic polynomial time.
Mixing in High Schmidt Number Turbulent Jets
1991-01-01
the higher Sc jet is less well mixed. The difference is less pronounced at higher Re. Flame length estimates imply either an increase in entrainment...72 8.0 Estimation of flame lengths ....................................... 74 8.1 Estim ation m...A.4) Lf flame length N number of trials (Eq. 3.1) p exponent in fits of the variance behavior with Re p probability of a binomial event (Eq. 3.1) p
Manipulation of a two-photon state in a χ(2)-modulated nonlinear waveguide array
NASA Astrophysics Data System (ADS)
Yang, Y.; Xu, P.; Lu, L. L.; Zhu, S. N.
2014-10-01
We propose to engineer the quantum state in a high-dimensional Hilbert space by taking advantage of a χ(2)-modulated nonlinear waveguide array. By varying the pump condition and the waveguide array length, the momentum correlation between the signal and idler photons can be manipulated, exhibiting bunching, antibunching, and the evolution between these two states, which are characterized by the Schmidt number. We find the Schmidt number is dependent on a structure parameter, namely the ratio of the array length and the number of channels pumped. By designing the linear profile waveguide array, the degree of spatial entanglement shows a periodic relationship with the slope of linear profile, during which a high degree of position-bunching state is suggested. The two-photon self-focusing effect is disclosed when the χ(2) modulation in the waveguide array contains a parabolic profile, which can be designed for efficient coupling between a waveguide array and fibers. These results shed light on a feasible way to achieve desirable quantum state on a single waveguide chip by a compact engineering of χ(2) and also suggest a degree of freedom for quantum walk and other related applications.
Active Thrusting and Earthquake Recurrence Near Aksu, Southern Tianshan
NASA Astrophysics Data System (ADS)
Hubert-Ferrari, A.; Suppe, J.; van der Woerd, J.; Wang, Xin
The 'Berlin Exoplanet Search Telescope' (BEST) is a small aperture (20cm), wide- field, Schmidt-telescope for detection of close-in Jupiter-sized exoplanets in edge-on orbits of Sun-like stars. The field-of-view of the telescope, equipped with a 2k CCD, is around 3 x 3 degrees, allowing a large number of stars (>20000) to be observed simultaneously in a typical field centered in the galactic plane. Regular observations of several fields have started in July 2001 at the 'Thüringer Landessternwarte Tauten- burg', Germany. We also used this telescope to observe the known planetary transits across the star HD 209458 (Charbonneau et al., 2000) to demonstrate the detection capabili- ties of the instrument. These observations and first results of the ongoing regular field observations will be presented.
The statistics of gravitational lenses. III - Astrophysical consequences of quasar lensing
NASA Technical Reports Server (NTRS)
Ostriker, J. P.; Vietri, M.
1986-01-01
The method of Schmidt and Green (1983) for calculating the luminosity function of quasars is combined with gravitational-lensing theory to compute expected properties of lensed systems. Multiple quasar images produced by galaxies are of order 0.001 of the observed quasars, with the numbers over the whole sky calculated to be (0.86, 120, 1600) to limiting B magnitudes of (16, 19, 22). The amount of 'false evolution' is small except for an interesting subset of apparently bright, large-redshift objects for which minilensing by starlike objects may be important. Some of the BL Lac objects may be in this category, with the galaxy identified as the parent object really a foreground object within which stars have lensed a background optically violent variable quasar.
Future-Minded: Aaron Schmidt--Thomas Ford Memorial Library, IL
ERIC Educational Resources Information Center
Library Journal, 2005
2005-01-01
Like many young people, Aaron Schmidt loves electronic gadgets. But not for their own sake. He believes the future of libraries depends on how well we meet the needs of today's young adults, who are far more tech-fluent than most librarians. As reference librarian and all-around technology guru at Thomas Ford Memorial Library, Schmidt created the…
Pla, Davinia; Sanz, Libia; Whiteley, Gareth; Wagstaff, Simon C; Harrison, Robert A; Casewell, Nicholas R; Calvete, Juan J
2017-04-01
Non-front-fanged colubroid snakes comprise about two-thirds of extant ophidian species. The medical significance of the majority of these snakes is unknown, but at least five species have caused life-threatening or fatal human envenomings. However, the venoms of only a small number of species have been explored. A combined venomic and venom gland transcriptomic approach was employed to characterise of venom of Dispholidus typus (boomslang), the snake that caused the tragic death of Professor Karl Patterson Schmidt. The ability of CroFab™ antivenom to immunocapture boomslang venom proteins was investigated using antivenomics. Transcriptomic-assisted proteomic analysis identified venom proteins belonging to seven protein families: three-finger toxin (3FTx); phospholipase A 2 (PLA 2 ); cysteine-rich secretory proteins (CRISP); snake venom (SV) serine proteinase (SP); C-type lectin-like (CTL); SV metalloproteinases (SVMPs); and disintegrin-like/cysteine-rich (DC) proteolytic fragments. CroFab™ antivenom efficiently immunodepleted some boomslang SVMPs. The present work is the first to address the overall proteomic profile of D. typus venom. This study allowed us to correlate the toxin composition with the toxic activities of the venom. The antivenomic analysis suggested that the antivenom available at the time of the unfortunate accident could have exhibited at least some immunoreactivity against the boomslang SVMPs responsible for the disseminated intravascular coagulation syndrome that caused K.P. Schmidt's fatal outcome. This study may stimulate further research on other non-front-fanged colubroid snake venoms capable of causing life-threatening envenomings to humans, which in turn should contribute to prevent fatal human accidents, such as that unfortunately suffered by K.P. Schmidt. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slater, Paul B.
Paralleling our recent computationally intensive (quasi-Monte Carlo) work for the case N=4 (e-print quant-ph/0308037), we undertake the task for N=6 of computing to high numerical accuracy, the formulas of Sommers and Zyczkowski (e-print quant-ph/0304041) for the (N{sup 2}-1)-dimensional volume and (N{sup 2}-2)-dimensional hyperarea of the (separable and nonseparable) NxN density matrices, based on the Bures (minimal monotone) metric--and also their analogous formulas (e-print quant-ph/0302197) for the (nonmonotone) flat Hilbert-Schmidt metric. With the same seven 10{sup 9} well-distributed ('low-discrepancy') sample points, we estimate the unknown volumes and hyperareas based on five additional (monotone) metrics of interest, including the Kubo-Mori and Wigner-Yanase.more » Further, we estimate all of these seven volume and seven hyperarea (unknown) quantities when restricted to the separable density matrices. The ratios of separable volumes (hyperareas) to separable plus nonseparable volumes (hyperareas) yield estimates of the separability probabilities of generically rank-6 (rank-5) density matrices. The (rank-6) separability probabilities obtained based on the 35-dimensional volumes appear to be--independently of the metric (each of the seven inducing Haar measure) employed--twice as large as those (rank-5 ones) based on the 34-dimensional hyperareas. (An additional estimate--33.9982--of the ratio of the rank-6 Hilbert-Schmidt separability probability to the rank-4 one is quite clearly close to integral too.) The doubling relationship also appears to hold for the N=4 case for the Hilbert-Schmidt metric, but not the others. We fit simple exact formulas to our estimates of the Hilbert-Schmidt separable volumes and hyperareas in both the N=4 and N=6 cases.« less
NASA Technical Reports Server (NTRS)
Wegner, Gary A.
1987-01-01
Low resolution International Ultraviolet Explorer (IUE) spectroscopic observations of two magnetic white dwarfs BPM25114 and K813-14 were obtained using both the SWP and LWP cameras. The first object has an observed magnetic field of 4 x 10(7) Gauss and the second has one of 3 x 10(7) Gauss. Both objects have overall spectral energy distributions appropriate for cool DA white dwarfs with T(eff) near 10,000 K and accordingly show strong lambda lambda 1400 and 1600 absorption in their spectra. Compared to non-magnetic DA white dwarfs of comparable effective temperature, there are some differences in the profiles, presumably produced by the magnetic fields in these objects. In addition, the ultraviolet spectra of a number of hot subluminous stars in the Kiso Schmidt survey were observed.
What Makes Reading Difficult: The Complexity of Structures.
ERIC Educational Resources Information Center
Schmidt, Eunice L.
The original version of the "Helen Keller Story" and a linguistically more complex version of it were used to test the hypothesis that reading comprehension is affected by the complexity of linguistic structures. Complexity was measured by four readability measures, the mean number of words per T-unit, and the Schmidt-Kittrell Linguistic…
Electron diffusion deduced from eiscat
NASA Astrophysics Data System (ADS)
Roettger, J.; Fukao, S.
The EISCAT Svalbard Radar (ESR) operates on 500 MHz; collocated with it is the SOUSY Svalbard Radar (SSR), which operates on 53.5 MHz. We have used both radars during Polar Mesosphere Summer Echoes (PMSE) coherent scatter conditions, where the ESR can also detect incoherent scatter and thus allows to estimate the electron density. We describe obser-vations during two observing periods in summer 1999 and 2000. Well calibrated sig-nal power was obtained with both radars, from which we deduced the radar reflec-tivity. Estimating the turbulence dissipation rate from the narrow beam observations of PMSE with the ESR, using the estimate of the electron density and the radar reflec-tivity on both frequencies we can obtain estimates of the Schmidt number by compar-ing our observational results with the model of Cho and Kelley (1993). Schmidt num-bers of at least 100 are necessary to obtain the measured radar reflectivities, which ba-sically support the model of Cho and Kelley claiming that the inertial-viscous subrange in the electron gas can extend down to small scales of some ten centimeters (namely, the Bragg scale of the ESR).
Effect of homogenous-heterogeneous reactions on MHD Prandtl fluid flow over a stretching sheet
NASA Astrophysics Data System (ADS)
Khan, Imad; Malik, M. Y.; Hussain, Arif; Salahuddin, T.
An analysis is performed to explore the effects of homogenous-heterogeneous reactions on two-dimensional flow of Prandtl fluid over a stretching sheet. In present analysis, we used the developed model of homogeneous-heterogeneous reactions in boundary layer flow. The mathematical configuration of presented flow phenomenon yields the nonlinear partial differential equations. Using scaling transformations, the governing partial differential equations (momentum equation and homogenous-heterogeneous reactions equations) are transformed into non-linear ordinary differential equations (ODE's). Then, resulting non-linear ODE's are solved by computational scheme known as shooting method. The quantitative and qualitative manners of concerned physical quantities (velocity, concentration and drag force coefficient) are examined under prescribed physical constrained through figures and tables. It is observed that velocity profile enhances verses fluid parameters α and β while Hartmann number reduced it. The homogeneous and heterogeneous reactions parameters have reverse effects on concentration profile. Concentration profile shows retarding behavior for large values of Schmidt number. Skin fraction coefficient enhances with increment in Hartmann number H and fluid parameter α .
Modeling of Turbulent Free Shear Flows
NASA Technical Reports Server (NTRS)
Yoder, Dennis A.; DeBonis, James R.; Georgiadis, Nicolas J.
2013-01-01
The modeling of turbulent free shear flows is crucial to the simulation of many aerospace applications, yet often receives less attention than the modeling of wall boundary layers. Thus, while turbulence model development in general has proceeded very slowly in the past twenty years, progress for free shear flows has been even more so. This paper highlights some of the fundamental issues in modeling free shear flows for propulsion applications, presents a review of past modeling efforts, and identifies areas where further research is needed. Among the topics discussed are differences between planar and axisymmetric flows, development versus self-similar regions, the effect of compressibility and the evolution of compressibility corrections, the effect of temperature on jets, and the significance of turbulent Prandtl and Schmidt numbers for reacting shear flows. Large eddy simulation greatly reduces the amount of empiricism in the physical modeling, but is sensitive to a number of numerical issues. This paper includes an overview of the importance of numerical scheme, mesh resolution, boundary treatment, sub-grid modeling, and filtering in conducting a successful simulation.
Schmidt's syndrome: a rare cause of puberty menorrhagia.
Sharma, J B; Tiwari, S; Gulati, N; Sharma, S
1990-12-01
Schmidt's syndrome, also known as polyglandular deficiency syndrome, is the presence of Addison's disease and hypothyrodism in a single patient. It is usually associated with other autoimmune disorders like vitiligo, diabetes mellitus, myasthenia gravis. A rare case of an 18-year-old girl having Schmidt's syndrome and vitiligo who presented with puberty menorrhagia is reported. A brief review of the literature is also given.
Gram-Schmidt algorithms for covariance propagation
NASA Technical Reports Server (NTRS)
Thornton, C. L.; Bierman, G. J.
1977-01-01
This paper addresses the time propagation of triangular covariance factors. Attention is focused on the square-root free factorization, P = UD(transpose of U), where U is unit upper triangular and D is diagonal. An efficient and reliable algorithm for U-D propagation is derived which employs Gram-Schmidt orthogonalization. Partitioning the state vector to distinguish bias and coloured process noise parameters increase mapping efficiency. Cost comparisons of the U-D, Schmidt square-root covariance and conventional covariance propagation methods are made using weighted arithmetic operation counts. The U-D time update is shown to be less costly than the Schmidt method; and, except in unusual circumstances, it is within 20% of the cost of conventional propagation.
Gram-Schmidt algorithms for covariance propagation
NASA Technical Reports Server (NTRS)
Thornton, C. L.; Bierman, G. J.
1975-01-01
This paper addresses the time propagation of triangular covariance factors. Attention is focused on the square-root free factorization, P = UDU/T/, where U is unit upper triangular and D is diagonal. An efficient and reliable algorithm for U-D propagation is derived which employs Gram-Schmidt orthogonalization. Partitioning the state vector to distinguish bias and colored process noise parameters increases mapping efficiency. Cost comparisons of the U-D, Schmidt square-root covariance and conventional covariance propagation methods are made using weighted arithmetic operation counts. The U-D time update is shown to be less costly than the Schmidt method; and, except in unusual circumstances, it is within 20% of the cost of conventional propagation.
On Hilbert-Schmidt norm convergence of Galerkin approximation for operator Riccati equations
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1988-01-01
An abstract approximation framework for the solution of operator algebraic Riccati equations is developed. The approach taken is based on a formulation of the Riccati equation as an abstract nonlinear operator equation on the space of Hilbert-Schmidt operators. Hilbert-Schmidt norm convergence of solutions to generic finite dimensional Galerkin approximations to the Riccati equation to the solution of the original infinite dimensional problem is argued. The application of the general theory is illustrated via an operator Riccati equation arising in the linear-quadratic design of an optimal feedback control law for a 1-D heat/diffusion equation. Numerical results demonstrating the convergence of the associated Hilbert-Schmidt kernels are included.
Plume structure in high-Rayleigh-number convection
NASA Astrophysics Data System (ADS)
Puthenveettil, Baburaj A.; Arakeri, Jaywant H.
2005-10-01
Near-wall structures in turbulent natural convection at Rayleigh numbers of 10^{10} to 10^{11} at A Schmidt number of 602 are visualized by a new method of driving the convection across a fine membrane using concentration differences of sodium chloride. The visualizations show the near-wall flow to consist of sheet plumes. A wide variety of large-scale flow cells, scaling with the cross-section dimension, are observed. Multiple large-scale flow cells are seen at aspect ratio (AR)= 0.65, while only a single circulation cell is detected at AR= 0.435. The cells (or the mean wind) are driven by plumes coming together to form columns of rising lighter fluid. The wind in turn aligns the sheet plumes along the direction of shear. the mean wind direction is seen to change with time. The near-wall dynamics show plumes initiated at points, which elongate to form sheets and then merge. Increase in rayleigh number results in a larger number of closely and regularly spaced plumes. The plume spacings show a common log normal probability distribution function, independent of the rayleigh number and the aspect ratio. We propose that the near-wall structure is made of laminar natural-convection boundary layers, which become unstable to give rise to sheet plumes, and show that the predictions of a model constructed on this hypothesis match the experiments. Based on these findings, we conclude that in the presence of a mean wind, the local near-wall boundary layers associated with each sheet plume in high-rayleigh-number turbulent natural convection are likely to be laminar mixed convection type.
ERIC Educational Resources Information Center
Hough, Susan L.; Hall, Bruce W.
The meta-analytic techniques of G. V. Glass (1976) and J. E. Hunter and F. L. Schmidt (1977) were compared through their application to three meta-analytic studies from education literature. The following hypotheses were explored: (1) the overall mean effect size would be larger in a Hunter-Schmidt meta-analysis (HSMA) than in a Glass…
Development of Targeted Therapeutic Agents for Botulism
2001-02-01
peptides previously prepared by Schmidt & Bostian (1997) [where changes were made to a C-terminal 17-mer (187-203) of SNAP-25], attention was focussed here...arrest of intoxication with inhibitors (being prepared 8 successfully by Dr. J. Schmidt at USAMRIID; Schmidt et al., 1998) whilst replenshing the toxic...purified on the immobilised immunogen. Urografin (Schering Healthcare, G.D.R.), digitonin (Novabiochem, U.K.), radio -immunoassay (RIA) kit for human growth
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Jie; Wang, Xin, E-mail: wangx@tongji.edu.cn, E-mail: mubz@tongji.edu.cn; Zhan, Qi
This paper presents a novel lobster-eye imaging system for X-ray-backscattering inspection. The system was designed by modifying the Schmidt geometry into a treble-lens structure in order to reduce the resolution difference between the vertical and horizontal directions, as indicated by ray-tracing simulations. The lobster-eye X-ray imaging system is capable of operating over a wide range of photon energies up to 100 keV. In addition, the optics of the lobster-eye X-ray imaging system was tested to verify that they meet the requirements. X-ray-backscattering imaging experiments were performed in which T-shaped polymethyl-methacrylate objects were imaged by the lobster-eye X-ray imaging system basedmore » on both the double-lens and treble-lens Schmidt objectives. The results show similar resolution of the treble-lens Schmidt objective in both the vertical and horizontal directions. Moreover, imaging experiments were performed using a second treble-lens Schmidt objective with higher resolution. The results show that for a field of view of over 200 mm and with a 500 mm object distance, this lobster-eye X-ray imaging system based on a treble-lens Schmidt objective offers a spatial resolution of approximately 3 mm.« less
NASA Astrophysics Data System (ADS)
Xu, Jie; Wang, Xin; Zhan, Qi; Huang, Shengling; Chen, Yifan; Mu, Baozhong
2016-07-01
This paper presents a novel lobster-eye imaging system for X-ray-backscattering inspection. The system was designed by modifying the Schmidt geometry into a treble-lens structure in order to reduce the resolution difference between the vertical and horizontal directions, as indicated by ray-tracing simulations. The lobster-eye X-ray imaging system is capable of operating over a wide range of photon energies up to 100 keV. In addition, the optics of the lobster-eye X-ray imaging system was tested to verify that they meet the requirements. X-ray-backscattering imaging experiments were performed in which T-shaped polymethyl-methacrylate objects were imaged by the lobster-eye X-ray imaging system based on both the double-lens and treble-lens Schmidt objectives. The results show similar resolution of the treble-lens Schmidt objective in both the vertical and horizontal directions. Moreover, imaging experiments were performed using a second treble-lens Schmidt objective with higher resolution. The results show that for a field of view of over 200 mm and with a 500 mm object distance, this lobster-eye X-ray imaging system based on a treble-lens Schmidt objective offers a spatial resolution of approximately 3 mm.
Compressibility effects on turbulent mixing
NASA Astrophysics Data System (ADS)
Panickacheril John, John; Donzis, Diego
2016-11-01
We investigate the effect of compressibility on passive scalar mixing in isotropic turbulence with a focus on the fundamental mechanisms that are responsible for such effects using a large Direct Numerical Simulation (DNS) database. The database includes simulations with Taylor Reynolds number (Rλ) up to 100, turbulent Mach number (Mt) between 0.1 and 0.6 and Schmidt number (Sc) from 0.5 to 1.0. We present several measures of mixing efficiency on different canonical flows to robustly identify compressibility effects. We found that, like shear layers, mixing is reduced as Mach number increases. However, data also reveal a non-monotonic trend with Mt. To assess directly the effect of dilatational motions we also present results with both dilatational and soleniodal forcing. Analysis suggests that a small fraction of dilatational forcing decreases mixing time at higher Mt. Scalar spectra collapse when normalized by Batchelor variables which suggests that a compressive mechanism similar to Batchelor mixing in incompressible flows might be responsible for better mixing at high Mt and with dilatational forcing compared to pure solenoidal mixing. We also present results on scalar budgets, in particular on production and dissipation. Support from NSF is gratefully acknowledged.
Collaborative Oceanographic Research Opportunities with Schmidt Ocean Institute
NASA Astrophysics Data System (ADS)
Zykov, V.
2014-12-01
Schmidt Ocean Institute (http://www.schmidtocean.org/) was founded by Dr. Eric Schmidt and Wendy Schmidt in 2009 to support frontier oceanographic research and exploration to expand the understanding of the world's oceans through technological advancement, intelligent, data-rich observation and analysis, and open sharing of information. Schmidt Ocean Institute operates a state-of-the-art globally capable research vessel Falkor (http://www.schmidtocean.org/story/show/47). After two years of scientific operations in the Atlantic Ocean, Gulf of Mexico, Caribbean, Eastern and Central Pacific, R/V Falkor is now preparing to support research in the Western Pacific and Eastern Indian Oceans in 2015 and 2016. As part of the long term research program development for Schmidt Ocean Institute, we aim to identify initiatives and projects that demonstrate strong alignment with our strategic interests. We focus on scientific opportunities that highlight effective use of innovative technologies to better understand the oceans, such as, for example, research enabled with remotely operated and autonomous vehicles, acoustics, in-situ sensing, telepresence, etc. Our technology-first approach to ocean science gave rise to infrastructure development initiatives, such as the development of a new full ocean depth Hybrid Remotely Operated Vehicle, new 6000m scientific Autonomous Underwater Vehicle, live HD video streaming from the ship to YouTube, shipboard high performance supercomputing, etc. We also support projects focusing on oceanographic technology research and development onboard R/V Falkor. We provide our collaborators with access to all of R/V Falkor's facilities and instrumentation in exchange for a commitment to make the resulting scientific data openly available to the international oceanographic community. This presentation aims to expand awareness about the interests and capabilities of Schmidt Ocean Institute and R/V Falkor among our scientific audiences and further develop the network of our research collaborations. We would also like to inform interested scientists and technology developers about our program development and proposal selection processes and explain how they can participate in future collaborations with Schmidt Ocean Institute.
2016-08-01
OXYGEN IN ATMOSPHERIC PRESSURE PLASMAS James D. Scofield (AFRL/RQQE) and James R. Gord (AFRL/RQTC) Electrical Systems Branch, Power and Control...Division (AFRL/RQQE) Combustion Branch, Turbine Engine Division (AFRL/RQTC) Jacob B. Schmidt and Sukesh Roy Spectral Energies LLC Brian Sands...LASER-INDUCED FLUORESCENCE (TALIF) OF ATOMIC OXYGEN IN ATMOSPHERIC PRESSURE PLASMAS 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM
NASA Astrophysics Data System (ADS)
Nagaosa, Ryuichi S.
2014-08-01
This paper proposes a new numerical modelling to examine environmental chemodynamics of a gaseous material exchanged between the air and turbulent water phases across a gas-liquid interface, followed by an aquarium chemical reaction. This study uses an extended concept of a two-compartment model, and assumes two physicochemical substeps to approximate the gas exchange processes. The first substep is the gas-liquid equilibrium between the air and water phases, A(g)⇌A(aq), with Henry's law constant H. The second is a first-order irreversible chemical reaction in turbulent water, A(aq)+H2O→B(aq)+H+ with a chemical reaction rate κA. A direct numerical simulation (DNS) technique has been employed to obtain details of the gas exchange mechanisms and the chemical reaction in the water compartment, while zero velocity and uniform concentration of A is considered in the air compartment. The study uses the different Schmidt numbers between 1 and 8, and six nondimensional chemical reaction rates between 10(≈0) to 101 at a fixed Reynolds number. It focuses on the effects of the Schmidt number and the chemical reaction rate on fundamental mechanisms of the gas exchange processes across the interface.
2012-09-30
results of running it on the GLINT10 AUV Unicorn dataset is given in Fig. 3. This figure is a histogram which shows the number of messages from the...as well as Non- Government Institutions such as Battelle Memorial Institute. PUBLICATIONS 1. T. Schneider and H. Schmidt, "Goby-Acomms
Assessing Soldier Individual Differences to Enable Tailored Training
2010-04-01
upon effective and efficient training. However, there is ample evidence that learning-related individual differences exist ( Thorndike , 1985; Jensen...in both civilian and military settings (Schmidt, Hunter, & Outerbridge, 1986; Thorndike , 1985). Prior knowledge or knowledge of facts and...predictive power ( Thorndike , 1985; Jensen, 1998). Further, there is a good deal of evidence that general mental ability impacts performance largely
Exploring Learner Perception and Use of Task-Based Interactional Feedback in FTF and CMC Modes
ERIC Educational Resources Information Center
Gurzynski-Weiss, Laura; Baralt, Melissa
2014-01-01
Theoretical claims about the benefits of corrective feedback have been largely premised on learners' noticing of feedback (e.g., Gass & Mackey, 2006; Long, 1996; Schmidt, 1990, 1995; Swain, 1995), and findings have demonstrated that both the feedback target (Mackey, Gass, & McDonough, 2000) and the mode of provision (Lai & Zhao,…
2015-10-01
clinton.murray@us.army.mil 16 Gregory Altman Surgeon AGY altmangregory@hotmail.com; GALTMAN@wpahs.org Andrew Schmidt Surgeon HCM schmi115...CMC 601 209 180 48 1 16 1 UWA 289 224 115 48 3 0 1 VMC 477 159 56 38 1 3 1 HRV 388 - 52 33 3 0 4 AGY 448 - 38 20 2 4 1 MTH 398 154 67 17 2 1 1 YRK...Number Number Number Number Certified Screened Screened Eligible Enrolled Refused Not Enrolled ALL 1304 733 (56%) 427 (58%) 97 (13%) 209 (29%) AGY 448
Labrude, Pierre
2017-03-01
Henri Schmidt was, with his fellow the senator Paul Cazeneuve, the main defender of the mention of pharmacists and pharmacy students in the articles of the law voted in 1913 for the recruitment of the army. After the description of their interventions to attain this end, and a short biography of these two politicians, the paper explains the activities of the pharmaceutical parliamentary group, during the early years of the war, in view to obtain the admittance in the medical corps of the pharmacists and students unprovided of rank, for the new creation of «auxiliary pharmacists», for the appointment as soon as possible of the maximum number of colleagues at this rank, and then for their promotion to the rank of «aide-major», resolution that appeared more difficult to obtain.
The Tactical Center of Gravity: How Useful is the Concept?
1990-01-06
through the Huertgen Forest, across the Kall River, capture the town of Kommerscheidt, and then capture Schmidt. The regiment also was required to protect...south through the woods, cross country to the Kall River, to take Kommerscheidt. The 3rd Battalion was to follow the 1st Battalion and take Schmidt on...desperate struggle. The lead battalions were destroyed piecemeal by the Germans in Kommerscheidt and Schmidt and along the Kall Trail. Poor
NASA Astrophysics Data System (ADS)
Bhathal, Ragbir
2012-02-01
Brian Schmidt was awarded the Nobel Prize for Physics in 2011 along with Saul Perlmutter and Adam Riess. He is a Fellow of the Australian Academy of Science and of the US National Academy of Sciences. Schmidt has made significant contributions in observational cosmology, supernovae, gamma-ray bursts and all-sky surveys. Ragbir Bhathal interviewed him in 2006 for the National Oral History Project on significant Australian Astronomers sponsored by the National Library of Australia. (Photos: Belinda Pratten)
Mixing of a passive scalar by the instability of a differentially rotating axial pinch
NASA Astrophysics Data System (ADS)
Paredes, A.; Gellert, M.; Rüdiger, G.
2016-04-01
The mean-field diffusion of passive scalars such as lithium, beryllium or temperature dispersals due to the magnetic Tayler instability of a rotating axial pinch is considered. Our study is carried out within a Taylor-Couette setup for two rotation laws: solid-body quasi-Kepler rotation. The minimum magnetic Prandtl number used is 0.05, and the molecular Schmidt number Sc of the fluid varies between 0.1 and 2. An effective diffusivity coefficient for the mixing is numerically measured by the decay of a prescribed concentration peak located between both cylinder walls. We find that only models with Sc exceeding 0.1 basically provide finite instability-induced diffusivity values. We also find that for quasi-Kepler rotation at a magnetic Mach number Mm ≃ 2, the flow transits from the slow-rotation regime to the fast-rotation regime that is dominated by the Taylor-Proudman theorem. For fixed Reynolds number, the relation between the normalized turbulent diffusivity and the Schmidt number of the fluid is always linear so that also a linear relation between the instability-induced diffusivity and the molecular viscosity results, just in the sense proposed by Schatzman (1977, A&A, 573, 80). The numerical value of the coefficient in this relation reaches a maximum at Mm ≃ 2 and decreases for larger Mm, implying that only toroidal magnetic fields on the order of 1 kG can exist in the solar tachocline.
Kahn Bani Sa’ad Correctional Facility, Kahn Bani Sa’ad, Iraq
2008-07-25
building (Building No. 07/03): 1. Ground floor columns were tested with a Schmidt hammer devise (measures the elastic properties or strength of...3. First floor columns – Schmidt hammer and ultrasonic tests were conducted on all the first floor columns. The test results showed the strength...Building Nos. 07/02 and 07/01): 1. Ground floor columns – Using a Schmidt hammer device, very few columns showed low strength. Further study and
"I No Say You Say Is Boring": The Development of Pragmatic Competence in L2 Apology
ERIC Educational Resources Information Center
Chang, Yuh-Fang
2010-01-01
While the number of studies on pragmatic development has been increasing since Kasper and Schmidt's call for more research into this under-researched area (e.g., [Barron, A., 2003. Acquisition in Interlanguage Pragmatics: Learning How to do Things with Words in a Study Abroad Context. Benhamins, Amsterdam; Achiba, M., 2003. Learning to Request in…
Military Suicide Research Consortium
2015-10-01
physical and sexual abuse and lifetime number of suicide attempts: A persistent and theoretically important relationship. Behaviour Research & Therapy ...meeting of the Association of Behavioral and Cognitive Therapies , Chicago, IL. Norr, A. M., Allan, N. P., Macatee, R. J., Capron, D. W., & Schmidt, N. B...presentation to the annual Association for Behavioral and Cognitive Therapies conference, Chicago, IL. >>Dr. Craig Bryan had the following: Bryan, C.J
Geometric Computation of Human Gyrification Indexes from Magnetic Resonance Images
2009-04-01
GEOMETRIC COMPUTATION OF HUMAN GYRIFICATION INDEXES FROM MAGNETIC RESONANCE IMAGES By Shu Su Tonya White Marcus Schmidt Chiu-Yen Kao and Guillermo...00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Geometric Computation of Human Gyrification Indexes from Magnetic Resonance Images 5a. CONTRACT NUMBER... Geometric Computation of Gyrification Indexes Chiu-Yen Kao 1 Geometric Computation of Human Gyrification
Data processing from lobster eye type optics
NASA Astrophysics Data System (ADS)
Nentvich, Ondrej; Stehlikova, Veronika; Urban, Martin; Hudec, Rene; Sieger, Ladislav
2017-05-01
Wolter I optics are commonly used for imaging in X-Ray spectrum. This system uses two reflections, and at higher energies, this system is not so much efficient but has a very good optical resolution. Here is another type of optics Lobster Eye, which is using also two reflections for focusing rays in Schmidt's or Angel's arrangement. Here is also possible to use Lobster eye optics as two one dimensional independent optics. This paper describes advantages of one dimensional and two dimensional Lobster Eye optics in Schmidt's arrangement and its data processing - find out a number of sources in wide field of view. Two dimensional (2D) optics are suitable to detect the number of point X-ray sources and their magnitude, but it is necessary to expose for a long time because a 2D system has much lower transitivity, due to double reflection, compared to one dimensional (1D) optics. Not only for this reason, two 1D optics are better to use for lower magnitudes of sources. In this case, additional image processing is necessary to achieve a 2D image. This article describes of approach an image reconstruction and advantages of two 1D optics without significant losses of transitivity.
Himmelsfotografie MIT Schmidt-Teleskopen
NASA Astrophysics Data System (ADS)
Marx, Siegfried; Pfau, Werner
Auf dem Höhepunkt der Verbreitung und astronomischen Anwendung von Schmidt-Teleskopen legen S. Marx und W. Pfau einen reich illustrierten Bildband zu diesem Fernrohrtyp vor. Der thematische Bogen reicht von der Teleskoptechnik und ihrer Geschichte über das Leben von Berhard Schmidt bis zu den schönsten, hier in hervorragender Qualität wiedergegebenen Himmelsaufnahmen und ihrer wissenschaftlichen Interpretation. Praktische Hinweise zu eigener fotografischer Tätigkeit und ein Glossar machen das Buch nützlich für jeden Liebhaber der Himmelskunde.
NASA Astrophysics Data System (ADS)
Abdulhadi, Ahmed M.; Ahmed, Tamara S.
2018-05-01
In this paper, we deals with the impact of radialiy magnetic field on the peristaltic transport of Jeffrey fluid through a curved channel with two dimensional. The effect of slip condition on velocity, the non-slip condition on temperature and conversation is performed. The heat and mass transfer are considered under the influence of various parameters. The flow is investigated under the assumption of long wave length and low Reynolds number approximations. The distribution of temperature and concentration are discussed for various parameters governing the flow with the simultaneous effects of Brinkman number, Soret number and Schmidt number.
Innovative space x-ray telescopes
NASA Astrophysics Data System (ADS)
Hudec, R.; Inneman, A.; Pina, L.; Sveda, L.; Ticha, H.; Brozek, V.
2017-11-01
We report on the progress in innovative X-ray mirror development with focus on requirements of future X-ray astronomy space projects. Various future projects in X-ray astronomy and astrophysics will require large lightweight but highly accurate segments with multiple thin shells or foils. The large Wolter 1 grazing incidence multiple mirror arrays, the Kirkpatrick-Baez modules, as well as the large Lobster-Eye X-ray telescope modules in Schmidt arrangement may serve as examples. All these space projects will require high quality and light segmented shells (shaped, bent or flat foils) with high X-ray reflectivity and excellent mechanical stability.
NASA Astrophysics Data System (ADS)
Sturgess, G. J.; Syed, S. A.
1982-06-01
A numerical simulation is made of the flow in the Wright Aeronautical Propulsion Laboratory diffusion flame research combustor operating with a strong central jet of carbon dioxide in a weak and removed co-axial jet of air. The simulation is based on a finite difference solution of the time-average, steady-state, elliptic form of the Reynolds equations. Closure for these equations is provided by a two-equation turbulence model. Comparisons between measurements and predictions are made for centerline axial velocities and radial profiles of CO2 concentration. Earlier findings for a single specie, constant density, single jet flow that a large expansion ratio confined jet behaves initially as if it were unconfined, are confirmed for the multiple-specie, variable density, multiple-jet system. The lack of universality in the turbulence model constants and the turbulent Schmidt/Prandtl number is discussed.
NASA Astrophysics Data System (ADS)
Schmidt, B.; Dyl, K.
2014-07-01
The mid-outer main belt is rich in possible parent bodies for the water-bearing carbonaceous chondrites, given their dark surfaces and frequent presence of hydrated minerals (e.g., Feierberg et al. 1985). Ceres (Thomas et al. 2005) and Pallas (Schmidt et al. 2009) possess shapes that indicate that these bodies have achieved hydrostatic equilibrium and may be differentiated (rock from ice). Dynamical calculations suggest asteroids formed rapidly to large sizes to produce the size frequency distribution within today's main belt (e.g., Morbidelli et al. 2009). Water-ice bound to organics has now been detected on the surface of Themis (Rivkin and Emery 2009, Campins et al. 2009), and indirect evidence for ice on many of the remaining family members, including main-belt comets (Hsieh & Jewitt 2006, Castillo-Rogez & Schmidt 2010), supports the theory that the ''C-class'' asteroids formed early and ice-rich. The carbonaceous chondrites represent a rich history of the thermal and aqueous evolution of early planetesimals (e.g., McSween 1979, Bunch and Chang, 1980, Zolensky and McSween 1988, Clayton 1993, Rowe et al., 1994). The composition of these meteorites reflects the timing and duration of water flow, as well as subsequent mineral alteration and isotopic evolution that can constrain temperature and water-rock ratios in which these systematics were set (e.g., Young et al. 1999, Dyl et al. 2012). Debate exists as to how the chemical and thermal consequences of fluid flow on carbonaceous chondrite parent bodies relate to parent-body characteristics: small, static water bodies (e.g., McSween 1979); small, convecting but homogeneous bodies (e.g., Young et al. 1999, 2003); or larger convecting bodies (e.g., Grimm and McSween 1989, Palguta et al. 2010). Heterogeneous thermal and aqueous evolution on larger asteroids that suggests more than one class of carbonaceous chondrite may be produced on the same body (e.g., Castillo-Rogez & Schmidt 2010, Elkins-Tanton et al. 2011, Schmidt & Castillo-Rogez 2012) if the chemical consequences can be reconciled (e.g., Young 2001, Young et al. 2003). Both models (Schmidt and Castillo-Rogez 2012) and experiments (e.g., Hiroi et al. 1996) suggest that water loss from asteroids is an important factor in interpreting the connections between the C-class asteroids and meteorites. The arrival of the Dawn spacecraft to Ceres will determine its much-debated internal structure and finally answer the following question: did large, icy planetesimals form and thermally evolve in the inner solar system? Even if Ceres is not icy, Dawn observations will shed light on its surface composition, and by extension on the surfaces of objects with similar surface properties. This presentation will focus on tying the observational evidence for water on evolving and contemporary asteroids with detailed studies of the carbonaceous chondrites in an effort to synthesize physical and chemical realities with the observational record, bridging the gap between the asteroid and meteorite communities.
NASA Astrophysics Data System (ADS)
Khan, Zeeshan; Khan, Ilyas; Ullah, Murad; Tlili, I.
2018-06-01
In this work, we discuss the unsteady flow of non-Newtonian fluid with the properties of heat source/sink in the presence of thermal radiation moving through a binary mixture embedded in a porous medium. The basic equations of motion including continuity, momentum, energy and concentration are simplified and solved analytically by using Homotopy Analysis Method (HAM). The energy and concentration fields are coupled with Dankohler and Schmidt numbers. By applying suitable transformation, the coupled nonlinear partial differential equations are converted to couple ordinary differential equations. The effect of physical parameters involved in the solutions of velocity, temperature and concentration profiles are discussed by assign numerical values and results obtained shows that the velocity, temperature and concentration profiles are influenced appreciably by the radiation parameter, Prandtl number, suction/injection parameter, reaction order index, solutal Grashof number and the thermal Grashof. It is observed that the non-Newtonian parameter H leads to an increase in the boundary layer thickness. It was established that the Prandtl number decreases thee thermal boundary layer thickness which helps in maintaining system temperature of the fluid flow. It is observed that the temperature profiles higher for heat source parameter and lower for heat sink parameter throughout the boundary layer. Fromm this simulation it is analyzed that an increase in the Schmidt number decreases the concentration boundary layer thickness. Additionally, for the sake of comparison numerical method (ND-Solve) and Adomian Decomposition Method are also applied and good agreement is found.
2017-05-22
Influence of postnatal glucocorticoids on hippocampal-dependent learning varies with elevation patterns and administration methods 5b. GRANT NUMBER...of these effects varies with the elevation patterns (level, duration, temporal fluctuation) achieved by different administration methods . In general...learning varies with elevation patterns and administration methods Dragana I. Claflin a, Kevin D. Schmidt a, Zachary D. Vallandingham b, Michal
Dynamic Spectrum Sharing with Limited Network State Information
2010-11-01
M. L. Honig,"Two-Cell Downlink Noncoherent Cooperation Without Transmitter Phase Alignment", Proc. Globecom Conf., Miami, FL, Dec. 2010. D. Schmidt, W...restrict the number of active streams even though the maximum multiplexing gain is not achieved. 3 Noncoherent Cooperative Broadcasting...study a noncoherent cooperative transmission scheme with two interfering links, which does not require phase alignment. It is assumed that the
Beacons in Time: Maarten Schmidt and the Discovery of Quasars.
ERIC Educational Resources Information Center
Preston, Richard
1988-01-01
Tells the story of Maarten Schmidt and the discovery of quasars. Discusses the decomposition of light, crucial observations and solving astronomical mysteries. Describes spectroscopic analysis used in astronomy and its application to quasars. (CW)
Cryogenic solid Schmidt camera as a base for future wide-field IR systems
NASA Astrophysics Data System (ADS)
Yudin, Alexey N.
2011-11-01
Work is focused on study of capability of solid Schmidt camera to serve as a wide-field infrared lens for aircraft system with whole sphere coverage, working in 8-14 um spectral range, coupled with spherical focal array of megapixel class. Designs of 16 mm f/0.2 lens with 60 and 90 degrees sensor diagonal are presented, their image quality is compared with conventional solid design. Achromatic design with significantly improved performance, containing enclosed soft correcting lens behind protective front lens is proposed. One of the main goals of the work is to estimate benefits from curved detector arrays in 8-14 um spectral range wide-field systems. Coupling of photodetector with solid Schmidt camera by means of frustrated total internal reflection is considered, with corresponding tolerance analysis. The whole lens, except front element, is considered to be cryogenic, with solid Schmidt unit to be flown by hydrogen for improvement of bulk transmission.
KWFC: four square degrees camera for the Kiso Schmidt Telescope
NASA Astrophysics Data System (ADS)
Sako, Shigeyuki; Aoki, Tsutomu; Doi, Mamoru; Ienaka, Nobuyuki; Kobayashi, Naoto; Matsunaga, Noriyuki; Mito, Hiroyuki; Miyata, Takashi; Morokuma, Tomoki; Nakada, Yoshikazu; Soyano, Takao; Tarusawa, Ken'ichi; Miyazaki, Satoshi; Nakata, Fumiaki; Okada, Norio; Sarugaku, Yuki; Richmond, Michael W.
2012-09-01
The Kiso Wide Field Camera (KWFC) is a facility instrument for the 105-cm Schmidt telescope being operated by the Kiso Observatory of the University of Tokyo. This camera has been designed for wide-field observations by taking advantage of a large focal-plane area of the Schmidt telescope. Eight CCD chips with a total of 8k x 8k pixels cover a field-of-view of 2.2 degrees x 2.2 degrees on the sky. The dewar window works as a field flattener lens minimizing an image distortion across the field of view. Two shutter plates moving in parallel achieve uniform exposures on all the CCD pixels. The KWFC is equipped with a filter exchanger composed of an industrial robotic arm, a filter magazine capable of storing 12 filters, and a filter holder at the focal plane. Both the arm and the magazine are installed inside the tube framework of the telescope but without vignetting the beam. Wide-field survey programs searching for supernovae and late-type variable stars have begun in April 2012. The survey observations are performed with a management software system for facility instruments including the telescope and the KWFC. This system automatically carries out observations based on target lists registered in advance and makes appropriate decisions for implementation of observations by referring to weather conditions and status of the instruments. Image data obtained in the surveys are processed with pipeline software in real time to search for candidates of time-variable sources.
Group analysis for natural convection from a vertical plate
NASA Astrophysics Data System (ADS)
Rashed, A. S.; Kassem, M. M.
2008-12-01
The steady laminar natural convection of a fluid having chemical reaction of order n past a semi-infinite vertical plate is considered. The solution of the problem by means of one-parameter group method reduces the number of independent variables by one leading to a system of nonlinear ordinary differential equations. Two different similarity transformations are found. In each case the set of differential equations are solved numerically using Runge-Kutta and the shooting method. For each transformation different Schmidt numbers and chemical reaction orders are tested.
NASA Astrophysics Data System (ADS)
Lagerkvist, C.-I.; Olofsson, K.; From, A.; Hammarback, G.; Magnusson, P.; Morell, O.
1985-01-01
In this paper we present 101 positions of asteroids obtained during Augnst 1982 with the GPO astrograph at ESO, Chile and with the Kvistaberg Schmidt telescope during September 1979 and February 1981.
NASA Astrophysics Data System (ADS)
Shakesby, Richard A.; Matthews, John A.; Owen, Geraint
2006-11-01
The Schmidt hammer is a relatively cheap, portable, sturdy instrument with proven value over the last two decades or so in rapidly dating coarse inorganic deposits of diverse origins. Early views were that its dating role was limited to distinguishing recently exposed from much older. Typically, either a few sites of possibly different ages or occasional older surfaces amongst many young sites were studied. More recently, calibration curves based on individual R-value means from small numbers (2-4) of sites of known ages have been used to estimate the ages of undated sites. We present Schmidt hammer rebound ( R-) values from 28 'Little Ice Age' (and younger), 23 Preboreal and 7 Younger Dryas glaciated surfaces in southern Norway in order, first, to test rigorously the robustness of the instrument as a relative-age dating tool. Despite being obtained from different surfaces (moraines, glaciofluvial deposits and bedrock) and varied metamorphic lithologies, the R-value overall means and 95% confidence intervals for the 'Little Ice Age', Preboreal and Younger Dryas age categories (respectively, 60.0±1.6, 41.6±1.4 and 34.2±2.0) are statistically significantly different. Only two outlying sites in the two younger age categories have overlapping confidence intervals, demonstrating remarkable robustness in differentiating early- and late-Holocene surfaces. The distinction between Preboreal and Younger Dryas sites (with terminal dates <2000 years apart) is less clear but still statistically significant, though possibly partly because of enhanced weathering conditions at the predominantly well vegetated Younger Dryas sites. Second, we examine the feasibility and desirability of controlling non-age-related factors, including some previously considered critical (instrument wear, operator bias, initial rock surface texture), which emerge either as less important than previously argued or as relatively unimportant, together with others previously unreported (e.g. long-term changes in lichen, soil, snow and vegetation covers). Third, we investigate the potential for calibrated-age dating by applying exploratory, linear rates of R-value decline to selected combinations of sites. The results suggest that error limits of ca ±700 to ±1600 years should be achievable over the Holocene timescale. This improved dating capability, however, will require adequate numbers of site means not only for each age category used to define these curves but also for each set of test surfaces of the same ages. Recommendations are made for a suitable sampling protocol for developing further the Schmidt hammer as a calibrated-age dating tool.
Bulk ZnO: Current Status, Challenges, and Prospects
2009-04-01
von Wenckstern, H. Schmidt, M. Lorenz, and M. Grundmann, “Defects in virgin and N+-implanted ZnO single crystals studied by positron annihilation...characterization, and device applications of semiconductor and complex oxide thin films. He is a co-author of more than 50 papers in referred...REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) < 1 Abstract— Rediscovered in the last decade, zinc oxide
Suppression of turbulent energy cascade due to phase separation in homogenous binary mixture fluid
NASA Astrophysics Data System (ADS)
Takagi, Youhei; Okamoto, Sachiya
2015-11-01
When a multi-component fluid mixture becomes themophysically unstable state by quenching from well-melting condition, phase separation due to spinodal decomposition occurs, and a self-organized structure is formed. During phase separation, free energy is consumed for the structure formation. In our previous report, the phase separation in homogenous turbulence was numerically simulated and the coarsening process of phase separation was discussed. In this study, we extended our numerical model to a high Schmidt number fluid corresponding to actual polymer solution. The governing equations were continuity, Navier-Stokes, and Chan-Hiliard equations as same as our previous report. The flow filed was an isotropic homogenous turbulence, and the dimensionless parameters in the Chan-Hilliard equation were estimated based on the thermophysical condition of binary mixture. From the numerical results, it was found that turbulent energy cascade was drastically suppressed in the inertial subrange by phase separation for the high Schmidt number flow. By using the identification of turbulent and phase separation structure, we discussed the relation between total energy balance and the structures formation processes. This study is financially supported by the Grand-in-Aid for Young Scientists (B) (No. T26820045) from the Ministry of Education, Cul-ture, Sports, Science and Technology of Japan.
Viscous dissipation impact on MHD free convection radiating fluid flow past a vertical porous plate
NASA Astrophysics Data System (ADS)
Raju, R. Srinivasa; Reddy, G. Jithender; Kumar, M. Anil
2018-05-01
An attempt has been made to study the radiation effects on unsteady MHD free convective flow of an incompressible fluid past an infinite vertical porous plate in the presence of viscous dissipation. The governing partial differential equations are solved numerically by using Galerkin finite element method. Computations were performed for a wide range of governing flow parameters viz., Magnetic Parameter, Schmidt number, Thermal radiation, Prandtl number, Eckert number and Permeability parameter. The effects of these flow parameters on velocity, temperature are shown graphically. In addition the local values of the Skin friction coefficient are shown in tabular form.
NASA Astrophysics Data System (ADS)
Hayat, T.; Khan, M. Waleed Ahmed; Khan, M. Ijaz; Waqas, M.; Alsaedi, A.
2018-06-01
Flow of magnetohydrodynamic (MHD) viscous fluid between two rotating disks is modeled. Angular velocities of two disks are different. Flow is investigated for nonlinear mixed convection. Heat transfer is analyzed for nonlinear thermal radiation and heat generation/absorption. Chemical reaction is also implemented. Convective conditions of heat and mass transfer are studied. Transformations used lead to reduction of PDEs into the ODEs. The impacts of important physical variables like Prandtl number, Reynold number, Hartman number, mixed convection parameter, chemical reaction and Schmidt number on velocities, temperature and concentration are elaborated. In addition velocity and temperature gradients are physically interpreted. Our obtained results indicate that radial, axial and tangential velocities decrease for higher estimation of Hartman number.
Orientation in birds. The sun compass.
Schmidt-Koenig, K; Ganzhorn, J U; Ranvaud, R
1991-01-01
The sun compass was discovered by G. Kramer in caged birds showing migratory restlessness. Subsequent experiments with caged birds employing directional training and clock shifts, carried out by Hoffman and Schmidt-Koenig, showed that the sun azimuth is used, and the sun altitude ignored. In the laboratory, McDonald found the accuracy to be +/- 3 degrees(-)+/- 5 degrees. According to Hoffmann and Schmidt-Koenig, caged birds trained at medium northern latitudes were able to allow for the sun's apparent movement north of the arctic circle, but not in equatorial and trans-equatorial latitudes. In homing experiments, and employing clock shifts, Schmidt-Koenig demonstrated that the sun compass is used by homing pigeons during initial orientation. This finding is the principal evidence for the existence of a map-and-compass navigational system. Pigeons living in equatorial latitudes utilize the sun compass even under the extreme solar conditions of equinox, achieving angular resolution of about 3 degrees in homing experiments. According to preliminary analyses, the homing pigeons' ephemerides are retarded by several weeks (Ranvaud, Schmidt-Koenig, Ganzhorn et al.).
A robotic reflective Schmidt telescope for Dome C
NASA Astrophysics Data System (ADS)
Strassmeier, K. G.; Andersen, M. I.; Steinbach, M.
2004-10-01
This paper lays out a wide-field robotic Schmidt telescope (RST) for the Antarctic site Dome C. The telescope is based on 80/120cm reflective Schmidt optics, built originally for a space project, and a mosaic of four 7.5k×7.5k 8-μm thinned CCDs from the PEPSI/LBT wafer run. The telescope's total field of view (FOV) would be 5o circular (minimum 3o× 3o square) with a plate scale of 0.7 arcsec per pixel. Limiting magnitude is expected to be V=21.5mag in 60 sec for a field of 9 square degrees.
Asteroid and comet flux in the neighborhood of the earth
NASA Technical Reports Server (NTRS)
Shoemaker, Eugene M.; Shoemaker, Carolyn S.; Wolfe, Ruth F.
1988-01-01
Significant advances in the knowledge and understanding of the flux of large solid objects in the neighborhood of Earth have occurred. The best estimates of the collision rates with Earth of asteroids and comets and the corresponding production of impact craters are presented. Approximately 80 Earth-crossing asteroids were discovered through May 1988. Among 42 new Earth-crossing asteroids found in the last decade, two-thirds were discovered from observations at Palomar Observatory and 15 were discovered or independently detected in dedicated surveys with the Palomar Observatory and 15 were discovered or independently detected in dedicated surveys with the Palomar 46 cm Schmidt. Probabilities of collision with Earth have been calculated for about two-thirds of the known Earth-crossing asteroids. When multiplied by the estimated population of Earth-crossers, this yields an estimated present rate of collision about 65 pct higher than that previously reported. Spectrophotometric data obtained chiefly in the last decade show that the large majority of obvserved Earth-crossers are similar to asteroids found in the inner part of the main belt. The number of discovered Earth-crossing comets is more than 4 times greater than the number of known Earth-crossing asteroids, but reliable data on the sizes of comet nuclei are sparse. The flux of comets almost certainly was highly variable over late geologic time, owing to the random perturbation of the Oort comet cloud by stars in the solar neighborhood.
Review of Literature on Health Effects of Corn Oil and Its Oxidation Products
2011-04-01
the number of dead fetuses.20 In a retrospective comparison of historical teratology study data for vehicle control animals (Sprague-Dawley...Morrissey, R.E.; Richard, E. Teratologic evaluation of corn oil or distilled water administered to CD rats on gestational days 6 through 15...exposure to corn oil. Teratology , The International Journal of Abnormal Development 1983, 27, 411—416. 17. Shipman, P.M.; Schmidt, R.R. Corn oil
2013-08-28
and dispersion whose behavior is relevant to fuel-injection in propulsion devices. The latter investigations were conducted in water that allows...initially sharp scalar gradients in this high Schmidt-number fluid medium ( water : ⁄ ). Generally, such scalar plumes re reported to exhibit... Flowmetering : The Characteristics of Cylindrical Nozzles with Sharp Upstream Edges. Int. J. Heat and Fluid Flow 1(3):123-132. 3. Research personnel
Validity of Integrity Tests for Predicting Drug and Alcohol Abuse
1993-08-31
Wiinkler and Sheridan (1989) found that employees who entered employee assistance programs for treating drug addiction were more likely be absent...August 31, 1993 Final 4. TITLE AND SUBTITLE S. FUNDING NUMBERS Validity of Integrity Tests for Predicting Drug and Alcohol Abuse C No. N00014-92-J...words) This research used psychometric meta-analysis (Hunter & Schmidt, 1990b) to examine the validity of integrity tests for predicting drug and
2015-03-01
Heekeren, Wartenburger, Schmidt, Prehn , Schwintowski, & Villringer 2005; Jones, 1991; Kagan, 2001; Velasuez & Rostankowski, 1985). Our moral foundation...Business Ethics Quarterly, 21(4), 555-578. Heekeren, H. R., Wartenburger, I., Schmidt, H., Prehn , K., Schwintowski, H. P., & Villringer, A. (2005
Clinical Reasoning Skills of Speech and Language Therapy Students
ERIC Educational Resources Information Center
Hoben, Kirsty; Varley, Rosemary; Cox, Richard
2007-01-01
Background: Difficulties experienced by novices in clinical reasoning have been well documented in many professions, especially medicine (Boshuizen and Schmidt 1992, 2000; Elstein, Shulman and Sprafka 1978; Patel and Groen 1986; Rikers, Loyens and Schmidt 2004). These studies have shown that novice clinicians have difficulties with both knowledge…
Golf Instruction. An Application of Schmidt's Generalized Motor Program.
ERIC Educational Resources Information Center
Asbell, Ann C.
1989-01-01
This article describes how application of the generalized motor program, conceptualized by Schmidt, can yield consistent and effective results when teaching students the golf swing. Specific teaching suggestions are given and a brief discussion of the applicability of this program to tennis and swimming is included. (JAH)
A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini)
Caterino, Michael S.; Tishechkin, Alexey K.
2013-01-01
Abstract We revise the large Neotropical genus Operclipygus Marseul, in the histerid tribe Exosternini (Histeridae: Histerinae). We synonymize 3 species, move 14 species from other genera, sink the genus Tribalister Horn into Operclipygus, and describe 138 species as new, bringing the total to 177 species of Operclipygus. Keys are provided for the identification of all species, and the majority of the species are illustrated by habitus and male genitalia illustrations. The species are diverse throughout tropical South and Central America, with only a few species extending into the temperate parts of North America. The majority of species can be recognized by the presence of a distinct stria or sulcus along the apical margin of the pygidium, though it is not exclusive to the genus. Natural history details for species of Operclipygus are scant, as most specimens have been collected through the use of passive flight interception traps. Many are probably generally associated with decaying vegetation and leaf litter, where they prey on small arthropods. But a small proportion are known inquilines, with social insects such as ants and termites, and also with some burrowing mammals, such as Ctenomys Blainville. The genus now includes the following species groups and species: Operclipygus sulcistrius group [Operclipygus lucanoides sp. n., Operclipygus schmidti sp. n., Operclipygus simplistrius sp. n., Operclipygus sulcistrius Marseul, 1870], Operclipygus mirabilis group [Operclipygus mirabilis (Wenzel & Dybas, 1941) comb. n., Operclipygus pustulifer sp. n., Operclipygus plaumanni sp. n., Operclipygus sinuatus sp. n., Operclipygus mutuca sp. n., Operclipygus carinistrius (Lewis, 1908) comb. n., Operclipygus parensis sp. n., Operclipygus schlingeri sp. n.], Operclipygus kerga group [Operclipygus kerga (Marseul, 1870), Operclipygus planifrons sp. n., Operclipygus punctistrius sp. n.], Operclipygus conquisitus group [Operclipygus bicolor sp. n., Operclipygus conquisitus (Lewis, 1902), Operclipygus friburgius (Marseul, 1864)], Operclipygus impuncticollis group [Operclipygus bickhardti sp. n., Operclipygus britannicus sp. n., Operclipygus impuncticollis (Hinton, 1935)], Operclipygus panamensis group [Operclipygus crenatus (Lewis, 1888), Operclipygus panamensis (Wenzel & Dybas, 1941)], Operclipygus sejunctus group [Operclipygus depressus (Hinton, 1935), Operclipygus itoupe sp. n., Operclipygus juninensis sp. n., Operclipygus pecki sp. n., Operclipygus punctiventer sp. n., Operclipygus sejunctus (Schmidt, 1896) comb. n., Operclipygus setiventrissp. n.], Operclipygus mortavis group [Operclipygus ecitonis sp. n., Operclipygus mortavis sp. n., Operclipygus paraguensis sp. n.], Operclipygus dytiscoides group [Operclipygus carinisternus sp. n., Operclipygus crenulatus sp. n., Operclipygus dytiscoides sp. n., Operclipygus quadratus sp. n.], Operclipygus dubitabilis group [Operclipygus dubitabilis (Marseul, 1889), Operclipygus yasuni sp. n.], Operclipygus angulifer group [Operclipygus angulifer sp. n., Operclipygus impressifrons sp. n.], Operclipygus dubius group [Operclipygus andinus sp. n., Operclipygus dubius (Lewis, 1888), Operclipygus extraneus sp. n., Operclipygus intermissus sp. n., Operclipygus lunulus sp. n., Operclipygus occultus sp. n., Operclipygus perplexus sp. n., Operclipygus remotus sp. n., Operclipygus validus sp. n., Operclipygus variabilis sp. n.], Operclipygus hospes group [Operclipygus assimilis sp. n., Operclipygus belemensis sp. n., Operclipygus bulbistoma sp. n., Operclipygus callifrons sp. n., Operclipygus colombicus sp. n., Operclipygus communis sp. n., Operclipygus confertus sp. n., Operclipygus confluens sp. n., Operclipygus curtistrius sp. n., Operclipygus diffluens sp. n., Operclipygus fusistrius sp. n., Operclipygus gratus sp. n., Operclipygus hospes (Lewis, 1902), Operclipygus ibiscus sp. n., Operclipygus ignifer sp. n., Operclipygus impositus sp. n., Operclipygus incisus sp. n., Operclipygus innocuus sp. n., Operclipygus inquilinus sp. n., Operclipygus minutus sp. n., Operclipygus novateutoniae sp. n., Operclipygus praecinctus sp. n., Operclipygus prominens sp. n., Operclipygus rileyi sp. n., Operclipygus subterraneus sp. n., Operclipygus tenuis sp. n., Operclipygus tiputinus sp. n.], Operclipygus farctus group [Operclipygus atlanticus sp. n., Operclipygus bidessois (Marseul, 1889), Operclipygus distinctus (Hinton, 1935), Operclipygus distractus (Schmidt, 1896) comb. n., Operclipygus farctissimus sp. n., Operclipygus farctus (Marseul, 1864), Operclipygus gilli sp. n., Operclipygus impressistrius sp. n., Operclipygus inflatus sp. n., Operclipygus latemarginatus (Bickhardt, 1920) comb. n., Operclipygus petrovi sp. n., Operclipygus plicatus (Hinton, 1935) comb. n., Operclipygus prolixus sp. n., Operclipygus punctifrons sp. n., Operclipygus proximus sp. n., Operclipygus subrufus sp. n.], Operclipygus hirsutipes group [Operclipygus guianensis sp. n., Operclipygus hirsutipes sp. n.], Operclipygus hamistrius group [Operclipygus arquus sp. n., Operclipygus campbelli sp. n., Operclipygus chiapensis sp. n., Operclipygus dybasi sp. n., Operclipygus geometricus (Casey, 1893) comb. n., Operclipygus hamistrius (Schmidt, 1893) comb. n., Operclipygus impressicollis sp. n., Operclipygus intersectus sp. n., Operclipygus montanus sp. n., Operclipygus nubosus sp. n., Operclipygus pichinchensis sp. n., Operclipygus propinquus sp. n., Operclipygus quinquestriatus sp. n., Operclipygus rubidus (Hinton, 1935) comb. n., Operclipygus rufescens sp. n., Operclipygus troglodytes sp. n.], Operclipygus plicicollis group [Operclipygus cephalicus sp. n., Operclipygus longidens sp. n., Operclipygus plicicollis (Schmidt, 1893)], Operclipygus fossipygus group [Operclipygus disconnectus sp. n., Operclipygus fossipygus (Wenzel, 1944), Operclipygus foveipygus (Bickhardt, 1918), Operclipygus fungicolus (Wenzel & Dybas, 1941), Operclipygus gibbulus (Schmidt, 1889) comb. n., Operclipygus olivensis sp. n., Operclipygus simplicipygus sp. n., Operclipygus subdepressus (Schmidt, 1889), Operclipygus therondi (Wenzel, 1976)], Operclipygus impunctipennis group [Operclipygus chamelensis sp. n., Operclipygus foveiventris sp. n., Operclipygus granulipectus sp. n., Operclipygus impunctipennis (Hinton, 1935) comb. n., Operclipygus latifoveatus sp. n., Operclipygus lissipygus sp. n., Operclipygus maesi sp. n., Operclipygus mangiferus sp. n., Operclipygus marginipennis sp. n., Operclipygus nicodemus sp. n., Operclipygus nitidus sp. n., Operclipygus pacificus sp. n., Operclipygus pauperculus sp. n., Operclipygus punctissipygus sp. n., Operclipygus subviridis sp. n., Operclipygus tripartitus sp. n., Operclipygus vorax sp. n.], Operclipygus marginellus group [Operclipygus ashei sp. n., Operclipygus baylessae sp. n., Operclipygus dentatus sp. n., Operclipygus formicatus sp. n., Operclipygus hintoni sp. n., Operclipygus marginellus (J.E. LeConte, 1860) comb. n., Operclipygus orchidophilus sp. n., Operclipygus selvorum sp. n., Operclipygus striatellus (Fall, 1917) comb. n.], incertae sedis: O. teapensis (Marseul, 1853) comb. n., Operclipygus punctulatus sp. n., Operclipygus lama Mazur, 1988, Operclipygus florifaunensis sp. n., Operclipygus bosquesecus sp. n., Operclipygus arnaudi Dégallier, 1982, Operclipygus subsphaericus sp. n., Operclipygus latipygus sp. n., Operclipygus elongatus sp. n., Operclipygus rupicolus sp. n., Operclipygus punctipleurus sp. n., Operclipygus falini sp. n., Operclipygus peregrinus sp. n., Operclipygus brooksi sp. n., Operclipygus profundipygus sp. n., Operclipygus punctatissimus sp. n., Operclipygus cavisternus sp. n., Operclipygus siluriformis sp. n., Operclipygus parallelus sp. n., Operclipygus abbreviatus sp. n., Operclipygus pygidialis (Lewis, 1908), Operclipygus faltistrius sp. n., Operclipygus limonensis sp. n., Operclipygus wenzeli sp. n., Operclipygus iheringi (Bickhardt, 1917), Operclipygus angustisternus (Wenzel, 1944), Operclipygus shorti sp. n. We establish the following synonymies: Phelisteroides miladae Wenzel & Dybas, 1941 and Pseudister propygidialis Hinton, 1935e = Operclipygus crenatus (Lewis, 1888); Phelister subplicatus Schmidt, 1893b = Operclipygus bidessois (Marseul, 1889). We designate lectotypes for Operclipygus sulcistrius Marseul, 1870, Phelister carinistrius Lewis, 1908, Phelister kerga Marseul, 1870, Phelister friburgius Marseul, 1864, Phelister impuncticollis Hinton, 1935, Phelister crenatus Lewis, 1888, Phelister sejunctus Schmidt, 1896, Pseudister depressus Hinton, 1935, Epierus dubius Lewis, 1888, Phelister hospes Lewis, 1902, Phelister farctus Marseul, 1864, Phelister bidessois Marseul, 1889, Phelister subplicatus Schmidt, 1893, Phelister plicatus Hinton, 1935, Phelister distinctus Hinton, 1935, Phelister distractus Schmidt, 1896, Pseudister latemarginatus Bickhardt, 1920, Phelister hamistrius Schmidt, 1893, Phelister plicicollis Schmidt, 1893, Phelister gibbulus Schmidt, 1889, Phelister subdepressus Schmidt, 1889, Phelister teapensis Marseul, 1853, Phelister pygidialis Lewis, 1908, Phelister iheringi Bickhardt, 1917, and Phelister marginellus J.E. LeConte 1860. We designate a neotype for Operclipygus conquisitus Lewis, replacing its lost type specimen. PMID:23717185
Catching Carbon Stars in the Baade's Windows
NASA Astrophysics Data System (ADS)
Azzopardi, M.; Lequeux, J.; Rebeirot, E.
1984-12-01
Near-infrared objective prism surveys at low dispersion (1 700 to 3400 Amm-1) using Schmidt telescopes have been extensively used to detect M-, S- and C-type stars in the galactic equatorial zone, and in other strategically selected regions of the Milky Way. The detection techniques have been perfected by Nassau and his associates (Nassau and Velghe, 1964, Astrophysical Journal 139, 190) during their survey, at Cleveland, of the northern part of the Milky Way. These techniques are based on the identification of a number of typical molecular bands (TiO, CN, LaO, Va) that fall in the 6800-8800 Aspectral range, and which are used to classify M-, S- and C-type stars (Mavridis, 1967, Coll. on Late Type Stars, p. 420). Using the same method, partial or entire nearinfrared surveys of the southern Milky Way have been carried out by Blanco and Münch (1955, Bol. Obs. Tonantzintla y Tacubaya 12, 273) at Tonantzintla, Smith and Smith (1956, Astronomical Journal 61, 273) at Bloemfontein, and later by Westerlund (1971, Astronomy and Astrophysics Suppl. 4, 51 ; 1978, ibid. 32, 401) with the Uppsala Schmidt telescope at Mount Stromlo Observatory.
Probing the Rate-Determining Step of the Claisen-Schmidt Condensation by Competition Reactions
ERIC Educational Resources Information Center
Mak, Kendrew K. W.; Chan, Wing-Fat; Lung, Ka-Ying; Lam, Wai-Yee; Ng, Weng-Cheong; Lee, Siu-Fung
2007-01-01
Competition experiments are a useful tool for preliminary study of the linear free energy relationship of organic reactions. This article describes a physical organic experiment for upper-level undergraduates to identify the rate-determining step of the Claisen-Schmidt condensation of benzaldehyde and acetophenone by studying the linear free…
ERIC Educational Resources Information Center
Regional Educational Laboratory Mid-Atlantic, 2015
2015-01-01
In this webinar, Dr. William Schmidt of Michigan State University discussed helpful instructional tools for promoting the higher order conceptual thinking found in the Common Core Standards. The PowerPoint presentation and webinar recording are also available.
Listening Journals for Extensive and Intensive Listening Practice
ERIC Educational Resources Information Center
Schmidt, Anthony
2016-01-01
In this article, Anthony Schmidt presents results from his research on listening instruction in a second language. Schmidt reveals that throughout the history of English language teaching (ELT), most students have never been taught how to listen. It was not just listening, but the need to do this listening in conjunction with an approach that…
Passive scalar transport to and from the surface of a Pocillopora coral colony
NASA Astrophysics Data System (ADS)
Hossain, Md Monir; Staples, Anne
2016-11-01
Three-dimensional simulations of flow through a single Pocillopora coral colony were performed to examine the interaction between the flow conditions and scalar transport near a coral colony. With corals currently undergoing a third global bleaching event, a fuller understanding of the transport of nutrients, weak temperature gradients, and other passive scalars to and from the coral polyp tissue is more important than ever. The complex geometry of a coral colony poses a significant challenge for numerical simulation. To simplify grid generation and minimize computational cost, the immersed boundary method was implemented. Large eddy simulation was chosen as the framework to capture the turbulent flow field in the range of realistic Reynolds numbers of 5,000 to 30,000 and turbulent Schmidt numbers of up to 1,000. Both uniform and oscillatory flows through the colony were investigated. Significant differences were found between the cases when the scalar originated at the edge of the flow domain and was transported into the colony, versus when the scalar originated on the surface of the colony and was transported away from the coral. The domain-to-colony transport rates were found to be orders of magnitude higher than the colony-to-domain rates.
Simultaneous PIV and PLIF measurement of passive scalar mixing in a confined planar jet
NASA Astrophysics Data System (ADS)
Feng, Hua
2005-11-01
Simultaneous velocity and concentration fields in a confined liquid-phase planar jet with a Reynolds number based on hydraulic diameter of 50,000 were obtained using combined particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF). Data at six downstream locations were analyzed for flow statistics such as mean velocity, Reynolds stresses, turbulent kinetic energy, concentration mean and variance, turbulent fluxes, turbulent viscosity and diffusivity, and turbulent Schmidt number. Spatial correlation fields of turbulent fluxes and concentration were then determined. The Ru'φ' correlation was elliptical in shape with a major axis tilted downward with respect to the streamwise axis, whereas the Rv'φ' correlation was a horizontally oriented ellipse. The Rφ'φ' correlation field was found to be an ellipse with the major axis inclined at about 45-degrees with respect to the streamwise direction. Linear stochastic estimation was used to determine conditional flow structures. Large-scale structures were observed in the conditional velocity fields that are elliptical in shape with a streamwise major axis. The size of the structure initially increased linearly with respect to downstream distance, but then grew more slowly as the flow evolved towards channel flow.
Distinguishability of generic quantum states
NASA Astrophysics Data System (ADS)
Puchała, Zbigniew; Pawela, Łukasz; Życzkowski, Karol
2016-06-01
Properties of random mixed states of dimension N distributed uniformly with respect to the Hilbert-Schmidt measure are investigated. We show that for large N , due to the concentration of measure, the trace distance between two random states tends to a fixed number D ˜=1 /4 +1 /π , which yields the Helstrom bound on their distinguishability. To arrive at this result, we apply free random calculus and derive the symmetrized Marchenko-Pastur distribution, which is shown to describe numerical data for the model of coupled quantum kicked tops. Asymptotic value for the root fidelity between two random states, √{F }=3/4 , can serve as a universal reference value for further theoretical and experimental studies. Analogous results for quantum relative entropy and Chernoff quantity provide other bounds on the distinguishablity of both states in a multiple measurement setup due to the quantum Sanov theorem. We study also mean entropy of coherence of random pure and mixed states and entanglement of a generic mixed state of a bipartite system.
The discovery and orbit of /2060/ Chiron
NASA Technical Reports Server (NTRS)
Kowal, C. T.; Liller, W.; Marsden, B. G.
1979-01-01
'Slow-moving Object Kowal' was discovered as an asteroidal object of photographic magnitude about 18 on photographic plates made on October 18 and 19, 1977 with the 122-cm Schmidt telescope at Palomar Observatory. It was determined that the object was located between 14 and 17 AU from the earth in a low-inclination, near-circular orbit. Examination of subsequent plates and earlier observations of the area allowed a more exact calculation of the orbital elements, which suggest the object to be in 3:5 resonance with Saturn at a perihelion of 8.5 AU. The object's orbital behavior suggests that of an inactive comet perturbed by Saturn from a previous orbit, however its magnitude is uncharacteristically large for a comet. It is proposed that object Kowal was once an ordinary minor planet that was deflected into its present orbit by collisions with other minor planets and a series of encounters with Jupiter and Saturn. The object has received the minor planet number (2060) and the name of Chiron has been proposed.
A random distribution reacting mixing layer model
NASA Technical Reports Server (NTRS)
Jones, Richard A.; Marek, C. John; Myrabo, Leik N.; Nagamatsu, Henry T.
1994-01-01
A methodology for simulation of molecular mixing, and the resulting velocity and temperature fields has been developed. The ideas are applied to the flow conditions present in the NASA Lewis Research Center Planar Reacting Shear Layer (PRSL) facility, and results compared to experimental data. A gaussian transverse turbulent velocity distribution is used in conjunction with a linearly increasing time scale to describe the mixing of different regions of the flow. Equilibrium reaction calculations are then performed on the mix to arrive at a new species composition and temperature. Velocities are determined through summation of momentum contributions. The analysis indicates a combustion efficiency of the order of 80 percent for the reacting mixing layer, and a turbulent Schmidt number of 2/3. The success of the model is attributed to the simulation of large-scale transport of fluid. The favorable comparison shows that a relatively quick and simple PC calculation is capable of simulating the basic flow structure in the reacting and nonreacting shear layer present in the facility given basic assumptions about turbulence properties.
Stability of miscible core?annular flows with viscosity stratification
NASA Astrophysics Data System (ADS)
Selvam, B.; Merk, S.; Govindarajan, Rama; Meiburg, E.
The linear stability of variable viscosity, miscible core-annular flows is investigated. Consistent with pipe flow of a single fluid, the flow is stable at any Reynolds number when the magnitude of the viscosity ratio is less than a critical value. This is in contrast to the immiscible case without interfacial tension, which is unstable at any viscosity ratio. Beyond the critical value of the viscosity ratio, the flow can be unstable even when the more viscous fluid is in the core. This is in contrast to plane channel flows with finite interface thickness, which are always stabilized relative to single fluid flow when the less viscous fluid is in contact with the wall. If the more viscous fluid occupies the core, the axisymmetric mode usually dominates over the corkscrew mode. It is demonstrated that, for a less viscous core, the corkscrew mode is inviscidly unstable, whereas the axisymmetric mode is unstable for small Reynolds numbers at high Schmidt numbers. For the parameters under consideration, the switchover occurs at an intermediate Schmidt number of about 500. The occurrence of inviscid instability for the corkscrew mode is shown to be consistent with the Rayleigh criterion for pipe flows. In some parameter ranges, the miscible flow is seen to be more unstable than its immiscible counterpart, and the physical reasons for this behaviour are discussed.A detailed parametric study shows that increasing the interface thickness has a uniformly stabilizing effect. The flow is least stable when the interface between the two fluids is located at approximately 0.6 times the tube radius. Unlike for channel flow, there is no sudden change in the stability with radial location of the interface. The instability originates mainly in the less viscous fluid, close to the interface.
The Potential Neurotoxic Effects of Low-Dose Sarin Exposure in a Guinea Pig Model
2002-01-01
1 THE POTENTIAL NEUROTOXIC EFFECTS OF LOW-DOSE SARIN EXPOSURE IN A GUINEA PIG MODEL Melinda R. Roberson, PhD, Michelle B. Schmidt...Proving Ground, MD 21010 USA ABSTRACT This study is assessing the effects in guinea pigs of repeated low-dose exposure to the nerve...COVERED - 4. TITLE AND SUBTITLE The Potential Neurotoxic Effects Of Low-Dose Sarin Exposure In A Guinea Pig Model 5a. CONTRACT NUMBER 5b
Nanofluid slip flow over a stretching cylinder with Schmidt and Péclet number effects
NASA Astrophysics Data System (ADS)
Md Basir, Md Faisal; Uddin, M. J.; Md. Ismail, A. I.; Bég, O. Anwar
2016-05-01
A mathematical model is presented for three-dimensional unsteady boundary layer slip flow of Newtonian nanofluids containing gyrotactic microorganisms over a stretching cylinder. Both hydrodynamic and thermal slips are included. By applying suitable similarity transformations, the governing equations are transformed into a set of nonlinear ordinary differential equations with appropriate boundary conditions. The transformed nonlinear ordinary differential boundary value problem is then solved using the Runge-Kutta-Fehlberg fourth-fifth order numerical method in Maple 18 symbolic software. The effects of the controlling parameters on the dimensionless velocity, temperature, nanoparticle volume fractions and microorganism motile density functions have been illustrated graphically. Comparisons of the present paper with the existing published results indicate good agreement and supports the validity and the accuracy of our numerical computations. Increasing bioconvection Schmidt number is observed to depress motile micro-organism density function. Increasing thermal slip parameter leads to a decrease in temperature. Thermal slip also exerts a strong influence on nano-particle concentration. The flow is accelerated with positive unsteadiness parameter (accelerating cylinder) and temperature and micro-organism density function are also increased. However nano-particle concentration is reduced with positive unsteadiness parameter. Increasing hydrodynamic slip is observed to boost temperatures and micro-organism density whereas it decelerates the flow and reduces nano-particle concentrations. The study is relevant to nano-biopolymer manufacturing processes.
Optical design of the SuMIRe/PFS spectrograph
NASA Astrophysics Data System (ADS)
Pascal, Sandrine; Vives, Sébastien; Barkhouser, Robert; Gunn, James E.
2014-07-01
The SuMIRe Prime Focus Spectrograph (PFS), developed for the 8-m class SUBARU telescope, will consist of four identical spectrographs, each receiving 600 fibers from a 2394 fiber robotic positioner at the telescope prime focus. Each spectrograph includes three spectral channels to cover the wavelength range [0.38-1.26] um with a resolving power ranging between 2000 and 4000. A medium resolution mode is also implemented to reach a resolving power of 5000 at 0.8 um. Each spectrograph is made of 4 optical units: the entrance unit which produces three corrected collimated beams and three camera units (one per spectral channel: "blue, "red", and "NIR"). The beam is split by using two large dichroics; and in each arm, the light is dispersed by large VPH gratings (about 280x280mm). The proposed optical design was optimized to achieve the requested image quality while simplifying the manufacturing of the whole optical system. The camera design consists in an innovative Schmidt camera observing a large field-of-view (10 degrees) with a very fast beam (F/1.09). To achieve such a performance, the classical spherical mirror is replaced by a catadioptric mirror (i.e meniscus lens with a reflective surface on the rear side of the glass, like a Mangin mirror). This article focuses on the optical architecture of the PFS spectrograph and the perfornance achieved. We will first described the global optical design of the spectrograph. Then, we will focus on the Mangin-Schmidt camera design. The analysis of the optical performance and the results obtained are presented in the last section.
Support system design of the sub-mirror cell of the LAMOST Schmidt plate
NASA Astrophysics Data System (ADS)
Yang, Dehua; Jiang, Fanghua
2006-06-01
The reflecting Schmidt plate of the Large sky Area Multi-Object Spectroscopic Telescope (LAMOST) is composed of 24 hexagonal segments, each of which is 1100 mm from corner to corner and 25 mm in thickness. Both segmented mirror active optics and deformable mirror active optics are involved in the Schmidt plate so as to compensate for optical aberration and structural deformation. A prototype of the segment support system with dummy aluminum mirror had been setup and tested during 2003 to 2004, afterwards, based on the evaluation of test, the whole support system was updated to a backlash-free and light-weighted design. For the segmented mirror active optics, the segment mirror support system is to fulfill motions of tip, tilt and piston with three linear positioning actuators. Instead of self-alignment bearing adopted in the early prototype, a centering diaphragm is employed to realize a backlash-free pintle. And a lever with reduction of 10:1 is introduced to each of the three positioning actuator mechanisms, respectively, to obtain greater load capacity and further finer output displacement, as hence releases requirement and cost of the actuators. For better performance, high strength steel blades are used in tension state for pivots of the levers preloaded with longitudinal springs. To gap the mirror segments with respect to each other for making proper space for edge sensors, three adjustable fixtures are implemented for each segment mirror module to do translation and pistion on three conrresponding nodes on the top layer of the gross mirror cell truss before being anchored once and forever. In addition, safety measurements as well as anti-rotation mechanism have been taken into consideration throughout the design and development process. This paper describes the mechanical design and related analysis of the segment mirror support system in detail.
NASA Astrophysics Data System (ADS)
Winkler, Stefan; Lambiel, Christophe; Sattler, Katrin; Büche, Thomas; Springer, Johanna
2016-04-01
Although not uncommon within the dryer eastern parts of the Southern Alps, New Zealand, comparatively few previous studies have previously focused on rock glacier dynamics and spatial distribution. Neither investigations of their chronological constraints nor any studies on actual rock glacier velocities have yet been carried out. Rock glaciers and periglacial processes still largely constitute a largely unexplored albeit potentially valuable field of research in the Southern Alps. The high-altitude valley head of Irishman Stream in the Ben Ohau Range between Lakes Ohau and Pukaki, roughly 30 km southeast of the Main Divide, contains a few morphologically intact rock glaciers and some appear to be active features (Sattler et al. 2016). Previous work focusing on the Late-glacial and early Holocene moraines in the valley head below the rock glaciers (Kaplan et al. 2010) provided 10Be-ages that could be utilised as fixed points for SHD (Schmidt-hammer exposure-age dating). Apart from detailed Schmidt-hammer sampling on the Late-glacial and early Holocene moraines, two altitudinal transects from the toe to their apex have been measured in detail on selected rock glaciers. On each of the multiple ridges of the rock glacier surface three sites of 50 boulders have been sampled with one impact each by the hammer (an N-type electronic SilverSchmidt by Proceq). Apart from getting some age constraints of these periglacial features in comparison to the well-dated moraines, the Schmidt-hammer measurements also had the aim to provide some insight into their genetic development resulting in a quite complex morphology of the rock glaciers and partial interaction with some of the moraines. Both altitudinal transects reveal a clear and continuous trend of increasing means (i.e. less weathered/younger exposure ages) towards their apex. The values for the individual ridges show, however, a transitional character with adjacent ridges albeit the abovementioned trend not statistically significant different in age, a phenomena known from similar studies on rock glaciers elsewhere. Already during sampling it became obvious that with increasing altitude and decreasing distance to the valley headwall the percentage of freshly appearing boulders vs. weathered boulders with a distinct micro-relief is getting higher. The means of the lowermost ridges of the rock glaciers show, however, no significant difference to the early Holocene moraines dated to c. 11.5 10Be ka ago. This may indicate that rock glacier formation initiated shortly after Termination 1 during the early Holocene and partly overrode some parts of the early Holocene moraines. During the field work, a network of 46 differential GPS points has been established to start future monitoring of any potential rock glacier movement. It will allow exploring the climatological control on rock glacier behaviour in in the Southern Alps, as well as comparisons with current velocities measured in the European Alps. References: Kaplan, M.R., Schaefer, J., Denton, G.H., Barrell, D.J.A., Chinn, T.J.H., Putnam, A.E., Anderson, B.G., Finkel, R.C., Schwartz, R. & Doughty, A.M. (2010): Glacier retreat in New Zealand during the Younger DryasStadial. Nature 467, 194-197. Sattler, K., Anderson, B., Mackintosh, A., Norton, K., de Róiste, M. (2016): Estimating permafrost distribution in the maritime SouthernAlps, New Zealand, based on climatic conditions at rock glacier sites. Frontiers in Earth Science - Section Cryospheric Sciences. doi: 10.3389/feart.2016.00004.
NASA Astrophysics Data System (ADS)
de Jong, Rixt; Kamenik, Christian; Grosjean, Martin
2010-05-01
To fully understand past climatic changes and their forcing factors, detailed reconstructions of past summer and winter temperatures are required. Winter temperature reconstructions are scarce, however, because most biological proxies are biased towards the growing season. This study presents a detailed reconstruction of winter temperatures based on Chrysophyte stomatocysts, silicious scales formed by so-called 'golden algae'. Previous studies (Kamenik and Schmidt, 2005; Pla and Catalan, 2005) have demonstrated the sensitivity of these algae to cold-season temperatures. Chrysophyte stomatocyst analysis was carried out on varved sediments from Lake Silvaplana (1791 m a.s.l.) at annual to near-annual resolution for two periods; AD 1100-1500 and AD 1870-2004. For both periods the reference date 'date of spring mixing' (Smix) was reconstructed using a transfer function developed for the Austrian Alps (Kamenik and Schmidt, 2005). In the Austrian Alps, Smix was primarily driven by air temperature in the cold season. The strength of stomatocysts as a proxy for winter temperature was tested by directly comparing reconstructed Smix with measured temperatures from nearby meteostation Sils Maria for the period AD 1870 - 2004. Correlation was highest (R = -0.6; p < 0.001) with mean October-April temperatures. The good agreement between reconstructed Smix and mean winter temperatures was interrupted only from AD 1925 - AD 1951, which was related to exceptionally high winter precipitation (thick snowpack) extending the ice-covered period. Strong lake eutrophication after AD 1950 only weakly affected the reconstruction of winter temperature. The winter temperature reconstruction (AD 1100-1500) shows strong interdecadal variability, superimposed on a cooling trend from around AD 1400 onwards. A direct comparison to summer temperature reconstructions based on biogenic silica and chironomid analysis from the same cores (Trachsel et al., in review; Larocque-Tobler et al., accepted manuscript) indicated strong fluctuations in intra-annual variability. A comparison to forcing factors shows that throughout the studied period, large tropical volcanic eruptions (Crowley, 2000) coincided with relatively warm winters in the study area. This is consistent with results from GCM experiments and observations of the limited number of eruptions during the much shorter instrumental period (Fischer et al., 2007). References: T. Crowley. Science 289, 270-277 (2000) E. Fischer et al. Geophys. Res. Lett. 34, L05707 (2007) C. Kamenik and R. Schmidt. Boreas 34, 477-489 (2005) I. Larocque-Tobler et al. Quat. Sci. Rev., accepted. S. Pla and J. Catalan. Clim. Dyn. 24, 263-278 (2005) M. Trachsel et al. Manuscript in review
Measurements in a separation bubble on an airfoil using laser velocimetry
NASA Technical Reports Server (NTRS)
Fitzgerald, Edward J.; Mueller, Thomas J.
1990-01-01
An experimental investigation was conducted to measure the reverse flow within the transitional separation bubble that forms on an airfoil at low Reynolds numbers. Measurements were used to determine the effect of the reverse flow on integrated boundary-layer parameters often used to model the bubble. Velocity profile data were obtained on an NACA 663-018 airfoil at angle of attack of 12 deg and a chord Reynolds number of 140,000 using laser Doppler and single-sensor hot-wire anemometry. A new correlation is proposed based on zero velocity position, since the Schmidt (1986) correlations fail in the turbulent portion of the bubble.
Hall effects on hydromagnetic free convection flow along a porous flat plate with mass transfer
NASA Astrophysics Data System (ADS)
Hossain, M. A.; Rashid, R. I. M. A.
1987-01-01
Effect of Hall current on the unsteady free convection flow of a viscous incompressible and electrically conducting fluid, in presence of foreign gases (such as H2, CO2, H2O, NH3), along an infinite vertical porous flat plate subjected to a transpiration velocity inversely proportional to the square-root of time is investigated in the presence of a uniform transverse magnetic field. The results are discussed with the effects of the parameters Gc (the Grashof number for mass transfer), m (the Hall parameter) and Sc (the Schmidt number) for Pr = 0.71, which represents air.
NASA Astrophysics Data System (ADS)
Ganesh Kumar, K.; Rizwan-ul-Haq; Rudraswamy, N. G.; Gireesha, B. J.
The present study addresses the three-dimensional flow of a Prandtl fluid over a Riga plate in the presence of chemical reaction and convective condition. The converted set of boundary layer equations are solved numerically by RKF four-fifth method. Obtained numerical results for flow and mass transfer characteristics are discussed for various physical parameters. Additionally, the skin friction coefficient and Sherwood number are also presented. It is found that, the momentum boundary layer thickness is dominant for higher values of α and solutal boundary layer is low for higher Schmidt number and chemical reaction parameter.
Coltrin, Michael E.; Kee, Robert J.
2016-06-18
This paper develops a unified analysis of stagnation flow heat and mass transport, considering both semi-infinite domains and finite gaps, with and without rotation of the stagnation surface. An important objective is to derive Nusselt- and Sherwood-number correlations that represent heat and mass transport at the stagnation surface. The approach is based on computationally solving the governing conservation equations in similarity form as a boundary-value problem. The formulation considers ideal gases and incompressible fluids. The correlated results depend on fluid properties in terms of Prandtl, Schmidt, and Damkohler numbers. Heterogeneous chemistry at the stagnation surface is represented as a singlemore » first-order reaction. A composite Reynolds number represents the combination of stagnation flows with and without stagnation-surface rotation.« less
NASA Astrophysics Data System (ADS)
Hayat, T.; Ahmad, Salman; Khan, M. Ijaz; Alsaedi, A.; Waqas, M.
2018-06-01
Here we investigated stagnation point flow of second grade fluid over a stretchable cylinder. Heat transfer is characterized by non-Fourier law of heat flux and thermal stratification. Temperature dependent thermal conductivity and activation energy are also accounted. Transformations procedure is applying to transform the governing PDE's into ODE's. Obtained system of ODE's are solved analytically by HAM. Influence of flow variables on velocity, temperature, concentration, skin friction and Sherwood number are analyzed. Obtained outcome shows that velocity enhanced through curvature parameter, viscoelastic parameter and velocities ratio variable. Temperature decays for larger Prandtl number, thermal stratification, thermal relaxation and curvature parameter. Sherwood number and concentration field show opposite behavior for higher estimation of activation energy, reaction rate, curvature parameter and Schmidt number.
NASA Technical Reports Server (NTRS)
Gokoglu, S. A.; Rosner, D. E.
1984-01-01
Modification of the code STAN5 to properly include thermophoretic mass transport, and examination of selected test cases developing boundary layers which include variable properties, viscous dissipation, transition to turbulence and transpiration cooling. Under conditions representative of current and projected GT operation, local application of St(M)/St(M),o correlations evidently provides accurate and economical engineering design predictions, especially for suspended particles characterized by Schmidt numbers outside of the heavy vapor range.
1981-08-01
Absenteeism Behavior from Knowledge of Job Sat- isfaction and Organizational Commitment James R. Terborg Thomas W. Lee Frank J. Smith Gregory A. Davis Mark...GRANT NUMBER() James R. Terborg, Thomas W. Lee, Frank J. Smith, Gregory A. Davis, and Mark S. Turbin. No. 00014-81-K-0406 /1 S. PERFORMING ORGANIZATION...Organizational Commitment Situational Specificity Absenteeism Meta-Analysis •Research would suggest that the relationship between job satisfaction and ab
ERIC Educational Resources Information Center
Hipolito-Delgado, Carlos P.; Lee, Courtland C.
2007-01-01
In this article, the authors provide their reactions to the commentaries of Mitcham-Smith and Schmidt on their study. As Mitcham-Smith and Schmidt in their responses both suggest, it is evident that if professional school counselors are to be successful in facilitating the empowerment of students, they must engage in a self-reflective process…
History and Development of the Schmidt-Hunter Meta-Analysis Methods
ERIC Educational Resources Information Center
Schmidt, Frank L.
2015-01-01
In this article, I provide answers to the questions posed by Will Shadish about the history and development of the Schmidt-Hunter methods of meta-analysis. In the 1970s, I headed a research program on personnel selection at the US Office of Personnel Management (OPM). After our research showed that validity studies have low statistical power, OPM…
NASA Astrophysics Data System (ADS)
Rushi Kumar, B.; Jayakar, R.; Vijay Kumar, A. G.
2017-11-01
An exact analysis of the problem of free convection flow of a viscous incompressible chemically reacting fluid past an infinite vertical plate with the flow due to impulsive motion of the plate with Newtonian heating in the presence of thermal radiation and variable mass diffusion is performed. The resulting governing equations were tackled by Laplace transform technique. Finally the effects of pertinent flow parameters such as the radiation parameter, chemical reaction parameter, buoyancy ratio parameter, thermal Grashof number, Schmidt number, Prandtl number and time on the velocity, temperature, concentration and skin friction for both aiding and opposing flows were examined in detail when Pr=0.71(conducting air) and Pr=7.0(water).
Fermi LAT detection of a continuing increase of gamma-ray activity of CTA 102
NASA Astrophysics Data System (ADS)
Orienti, M.; D'Ammando, F.
2012-09-01
The Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope, has observed gamma-ray flaring activity from a source positionally consistent with the flat spectrum radio quasar CTA 102 (also known as 2FGL J2232.4+1143, Nolan et al. 2012, ApJS, 199, 31) with radio coordinates R.A.: 338.1517038 deg, Dec: 11.7308067 deg (J2000, Johnston et al. 1995, AJ, 110, 880) at redshift z=1.037 (Schmidt 1965, ApJ, 141, 1295).
A numerical study of transient heat and mass transfer in crystal growth
NASA Technical Reports Server (NTRS)
Han, Samuel Bang-Moo
1987-01-01
A numerical analysis of transient heat and solute transport across a rectangular cavity is performed. Five nonlinear partial differential equations which govern the conservation of mass, momentum, energy and solute concentration related to crystal growth in solution, are simultaneously integrated by a numerical method based on the SIMPLE algorithm. Numerical results showed that the flow, temperature and solute fields are dependent on thermal and solutal Grashoff number, Prandtl number, Schmidt number and aspect ratio. The average Nusselt and Sherwood numbers evaluated at the center of the cavity decrease markedly when the solutal buoyancy force acts in the opposite direction to the thermal buoyancy force. When the solutal and thermal buoyancy forces act in the same direction, however, Sherwood number increases significantly and yet Nusselt number decreases. Overall effects of convection on the crystal growth are seen to be an enhancement of growth rate as expected but with highly nonuniform spatial growth variations.
Solar Observations on Magneto-Convection
1989-05-31
Technical Library National Solar Observatory Sunspot, NM 88349 Karl - Schwarzschild -Strasse 1 8046 Garching bei Mundhen Solar Observations On Magneto...Schmidt, Hermann-Ulrich Schmidt, Hans-Christoph Thomas (eds.) Max-Planck-Institut fir Physik und Astrophysik Institut fiur Astrophysik Karl ... Schwarzschild -St-. 1 D-8046 Garching, FklG 14TIS CRiA.&l DTIC TA. U~Jar,iou8:ed B ......... ... Distribution I -- Availability COcý----- Avail and or Dist special
NASA Astrophysics Data System (ADS)
Patil, Vishal; Liburdy, James
2012-11-01
Turbulent porous media flows are encountered in catalytic bed reactors and heat exchangers. Dispersion and mixing properties of these flows play an essential role in efficiency and performance. In an effort to understand these flows, pore scale time resolved PIV measurements in a refractive index matched porous bed were made. Pore Reynolds numbers, based on hydraulic diameter and pore average velocity, were varied from 400-4000. Jet-like flows and recirculation regions associated with large scale structures were found to exist. Coherent vortical structures which convect at approximately 0.8 times the pore average velocity were identified. These different flow regions exhibited different turbulent characteristics and hence contributed unequally to global transport properties of the bed. The heterogeneity present within a pore and also from pore to pore can be accounted for in estimating transport properties using the method of volume averaging. Eddy viscosity maps and mean velocity field maps, both obtained from PIV measurements, along with the method of volume averaging were used to predict the dispersion tensor versus Reynolds number. Asymptotic values of dispersion compare well to existing correlations. The role of molecular diffusion was explored by varying the Schmidt number and molecular diffusion was found to play an important role in tracer transport, especially in recirculation regions. Funding by NSF grant 0933857, Particulate and Multiphase Processing.
Design and realization of the real-time spectrograph controller for LAMOST based on FPGA
NASA Astrophysics Data System (ADS)
Wang, Jianing; Wu, Liyan; Zeng, Yizhong; Dai, Songxin; Hu, Zhongwen; Zhu, Yongtian; Wang, Lei; Wu, Zhen; Chen, Yi
2008-08-01
A large Schmitt reflector telescope, Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST), is being built in China, which has effective aperture of 4 meters and can observe the spectra of as many as 4000 objects simultaneously. To fit such a large amount of observational objects, the dispersion part is composed of a set of 16 multipurpose fiber-fed double-beam Schmidt spectrographs, of which each has about ten of moveable components realtimely accommodated and manipulated by a controller. An industrial Ethernet network connects those 16 spectrograph controllers. The light from stars is fed to the entrance slits of the spectrographs with optical fibers. In this paper, we mainly introduce the design and realization of our real-time controller for the spectrograph, our design using the technique of System On Programmable Chip (SOPC) based on Field Programmable Gate Array (FPGA) and then realizing the control of the spectrographs through NIOSII Soft Core Embedded Processor. We seal the stepper motor controller as intellectual property (IP) cores and reuse it, greatly simplifying the design process and then shortening the development time. Under the embedded operating system μC/OS-II, a multi-tasks control program has been well written to realize the real-time control of the moveable parts of the spectrographs. At present, a number of such controllers have been applied in the spectrograph of LAMOST.
Controls on gas transfer velocities in a large river
NASA Astrophysics Data System (ADS)
Beaulieu, Jake J.; Shuster, William D.; Rebholz, Jacob A.
2012-06-01
The emission of biogenic gases from large rivers can be an important component of regional greenhouse gas budgets. However, emission rate estimates are often poorly constrained due to uncertainties in the air-water gas exchange rate. We used the floating chamber method to estimate the gas transfer velocity (k) of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in the Markland Pool of the Ohio River, a large tributary of the Mississippi River (U.S.A). We measured k every two weeks for a year at one site and at 15 additional sites distributed across the length of the pool during two summer surveys. We found that k was positively related to both water currents and wind speeds, with 46% of the gas transfer attributable to water currents at low wind speeds (e.g., 0.5 m s-1) and 11% at higher wind speeds (e.g., >2.0 m s-1). Gas transfer velocity was highly sensitive to wind, possibly because the direction of river flow was often directly opposed to the wind direction. Gas transfer velocity values derived for CH4 were consistently greater than those derived for CO2 when standardized to a Schmidt number of 600 (k600), possibly because the transfer of CH4, a poorly soluble gas, was enhanced by surfacing microbubbles. Additional research to determine the conditions that support microbubble enhanced gas transfer is merited.
Schmidt, J A; Olsen, J M H
2014-11-14
The photodissociation of carbonyl sulfide (OCS) was investigated theoretically in a series of studies by Schmidt and co-workers. Initial studies [J. A. Schmidt, M. S. Johnson, G. C. McBane, and R. Schinke, J. Chem. Phys. 136, 131101 (2012); J. A. Schmidt, M. S. Johnson, G. C. McBane, and R. Schinke, J. Chem. Phys. 137, 054313 (2012)] found photodissociation in the first UV-band to occur mainly by excitation of the 2(1)A' (A) excited state. However, in a later study [G. C. McBane, J. A. Schmidt, M. S. Johnson, and R. Schinke, J. Chem. Phys. 138, 094314 (2013)] it was found that a significant fraction of photodissociation must occur by excitation of 1(1)A″ (B) excited state to explain the product angular distribution. The branching between excitation of the A and B excited states is determined by the magnitude of the transition dipole moment vectors in the Franck-Condon region. This study examines the sensitivity of these quantities to changes in the employed electronic structure methodology. This study benchmarks the methodology employed in previous studies against highly correlated electronic structure methods (CC3 and MRAQCC) and provide evidence in support of the picture of the OCS photodissociation process presented in [G. C. McBane, J. A. Schmidt, M. S. Johnson, and R. Schinke, J. Chem. Phys. 138, 094314 (2013)] showing that excitation of A and B electronic states both contribute significantly to the first UV absorption band of OCS. In addition, this study presents evidence in support of the assertion that the A state potential energy surface employed in previous studies underestimates the energy at highly bent geometries (γ ∼ 70°) leading to overestimated rotational energy in the product CO.
NASA Astrophysics Data System (ADS)
Clay, M. P.; Buaria, D.; Yeung, P. K.; Gotoh, T.
2018-07-01
This paper reports on the successful implementation of a massively parallel GPU-accelerated algorithm for the direct numerical simulation of turbulent mixing at high Schmidt number. The work stems from a recent development (Comput. Phys. Commun., vol. 219, 2017, 313-328), in which a low-communication algorithm was shown to attain high degrees of scalability on the Cray XE6 architecture when overlapping communication and computation via dedicated communication threads. An even higher level of performance has now been achieved using OpenMP 4.5 on the Cray XK7 architecture, where on each node the 16 integer cores of an AMD Interlagos processor share a single Nvidia K20X GPU accelerator. In the new algorithm, data movements are minimized by performing virtually all of the intensive scalar field computations in the form of combined compact finite difference (CCD) operations on the GPUs. A memory layout in departure from usual practices is found to provide much better performance for a specific kernel required to apply the CCD scheme. Asynchronous execution enabled by adding the OpenMP 4.5 NOWAIT clause to TARGET constructs improves scalability when used to overlap computation on the GPUs with computation and communication on the CPUs. On the 27-petaflops supercomputer Titan at Oak Ridge National Laboratory, USA, a GPU-to-CPU speedup factor of approximately 5 is consistently observed at the largest problem size of 81923 grid points for the scalar field computed with 8192 XK7 nodes.
Elastica solution for a nanotube formed by self-adhesion of a folded thin film
NASA Astrophysics Data System (ADS)
Glassmaker, N. J.; Hui, C. Y.
2004-09-01
Schmidt and Eberl demonstrated the construction of tubes with submicron diameters by the method of folding thin solid films [Nature (London) 410, 168 (2001)]. In their method, a thin film is folded 180° and brought into adhesive contact with itself. The resulting sealed loop forms a nanotube with the thickness of the tube walls equal to the thickness of the thin film. The calculation of the diameter of the tube and the shape of its cross section in equilibrium are the subjects of this study. The tube is modeled as a two-dimensional elastica when viewed in cross section, and adhesive behavior is governed by an energy release rate criterion. A numerical technique is used to find elastic equilibria for a large range of material parameters. With these solutions in hand, the problem of designing a nanotube becomes transparent. It is shown that one dimensionless parameter determines the diameter of the nanotube, while another fixes its shape. Each of these parameters is a ratio involving the material's mechanical properties and the film thickness. Before concluding, we verify our model by comparing its results with the experimental observations of Schmidt and Eberl, for their materials.
Divergent Synthesis of Solanidine and 22-epi-Solanidine.
Hou, Ling-Li; Shi, Yong; Zhang, Zhi-Dan; Wu, Jing-Jing; Yang, Qing-Xiong; Tian, Wei-Sheng
2017-07-21
A divergent synthesis of solanidine and 22-epi-solanidine, two 25S natural steroidal alkaloids, from 25R-configured diosgenin acetate, is described. Initially, solanidine was synthesized through a series of transformations including a cascade ring-switching process of furostan-26-acid, an epimerization of C25 controlled by the conformation of six-membered lactone ring, an intramolecular Schmidt reaction, and an imine reduction/intramolecular aminolysis process. To address the epimerization issue during Schmidt reaction, an improved synthesis was developed, which also led to a synthesis of 22-epi-solanidine. In this synthesis, selective transformation of azido lactone to azido diol and amino diol was realized through a reduction relay tactic. The azido diol was transformed to solanidine via an intramolecular Schmidt reaction/N-alkylation/reduction process and to 22-epi-solanidine via an intramolecular double N-alkylation process.
Thermally developed peristaltic propulsion of magnetic solid particles in biorheological fluids
NASA Astrophysics Data System (ADS)
Bhatti, M. M.; Zeeshan, A.; Tripathi, D.; Ellahi, R.
2018-04-01
In this article, effects of heat and mass transfer on MHD peristaltic motion of solid particles in a dusty fluid are investigated. The effects of nonlinear thermal radiation and Hall current are also taken into account. The relevant flow analysis is modelled for fluid phase and dust phase in wave frame by means of Casson fluid model. Computation of solutions is presented for velocity profile, temperature profile and concentration profile. The effects of all the physical parameters such as particle volume fraction, Hartmann number, Hall Effect, Prandtl number, Eckert number, Schmidt number and Soret number are discussed mathematically and graphically. It is noted that the influence of magnetic field and particle volume fraction opposes the flow. Also, the impact of particle volume fraction is quite opposite on temperature and concentration profile. This model is applicable in smart drug delivery systems and bacteria movement in urine flow through the ureter.
Hayat, Tasawar; Qayyum, Sajid; Alsaedi, Ahmed; Asghar, Saleem
2017-01-01
This study investigates the mixed convection flow of Jeffrey liquid by an impermeable inclined stretching cylinder. Thermal radiation and non-uniform heat source/sink are considered. The convective boundary conditions at surface are imposed. Nonlinear expressions of momentum, energy and concentration are transformed into dimensionless systems. Convergent homotopic solutions of the governing systems are worked out by employing homotopic procedure. Impact of physical variables on the velocity, temperature and concentration distributions are sketched and discussed. Numerical computations for skin friction coefficient, local Nusselt and Sherwood numbers are carried out. It is concluded that velocity field enhances for Deborah number while reverse situation is observed regarding ratio of relaxation to retardation times. Temperature and heat transfer rate are enhanced via larger thermal Biot number. Effect of Schmidt number on the concentration and local Sherwood number is quite reverse.
Hayat, Tasawar; Qayyum, Sajid; Alsaedi, Ahmed; Asghar, Saleem
2017-01-01
This study investigates the mixed convection flow of Jeffrey liquid by an impermeable inclined stretching cylinder. Thermal radiation and non-uniform heat source/sink are considered. The convective boundary conditions at surface are imposed. Nonlinear expressions of momentum, energy and concentration are transformed into dimensionless systems. Convergent homotopic solutions of the governing systems are worked out by employing homotopic procedure. Impact of physical variables on the velocity, temperature and concentration distributions are sketched and discussed. Numerical computations for skin friction coefficient, local Nusselt and Sherwood numbers are carried out. It is concluded that velocity field enhances for Deborah number while reverse situation is observed regarding ratio of relaxation to retardation times. Temperature and heat transfer rate are enhanced via larger thermal Biot number. Effect of Schmidt number on the concentration and local Sherwood number is quite reverse. PMID:28441392
Optimizing Feedback Utilization in Motor Skill Training
1988-02-01
Abehiorlemphasis. Champaign, IL: Human Kinetics Press. Schmidt, R.A., & White, J.L. (1972). Evidence for an error-detection mechanism in motor skills...motor program. In D.M. Landers & R.W. Christina (Eds.), Psyc g 2 moto behavior d S (Vol 1). Champaign, IL: Human Kinetics Press. Shapiro, D.C. (1978...and sport research. Champaign, IL: Human Kinetics Press. Schmidt, R.A. (in press). Toward a better understanding of motor learning. Theoretical and
Quantum teleportation via quantum channels with non-maximal Schmidt rank
NASA Astrophysics Data System (ADS)
Solís-Prosser, M. A.; Jiménez, O.; Neves, L.; Delgado, A.
2013-03-01
We study the problem of teleporting unknown pure states of a single qudit via a pure quantum channel with non-maximal Schmidt rank. We relate this process to the discrimination of linearly dependent symmetric states with the help of the maximum-confidence discrimination strategy. We show that with a certain probability, it is possible to teleport with a fidelity larger than the fidelity optimal deterministic teleportation.
Analyzing Divisia Rules Extracted from a Feedforward Neural Network
2006-03-01
assumptions. (Barnett and work, Data Mining, Rule Generation Serletis give a detailed treatment of the the- ory of monetary aggregation [1].) However, 1... Serletis , A. (Eds.) (2000), The The- Swizerland, 1995. ory of Monetary Aggregation, North-H ollandeAmsterdam, Chgaptero , pp.- [11] Vincent A. Schmidt and...gas, Nevada, 2002. sets. Macroeconomic Dynamics, 1:485-512, 1997. Reprinted in Barnett, WA. [12] Vincent A. Schmidt and Jane M. Binner. and Serletis
Robust Sensitivity Analysis of Courses of Action Using an Additive Value Model
2008-03-01
According to Clemen , sensitivity analysis answers, “What makes a difference in this decision?” (2001:175). Sensitivity analysis can also indicate...alternative to change. These models look for the new weighting that causes a specific alternative to rank above all others. 19 Barron and Schmidt first... Schmidt , 1988:123). A smaller objective function value indicates greater sensitivity. Wolters and Mareschal propose a similar approach using goal
Morino, Chisato; Morita, Yusuke; Minami, Kazuki; Nishidono, Yuto; Nakashima, Yoshitaka; Ozawa, Rika; Takabayashi, Junji; Ono, Naoaki; Kanaya, Shigehiko; Tamura, Takayuki; Tezuka, Yasuhiro; Tanaka, Ken
2018-01-01
Umbelliferous medicinal plants, such as Angelica acutiloba Kitagawa and Angelica dahurica Bentham et Hooker filius ex Franchet et Savatier, account for a large percentage of crude drug consumption in Japan. The most serious problem in the cultivation of umbelliferous medicinal plants is the feeding damage caused by the common yellow swallowtail (Papilio machaon hippocrates C. & R. Felder, 1864). When we compared the numbers of eggs laid by P. machaon on six umbelliferous medicinal plants, the eggs on A. acutiloba, A. dahurica, and Glehnia littoralis Fr. Schmidt ex Miquel were the most numerous, those on Saposhnikovia divaricata Schischkin and Cnidium officinale Makino were rare, and Bupleurum falcatum Linné was not oviposited at all. To identify oviposition inhibitors for P. machaon in B. falcatum, S. divaricata, and C. officinale, the volatile chemical constituents of these umbelliferous medicinal plants were compared with GC-MS. We carried out multivariate analysis of gas chromatographic data and concluded that germacrene D, α-humulene, and trans-caryophyllene play important roles in protecting plants from oviposition by P. machaon. Their oviposition repellent activity was confirmed by the fact that the number of eggs laid on the leaves around a repellent device containing a mixture of germacrene D, α-humulene, and trans-caryophyllene was reduced by 40% compared to a control.
Inertial Manifold and Large Deviations Approach to Reduced PDE Dynamics
NASA Astrophysics Data System (ADS)
Cardin, Franco; Favretti, Marco; Lovison, Alberto
2017-09-01
In this paper a certain type of reaction-diffusion equation—similar to the Allen-Cahn equation—is the starting point for setting up a genuine thermodynamic reduction i.e. involving a finite number of parameters or collective variables of the initial system. We firstly operate a finite Lyapunov-Schmidt reduction of the cited reaction-diffusion equation when reformulated as a variational problem. In this way we gain a finite-dimensional ODE description of the initial system which preserves the gradient structure of the original one and that is exact for the static case and only approximate for the dynamic case. Our main concern is how to deal with this approximate reduced description of the initial PDE. To start with, we note that our approximate reduced ODE is similar to the approximate inertial manifold introduced by Temam and coworkers for Navier-Stokes equations. As a second approach, we take into account the uncertainty (loss of information) introduced with the above mentioned approximate reduction by considering the stochastic version of the ODE. We study this reduced stochastic system using classical tools from large deviations, viscosity solutions and weak KAM Hamilton-Jacobi theory. In the last part we suggest a possible use of a result of our approach in the comprehensive treatment non equilibrium thermodynamics given by Macroscopic Fluctuation Theory.
NASA Astrophysics Data System (ADS)
Chitra, M.; Suhasini, M.
2018-04-01
In this paper, we investigate the effect of chemical reaction on the unsteady oscillatory MHD flow through porous medium in a porous vertical channel in the presence of suction velocity. The flow is assumed to be incompressible electrically conducting and radiating viscoelastic fluid in the presence of uniform magnetic flied applied perpendicular to the plane of the plates of the channel. The closed forms of analytical solution are obtained for the momentum, energy and concentration equation. The effect of various flow parameters like Schmidt number, chemical radiation parameter, Grashof number, solutal Grashof number on velocity profile, temperature, concentration, wall shear stress, and the rate of heat and mass transfer are obtained and their behaviour are discussed graphically.
Faint blue objects at high Galactic latitude. V - Palomar Schmidt field centered on selected area 71
NASA Technical Reports Server (NTRS)
Usher, Peter D.; Mitchell, Kenneth J.; Warnock, Archibald, III
1988-01-01
Starlike objects with both blue and ultraviolet excess have been selected from a Palomar 1.2 m Schmidt field centered on Kapteyn selected area 71. The method of selection is that used in the previous papers of this series, but modified to account for the differential reddening that occurs across the field. The color classes, color subclasses, positions, and magnitudes of the selected objects are listed.
Motiwala, Hashim F; Yin, Qin; Aubé, Jeffrey
2015-12-29
The Schmidt reaction of aromatic aldehydes using a substoichiometric amount (40 mol %) of triflic acid is described. Low catalyst loading was enabled by a strong hydrogen-bond-donating solvent hexafluoro-2-propanol (HFIP). This improved protocol tolerates a broad scope of aldehydes with diverse functional groups and the corresponding nitriles were obtained in good to high yields without the need for aqueous work up.
NASA Astrophysics Data System (ADS)
Feng, Hua; Olsen, Michael G.; Hill, James C.; Fox, Rodney O.
2007-06-01
Simultaneous velocity and concentration fields in a confined liquid-phase rectangular jet with a Reynolds number based on the hydraulic diameter of 50,000 (or 10,000 based on the velocity difference between streams and the jet exit dimension) and a Schmidt number of 1,250 were obtained by means of a combined particle image velocimetry (PIV) and planar laser-induced fluorescence (PLIF) system. Data were collected at the jet exit and six further downstream locations. The velocity and concentration field data were analyzed for flow statistics such as turbulent fluxes, turbulent viscosity and diffusivity, and turbulent Schmidt number ( Sc T ). The streamwise turbulent flux was found to be larger than the transverse turbulent flux, and the mean concentration gradient was not aligned with the turbulent flux vector. The average Sc T was found to vary both in streamwise and in cross stream directions and had a mean value around 0.8, a value consistent with the literature. Spatial correlation fields of turbulent fluxes and concentration were then determined. The R u'ϕ' correlation was elliptical in shape with a major axis tilted downward with respect to the streamwise axis, whereas the R v'ϕ' correlation was an ellipse with a major axis aligned with the cross-stream direction. Negative regions of R u'ϕ' were observed in the outer streams, and these negatively correlated regions decayed with downstream distance and finally disappeared altogether. The R ϕ'ϕ' correlation field was found to be an ellipse with the major axis inclined at about 45° with respect to the streamwise direction. Linear stochastic estimation was used to interpret spatial correlation data and to determine conditional flow structures. It is believed that a vortex street formed near the splitter plate is responsible for the negatively correlated region observed in the R u'ϕ' spatial correlations of turbulent fluxes. A positive concentration fluctuation event was observed to correspond to a finger of nearly uniform concentration fluid reaching out into the outer stream, whereas a negative event corresponds to a pocket of nearly uniform fluid being entrained from the outer stream into the center jet region. Large-scale vortical structures were observed in the conditional velocity fields with an elliptical shape and a streamwise major axis. The growth of the structure size increased linearly initially but then grew more slowly as the flow transitioned toward channel flow.
Mehl, Heidi E.; Schmidt, Heather C. Ross; Pope, Larry M.
2007-01-01
Water-quality samples were collected from surface- (stream-) and ground-water sites on and near the Prairie Band Potawatomi Reservation in northeastern Kansas (fig. 1) from June 1996 through August 2006 as part of a cooperative study between the U.S. Geological Survey (USGS) and the Prairie Band Potawatomi Nation (Schmidt and others, 2007). Surface- and ground-water quality were evaluated using applicable drinking-water standards to consider whether these resources can be used in the future to supply drinking water for the reservation. Presently (2007), drinking water on the reservation is purchased from Rural Water District #3 in Jackson County (Sharon Bosse, Prairie Band Potawatomi Nation Department of Planning and Environmental Protection, oral commun., 2007). Results of water-quality analyses are summarized in the following sections. Water-quality activities for this study are documented in several reports (Trombley, 1999, 2001; Schmidt, 2004; Schmidt and others, 2007).
The Liverpool-Edinburgh high proper motion catalogue
NASA Astrophysics Data System (ADS)
Pokorny, R. S.; Jones, H. R. A.; Hambly, N. C.; Pinfield, D. J.
2004-07-01
We present a machine selected catalogue of 11 289 objects with proper motions exceeding 0.18 arcsec yr-1 and an R-band faint magnitude limit of 19.5 mag. The catalogue was produced using SuperCOSMOS digitized R-Band ESO and UK Schmidt Plates in 287 Schmidt fields covering almost 7000 square degrees (˜17% of the whole sky) at the South Galactic Cap. The catalogue includes UK Schmidt BJ and I magnitudes for all of the stars as well as 2MASS magnitudes for 10,447 of the catalogue stars. We also show that the NLTT is ˜95% complete for Dec > -32.5°. The full Table \\ref{tab1} is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/421/763
Development of High-Activity Para- to Ortho-Hydrogen Conversion Catalysts. Volume 2
1989-09-28
Proc. Roy. Soc. London AllO, 464 (1925). 2 1929 Para- and ortho-hydrogen, Barmois, E., La Nature No. 2820, 400-1 (1929) C.A. 24,, 1020b. K. F...U.S. At. Energy Comm. LA -2719, 40 pp. (1962); cf. 3. Chem. Eng. Data 7, 179(1962). C.A. 58, 10750g. Schmidt number for normal hydrogen and...A-L);- p 181-9; in Eng. Briones, A. G.; Garcia de la Banda, J. F.; Inst. Quim. Fis. Quim., Madrid, Anales Real. Soc. Espan. Fis. Quim. (Madrid); Ser
Prediction of free turbulent mixing using a turbulent kinetic energy method
NASA Technical Reports Server (NTRS)
Harsha, P. T.
1973-01-01
Free turbulent mixing of two-dimensional and axisymmetric one- and two-stream flows is analyzed by a relatively simple turbulent kinetic energy method. This method incorporates a linear relationship between the turbulent shear and the turbulent kinetic energy and an algebraic relationship for the length scale appearing in the turbulent kinetic energy equation. Good results are obtained for a wide variety of flows. The technique is shown to be especially applicable to flows with heat and mass transfer, for which nonunity Prandtl and Schmidt numbers may be assumed.
Evaluation of large format electron bombarded virtual phase CCDs as ultraviolet imaging detectors
NASA Technical Reports Server (NTRS)
Opal, Chet B.; Carruthers, George R.
1989-01-01
In conjunction with an external UV-sensitive cathode, an electron-bombarded CCD may be used as a high quantum efficiency/wide dynamic range photon-counting UV detector. Results are presented for the case of a 1024 x 1024, 18-micron square pixel virtual phase CCD used with an electromagnetically focused f/2 Schmidt camera, which yields excellent simgle-photoevent discrimination and counting efficiency. Attention is given to the vacuum-chamber arrangement used to conduct system tests and the CCD electronics and data-acquisition systems employed.
Gibbs measures based on 1d (an)harmonic oscillators as mean-field limits
NASA Astrophysics Data System (ADS)
Lewin, Mathieu; Nam, Phan Thành; Rougerie, Nicolas
2018-04-01
We prove that Gibbs measures based on 1D defocusing nonlinear Schrödinger functionals with sub-harmonic trapping can be obtained as the mean-field/large temperature limit of the corresponding grand-canonical ensemble for many bosons. The limit measure is supported on Sobolev spaces of negative regularity, and the corresponding density matrices are not trace-class. The general proof strategy is that of a previous paper of ours, but we have to complement it with Hilbert-Schmidt estimates on reduced density matrices.
Group size effect on cooperation in one-shot social dilemmas
Barcelo, Hélène; Capraro, Valerio
2015-01-01
Social dilemmas are central to human society. Depletion of natural resources, climate protection, security of energy supply, and workplace collaborations are all examples of social dilemmas. Since cooperative behaviour in a social dilemma is individually costly, Nash equilibrium predicts that humans should not cooperate. Yet experimental studies show that people do cooperate even in anonymous one-shot interactions. In spite of the large number of participants in many modern social dilemmas, little is known about the effect of group size on cooperation. Does larger group size favour or prevent cooperation? We address this problem both experimentally and theoretically. Experimentally, we find that there is no general answer: it depends on the strategic situation. Specifically, we find that larger groups are more cooperative in the Public Goods game, but less cooperative in the N-person Prisoner's dilemma. Theoretically, we show that this behaviour is not consistent with either the Fehr & Schmidt model or (a one-parameter version of) the Charness & Rabin model, but it is consistent with the cooperative equilibrium model introduced by the second author. PMID:25605124
NASA Astrophysics Data System (ADS)
Atapour, Hadi; Mortazavi, Ali
2018-04-01
The effects of textural characteristics, especially grain size, on index properties of weakly solidified artificial sandstones are studied. For this purpose, a relatively large number of laboratory tests were carried out on artificial sandstones that were produced in the laboratory. The prepared samples represent fifteen sandstone types consisting of five different median grain sizes and three different cement contents. Indices rock properties including effective porosity, bulk density, point load strength index, and Schmidt hammer values (SHVs) were determined. Experimental results showed that the grain size has significant effects on index properties of weakly solidified sandstones. The porosity of samples is inversely related to the grain size and decreases linearly as grain size increases. While a direct relationship was observed between grain size and dry bulk density, as bulk density increased with increasing median grain size. Furthermore, it was observed that the point load strength index and SHV of samples increased as a result of grain size increase. These observations are indirectly related to the porosity decrease as a function of median grain size.
Rashidi, Mohammad M.; Kavyani, Neda; Abelman, Shirley; Uddin, Mohammed J.; Freidoonimehr, Navid
2014-01-01
In this study combined heat and mass transfer by mixed convective flow along a moving vertical flat plate with hydrodynamic slip and thermal convective boundary condition is investigated. Using similarity variables, the governing nonlinear partial differential equations are converted into a system of coupled nonlinear ordinary differential equations. The transformed equations are then solved using a semi-numerical/analytical method called the differential transform method and results are compared with numerical results. Close agreement is found between the present method and the numerical method. Effects of the controlling parameters, including convective heat transfer, magnetic field, buoyancy ratio, hydrodynamic slip, mixed convective, Prandtl number and Schmidt number are investigated on the dimensionless velocity, temperature and concentration profiles. In addition effects of different parameters on the skin friction factor, , local Nusselt number, , and local Sherwood number are shown and explained through tables. PMID:25343360
Hethnawi, Afif; Manasrah, Abdallah D; Vitale, Gerardo; Nassar, Nashaat N
2018-03-01
In this study, a fixed-bed column adsorption process was employed to remove organic pollutants from a real industrial wastewater effluent using polyethylenimine-functionalized pyroxene nanoparticles (PEI-PY) embedded into Diatomite at very low mass percentage. Various dynamic parameters (e.g., inlet concentration, inlet flow rate, bed height, and PEI-nanoparticle concentration in Diatomite, (%nps)) were investigated to determine the breakthrough behavior. The obtained breakthrough curves were fit with a convection-dispersion model to determine the characteristic parameters based on mass transfer phenomena. The axial dispersion coefficient (D L ) and group of dimensionless numbers; including Renold number (Re), Schmidt number (Sc), and Sherwood number (Sh) were all determined and correlated by Wilson-Geankoplis correlation that was used to estimate the external film diffusion coefficients (Kc) at 0.0015 < Re<55. Copyright © 2017 Elsevier Inc. All rights reserved.
Brorfelde Schmidt CCD Catalog (BSCC)
2010-06-23
reference stars. Errors of individual positions are about 20 to 200 mas for stars in the R = 10 to 18 mag range. External comparisons with 2MASS and SDSS...reveal possible small systematic errors in the BSCC of up to about 30 mas. The catalog is supplemented with J, H, and Ks magnitudes from the 2MASS ...Survey ( 2MASS ) near-infrared photometry added to the catalog (2). The fil- ters used at the Brorfelde Schmidt for this project are approximating the
Mathematical approach to recover EEG brain signals with artifacts by means of Gram-Schmidt transform
NASA Astrophysics Data System (ADS)
Runnova, A. E.; Zhuravlev, M. O.; Koronovskiy, A. A.; Hramov, A. E.
2017-04-01
A novel method for removing oculomotor artifacts on electroencephalographical signals is proposed and based on the orthogonal Gram-Schmidt transform using electrooculography data. The method has shown high efficiency removal of artifacts caused by spontaneous movements of the eyeballs (about 95-97% correct remote oculomotor artifacts). This method may be recommended for multi-channel electroencephalography data processing in an automatic on-line in a variety of psycho-physiological experiments.
NASA Astrophysics Data System (ADS)
Mazzinghi, Piero; Bratina, Vojko; Gambicorti, Lisa; Simonetti, Francesca; Zuccaro Marchi, Alessandro
2017-11-01
New technologies are proposed for large aperture and wide Field of View (FOV) space telescopes dedicated to detection of Ultra High Energy Cosmic Rays and Neutrinos flux, through observation of fluorescence traces in atmosphere and diffused Cerenkov signals. The presented advanced detection system is a spaceborne LEO telescope, with better performance than ground-based observatories, detecting up to 103 - 104 events/year. Different design approaches are implemented, all with very large FOV and focal surface detectors with sufficient segmentation and time resolution to allow precise reconstructions of the arrival direction. In particular, two Schmidt cameras are suggested as an appropriate solution to match most of the optical and technical requirements: large FOV, low f/#, reduction of stray light, optionally flat focal surface, already proven low-cost construction technologies. Finally, a preliminary proposal of a wideFOV retrofocus catadioptric telescope is explained.
Random pure states: Quantifying bipartite entanglement beyond the linear statistics.
Vivo, Pierpaolo; Pato, Mauricio P; Oshanin, Gleb
2016-05-01
We analyze the properties of entangled random pure states of a quantum system partitioned into two smaller subsystems of dimensions N and M. Framing the problem in terms of random matrices with a fixed-trace constraint, we establish, for arbitrary N≤M, a general relation between the n-point densities and the cross moments of the eigenvalues of the reduced density matrix, i.e., the so-called Schmidt eigenvalues, and the analogous functionals of the eigenvalues of the Wishart-Laguerre ensemble of the random matrix theory. This allows us to derive explicit expressions for two-level densities, and also an exact expression for the variance of von Neumann entropy at finite N,M. Then, we focus on the moments E{K^{a}} of the Schmidt number K, the reciprocal of the purity. This is a random variable supported on [1,N], which quantifies the number of degrees of freedom effectively contributing to the entanglement. We derive a wealth of analytical results for E{K^{a}} for N=2 and 3 and arbitrary M, and also for square N=M systems by spotting for the latter a connection with the probability P(x_{min}^{GUE}≥sqrt[2N]ξ) that the smallest eigenvalue x_{min}^{GUE} of an N×N matrix belonging to the Gaussian unitary ensemble is larger than sqrt[2N]ξ. As a by-product, we present an exact asymptotic expansion for P(x_{min}^{GUE}≥sqrt[2N]ξ) for finite N as ξ→∞. Our results are corroborated by numerical simulations whenever possible, with excellent agreement.
Hydrogen and hydrocarbon diffusion flames in a weightless environment
NASA Technical Reports Server (NTRS)
Haggard, J. B., Jr.; Cochran, T. H.
1973-01-01
An experimental investigation was performed on laminar hydrogen-, ethylene-, and propylene-air diffusion burning in a weightless environment. The flames burned on nozzles with radii ranging from 0.051 to 0.186 cm with fuel Reynolds numbers at the nozzle exit from 9 to 410. Steady-state diffusion flames existed in a weightless environment for all the fuels tested. A correlation was obtained for their axial length as a function of Schmidt number, Reynolds numbers, and stoichiometric mole fraction. The maximum flame radii were correlated with the ratio of nozzle radius to average fuel velocity. The flames of ethylene and propylene on nozzles with radii 0.113 or larger appeared to be constantly changing color and/or length throughout the test. No extinguishment was observed for any of the gases tested within the 2.2 seconds of weightlessness.
2014-01-01
This paper presents an incompressible two-dimensional heat and mass transfer of an electrically conducting micropolar fluid flow in a porous medium between two parallel plates with chemical reaction, Hall and ion slip effects. Let there be periodic injection or suction at the lower and upper plates and the nonuniform temperature and concentration at the plates are varying periodically with time. The flow field equations are reduced to nonlinear ordinary differential equations using similarity transformations and then solved numerically by quasilinearization technique. The profiles of velocity components, microrotation, temperature distribution and concentration are studied for different values of fluid and geometric parameters such as Hartmann number, Hall and ion slip parameters, inverse Darcy parameter, Prandtl number, Schmidt number, and chemical reaction rate and shown in the form of graphs. PMID:27419211
NASA Astrophysics Data System (ADS)
Hayat, Tasawar; Qayyum, Sumaira; Alsaedi, Ahmed; Ahmad, Bashir
2018-03-01
Flow of second grade fluid by a rotating disk with heat and mass transfer is discussed. Additional effects of heat generation/absorption are also analyzed. Flow is also subjected to homogeneous-heterogeneous reactions. The convergence of computed solution is assured through appropriate choices of initial guesses and auxiliary parameters. Investigation is made for the effects of involved parameters on velocities (radial, axial, tangential), temperature and concentration. Skin friction and Nusselt number are also analyzed. Graphical results depict that an increase in viscoelastic parameter enhances the axial, radial and tangential velocities. Opposite behavior of temperature is observed for larger values of viscoelastic and heat generation/absorption parameters. Concentration profile is increasing function of Schmidt number, viscoelastic parameter and heterogeneous reaction parameter. Magnitude of skin friction and Nusselt number are enhanced for larger viscoelastic parameter.
NASA Astrophysics Data System (ADS)
Fan, Hong-Yi; Fan, Yue
2002-01-01
By virtue of the technique of integration within an ordered product of operators and the Schmidt decomposition of the entangled state |η〉, we reduce the general projection calculation in the theory of quantum teleportation to a as simple as possible form and present a general formalism for teleportating quantum states of continuous variable. The project supported by National Natural Science Foundation of China and Educational Ministry Foundation of China
Muzzle Blast Pressure Loadings upon Aircraft Surfaces
1984-02-01
0.02 m Aluminum plate. The plate is instrumented with a linear array of ten piezoelectric pressure transducers, Kistler Model 201B5. The plate is...maintained to insure compatibility of the various sets of 7. E. M. Schmidt, E. J. Gion, and D. D. Shear, "Acoustic Thermometric Measurements of...s -’-’»VA»’ ^I*T^^,*^^T^7.^ MVV-V-VV VV-V-V’-T-^ *7»T REFERENCES 7. E. M. Schmidt, E. J. Gion, and D. D. Shear, "Acoustic Thermometric
NASA Astrophysics Data System (ADS)
Hoover, Wm. G.; Hoover, Carol G.
2012-02-01
We compare the Gram-Schmidt and covariant phase-space-basis-vector descriptions for three time-reversible harmonic oscillator problems, in two, three, and four phase-space dimensions respectively. The two-dimensional problem can be solved analytically. The three-dimensional and four-dimensional problems studied here are simultaneously chaotic, time-reversible, and dissipative. Our treatment is intended to be pedagogical, for use in an updated version of our book on Time Reversibility, Computer Simulation, and Chaos. Comments are very welcome.
Hilbert-Schmidt Measure of Pairwise Quantum Discord for Three-Qubit X States
NASA Astrophysics Data System (ADS)
Daoud, M.; Laamara, R. Ahl; Seddik, S.
2015-10-01
The Hilbert-Schmidt distance between a mixed three-qubit state and its closest state is used to quantify the amount of pairwise quantum correlations in a tripartite system. Analytical expressions of geometric quantum discord are derived. A particular attention is devoted to two special classes of three-qubit X states. They include three-qubit states of W, GHZ and Bell type. We also discuss the monogamy property of geometric quantum discord in some mixed three-qubit systems.
Rank-k modification methods for recursive least squares problems
NASA Astrophysics Data System (ADS)
Olszanskyj, Serge; Lebak, James; Bojanczyk, Adam
1994-09-01
In least squares problems, it is often desired to solve the same problem repeatedly but with several rows of the data either added, deleted, or both. Methods for quickly solving a problem after adding or deleting one row of data at a time are known. In this paper we introduce fundamental rank-k updating and downdating methods and show how extensions of rank-1 downdating methods based on LINPACK, Corrected Semi-Normal Equations (CSNE), and Gram-Schmidt factorizations, as well as new rank-k downdating methods, can all be derived from these fundamental results. We then analyze the cost of each new algorithm and make comparisons tok applications of the corresponding rank-1 algorithms. We provide experimental results comparing the numerical accuracy of the various algorithms, paying particular attention to the downdating methods, due to their potential numerical difficulties for ill-conditioned problems. We then discuss the computation involved for each downdating method, measured in terms of operation counts and BLAS calls. Finally, we provide serial execution timing results for these algorithms, noting preferable points for improvement and optimization. From our experiments we conclude that the Gram-Schmidt methods perform best in terms of numerical accuracy, but may be too costly for serial execution for large problems.
Universality of Schmidt decomposition and particle identity
NASA Astrophysics Data System (ADS)
Sciara, Stefania; Lo Franco, Rosario; Compagno, Giuseppe
2017-03-01
Schmidt decomposition is a widely employed tool of quantum theory which plays a key role for distinguishable particles in scenarios such as entanglement characterization, theory of measurement and state purification. Yet, its formulation for identical particles remains controversial, jeopardizing its application to analyze general many-body quantum systems. Here we prove, using a newly developed approach, a universal Schmidt decomposition which allows faithful quantification of the physical entanglement due to the identity of particles. We find that it is affected by single-particle measurement localization and state overlap. We study paradigmatic two-particle systems where identical qubits and qutrits are located in the same place or in separated places. For the case of two qutrits in the same place, we show that their entanglement behavior, whose physical interpretation is given, differs from that obtained before by different methods. Our results are generalizable to multiparticle systems and open the way for further developments in quantum information processing exploiting particle identity as a resource.
Universality of Schmidt decomposition and particle identity
Sciara, Stefania; Lo Franco, Rosario; Compagno, Giuseppe
2017-01-01
Schmidt decomposition is a widely employed tool of quantum theory which plays a key role for distinguishable particles in scenarios such as entanglement characterization, theory of measurement and state purification. Yet, its formulation for identical particles remains controversial, jeopardizing its application to analyze general many-body quantum systems. Here we prove, using a newly developed approach, a universal Schmidt decomposition which allows faithful quantification of the physical entanglement due to the identity of particles. We find that it is affected by single-particle measurement localization and state overlap. We study paradigmatic two-particle systems where identical qubits and qutrits are located in the same place or in separated places. For the case of two qutrits in the same place, we show that their entanglement behavior, whose physical interpretation is given, differs from that obtained before by different methods. Our results are generalizable to multiparticle systems and open the way for further developments in quantum information processing exploiting particle identity as a resource. PMID:28333163
Universality of Schmidt decomposition and particle identity.
Sciara, Stefania; Lo Franco, Rosario; Compagno, Giuseppe
2017-03-23
Schmidt decomposition is a widely employed tool of quantum theory which plays a key role for distinguishable particles in scenarios such as entanglement characterization, theory of measurement and state purification. Yet, its formulation for identical particles remains controversial, jeopardizing its application to analyze general many-body quantum systems. Here we prove, using a newly developed approach, a universal Schmidt decomposition which allows faithful quantification of the physical entanglement due to the identity of particles. We find that it is affected by single-particle measurement localization and state overlap. We study paradigmatic two-particle systems where identical qubits and qutrits are located in the same place or in separated places. For the case of two qutrits in the same place, we show that their entanglement behavior, whose physical interpretation is given, differs from that obtained before by different methods. Our results are generalizable to multiparticle systems and open the way for further developments in quantum information processing exploiting particle identity as a resource.
Renormalization group approach to symmetry protected topological phases
NASA Astrophysics Data System (ADS)
van Nieuwenburg, Evert P. L.; Schnyder, Andreas P.; Chen, Wei
2018-04-01
A defining feature of a symmetry protected topological phase (SPT) in one dimension is the degeneracy of the Schmidt values for any given bipartition. For the system to go through a topological phase transition separating two SPTs, the Schmidt values must either split or cross at the critical point in order to change their degeneracies. A renormalization group (RG) approach based on this splitting or crossing is proposed, through which we obtain an RG flow that identifies the topological phase transitions in the parameter space. Our approach can be implemented numerically in an efficient manner, for example, using the matrix product state formalism, since only the largest first few Schmidt values need to be calculated with sufficient accuracy. Using several concrete models, we demonstrate that the critical points and fixed points of the RG flow coincide with the maxima and minima of the entanglement entropy, respectively, and the method can serve as a numerically efficient tool to analyze interacting SPTs in the parameter space.
NASA Astrophysics Data System (ADS)
Vasu, B.; Gorla, Rama Subba Reddy; Murthy, P. V. S. N.
2017-05-01
The Walters-B liquid model is employed to simulate medical creams and other rheological liquids encountered in biotechnology and chemical engineering. This rheological model introduces supplementary terms into the momentum conservation equation. The combined effects of thermal radiation and heat sink/source on transient free convective, laminar flow and mass transfer in a viscoelastic fluid past a vertical plate are presented by taking thermophoresis effect into account. The transformed conservation equations are solved using a stable, robust finite difference method. A parametric study illustrating the influence of viscoelasticity parameter ( Γ), thermophoretic parameter ( τ), thermal radiation parameter ( F), heat sink/source ( ϕ), Prandtl number ( Pr), Schmidt number ( Sc), thermal Grashof number ( Gr), solutal Grashof number ( Gm), temperature and concentration profiles as well as local skin-friction, Nusselt and Sherwood number is conducted. The results of this parametric study are shown graphically and inform of table. The study has applications in polymer materials processing.
NASA Astrophysics Data System (ADS)
Richards, Jeremy P.
2001-12-01
Paterson and Schmidt (1999) and Schmidt and Paterson (2000) presented statistical analyses of spatial relationships between faults and plutons from which they ;see no evidence that magma is channeled along faults; (Paterson and Schmidt, 1999, p. 1140). If anything, they conclude, there is an antithetic relationship. As an economic geologist familiar with intrusion-related hydrothermal ore deposits, I was at first surprised by these statements and the bold title of the EOS article: ;Analyses fail to find coupling between deformation and magmatism.; However, after reading the articles I came to understand that these conclusions applied only to plutons emplaced within compressional orogenic belts. Fortunately, most hypabyssal plutons related to magmatic hydrothermal ore deposits are emplaced in tensional or transtensional arc environments, albeit perhaps within a broadly compressional regime. In such settings, structural controls on the localization of ore-forming magmatism are evident, as illustrated by the restriction of several of the world's largest porphyry copper deposits to a single ∼30 km×∼1000 km fault belt (the West Fissure Zone) in northern Chile and southern Peru (Fig. 1; Baker and Guilbert, 1987; Richards et al., 1999, 2001), and more specifically to lineament intersections along its length (Salfity, 1985; Richards, 2000; Richards et al., 2001). Other examples have been provided by Rehrig and Heidrick (1972), Seraphim and Hollister (1976), Titley (1981), Heidrick and Titley (1982), Sylvester and Linke (1993), Sapiie and Cloos (1995), and Cornejo et al. (1997).
Polydisperse effects in jet spray flames
NASA Astrophysics Data System (ADS)
Weinberg, Noam; Greenberg, J. Barry
2018-01-01
A laminar jet polydisperse spray diffusion flame is analysed mathematically for the first time using an extension of classical similarity solutions for gaseous jet flames. The analysis enables a comparison to be drawn between conditions for flame stability or flame blow-out for purely gaseous flames and for spray flames. It is found that, in contrast to the Schmidt number criteria relevant to gas flames, droplet size and initial spray polydispersity play a critical role in determining potential flame scenarios. Some qualitative agreement for lift-off height is found when comparing predictions of the theory and sparse independent experimental evidence from the literature.
NASA Technical Reports Server (NTRS)
Abel, I. R. (Inventor)
1974-01-01
A wide angle, low focal ratio, high resolution, catoptric, image plane scanner is described. The scanner includes the following features: (1) a reflective improvement on the Schmidt principle, (2) a polar line scanner in which all field elements are brought to and corrected on axis, and (3) a scanner arrangement in which the aperture stop of the system is imaged at the center of curvature of a spherical primary mirror. The system scans are a large radial angle and an extremely high rate of speed with relatively small scanning mirrors. Because the system is symmetrical about the optical axis, the obscuration is independent of the scan angle.
2011-08-01
Air Power Centre]), Col (GS) Thomas Lorber, FüAk (Führungsakademie); Lt Col Dr. Wolfgang Schmidt, Military- Historical Research Office, Potsdam; Lt Gen...Col (GS) Dr. Michael Wolfgang Romba, Col (GS) Hans-Dieter Schön and his staff, Col (GS) Lothar Schmidt, and Lt Col (GS) Michael Trautermann. In the...Multinational Air Wing (DMAW) Project,” accessed 2 March 2007, http://www.euroairgroup.org/act_DMAW.htm. 75. Wolfgang Lange, “Lufttransport—Ansätze
TAUKAM: a new prime-focus camera for the Tautenburg Schmidt Telescope
NASA Astrophysics Data System (ADS)
Stecklum, Bringfried; Eislöffel, Jochen; Klose, Sylvio; Laux, Uwe; Löwinger, Tom; Meusinger, Helmut; Pluto, Michael; Winkler, Johannes; Dionies, Frank
2016-08-01
TAUKAM stands for "TAUtenburg KAMera", which will become the new prime-focus imager for the Tautenburg Schmidt telescope. It employs an e2v 6kx6k CCD and is under manufacture by Spectral Instruments Inc. We describe the design of the instrument and the auxiliary components, its specifications as well as the concept for integrating the device into the telescope infrastructure. First light is foreseen in 2017. TAUKAM will boost the observational capabilities of the telescope for what concerns optical wide-field surveys.
NASA Technical Reports Server (NTRS)
Ahn, Doyeol; Chuang, S. L.
1986-01-01
Variational calculations of subband eigenstates in an infinite quantum well with an applied electric field using Gram-Schmidt orthogonalized trial wave functions are presented. The results agree very well with the exact numerical solutions even up to 1200 kV/cm. It is also shown that, for increasing electric fields, the energy of the ground state decreases, while that of higher subband states increases slightly up to 1000 kV/cm and then decreases for a well size of 100 A.
1988-03-10
comoat sunort Droblems put the 3d Battalion in a Drecarious Dosition On 4 November. First, the Kall River trail, the major route from the division to...was to maintain one- way traffic through to the Kall River bridge while Company A did the same from the bridge to Schmidt. C Company, in reserve...supply weasels from the 3d Battalion crossed the Kall . (52) Meanwhile, in Schmidt the 3d Battalion prepared to defend. * The battalion had no combined arms
NASA Astrophysics Data System (ADS)
Muller, A.
1988-09-01
The Director General of ESO, Harry van der Laan, invited me to La Silla as consultant during the realuminization and the optical trimming of the ESO Schmidt telescope. I was very happy with this invitation because it gave me an opportunity not only to spend some time at the Schmidt, but also to meet with many friends in Chile. At La Silla I had the good luck to meet Richard West who suggested to me to write a short contribution for the Messenger about my stay in Chile which I have done with pleasure.
Photometric Studies of Orbital Debris at GEO
NASA Technical Reports Server (NTRS)
Seitzer, Patrick; Cowardin, Heather M.; Barker, Ed; Abercromby, Kira J.; Foreman, Gary; Hortsman, Matt
2009-01-01
Orbital debris represents a significant and increasing risk to operational spacecraft. Here we report on photometric observations made in standard BVRI filters at the Cerro Tololo Inter-American Observatory (CTIO) in an effort to determine the physical characteristics of optically faint debris at geosynchronous Earth orbit (GEO). Our sample is taken from GEO objects discovered in a survey with the University of Michigan s 0.6-m Curtis-Schmidt telescope (known as MODEST, for Michigan Orbital DEbris Survey Telescope), and then followed up in real-time with the CTIO/SMARTS 0.9-m for orbits and photometry. For a sample of 50 objects, calibrated sequences in RB- V-I-R filters have been obtained with the CTIO/SMARTS 0.9-m. For objects that do not show large brightness variations, the colors are largely redder than solar in both B-R and R-I. The width of the color distribution may be intrinsic to the nature of the surfaces, but also could imply that we are seeing irregularly shaped objects and measuring the colors at different times with just one telescope. For irregularly shaped objects tumbling at unknown orientations and rates, such sequential filter measurements using one telescope are subject to large errors for interpretation. If all observations in all filters in a particular sequence are of the same surface at the same solar and viewing angles, then the colors are meaningful. Where this is not the case, interpretation of the observed colors is impossible. For a smaller sample of objects we have observed with synchronized CCD cameras on the two telescopes. The CTIO/SMARTS 0.9-m observes in B, and the Schmidt in R. The CCD cameras are electronically linked together so that the start time and duration of observations are both the same to better than 50 milliseconds. Now the observed B-R color is a true measure of the scattered illuminated area of the debris piece for that observation.
Convex geometry of quantum resource quantification
NASA Astrophysics Data System (ADS)
Regula, Bartosz
2018-01-01
We introduce a framework unifying the mathematical characterisation of different measures of general quantum resources and allowing for a systematic way to define a variety of faithful quantifiers for any given convex quantum resource theory. The approach allows us to describe many commonly used measures such as matrix norm-based quantifiers, robustness measures, convex roof-based measures, and witness-based quantifiers together in a common formalism based on the convex geometry of the underlying sets of resource-free states. We establish easily verifiable criteria for a measure to possess desirable properties such as faithfulness and strong monotonicity under relevant free operations, and show that many quantifiers obtained in this framework indeed satisfy them for any considered quantum resource. We derive various bounds and relations between the measures, generalising and providing significantly simplified proofs of results found in the resource theories of quantum entanglement and coherence. We also prove that the quantification of resources in this framework simplifies for pure states, allowing us to obtain more easily computable forms of the considered measures, and show that many of them are in fact equal on pure states. Further, we investigate the dual formulation of resource quantifiers, which provide a characterisation of the sets of resource witnesses. We present an explicit application of the results to the resource theories of multi-level coherence, entanglement of Schmidt number k, multipartite entanglement, as well as magic states, providing insight into the quantification of the four resources by establishing novel quantitative relations and introducing new quantifiers, such as a measure of entanglement of Schmidt number k which generalises the convex roof-extended negativity, a measure of k-coherence which generalises the \
Hybrid LES/RANS Simulation of Transverse Sonic Injection into a Mach 2 Flow
NASA Technical Reports Server (NTRS)
Boles, John A.; Edwards, Jack R.; Baurle, Robert A.
2008-01-01
A computational study of transverse sonic injection of air and helium into a Mach 1.98 cross-flow is presented. A hybrid large-eddy simulation / Reynolds-averaged Navier-Stokes (LES/RANS) turbulence model is used, with the two-equation Menter baseline (Menter-BSL) closure for the RANS part of the flow and a Smagorinsky-type model for the LES part of the flow. A time-dependent blending function, dependent on modeled turbulence variables, is used to shift the closure from RANS to LES. Turbulent structures are initiated and sustained through the use of a recycling / rescaling technique. Two higher-order discretizations, the Piecewise Parabolic Method (PPM) of Colella and Woodward, and the SONIC-A ENO scheme of Suresh and Huyhn are used in the study. The results using the hybrid model show reasonably good agreement with time-averaged Mie scattering data and with experimental surface pressure distributions, even though the penetration of the jet into the cross-flow is slightly over-predicted. The LES/RANS results are used to examine the validity of commonly-used assumptions of constant Schmidt and Prandtl numbers in the intense mixing zone downstream of the injection location.
Rashidi, Mohammad M; Kavyani, Neda; Abelman, Shirley; Uddin, Mohammed J; Freidoonimehr, Navid
2014-01-01
In this study combined heat and mass transfer by mixed convective flow along a moving vertical flat plate with hydrodynamic slip and thermal convective boundary condition is investigated. Using similarity variables, the governing nonlinear partial differential equations are converted into a system of coupled nonlinear ordinary differential equations. The transformed equations are then solved using a semi-numerical/analytical method called the differential transform method and results are compared with numerical results. Close agreement is found between the present method and the numerical method. Effects of the controlling parameters, including convective heat transfer, magnetic field, buoyancy ratio, hydrodynamic slip, mixed convective, Prandtl number and Schmidt number are investigated on the dimensionless velocity, temperature and concentration profiles. In addition effects of different parameters on the skin friction factor, [Formula: see text], local Nusselt number, [Formula: see text], and local Sherwood number [Formula: see text] are shown and explained through tables.
NASA Astrophysics Data System (ADS)
Khan, Sami Ullah; Shehzad, Sabir Ali; Rauf, Amar; Ali, Nasir
2018-03-01
The aim of this article is to highlight the unsteady mixed convective couple stress nanoliquid flow passed through stretching surface. The flow is generated due to periodic oscillations of sheet. An appropriate set of dimensionless variables are used to reduce the independent variables in governing equations arising from mathematical modeling. An analytical solution has been computed by employing the technique of homotopy method. The outcomes of various sundry parameters like couple stress parameter, the ratio of angular velocity to stretching rate, thermophoresis parameter, Hartmann number, Prandtl number, heat source/sink parameter, Schmidt number described graphically and in tabular form. It is observed that the velocity profile increases by increasing mixed convection parameter and concentration buoyancy parameter. The temperature enhances for larger values of Hartmann number and Brownian. The concentration profile increases by increasing thermophoresis parameter. Results show that wall shear stress increases by increasing couple stress parameter and ratio of oscillating frequency to stretching rate.
NASA Astrophysics Data System (ADS)
Kellerer-Pirklbauer, Andreas
2016-04-01
Rock glaciers are widespread permafrost landforms in Austria. Various rock glacier inventories list more than 4500 rock glaciers in the country; some 30-40% of them are intact. Relict (permafrost free) and pseudo-relict rock glaciers (sporadic and isolated permafrost particularly near the root zone) prevail in number. Rock glaciers are commonly formed over a period of several ka. Dating such landforms helps to understand palaeoclimatic conditions. In this study three rock glaciers consisting of gneiss were dated applying the Schmidt-hammer exposure-age dating (SHD) method. The rock glaciers are located at three neighbouring cirques in the Seckauer Tauern Range named Reichart Rock Glacier (RRG, area 1.26 km², length 1800 m, elevation range 1520-1940 m a.s.l.), Schöneben Rock Glacier (SRG, 0.11 km², 750 m, 1715-1905 m a.s.l.), and Dürrtal Rock Glacier (DRG, 0.08 km², 850 m, 1750-1980 m a.s.l.). RRG is one of the largest rock glaciers in Austria. All three landforms are influenced by lenses of permafrost at present (as indicated by ERT). During the LGM the Seckauer Tauern were covered by valley glaciers and deglaciation occurred presumably already early in the Alpine Lateglacial period. An analogue N-type Schmidt-hammer (proceq) was used for measuring the surface strength of stable blocks at the rock glacier surface by recording a rebound value (R-value) of a spring-loaded bolt. The R-value gives a relative measure of the surface hardness and hence time since exposure to weathering. Eight (RRG) or six (SRG, DRG) Schmidt-hammer measurement sites (with 50-100 individual readings) aligned along longitudinal transects (=former central flow line) between a talus slope (with relatively fresh boulders) in the root zone and the frontal ridge were measured. Mean R-value differences of 30.5 at RRG, 25.1 at SRG, and 20.7 at DRG were revealed along the three transects. The differences between the lowest and the highest R-value at the rock glaciers itself were 19.0 at RRG, 15.2 at SRG, and 10.5 at DRG. The differences in R-values between the talus slopes and the uppermost Schmidt-hammer site at the rock glacier were 11.5 at RRG, 9.9 at SRG, and 10.2 at DRG. No high-quality age control points are available at the studied rock glacier. Therefore, an age-calibration curve cannot be established. An age-calibration curve for gneiss has been established previously for a rock glacier c.110 km west of the study area yielding a mean decrease of 1.46 R/1 ka. This allows the estimate that the rock glacier formation period in the study area stretched over a period of several ka. Not unlikely, the formation of the rock glaciers was initiated already during the Gschnitz stadial (Heinrich 1 ice rafting event) dated to 15.4 ka BP or even earlier. SRG is the oldest rock glacier possibly starting to form during the later part of the Lateglacial ice decay-phase. At least 7-8 ka ago the stabilisation of the uppermost part of the three rock glaciers was accomplished. This rather late stabilisation might be also related to the thermally inert response of coarse rock glacier systems.
Hilbert-Schmidt quantum coherence in multi-qudit systems
NASA Astrophysics Data System (ADS)
Maziero, Jonas
2017-11-01
Using Bloch's parametrization for qudits ( d-level quantum systems), we write the Hilbert-Schmidt distance (HSD) between two generic n-qudit states as an Euclidean distance between two vectors of observables mean values in R^{Π_{s=1}nds2-1}, where ds is the dimension for qudit s. Then, applying the generalized Gell-Mann's matrices to generate SU(ds), we use that result to obtain the Hilbert-Schmidt quantum coherence (HSC) of n-qudit systems. As examples, we consider in detail one-qubit, one-qutrit, two-qubit, and two copies of one-qubit states. In this last case, the possibility for controlling local and non-local coherences by tuning local populations is studied, and the contrasting behaviors of HSC, l1-norm coherence, and relative entropy of coherence in this regard are noticed. We also investigate the decoherent dynamics of these coherence functions under the action of qutrit dephasing and dissipation channels. At last, we analyze the non-monotonicity of HSD under tensor products and report the first instance of a consequence (for coherence quantification) of this kind of property of a quantum distance measure.
Kennicutt-Schmidt Law in the Central Region of NGC 4321 as Seen by ALMA
Azeez, Jazeel H.; Hwang, C.-Y.; Abidin, Zamri Z.; Ibrahim, Zainol A.
2016-01-01
We present the Atacama Large Millimeter/Sub-millimeter Array (ALMA) cycle-0 science verification data of the CO(1–0) line emission in the central region of NGC 4321 (also known as M100) at the distance of 17.1 Mpc and VLA, L-band data of HI of the same galaxy. We have drawn the center area of M100 in the 12CO(J = 1–0) line with the resolution of (3.87″ × 2.53″) as viewed by ALMA, along with HI and Spitzer 8 and 3.6 μm data. The relationship between the surface density of molecular gas mass ∑H2 and that of star formation rate ∑SFR has been investigated, in addition to the relationship between the surface density of the neutral atomic hydrogen mass and that of ∑SFR (Kennicutt–Schmidt law) in this galaxy with a high spatial resolution. The results indicate that a significant correlation exists between the SFR surface density and the molecular gas mass density in the ~2 kpc region. The power-law index has been determined for three regions: center, upper and lower arms. The value of this index in the center region is 1.13, which follows the traditional (K-S) law and indicates that the molecular gas is affected by star formation. PMID:27247251
Saitoh, Yurika; Ohno, Nobuhiko; Komada, Masayuki; Saitoh, Sei; Peles, Elior; Ohno, Shinichi
2012-01-01
Protein 4.1G is a membrane skeletal protein found in specific subcellular structures in myelinated Schwann cells and seminiferous tubules. Here, we show that in the mouse sciatic nerve, protein 4.1G colocalized at Schmidt-Lanterman incisures (SLI) and the paranodes with a member of the membrane-associated guanylate kinase (MAGUK) family, membrane protein palmitoylated 6 (MPP6). Coimmunoprecipitation experiments revealed that MPP6 was interacting with protein 4.1G. In contrast to wild-type nerves, in 4.1G knockout mice, MPP6 was found largely in the cytoplasm near Schwann cell nuclei, indicating an abnormal protein transport. Although the SLI remained in the 4.1G knockout sciatic nerves, as confirmed by E-cadherin immunostaining, their shape was altered in aged 4.1G knockout nerves compared to their shape in wild-type nerves. In the seminiferous tubules, MPP6 was localized similarly to protein 4.1G along cell membranes of the spermatogonium and early spermatocytes. However, in contrast to myelinated peripheral nerves, the specific localization of MPP6 in the seminiferous tubules was unaltered in the absence of protein 4.1G. These results indicate that 4.1G has a specific role in the targeting of MPP6 to the SLI and the assembly of these subcellular structures. PMID:22025680
Psychological aspects of retirement: About Schmidt (2002), and Everybody's Fine (2009).
Wolman, Thomas
2011-06-01
With the films About Schmidt and Everybody's Fine as his main point of reference, the author elucidates the complex and often melancholic sojourn that follows ordinary men's retirement from their jobs. As this usually occurs during late middle age, the complicating variable of spousal loss, departure of children from the family home, a failing body, and social marginalization also get added to the picture. The vicissitudes of the resulting intrapsychic and interpersonal upheaval can lead to depressive withdrawal or a renewed effort at finding meaning in life. Ego resilience is tested and sublimation and creativity, if possible, save the day.
The Tidbinbilla-U.K. Schmidt radio quasar identification program
NASA Technical Reports Server (NTRS)
Jauncey, D. L.; Batty, M. J.; Savage, A.; Gulkis, S.
1983-01-01
A program is under way at Tidbinbilla to measure accurate (up to 2 arcsec r.m.s) radio positions for compact sources in the Parkes 2.7 GHz survey south of declination -30 deg. Optical identifications are being made on the basis of radio-optical position coincidence alone, without regard to colour or morphology, using the U.K. Schmidt IIIa-J sky survey to a limiting magnitude of 22.5. This program is aimed at producing an evaluation of the radio quasar redshift distribution with particular emphasis on those objects with redshifts greater than 3.0.
Frankowski, Kevin J.; Golden, Jennifer E.; Zeng, Yibin; Lei, Yao; Aubé, Jeffrey
2009-01-01
A tandem Diels-Alder/azido Schmidt reaction sequence provides rapid access to the core skeleton shared by several Stemona alkaloids including stenine, neostenine, tuberstemonine, and neotubererostemonine. The discovery and evolution of inter- and intramolecular variations of this process and their applications to total syntheses of (±)–stenine and (±)–neostenine is described. The stereochemical outcome of the reaction depends on both substrate type and reaction condition, enabling the preparation of both (±)–stenine and (±)–neostenine from the same diene/dienophile combination. PMID:18396881
Marangoni effect on small-amplitude capillary waves in viscous fluids
NASA Astrophysics Data System (ADS)
Shen, Li; Denner, Fabian; Morgan, Neal; van Wachem, Berend; Dini, Daniele
2017-11-01
We derive a general integro-differential equation for the transient behavior of small-amplitude capillary waves on the planar surface of a viscous fluid in the presence of the Marangoni effect. The equation is solved for an insoluble surfactant solution in concentration below the critical micelle concentration undergoing convective-diffusive surface transport. The special case of a diffusion-driven surfactant is considered near the the critical damping wavelength. The Marangoni effect is shown to contribute to the overall damping mechanism, and a first-order term correction to the critical wavelength with respect to the surfactant concentration difference and the Schmidt number is proposed.
Flow-induced separation in wall turbulence.
Nguyen, Quoc; Srinivasan, Chiranth; Papavassiliou, Dimitrios V
2015-03-01
One of the defining characteristics of turbulence is its ability to promote mixing. We present here a case where the opposite happens-simulation results indicate that particles can separate near the wall of a turbulent channel flow, when they have sufficiently different Schmidt numbers without use of any other means. The physical mechanism of the separation is understood when the interplay between convection and diffusion, as expressed by their characteristic time scales, is considered, leading to the determination of the necessary conditions for a successful separation between particles. Practical applications of these results can be found when very small particles need to be separated or removed from a fluid.
Spectral density of mixtures of random density matrices for qubits
NASA Astrophysics Data System (ADS)
Zhang, Lin; Wang, Jiamei; Chen, Zhihua
2018-06-01
We derive the spectral density of the equiprobable mixture of two random density matrices of a two-level quantum system. We also work out the spectral density of mixture under the so-called quantum addition rule. We use the spectral densities to calculate the average entropy of mixtures of random density matrices, and show that the average entropy of the arithmetic-mean-state of n qubit density matrices randomly chosen from the Hilbert-Schmidt ensemble is never decreasing with the number n. We also get the exact value of the average squared fidelity. Some conjectures and open problems related to von Neumann entropy are also proposed.
Electronographic cameras for space astronomy.
NASA Technical Reports Server (NTRS)
Carruthers, G. R.; Opal, C. B.
1972-01-01
Magnetically-focused electronographic cameras have been under development at the Naval Research Laboratory for use in far-ultraviolet imagery and spectrography, primarily in astronomical and optical-geophysical observations from sounding rockets and space vehicles. Most of this work has been with cameras incorporating internal optics of the Schmidt or wide-field all-reflecting types. More recently, we have begun development of electronographic spectrographs incorporating an internal concave grating, operating at normal or grazing incidence. We also are developing electronographic image tubes of the conventional end-window-photo-cathode type, for far-ultraviolet imagery at the focus of a large space telescope, with image formats up to 120 mm in diameter.
Variation in ejecta size with ejection velocity
NASA Technical Reports Server (NTRS)
Vickery, Ann M.
1987-01-01
The sizes and ranges of over 25,000 secondary craters around twelve large primaries on three different planets were measured and used to infer the size-velocity distribution of that portion of the primary crater ejecta that produced the secondaries. The ballistic equation for spherical bodies was used to convert the ranges to velocities, and the velocities and crater sizes were used in the appropriate Schmidt-Holsapple scaling relation of estimate ejecta sizes, and the velocity exponent was determined. The latter are generally between -1 and -13, with an average value of about -1.9. Problems with data collection made it impossible to determine a simple, unique relation between size and velocity.
NASA Astrophysics Data System (ADS)
Klee, H. W.; McDowell, M. W.
1986-02-01
A new lens design concept, based on the use of a zero (or near zero) power corrector, will be described. The logical development of the design, based on the work of Schmidt', Houghton' and others will be discussed and examples will be given of moderate field of view lenses with apertures ranging from f/0.35 to f/2. It will also be shown that the lens configuration is relatively insensitive to the aperture stop location and that for less demanding applications only very basic optical glass types need be used.
Almost all quantum channels are equidistant
NASA Astrophysics Data System (ADS)
Nechita, Ion; Puchała, Zbigniew; Pawela, Łukasz; Życzkowski, Karol
2018-05-01
In this work, we analyze properties of generic quantum channels in the case of large system size. We use random matrix theory and free probability to show that the distance between two independent random channels converges to a constant value as the dimension of the system grows larger. As a measure of the distance we use the diamond norm. In the case of a flat Hilbert-Schmidt distribution on quantum channels, we obtain that the distance converges to 1/2 +2/π , giving also an estimate for the maximum success probability for distinguishing the channels. We also consider the problem of distinguishing two random unitary rotations.
Coherence number as a discrete quantum resource
NASA Astrophysics Data System (ADS)
Chin, Seungbeom
2017-10-01
We introduce a discrete coherence monotone named the coherence number, which is a generalization of the coherence rank to mixed states. After defining the coherence number in a manner similar to that of the Schmidt number in entanglement theory, we present a necessary and sufficient condition of the coherence number for a coherent state to be converted to an entangled state of nonzero k concurrence (a member of the generalized concurrence family with 2 ≤k ≤d ). As an application of the coherence number to a practical quantum system, Grover's search algorithm of N items is considered. We show that the coherence number remains N and falls abruptly when the success probability of a searching process becomes maximal. This phenomenon motivates us to analyze the depletion pattern of Cc(N ) (the last member of the generalized coherence concurrence, nonzero when the coherence number is N ), which turns out to be an optimal resource for the process since it is completely consumed to finish the searching task. The generalization of the original Grover algorithm with arbitrary (mixed) initial states is also discussed, which reveals the boundary condition for the coherence to be monotonically decreasing under the process.
Mixing of a passive scalar in isotropic and sheared homogeneous turbulence
NASA Technical Reports Server (NTRS)
Shirani, E.; Ferziger, J. H.; Reynolds, W. C.
1981-01-01
In order to calculate the velocity and scalar fields, the three dimensional, time-dependent equations of motion and the diffusion equation were solved numerically. The following cases were treated: isotropic, homogeneous turbulence with decay of a passive scalar; and homogeneous turbulent shear flow with a passive scalar whose mean varies linearly in the spanwise direction. The solutions were obtained at relatively low Reynolds numbers so that all of the turbulent scales could be resolved without modeling. Turbulent statistics such as integral length scales, Taylor microscales, Kolmogorov length scale, one- and two-point correlations of velocity-velocity and velocity-scalar, turbulent Prandtl/Schmidt number, r.m.s. values of velocities, the scalar quantity and pressure, skewness, decay rates, and decay exponents were calculated. The results are compared with the available expermental results, and good agreement is obtained.
Numerical investigation of MHD flow with Soret and Dufour effect
NASA Astrophysics Data System (ADS)
Hayat, Tasawar; Nasir, Tehreem; Khan, Muhammad Ijaz; Alsaedi, Ahmed
2018-03-01
This paper describes the flow due to an exponentially curved surface subject to Soret and Dufour effects. Nonlinear velocity is considered. Exponentially curved stretchable sheet induced the flow. Fluid is electrical conducting through constant applied magnetic field. The governing flow expressions are reduced to ordinary ones and then tackled by numerical technique (Built-in-Shooting). Impacts of various flow variables on the dimensionless velocity, concentration and temperature fields are graphically presented and discussed in detail. Skin friction coefficient and Sherwood and Nusselt numbers are studied through graphs. Furthermore it is observed that Soret and Dufour variables regulate heat and mass transfer rates. It is also noteworthy that velocity decays for higher magnetic variable. Skin friction magnitude decays via curvature and magnetic variables. Also mass transfer gradient or rate of mass transport enhances for higher estimations of curvature parameter and Schmidt number.
Couette flow of an incompressible fluid in a porous channel with mass transfer
NASA Astrophysics Data System (ADS)
Niranjana, N.; Vidhya, M.; Govindarajan, A.
2018-04-01
The present discussion deals with the study of couette flow through a porous medium of a viscous incompressible fluid between two infinite horizontal parallel porous flat plates with heat and mass transfer. The stationary plate and the plate in uniform motion are subjected to transverse sinusoidal injection and uniform suction of the fluid. Due to this type of injection velocity, the flow becomes three dimensional. The analytical solutions of the nonlinear partial differential equations of this problem are obtained by using perturbation technique. Expressions for the velocity, temperature fields and the rate of heat and mass transfers are obtained. Effects of the following parameters Schmidt number (Sc), Modified Grashof number (Gm) on the velocity, temperature and concentration fields are obtained numerically and depicted through graphs. The rate of heat and mass transfer are also analyzed.
NASA Technical Reports Server (NTRS)
Warren, W. H., Jr.
1982-01-01
This catalog contains 1273 proven or probable Large Magellanic Cloud (LMC) members, as found on deep objective-prism plates taken with the Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory in Chile. The stars are generally brighter than about photographic magnitude 14. Approximate spectral types were determined by examination of the 580 A/mm objective-prism spectra; approximate 1975 positions were obtained by measuring relative to the 1975 coordinate grids on the Uppsala-Mount Stromlo Atlas of the LMC (Gascoigne and Westerlund 1961), and approximate photographic magnitudes were determined by averaging image density measures from the plates and image-diameter measures on the 'B' charts. The machine-readable version of the LMC survey catalog is described to enable users to read and process the tape file without problems or guesswork.
NASA Astrophysics Data System (ADS)
Yin, L.; Kopans-Johnson, C. R.; LeGrande, A. N.; Kelly, S.
2015-12-01
The isotopic ratio of 18O to 16O in seawater (2005ppm in ocean water is defined as 𝛿18Oseawater≡0 permil or 0‰) is a fundamental ocean tracer due to its distinct linear relationship with salinity(𝛿18O -S) from regional inland freshwater sources. As opposed to salinity alone, 𝛿18O distinguishes river runoff from sea-ice melt and traces ocean circulation pathways from coastal to open waters and surface to deep waters. Observations from the past 60 years of 𝛿18O seawater were compiled into a database by Schimdt et al. (1999), and subsequently used to calculate a 3-dimensional 1°x1° 𝛿18O global gridded dataset by LeGrande and Schmidt (2006). Although the Schmidt et al. (1999) Global Seawater Oxygen-18 Database (𝛿18Oobs) contains 25,514 measurements used to calculate the global gridded dataset, LeGrande and Schmidt (2006) point out that, "data coverage varies greatly from region to region," with seasonal variability creating biases in areas where sea ice is present. Python Pandas is used to automate the addition of 2,942 records to the Schmidt et al. (1999) Global Seawater Oxygen-18 Database (𝛿18Oobs), and examine the spatial and temporal distributions of 18O in the Arctic Ocean. 10 initial water masses are defined using spatial and temporal trends, clusters of observations, and Arctic surface circulation. Jackknife slope analysis of water mass 𝛿18O -S is used to determine anomalous data points and regional hydrology, resulting in 4 distinct Arctic water masses. These techniques are used to improve the gridded 𝛿18Oseawater dataset by distinguishing unique water masses, and accounting for seasonal variability of complex high latitude areas.
The Wide-Field Infrared Survey Explorer (WISE): Mission Description and Initial On-Orbit Performance
NASA Technical Reports Server (NTRS)
Wright, Edward L.; Eisenhardt, Peter R. M.; Mainzer, Amy; Ressler, Michael E.; Cutri, Roc M.; Jarrett, Thomas; Kirkpatrick, J. Davy; Padgett, Deborah; McMillan, Robert S.; Skrutskie,Michael;
2010-01-01
The all sky surveys done by the Palomar Observatory Schmidt, the European Southern Observatory Schmidt, and the United Kingdom Schmidt, the InfraRed Astronomical Satellite and the 2 Micron All Sky Survey have proven to be extremely useful tools for astronomy with value that lasts for decades. The Wide-field Infrared Survey Explorer is mapping the whole sky following its launch on 14 December 2009. WISE began surveying the sky on 14 Jan 2010 and completed its first full coverage of the sky on July 17. The survey will continue to cover the sky a second time until the cryogen is exhausted (anticipated in November 2010). WISE is achieving 5 sigma point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in bands centered at wavelengths of 3.4, 4.6, 12 and 22 micrometers. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background. The angular resolution is 6.1", 6.4", 6.5" and 12.0" at 3.4, 4.6, 12 and 22 micrometers, and the astrometric precision for high SNR sources is better than 0.15".
Kataev, Boris M.; Liang, Hongbin; Kavanaugh, David H.
2012-01-01
Abstract Five new species of the genus Chydaeus Chaudoir, 1854 are described from China: Chydaeus fugongensis sp. n. (Shibali, Fugong County, Yunnan Province), Chydaeus gutangensis sp. n. (Gutang, Medog County, Xizang Autonomous Region [Tibet]), Chydaeus hanmiensis sp. n. (Hanmi, Medog County, Xizang Autonomous Region [Tibet]), Chydaeus asetosus sp. n. (NE of Fugong, Yunnan Province), and Chydaeus baoshanensis sp. n. (N of Baoshan, Yunnan Province). Taxonomic and faunistic notes on eleven other species occurring in Xizang and Yunnan are also provided. Chydaeus shunichii Ito, 2006 is re-described, based on specimens from Lushui County, Yunnan. Chydaeus kumei Ito, 1992 is treated as a subspecies of Chydaeus andrewesi Schauberger, 1932 [NEW STATUS]. The taxonomic status of Chydaeus guangxiensis Ito, 2006 is discussed. The following taxa are recorded from China for the first time: Chydaeus obtusicollis Schauberger, 1932 (Xizang and Yunnan), Chydaeus malaisei Kataev & Schmidt, 2006 (Yunnan), Chydaeus semenowi (Tschitschérine, 1899) (Xizang and Yunnan), Chydaeus andrewesi andrewesi Schauberger, 1932 (Xizang and Yunnan), Chydaeus andrewesi kumei Ito (Yunnan), Chydaeus bedeli interjectus Kataev & Schmidt, 2002 (Xizang), and Chydaeus bedeli vietnamensis Kataev & Schmidt, 2002 (Yunnan). PMID:22423195
SMV⊥: Simplex of maximal volume based upon the Gram-Schmidt process
NASA Astrophysics Data System (ADS)
Salazar-Vazquez, Jairo; Mendez-Vazquez, Andres
2015-10-01
In recent years, different algorithms for Hyperspectral Image (HI) analysis have been introduced. The high spectral resolution of these images allows to develop different algorithms for target detection, material mapping, and material identification for applications in Agriculture, Security and Defense, Industry, etc. Therefore, from the computer science's point of view, there is fertile field of research for improving and developing algorithms in HI analysis. In some applications, the spectral pixels of a HI can be classified using laboratory spectral signatures. Nevertheless, for many others, there is no enough available prior information or spectral signatures, making any analysis a difficult task. One of the most popular algorithms for the HI analysis is the N-FINDR because it is easy to understand and provides a way to unmix the original HI in the respective material compositions. The N-FINDR is computationally expensive and its performance depends on a random initialization process. This paper proposes a novel idea to reduce the complexity of the N-FINDR by implementing a bottom-up approach based in an observation from linear algebra and the use of the Gram-Schmidt process. Therefore, the Simplex of Maximal Volume Perpendicular (SMV⊥) algorithm is proposed for fast endmember extraction in hyperspectral imagery. This novel algorithm has complexity O(n) with respect to the number of pixels. In addition, the evidence shows that SMV⊥ calculates a bigger volume, and has lower computational time complexity than other poular algorithms on synthetic and real scenarios.
Interpreting the sub-linear Kennicutt-Schmidt relationship: the case for diffuse molecular gas
NASA Astrophysics Data System (ADS)
Shetty, Rahul; Clark, Paul C.; Klessen, Ralf S.
2014-08-01
Recent statistical analysis of two extragalactic observational surveys strongly indicate a sub-linear Kennicutt-Schmidt (KS) relationship between the star formation rate (ΣSFR) and molecular gas surface density (Σmol). Here, we consider the consequences of these results in the context of common assumptions, as well as observational support for a linear relationship between ΣSFR and the surface density of dense gas. If the CO traced gas depletion time (τ_dep^CO) is constant, and if CO only traces star-forming giant molecular clouds (GMCs), then the physical properties of each GMC must vary, such as the volume densities or star formation rates. Another possibility is that the conversion between CO luminosity and Σmol, the XCO factor, differs from cloud-to-cloud. A more straightforward explanation is that CO permeates the hierarchical interstellar medium, including the filaments and lower density regions within which GMCs are embedded. A number of independent observational results support this description, with the diffuse gas comprising at least 30 per cent of the total molecular content. The CO bright diffuse gas can explain the sub-linear KS relationship, and consequently leads to an increasing τ_dep^CO with Σmol. If ΣSFR linearly correlates with the dense gas surface density, a sub-linear KS relationship indicates that the fraction of diffuse gas fdiff grows with Σmol. In galaxies where Σmol falls towards the outer disc, this description suggests that fdiff also decreases radially.
NASA Technical Reports Server (NTRS)
Miller, T. L.
1986-01-01
Numerical modeling has been performed of the fluid dynamics in a prototypical physical vapor transport crystal growing situation. Cases with and without gravity have been computed. Dependence of the flows upon the dimensionless parameters aspect ratio and Peclet, Rayleigh, and Schmidt numbers is demonstrated to a greater extent than in previous works. Most notably, it is shown that the effects of thermally-induced buoyant convection upon the mass flux on the growth interface crucially depend upon the temperature boundary conditions on the sidewall (e.g., whether adiabatic or of a fixed profile, and in the latter case the results depend upon the shape of the profile assumed).
Similar solutions of double-diffusive dissipative layers along free surfaces
NASA Astrophysics Data System (ADS)
Napolitano, L. G.; Viviani, A.; Savino, R.
1990-10-01
Free convection due to buoyant forces (natural convection) and surface tension gradients (Marangoni convection) generated by temperature and concentration gradients is discussed together with the formation of double-diffusive boundary layers along liquid-gas interfaces. Similarity solutions for each class of free convection are derived and the resulting nonlinear two-point problems are solved numerically using the quasi-linearization method. Velocity, temperature, concentration profiles, interfacial velocity, heat and mass transfer bulk coefficients for various Prandtl and Schmidt numbers, and different values of the similarity parameters are determined. The convective flows are of particular interest because they are considered to influence the processes of crystal growth, both on earth and in a microgravity environment.
Widely tunable single photon source with high purity at telecom wavelength.
Jin, Rui-Bo; Shimizu, Ryosuke; Wakui, Kentaro; Benichi, Hugo; Sasaki, Masahide
2013-05-06
We theoretically and experimentally investigate the spectral tunability and purity of photon pairs generated from spontaneous parametric down conversion in periodically poled KTiOPO(4) crystal with group-velocity matching condition. The numerical simulation predicts that the spectral purity can be kept higher than 0.81 when the wavelength is tuned from 1460 nm to 1675 nm, which covers the S-, C-, L-, and U-band in telecommunication wavelengths. We also experimentally measured the joint spectral intensity at 1565 nm, 1584 nm and 1565 nm, yielding Schmidt numbers of 1.01, 1.02 and 1.04, respectively. Such a photon source is useful for quantum information and communication systems.
Structure of turbulent non-premixed flames modeled with two-step chemistry
NASA Technical Reports Server (NTRS)
Chen, J. H.; Mahalingam, S.; Puri, I. K.; Vervisch, L.
1992-01-01
Direct numerical simulations of turbulent diffusion flames modeled with finite-rate, two-step chemistry, A + B yields I, A + I yields P, were carried out. A detailed analysis of the turbulent flame structure reveals the complex nature of the penetration of various reactive species across two reaction zones in mixture fraction space. Due to this two zone structure, these flames were found to be robust, resisting extinction over the parameter ranges investigated. As in single-step computations, mixture fraction dissipation rate and the mixture fraction were found to be statistically correlated. Simulations involving unequal molecular diffusivities suggest that the small scale mixing process and, hence, the turbulent flame structure is sensitive to the Schmidt number.
A deep survey for Galactic Wolf-Rayet stars. I - Motivation, search technique, and first results
NASA Technical Reports Server (NTRS)
Shara, Michael M.; Smith, Lindsey F.; Potter, Michael; Moffat, Anthony F. J.
1991-01-01
Results are presented from a survey of large areas of the southern Milky Way for Wolf-Rayet (WR) stars to 17-18th magnitude, carried out using direct narrowband and broadband Schmidt plates. Thirteen new WR stars were detected in an about 40-deg-sq region in Carina, where 24 WR stars were already known; the new stars were found to be significantly redder, fainter, and farther away than the known stars. Of the new WR stars, 11 are of subtype WN, and two are WC, compared to the 17 WN and seven WC stars among the previously known WR stars in the same area.
Formation Stellaire Aux Échelles Des Galaxies
NASA Astrophysics Data System (ADS)
Boissier, S.
2012-12-01
Star Formation is at the very core of the evolution of galaxies. From their gas reservoir (filled by infall or fusions), stars form at the "Star Formation Rate" (SFR), with an enormous impact on many aspects of the evolution of galaxies. This HDR presents first the formalism concerning star formation (SFR, IMF), some theoretical suggestions on physical processes that may affect star formation on various galactic scales, and the methods used to determine the SFR from observations. A large part is dedicated to the "Star Formation Laws" (e.g. Schmidt law) on various scales (local, radial, and global law). Finally, the last part concerns the largest scales (evolution of the "cosmic" SFR and effect of the environment).
The Next Century Astrophysics Program
NASA Technical Reports Server (NTRS)
Swanson, Paul N.
1991-01-01
The Astrophysics Division within the NASA Office of Space Science and Applications (OSSA) has defined a set of major and moderate missions that are presently under study for flight sometime within the next 20 years. These programs include the: Advanced X Ray Astrophysics Facility; X Ray Schmidt Telescope; Nuclear Astrophysics Experiment; Hard X Ray Imaging Facility; Very High Throughput Facility; Gamma Ray Spectroscopy Observatory; Hubble Space Telescope; Lunar Transit Telescope; Astrometric Interferometer Mission; Next Generation Space Telescope; Imaging Optical Interferometer; Far Ultraviolet Spectroscopic Explorer; Gravity Probe B; Laser Gravity Wave Observatory in Space; Stratospheric Observatory for Infrared Astronomy; Space Infrared Telescope Facility; Submillimeter Intermediate Mission; Large Deployable Reflector; Submillimeter Interferometer; and Next Generation Orbiting Very Long Baseline Interferometer.
Lee wave breaking region: the map of instability development scenarios
NASA Astrophysics Data System (ADS)
Yakovenko, S. N.
2017-10-01
Numerical study of a stably stratified flow above the two-dimensional cosine-shaped obstacle has been performed by DNS and LES. These methods were implemented to solve the three-dimensional Navier-Stokes equations in the Boussinesq approximation, together with by the scalar diffusion equation. The results of scanning in the wide ranges of physical parameters (Reynolds and Prandtl/Schmidt numbers relating to laboratory experiment cases and atmospheric or oceanic situations) are presented for instability and turbulence development scenarios in the overturning internal lee waves. The latter is generated by the obstacle in a flow with the constant inflow values of velocity and stable density gradient. Evolution of lee-wave breaking is explored by visualization of velocity and scalar (density) fields, and the analysis of spectra. Based on the numerical simulation results, the power-law dependence on Reynolds number is demonstrated for the wavelength of the most unstable perturbation.
A historical analysis of natural gas demand
NASA Astrophysics Data System (ADS)
Dalbec, Nathan Richard
This thesis analyzes demand in the US energy market for natural gas, oil, and coal over the period of 1918-2013 and examines their price relationship over the period of 2007-2013. Diagnostic tests for time series were used; Augmented Dickey-Fuller, Kwiatkowski-Phillips-Schmidt-Shin, Johansen cointegration, Granger Causality and weak exogeneity tests. Directed acyclic graphs were used as a complimentary test for endogeneity. Due to the varied results in determining endogeneity, a seemingly unrelated regression model was used which assumes all right hand side variables in the three demand equations were exogenous. A number of factors were significant in determining demand for natural gas including its own price, lagged demand, a number of structural break dummies, and trend, while oil indicate some substitutability with natural gas. An error correction model was used to examine the price relationships. Natural gas price was found not to have a significant cointegrating vector.
NASA Technical Reports Server (NTRS)
Kandula, M.; Haddad, G. F.; Chen, R.-H.
2006-01-01
Three-dimensional Navier-Stokes computational fluid dynamics (CFD) analysis has been performed in an effort to determine thermal boundary layer correction factors for circular convective heat flux gauges (such as Schmidt-Boelter and plug type)mounted flush in a flat plate subjected to a stepwise surface temperature discontinuity. Turbulent flow solutions with temperature-dependent properties are obtained for a free stream Reynolds number of 1E6, and freestream Mach numbers of 2 and 4. The effect of gauge diameter and the plate surface temperature have been investigated. The 3-D CFD results for the heat flux correction factors are compared to quasi-21) results deduced from constant property integral solutions and also 2-D CFD analysis with both constant and variable properties. The role of three-dimensionality and of property variations on the heat flux correction factors has been demonstrated.
Morphological instability of a thermophoretically growing deposit
NASA Technical Reports Server (NTRS)
Castillo, Jose L.; Garcia-Ybarra, Pedro L.; Rosner, Daniel E.
1992-01-01
The stability of the planar interface of a structureless solid growing from a depositing component dilute in a carrier fluid is studied when the main solute transport mechanism is thermal (Soret) diffusion. A linear stability analysis, carried out in the limit of low growth Peclet number, leads to a dispersion relation which shows that the planar front is unstable either when the thermal diffusion factor of the condensing component is positive and the latent heat release is small or when the thermal diffusion factor is negative and the solid grows over a thermally-insulating substrate. Furthermore, the influence of interfacial energy effects and constitutional supersaturation in the vicinity of the moving interface is analyzed in the limit of very small Schmidt numbers (small solute Fickian diffusion). The analysis is relevant to physical vapor deposition of very massive species on cold surfaces, as in recent experiments of organic solid film growth under microgravity conditions.
The Zwicky Transient Facility Camera
NASA Astrophysics Data System (ADS)
Dekany, Richard; Smith, Roger M.; Belicki, Justin; Delacroix, Alexandre; Duggan, Gina; Feeney, Michael; Hale, David; Kaye, Stephen; Milburn, Jennifer; Murphy, Patrick; Porter, Michael; Reiley, Daniel J.; Riddle, Reed L.; Rodriguez, Hector; Bellm, Eric C.
2016-08-01
The Zwicky Transient Facility Camera (ZTFC) is a key element of the ZTF Observing System, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the Zwicky Transient Facility. The ZTFC consists of a compact cryostat with large vacuum window protecting a mosaic of 16 large, wafer-scale science CCDs and 4 smaller guide/focus CCDs, a sophisticated vacuum interface board which carries data as electrical signals out of the cryostat, an electromechanical window frame for securing externally inserted optical filter selections, and associated cryo-thermal/vacuum system support elements. The ZTFC provides an instantaneous 47 deg2 field of view, limited by primary mirror vignetting in its Schmidt telescope prime focus configuration. We report here on the design and performance of the ZTF CCD camera cryostat and report results from extensive Joule-Thompson cryocooler tests that may be of broad interest to the instrumentation community.
NASA Astrophysics Data System (ADS)
Katul, Gabriel; Liu, Heping
2017-04-01
In his 1881 acceptance letter of the Rumford Medal, Gibbs declared that "One of the principal objects of theoretical research is to find the point of view from which the subject appears in the greatest simplicity". Guided by this quotation, the subject of evaporation into the atmosphere from rough surfaces by turbulence offered in a 1965 study by Brutsaert is re-examined. Brutsaert proposed a model that predicted mean evaporation rate E from rough surfaces to scale with the 3/4 power-law of the friction velocity (u∗) and the square-root of molecular diffusivity (Dm) for water vapor. This result was supported by a large corpus of experiments and spawned a number of studies on inter-facial transfer of scalars, evaporation from porous media at single and multiple pore scales, bulk evaporation from bare soil surfaces, as well as isotopic fractionation in hydrological applications. It also correctly foreshadowed the much discussed 1/4 'universal' scaling of liquid transfer coefficients of sparingly soluble gases in air-sea exchange studies. In arriving at these results, a number of assumptions were made regarding the surface renewal rate describing the contact durations between eddies and the evaporating surface, the diffusional mass process from the surface into eddies, and the cascade of turbulent kinetic energy sustaining the eddy renewal process itself. The anzats explored here is that E ˜√Dm-u∗3/4 is a direct outcome of the Kolmogorov scaling for inertial subrange eddies modified to include viscous-cutoff thereby by-passing the need for a surface renewal assumption. It is demonstrated that Brutsaert's model for E may be more general than its original derivation assumed. Extensions to canopy surfaces as well as other scalars with different molecular Schmidt numbers are also featured.
Global variation of the dust-to-gas ratio in evolving protoplanetary discs
NASA Astrophysics Data System (ADS)
Hughes, Anna L. H.; Armitage, Philip J.
2012-06-01
Recent theories suggest planetesimal formation via streaming and/or gravitational instabilities may be triggered by localized enhancements in the dust-to-gas ratio, and one hypothesis is that sufficient enhancements may be produced in the pile-up of small solid particles inspiralling under aerodynamic drag from the large mass reservoir in the outer disc. Studies of particle pile-up in static gas discs have provided partial support for this hypothesis. Here, we study the radial and temporal evolution of the dust-to-gas ratio in turbulent discs that evolve under the action of viscosity and photoevaporation. We find that particle pile-ups do not generically occur within evolving discs, particularly if the introduction of large grains is restricted to the inner, dense regions of a disc. Instead, radial drift results in depletion of solids from the outer disc, while the inner disc maintains a dust-to-gas ratio that is within a factor of ˜2 of the initial value. We attribute this result to the short time-scales for turbulent diffusion and radial advection (with the mean gas flow) in the inner disc. We show that the qualitative evolution of the dust-to-gas ratio depends only weakly upon the parameters of the disc model (the disc mass, size, viscosity and value of the Schmidt number), and discuss the implications for planetesimal formation via collective instabilities. Our results suggest that in discs where there is a significant level of midplane turbulence and accretion, planetesimal formation would need to be possible in the absence of large-scale enhancements. Instead, trapping and concentration of particles within local turbulent structures may be required as a first stage of planetesimal formation.
NASA Technical Reports Server (NTRS)
Rosen, I. G.
1988-01-01
An approximation and convergence theory was developed for Galerkin approximations to infinite dimensional operator Riccati differential equations formulated in the space of Hilbert-Schmidt operators on a separable Hilbert space. The Riccati equation was treated as a nonlinear evolution equation with dynamics described by a nonlinear monotone perturbation of a strongly coercive linear operator. A generic approximation result was proven for quasi-autonomous nonlinear evolution system involving accretive operators which was then used to demonstrate the Hilbert-Schmidt norm convergence of Galerkin approximations to the solution of the Riccati equation. The application of the results was illustrated in the context of a linear quadratic optimal control problem for a one dimensional heat equation.
A priori analysis of differential diffusion for model development for scale-resolving simulations
NASA Astrophysics Data System (ADS)
Hunger, Franziska; Dietzsch, Felix; Gauding, Michael; Hasse, Christian
2018-01-01
The present study analyzes differential diffusion and the mechanisms responsible for it with regard to the turbulent/nonturbulent interface (TNTI) with special focus on model development for scale-resolving simulations. In order to analyze differences between resolved and subfilter phenomena, direct numerical simulation (DNS) data are compared with explicitly filtered data. The DNS database stems from a temporally evolving turbulent plane jet transporting two passive scalars with Schmidt numbers of unity and 0.25 presented by Hunger et al. [F. Hunger et al., J. Fluid Mech. 802, R5 (2016), 10.1017/jfm.2016.471]. The objective of this research is twofold: (i) to compare the position of the turbulent-nonturbulent interface between the original DNS data and the filtered data and (ii) to analyze differential diffusion and the impact of the TNTI with regard to scale resolution in the filtered DNS data. For the latter, differential diffusion quantities are studied, clearly showing the decrease of differential diffusion at the resolved scales with increasing filter width. A transport equation for the scalar differences is evaluated. Finally, the existence of large scalar gradients, gradient alignment, and the diffusive fluxes being the physical mechanisms responsible for the separation of the two scalars are compared between the resolved and subfilter scales.
Design and synthesis of chalcone derivatives as potential non-purine xanthine oxidase inhibitors.
Bui, Trung Huu; Nguyen, Nhan Trung; Dang, Phu Hoang; Nguyen, Hai Xuan; Nguyen, Mai Thanh Thi
2016-01-01
Based on some previous research, the chalcone derivatives exhibited potent xanthine oxidase inhibitory activity, e.g. sappanchalcone ( 7 ), with IC 50 value of 3.9 μM, was isolated from Caesalpinia sappan . Therefore, objectives of this research are design and synthesis of 7 and other chalcone derivatives by Claisen-Schmidt condensation and then evaluate their XO inhibitory activity. Fifteen chalcone derivatives were synthesized by Claisen-Schmidt condensation, and were evaluated for XO inhibitory activity. Nine out of 15 synthetic chalcones showed inhibitory activity ( 3 ; 5 - 8 ; 10 - 13 ). Sappanchalcone derivatives ( 11 ) (IC 50 , 2.5 μM) and a novel chalcone ( 13 ) (IC 50 , 2.4 μM) displayed strong xanthine oxidase inhibitory activity that is comparable to allopurinol (IC 50 , 2.5 μM). The structure-activity relationship of these chalcone derivatives was also presented. It is the first research on synthesis sappanchalcone ( 7 ) by Claisen-Schmidt condensation. The overall yield of this procedure was 6.6 %, higher than that of reported procedure (4 %). Design, synthesis, and evaluation of chalcone derivatives were carried out. This result suggests that the chalcone derivative can be used as potential non-purine XO inhibitors.Graphical abstractThe chalcone derivatives as potential non-purine xanthine oxidase inhibitors.
Roger Hayward and the Invention of the Two-Mirror Schmidt
NASA Astrophysics Data System (ADS)
Bell, T. E.
2005-12-01
Roger Hayward (1899-1979), now virtually unknown, was a multitalented architect, scientific illustrator, and optical inventor. Remembered primarily for illustrating Scientific American magazine's Amateur Scientist column between 1949 and 1974, he also illustrated more than a dozen textbooks in optics, physics, geology, oceanography, and chemistry, several of which became classics in their fields. He designed façades with astronomical themes for major buildings in Los Angeles, California, and sculpted mammoth, realistic models of the moon for Griffith Observatory, Adler Planetarium, and Disneyland. Throughout his life, he recreationally painted watercolors and oils that at least one critic likened to the work of John Singer Sargent. Hayward is least known as an optical designer, yet he made significant contributions to the DU spectrophotometer that established the multimillion-dollar company Beckman Instruments. During the pre-radar days of World War II at Mount Wilson Observatory, Hayward invented a classified Cassegrain version of the Schmidt telescope especially adapted for nighttime infrared aerial photography, plus extraordinarily simple machines that allowed inexperienced soldiers to grind, polish, and test accurate aspheric Schmidt correcting plates at speeds compatible with mass production - and later received U.S. patents for them all. This paper, drawn in part from unpublished letters between Hayward and Albert G. Ingalls, will feature little-known images of Hayward's work.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gheorghiu, Vlad; Yu Li; Cohen, Scott M.
We investigate the conditions under which a set S of pure bipartite quantum states on a DxD system can be locally cloned deterministically by separable operations, when at least one of the states is full Schmidt rank. We allow for the possibility of cloning using a resource state that is less than maximally entangled. Our results include that: (i) all states in S must be full Schmidt rank and equally entangled under the G-concurrence measure, and (ii) the set S can be extended to a larger clonable set generated by a finite group G of order |G|=N, the number ofmore » states in the larger set. It is then shown that any local cloning apparatus is capable of cloning a number of states that divides D exactly. We provide a complete solution for two central problems in local cloning, giving necessary and sufficient conditions for (i) when a set of maximally entangled states can be locally cloned, valid for all D; and (ii) local cloning of entangled qubit states with nonvanishing entanglement. In both of these cases, we show that a maximally entangled resource is necessary and sufficient, and the states must be related to each other by local unitary 'shift' operations. These shifts are determined by the group structure, so need not be simple cyclic permutations. Assuming this shifted form and partially entangled states, then in D=3 we show that a maximally entangled resource is again necessary and sufficient, while for higher-dimensional systems, we find that the resource state must be strictly more entangled than the states in S. All of our necessary conditions for separable operations are also necessary conditions for local operations and classical communication (LOCC), since the latter is a proper subset of the former. In fact, all our results hold for LOCC, as our sufficient conditions are demonstrated for LOCC, directly.« less
Use of argon to measure gas exchange in turbulent mountain streams
NASA Astrophysics Data System (ADS)
Hall, Robert O., Jr.; Madinger, Hilary L.
2018-05-01
Gas exchange is a parameter needed in stream metabolism and trace gas emissions models. One way to estimate gas exchange is via measuring the decline of added tracer gases such as sulfur hexafluoride (SF6). Estimates of oxygen (O2) gas exchange derived from SF6 additions require scaling via Schmidt number (Sc) ratio, but this scaling is uncertain under conditions of high gas exchange via bubbles because scaling depends on gas solubility as well as Sc. Because argon (Ar) and O2 have nearly identical Schmidt numbers and solubility, Ar may be a useful tracer gas for estimating stream O2 exchange. Here we compared rates of gas exchange measured via Ar and SF6 for turbulent mountain streams in Wyoming, USA. We measured Ar as the ratio of Ar : N2 using a membrane inlet mass spectrometer (MIMS). Normalizing to N2 confers higher precision than simply measuring [Ar] alone. We consistently enriched streams with Ar from 1 to 18 % of ambient Ar concentration and could estimate gas exchange rate using an exponential decline model. The mean ratio of gas exchange of Ar relative to SF6 was 1.8 (credible interval 1.1 to 2.5) compared to the theoretical estimate 1.35, showing that using SF6 would have underestimated exchange of Ar. Steep streams (slopes 11-12 %) had high rates of gas exchange velocity normalized to Sc = 600 (k600, 57-210 m d-1), and slope strongly predicted variation in k600 among all streams. We suggest that Ar is a useful tracer because it is easily measured, requires no scaling assumptions to estimate rates of O2 exchange, and is not an intense greenhouse gas as is SF6. We caution that scaling from rates of either Ar or SF6 gas exchange to CO2 is uncertain due to solubility effects in conditions of bubble-mediated gas transfer.
NASA Astrophysics Data System (ADS)
Hughson, K.; Russell, C.; Schmidt, B. E.; Chilton, H.; Scully, J. E. C.; Castillo, J. C.; Combe, J. P.; Ammannito, E.; Sizemore, H.; Platz, T.; Byrne, S.; Nathues, A.; Raymond, C. A.
2016-12-01
NASA's Dawn spacecraft arrived at Ceres on March 6, 2015, and has been studying the dwarf planet through a series of successively lower orbits, obtaining morphological and topographical image, mineralogical, elemental composition, and gravity data (Russell et al., 2016). Images taken by Dawn's Framing Camera show a multitude of flow features that were broadly interpreted as ground ice related structures either similar to ice cored/ice cemented flows (as seen on Earth and Mars), long run-out landslides, or fluidized ejecta (as seen on Mars) by Schmidt et al. (2016a and 2016b) and Buczkowski et al. (2016). The aforementioned ice cored/ice cemented-like flows are present only at high latitudes. Results from Dawn's Gamma Ray and Neutron Detector (GRaND) indicate a shallow ice table on Ceres above 45-50°N/S, which supports the interpretation that these flows are ice-rich (Prettyman et al., 2016). A near coincident spectral detection of H2O ice with one of these ice cored/ice cemented-like flows in Oxo crater by Dawn's Visual and Infrared spectrometer (VIR) further bolsters this claim (Combe et al., 2016). We use aggregate spatial and physical properties of these ice attributed cerean flows, such as flow orientation, inclination, preference for north or south facing slopes, drop height to run-out length ratio, geographical location, and areal number density to better understand the rheology and distribution of ground ice in Ceres' uppermost layer. By combining these data with local spectroscopic, global elemental abundance, experimentally derived physical properties of cerean analogue material, and other morphological information (such as the morphologies of flow hosting craters) we intend to further test the ground ice hypothesis for the formation of these flows and constrain the global distribution of near surface ground ice on Ceres to a higher fidelity than what would be possible using GRaND and VIR observations alone. References: Buczkowski et al., (2016) Science, AcceptedCombe, J-P., et al. (2016) Science, AcceptedPrettyman, T. H., et al. (2016) LPSC XVII, Abstract #2228 Russell, et al. (2016) Science, AcceptedSchmidt, B. E., et al. (2016a) LPSC XVII, Abstract #2677 Schmidt, B. E., et al. (2016b), Nature Geoscience, In Review
A systematic revision of Baconia Lewis (Coleoptera, Histeridae, Exosternini).
Caterino, Michael S; Tishechkin, Alexey K
2013-01-01
Here we present a complete revision of the species of Baconia. Up until now there have been 27 species assigned to the genus (Mazur, 2011), in two subgenera (Binhister Cooman and Baconia s. str.), with species in the Neotropical, Nearctic, Palaearctic, and Oriental regions. We recognize all these species as valid and correctly assigned to the genus, and redescribe all of them. We synonymize Binhister, previously used for a polyphyletic assemblage of species with varied relationships in the genus. We move four species into Baconia from other genera, and describe 85 species as new, bringing the total for the genus to 116 species. We divide these into 12 informal species groups, leaving 13 species unplaced to group. We present keys and diagnoses for all species, as well as habitus photos and illustrations of male genitalia for nearly all. The genus now contains the following species and species groups: Baconia loricata group [Baconia loricata Lewis, 1885, B. patula Lewis, 1885, Baconia gounellei (Marseul, 1887a), Baconia jubaris (Lewis, 1901), Baconia festiva (Lewis, 1891), Baconia foliosoma sp. n., Baconia sapphirina sp. n., Baconia furtiva sp. n., Baconia pernix sp. n., Baconia applanatis sp. n., Baconia disciformis sp. n., Baconia nebulosa sp. n., Baconia brunnea sp. n.], Baconia godmani group [Baconia godmani (Lewis, 1888), Baconia venusta (J. E. LeConte, 1845), Baconia riehli (Marseul, 1862), comb. n., Baconia scintillans sp. n., Baconia isthmia sp. n., Baconia rossi sp. n., Baconia navarretei sp. n., Baconia maculata sp. n., Baconia deliberata sp. n., Baconia excelsa sp. n., Baconia violacea (Marseul, 1853), Baconia varicolor (Marseul, 1887b), Baconia dives (Marseul, 1862), Baconia eximia (Lewis, 1888), Baconia splendida sp. n., Baconia jacinta sp. n., Baconia prasina sp. n., Baconia opulenta sp. n., Baconia illustris (Lewis, 1900), Baconia choaspites (Lewis, 1901), Baconia lewisi Mazur, 1984], Baconia salobrus group [Baconia salobrus (Marseul, 1887b), Baconia turgifrons sp. n., Baconia crassa sp. n., Baconia anthracina sp. n., Baconia emarginata sp. n., Baconia obsoleta sp. n.], Baconia ruficauda group [Baconia ruficauda sp. n., Baconia repens sp. n.], Baconia angusta group [Baconia angusta Schmidt, 1893a, Baconia incognita sp. n., Baconia guartela sp. n., Baconia bullifrons sp. n., Baconia cavei sp. n., Baconia subtilis sp. n., Baconia dentipes sp. n., Baconia rubripennis sp. n., Baconia lunatifrons sp. n.], Baconia aeneomicans group [Baconia aeneomicans (Horn, 1873), Baconia pulchella sp. n., Baconia quercea sp. n., Baconia stephani sp. n., Baconia irinae sp. n., Baconia fornix sp. n., Baconia slipinskii Mazur, 1981, Baconia submetallica sp. n., Baconia diminua sp. n., Baconia rufescens sp. n., Baconia punctiventer sp. n., Baconia aulaea sp. n., Baconia mustax sp. n., Baconia plebeia sp. n., Baconia castanea sp. n., Baconia lescheni sp. n., Baconia oblonga sp. n., Baconia animata sp. n., Baconia teredina sp. n., Baconia chujoi (Cooman, 1941), Baconia barbarus (Cooman, 1934), Baconia reposita sp. n., Baconia kubani sp. n., Baconia wallacea sp. n., Baconia bigemina sp. n., Baconia adebratti sp. n., Baconia silvestris sp. n.], Baconia cylindrica group [Baconia cylindrica sp. n., Baconia chatzimanolisi sp. n.], Baconia gibbifer group [Baconia gibbifer sp. n., B. piluliformis sp. n., Baconia maquipucunae sp. n., Baconia tenuipes sp. n., Baconia tuberculifer sp. n., Baconia globosa sp. n.], Baconia insolita group [Baconia insolita (Schmidt, 1893a), comb. n., Baconia burmeisteri (Marseul, 1870), Baconia tricolor sp. n., Baconia pilicauda sp. n.], Baconia riouka group [Baconia riouka (Marseul, 1861), Baconia azuripennis sp. n.], Baconia famelica group [Baconia famelica sp. n., Baconia grossii sp. n., Baconia redemptor sp. n., Baconia fortis sp. n., Baconia longipes sp. n., Baconia katieae sp. n., Baconia cavifrons (Lewis, 1893), comb. n., Baconia haeterioides sp. n.], Baconia micans group [Baconia micans (Schmidt, 1889a), Baconia carinifrons sp. n., Baconia fulgida (Schmidt, 1889c)], Baconia incertae sedis [Baconia chilense (Redtenbacher, 1867), Baconia glauca (Marseul, 1884), Baconia coerulea (Bickhardt, 1917), Baconia angulifrons sp. n., Baconia sanguinea sp. n., Baconia viridimicans (Schmidt, 1893b), Baconia nayarita sp. n., Baconia viridis sp. n., Baconia purpurata sp. n., Baconia aenea sp. n., Baconia clemens sp. n., Baconia leivasi sp. n., Baconia atricolor sp. n.]. We designate lectotypes for the following species: Baconia loricata Lewis, 1885,Phelister gounellei Marseul, 1887, Baconia jubaris Lewis, 1901, Baconia festiva Lewis, 1891, Platysoma venustum J.E. LeConte, 1845, Phelister riehli Marseul, 1862, Phelister violaceus Marseul, 1853, Phelister varicolor Marseul, 1887b, Phelister illustris Lewis, 1900, Baconia choaspites Lewis, 1901, Epierus festivus Lewis, 1898, Phelister salobrus Marseul, 1887, Baconia angusta Schmidt, 1893a, Phelister insolitus Schmidt, 1893a, Pachycraerus burmeisteri Marseul, 1870, Phelister riouka Marseul, 1861, Homalopygus cavifrons Lewis, 1893, Phelister micans Schmidt, 1889a, Phelister coeruleus Bickhardt, 1917, and Phelister viridimicans Schmidt, 1893b. We designate neotypes for Baconia patula Lewis, 1885 and Hister aeneomicans Horn, 1873, whose type specimens are lost.
A systematic revision of Baconia Lewis (Coleoptera, Histeridae, Exosternini)
Caterino, Michael S.; Tishechkin, Alexey K.
2013-01-01
Abstract Here we present a complete revision of the species of Baconia. Up until now there have been 27 species assigned to the genus (Mazur, 2011), in two subgenera (Binhister Cooman and Baconia s. str.), with species in the Neotropical, Nearctic, Palaearctic, and Oriental regions. We recognize all these species as valid and correctly assigned to the genus, and redescribe all of them. We synonymize Binhister, previously used for a polyphyletic assemblage of species with varied relationships in the genus. We move four species into Baconia from other genera, and describe 85 species as new, bringing the total for the genus to 116 species. We divide these into 12 informal species groups, leaving 13 species unplaced to group. We present keys and diagnoses for all species, as well as habitus photos and illustrations of male genitalia for nearly all. The genus now contains the following species and species groups: Baconia loricata group [Baconia loricata Lewis, 1885, B. patula Lewis, 1885, Baconia gounellei (Marseul, 1887a), Baconia jubaris (Lewis, 1901), Baconia festiva (Lewis, 1891), Baconia foliosoma sp. n., Baconia sapphirina sp. n., Baconia furtiva sp. n., Baconia pernix sp. n., Baconia applanatis sp. n., Baconia disciformis sp. n., Baconia nebulosa sp. n., Baconia brunnea sp. n.], Baconia godmani group [Baconia godmani (Lewis, 1888), Baconia venusta (J. E. LeConte, 1845), Baconia riehli (Marseul, 1862), comb. n., Baconia scintillans sp. n., Baconia isthmia sp. n., Baconia rossi sp. n., Baconia navarretei sp. n., Baconia maculata sp. n., Baconia deliberata sp. n., Baconia excelsa sp. n., Baconia violacea (Marseul, 1853), Baconia varicolor (Marseul, 1887b), Baconia dives (Marseul, 1862), Baconia eximia (Lewis, 1888), Baconia splendida sp. n., Baconia jacinta sp. n., Baconia prasina sp. n., Baconia opulenta sp. n., Baconia illustris (Lewis, 1900), Baconia choaspites (Lewis, 1901), Baconia lewisi Mazur, 1984], Baconia salobrus group [Baconia salobrus (Marseul, 1887b), Baconia turgifrons sp. n., Baconia crassa sp. n., Baconia anthracina sp. n., Baconia emarginata sp. n., Baconia obsoleta sp. n.], Baconia ruficauda group [Baconia ruficauda sp. n., Baconia repens sp. n.], Baconia angusta group [Baconia angusta Schmidt, 1893a, Baconia incognita sp. n., Baconia guartela sp. n., Baconia bullifrons sp. n., Baconia cavei sp. n., Baconia subtilis sp. n., Baconia dentipes sp. n., Baconia rubripennis sp. n., Baconia lunatifrons sp. n.], Baconia aeneomicans group [Baconia aeneomicans (Horn, 1873), Baconia pulchella sp. n., Baconia quercea sp. n., Baconia stephani sp. n., Baconia irinae sp. n., Baconia fornix sp. n., Baconia slipinskii Mazur, 1981, Baconia submetallica sp. n., Baconia diminua sp. n., Baconia rufescens sp. n., Baconia punctiventer sp. n., Baconia aulaea sp. n., Baconia mustax sp. n., Baconia plebeia sp. n., Baconia castanea sp. n., Baconia lescheni sp. n., Baconia oblonga sp. n., Baconia animata sp. n., Baconia teredina sp. n., Baconia chujoi (Cooman, 1941), Baconia barbarus (Cooman, 1934), Baconia reposita sp. n., Baconia kubani sp. n., Baconia wallacea sp. n., Baconia bigemina sp. n., Baconia adebratti sp. n., Baconia silvestris sp. n.], Baconia cylindrica group [Baconia cylindrica sp. n., Baconia chatzimanolisi sp. n.], Baconia gibbifer group [Baconia gibbifer sp. n., B. piluliformis sp. n., Baconia maquipucunae sp. n., Baconia tenuipes sp. n., Baconia tuberculifer sp. n., Baconia globosa sp. n.], Baconia insolita group [Baconia insolita (Schmidt, 1893a), comb. n., Baconia burmeisteri (Marseul, 1870), Baconia tricolor sp. n., Baconia pilicauda sp. n.], Baconia riouka group [Baconia riouka (Marseul, 1861), Baconia azuripennis sp. n.], Baconia famelica group [Baconia famelica sp. n., Baconia grossii sp. n., Baconia redemptor sp. n., Baconia fortis sp. n., Baconia longipes sp. n., Baconia katieae sp. n., Baconia cavifrons (Lewis, 1893), comb. n., Baconia haeterioides sp. n.], Baconia micans group [Baconia micans (Schmidt, 1889a), Baconia carinifrons sp. n., Baconia fulgida (Schmidt, 1889c)], Baconia incertae sedis [Baconia chilense (Redtenbacher, 1867), Baconia glauca (Marseul, 1884), Baconia coerulea (Bickhardt, 1917), Baconia angulifrons sp. n., Baconia sanguinea sp. n., Baconia viridimicans (Schmidt, 1893b), Baconia nayarita sp. n., Baconia viridis sp. n., Baconia purpurata sp. n., Baconia aenea sp. n., Baconia clemens sp. n., Baconia leivasi sp. n., Baconia atricolor sp. n.]. We designate lectotypes for the following species: Baconia loricata Lewis, 1885,Phelister gounellei Marseul, 1887, Baconia jubaris Lewis, 1901, Baconia festiva Lewis, 1891, Platysoma venustum J.E. LeConte, 1845, Phelister riehli Marseul, 1862, Phelister violaceus Marseul, 1853, Phelister varicolor Marseul, 1887b, Phelister illustris Lewis, 1900, Baconia choaspites Lewis, 1901, Epierus festivus Lewis, 1898, Phelister salobrus Marseul, 1887, Baconia angusta Schmidt, 1893a, Phelister insolitus Schmidt, 1893a, Pachycraerus burmeisteri Marseul, 1870, Phelister riouka Marseul, 1861, Homalopygus cavifrons Lewis, 1893, Phelister micans Schmidt, 1889a, Phelister coeruleus Bickhardt, 1917, and Phelister viridimicans Schmidt, 1893b. We designate neotypes for Baconia patula Lewis, 1885 and Hister aeneomicans Horn, 1873, whose type specimens are lost. PMID:24194656
2011-03-04
Research, the Defense Threat Reduction Agency, and the Department of Energy. DAD is indebted to the Robert Ramsay Endowment of the University of Alabama...Schmidt, M. W., Baldridge, K. K., Boatz, J.A., Elbert, S.T., Gordon , M.S., Jensen, J.H., Koseki, S., Matsunaga, N., Nguyen, K.A., Su, S., Windus, T.L...Dupuis, M., Montgomery, J.A.; J. Comput. Chem., 1993, 14, 1347-1363.; Gordon , M. S., Schmidt, M. W., pp. 1167-1189, in "Theory and Applications of
Two new Auletta Schmidt, 1870 (Axinellidae; Demospongiae; Porifera) from Brazil.
Cavalcanti, Thaynã; Recinos, Radharanne; Pinheiro, Ulisses
2017-06-01
The genus Auletta Schmidt, 1970 comprises 14 valid species, with six known from the Atlantic Ocean. The genus was previously recorded for the Brazilian coast only in 1967 from surveys in Pernambuco State. The present paper describes two new Auletta from Northeastern Brazil. Auletta akaroa sp. nov. is from Alagoas State and it has a stalked tubular shape and small sinuous styles and strongyles. Auletta laboreli sp. nov. was found in Pernambuco State and it is a sponge with a cylindrical and cavernous body composed of styles with blunt and telescopic tips and sinuous strongyles. Both new species were compared with the other valid species of Auletta. The spicule complement and external morphology of the new species are discussed.
Hong Kong homeopathy: how it arrived and how it connected with Chinese medicine.
Fan, Ka-wai
2010-07-01
Translated as 'Shunshi Liaofa' in Mandarin, homeopathy received considerable attention from local physicians, thanks to Dr Heribert Schmidt who shared his views on the similarities between this western medical therapy and Chinese medicine during his visit to Hong Kong in 1954. Considered widely as non-scientific and superstitious, Chinese medicine was pushed to the periphery during the 1950s. On the contrary, adopted by western advanced countries, homeopathy was generally regarded as scientific and reliable. Schmidt's acknowledgement of the scientific roots of Chinese medicine excited many traditional therapists. The purpose of this paper is to trace the history of how homeopathy was introduced to Hong Kong and discuss its relationship with scientification of Chinese medicine. 2010 Elsevier Ltd. All rights reserved.
On the parameters influencing air-water gas exchange
NASA Astrophysics Data System (ADS)
JäHne, Bernd; Münnich, Karl Otto; BöSinger, Rainer; Dutzi, Alfred; Huber, Werner; Libner, Peter
1987-02-01
Detailed gas exchange measurements from two circular and one linear wind/wave tunnels are presented. Heat, He, CH4, CO2, Kr, and Xe have been used as tracers. The experiments show the central importance of waves for the water-side transfer process. With the onset of waves the Schmidt number dependence of the transfer velocity k changes from k ∝ Sc-⅔ to k ∝ Sc-½indicating a change in the boundary conditions at the surface. Moreover, energy put into the wave field by wind is transferred to near-surface turbulence enhancing gas transfer. The data show that the mean square slope of the waves is the best parameter to characterize the free wavy surface with respect to water-side transfer processes.
NASA Astrophysics Data System (ADS)
Desantes, J. M.; Salvador, F. J.; López, J. J.; de La Morena, J.
2011-02-01
In this paper, a research aimed at quantifying mass and momentum transfer in the near-nozzle field of diesel sprays injected into stagnant ambient air is reported. The study combines X-ray measurements for two different nozzles and axial positions, which provide mass distributions in the spray, with a theoretical model based on momentum flux conservation, which was previously validated. This investigation has allowed the validation of Gaussian profiles for local fuel concentration and velocity near the nozzle exit, as well as the determination of Schmidt number at realistic diesel spray conditions. This information could be very useful for those who are interested in spray modeling, especially at high-pressure injection conditions.
NASA Astrophysics Data System (ADS)
Watson, Linda C.; Martini, Paul; Lisenfeld, Ute; Böker, Torsten; Schinnerer, Eva
2016-01-01
Studying star formation beyond the optical radius of galaxies allows us to test empirical relations in extreme conditions with low average gas density and low molecular fraction. Previous studies discovered galaxies with extended ultraviolet (XUV) discs, which often contain star-forming regions with lower Hα-to-far-UV (FUV) flux ratios compared to inner disc star-forming regions. However, most previous studies lack measurements of molecular gas, which is presumably the component of the interstellar medium out of which stars form. We analysed published CO measurements and upper limits for 15 star-forming regions in the XUV or outer disc of three nearby spiral galaxies and a new CO upper limit from the IRAM (Institut de Radioastronomie Millimétrique) 30 m telescope in one star-forming region at r = 3.4r25 in the XUV disc of NGC 4625. We found that the star-forming regions are in general consistent with the same molecular-hydrogen Kennicutt-Schmidt law that applies within the optical radius, independent of whether we used Hα or FUV as the star formation rate (SFR) tracer. However, a number of the CO detections are significantly offset towards higher SFR surface density for their molecular-hydrogen surface density. Deeper CO data may enable us to use the presence or absence of molecular gas as an evolutionary probe to break the degeneracy between age and stochastic sampling of the initial mass function as the explanation for the low Hα-to-FUV flux ratios in XUV discs.
NASA Astrophysics Data System (ADS)
Park, J.; Hyun, C.; Cho, H.; Park, H.
2010-12-01
Physical weathering caused by freeze-thaw action in cold regions was simulated with artificial weathering simulator in laboratory. Physical weathering of rock in cold regions usually depends on the temperature, rock type and moisture content. Then these three variables were considered in this study. The laboratory freeze-thaw tests were conducted on the three types of rocks, e.g. diorite, basalt and tuff, which are the major rock types around Sejong Station, King George Island, Antarctica. Nine core samples composed of three samples from each rock type were prepared in NX core, and 50 cycles of freeze-thaw test was carried out under dried and saturated water conditions. In this study, the physical weathering of rocks was investigated after each 10 cycles by measuring P-wave velocity, bulk density, effective porosity, Schmidt hardness and uniaxial compression strength(UCS). The experimental result of the diorite and the tuff specimens showed that P-wave velocity, bulk density, effective porosity, Schmidt hardness and UCS were gradually decreased as weathering progresses, but the result of the basalt specimens did not show typical trends due to the characteristics of irregular pore distribution and various pore sizes. Scanning electron microscopy(SEM) photographs of diorite, basalt and tuff specimens weathered in dried and saturated conditions were also acquired to investigate the role of water during physical weathering processes. The number and size of microcracks were increased as weathering progresses. This work was supported by the National Research Foundation of Korea(NRF) Grant(NRF-2010-0027753).
Kennicutt-Schmidt Relation Variety and Star-forming Cloud Fraction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morokuma-Matsui, Kana; Muraoka, Kazuyuki, E-mail: kana.matsui@nao.ac.jp
2017-03-10
The observationally derived Kennicutt-Schmidt (KS) relation slopes differ from study to study, ranging from sublinear to superlinear. We investigate the KS-relation variety (slope and normalization) as a function of integrated intensity ratio, R {sub 31} = CO( J = 3–2)/CO( J = 1–0) using spatially resolved CO( J = 1–0), CO( J = 3–2), H i, H α, and 24 μ m data of three nearby spiral galaxies (NGC 3627, NGC 5055, and M83). We find that (1) the slopes for each subsample with a fixed R {sub 31} are shallower, but the slope for all data sets combined becomesmore » steeper, (2) normalizations for high R {sub 31} subsamples tend to be high, (3) R {sub 31} correlates with star formation efficiency, therefore the KS relation depends on the distribution in R {sub 31}–Σ{sub gas} space of the samples: no Σ{sub gas} dependence of R {sub 31} results in a linear slope of the KS relation, whereas a positive correlation between Σ{sub gas} and R {sub 31} results in a superlinear slope of the KS relation, and (4) R {sub 31}–Σ{sub gas} distributions are different from galaxy to galaxy and within a galaxy: galaxies with prominent galactic structure tend to have large R {sub 31} and Σ{sub gas}. Our results suggest that the formation efficiency of a star-forming cloud from molecular gas is different among galaxies as well as within a galaxy, and it is one of the key factors inducing the variety in galactic KS relation.« less
Grams, Paul E.; Buscombe, Daniel D.; Topping, David J.; Hazel, Joseph E.; Kaplinski, Matt
2015-01-01
The magnitude and pfattern of streamflow and sediment supply of the Colorado River in Grand Canyon (Figure 1) has been affected by the existence and operations of Glen Canyon Dam since filling of Lake Powell Reservoir began in March 1963. In the subsequent 30 years, fine sediment was scoured from the downstream channel (Topping et al., 2000; Grams et al., 2007), resulting in a decline in the number and size of sandbars in the eastern half of Grand Canyon National Park (Wright et al., 2005; Schmidt et al., 2004). The Glen Canyon Dam Adaptive Management Program (GCDAMP) administered by the U.S. Department of Interior oversees efforts to manage the Colorado River ecosystem downstream from Glen Canyon Dam. One of the goals of the GCDAMP is to maintain and increase the number and size of sandbars in this context of a limited sand supply. Management actions to benefit sandbars have included curtailment of daily streamflow fluctuations, which occur for hydropower generation, and implementation of controlled floods, also called high-flow experiments.Studies of controlled floods, defined as intentional releases that exceed the maximum discharge capacity of the Glen Canyon Dam powerplant, implemented between 1996 and 2008, have demonstrated that these events cause increases in sandbar size throughout Marble and Grand Canyons (Hazel et al., 2010; Schmidt and Grams, 2011; Mueller et al., 2014), although the magnitude of response is spatially variable (Hazel et al., 1999; 2010). Controlled floods may build some sandbars at the expense of erosion of sand from other, upstream, sandbars (Schmidt, 1999). To increase the frequency and effectiveness of sandbar building, the U.S. Department of Interior adopted a “high-flow experimental protocol” to implement controlled floods regularly under conditions of enriched sand supply (U.S. Department of Interior, 2012). Because the supply of sand available to build sandbars has been substantially reduced by Glen Canyon Dam (Topping et al., 2000) and depends entirely on infrequent tributary floods, monitoring of both sandbars and gross sand storage (the sand budget) is required to evaluate whether the high-flow protocol is having the intended effect of increasing sandbar size without progressively depleting sand from the system.There are many challenges associated with monitoring sand storage and active sand deposits in a river system as large and complex as the 450-km segment of the Colorado River between Glen Canyon Dam and Lake Mead. Previous studies have demonstrated the temporal variation in sand storage associated with sand-supply limitation (Topping et al., 2000) and the spatial variability in the amount of sand stored in eddies and the channel associated with channel hydraulics (Grams et al., 2013). In this study, we report on companion measurements of sand flux and morphologic change to quantify, for the first time, the relation between changes in sand mass balance, changes in within-channel sand storage, and changes in sandbars comprehensively for a 50-km river segment of the Colorado River in lower Marble Canyon within Grand Canyon National Park.We show that, when measured over the scale of a 50-km river segment, these complementary measurements of the sand budget agree within measurement uncertainty and provide a rare opportunity to integrate the temporally rich sand-flux record with the spatially rich morphologic measurements. Both methods show that sediment was evacuated from lower Marble Canyon over the 3-year study period. The flux-based budget shows the timing of changes in storage relative to dam-release patterns, while the morphologic measurements depict the spatial distribution of erosion and deposition among different depositional settings.
The number comb for a soil physical properties dynamic measurement
NASA Astrophysics Data System (ADS)
Olechko, K.; Patiño, P.; Tarquis, A. M.
2012-04-01
We propose the prime numbers distribution extracted from the soil digital multiscale images and some physical properties time series as the precise indicator of the spatial and temporal dynamics under soil management changes. With this new indicator the soil dynamics can be studied as a critical phenomenon where each phase transition is estimated and modeled by the graph partitioning induced phase transition. The critical point of prime numbers distribution was correlated with the beginning of Andosols, Vertisols and saline soils physical degradation under the unsustainable soil management in Michoacan, Guanajuato and Veracruz States of Mexico. The data banks corresponding to the long time periods (between 10 and 28 years) were statistically compared by RISK 5.0 software and our own algorithms. Our approach makes us able to distill free-form natural laws of soils physical properties dynamics directly from the experimental data. The Richter (1987) and Schmidt and Lipson (2009) original approaches were very useful to design the algorithms to identify Hamiltonians, Lagrangians and other laws of geometric and momentum conservation especially for erosion case.
NASA Astrophysics Data System (ADS)
Zeeshan, A.; Shehzad, N.; Ellahi, R.
2018-03-01
The motivation of the current article is to explore the energy activation in MHD radiative Couette-Poiseuille flow nanofluid in horizontal channel with convective boundary conditions. The mathematical model of Buongiorno [1] effectively describes the current flow analysis. Additionally, the impact of chemical reaction is also taken in account. The governing flow equations are simplified with the help of boundary layer approximations. Non-linear coupled equations for momentum, energy and mass transfer are tackled with analytical (HAM) technique. The influence of dimensionless convergence parameter like Brownian motion parameter, radiation parameter, buoyancy ratio parameter, dimensionless activation energy, thermophoresis parameter, temperature difference parameter, dimensionless reaction rate, Schmidt number, Brinkman number, Biot number and convection diffusion parameter on velocity, temperature and concentration profiles are discussed graphically and in tabular form. From the results, it is elaborate that the nanoparticle concentration is directly proportional to the chemical reaction with activation energy and the performance of Brownian motion on nanoparticle concentration gives reverse pattern to that of thermophoresis parameter.
NASA Astrophysics Data System (ADS)
Lemaitre, Gerard R.; Montiel, Pierre; Joulie, Patrice; Dohlen, Kjetil; Lanzoni, Patrick
2004-09-01
Wide-field astronomy requires larger size telescopes. Compared to the catadioptric Schmidt, the optical properties of a three mirror telescope provides significant advantages. (1) The flat field design is anastigmatic at any wavelength, (2) the system is extremely compact -- four times shorter than a Schmidt -- and, (3) compared to a Schmidt with refractive corrector -- requiring the polishing of three optical surfaces --, the presently proposed Modified-Rumsey design uses all of eight available free parameters of a flat fielded anastigmatic three mirror telescope for mirrors generated by active optics methods. Compared to a Rumsey design, these parameters include the additional slope continuity condition at the primary-tertiary link for in-situ stressing and aspherization from a common sphere. Then, active optics allows the polishing of only two spherical surfaces: the combined primary-tertiary mirror and the secondary mirror. All mirrors are spheroids of the hyperboloid type. This compact system is of interest for space and ground-based astronomy and allows to built larger wide-field telescopes such as demonstrated by the design and construction of identical telescopes MINITRUST-1 and -2, f/5 - 2° FOV, consisting of an in-situ stressed double vase form primary-tertiary and of a stress polished tulip form secondary. Optical tests of these telescopes, showing diffraction limited images, are presented.
Modeling of Micro Deval abrasion loss based on some rock properties
NASA Astrophysics Data System (ADS)
Capik, Mehmet; Yilmaz, Ali Osman
2017-10-01
Aggregate is one of the most widely used construction material. The quality of the aggregate is determined using some testing methods. Among these methods, the Micro Deval Abrasion Loss (MDAL) test is commonly used for the determination of the quality and the abrasion resistance of aggregate. The main objective of this study is to develop models for the prediction of MDAL from rock properties, including uniaxial compressive strength, Brazilian tensile strength, point load index, Schmidt rebound hardness, apparent porosity, void ratio Cerchar abrasivity index and Bohme abrasion test are examined. Additionally, the MDAL is modeled using simple regression analysis and multiple linear regression analysis based on the rock properties. The study shows that the MDAL decreases with the increase of uniaxial compressive strength, Brazilian tensile strength, point load index, Schmidt rebound hardness and Cerchar abrasivity index. It is also concluded that the MDAL increases with the increase of apparent porosity, void ratio and Bohme abrasion test. The modeling results show that the models based on Bohme abrasion test and L type Schmidt rebound hardness give the better forecasting performances for the MDAL. More models, including the uniaxial compressive strength, the apparent porosity and Cerchar abrasivity index, are developed for the rapid estimation of the MDAL of the rocks. The developed models were verified by statistical tests. Additionally, it can be stated that the proposed models can be used as a forecasting for aggregate quality.
Mohamed, A M I; El-menshawy, Nabil; Saif, Amany M
2007-05-01
Pollutants in the form of non-aqueous phase liquids (NAPLs), such as petroleum products, pose a serious threat to the soil and groundwater. A mathematical model was derived to study the unsteady pollutant concentrations through water saturated contaminated soil under air sparging conditions for different NAPLs and soil properties. The comparison between the numerical model results and the published experimental results showed acceptable agreement. Furthermore, an experimental study was conducted to remove NAPLs from the contaminated soil using the sparging air technique, considering the sparging air velocity, air temperature, soil grain size and different contaminant properties. This study showed that sparging air at ambient temperature through the contaminated soil can remove NAPLs, however, employing hot air sparging can provide higher contaminant removal efficiency, by about 9%. An empirical correlation for the volatilization mass transfer coefficient was developed from the experimental results. The dimensionless numbers used were Sherwood number (Sh), Peclet number (Pe), Schmidt number (Sc) and several physical-chemical properties of VOCs and porous media. Finally, the estimated volatilization mass transfer coefficient was used for calculation of the influence of heated sparging air on the spreading of the NAPL plume through the contaminated soil.
NASA Astrophysics Data System (ADS)
Shah, Zahir; Islam, Saeed; Gul, Taza; Bonyah, Ebenezer; Altaf Khan, Muhammad
2018-06-01
The current research aims to examine the combined effect of magnetic and electric field on micropolar nanofluid between two parallel plates in a rotating system. The nanofluid flow between two parallel plates is taken under the influence of Hall current. The flow of micropolar nanofluid has been assumed in steady state. The rudimentary governing equations have been changed to a set of differential nonlinear and coupled equations using suitable similarity variables. An optimal approach has been used to acquire the solution of the modelled problems. The convergence of the method has been shown numerically. The impact of the Skin friction on velocity profile, Nusslet number on temperature profile and Sherwood number on concentration profile have been studied. The influences of the Hall currents, rotation, Brownian motion and thermophoresis analysis of micropolar nanofluid have been mainly focused in this work. Moreover, for comprehension the physical presentation of the embedded parameters that is, coupling parameter N1 , viscosity parameter Re , spin gradient viscosity parameter N2 , rotating parameter Kr , Micropolar fluid constant N3 , magnetic parameter M , Prandtl number Pr , Thermophoretic parameter Nt , Brownian motion parameter Nb , and Schmidt number Sc have been plotted and deliberated graphically.
Determination of proper motions in the Pleiades cluster
NASA Astrophysics Data System (ADS)
Schilbach, E.
1991-04-01
For 458 stars in the Pleiades field from the catalog of Eichhorn et al. (1970) proper motions were derived on Tautenburg and CERGA Schmidt telescope plates measured with the automated measuring machine MAMA in Paris. The catalog positions were considered as first epoch coordinates with an epoch difference of ca. 33 years to the observations. The results show good coincidence of proper motions derived with both Schmidt telescopes within the error bars. Comparison with proper motions determined by Vasilevskis et al. (1979) displays some significant differences but no systematic effects depending on plate coordinates or magnitudes could be found. An accuracy of 0.3 arcsec/100a for one proper motion component was estimated. According to the criterion of common proper motion 34 new cluster members were identified.
NASA Technical Reports Server (NTRS)
Wegner, Gary A.
1988-01-01
Recent research under NASA grant NAG5-971 consisted of the performance of two projects in conjunction with the International Ultraviolet Explorer (IUE) satellites. These are: (1) to look at the ultraviolet spectra of subluminous stars identified from visual wavelength spectroscopy that had been originally discovered from the Kiso Schmidt survey for ultraviolet excess stars and (2) to carry out a systematic reanalysis of the archived IUE spectra of white dwarfs. This report presents information on the progress of the re-reduction of over 600 IUE white dwarf spectra and their subsequent analysis employing model atmospheres and the observation of the Kiso ultraviolet excess stars.
Shi, Hongliang; Liang, Hongbin
2018-01-01
Nine taxa of the genus Pericalus Macleay from China are revised, with four new species described: Pericalus gibbosus sp. n. (type locality: Putao, Myanmar; one paratype from Mêdog, Xizang), Pericalus elegans sp. n. (type locality: Mêdog, Xizang), Pericalus acutidens sp. n. (type locality: Longchuan, Yunnan), and Pericalus obscuratus sp. n. (type locality: Fanjingshan, Guizhou). Four taxa are newly recorded from China: Pericalus ornatus ornatus Schmidt-Göbel (Yunnan, Hainan), P. obtusipennis Fedorenko (Yunnan), P. amplus Andrewes (Yunnan), and P. dux Andrewes (Yunnan). Pericalus formosanus Dupuis is newly ranked as a subspecies of P. ornatus Schmidt-Göbel. An improved key to world species of the subgenus Pericalus is provided, along with distribution maps and images of habitus and male and female genitalia for all Chinese species.
Physical characterization of a watershed through GIS: a study in the Schmidt stream, Brazil.
Reis, D R; Plangg, R; Tundisi, J G; Quevedo, D M
2015-12-01
Remote sensing and geoprocessing are essential tools for obtaining and maintaining records of human actions on space over the course of time; these tools offer the basis for diagnoses of land use, environmental interference and local development. The Schmidt stream watershed, located in the Sinos River basin, in southern Brazil, has an environmental situation similar to that of the majority of small streams draining rural and urban areas in southern Brazil: agricultural and urbanization practices do not recognize the riparian area and there is removal of original vegetation, disregarding the suitability of land use; removal of wetlands; intensive water use for various activities; and lack of control and monitoring in the discharge of wastewater, among other factors, deteriorate the quality of this important environment.This article aims to achieve a physical characterization of the Schmidt stream watershed (Sinos river basin) identifying elements such as land use and occupation, soil science, geology, climatology, extent and location of watershed, among others, so as to serve as the basis for a tool that helps in the integrated environmental management of watersheds. By applying geographic information system - GIS to the process of obtaining maps of land use and occupation, pedologicaland geological, and using climatological data from the Campo Bom meteorological station, field visit, review of literature and journals, and publicly available data, the physical characterization of the Schmidt stream watershed was performed, with a view to the integrated environmental management of this watershed. Out of the total area of the Schmidt stream watershed (23.92 km(2)), in terms of geology, it was observed that 23.7% consist of colluvial deposits, 22.6% consist of grass facies, and 53.7% consist of Botucatu formation. Major soil types of the watershed: 97.4% Argisols and only 2.6% Planosols. Land use and occupation is characterized by wetland (0.5%), Native Forest (12.83%), Native Forest + Rural Anthropic + Secondary Vegetation + Forestry (43.81%), Urban Anthropic/Urban Area (39.85%), and also Urban Anthropic/Expansion areas (3.01%). Mean annual rainfall is 1337 mm, maximum temperatures range from 10.5°C to 41.6°C and minimum temperatures range from -1.80°C and 26°C, weak winds, occasionally over 5 m/s. Conducting an environmental assessment in this watershed is essential for environmental and land management. However, these assessments are not conducted in all watersheds and, when they are, their frequency is not sufficiency to allow for continuous monitoring, in order to model and predict scenarios, with a view to adopt medium and long-term measures for environmental protection.
Particle dynamics in a viscously decaying cat's eye: The effect of finite Schmidt numbers
NASA Astrophysics Data System (ADS)
Newton, P. K.; Meiburg, Eckart
1991-05-01
The dynamics and mixing of passive marker particles for the model problem of a decaying cat's eye flow is studied. The flow field corresponds to Stuart's one-parameter family of solutions [J. Fluid Mech. 29, 417 (1967)]. It is time dependent as a result of viscosity, which is modeled by allowing the free parameter to depend on time according to the self-similar solution of the Navier-Stokes equations for an isolated point vortex. Particle diffusion is numerically simulated by a random walk model. While earlier work had shown that, for small values of time over Reynolds number t/Re≪1, the interval length characterizing the formation of lobes of fluid escaping from the cat's eye scales as Re-1/2, the present study shows that, for the case of diffusive effects and t/Pe≪1, the scaling follows Pe-1/4. A simple argument, taking into account streamline convergence and divergence in different parts of the flow field, explains the Pe-1/4 scaling.
Sensitivity to. gamma. rays of avian sarcoma and murine leukemia viruses. [/sup 60/Co, uv
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toyoshima, K.; Niwa, O.; Yutsudo, M.
1980-09-01
The direct inactivation of avian and murine oncoviruses by ..gamma.. rays was examined using /sup 60/Co as a ..gamma..-ray source. The inactivation of murine leukemia virus (M-MuLV) followed single-hit kinetics while the subgroup D Schmidt-Ruppin strain of avian sarcoma virus (SR-RSV D) showed multihit inactivation kinetics with an extrapolation number of 5. The two viruses showed similar uv-inactivation kinetics. The genomic RNA of the SR-RSV D strain was degraded by ..gamma.. irradiation faster than its infectivity, but viral clones isolated from the foci formed after ..gamma.. irradiation had a complete genome. These results suggest that SR-RSV D has a strongmore » repair function, possibly connected with reverse transcriptase activity.« less
NASA Astrophysics Data System (ADS)
Shamsoddini, Rahim
2018-04-01
An incompressible smoothed particle hydrodynamics algorithm is proposed to model and investigate the thermal effect on the mixing rate of an active micromixer in which the rotating stirrers enhance the mixing rate. In liquids, mass diffusion increases with increasing temperature, while viscosity decreases; so, the local Schmidt number decreases considerably with increasing temperature. The present study investigates the effect of wall temperature on mixing rate with an improved SPH method. The robust SPH method used in the present work is equipped with a shifting algorithm and renormalization tensors. By introducing this new algorithm, the several mass, momentum, energy, and concentration equations are solved. The results, discussed for different temperature ratios, show that mixing rate increases significantly with increased temperature ratio.
Resolving the Mass Production and Surface Structure of the Enceladus Dust Plume
NASA Astrophysics Data System (ADS)
Kempf, Sascha; Southworth, Benjamin; Spitale, Joseph; Srama, Ralf; Schmidt, Jürgen; Postberg, Frank
2017-04-01
There are ongoing arguments with regards to the Enceldaus plume, both on the total mass of ice particles produced by the plume in kg/s, as well as the structure of plume ejection along the tiger stripes. Herein, results from Cassini's Cosmic Dust Analyzer (CDA) and Imaging Science Subsystem (ISS) are used in conjunction with large-scale plume simulations to resolve each of these issues. Additional results are provided on the short-term variability of the plume, and the relation of specifc surface deposition features to emissions along given areas of the tiger stripes. By adjusting their plume model to the dust flux measured by the Cassini dust detector during the close Enceladus flyby in 2005, Schmidt et al. (2008) obtained a total dust production rate in the plumes of about
76 FR 18938 - Changes in Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-06
... Isles Beach, 18070 Review. Collins Avenue, Sunny Isles Beach, FL 33160. Monroe (FEMA Docket No.: B.... Jim Schmidt, December 24, 2010 460277 No.: B-1156) of Lincoln County August 26, 2010; Chairman...
Small Astronomy Payloads for Spacelab. [conferences
NASA Technical Reports Server (NTRS)
Bohlin, R. C. (Editor)
1975-01-01
The workshop to define feasible concepts in the UV-optical 1R area for Astronomy Spacelab Payloads is reported. Payloads proposed include: high resolution spectrograph, Schmidt camera spectrograph, UV telescope, and small infrared cryogenic telescope.
Genetics Home Reference: Sézary syndrome
... Bastidas Torres AN, Vermeer MH, Zoutman WH, Tensen CP, Schmidt CA. Genetic rearrangements result in altered gene ... K, Knijnenburg J, Boer JM, Willemze R, Tensen CP. Oncogenomic analysis of mycosis fungoides reveals major differences ...
Connes distance function on fuzzy sphere and the connection between geometry and statistics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Devi, Yendrembam Chaoba, E-mail: chaoba@bose.res.in; Chakraborty, Biswajit, E-mail: biswajit@bose.res.in; Prajapat, Shivraj, E-mail: shraprajapat@gmail.com
An algorithm to compute Connes spectral distance, adaptable to the Hilbert-Schmidt operatorial formulation of non-commutative quantum mechanics, was developed earlier by introducing the appropriate spectral triple and used to compute infinitesimal distances in the Moyal plane, revealing a deep connection between geometry and statistics. In this paper, using the same algorithm, the Connes spectral distance has been calculated in the Hilbert-Schmidt operatorial formulation for the fuzzy sphere whose spatial coordinates satisfy the su(2) algebra. This has been computed for both the discrete and the Perelemov’s SU(2) coherent state. Here also, we get a connection between geometry and statistics which ismore » shown by computing the infinitesimal distance between mixed states on the quantum Hilbert space of a particular fuzzy sphere, indexed by n ∈ ℤ/2.« less
IAU Working Group on Wide-Field Imaging.
NASA Astrophysics Data System (ADS)
MacGillivray, H. T.
1991-01-01
Contents: 1. Introduction - The IAU Working Group on Wide-Field Imaging (R. M. West). 2. Reports from the Sub-Sections of the Working Group - a. Sky surveys and patrols (R. M. West). b. Photographic techniques (D. F. Malin). c. Digitization techniques (H. T. MacGillivray). d. Archival and retrieval of wide-field data (B. Lasker). 3. Meeting of the Organising Committee (R. M. West). 4. Wide-field plate archives (M. Tsvetkov). 5. Reproduction of the Palomar Observatory Sky Surveys (R. J. Brucato). 6. Status of the St ScI scan-distribution program (B. Lasker). 7. Pixel addition - pushing Schmidt plates to B = 25 (M. R. S. Hawkins). 8. Photometry from Estar film (S. Phillipps, Q. Parker). 9. ASCHOT - Astrophysical Schmidt Orbital Telescope (H. Lorenz). 10. The Hitchhiker parallel CCD camera (J. Davies, M. Disney, S. Driver, I. Morgan, S. Phillipps).
March of the Starbugs: Configuring Fiber-bearing Robots on the UK-Schmidt Optical Plane
NASA Astrophysics Data System (ADS)
Lorente, N. P. F.; Vuong, M.; Satorre, C.; Hong, S. E.; Shortridge, K.; Goodwin, M.; Kuehn, K.
2015-09-01
The TAIPAN instrument, currently being developed for the Australian Astronomical Observatory's UK Schmidt telescope at Siding Spring Observatory, makes use of the AAO's Starbug technology to deploy 150 science fibers to target positions on the optical plane. This paper describes the software system for controlling and deploying the fiber-bearing Starbug robots. The TAIPAN software is responsible for allocating each Starbug to its next target position based on its current position and the distribution of targets, finding a collision-free path for each Starbug, and then simultaneously controlling the Starbug hardware in a closed loop, with a metrology camera used to determine the position of each Starbug in the field during reconfiguration. The software is written in C++ and Java and employs a DRAMA middleware layer (Farrell et al. 1995).
Shi, Hongliang; Liang, Hongbin
2018-01-01
Abstract Nine taxa of the genus Pericalus Macleay from China are revised, with four new species described: Pericalus gibbosus sp. n. (type locality: Putao, Myanmar; one paratype from Mêdog, Xizang), Pericalus elegans sp. n. (type locality: Mêdog, Xizang), Pericalus acutidens sp. n. (type locality: Longchuan, Yunnan), and Pericalus obscuratus sp. n. (type locality: Fanjingshan, Guizhou). Four taxa are newly recorded from China: Pericalus ornatus ornatus Schmidt-Göbel (Yunnan, Hainan), P. obtusipennis Fedorenko (Yunnan), P. amplus Andrewes (Yunnan), and P. dux Andrewes (Yunnan). Pericalus formosanus Dupuis is newly ranked as a subspecies of P. ornatus Schmidt-Göbel. An improved key to world species of the subgenus Pericalus is provided, along with distribution maps and images of habitus and male and female genitalia for all Chinese species. PMID:29844711
Comparison and evaluation on image fusion methods for GaoFen-1 imagery
NASA Astrophysics Data System (ADS)
Zhang, Ningyu; Zhao, Junqing; Zhang, Ling
2016-10-01
Currently, there are many research works focusing on the best fusion method suitable for satellite images of SPOT, QuickBird, Landsat and so on, but only a few of them discuss the application of GaoFen-1 satellite images. This paper proposes a novel idea by using four fusion methods, such as principal component analysis transform, Brovey transform, hue-saturation-value transform, and Gram-Schmidt transform, from the perspective of keeping the original image spectral information. The experimental results showed that the transformed images by the four fusion methods not only retain high spatial resolution on panchromatic band but also have the abundant spectral information. Through comparison and evaluation, the integration of Brovey transform is better, but the color fidelity is not the premium. The brightness and color distortion in hue saturation-value transformed image is the largest. Principal component analysis transform did a good job in color fidelity, but its clarity still need improvement. Gram-Schmidt transform works best in color fidelity, and the edge of the vegetation is the most obvious, the fused image sharpness is higher than that of principal component analysis. Brovey transform, is suitable for distinguishing the Gram-Schmidt transform, and the most appropriate for GaoFen-1 satellite image in vegetation and non-vegetation area. In brief, different fusion methods have different advantages in image quality and class extraction, and should be used according to the actual application information and image fusion algorithm.
Weathering Grade Classification of Granite Stone Monument Using Reflectance Spectroscopy
NASA Astrophysics Data System (ADS)
Hyun, C.; Roh, T.; Choi, M.; Park, H.
2009-05-01
Stone monument has been placed in field and exposed to rain and wind. This outdoor environment and air pollution induced weathering of stone monument. Weathering grade classification is necessary to manage and conserve stone monuments. Visual interpretation by geologist and laboratory experiments using specimens fallen off from the monument to avoid damage on the monument have been applied to classify weathering grade conventionally. Rocks and minerals absorb some particular wavelength ranges of electromagnetic energy by electronic process and vibrational process of composing elements and these phenomena produce intrinsic diagnostic spectral reflectance curve. Non-destructive technique for weathering degree assessment measures those diagnostic absorption features of weathering products and converts the depths of features related to abundance of the materials to relative weathering degree. We selected granite outcrop to apply conventional six folded weathering grade classification method using Schmidt hammer rebound teste. The correlations between Schmidt hammer rebound values and absorption depths of iron oxides such as ferric oxide in the vicinity of 0.9 micrometer wavelength and clay minerals such as illite and kaolinite in the vicinity of 2.2 micrometer wavelength, representative weathering products of granite, were analyzed. The Schmidt hammer rebound value decreased according to increase of absorption depths induced from those weathering products. Weathering grade classification on the granite stone monument was conducted by using absorption depths of weathering products This research is supported from National Research Institute of Cultural Heritage and we appreciate for this.
The SuperCOSMOS all-sky galaxy catalogue
NASA Astrophysics Data System (ADS)
Peacock, J. A.; Hambly, N. C.; Bilicki, M.; MacGillivray, H. T.; Miller, L.; Read, M. A.; Tritton, S. B.
2016-10-01
We describe the construction of an all-sky galaxy catalogue, using SuperCOSMOS scans of Schmidt photographic plates from the UK Schmidt Telescope and Second Palomar Observatory Sky Survey. The photographic photometry is calibrated using Sloan Digital Sky Survey data, with results that are linear to 2 per cent or better. All-sky photometric uniformity is achieved by matching plate overlaps and also by requiring homogeneity in optical-to-2MASS colours, yielding zero-points that are uniform to 0.03 mag or better. The typical AB depths achieved are BJ < 21, RF < 19.5 and IN < 18.5, with little difference between hemispheres. In practice, the IN plates are shallower than the BJ and RF plates, so for most purposes we advocate the use of a catalogue selected in these two latter bands. At high Galactic latitudes, this catalogue is approximately 90 per cent complete with 5 per cent stellar contamination; we quantify how the quality degrades towards the Galactic plane. At low latitudes, there are many spurious galaxy candidates resulting from stellar blends: these approximately match the surface density of true galaxies at |b| = 30°. Above this latitude, the catalogue limited in BJ and RF contains in total about 20 million galaxy candidates, of which 75 per cent are real. This contamination can be removed, and the sky coverage extended, by matching with additional data sets. This SuperCOSMOS catalogue has been matched with 2MASS and with WISE, yielding quasi-all-sky samples of respectively 1.5 million and 18.5 million galaxies, to median redshifts of 0.08 and 0.20. This legacy data set thus continues to offer a valuable resource for large-angle cosmological investigations.
NASA Astrophysics Data System (ADS)
Magee, Madeline R.; Wu, Chin H.
2017-12-01
Water temperatures and stratification are important drivers for ecological and water quality processes within lake systems, and changes in these with increases in air temperature and changes to wind speeds may have significant ecological consequences. To properly manage these systems under changing climate, it is important to understand the effects of increasing air temperatures and wind speed changes in lakes of different depths and surface areas. In this study, we simulate three lakes that vary in depth and surface area to elucidate the effects of the observed increasing air temperatures and decreasing wind speeds on lake thermal variables (water temperature, stratification dates, strength of stratification, and surface heat fluxes) over a century (1911-2014). For all three lakes, simulations showed that epilimnetic temperatures increased, hypolimnetic temperatures decreased, the length of the stratified season increased due to earlier stratification onset and later fall overturn, stability increased, and longwave and sensible heat fluxes at the surface increased. Overall, lake depth influences the presence of stratification, Schmidt stability, and differences in surface heat flux, while lake surface area influences differences in hypolimnion temperature, hypolimnetic heating, variability of Schmidt stability, and stratification onset and fall overturn dates. Larger surface area lakes have greater wind mixing due to increased surface momentum. Climate perturbations indicate that our larger study lakes have more variability in temperature and stratification variables than the smaller lakes, and this variability increases with larger wind speeds. For all study lakes, Pearson correlations and climate perturbation scenarios indicate that wind speed has a large effect on temperature and stratification variables, sometimes greater than changes in air temperature, and wind can act to either amplify or mitigate the effect of warmer air temperatures on lake thermal structure depending on the direction of local wind speed changes.
Multiple Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California
Pike, Richard J.; Graymer, Russell W.
2008-01-01
With the exception of Los Angeles, perhaps no urban area in the United States is more at risk from landsliding, triggered by either precipitation or earthquake, than the San Francisco Bay region of northern California. By January each year, seasonal winter storms usually bring moisture levels of San Francisco Bay region hillsides to the point of saturation, after which additional heavy rainfall may induce landslides of various types and levels of severity. In addition, movement at any time along one of several active faults in the area may generate an earthquake large enough to trigger landslides. The danger to life and property rises each year as local populations continue to expand and more hillsides are graded for development of residential housing and its supporting infrastructure. The chapters in the text consist of: *Introduction by Russell W. Graymer *Chapter 1 Rainfall Thresholds for Landslide Activity, San Francisco Bay Region, Northern California by Raymond C. Wilson *Chapter 2 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike and Steven Sobieszczyk *Chapter 3 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven Sobieszczyk *Chapter 4 Landslide Hazard Modeled for the Cities of Oakland, Piedmont, and Berkeley, Northern California, from a M=7.1 Scenario Earthquake on the Hayward Fault Zone by Scott B. Miles and David K. Keefer *Chapter 5 Synthesis of Landslide-Hazard Scenarios Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike The plates consist of: *Plate 1 Susceptibility to Deep-Seated Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Richard J. Pike, Russell W. Graymer, Sebastian Roberts, Naomi B. Kalman, and Steven Sobieszczyk *Plate 2 Susceptibility to Shallow Landsliding Modeled for the Oakland-Berkeley Area, Northern California by Kevin M. Schmidt and Steven Sobieszczyk *Plate 3 Susceptibility to Shallow Landsliding Modeled for the Cities of Oakland and Piedmont Northern California by Kevin M. Schmidt and Steven Sobieszczyk *Plate 4 Seismic Landslide Hazard Modeled for the Cities of Oakland, Piedmont, and Berkeley, Northern California by Scott B. Miles and David K. Keefer III The relative hazard for each of several landslide scenarios is presented as a geospatial database. This publication includes ARC/INFO (Environmental Systems Research Institute, http://www.esri.com) version 8.1.2 grids and associated tables and four text files of FGDC-compliant metadata for each grid.
Constraining the Galactic structure parameters with the XSTPS-GAC and SDSS photometric surveys
NASA Astrophysics Data System (ADS)
Chen, B.-Q.; Liu, X.-W.; Yuan, H.-B.; Robin, A. C.; Huang, Y.; Xiang, M.-S.; Wang, C.; Ren, J.-J.; Tian, Z.-J.; Zhang, H.-W.
2017-01-01
Photometric data from the Xuyi Schmidt Telescope Photometric Survey of the Galactic Anticentre (XSTPS-GAC) and the Sloan Digital Sky Survey (SDSS) are used to derive the global structure parameters of the smooth components of the Milky Way. The data, which cover nearly 11 000 deg2 sky area and the full range of Galactic latitude, allow us to construct a globally representative Galactic model. The number density distribution of Galactic halo stars is fitted with an oblate spheroid that decays by power law. The best fitting yields an axis ratio and a power-law index κ = 0.65 and p = 2.79, respectively. The r-band differential star counts of three dwarf samples are then fitted with a Galactic model. The best-fitting model yielded by a Markov Chain Monte Carlo analysis has thin and thick disc scale heights and lengths of H1 = 322 pc and L1 = 2343 pc, H2 = 794 pc and L2 = 3638 pc, a local thick-to-thin disc density ratio of f2 = 11 per cent, and a local density ratio of the oblate halo to the thin disc of fh = 0.16 per cent. The measured star count distribution, which is in good agreement with the above model for most of the sky area, shows a number of statistically significant large-scale overdensities, including some of the previously known substructures, such as the Virgo overdensity and the so-called `north near structure', and a new feature between 150° < l < 240° and -1° < b < -5°, at an estimated distance between 1.0 and 1.5 kpc. The Galactic North-South asymmetry in the anticentre is even stronger than previously thought.
NASA Astrophysics Data System (ADS)
Xu, Jie; Wang, Xin; Mu, Baozhong; Zhan, Qi; Xie, Qing; Li, Yaran; Chen, Yifan; He, Yanan
2016-10-01
In order to counter drug-related crimes effectively, and to safeguard homeland security as well as public safety, it is important to inspect drugs, explosives and other contraband quickly and accurately from the express mail system, luggage, vehicles and other objects. In this paper, we discuss X-ray backscatter inspection system based on a novel lobster-eye X-ray objective, which is an effective inspection technology for drugs, explosives and other contraband inspection. Low atomic number materials, such as drugs and explosives, leads to strong Compton scattering after irradiated by X-ray, which is much stronger than high atomic number material, such as common metals, etc. By detecting the intensity of scattering signals, it is possible to distinguish between organics and inorganics. The lobster-eye X-ray optical system imitates the reflective eyes of lobsters, which field of view can be made as large as desired and it is practical to achieve spatial resolution of several millimeters for finite distance detection. A novel lobster-eye X-ray objective is designed based on modifying Schmidt geometry by using multi-lens structure, so as to reduce the difference of resolution between the horizontal and vertical directions. The demonstration experiments of X-ray backscattering imaging were carried out. A suitcase, a wooden box and a tire with several typical samples hidden in them were imaged by the X-ray backscattering inspection system based on a lobster-eye X-ray objective. The results show that this X-ray backscattering inspection system can get a resolution of less than five millimeters under the FOV of more than two hundred millimeters with 0.5 meter object distance, which can still be improved.
Layering of sustained vortices in rotating stratified fluids
NASA Astrophysics Data System (ADS)
Aubert, O.; Le Bars, M.; Le Gal, P.
2013-05-01
The ocean is a natural stratified fluid layer where large structures are influenced by the rotation of the planet through the Coriolis force. In particular, the ocean Meddies are long-lived anticyclonic pancake vortices of Mediterranean origin evolving in the Atlantic Ocean: they have a saltier and warmer core than the sourrounding oceanic water, their diameters go up to 100 km and they can survive for 2 to 3 years in the ocean. Their extensive study using seismic images revealed finestructures surrounding their core (Biescas et al., 2008; Ruddick et al., 2009) corresponding to layers of constant density which thickness is about 40 m and horizontal extent is more than 10 km. These layers can have different origins: salt fingers from a double-diffusive instabilities of salt and heat (Ruddick & Gargett, 2003), viscous overturning motions from a double-diffusive instabilities of salt and momentum (McIntyre, 1970) or global modes of the quasi-geostrophic instability (Nguyen et al., 2011)? As observed by Griffiths & Linden (1981), sustained laboratory anticyclonic vortices created via a continuous injection of isodense fluid in a rotating and linearly stratified layer of salty water are quickly surrounded by layers of constant density. In the continuity of their experiments, we systematically investigated the double-diffusive instability of McIntyre by varying the Coriolis parameter f and the buoyancy frequency N of the background both in experiments and in numerical simulations, and studied the influence of the Schmidt number in numerical simulations. Following McIntyre's approach, typical length and time scales of the instability are well described by a linear stability analysis based on a gaussian model that fits both laboratory and oceanic vortices. The instability appears to be favoured by high Rossby numbers and ratios f/N. We then apply these results to ocean Meddies and conclude about their stability.
A variable turbulent Prandtl and Schmidt number model study for scramjet applications
NASA Astrophysics Data System (ADS)
Keistler, Patrick
A turbulence model that allows for the calculation of the variable turbulent Prandtl (Prt) and Schmidt (Sct) numbers as part of the solution is presented. The model also accounts for the interactions between turbulence and chemistry by modeling the corresponding terms. Four equations are added to the baseline k-zeta turbulence model: two equations for enthalpy variance and its dissipation rate to calculate the turbulent diffusivity, and two equations for the concentrations variance and its dissipation rate to calculate the turbulent diffusion coefficient. The underlying turbulence model already accounts for compressibility effects. The variable Prt /Sct turbulence model is validated and tuned by simulating a wide variety of experiments. Included in the experiments are two-dimensional, axisymmetric, and three-dimensional mixing and combustion cases. The combustion cases involved either hydrogen and air, or hydrogen, ethylene, and air. Two chemical kinetic models are employed for each of these situations. For the hydrogen and air cases, a seven species/seven reaction model where the reaction rates are temperature dependent and a nine species/nineteen reaction model where the reaction rates are dependent on both pressure and temperature are used. For the cases involving ethylene, a 15 species/44 reaction reduced model that is both pressure and temperature dependent is used, along with a 22 species/18 global reaction reduced model that makes use of the quasi-steady-state approximation. In general, fair to good agreement is indicated for all simulated experiments. The turbulence/chemistry interaction terms are found to have a significant impact on flame location for the two-dimensional combustion case, with excellent experimental agreement when the terms are included. In most cases, the hydrogen chemical mechanisms behave nearly identically, but for one case, the pressure dependent model would not auto-ignite at the same conditions as the experiment and the other chemical model. The model was artificially ignited in that case. For the cases involving ethylene combustion, the chemical model has a profound impact on the flame size, shape, and ignition location. However, without quantitative experimental data, it is difficult to determine which one is more suitable for this particular application.
Genetics Home Reference: molybdenum cofactor deficiency
... called molybdenum cofactor. Molybdenum cofactor, which contains the element molybdenum, is essential to the function of several ... Citation on PubMed or Free article on PubMed Central Reiss J, Gross-Hardt S, Christensen E, Schmidt P, ...
Obituary -- Enrique Chavira Navarrete
NASA Astrophysics Data System (ADS)
Carramiñana, A.
2001-04-01
During the twentieth century, Mexican astronomical observatories migrated Tonantzintla and from there to the selected mountain sites of San Pedro Mártir and Cananea. In Tonantzintla Mexican astronomy progressed from cosmography to astrophysics. There, during the fifties and sixties, Guillermo Haro used the Schmidt camera to place México in the astronomical map. Instrumental to this process was Enrique Chavira, whose scientific life almost exactly matched the second half of the century which has just finished, going from the pioneer times of the Tonantzintla Astrophysical Observatory to the fully developed Mexican astronomy of the dawn of the XXI century. Enrique Chavira died unexpectedly 38 days before the turn of the century. Even though his heart had shown past weaknesses, his daily presence in the corridors of the Tonantzintla Institute somehow led us to believe he would always be here. Chavira was the most senior of the astronomers at Tonantzintla and, though he never entered the decision circles, he always had an opinion, frequently ironic, about the main problems of the Instituto. I do remember more than one occasion Alfonso Serrano asking for the advice of Chavira, seeking the experience of the former assistant of Don Guillermo Haro. Born and raised in México City, Chavira eventually moved to Puebla, the closest large city to Tonantzintla, following the steps of Mexican observational astronomy. Without concluding his formal studies, Chavira managed to adjudicate for himself the title of ``astrónomo'', earning it with his skillful handling of the Schmidt camera and the photographic plates. Over the years he took over 8000 astronomical plates, which is a little more than half of the precious Tonantzintla collection. Even though Chavira was aware of his limitations, his ability in photographic astronomy made him a recognized astronomer. The list of his co-authors includes, apart from Guillermo Haro, other renamed astronomers like Manuel Peimbert, Luis Felipe Rodríguez, and Lee Hartmann. He worked in the study of stars with emission lines, flare stars, FU Orionis stars, infrared stars, mainly in in the Tonantzintla plates. Perhaps the closest step to immortality made by Chavira was the co-discovery of comet 1954K which bears the joint name Haro-Chavira, a tacit recognition to the doublet of observers of the golden years of Mexican astronomy. Chavira, witness of the transition from Tacubaya to Tonantzintla, of the overlap of both observatories and the birth of the Instituto Nacional de Astrofísica, óptica y Electrónica, survivor of the hardest times of this institute to see it finally blossom, stood with a calm mixture of humility, enthusiasm and humour. When the interest of the community for the use of Schmidt cameras decayed, when photographic plates were substituted by photoelectronic detectors and the urban light-pollution damaged the skies of Tonantzintla, Chavira went into the careful examination of astronomical plates, dedicating part of his time to attend the frequent visitors who arrive to the ``Observatorio de Tonantzintla''. He proudly showed to the public the Schmidt camera, telling witty anecdotes, often colored with a touch of fantasy. He stayed always close to astronomy and went to the Institute in an almost religious manner until the last day that life allowed him to do so.
Dissolved oxygen transfer to sediments by sweep and eject motions in aquatic environments
O'Connor, B.L.; Hondzo, Miki
2008-01-01
Dissolved oxygen (DO) concentrations were quantified near the sediment-water interface to evaluate DO transfer to sediments in a laboratory recirculating flume and open channel under varying fluid-flow conditions. DO concentration fluctuations were observed within the diffusive sublayer, as defined by the time-averaged DO concentration gradient near the sediment-water interface. Evaluation of the DO concentration fluctuations along with detailed fluid-flow characterizations were used to quantify quasi-periodic sweep and eject motions (bursting events) near the sediments. Bursting events dominated the Reynolds shear stresses responsible for momentum and mass fluctuations near the sediment bed. Two independent methods for detecting bursting events using DO concentration and velocity data produced consistent results. The average time between bursting events was scaled with wall variables and was incorporated into a similarity model to describe the dimensionless mass transfer coefficient (Sherwood number, Sh) in terms of the Reynolds number, Re, and Schmidt number, Sc, which described transport in the flow. The scaling of bursting events was employed with the similarity model to quantify DO transfer to sediments and results showed a high degree of agreement with experimental data. ?? 2008, by the American Society of Limnology and Oceanography, Inc.
NASA Astrophysics Data System (ADS)
Abdelkhalek, M. M.
2009-05-01
Numerical results are presented for heat and mass transfer effect on hydromagnetic flow of a moving permeable vertical surface. An analysis is performed to study the momentum, heat and mass transfer characteristics of MHD natural convection flow over a moving permeable surface. The surface is maintained at linear temperature and concentration variations. The non-linear coupled boundary layer equations were transformed and the resulting ordinary differential equations were solved by perturbation technique [Aziz A, Na TY. Perturbation methods in heat transfer. Berlin: Springer-Verlag; 1984. p. 1-184; Kennet Cramer R, Shih-I Pai. Magneto fluid dynamics for engineers and applied physicists 1973;166-7]. The solution is found to be dependent on several governing parameter, including the magnetic field strength parameter, Prandtl number, Schmidt number, buoyancy ratio and suction/blowing parameter, a parametric study of all the governing parameters is carried out and representative results are illustrated to reveal a typical tendency of the solutions. Numerical results for the dimensionless velocity profiles, the temperature profiles, the concentration profiles, the local friction coefficient and the local Nusselt number are presented for various combinations of parameters.
Direct numerical simulation of incompressible acceleration-driven variable-density turbulence
NASA Astrophysics Data System (ADS)
Gat, Ilana; Matheou, Georgios; Chung, Daniel; Dimotakis, Paul
2015-11-01
Fully developed turbulence in variable-density flow driven by an externally imposed acceleration field, e.g., gravity, is fundamental in many applications, such as inertial confinement fusion, geophysics, and astrophysics. Aspects of this turbulence regime are poorly understood and are of interest to fluid modeling. We investigate incompressible acceleration-driven variable-density turbulence by a series of direct numerical simulations of high-density fluid in-between slabs of low-density fluid, in a triply-periodic domain. A pseudo-spectral numerical method with a Helmholtz-Hodge decomposition of the pressure field, which ensures mass conservation, is employed, as documented in Chung & Pullin (2010). A uniform dynamic viscosity and local Schmidt number of unity are assumed. This configuration encapsulates a combination of flow phenomena in a temporally evolving variable-density shear flow. Density ratios up to 10 and Reynolds numbers in the fully developed turbulent regime are investigated. The temporal evolution of the vertical velocity difference across the shear layer, shear-layer growth, mean density, and Reynolds number are discussed. Statistics of Lagrangian accelerations of fluid elements and of vorticity as a function of the density ratio are also presented. This material is based upon work supported by the AFOSR, the DOE, the NSF GRFP, and Caltech.
NASA Astrophysics Data System (ADS)
Akbar, Noreen Sher; Tripathi, Dharmendra; Khan, Zafar Hayat; Bég, O. Anwar
2016-09-01
In this paper, a mathematical study is conducted of steady incompressible flow of a temperature-dependent viscous nanofluid from a vertical stretching sheet under applied external magnetic field and gravitational body force effects. The Reynolds exponential viscosity model is deployed. Electrically-conducting nanofluids are considered which comprise a suspension of uniform dimension nanoparticles suspended in viscous base fluid. The nanofluid sheet is extended with a linear velocity in the axial direction. The Buonjiornio model is utilized which features Brownian motion and thermophoresis effects. The partial differential equations for mass, momentum, energy and species (nano-particle concentration) are formulated with magnetic body force term. Viscous and Joule dissipation effects are neglected. The emerging nonlinear, coupled, boundary value problem is solved numerically using the Runge-Kutta fourth order method along with a shooting technique. Graphical solutions for velocity, temperature, concentration field, skin friction and Nusselt number are presented. Furthermore stream function plots are also included. Validation with Nakamura's finite difference algorithm is included. Increasing nanofluid viscosity is observed to enhance temperatures and concentrations but to reduce velocity magnitudes. Nusselt number is enhanced with both thermal and species Grashof numbers whereas it is reduced with increasing thermophoresis parameter and Schmidt number. The model is applicable in nano-material manufacturing processes involving extruding sheets.
Solving large-scale dynamic systems using band Lanczos method in Rockwell NASTRAN on CRAY X-MP
NASA Technical Reports Server (NTRS)
Gupta, V. K.; Zillmer, S. D.; Allison, R. E.
1986-01-01
The improved cost effectiveness using better models, more accurate and faster algorithms and large scale computing offers more representative dynamic analyses. The band Lanczos eigen-solution method was implemented in Rockwell's version of 1984 COSMIC-released NASTRAN finite element structural analysis computer program to effectively solve for structural vibration modes including those of large complex systems exceeding 10,000 degrees of freedom. The Lanczos vectors were re-orthogonalized locally using the Lanczos Method and globally using the modified Gram-Schmidt method for sweeping rigid-body modes and previously generated modes and Lanczos vectors. The truncated band matrix was solved for vibration frequencies and mode shapes using Givens rotations. Numerical examples are included to demonstrate the cost effectiveness and accuracy of the method as implemented in ROCKWELL NASTRAN. The CRAY version is based on RPK's COSMIC/NASTRAN. The band Lanczos method was more reliable and accurate and converged faster than the single vector Lanczos Method. The band Lanczos method was comparable to the subspace iteration method which was a block version of the inverse power method. However, the subspace matrix tended to be fully populated in the case of subspace iteration and not as sparse as a band matrix.
57. PLANS OF FOURTH AND FIFTH FLOOR ADDITIONS TO BUILDINGS ...
57. PLANS OF FOURTH AND FIFTH FLOOR ADDITIONS TO BUILDINGS No. 2 and 4, DATED JUNE 24, 1937; SCHMIDT, GARDEN AND ERICKSON, ARCHITECTS - Underwriters' Laboratories, 207-231 East Ohio Street, Chicago, Cook County, IL
Freedom in responsibility: a response.
Waters, Brent
2005-08-01
This paper is a critical response to Elisabeth Gräb-Schmidt's article "Freedom in responsibility: On the relevance of 'sin' as hermeneutic guiding principle in bioethical decision making." Gräb-Schmidt's chief contention is that ethics begins with anthropology, and that moral responsibility is thereby grounded within a set of given limits. Freedom is distorted into sin when these limits are transgressed. My principal complaint is that her account of the relationship between freedom and sin is grounded in a tragic ontology. Alternatively, I contend that anthropology is grounded in Christology in which freedom is a gift of the Spirit. Consequently, sin is not so much tragic as it marks a refusal of humans to accept their divine election. The issues of human cloning and embryonic stem-cell research are used to exemplify what difference these respective differences might make in a process of moral deliberation.
Quantum-correlated two-photon transitions to excitons in semiconductor quantum wells.
Salazar, L J; Guzmán, D A; Rodríguez, F J; Quiroga, L
2012-02-13
The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as well as for unbound electron-hole pairs. We report on the connection between biphoton entanglement, as quantified by the Schmidt number, and absorption by a semiconductor quantum well. Comparison between frequency-anti-correlated, unentangled and frequency-correlated biphoton absorption is addressed. We found that exciton oscillator strengths are highly increased when photons arrive almost simultaneously in an entangled state. Two-photon-absorption becomes a highly sensitive probe of photon quantum correlations when narrow semiconductor quantum wells are used as two-photon absorbers.
Sljivić, M; Smiciklas, I; Plećas, I; Pejanović, S
2011-07-01
The kinetics of Cu2+ sorption on to zeolite, clay and diatomite was investigated as a function of initial metal concentrations. For consideration of the mass transfer phenomena, single resistance models based on both film and intraparticle diffusion were tested and compared. The obtained results suggested that the rate-limiting step in Cu2+ sorption strongly depended on the sorbent type, as well as on initial cation concentration. The decrease in external mass transfer coefficients with the increase in initial metal concentrations was in excellent agreement with expressions based on Sherwood and Schmidt dimensionless numbers. The internal diffusivities through zeolite particles were in the range 1.0 x 10(-11) to 1.0 x 10(-13) m2/min, depending on the Cu2+ concentration and the applied theoretical model.
Quantum entanglement of a harmonic oscillator with an electromagnetic field.
Makarov, Dmitry N
2018-05-29
At present, there are many methods for obtaining quantum entanglement of particles with an electromagnetic field. Most methods have a low probability of quantum entanglement and not an exact theoretical apparatus based on an approximate solution of the Schrodinger equation. There is a need for new methods for obtaining quantum-entangled particles and mathematically accurate studies of such methods. In this paper, a quantum harmonic oscillator (for example, an electron in a magnetic field) interacting with a quantized electromagnetic field is considered. Based on the exact solution of the Schrodinger equation for this system, it is shown that for certain parameters there can be a large quantum entanglement between the electron and the electromagnetic field. Quantum entanglement is analyzed on the basis of a mathematically exact expression for the Schmidt modes and the Von Neumann entropy.
Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)
NASA Astrophysics Data System (ADS)
Smee, Stephen A.; Gunn, James E.; Golebiowski, Mirek; Hope, Stephen C.; Madec, Fabrice; Gabriel, Jean-Francois; Loomis, Craig; Le fur, Arnaud; Dohlen, Kjetil; Le Mignant, David; Barkhouser, Robert; Carr, Michael; Hart, Murdock; Tamura, Naoyuki; Shimono, Atsushi; Takato, Naruhisa
2016-08-01
We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the prime focus. Each spectrograph module has three channels covering wavelength ranges 380 nm - 640 nm, 640 nm - 955 nm, and 955 nm - 1.26 um, with the dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera. The cameras are very large, having a clear aperture of 300 mm at the entrance window, and a mass of 280 kg. In this paper we describe the design of the visible camera cryostats and discuss various aspects of cryostat performance.
VizieR Online Data Catalog: GLASS. VI. MCS J0416.1-2403 HFF imaging & spectra (Hoag+, 2016)
NASA Astrophysics Data System (ADS)
Hoag, A.; Huang, K.-H.; Treu, T.; Bradac, M.; Schmidt, K. B.; Wang, X.; Brammer, G. B.; Broussard, A.; Amorin, R.; Castellano, M.; Fontana, A.; Merlin, E.; Schrabback, T.; Trenti, M.; Vulcani, B.
2017-02-01
The Grism Lens-Amplified Survey from Space (GLASS; GO-13459, PI: Treu; Schmidt+ 2014ApJ...782L..36S; Treu+ 2015, J/ApJ/812/114) observed 10 massive galaxy clusters with the HST WFC3-IR G102 and G141 grism between 2013 December and 2015 January. Each of the clusters targeted by GLASS has deep multi-band HST imaging from the Hubble Frontier Fields (HFF) in 2014 September and/or from CLASH (ESO VIMOS large program CLASH-VLT; 186.A-0798; PI: P. Rosati; Balestra+, 2016, J/ApJS/224/33). We also use mid-IR imaging data acquired with the IRAC on board the Spitzer Space Telescope obtained by the DDT program #90258 (PI: Soifer; P. Capak+ 2016, in prep.) and #80168 (PI: Bouwens). (2 data files).
Rose, Kevin C.; Winslow, Luke A.; Read, Jordan S.; Read, Emily K.; Solomon, Christopher T.; Adrian, Rita; Hanson, Paul C.
2014-01-01
Diel changes in dissolved oxygen are often used to estimate gross primary production (GPP) and ecosystem respiration (ER) in aquatic ecosystems. Despite the widespread use of this approach to understand ecosystem metabolism, we are only beginning to understand the degree and underlying causes of uncertainty for metabolism model parameter estimates. Here, we present a novel approach to improve the precision and accuracy of ecosystem metabolism estimates by identifying physical metrics that indicate when metabolism estimates are highly uncertain. Using datasets from seventeen instrumented GLEON (Global Lake Ecological Observatory Network) lakes, we discovered that many physical characteristics correlated with uncertainty, including PAR (photosynthetically active radiation, 400-700 nm), daily variance in Schmidt stability, and wind speed. Low PAR was a consistent predictor of high variance in GPP model parameters, but also corresponded with low ER model parameter variance. We identified a threshold (30% of clear sky PAR) below which GPP parameter variance increased rapidly and was significantly greater in nearly all lakes compared with variance on days with PAR levels above this threshold. The relationship between daily variance in Schmidt stability and GPP model parameter variance depended on trophic status, whereas daily variance in Schmidt stability was consistently positively related to ER model parameter variance. Wind speeds in the range of ~0.8-3 m s–1 were consistent predictors of high variance for both GPP and ER model parameters, with greater uncertainty in eutrophic lakes. Our findings can be used to reduce ecosystem metabolism model parameter uncertainty and identify potential sources of that uncertainty.
Pearson, W H; Fang, W
2000-10-20
The intramolecular capture of benzocyclobutyl, benzocyclopentyl, and benzocyclohexyl carbocations 7 by azides produces spirocyclic aminodiazonium ions 8, which undergo 1,2-C-to-N rearrangement with loss of dinitrogen to produce benzo-fused iminium ions resulting from either aryl (9) or alkyl (10) migration to the electron-deficient nitrogen atom. Reduction of the iminium ions affords regioisomeric benzo-fused 1-azabicyclo[m.n.0]alkanes, e.g., benzopyrrolizidines, benzoindolizidines, benzoquinolizidines, or perhydrobenzo[f]pyrrolo[1,2-a]azepines in two regioisomeric versions, anilines (e.g., 11-14) and benzylic amines (e.g., 15-18), the result of aryl and alkyl migrations, respectively. Generally, aryl migration is preferred, despite modeling that shows that the lowest energy aminodiazonium ions are those where the departing dinitrogen is preferentially antiperiplanar to the migrating alkyl group rather than the aryl group. The utility of this methodology was illustrated by a formal synthesis of the alkaloid gephyrotoxin 4. A dependence on the efficiency and regioselectivity of the Schmidt reaction upon subtle changes in the structure of the cation precursor was observed, necessitating the exploration of a variety of substrates. Fortunately, these materials were easily made. Ultimately, the azido-alkene 81 bearing a 2-bromoethyl side-chain was useful for the Schmidt reaction, producing the known benzo-fused indolizidine 49, which had been transformed by Ito et al. into gephyrotoxin 4. The synthesis of 49 required nine steps (five purifications) from commercially available 4-methoxy-1-indanone 60 and proceeded in 22% overall yield.
60. FIFTH FLOOR PLAN, SECTIONS AND DETAILS OF 1937 ADDITION ...
60. FIFTH FLOOR PLAN, SECTIONS AND DETAILS OF 1937 ADDITION TO BUILDINGS No. 2 and 4, DATED JUNE 24, 1937: SCHMIDT, GARDEN AND ERICKSON, ARCHITECTS - Underwriters' Laboratories, 207-231 East Ohio Street, Chicago, Cook County, IL
58. SECTION AND DETAILS OF FOURTH AND FIFTH FLOOR ADDITIONS ...
58. SECTION AND DETAILS OF FOURTH AND FIFTH FLOOR ADDITIONS TO BUILDINGS NO. 2 AND 4, DATED JUNE 24, 1937; SCHMIDT, GARDEN AND ERICKSON, ARCHITECTS - Underwriters' Laboratories, 207-231 East Ohio Street, Chicago, Cook County, IL
59. FOURTH FLOOR PLAN, SECTIONS AND DETAILS OF 1937 ADDITION ...
59. FOURTH FLOOR PLAN, SECTIONS AND DETAILS OF 1937 ADDITION TO BUILDINGS NO. 2 and 4, DATED JUNE 24, 1937; SCHMIDT, GARDEN AND ERICKSON, ARCHITECTS - Underwriters' Laboratories, 207-231 East Ohio Street, Chicago, Cook County, IL
Genetics Home Reference: Birt-Hogg-Dubé syndrome
... B, Schmidt LS. Expression of Birt-Hogg-Dubé gene mRNA in normal and neoplastic human tissues. Mod Pathol. 2004 Aug;17(8):998-1011. ... are genome editing and CRISPR-Cas9? What is precision medicine? What ...
Draft Analyses of PM Data for the PM NAAQS Review
These files document all analyses conducted in association with the EPA memorandum from Mark Schmidt, David Mintz, Tesh Rao, and Lance McCluney titled Draft Analyses of PM Data for the PM NAAQS Review, January 31, 2005.
Extended Schmidt law holds for faint dwarf irregular galaxies
NASA Astrophysics Data System (ADS)
Roychowdhury, Sambit; Chengalur, Jayaram N.; Shi, Yong
2017-12-01
Context. The extended Schmidt law (ESL) is a variant of the Schmidt which relates the surface densities of gas and star formation, with the surface density of stellar mass added as an extra parameter. Although ESL has been shown to be valid for a wide range of galaxy properties, its validity in low-metallicity galaxies has not been comprehensively tested. This is important because metallicity affects the crucial atomic-to-molecular transition step in the process of conversion of gas to stars. Aims: We empirically investigate for the first time whether low metallicity faint dwarf irregular galaxies (dIrrs) from the local universe follow the ESL. Here we consider the "global" law where surface densities are averaged over the galactic discs. dIrrs are unique not only because they are at the lowest end of mass and star formation scales for galaxies, but also because they are metal-poor compared to the general population of galaxies. Methods: Our sample is drawn from the Faint Irregular Galaxy GMRT Survey (FIGGS) which is the largest survey of atomic hydrogen in such galaxies. The gas surface densities are determined using their atomic hydrogen content. The star formation rates are calculated using GALEX far ultraviolet fluxes after correcting for dust extinction, whereas the stellar surface densities are calculated using Spitzer 3.6 μm fluxes. The surface densities are calculated over the stellar discs defined by the 3.6 μm images. Results: We find dIrrs indeed follow the ESL. The mean deviation of the FIGGS galaxies from the relation is 0.01 dex, with a scatter around the relation of less than half that seen in the original relation. In comparison, we also show that the FIGGS galaxies are much more deviant when compared to the "canonical" Kennicutt-Schmidt relation. Conclusions: Our results help strengthen the universality of the ESL, especially for galaxies with low metallicities. We suggest that models of star formation in which feedback from previous generations of stars set the pressure in the interstellar medium and affect ongoing star formation, are promising candidates for explaining the ESL. We also confirm that ESL is an independent relation and not a form of a relation between star formation efficiency and metallicity.
NASA Astrophysics Data System (ADS)
Ryu, Junghee; Marciniak, Marcin; Wieśniak, Marcin; Żukowski, Marek
2018-04-01
We generalize a new approach to entanglement conditions for light of undefined photons numbers given in Żukowski et al (2017 Phys. Rev. A 95 042113) for polarization correlations to a broader family of interferometric phenomena. Integrated optics allows one to perform experiments based upon multiport beamsplitters. To observe entanglement effects one can use multi-mode parametric down-conversion emissions. When the structure of the Hamiltonian governing the emissions has (infinitely) many equivalent Schmidt decompositions into modes (beams), one can have perfect EPR-like correlations of numbers of photons emitted into ‘conjugate modes’ which can be monitored at spatially separated detection stations. We provide entanglement conditions for experiments involving three modes on each side, and three-input-three-output multiport beamsplitters, and show their violations by bright squeezed vacuum states. We show that a condition expressed in terms of averages of observed rates is a much better entanglement indicator than a related one for the usual intensity variables. Thus, the rates seem to emerge as a powerful concept in quantum optics, especially for fields of undefined intensities.
POEMMA (Probe Of Extreme Multi-Messenger Astrophysics) Science and Design
NASA Astrophysics Data System (ADS)
Olinto, Angela V.; Perkins, Jeremy S.; POEMMA Collaboration
2018-01-01
In this poster we describe the preliminary design of POEMMA (Probe Of Extreme Multi-Messenger Astrophysics). The two satellites flying in formation consists of an innovative Schmidt telescope design optimized for low energy threshold and large geometry factor for observations. The 4 meter mirror was designed to fit in a dual manifest launch vehicle. A novel corrector lens and fast optics are design to optimized the full field of view to 45 degrees. The large focal surface will be populated by two systems: a multi-anode PMT (MAPMT) array for fluorescence detection and a Silicon PM (SiPM) array for Cherenkov detection around the limb of the Earth. At an altitude of 525 km, the LEO orbit will have a 28.5o inclination the mission can be launched from KSC and have a mission life of 3 years with a 5 year goal. The mission will improve by orders of magnitude the observations of ultra-high energy cosmic rays above tens of EeV and search for neutrinos above tens of PeVs.
A CCD Spectrometer for One Dollar
NASA Astrophysics Data System (ADS)
Beaver, J.; Robert, D.
2011-09-01
We describe preliminary tests on a very low-cost system for obtaining stellar spectra for instructional use in an introductory astronomy laboratory. CCD imaging with small telescopes is now commonplace and relatively inexpensive. Giving students direct experience taking stellar spectra, however, is much more difficult, and the equipment can easily be out of reach for smaller institutions, especially if one wants to give the experience to large numbers of students. We have performed preliminary tests on an extremely low-cost (about $1.00) objective grating that can be coupled with an existing CCD camera or commercial digital single-lens reflex (DSLR) camera and a small telescope typical of introductory astronomy labs. With this equipment we believe it is possible for introductory astronomy students to take stellar spectra that are of high enough quality to distinguish between many MK spectral classes, or to determine standard B and V magnitudes. We present observational tests of this objective grating used on an 8" Schmidt-Cassegrain with a low-end, consumer DSLR camera. Some low-cost strategies for reducing the raw data are compared, with an eye toward projects ranging from individual undergraduate research projects to use by many students in a non-majors introductory astronomy lab. Toward this end we compare various trade offs between complexity of the observing and data reduction processes and the usefulness of the final results. We also describe some undergraduate astronomy education projects that this system could potentially be used for. Some of these projects could involve data-sharing collaborations between students at different institutions.
How Much Dust Does Enceladus eject?
NASA Astrophysics Data System (ADS)
Kempf, S.; Southworth, B.; Srama, R.; Schmidt, J.; Postberg, F.
2016-12-01
There is an ongoing argument how much dust per second the ice volcanoes on Saturn's ice moon eject. By adjusting their plume model to the dust flux measured by the Cassini dust detector during the close Enceladus flyby in 2005, Schmidt et al. (2008) obtained a total dust production rate in the plumes of about 5 kg/s. On the other hand, Ingersoll and Ewald (2005) derived a dust production rate of 51 kg/s from the total plume brightness. Knowledge of the production rate is essential for estimating the dust to gas mass ratio, which in turn is an important constraint for finding the plume source mechanism. Here we report on measurements of the plume dust density during the last close Cassini flyby at Enceladus in October 2015. The data match our numerical model for the Enceladus plume. The model is based on a large number of dynamical simulations including gravity and Lorentz force to investigate the earliest phase of the ring particle life span. The evolution of the electrostatic charge carried by the initially uncharged grains is treated self-consistently. Our numerical simulations reproduce all Enceladus data sets obtained by Cassini's Cosmic Dust Analyzer (CDA). Our model calculations together with the new density data constrain the Enceladus dust source rate to < 5 kg/s. Based on our simulation results we are able to draw conclusions about the emission of plume particles along the fractures in the south polar terrain.
Some new astronomical facilities in China
NASA Astrophysics Data System (ADS)
Wang, Shouguan
1989-10-01
For the 1990's, plans for some astronomical facilities and related research are being carried out in China. This report describes in some detail plans for radio astronomical facilities, a 150/220 cm Schmidt telescope, and experiments on a porcelain mirror material.
Analyses of 2000-2002 PM Data for the PM NAAQS Review
These files document all analyses conducted in association with the EPA memorandum from Mark Schmidt, David Mintz, Tesh Rao, and Lance McCluney titled Analyses of 2000-2002 PM Data for the PM NAAQS Review, August 29, 2003.
2013-09-12
The image taken by the Oschin Schmidt Telescope, shows the star AC +79 3888, also known as Gliese 445. NASA Voyager 1 spacecraft, which is on a trajectory out of our solar system, is headed toward an encounter with AC +79 3888 circled in red.
Gram-Schmidt Orthogonalization by Gauss Elimination.
ERIC Educational Resources Information Center
Pursell, Lyle; Trimble, S. Y.
1991-01-01
Described is the hand-calculation method for the orthogonalization of a given set of vectors through the integration of Gaussian elimination with existing algorithms. Although not numerically preferable, this method adds increased precision as well as organization to the solution process. (JJK)
NASA Astrophysics Data System (ADS)
Bug, Jan; Mosimann, Thomas
2013-04-01
Since 2000 water erosion has been surveyed on 400 ha arable land in three different regions of Lower Saxony (Mosimann et al. 2009). The results of this long-term survey are used for the validation of the soil erosion models such as USLE and Erosion 3D. The validation of the physically-based model Erosion 3D (Schmidt & Werner 2000) is possible because the survey analyses the effects (soil loss, sediment yield, deposition on site) of single thunder storm events and also maps major factors of soil erosion (soil, crop, tillage). A 12.5 m Raster DEM was used to model the soil erosion events.Rainfalldata was acquired from climate stations. Soil and landuse parameters were derived from the "Parameterkatalog Sachsen"(Michael et al. 1996). During thirteen years of monitoring, high intensity storms fell less frequently than expected. High intensity rainfalls with a return period of five or ten years usually occurred during periods of maximum plant cover.Winter events were ruled out because dataon snow melt and rainfallwere not measured. The validation is therefore restricted to 80 events. The validation consists of three parts. The first part compares the spatial distribution of the mapped soil erosion with the model results. The second part calculates the difference in the amount of redistributed soil. The third part analyses off-site effects such as sediment yield and pollution of water bodies. The validation shows that the overall result of erosion 3D is quite good. Spatial hotspots of soil erosion and of off-site effects are predicted correctly in most cases. However, quantitative comparison is more problematic, because the mapping allows only the quantification of rillerosion and not of sheet erosion. So as a rule,the predicted soil loss is higher than the mapped. The prediction of rill development is also problematic. While the model is capable of predicting rills in thalwegs, the modelling of erosion in tractor tracks and headlands is more complicated. In order to obtain better results, the DEM needs a higher resolution, and soil and landuse parameters have to been optimized in tractor tracks and headlands (higher bulk density, less coverage). Other models like LINERO (Bug &Mosimann 2012) can help to get an overview over the location of erosion forms and the soil loss due to rill erosion. References: Bug J., & T. Mosimann (2012): Modellierung der linearen Bodenerosion. Entwicklung eines entscheidungsbasierten Modells zur flächenhaften Prognose der linearen Erosionsaktivität, Geosynthesis 15, Hannover, 105 S. Michael, A., Schmidt, J. & W. A. Schmidt (1996): EROSION 2D/3D - Ein Computermodell zur Simulation der Bodenerosion durch Wasser. Parameterkatalog Sachsen, Freiberg. Mosimann, T., Bug, J. Sanders, S. & F. Beisiegel (2009): Bodenerosionsdauerbeobachtung in Niedersachsen 2000-2008. Methodik, Erosionsgeschehen, Bodenabträge und Anwendung der Ergebnisse, Geosynthesis 14, Hannover, 101 S. Schmidt, J., & M. v. Werner (2000): Modeling sediment and heavy metal yields of drinking water reservoirs in the Osterzgebirge region of Saxony (Germany). In: Schmidt, J. (Ed.), Soil Erosion—Application of Physically Based Models. Springer, Berlin, Heidelberg, New York, pp. 93- 108.
Liberal Education and Social Justice: Some Reflections.
ERIC Educational Resources Information Center
Schaefer, David Lewis
1986-01-01
A discussion of the nature of the relationship between liberal education and social justice looks at two diverse contemporary views, those of Benno Schmidt, Jr. and Bruce Ackerman, and contrasts them with the classical conception of the nature and function of education. (MSE)
Observation of Young Stars at the University Observatory Jena
NASA Astrophysics Data System (ADS)
Berndt, A.; Errmann, R.; Maciejewski, G.; Raetz, St.; Marka, C.; Ginski, Ch.; Mugrauer, M.; Schmidt, T. O. B.; Neuhäuser, R.; Seeliger, M.; Moualla, M.; Pribulla, T.; Hohle, M. M.; Tetzlaff, N.; Adam, Ch.; Eisenbeiss, T.; YETI Team
2011-12-01
We report on observation and determination of rotational and orbital periods of young stars and eclipsing binaries in the young open cluster Trumpler 37. Observations were carried out with the "Schmidt-Teleskop-Kamera" (STK) at University Observatory Jena in 2009 and 2010.
1976-11-01
34Acoustic Thermometric Measurements of Propellant Gas Temperatures in Guns," BRL Report 1919, U.S. Army Ballistic Research Laboratory, Aberdeen...M. Schmidt, E. J. Gion, and D. D. Shear, "Acoustic Thermometric Measurements of Propellant Gas Temperatures in Guns," BRL Report 1919, U.S. Army
DOT National Transportation Integrated Search
1975-01-01
Scores on the American Optical Company (AOC) test (1965 edition), Dvorine test, Farnsworth Lantern test, Color Threshold Tester, Farnsworth-Munsell 100-Hue test, Farnsworth Panel D-15 test, and Schmidt-Haensch Anomaloscope were obtained from 137 men ...
Compressive Sensing for DoD Sensor Systems
2012-11-01
Schmidt (1963) [45] indicated a cosmologically distant, extremely luminous object, the first example of a quasar - an accretion-powered black hole at...evaluating cosmological models and for determining key cos- mological parameters. Sparsity up to the m-degeneracy is independent of the choice of
ERIC Educational Resources Information Center
Poliakoff, Anne Rogers, Ed.
2001-01-01
This theme issue of "Basic Education" considers the importance of studying and comparing student work and educational practice in different countries, in particular as a vehicle to further the professional development of teachers. The first article, "International Studies of Education: Why Should We Care?" (William H. Schmidt;…
1990-04-06
Andrasfalvy 2 Pecs Zoltan Trombitas Sandor Szeles Mrs. Kaposi, Dr. -Andras Pap Sandor Gyulai; Maria Dunai Jozsef Kuller; Dr. Istvan Marton 3 Pecs Dr. Andrea ...Csizmadia Mrs. Szabo, Erzsebet Kovacs 5 Varpalota Peter Patonai Laszlo Czifra Janos Csovari Janos Kovacs Ferenc Schmidt Tibor Fakasz 6 Veszprem -Ferenc
Teaching Tolerance Magazine, 2003.
ERIC Educational Resources Information Center
Carnes, Jim, Ed.
2003-01-01
This magazine provides teachers with classroom learning materials to help children learn to be tolerant with others. Articles in the magazine are: "A Standard to Sustain" (Mary M. Harrison); "Let's Just Play" (Janet Schmidt); "Who's Helen Keller?" (Ruth Shagoury Hubbard); "Margins of Error" (Joe Parsons);…
NASA Astrophysics Data System (ADS)
Wiener, C.; Miller, A.; Zykov, V.
2016-12-01
Advanced robotic vehicles are increasingly being used by oceanographic research vessels to enable more efficient and widespread exploration of the ocean, particularly the deep ocean. With cutting-edge capabilities mounted onto robotic vehicles, data at high resolutions is being generated more than ever before, enabling enhanced data collection and the potential for broader participation. For example, high resolution camera technology not only improves visualization of the ocean environment, but also expands the capacity to engage participants remotely through increased use of telepresence and virtual reality techniques. Schmidt Ocean Institute is a private, non-profit operating foundation established to advance the understanding of the world's oceans through technological advancement, intelligent observation and analysis, and open sharing of information. Telepresence-enabled research is an important component of Schmidt Ocean Institute's science research cruises, which this presentation will highlight. Schmidt Ocean Institute is one of the only research programs that make their entire underwater vehicle dive series available online, creating a collection of video that enables anyone to follow deep sea research in real time. We encourage students, educators and the general public to take advantage of freely available dive videos. Additionally, other SOI-supported internet platforms, have engaged the public in image and video annotation activities. Examples of these new online platforms, which utilize citizen scientists to annotate scientific image and video data will be provided. This presentation will include an introduction to SOI-supported video and image tagging citizen science projects, real-time robot tracking, live ship-to-shore communications, and an array of outreach activities that enable scientists to interact with the public and explore the ocean in fascinating detail.
Exciton absorption of entangled photons in semiconductor quantum wells
NASA Astrophysics Data System (ADS)
Rodriguez, Ferney; Guzman, David; Salazar, Luis; Quiroga, Luis; Condensed Matter Physics Group Team
2013-03-01
The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as well as for unbound electron-hole pairs. We report on the connection between biphoton entanglement, as quantified by the Schmidt number, and absorption by a semiconductor quantum well. Comparison between frequency-anti-correlated, unentangled and frequency-correlated biphoton absorption is addressed. We found that exciton oscillator strengths are highly increased when photons arrive almost simultaneously in an entangled state. Two-photon-absorption becomes a highly sensitive probe of photon quantum correlations when narrow semiconductor quantum wells are used as two-photon absorbers. Research funds from Facultad de Ciencias, Universidad de los Andes
Temporal Multimode Storage of Entangled Photon Pairs
NASA Astrophysics Data System (ADS)
Tiranov, Alexey; Strassmann, Peter C.; Lavoie, Jonathan; Brunner, Nicolas; Huber, Marcus; Verma, Varun B.; Nam, Sae Woo; Mirin, Richard P.; Lita, Adriana E.; Marsili, Francesco; Afzelius, Mikael; Bussières, Félix; Gisin, Nicolas
2016-12-01
Multiplexed quantum memories capable of storing and processing entangled photons are essential for the development of quantum networks. In this context, we demonstrate and certify the simultaneous storage and retrieval of two entangled photons inside a solid-state quantum memory and measure a temporal multimode capacity of ten modes. This is achieved by producing two polarization-entangled pairs from parametric down-conversion and mapping one photon of each pair onto a rare-earth-ion-doped (REID) crystal using the atomic frequency comb (AFC) protocol. We develop a concept of indirect entanglement witnesses, which can be used as Schmidt number witnesses, and we use it to experimentally certify the presence of more than one entangled pair retrieved from the quantum memory. Our work puts forward REID-AFC as a platform compatible with temporal multiplexing of several entangled photon pairs along with a new entanglement certification method, useful for the characterization of multiplexed quantum memories.
Vitrinite equivalent reflectance of Silurian black shales from the Holy Cross Mountains, Poland
NASA Astrophysics Data System (ADS)
Smolarek, Justyna; Marynowski, Leszek; Spunda, Karol; Trela, Wiesław
2014-12-01
A number of independent methods have been used to measure the thermal maturity of Silurian rocks from the Holy Cross Mountains in Poland. Black shales are characterized by diverse TOC values varying from 0.24-7.85%. Having calculated vitrinite equivalent reflectance using three different formulas, we propose that the most applicable values for the Silurian rocks are those based on Schmidt et al. (2015) equation. Based on this formula, the values range from % 0.71 VReqvVLR (the vitrinite equivalent reflectance of the vitrinite-like macerals) to % 1.96 VReqvVLR. Alternative, complementary methods including Rock Eval pyrolysis and parameters based on organic compounds (CPI, Pr/n-C17, Ph/n-C18, MPI1, and MDR) from extracts did not prove adequate as universal thermal maturity indicators. We have confirmed previous suggestions that Llandovery shales are the most likely Silurian source rocks for the generation of hydrocarbons in the HCM.
Adaption from LWIR to visible wavebands of methods to describe the population of GEO belt debris
NASA Astrophysics Data System (ADS)
Meng, Kevin; Murray-Krezan, Jeremy; Seitzer, Patrick
2018-05-01
Prior efforts to characterize the number of GEO belt debris objects by statistically analyzing the distribution of debris as a function of size have relied on techniques unique to infrared measurements of the debris. Specifically the infrared measurement techniques permitted inference of the characteristic size of the debris. This report describes a method to adapt the previous techniques and measurements to visible wavebands. Results will be presented using data from a NASA optical, visible band survey of objects near the geosynchronous orbit, GEO belt. This survey used the University of Michigan's 0.6-m Curtis-Schmidt telescope, Michigan Orbital DEbris Survey Telescope (MODEST), located at Cerro Tololo Inter-American Observatory in Chile. The system is equipped with a scanning CCD with a field of view of 1.6°×1.6°, and can detect objects smaller than 20 cm diameter at GEO.
NASA Astrophysics Data System (ADS)
Bekas, C.; Curioni, A.
2010-06-01
Enforcing the orthogonality of approximate wavefunctions becomes one of the dominant computational kernels in planewave based Density Functional Theory electronic structure calculations that involve thousands of atoms. In this context, algorithms that enjoy both excellent scalability and single processor performance properties are much needed. In this paper we present block versions of the Gram-Schmidt method and we show that they are excellent candidates for our purposes. We compare the new approach with the state of the art practice in planewave based calculations and find that it has much to offer, especially when applied on massively parallel supercomputers such as the IBM Blue Gene/P Supercomputer. The new method achieves excellent sustained performance that surpasses 73 TFLOPS (67% of peak) on 8 Blue Gene/P racks (32 768 compute cores), while it enables more than a two fold decrease in run time when compared with the best competing methodology.
Extinction map of Chamaeleon I molecular cloud with DENIS star counts.
NASA Astrophysics Data System (ADS)
Cambresy, L.; Epchtein, N.; Copet, E.; de Batz, B.; Kimeswenger, S.; Le Bertre, T.; Rouan, D.; Tiphene, D.
1997-08-01
Massive, large scale star counts in the J (1.25μm) band provided by the Deep Near Infrared Survey of the Southern Sky (DENIS) are used for the first time to draw out an extinction map of the Chamaeleon I dark cloud. We derived a 2' resolution map of the cloud from J star counts within an area of 1.5°x3° around the centre of the cloud using an adaptive grid method and applying a wavelet decomposition. Possible contaminating young stellar objects within the cloud are removed, although they are shown to have a negligible effect on the counts. A comparison of our extinction map with the cold contribution of the IRAS 100μm emission shows an almost perfect matching. It is shown that J star counts supersede optical counts on Schmidt plate where A_V_>4.
Not even wrong: A philosophical, historical and ultimately a scientific inquiry into the Schmidt Law
NASA Astrophysics Data System (ADS)
Madore, Barry F.; Carlson, Erika K.
2017-03-01
We introduce a novel approach to interpreting the well-known spatial correlation of gas densities with on-going star formation. Treated as a closed-loop process involving two physically distinct phases the data can be subdivided into regions that are active and those that are quiescent. The active regions can be distinguished by the presence of high-mass, short-lived, but recently-formed OB stars; the quiescent regions are marked by an absence of these stars and they are considered to be recovering from the last star-formation event and are re-collapsing. The relative (areal) frequencies of those two phases are directly proportional to the relative timescales. For four Local Group galaxies, NGC 6822, the Large & Small Magellanic Clouds, and M33, the cloud assembly/collapse timescales are all found to be monotonically decreasing power-law functions of density, with as yet to be explained differences.
Division Viii: Galaxies and the Universe
NASA Astrophysics Data System (ADS)
Sadler, Elaine M.; Combes, Françoise; Okamura, Sadanori; Davies, Roger L.; Gallagher, John S.; Padmanabhan, Thanu; Schmidt, Brian P.
2012-04-01
The fields of extragalactic research and cosmology have continued to progress rapidly over the past three years, as detailed in the reports of the Commission Presidents, and we are pleased to acknowledge the award of the 2011 Nobel Prize in Physics to Saul Perlmutter, Brian P. Schmidt and Adam G. Riess for ``the discovery of the accelerating expansion of the Universe through observations of distant supernovae''. The Gruber Cosmology Prize was awarded in 2009 to Wendy L. Freedman, Robert C. Kennicutt and Jeremy Mould for their leadership of the Hubble Space Telescope Key Project on the Extragalactic Distance Scale, in 2010 to Charles Steidel for the identification and study of galaxies in the very distant universe, and in 2011 to Marc Davis, George Efstathiou, Carlos Frenk and Simon D.M. White for pioneering the use of numerical simulations as a tool to model and interpret the large-scale distribution of galaxies and dark matter.
Research of remote control for Chinese Antarctica Telescope based on iridium satellite communication
NASA Astrophysics Data System (ADS)
Xu, Lingzhe; Yang, Shihai
2010-07-01
Astronomers are ever dreaming of sites with best seeing on the Earth surface for celestial observation, and the Antarctica is one of a few such sites only left owing to the global air pollution. However, Antarctica region is largely unaccessible for human being due to lacking of fundamental living conditions, travel facilities and effective ways of communication. Worst of all, the popular internet source as a general way of communication scarcely exists there. Facing such a dilemma and as a solution remote control and data transmission for telescopes through iridium satellite communication has been put forward for the Chinese network Antarctic Schmidt Telescopes 3 (AST3), which is currently under all round research and development. This paper presents iridium satellite-based remote control application adapted to telescope control. The pioneer work in China involves hardware and software configuration utilizing techniques for reliable and secure communication, which is outlined in the paper too.
Coupling of Waves, Turbulence and Thermodynamics Across the Marginal Ice Zone
2015-09-30
1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Coupling of Waves, Turbulence and Thermodynamics across...developing Thermodynamically Forced Marginal Ice Zone. Submitted to JGR. Heiles,A. S., NPS thesis, Sep. 2014 Schmidt, B. K., NPS thesis March 2012 Shaw
USDA-ARS?s Scientific Manuscript database
Structured illumination using sinusoidal patterns has been utilized for optical imaging of biological tissues in biomedical research and, of horticultural products. Implementation of structured-illumination imaging relies on retrieval of amplitude images, which is conventionally achieved by a phase-...
ERIC Educational Resources Information Center
Fink, Dean
2013-01-01
Invitational theory presents the concept of invitations as related to five factors: people, places, policies, programs, and processes (Purkey & Schmidt, 1990). In this article, the author proposes the addition of a sixth "P," politics. The assumption is that without addressing the political aspect of schools and school systems,…
Enhancing Decision Topology Assessment in Engineering Design
2014-04-10
in engineering design decision making. References 1. Clemen , R. T., 1997, Making Hard Decisions, Second Edition, Duxbury Press. 2. Hazelrigg, G. A...United Kingdom. 6. Lewis, K., Chen, W. and L. C. Schmidt , Editors, 2006, Decision Making in Engineering Design, ASME Press, New York. 7. Myers
Dynamics of entanglement and the Schmidt gap in a driven light-matter system
NASA Astrophysics Data System (ADS)
Gómez-Ruiz, F. J.; Mendoza-Arenas, J. J.; Acevedo, O. L.; Rodríguez, F. J.; Quiroga, L.; Johnson, N. F.
2018-01-01
The ability to modify light-matter coupling in time (e.g. using external pulses) opens up the exciting possibility of generating and probing new aspects of quantum correlations in many-body light-matter systems. Here we study the impact of such a pulsed coupling on the light-matter entanglement in the Dicke model as well as the respective subsystem quantum dynamics. Our dynamical many-body analysis exploits the natural partition between the radiation and matter degrees of freedom, allowing us to explore time-dependent intra-subsystem quantum correlations by means of squeezing parameters, and the inter-subsystem Schmidt gap for different pulse duration (i.e. ramping velocity) regimes—from the near adiabatic to the sudden quench limits. Our results reveal that both types of quantities indicate the emergence of the superradiant phase when crossing the quantum critical point. In addition, at the end of the pulse light and matter remain entangled even though they become uncoupled, which could be exploited to generate entangled states in non-interacting systems.
Simulation Studies on Cooling of Cryogenic Propellant by Gas Bubbling
NASA Astrophysics Data System (ADS)
Sandilya, Pavitra; Saha, Pritam; Sengupta, Sonali
Injection cooling was proposed to store cryogenic liquids (Larsen et al. [1], Schmidt [2]). When a non-condensable gas is injected through a liquid, the liquid component would evaporate into the bubble if its partial pressure in the bubble is lower than its vapour pressure. This would tend to cool the liquid. Earlier works on injection cooling was analysed by Larsen et al. [1], Schmidt [2], Cho et al. [3] and Jung et al. [4], considering instantaneous mass transfer and finite heat transfer between gas bubble and liquid. It is felt that bubble dynamics (break up, coalescence, deformation, trajectory etc.) should also play a significant role in liquid cooling. The reported work are based on simple assumptions like single bubble, zero bubble deformation, and no inter-bubble interactions. Hence in this work, we propose a lumped parameter model considering both heat and mass interactions between bubble and the liquid to gain a preliminary insight into the cooling phenomenon during gas injection through a liquid.
Kalman filter approach for uncertainty quantification in time-resolved laser-induced incandescence.
Hadwin, Paul J; Sipkens, Timothy A; Thomson, Kevin A; Liu, Fengshan; Daun, Kyle J
2018-03-01
Time-resolved laser-induced incandescence (TiRe-LII) data can be used to infer spatially and temporally resolved volume fractions and primary particle size distributions of soot-laden aerosols, but these estimates are corrupted by measurement noise as well as uncertainties in the spectroscopic and heat transfer submodels used to interpret the data. Estimates of the temperature, concentration, and size distribution of soot primary particles within a sample aerosol are typically made by nonlinear regression of modeled spectral incandescence decay, or effective temperature decay, to experimental data. In this work, we employ nonstationary Bayesian estimation techniques to infer aerosol properties from simulated and experimental LII signals, specifically the extended Kalman filter and Schmidt-Kalman filter. These techniques exploit the time-varying nature of both the measurements and the models, and they reveal how uncertainty in the estimates computed from TiRe-LII data evolves over time. Both techniques perform better when compared with standard deterministic estimates; however, we demonstrate that the Schmidt-Kalman filter produces more realistic uncertainty estimates.
Reliability of the sliding scale for collecting affective responses to words.
Imbault, C; Shore, D; Kuperman, V
2018-01-25
Warriner, Shore, Schmidt, Imbault, and Kuperman, Canadian Journal of Experimental Psychology, 71; 71-88 (2017) have recently proposed a slider task in which participants move a manikin on a computer screen toward or further away from a word, and the distance (in pixels) is a measure of the word's valence. Warriner, Shore, Schmidt, Imbault, and Kuperman, Canadian Journal of Experimental Psychology, 71; 71-88 (2017) showed this task to be more valid than the widely used rating task, but they did not examine the reliability of the new methodology. In this study we investigated multiple aspects of this task's reliability. In Experiment 1 (Exps. 1.1-1.6), we showed that the sliding scale has high split-half reliability (r = .868 to .931). In Experiment 2, we also showed that the slider task elicits consistent repeated responses both within a single session (Exp. 2: r = .804) and across two sessions separated by one week (Exp. 3: r = .754). Overall, the slider task, in addition to having high validity, is highly reliable.
Pavloudi, Christina; Christodoulou, Magdalini; Mavidis, Michalis
2016-01-01
This paper describes a dataset of macrofaunal organisms associated with the sponge Sarcotragus foetidus Schmidt, 1862, collected by scuba diving from two sampling sites: one in Greece (North Aegean Sea) and one in Cyprus (Levantine Sea). This dataset includes macrofaunal taxa inhabiting the demosponge Sarcotragus foetidus and contributes to the ongoing efforts of the Ocean Biogeographic Information System (OBIS) which aims at filling the gaps in our current knowledge of the world's oceans. This is the first paper, to our knowledge, where the macrofauna associated with S. foetidus from the Levantine Basin is being recorded. In total, 90 taxa were recorded, from which 83 were identified to the species level. Eight of these species are new records for the Levantine Basin. The dataset contains 213 occurrence records, fully annotated with all required metadata. It is accessible at http://lifewww-00.her.hcmr.gr:8080/medobis/resource.do?r=organismic_assemblages_sarcotragus_foetidus_cyprus_greece.
VizieR Online Data Catalog: Variable stars in the M16-M17 field (Maffei+ 1999)
NASA Astrophysics Data System (ADS)
Maffei, P.; Tosti, G.
2013-07-01
The original work was published as a paper book by the Perugia University in 1999. Before that, only the variable stars list (coordinates, classifications, periods, epochs, magnitude ranges) was published (P. Maffei, 1975IBVS..985....1M) The photographic material was discontinuously collected with the two Schmidt telescopes of the Asiago Observatory and with the Schmidt telescope of the Catania Astrophysical Observatory in the years 1961 to 1991. 103a-O without or with filter GG13 and hypersensitized with NH3 or pre-flashed I-N+RG5 were used. Date, JD, exposure time, emulsion/filter combination and the observer for each plate are listed in Table 1 and Table 2. The variable search was carried out with the blink microscope plate comparator of the Asiago Observatory. Details about the history and the reduction of the observational material are given in the "main.htm" file; the digitization was made by Alessandro Nesci. (7 data files).
Many-body localization transition: Schmidt gap, entanglement length, and scaling
NASA Astrophysics Data System (ADS)
Gray, Johnnie; Bose, Sougato; Bayat, Abolfazl
2018-05-01
Many-body localization has become an important phenomenon for illuminating a potential rift between nonequilibrium quantum systems and statistical mechanics. However, the nature of the transition between ergodic and localized phases in models displaying many-body localization is not yet well understood. Assuming that this is a continuous transition, analytic results show that the length scale should diverge with a critical exponent ν ≥2 in one-dimensional systems. Interestingly, this is in stark contrast with all exact numerical studies which find ν ˜1 . We introduce the Schmidt gap, new in this context, which scales near the transition with an exponent ν >2 compatible with the analytical bound. We attribute this to an insensitivity to certain finite-size fluctuations, which remain significant in other quantities at the sizes accessible to exact numerical methods. Additionally, we find that a physical manifestation of the diverging length scale is apparent in the entanglement length computed using the logarithmic negativity between disjoint blocks.
NASA Astrophysics Data System (ADS)
Sharapova, P. R.; Tikhonova, O. V.; Lemieux, S.; Boyd, R. W.; Chekhova, M. V.
2018-05-01
Control over the spectral properties of the bright squeezed vacuum (BSV), a highly multimode nonclassical macroscopic state of light that can be generated through high-gain parametric down conversion, is crucial for many applications. In particular, in several recent experiments BSV is generated in a strongly pumped SU(1,1) interferometer to achieve phase supersensitivity, perform broadband homodyne detection, or tailor the frequency spectrum of squeezed light. In this work, we present an analytical approach to the theoretical description of BSV in the frequency domain based on the Bloch-Messiah reduction and the Schmidt-mode formalism. As a special case we consider a strongly pumped SU(1,1) interferometer. We show that different moments of the radiation at its output depend on the phase, dispersion, and the parametric gain in a nontrivial way, thereby providing additional insights on the capabilities of nonlinear interferometers. In particular, a dramatic change in the spectrum occurs as the parametric gain increases.
NASA Astrophysics Data System (ADS)
Zuccaro Marchi, Alessandro; Gambicorti, Lisa; Simonetti, Francesca; Salinari, Piero; Lisi, Franco; Bursi, Alessandro; Olivier, Massimiliano; Gallieni, Daniele
2017-11-01
This work presents the latest results of new technological concepts for large aperture, lightweight telescopes using thin deployable active mirrors. The study is originally addressed to a spaceborne DIAL (Differential Absorption Lidar) at 935.5 nm for the measurement of water vapour profile in atmosphere, as an output of an ESA contract (whose preliminary results were presented at ICSO 2006). The high versatility of these concepts allows to exploit the presented technology for any project willing to consider large aperture, segmented lightweight telescopes. A possible scientific application is for Ultra High Energy Cosmic Rays detection through the fluorescence traces in atmosphere and diffused Cerenkov signals observation via a Schmidt-like spaceborne LEO telescope with large aperture, wide Field of View (FOV) and low f/#. A technology demonstrator has been manufactured and tested in order to investigate two project critical areas identified during the preliminary design: the performances of the long-stroke actuators used to implement the mirror active control and the mirror survivability to launch. In particular, this breadboard demonstrates at first that the mirror actuators are able to control with the adequate accuracy the surface shape and to recover a deployment error with their long stroke; secondly, the mirror survivability has been demonstrated using an electrostatic locking between mirror and backplane able to withstand without failure a vibration test representative of the launch environment.
NASA Astrophysics Data System (ADS)
Hüffer, Thorsten; Hofmann, Thilo
2016-04-01
Carbon-based nanomaterials (CNM) exhibit unique physico-chemical properties (e.g., large surface area to volume ratios, electron delocalization), which make them promising for a great number of applications. The production, use, and disposal of CNM and CNM-containing products will inevitably result in the release of these materials into the environment. The fate and transport of CNM greatly depends on their physico-chemical properties and surrounding environmental conditions. This field of research has constantly increased over recent years. Yet little is known on how transformation processes such as changes in surface properties or aggregation influence their interaction with other environmental species (i.e., solid surfaces or contaminants). For example, changes in redox chemistry in combination with irradiation have shown to significantly alter the surface chemistry of C60 fullerenes and consequently decreased their sorption affinity towards non-polar organic contaminants [1]. The presence of natural organic matter (NOM) seems to play a major role on the aggregation of CNM; however, the results are not consistent whether this leads to an increase or decrease in interactions with solid surfaces or contaminants. Either increased interactions resulting from a higher dispersion of CNM or decreased interactions of CNM, which was assigned to an offset of "creating" new sorption sites due to increased dispersion by a reduced accessibility of polar moieties. For the latter effect, NOM was proposed to either directly compete for sorption sites on CNM surface or a blocking of CNM pores by large NOM molecules [2]. The potential consequences of these changes in surface properties of CNM on their toxic effects on microorganisms have only been partially examined. For an environmental risk assessment, data on the occurrence of CNM is obligatory but to date the environmental concentrations of CNM are still difficult to assess due to still unsolved analytical issues in matrix separation and the discrimination of CNM from naturally present particles with similar dimensions and properties (e.g., soot or colloids). Recently, progress has been made to characterize the aggregation and to determine the occurrence of (functionalized) fullerenes using asymmetrical flow field-flow fractionation coupled to a LC-HR-MS [3]. In this contribution, the major results during the last decade of environmental research into CNM will be reviewed with the focus on their analyses and characterization, and interactions with solid surfaces. References: [1] Hüffer, T., Kah, M., Hofmann, T., Schmidt, T.C. (2013) How Redox Conditions and Irradiation Affect Sorption of PAHs by Dispersed Fullerenes (nC60). Environmental Science & Technology, 47(13), 6935-6942. [2] Hüffer, T., Schroth, S., Schmidt, T.C. (2015) Influence of humic acids on sorption of alkanes by carbon nanotubes - Implications for the dominant sorption mode. Chemosphere, 119, 1169-1175. [3] Kolkman, A., Emke, E., Bauerlein, P.S., Carboni, A., Tran, D.T., terLaak, T.L., vanWezel, A.P., deVoogt, P. (2013) Analysis of (Functionalized) Fullerenes in Water Samples by Liquid Chromatography Coupled to High-Resolution Mass Spectrometry. Analytical Chemistry, 85(12), 5867-5874.
Modeling In-Vehicle Reaches Perturbed by Ride Motion
2004-03-14
Human Factors and Ergonomics Society, Denver, CO. 13. Schmidt, R.A. (1987) Motor control and learning: A behavioral emphasis, 2nd ed. Human ... Kinetics : Champaign, IL. 14. Sokal, R.R., Rohlf, F.J. (1981) Biometry, Freeman: San Francisco, CA. CONTACT Please use the following contact regarding
An Analysis of Application Generators.
1983-03-01
query language OUEL in the programming language C, THESEUS [20], which embeds relational operators in the language Euclid. Schmidt [21] reports some...34The Design and Implementation of INGRES," ACM-TODS, Vol. 1. No. 3, 1976,. 33 £ 20. Shopiro,J.E., " THESEUS -A Programming Language for Relational
Reflecting Schmidt/Littrow Prism Imaging Spectrometer
NASA Technical Reports Server (NTRS)
Breckinridge, J. B.; Page, N. A.; Shack, R. V.; Shannon, R. R.
1985-01-01
High resolution achieved with wide field of view. Imaging Spectrometer features off-axis reflecting optics, including reflecting "slit" that also serves as field flattener. Only refracting element is prism. By scanning slit across object or scene and timing out signal, both spectral and spatial information in scene are obtained.
Implementing Linear Algebra Related Algorithms on the TI-92+ Calculator.
ERIC Educational Resources Information Center
Alexopoulos, John; Abraham, Paul
2001-01-01
Demonstrates a less utilized feature of the TI-92+: its natural and powerful programming language. Shows how to implement several linear algebra related algorithms including the Gram-Schmidt process, Least Squares Approximations, Wronskians, Cholesky Decompositions, and Generalized Linear Least Square Approximations with QR Decompositions.…
Motor Skill Learning in Children.
ERIC Educational Resources Information Center
Gabbard, Carl P.
The purpose of this article is to briefly describe schema theory and indicate its relevance to early childhood development, with specific reference to children's acquisition of motor skills. Schema theory proposes an explanation of how individuals learn and perform a seemingly endless variety of movements. According to Schmidt (1975), goal…
Girls Disengage from High School Science
ERIC Educational Resources Information Center
Education Digest: Essential Readings Condensed for Quick Review, 2010
2010-01-01
High school girls are bored, disengaged, and stressed in science classes, according to preliminary results of a study led by Northern Illinois University researchers Jennifer Schmidt and M. Cecil Smith. The two professors in the College of Education's Department of Leadership, Educational Psychology, and Foundations studied 244 high school…
The Role of Measurement Error in Familiar Statistics
2006-06-01
Manual of Mental Disorders (3rd ed., revised; American Psychiatric Association, 1987) for the clinical conditions of anorexia nervosa and borderline...borderline personality disorder, anorexia ner’vosa, and a control group. Family Process, 39, 345-358. Hunter, J. E., & Schmidt, F. L. (1976). A critical
United States Navy Oceanic Armed Reconnaissance System
2011-12-12
This report was prepared by: Rahul Petrie Daniel Reese Kurtis Hoots Robert Taylor Drew Nash Bunny Cooper Jonathan Trdan-Schmidt Marshall...NPS – Cohort 311-102S, Team OARS: Mr. Marshall Rice, Mr. Rahul Petrie, Mr. Daniel Reese, Mr. Kurtis Hoots, Mr. Robert Taylor, Mr. Drew Nash
Decision Topology Assessment in Engineering Design Under Uncertainity
2014-01-01
those of the United States Government or the DoA, and shall not be used for advertising or product endorsement purposes. REFERENCES 1. Clemen ...Raiffa, H., 1994, Decisions with Multiple Objectives, Cambridge University Press, Cambridge, United Kingdom. 6. Lewis, K., W. Chen, and L.C. Schmidt
The extension of the INCL model for spallation reactions up to 15 GeV and applications
NASA Astrophysics Data System (ADS)
Pedoux, Sophie
There has been recently a considerable improvement of the intranuclear cascade + evaporation models, triggered by studies of possible transmutation of nuclear wastes in so-called ADS machines. It seems that the best conditions are fulfilled by proton beams of around 1 GeV. It has been shown that the Liege intranuclear cascade model (INCL), developed along these lines, reproduces fairly well a whole bunch of experimental data in the 200 MeV to 2 GeV range [1], when coupled with the ABLA evaporation-fission code developed by K.-H. Schmidt [2]. These data include total reaction cross-section, particle multiplicities, double differential crosssections, residue mass spectrum, isotopic distributions and recoil energy spectra. It should be stressed that this agreement is achieved without adjustment of parameters in the INCL part. Even the stopping time of the cascade is determined self-consistently. We are currently involved in the extension of the INCL4 to make it useful for the study of radiation effects induced by cosmic rays concerning satellite and man-born space mission. For that purpose, we have re-examined the description of inelastic nucleon-nucleon collisions in the 2-20 GeV c.m. energy range. A new model incorporating multipion production without relying on resonances (except for the Delta (1232)resonance), but consistent with known pionemission pattern [3], will be presented. Furthermore, the description of target nuclei relevant for radioprotection issues (like C,O,N) and for material protection (Si) will be improved. The possibility of predicting accurately neutron emission, deposition of energy, radiotoxicity, number of dpa and gas formation with the help of the improved INCL4 are presently tested and will be reported on. [1] A. Boudard, J. Cugnon, S. Leray and C. Volant, Phys. Rev. C66 (2002)044615 [2] J.-J. Gaimard and K.-H. Schmidt, Nucl. Phys. A531(1991) 709 [3] Z. Chen, Int. J. Modern Phys. E, Vol.2 N.2 (1993)285
Effect of hydrogen on the melting of the Fe-C system and the fate of the subducted carbon
NASA Astrophysics Data System (ADS)
Lai, X.; Chen, B.; Gao, J.; Zhu, F.
2017-12-01
The subducted oceanic crust carries significant amount of carbonates and organic carbons from the surface into the deep mantle. Through slab-mantle interactions, subducted carbons can react with metallic iron in the metal-saturated regions of the mantle and form various reduced species such as Fe carbides. The Fe-C system is found to have higher eutectic melting temperature than mantle geotherm and thus carbon by forming iron carbides may be "redox freezed" in the mantle (Rohrbach and Schmidt 2011). Hydrogen was found to be have significant effect on the melting of the Fe-light-elements systems such as the Fe-S system (Shibazaki et al., 2011). Here we report experimental results from both multi-anvil press and diamond anvil cell experiments on the melting behaviors of the Fe-C-H system. C14H12, a solid-state C-H organic compound was used as a C-H source to react with the metallic iron at high pressure and high temperature conditions. With excess C14H12, hydrogen in the FeHx alloy was totally replaced by carbon at 14.8-24.7 GPa. Conversely, with excess Fe, the existence of hydrogen is found to depress the melting temperature of the Fe-C system by at least 100 K. Hydrogen may facilitate the transport and cycling of subducted carbon in the deep mantle and contribute to formation of superdeep diamonds (Smith et al. 2016). Rohrbach, Arno, and Max W. Schmidt. "Redox freezing and melting in the Earth's deep mantle resulting from carbon-iron redox coupling." Nature 472.7342 (2011): 209. Shibazaki, Yuki, et al. "Effect of hydrogen on the melting temperature of FeS at high pressure: Implications for the core of Ganymede." Earth and Planetary Science Letters 301.1 (2011): 153-158. Smith, Evan M., et al. "Large gem diamonds from metallic liquid in Earth's deep mantle." Science 354.6318 (2016): 1403-1405.
NASA Astrophysics Data System (ADS)
Sharon, Chelsea E.; Riechers, Dominik A.; Hodge, Jacqueline; Carilli, Chris L.; Walter, Fabian; Weiß, Axel; Knudsen, Kirsten K.; Wagg, Jeff
2016-08-01
We present CO(1-0) observations obtained at the Karl G. Jansky Very Large Array for 14 z˜ 2 galaxies with existing CO(3-2) measurements, including 11 galaxies that contain active galactic nuclei (AGNs) and three submillimeter galaxies (SMGs). We combine this sample with an additional 15 z˜ 2 galaxies from the literature that have both CO(1-0) and CO(3-2) measurements in order to evaluate differences in CO excitation between SMGs and AGN host galaxies, to measure the effects of CO excitation on the derived molecular gas properties of these populations, and to look for correlations between the molecular gas excitation and other physical parameters. With our expanded sample of CO(3-2)/CO(1-0) line ratio measurements, we do not find a statistically significant difference in the mean line ratio between SMGs and AGN host galaxies as can be found in the literature; we instead find {r}{3,1}=1.03+/- 0.50 for AGN host galaxies and {r}{3,1}=0.78+/- 0.27 for SMGs (or {r}{3,1}=0.90+/- 0.40 for both populations combined). We also do not measure a statistically significant difference between the distributions of the line ratios for these populations at the p = 0.05 level, although this result is less robust. We find no excitation dependence on the index or offset of the integrated Schmidt-Kennicutt relation for the two CO lines, and we obtain indices consistent with N = 1 for the various subpopulations. However, including low-z “normal” galaxies increases our best-fit Schmidt-Kennicutt index to N˜ 1.2. While we do not reproduce correlations between the CO line width and luminosity, we do reproduce correlations between CO excitation and star-formation efficiency.
Optimizing Opto-mechanical Performance Using Simple Tools and Techniques
NASA Astrophysics Data System (ADS)
Krajci, Tom
2009-05-01
You just purchased a modest setup for your observatory - perhaps a mass produced Schmidt-Cassegrain on a German equatorial mount. However, optically and mechanically it's not performing as well as you would like. What can you do? Some simple assessments and repairs may make all the difference. Assessments can be as easy as visual inspection of various mount components, such as the tripod, where gaps between components reduce stiffness or allow unexpected shifts when loads change. Some assessments are only slightly more involved. Main mirror flop can be evaluated by aligning the main telescope and finder on a bright star and then slewing to various parts of the sky. Pointing differences between the two will be readily apparent if this problem exists. Most mid-level mounts use worm drives, but often excessive spacing between worm and worm gear produces large, and unnecessary amounts of backlash. Visual inspection of your dovetail mounting system may leave doubts in your mind as to adequate stiffness. Imaging through the entire night may show you that your aluminum tube telescope causes excessive focus shift as temperature drops. Over time, your Schmidt-Cassegrain corrector plate may no longer be securely held by its retaining ring, and the same may apply to the secondary mirror cell. Repairs for these problems are often not difficult if you're mechanically inclined. Gaps in mount components can be eliminated with shims. Combating mirror flop may be the most difficult task. This can involve re-gluing the main mirror and bolting the main mirror cell in a fixed position. Corrector plate and secondary mirror cells can be improved with setscrews and shims - implementing sound kinematic principles. Worm gear spacing can often be adjusted with simple tools. This brief paper can't possibly cover all problems and solutions, but it can give you the proper mindset to looking at your system with a critical eye and implementing simple, inexpensive fixes. You may be pleasantly surprised by the improvements.
AGN contamination in total infrared determined star formation rates in dusty galaxies at z~2-3
NASA Astrophysics Data System (ADS)
Mazzei, Renato; Sharon, Chelsea E.; Riechers, Dominik
2017-01-01
Along with theoretical work that suggests feedback from active galactic nuclei (AGN) may quench star formation in massive galaxies, the temporal coincidence between the peak of cosmic star formation rates and black hole accretion rates suggests that AGN are common in star forming galaxies at z~2-3. Since star forming galaxies at these epochs are also very dusty, it is important that we correct galaxies’ long-wavelength properties for the presence of dust-obscured AGN in order to accurately capture their star formation rates and gas characteristics. We present a spectral energy distribution (SED) analysis of several un-lensed z~2-3 dusty star-forming galaxies from Pope et al. (2008) and Coppin et al. (2010), which we compare to several other high-z starbursts with well sampled SEDs. We constructed dust SEDs from existing Spitzer, Herschel, and SCUBA-2 photometry catalogues with data between 3.6 and 850 μm. For the SED fits, we used the Code Investigating GALaxy Emission (CIGALE), since it self-consistently determines the dust attenuation of stars and dust emission in the infrared in addition to determining the dust emission from obscured AGN (Noll et al. 2009; Serra et al. 2011). Our best-fit SEDs have typical reduced χ2 values between 0.2 and ~3. We use the output from CIGALE to determine the fraction of the total infrared luminosity (LTIR 8-1000 um) from star formation and from any potential obscured AGN. In order to examine the effects of buried AGN on the integrated Schmidt-Kennicutt relation (log(LTIR) vs. log(L'CO)), we compare our new LTIR to recently obtained CO(1-0) line luminosities from the Karl G. Jansky Very Large Array. Unaccounted for dust emission from AGN can artificially inflate the star formation rate inferred from LTIR, and may therefore offset starburst galaxies from the local Schmidt-Kennicutt relation and increase the slope of the relation, which can affect the inferred drivers of star formation.
On the Kennicutt-Schmidt Relation of Low-Metallicity High-Redshift Galaxies
NASA Astrophysics Data System (ADS)
Gnedin, Nickolay Y.; Kravtsov, Andrey V.
2010-05-01
We present results of self-consistent, high-resolution cosmological simulations of galaxy formation at z ~ 3. The simulations employ a recently developed recipe for star formation based on the local abundance of molecular hydrogen, which is tracked self-consistently during the course of simulation. The phenomenological H2 formation model accounts for the effects of dissociating UV radiation of stars in each galaxy, as well as self-shielding and shielding of H2 by dust, and therefore allows us to explore effects of lower metallicities and higher UV fluxes prevalent in high-redshift galaxies on their star formation. We compare stellar masses, metallicities, and star formation rates of the simulated galaxies to available observations of the Lyman break galaxies (LBGs) and find a reasonable agreement. We find that the Kennicutt-Schmidt (KS) relation exhibited by our simulated galaxies at z ≈ 3 is substantially steeper and has a lower amplitude than the z = 0 relation at ΣH <~ 100 M odot pc-2. The predicted relation, however, is consistent with existing observational constraints for the z ≈ 3 damped Lyα and LBGs. Our tests show that the main reason for the difference from the local KS relation is lower metallicity of the interstellar medium in high-redshift galaxies. We discuss several implications of the metallicity-dependence of the KS relation for galaxy evolution and interpretation of observations. In particular, we show that the observed size of high-redshift exponential disks depends sensitively on their KS relation. Our results also suggest that significantly reduced star formation efficiency at low gas surface densities can lead to strong suppression of star formation in low-mass high-redshift galaxies and long gas consumption time scales over most of the disks in large galaxies. The longer gas consumption time scales could make disks more resilient to major and minor mergers and could help explain the prevalence of the thin stellar disks in the local universe.
Research in Energetic Compounds.
1980-01-01
Copies No. Copies Dr. L.V. Schmidt 1 [r. F. Roberto Assistant Secretary of the Navy Code AFRPL HKPA (R,E, and S) Room 5E 731 Edwards AF6, CA 93523...Force Office of Sciertific Dr. Richard S. Miller 10 Research Office of Naval Research Directorate of Chemical Sciences Arlington, VA 22217 Bolling Air
The ABCs for Pre-Service Teacher Cultural Competency Development
ERIC Educational Resources Information Center
He, Ye; Cooper, Jewell E.
2009-01-01
In an effort to combine pre-service teachers' self-reflection with their field experiences to enhance their cultural competency, this study adopted Schmidt's ABC's (Autobiography, Biography, and Cross-cultural Comparison) Model in two courses in a pre-service teacher education program. Through group comparisons, this study measured the impact that…
Language and Politics in the United States and Canada: Myths and Realities.
ERIC Educational Resources Information Center
Ricento, Thomas, Ed.; Burnaby, Barbara, Ed.
This collection includes the following essays on language and politics in North America: "Respecting the Citizens: Reflections on Language Policy in Canada and the United States" (Colin H. Williams); "The Politics of Language in Canada and the United States: Explaining the Differences" (Ronald Schmidt, Sr.); "Demographic…
Early Identification of Skill Needs in Europe. CEDEFOP Reference Series.
ERIC Educational Resources Information Center
Schmidt, Susanne Liane, Ed.; Schomann, Klaus, Ed.; Tessaring, Manfred, Ed.
This document contains the following papers: "Early Recognition of Skill Needs in Europe: European Conference, Berlin, 30/31 May 2002" (Susanne Liane Schmidt, Klaus Schomann, Manfred Tessaring); "Welcome and Opening of the European Conference 'Early Recognition of Skill Needs in Europe,' 30 May 2002, Social Sciences Research Center…
The Neglected Years: Early Childhood.
ERIC Educational Resources Information Center
Miller, Miriam, Ed.
This collection of articles deals with the plight of preschool children in developing countries and contemporary thought in the field of child care. In "Speaking Freely--Highlights of a Roundtable Discussion on the Preschool Child, with a 'Commentary' by Dr. William M. Schmidt," 18 doctors exchange ideas about the major problems in child…
Spectral Classification in the MK System of 167 Northern HD Stars
NASA Astrophysics Data System (ADS)
Jensen, K. S.
1981-09-01
Spectral classifications in the MK system of 167 northern HD stars are presented. The spectra (102 A/mm at Hγ, width 0.60 mm) are from objective prism plates obtained with the Schmidt telescope of the CUO, Brorfelde. Most of the stars have no previous MK classification.
ERIC Educational Resources Information Center
Schmidt, T.
2016-01-01
The article examines the relevance of compensatory education for educationally disadvantaged children of preschool age in Germany and beyond The article is a shortened, adapted and translated version of the paper Schmidt, T., & Smidt, W. (2014). "Kompensatorische Förderung benachteiligter Kinder--Entwicklungslinien, Forschungsbefunde und…
Authority and Pedagogy as Framing
ERIC Educational Resources Information Center
Schmidt, Patrick
2016-01-01
This article examines the relationship between authority and music. It starts with the proposition that music--as an art or an educative enterprise in Western environs--remains a highly idealized enterprise and this idealization creates an alibi for action that is characteristically narrow and guided by authority. Schmidt claims that authority is…
Measurements on a Circular Plate Immersed in Muzzle Flow
1977-06-01
center of the plate. Six pressure taps 11. E. If. Schmidt, E. J. Gion, and D. D. Shear, "Acoustic Thermometric Measurements of Propellant Gas...Shear, "Acoustic Thermometric Measurements of Propellant Gas Temperatures in Guns," AIAA J., Vol. 15, No. 2, February 1977, pp. 222-226. 38
Journal of Business and Training Education, 2001.
ERIC Educational Resources Information Center
Redmann, Donna H., Ed.
2001-01-01
This volume contains 10 papers, including studies, a literature review, and program descriptions, that are devoted to various aspects of business education and training. The following papers are included: "The Net Generation: What Are We Doing To Meet Their Learning and Training Needs" (Jacqueline J. Schmidt, Kathleen M. Hiemstra);…
Multi-Layered Feedforward Neural Networks for Image Segmentation
1991-12-01
the Gram-Schmidt Network ...................... 80 xi Preface WILLIAM SHAKESPEARE 1564-1616 Is this a dagger which I see before me, The handle toward...any input-output mapping with a single hidden layer of non-linear nodes, the result may be like proving that a monkey could write Hamlet . Certainly it
Teaching Linear Algebra: Proceeding More Efficiently by Staying Comfortably within Z
ERIC Educational Resources Information Center
Beaver, Scott
2015-01-01
For efficiency in a linear algebra course the instructor may wish to avoid the undue arithmetical distractions of rational arithmetic. In this paper we explore how to write fraction-free problems of various types including elimination, matrix inverses, orthogonality, and the (non-normalizing) Gram-Schmidt process.
Bayesian Authentication: Quantifying Security of the Hancke-Kuhn Protocol
2010-01-01
Conference on Advances in Cryptology, pages 169–177, London, UK, 1991. Springer-Verlag. [6] Stefan Brands and David Chaum . Distance-bounding protocols. In...Lecture Notes in Computer Science, pages 371–388. Springer, 2004. [30] Patrick Schaller, Benedikt Schmidt, David Basin, and Srdjan Capkun. Modeling and
... 401. CrossRef PubMed Metzger BE, Lowe LP, Dyer AR, Trimble ER, Chaovarindr U, Coustan DR, et al. ... 805. CrossRef PubMed Schmidt MI, Duncan BB, Sharrett AR, Lindberg G, Savage PJ, Offenbacher S, et al. Markers ...
NASA in Silicon Valley Live - Episode 01 - We're Going Back to the Moon!
2018-01-12
We’ve launched a live video show on Twitch called NASA in Silicon Valley Live! This is our premiere episode streamed on Jan. 12. In it, we talk about going back to the Moon with NASA rock stars Jim Green and Greg Schmidt.
Non-linear optical properties of arylfuranylpropenones
NASA Astrophysics Data System (ADS)
Holla, B. Shivarama; Veerendra, B.; Indira, J.
2003-05-01
A series of arylfuranylpropenones 3a-i were synthesized by the reaction of 5-(2-nitro-4-methoxyphenyl)-2-furfural 1 with various acetophenones 2 by Claisen-Schmidt condensation. All the newly synthesized chalcones were characterized by elemental analysis and spectral studies. Most of them showed SHG conversion efficiency in powder form.
A New In Vitro Model of Breast Cancer Metastasis to Bone
2008-04-01
intravital videomicroscopy [11, 12] have revealed that early stage, pre-angiogenic interactions between the cancer cells and the bone environment are...Chambers AF, MacDonald IC, Schmidt EE, et al. (1995) Steps in tumor metastasis: New concepts from intravital videomicroscopy . 279 - 301 13. Steeg PS
Coherence Properties of Strongly Interacting Atomic Vapors in Waveguides
2011-12-31
lattice in the mean-field regime [22]. There the goal was to repeat, for our system, the Chirikiov-lzrailev program for Fermi- Pasta -Ulam chain and...define a typical deviation from ergodicity), we introduce a geometric structure— based on the Frobenius or Hilbert-Schmidt inner product—to the space of
Investigating Pragmatic Language Learning in Foreign Language Classrooms
ERIC Educational Resources Information Center
Soler, Eva Alcon
2008-01-01
A lot of research addressing learners' development of pragmatics has recently been conducted (Kasper and Schmidt 1996; Bardovi-Harlig, 2002; Kasper and Rose 2002). From this same approach, a review of theoretical perspectives on pragmatic learning and how they have been operationalised in interlanguage pragmatic research is presented. Second, by…
The Cirque du Soleil of Golgi membrane dynamics
2009-01-01
The role of lipid metabolic enzymes in Golgi membrane remodeling is a subject of intense interest. Now, in this issue, Schmidt and Brown (2009. J. Cell Biol. doi:10.1083/jcb.200904147) report that lysophosphatidic acid–specific acyltransferase, LPAAT3, contributes to Golgi membrane dynamics by suppressing tubule formation. PMID:19635838
The Cirque du Soleil of Golgi membrane dynamics.
Bankaitis, Vytas A
2009-07-27
The role of lipid metabolic enzymes in Golgi membrane remodeling is a subject of intense interest. Now, in this issue, Schmidt and Brown (2009. J. Cell Biol. doi:10.1083/jcb.200904147) report that lysophosphatidic acid-specific acyltransferase, LPAAT3, contributes to Golgi membrane dynamics by suppressing tubule formation.
The "Crucified" Leader: Cynicism, Fantasies and Paradoxes in Education
ERIC Educational Resources Information Center
Hansen, Dion Rüsselbaek; Frederiksen, Lars Frode
2017-01-01
In this paper we argue that transnational as well as national political demands and expectations on the educational field are contributing to (re)produce four ideological-based educational leadership discourses in the literature. In order to conceptualize these discourses, we turn to the work of Schmidt ("Diagnosis I--Filosoferende…
The Development of Beginning Mathematics Teacher Pedagogical Content Knowledge
ERIC Educational Resources Information Center
Lannin, John K.; Webb, Matthew; Chval, Kathryn; Arbaugh, Fran; Hicks, Sarah; Taylor, Cynthia; Bruton, Rebecca
2013-01-01
Recent research efforts (Schmidt et al. in "The preparation gap: teacher education for middle school mathematics in six countries," MSU Center for Research in Mathematics and Science Education, 2007) demonstrate that teacher development programs in high-performing countries offer experiences that are designed to develop both mathematical…
Lift Enhancement Using Close-Coupled Canard/Wing Vortex Interaction
1990-12-01
8217M - 4U4 Richard M. Howard, Thesis Advisor Louis V. Schmidt, Second Reader E. Roberts Wood, Chairman Department of Aeronautics and Astronautics ii...Pope, Alan, Low-Speed Wind Tunnel Testing, John Wiley and Sons, Inc., 1984. 19. Raymer , Daniel P., Aircraft Design: a Conceptual Approach, AIAA, Inc
Moving force identification based on modified preconditioned conjugate gradient method
NASA Astrophysics Data System (ADS)
Chen, Zhen; Chan, Tommy H. T.; Nguyen, Andy
2018-06-01
This paper develops a modified preconditioned conjugate gradient (M-PCG) method for moving force identification (MFI) by improving the conjugate gradient (CG) and preconditioned conjugate gradient (PCG) methods with a modified Gram-Schmidt algorithm. The method aims to obtain more accurate and more efficient identification results from the responses of bridge deck caused by vehicles passing by, which are known to be sensitive to ill-posed problems that exist in the inverse problem. A simply supported beam model with biaxial time-varying forces is used to generate numerical simulations with various analysis scenarios to assess the effectiveness of the method. Evaluation results show that regularization matrix L and number of iterations j are very important influence factors to identification accuracy and noise immunity of M-PCG. Compared with the conventional counterpart SVD embedded in the time domain method (TDM) and the standard form of CG, the M-PCG with proper regularization matrix has many advantages such as better adaptability and more robust to ill-posed problems. More importantly, it is shown that the average optimal numbers of iterations of M-PCG can be reduced by more than 70% compared with PCG and this apparently makes M-PCG a preferred choice for field MFI applications.
NASA Astrophysics Data System (ADS)
Zigta, B.; Koya, P. R.
2017-12-01
This paper studies the effect of magneto hydrodynamics on unsteady free convection between a pair of infinite vertical Couette plates. The temperature of the plates and concentration between the plates vary with time. Convection between the plates is considered in the presence of thermal radiation and chemical reaction. The solution is obtained using perturbation techniques. These techniques are used to transform nonlinear coupled partial differential equations to a system of ordinary differential equations. The resulting equations are solved analytically. The solution is expressed in terms of power series with some small parameter. The effect of various parameters, viz., velocity, temperature and concentration, has been discussed. Mat lab code simulation study is carried out to support the theoretical results. The result shows that as the thermal radiation parameter R increases, the temperature decreases near the moving porous plate while it approaches to a zero in the region close to the boundary layer of the stationary plate. Moreover, as the modified Grashof number, i.e., based on concentration difference, increases, the velocity of the fluid flow increases hence the concentration decreases. An increase in both the chemical reaction parameter and Schmidt number results in decreased concentration.
NASA Astrophysics Data System (ADS)
Mickaelian, Areg; Azatyan, Naira; Farmanyan, Sona; Mikayelyan, Gor
2016-10-01
Armenia is hosting the IAU South West Asian (SWA) Regional Office of Astronomy for Development (ROAD). It is a county of ancient astronomy and is also rich in modern astronomical facilities and infrastructures, hence may successfully serve as a regional center for various activities. Byurakan Astrophysical Observatory (BAO) has 2.6m and 1m Schmidt, as well as a number of smaller telescopes that are an observational basis for joint projects and collaborations. Armenian Virtual Observatory (ArVO) is hosting astronomical databases, such as the Digitized First Byurakan Survey (DFBS) and may also serve as a basis for development of VO structures in this region. Recently we have conducted a number of new activities; a meeting on ``Relation of Astronomy to other Sciences, Culture and Society" (RASCS) was organized by BAO and Armenian Astronomical Society (ArAS) in Oct 2014 in Byurakan. Activities related to Archaeoastronomy and Astronomy in Culture (AAC) were initiated as well. Discussions on future Armenian-Iranian collaboration in astronomy were carried out, including an Armenian-Iranian Astronomical Workshop held in Oct 2015 in Byurakan. Similar workshops have been carried out between BAO and Abastumani Astronomical Observatory (AbAO, Georgia) since 1974.
Effects of elevated line sources on turbulent mixing in channel flow
NASA Astrophysics Data System (ADS)
Nguyen, Quoc; Papavassiliou, Dimitrios
2016-11-01
Fluids mixing in turbulent flows has been studied extensively, due to the importance of this phenomena in nature and engineering. Convection effects along with motion of three-dimensional coherent structures in turbulent flow disperse a substance more efficiently than molecular diffusion does on its own. We present here, however, a study that explores the conditions under which turbulent mixing does not happen, when different substances are released into the flow field from different vertical locations. The study uses a method which combines Direct Numerical Simulation (DNS) with Lagrangian Scalar Tracking (LST) to simulate a turbulent channel flow and track the motion of passive scalars with different Schmidt numbers (Sc). The particles are released from several instantaneous line sources, ranging from the wall to the center region of the channel. The combined effects of mean velocity difference, molecular diffusion and near-wall coherent structures lead to the observation of different concentrations of particles downstream from the source. We then explore in details the conditions under which particles mixing would not happen. Results from numerical simulation at friction Reynolds number of 300 and 600 will be discussed and for Sc ranging from 0.1 to 2,400.
Probability density function of a puff dispersing from the wall of a turbulent channel
NASA Astrophysics Data System (ADS)
Nguyen, Quoc; Papavassiliou, Dimitrios
2015-11-01
Study of dispersion of passive contaminants in turbulence has proved to be helpful in understanding fundamental heat and mass transfer phenomena. Many simulation and experimental works have been carried out to locate and track motions of scalar markers in a flow. One method is to combine Direct Numerical Simulation (DNS) and Lagrangian Scalar Tracking (LST) to record locations of markers. While this has proved to be useful, high computational cost remains a concern. In this study, we develop a model that could reproduce results obtained by DNS and LST for turbulent flow. Puffs of markers with different Schmidt numbers were released into a flow field at a frictional Reynolds number of 150. The point of release was at the channel wall, so that both diffusion and convection contribute to the puff dispersion pattern, defining different stages of dispersion. Based on outputs from DNS and LST, we seek the most suitable and feasible probability density function (PDF) that represents distribution of markers in the flow field. The PDF would play a significant role in predicting heat and mass transfer in wall turbulence, and would prove to be helpful where DNS and LST are not always available.
Seymour-Smith, Sarah
2013-01-01
Researchers have observed gender differences in the frequency of emotion language used in cancer forums, with men more likely to seek medical information and women more likely to seek social and emotional support (Blank, Schmidt, Vangsness, Monteiro, & Santagata, 2010; Seale, Ziebland, & Charteris-Black, 2006). The aim of this article was to investigate Internet support groups to examine the support mechanisms that men employed when deciding whether or not to have a testicular implant. The four longest threads about prostheses were taken from four separate testicular cancer online support forums (totaling a number of 129 posts). A discursive approach (Edwards & Potter, 2001) was employed in order to consider what support mechanisms were employed by men. Findings illustrate that men employed a number of discursive strategies in "doing" support, including assessments, attending to issues of accountability, humor, providing alternative information, constructing decisions as personal choices, reconstituting normality, and sanctioning "emotional" talk. The psychological benefits of online homosocial support are discussed, and it is suggested that clinicians recommend Internet support groups to men with testicular cancer in order to start the psychological healing process. PsycINFO Database Record (c) 2013 APA, all rights reserved.
NASA Astrophysics Data System (ADS)
Sambath, P.; Pullepu, Bapuji; Hussain, T.; Ali Shehzad, Sabir
2018-03-01
The consequence of thermal radiation in laminar natural convective hydromagnetic flow of viscous incompressible fluid past a vertical cone with mass transfer under the influence of chemical reaction with heat source/sink is presented here. The surface of the cone is focused to a variable wall temperature (VWT) and wall concentration (VWC). The fluid considered here is a gray absorbing and emitting, but non-scattering medium. The boundary layer dimensionless equations governing the flow are solved by an implicit finite-difference scheme of Crank-Nicolson which has speedy convergence and stable. This method converts the dimensionless equations into a system of tri-diagonal equations and which are then solved by using well known Thomas algorithm. Numerical solutions are obtained for momentum, temperature, concentration, local and average shear stress, heat and mass transfer rates for various values of parameters Pr, Sc, λ, Δ, Rd are established with graphical representations. We observed that the liquid velocity decreased for higher values of Prandtl and Schmidt numbers. The temperature is boost up for decreasing values of Schimdt and Prandtl numbers. The enhancement in radiative parameter gives more heat to liquid due to which temperature is enhanced significantly.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sogin, H.H.; Goldstein, R.J.
1960-02-01
Experiments were performed on mass transfer by forced convection from naphthalene strips on a flat plate to an air stream at ordinary temperature and pressure. Turbulence was induced in the boundary layer by means of a wire strip. In all cases there was a hydrodynamic starting length upstream of the strips. The ratio of this inert length to the total length was varied from about 0.80 to 0.96. The flow was practically incompressible with Reynolds number, based on the total length, varying from 175,000 to 486,000. The Schmidt number was 2.5. The experimental results fell in proximity to the Sebanmore » step function factor when they were reduced after the massmomentum analysis of Deissler and Loeffler for a surface of uniform vapor pressure. When Karman's formulation of the mass- momentum analogy was assumed, the data fell between the values predicted by the Seban and by the Rubesin expression for the step function factor. The results were well correlated by the Colburn analogy in conjunction with the Rubesin step function factor. (auth)« less
NASA Technical Reports Server (NTRS)
Schmidt, Anja; Thordarson, Thorvaldur; Oman, Luke D.; Robock, Alan; Self, Stephen
2014-01-01
Here we respond to the comments by Cole-Dai et al. [2014] on our article Schmidt et al. [2012]. Specifically, in response to section 2 of their reply, we argued in Schmidt et al. [2012] that based on previously published estimates of the volatile release height during the 1783-1784 C.E. Laki eruption, the lack of a sulfur massindependent fractionation (MIF) anomaly is expected. In other words, no previous study on Laki ever argued that this eruption emitted SO2 into altitudes >13-15 km. In section 2.3, Cole-Dai et al. [2014] argue that the nonzero ?33S value of their Laki sample 1 may be explained by a short-lived explosive phase at Laki during which volatiles reached the stratosphere. In Schmidt et al. [2012] in section 2, we argued in agreement with Cole-Dai et al. [2014] (section 3.1) that for a MIF anomaly to be preserved, the Laki volatiles would have had to be emitted in >20 km altitude. Our main point is that eruption column heights >20 km are unlikely based on the historical accounts and plume-rise modeling for the Laki eruption [Stothers et al., 1986; Woods, 1993; Thordarson and Self, 2003]. In Schmidt et al. [2012], we argued that to deduce a short-lived climatic impact of the Laki eruption based on the lack of a MIF anomaly and the length of the sulfate deposition in Greenland ice cores may be misleading because the climatic impact will outlast the radiative forcing of the Laki aerosol cloud. Cole-Dai et al. [2014] acknowledge the latter in their reply in section 4.2. We agreewith Cole-Dai et al. [2014] in that themagnitude and length of the climatic impact during the winter of 1783-1784 depends on the altitude of the volatile release during the eruption (sections 2.3 and 4.2). However, even if we assumed that during Laki all sulfur dioxide (SO2) would have been released in the troposphere, then the aerosol cloud would still be present in the upper troposphere during March 1784, as is evident from independent model simulations of this "tropospheric-only" scenario [Stevenson et al., 2003]. We acknowledge that there is uncertainty on the volatile release height for Laki; however, it is worth considering that those climate model simulations that used an injection altitude between 9 km and 13 km for the Laki SO2 [Highwood and Stevenson, 2003; Oman et al., 2006a, 2006b; Schmidt et al., 2012] best match the observed temperature changes during summer of 1783 [Angell and Korshover, 1985; Brázdil et al., 2010; Briffa et al., 1998; D'Arrigo and Jacoby, 1999; Jacoby et al., 1999; Kington, 1988; Manley, 1974; Parker et al., 1992; Thordarson and Self, 2003]. Based on these model simulations, a climatic impact during the winter of 1783-1784, albeit weaker than during the climactic phases of Laki, is expected (and our argument here does not exclude the role of natural variability in contributing to the cold winter of 1783-1784 as discussed in Schmidt et al. [2012]). Therefore, we continue to argue that for high-latitude eruptions such as Laki, the applicability of sulfur isotopic measurements to interpret the climatic relevance has yet to be demonstrated. Itmay transpire that the interpretation of MIF signals for the climate-relevance of an eruption is valid and unambiguous only for short-lived explosive eruptions in the tropics. In terms of the processes producing a MIF anomaly (section 3.3 in Cole-Dai et al. [2014]), the works by Hattori et al. [2013] and Ono et al. [2013] suggest that there are remaining issues not discussed by Cole-Dai et al. [2014], for instance, self-shielding of SO2 due to high column densities typical for eruptions of Pinatubo-scale and greater, and the preservation of the MIF signature in general.
NASA Astrophysics Data System (ADS)
Burkart, F.; Schmidt, R.; Raginel, V.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.
2015-08-01
In a previous paper [Schmidt et al., Phys. Plasmas 21, 080701 (2014)], we presented the first results on beam-matter interaction experiments that were carried out at the High Radiation Materials test facility at CERN. In these experiments, extended cylindrical targets of solid copper were irradiated with beam of 440 GeV protons delivered by the Super Proton Synchrotron (SPS). The beam comprised of a large number of high intensity proton bunches, each bunch having a length of 0.5 ns with a 50 ns gap between two neighboring bunches, while the length of this entire bunch train was about 7 μs. These experiments established the existence of the hydrodynamic tunneling phenomenon the first time. Detailed numerical simulations of these experiments were also carried out which were reported in detail in another paper [Tahir et al., Phys. Rev. E 90, 063112 (2014)]. Excellent agreement was found between the experimental measurements and the simulation results that validate our previous simulations done using the Large Hadron Collider (LHC) beam of 7 TeV protons [Tahir et al., Phys. Rev. Spec. Top.--Accel. Beams 15, 051003 (2012)]. According to these simulations, the range of the full LHC proton beam and the hadronic shower can be increased by more than an order of magnitude due to the hydrodynamic tunneling, compared to that of a single proton. This effect is of considerable importance for the design of machine protection system for hadron accelerators such as SPS, LHC, and Future Circular Collider. Recently, using metal cutting technology, the targets used in these experiments have been dissected into finer pieces for visual and microscopic inspection in order to establish the precise penetration depth of the protons and the corresponding hadronic shower. This, we believe will be helpful in studying the very important phenomenon of hydrodynamic tunneling in a more quantitative manner. The details of this experimental work together with a comparison with the numerical simulations are presented in this paper.
The Flux of Large Meteoroids Observed with Lunar Impact Monitoring
NASA Technical Reports Server (NTRS)
Cooke, W. J.; Suggs, R. M.; Moser, D. E.; Suggs, R. J.
2014-01-01
The flux of large meteoroids is not well determined due to relatively low number statistics, due mainly to the lack of collecting area available to meteor camera systems (10(2)-10(5) km2). Larger collecting areas are needed to provide reasonable statistics for flux calculations. The Moon, with millions of square kilometers of lunar surface, can be used as a detector for observing the population of large meteoroids in the tens of grams to kilogram mass range. This is accomplished by observing the flash of light produced when a meteoroid impacts the lunar surface, converting a portion of its kinetic energy to visible light detectable from Earth. A routine monitoring program at NASA's Marshall Space Flight Center has recorded over 300 impact flashes since early 2006. The program utilizes multiple 0.35 m (14 inch) Schmidt-Cassegrain telescopes, outfitted with video cameras using the 1/2 inch Sony EXview HAD CCDTM chip, to perform simultaneous observations of the earthshine hemisphere of the Moon when the lunar phase is between 0.1 and 0.5. This optical arrangement permits monitoring of approximately 3.8x10(6) km2 of lunar surface. A selection of 126 flashes recorded in 266.88 hours of photometric skies was analyzed, creating the largest and most homogeneous dataset of lunar impact flashes to date. Standard CCD photometric techniques outlined in [1] were applied to the video to determine the luminous energy, kinetic energy, and mass for each impactor, considering a range of luminous efficiencies. The flux to a limiting energy of 2.5x10(-6) kT TNT or 1.05×10(7) J is 1.03×10(-7) km(-2) hr(-1) and the flux to a limiting mass of 30 g is 6.14×10(-10) m(-2) yr(-1). Comparisons made with measurements and models of the meteoroid population indicate that the flux of objects in this size range is slightly lower (but within the error bars) than the power law distribution determined for the near Earth object population by [2].
Using pan-sharpened high resolution satellite data to improve impervious surfaces estimation
NASA Astrophysics Data System (ADS)
Xu, Ru; Zhang, Hongsheng; Wang, Ting; Lin, Hui
2017-05-01
Impervious surface is an important environmental and socio-economic indicator for numerous urban studies. While a large number of researches have been conducted to estimate the area and distribution of impervious surface from satellite data, the accuracy for impervious surface estimation (ISE) is insufficient due to high diversity of urban land cover types. This study evaluated the use of panchromatic (PAN) data in very high resolution satellite image for improving the accuracy of ISE by various pan-sharpening approaches, with a further comprehensive analysis of its scale effects. Three benchmark pan-sharpening approaches, Gram-Schmidt (GS), PANSHARP and principal component analysis (PCA) were applied to WorldView-2 in three spots of Hong Kong. The on-screen digitization were carried out based on Google Map and the results were viewed as referenced impervious surfaces. The referenced impervious surfaces and the ISE results were then re-scaled to various spatial resolutions to obtain the percentage of impervious surfaces. The correlation coefficient (CC) and root mean square error (RMSE) were adopted as the quantitative indicator to assess the accuracy. The accuracy differences between three research areas were further illustrated by the average local variance (ALV) which was used for landscape pattern analysis. The experimental results suggested that 1) three research regions have various landscape patterns; 2) ISE accuracy extracted from pan-sharpened data was better than ISE from original multispectral (MS) data; and 3) this improvement has a noticeable scale effects with various resolutions. The improvement was reduced slightly as the resolution became coarser.
Which Competencies Are Most Important for Creative Expression?
ERIC Educational Resources Information Center
Epstein, Robert; Phan, Victoria
2012-01-01
In a follow-up to a previously published study (Epstein, Schmidt, & Warfel, 2008), an ethnically-diverse sample of 13,578 people in 47 countries (mainly the United States and Canada) took an online test that measures 4 trainable competencies that have been shown to enhance creative expression in individuals. The new study confirmed that the…
ERIC Educational Resources Information Center
Lam, Chak Fu; DeRue, D. Scott; Karam, Elizabeth P.; Hollenbeck, John R.
2011-01-01
Previous research on feedback frequency suggests that more frequent feedback improves learning and task performance (Salmoni, Schmidt, & Walter, 1984). Drawing from resource allocation theory (Kanfer & Ackerman, 1989), we challenge the "more is better" assumption and propose that frequent feedback can overwhelm an individual's cognitive resource…
ERIC Educational Resources Information Center
Reynolds, Jennifer L.
2010-01-01
Cross country investigations have repeatedly demonstrated the disappointing math performance of students in the United States (Beatty, 1997; Ferrini-Mundy & Schmidt, 2005). The National Council of Teachers of Mathematics (2000) listed failure to rapidly recall basic facts as a common problem associated with disabilities in mathematics and…
Design-Construct Method Saves Time and Money in New School Building
ERIC Educational Resources Information Center
Modern Schools, 1972
1972-01-01
Describes the Lottie M. Schmidt Elementary School in New Baltimore, Michigan, completed in 154 days. Designed to a price rather than priced to a design, the school was built at considerable savings over modular approaches -- and the modest price also covered furniture, electric heating/cooling, carpeting, full masonry construction, concrete slab…
DECam SAM 0.9-m CCD Goodman SOI Optical Spectrographs CHIRON COSMOS Goodman Filters Telescopes Blanco 4 magnitudes, astrometric, and spectral properties Filters Filter Overview Filter list (all filters up to and including 4x4-inch, sorted by wavelength) Filters - 3 & 4 inch (for SOAR, Schmidt, 0.9-m imaging
Governance for a New Era: A Blueprint for Higher Education Trustees
ERIC Educational Resources Information Center
Schmidt, Benno C.
2014-01-01
"Governance for a New Era: A Blueprint for Higher Education Governance," is the product of a summit facilitated by ACTA [American Council of Trustees and Alumni] and chaired by Benno Schmidt, City University of New York Board chairman. Signatories to the statement, a diverse group of 22 distinguished national leaders, include college…
ERIC Educational Resources Information Center
Delta Pi Epsilon Society, Little Rock, AR.
Selected titles of refereed research papers contained in this volume include the following: "Analysis of Computer Use by Four-Year University Faculty Members" (Duff et al.); "Analysis of Undergraduate Coursework Completed by Prospective Business Teachers" (Schmidt et al.); "Business Educators' Perceptions Regarding the Integration of Business…
Media and Attention, Cognition, and School Achievement
ERIC Educational Resources Information Center
Schmidt, Marie Evans; Vandewater, Elizabeth A.
2008-01-01
Marie Evans Schmidt and Elizabeth Vandewater review research on links between various types of electronic media and the cognitive skills of school-aged children and adolescents. One central finding of studies to date, they say, is that the content delivered by electronic media is far more influential than the media themselves. Most studies, they…
ERIC Educational Resources Information Center
Bain, Ryan M.; Pulliam, Christopher J.; Yan, Xin; Moore, Kassandra F.; Mu¨ller, Thomas; Cooks, R. Graham
2014-01-01
Undergraduate laboratories generally teach an understanding of chemical reactivity using bulk or semimicroscale experiments with product isolation and subsequent chemical and spectroscopic analysis. In this study students were exposed to mass spectrometry as a means of chemical synthesis as well as analysis. The ionization method used, paper…
Raymond C. Shearer
2008-01-01
The larches - Larix P. Mill. - of the world are usually grouped into 10 species that are widely distributed over much of the mountainous, cooler regions of the Northern Hemisphere (Hora 1981; Krussmann 1985; Ostenfeld and Larsen 1930; Rehder 1940; Schmidt 1995). Some species dominate at the northern limits of boreal forests and others occur above subalpine forests (...
Optical Photometry of the Nova Outburst TCP J04432130+4721280 (V392 Per)
NASA Astrophysics Data System (ADS)
Konyves-Toth, R.; Csak, B.; Pal, A.; Vinko, J.
2018-05-01
We obtained new photometric observations of TCP J04432130+4721280 (V392 Per, ATel #11588, #11590), R.A = 04:43:21.38, Dec = +47:21:25.9, on 2018-04-30.80 UT. The data were taken with the 60/90 cm Schmidt telescope at Konkoly Observatory, Piszkesteto, Hungary.
Numerical Simulation of Adaptive Control Applicaton to Unstable Solid Rocket Motors
2001-06-01
la Technologie des Lanceurs "Vi- Sciences Meeting & Exhibit, Reno, Jan. 15-18. bration des Lanceurs , Toulouse", 1999. AIAA Paper 96-0759, 1996. 7-8...Schmidt. Some recent de- in the presence of pipeline acoustic resonance. velopments in numerical methods for transonic J. Fluids and Structures ., 5:207
Gender Affects Semantic Competition: The Effect of Gender in a Non-Gender-Marking Language
ERIC Educational Resources Information Center
Fukumura, Kumiko; Hyönä, Jukka; Scholfield, Merete
2013-01-01
English speakers tend to produce fewer pronouns when a referential competitor has the same gender as the referent than otherwise. Traditionally, this gender congruence effect has been explained in terms of ambiguity avoidance (e.g., Arnold, Eisenband, Brown-Schmidt, & Trueswell, 2000; Fukumura, Van Gompel, & Pickering, 2010). However, an…
Integrated research in constitutive modelling at elevated temperatures, part 2
NASA Technical Reports Server (NTRS)
Haisler, W. E.; Allen, D. H.
1986-01-01
Four current viscoplastic models are compared experimentally with Inconel 718 at 1100 F. A series of tests were performed to create a sufficient data base from which to evaluate material constants. The models used include Bodner's anisotropic model; Krieg, Swearengen, and Rhode's model; Schmidt and Miller's model; and Walker's exponential model.
Fireball multi object spectrograph: as-built optic performances
NASA Astrophysics Data System (ADS)
Grange, R.; Milliard, B.; Lemaitre, G.; Quiret, S.; Pascal, S.; Origné, A.; Hamden, E.; Schiminovich, D.
2016-07-01
Fireball (Faint Intergalactic Redshifted Emission Balloon) is a NASA/CNES balloon-borne experiment to study the faint diffuse circumgalactic medium from the line emissions in the ultraviolet (200 nm) above 37 km flight altitude. Fireball relies on a Multi Object Spectrograph (MOS) that takes full advantage of the new high QE, low noise 13 μm pixels UV EMCCD. The MOS is fed by a 1 meter diameter parabola with an extended field (1000 arcmin2) using a highly aspherized two mirror corrector. All the optical train is working at F/2.5 to maintain a high signal to noise ratio. The spectrograph (R 2200 and 1.5 arcsec FWHM) is based on two identical Schmidt systems acting as collimator and camera sharing a 2400 g/mm aspherized reflective Schmidt grating. This grating is manufactured from active optics methods by double replication technique of a metal deformable matrix whose active clear aperture is built-in to a rigid elliptical contour. The payload and gondola are presently under integration at LAM. We will present the alignment procedure and the as-built optic performances of the Fireball instrument.
Processing of Digital Plates1.2m of Baldone Observatory Schmidt Telescope
NASA Astrophysics Data System (ADS)
Eglitis, Ilgmars; Andruk, Vitaly
2017-04-01
The aim of this research is to evaluate accuracy of Plate Processing Method and to perform a detailed study of the Epson Expression 10000XL scanner, which was used to digitize plates from the database collection of the 1.2 m Schmidt Telescope installed in the Baldone Observatory. Special software developed in LINUX/MIDAS/ROMAFOT environment was used for processing the scans. Results of the digitized files with grey gradations of 8- and 16-bits were compared; an estimation of the accuracy of the developed method for rectangular coordinates determination and photometry was made. Errors in the instrumental system are ±0.026 pixels and ±0.024m for coordinates and stellar magnitudes respectively. To evaluate the repeatability of the scanner's astrometric and photometric errors, six consecutive scans of one plate were processed with a spatial separation of 1200 dpi. The following error estimations are obtained for stars brighter than U< 13.5m: σxy = ±0.021 to 0.027 pixels and σm = ±0.014m to 0.016m for rectangular coordinates and instrumental stellar magnitudes respectively.
Ultrasound accelerated Claisen Schmidt condensation: A green route to chalcones
NASA Astrophysics Data System (ADS)
Calvino, V.; Picallo, M.; López-Peinado, A. J.; Martín-Aranda, R. M.; Durán-Valle, C. J.
2006-06-01
Chalcones have been synthesized under sonochemical irradiation by Claisen-Schmidt condensation between benzaldehyde and acetophenone. Two basic activated carbons (Na and Cs-Norit) have been used as catalysts. The effect of the ultrasound activation has been studied. A substantial enhancing effect in the yield was observed when the carbon catalyst was activated under ultrasonic waves. This "green" method (combination of alkaline-doped carbon catalyst and ultrasound waves) has been applied to the synthesis of several chalcones with antibacterial properties achieving, in all cases, excellent activities and selectivities. A comparative study under non-sonic activation has showed that the yields are lower in silent conditions, indicating that the sonication exerts a positive effect on the activity of the catalyst. Cs-doped carbon is presented as the optimum catalyst, giving excellent activity for this type of condensation. Cs-Norit carbon catalyst can compete with the traditional NaOH/EtOH when the reaction is carried out under ultrasounds. The role of solvent in this reaction was studied with ethanol. High conversion was obtained in absence of solvent. The carbons were characterized by thermal analysis, nitrogen adsorption and X-ray photoelectron spectroscopy.
NASA Technical Reports Server (NTRS)
Campbell-Brown, M. D.; Braid, D.
2011-01-01
The flux of meteoroids, or number of meteoroids per unit area per unit time, is critical for calibrating models of meteoroid stream formation and for estimating the hazard to spacecraft from shower and sporadic meteors. Although observations of meteors in the millimetre to centimetre size range are common, flux measurements (particularly for sporadic meteors, which make up the majority of meteoroid flux) are less so. It is necessary to know the collecting area and collection time for a given set of observations, and to correct for observing biases and the sensitivity of the system. Previous measurements of sporadic fluxes are summarized in Figure 1; the values are given as a total number of meteoroids striking the earth in one year to a given limiting mass. The Gr n et al. (1985) flux model is included in the figure for reference. Fluxes for sporadic meteoroids impacting the Earth have been calculated for objects in the centimeter size range using Super-Schmidt observations (Hawkins & Upton, 1958); this study used about 300 meteors, and used only the physical area of overlap of the cameras at 90 km to calculate the flux, corrected for angular speed of meteors, since a large angular speed reduces the maximum brightness of the meteor on the film, and radiant elevation, which takes into account the geometric reduction in flux when the meteors are not perpendicular to the horizontal. They bring up corrections for both partial trails (which tends to increase the collecting area) and incomplete overlap at heights other than 90 km (which tends to decrease it) as effects that will affect the flux, but estimated that the two effects cancelled one another. Halliday et al. (1984) calculated the flux of meteorite-dropping fireballs with fragment masses greater than 50 g, over the physical area of sky accessible to the MORP fireball cameras, counting only observations in clear weather. In the micron size range, LDEF measurements of small craters on spacecraft have been used to estimate the flux (Love & Brownlee, 1993); here the physical area of the detector is well known, but the masses depend strongly on the unknown velocity distribution. In the same size range, Thomas & Netherway (1989) used the narrow-beam radar at Jindalee to calculate the flux of sporadics. In between these very large and very small sizes, a number of video and photographic observations were reduced by Ceplecha (2001). These fluxes were calculated (details are given in Ceplecha, 1988) taking the Halliday et al. (1984) MORP fireball fluxes, slightly corrected in mass, as a calibration, and adjusting the flux of small cameras to overlap with the number/mass relation from that work.
NASA Astrophysics Data System (ADS)
Miller, A.; Zykov, V.
2016-02-01
Schmidt Ocean Institute's vision is that the world's ocean be understood through technological advancement, intelligent observation, and open sharing of information. As such, making data collected aboard R/V Falkor available to the general public is a key pillar of the organization and a major strategic focus. Schmidt Ocean Institute supports open sharing of information about the ocean to stimulate the growth of its applications and user community, and amplify further exploration, discovery, and deeper understanding of our environment. These efforts are supported through partnerships with data management experts in the oceanographic community to enable standards-compliant sharing of scientific information and data collected during research cruises. To properly fulfill the commitment, proponents' data management plans are evaluated as part of the proposal process when applying for ship time. We request a thorough data management plan be submitted and expert reviewers evaluate the proposal's plan as part of the review process. Once a project is successfully selected, the chief scientist signs an agreement stating delivery dates for post-cruise data deliverables in a timely manner, R/V Falkor underway and meterological data is shared via public repositories, and links and reports are posted on the cruise webpage. This allows many more creative minds and thinkers to analyze, process, and study the data collected in the world ocean rather than privileging one scientist with the proprietary information, driving international and national scientific progress. This presentation will include the Institute's mission, vision, and strategy for sharing data, based on our Founders' passions, the process for evaluating proposed data management plans, and our partnering efforts to make data publically available in fulfillment of our commitment. Recent achievements and successes in data sharing, as well as future plans to improve our efforts will also be discussed.
NASA Astrophysics Data System (ADS)
Nývlt, Daniel; Braucher, Régis; Engel, Zbyněk; Mlčoch, Bedřich
2014-09-01
The Northern Prince Gustav Ice Stream located in Prince Gustav Channel, drained the northeastern portion of the Antarctic Peninsula Ice Sheet during the last glacial maximum. Here we present a chronology of its retreat based on in situ produced cosmogenic 10Be from erratic boulders at Cape Lachman, northern James Ross Island. Schmidt hammer testing was adopted to assess the weathering state of erratic boulders in order to better interpret excess cosmogenic 10Be from cumulative periods of pre-exposure or earlier release from the glacier. The weighted mean exposure age of five boulders based on Schmidt hammer data is 12.9 ± 1.2 ka representing the beginning of the deglaciation of lower-lying areas (< 60 m a.s.l.) of the northern James Ross Island, when Northern Prince Gustav Ice Stream split from the remaining James Ross Island ice cover. This age represents the minimum age of the transition from grounded ice stream to floating ice shelf in the middle continental shelf areas of the northern Prince Gustav Channel. The remaining ice cover located at higher elevations of northern James Ross Island retreated during the early Holocene due to gradual decay of terrestrial ice and increase of equilibrium line altitude. Schmidt hammer R-values are inversely correlated with 10Be exposure ages and could be used as a proxy for exposure history of individual granite boulders in this region and favour the hypothesis of earlier release of boulders with excessive 10Be concentrations from glacier directly at this site. These data provide evidences for an earlier deglaciation of northern James Ross Island when compared with other recently presented cosmogenic nuclide based deglaciation chronologies, but this timing coincides with rapid increase of atmospheric temperature in this marginal part of Antarctica.
NASA Astrophysics Data System (ADS)
Wong, O. Ivy; Vega, O.; Sánchez-Argüelles, D.; Narayanan, G.; Wall, W. F.; Zwaan, M. A.; Rosa González, D.; Zeballos, M.; Bekki, K.; Mayya, Y. D.; Montaña, A.; Chung, A.
2017-04-01
We report an early science discovery of the 12CO(1-0) emission line in the collisional ring galaxy VII Zw466, using the Redshift Search Receiver instrument on the Large Millimeter Telescope Alfonso Serrano. The apparent molecular-to-atomic gas ratio either places the interstellar medium (ISM) of VII Zw466 in the H I-dominated regime or implies a large quantity of CO-dark molecular gas, given its high star formation rate. The molecular gas densities and star formation rate densities of VII Zw466 are consistent with the standard Kennicutt-Schmidt star formation law even though we find this galaxy to be H2-deficient. The choice of CO-to-H2 conversion factors cannot explain the apparent H2 deficiency in its entirety. Hence, we find that the collisional ring galaxy, VII Zw466, is either largely deficient in both H2 and H I or contains a large mass of CO-dark gas. A low molecular gas fraction could be due to the enhancement of feedback processes from previous episodes of star formation as a result of the star-forming ISM being confined to the ring. We conclude that collisional ring galaxy formation is an extreme form of galaxy interaction that triggers a strong galactic-wide burst of star formation that may provide immediate negative feedback towards subsequent episodes of star formation - resulting in a short-lived star formation history or, at least, the appearance of a molecular gas deficit.
VizieR Online Data Catalog: Periods of 4-10 Myr old T Tauri members of Orion OB1 (Karim+, 2016)
NASA Astrophysics Data System (ADS)
Karim, M. T.; Stassun, K. G.; Briceno, C.; Vivas, A. K.; Raetz, S.; Mateu, C.; Downes, J. J.; Calvet, N.; Hernandez, J.; Neuhauser, R.; Mugrauer, M.; Takahashi, H.; Tachihara, K.; Chini, R.; Cruz-Dias, G. A.; Aarnio, A.; James, D. J.; Hackstein, M.
2017-02-01
The Astronomia Variability Survey of Orion (CVSO) was carried out at the Llano del Hato National Astronomical Observatory in Venezuela, with the QUEST CCD mosaic camera (8000*8000pixels) on the 1m (clear aperture) Schmidt telescope, with a plate scale of 1.02''/pixel and field of view of 5.4 deg2. This V-, RC-, and IC-band multi-epoch survey, covering ~180deg2 of the Orion OB1 association, spans a time baseline of 12yr, from 1998 December to 2011 February. The 25 Ori cluster was observed by the 0.6/0.9m Schmidt-type telescope at Jena Observatory (Germany), the two 5.9'' telescopes at Observatorio Cerro Armazones (OCA, Chile), and the 1.5m reflector at the Gunma Astronomical Observatory in Japan, over four observing campaigns during the years 2010-2013. The Jena Schmidt-type telescope was equipped with the optical Schmidt Telescope Camera (STK), with an e2v 42-10 2048*2048 detector, yielding a plate scale of 1.55''/pixel and a field of view of 53'*53', thus encompassing most of the cluster. The Jena 50s exposures, all taken through the R filter, were centered on 25 Ori. A total of 8506 individual exposures were obtained in 108 nights. The Gunma 1.5m reflector observations were carried out by obtaining 60s integrations in R with the Gunma Low-resolution Spectrograph and Imager (GLOWS), which has an e2v CCD55-30 1250*1152 pixel detector with a 0.6''/pixel scale, covering a field of view of 12.5'*11.5'. Observations were obtained during four nights in year 2010. The Observatorio Cerro Armazones observations were done in the R band using the RoBoTT (Robotic Bochum TWin Telescope), which consists of twin Takahashi 150mm aperture apochromatic astrographs, each equipped with an Apogee U16M camera with a KAF-16803 4096*4096 pixel CCD, providing a 2.7°*2.7° field of view with 2.37''/pixel scale. The 60s exposures were centered on 25 Ori, spanning an area much larger than the cluster. OCA data were obtained during all YETI seasons. During the nights of 2006 January 8-15, we used the 0.9m telescope with the 8000*8000 pixel MOSAIC imager at the Kitt Peak National Observatory (KPNO), Arizona, USA, to obtain IC-band time-series observations of several regions in the Orion OB1 association, including the 25 Ori cluster in the OB1a subassociation, and fields in the OB1b subassociation, under NOAO program 2005B-0529. (1 data file).
Four things we don't know about scalar transfer from plant canopies
NASA Astrophysics Data System (ADS)
Finnigan, J. J.
2009-04-01
In terrestrial plant canopies, turbulent exchange of water through evapotranspiration is intimately bound up with exchange of other scalars, heat and carbon dioxide in particular. Turbulent transport is rarely the process limiting exchange of these scalars between the biosphere and the atmosphere. However, in measurement programs like FLUXNET or when we parameterise surface exchange at the canopy scale in climate or weather models we must understand the mechanism of turbulent exchange in detail. In this talk we survey four current obstacles to extending our understanding of canopy turbulence from the idealised case of homogeneous flow in neutral stratification to complex flows in stable and unstable conditions. 1. Canopy eddy structure and the hydrodynamic instability Recent analysis of canopy LES and wind tunnel simulations has revealed the ‘two hairpin' structure of a characteristic canopy eddy. This structure explains a large body of results from a wide range of canopies and redefines the Roughness Sub Layer (RSL) as an asymptotic layer similar to the logarithmic and outer layers of the Planetary Boundary Layer. However, the nature of the non-linear ‘mixing-layer' instability process that gives canopy/RSL eddies their coherence and enhanced transport efficiency (as compared to eddies in the logarithmic layer above) is poorly understood so we do not know how resilient this instability and the eddies that depend upon it are to large scale flow perturbations or to changes in stability. 2. Turbulent Schmidt and Prandtl Numbers The scalar RSL can be defined as the layer across which the turbulent Schmidt (Sc) and Prandtl (Pr) numbers in neutral stratification change from their canopy top values of ~0.5, typical of mixing layers, to their logarithmic layer values of ~1.0, typical of boundary layers. The value of Sc or Pr is a critical parameter when adjusting Monin-Obukhov similarity theory (MOST) for the proximity of the canopy. The need for such adjustments has been recognized for several decades but they are still often ignored with serious consequences for prognostic models. However, at the present time we have only weak experimental evidence for the values of Sc and Pr in neutral conditions. More importantly, our poor understanding of the processes that set Sc and Pr and control their variation with diabatic stability is a barrier to generalizing MOST for use above tall canopies. 3. Diabatic stability and canopy flows As radiative cooling proceeds after sundown, turbulence within dense canopies can collapse suddenly leading to decoupling of the canopy layer from the boundary layer above. Theory suggests that this process should occur because of the different transport mechanisms of scalars and momentum at leaf level. So far no definitive experimental results are available to confirm or refute this theory or to set bounds on its applicability. This has important implications for transport and canopy microclimate. In particular we need to know how the controlling time scales of this process depend upon canopy density and radiative transfer. 4. Gravity currents Deep coherent gravity currents are often observed on long hill slopes covered with tall canopies. The process of turbulent collapse after sundown mentioned in (3) above produces a deep stable layer which is decoupled from the boundary layer above and must come into a new dynamic balance involving the hydrostatic and hydrodynamic pressure gradients and canopy drag. Scale analysis suggests that the strength of such currents depends upon hill length rather than hill slope while wind tunnel experiments reveal that they can penetrate onto flat ground far upwind of the hills on which they originate. Many field sites where flow is well behaved during the day can, therefore, be affected by such gravity flows at night. The parameters controlling the unsteady dynamics of this situation are not known but are of critical importance to measurements of water and other trace gas exchange over the diurnal cycle. The four topics chosen move from the fundamentals of canopy eddy structure to the impact at large scale of microscale processes. Each requires us to consider simultaneously processes from the leaf to the whole canopy scale and each will require effort from the whole community if serious progress is to be made.
Effective surface and boundary conditions for heterogeneous surfaces with mixed boundary conditions
NASA Astrophysics Data System (ADS)
Guo, Jianwei; Veran-Tissoires, Stéphanie; Quintard, Michel
2016-01-01
To deal with multi-scale problems involving transport from a heterogeneous and rough surface characterized by a mixed boundary condition, an effective surface theory is developed, which replaces the original surface by a homogeneous and smooth surface with specific boundary conditions. A typical example corresponds to a laminar flow over a soluble salt medium which contains insoluble material. To develop the concept of effective surface, a multi-domain decomposition approach is applied. In this framework, velocity and concentration at micro-scale are estimated with an asymptotic expansion of deviation terms with respect to macro-scale velocity and concentration fields. Closure problems for the deviations are obtained and used to define the effective surface position and the related boundary conditions. The evolution of some effective properties and the impact of surface geometry, Péclet, Schmidt and Damköhler numbers are investigated. Finally, comparisons are made between the numerical results obtained with the effective models and those from direct numerical simulations with the original rough surface, for two kinds of configurations.
NASA Technical Reports Server (NTRS)
Wegner, Gary A.
1988-01-01
Research under NASA Grant NAG5-287 has carried out a number of projects in conjunction with the International Ultraviolet Explorer (IUE) satellite. These include: (1) studies of the UV spectra of DA white dwarfs which show quasi-molecular bands of H2 and H2(+); (2) the peculiar star HR6560; (3) the UV spectra of two magnetic white dwarfs that also show the quasi-molecular features; (4) investigations of the UV spectra of subluminous stars, primarily identified from visual wavelength spectroscopy in the Kiso survey of UV excess stars, some of which show interesting metal lines in their UV spectra; and (5) completion of studies of UV spectra of DB stars. The main result of this research has been to further knowledge of the structure and compositions of subluminous stars which helps cast light on their formation and evolution.
NASA Astrophysics Data System (ADS)
Khan, Noor Saeed; Gul, Taza; Khan, Muhammad Altaf; Bonyah, Ebenezer; Islam, Saeed
Mixed convection in gravity-driven non-Newtonian nanofluid films (Casson and Williamson) flow containing both nanoparticles and gyrotactic microorganisms along a convectively heated vertical surface is investigated. The actively controlled nanofluid model boundary conditions are used to explore the liquid films flow. The study exhibits an analytical approach for the non-Newtonian thin film nanofluids bioconvection based on physical mechanisms responsible for the nanoparticles and the base fluid, such as Brownian motion and thermophoresis. Both the fluids have almost the same behaviors for the effects of all the pertinent parameters except the effect of Schmidt number on the microorganism density function where the effect is opposite. Ordinary differential equations together with the boundary conditions are obtained through similarity variables from the governing equations of the problem, which are solved by HAM (Homotopy Analysis Method). The solution is expressed through graphs and illustrated which show the influences of all the parameters. The study is relevant to novel microbial fuel cell technologies combining the nanofluid with bioconvection phenomena.
Microscale Obstacle Resolving Air Quality Model Evaluation with the Michelstadt Case
Rakai, Anikó; Kristóf, Gergely
2013-01-01
Modelling pollutant dispersion in cities is challenging for air quality models as the urban obstacles have an important effect on the flow field and thus the dispersion. Computational Fluid Dynamics (CFD) models with an additional scalar dispersion transport equation are a possible way to resolve the flowfield in the urban canopy and model dispersion taking into consideration the effect of the buildings explicitly. These models need detailed evaluation with the method of verification and validation to gain confidence in their reliability and use them as a regulatory purpose tool in complex urban geometries. This paper shows the performance of an open source general purpose CFD code, OpenFOAM for a complex urban geometry, Michelstadt, which has both flow field and dispersion measurement data. Continuous release dispersion results are discussed to show the strengths and weaknesses of the modelling approach, focusing on the value of the turbulent Schmidt number, which was found to give best statistical metric results with a value of 0.7. PMID:24027450
Microscale obstacle resolving air quality model evaluation with the Michelstadt case.
Rakai, Anikó; Kristóf, Gergely
2013-01-01
Modelling pollutant dispersion in cities is challenging for air quality models as the urban obstacles have an important effect on the flow field and thus the dispersion. Computational Fluid Dynamics (CFD) models with an additional scalar dispersion transport equation are a possible way to resolve the flowfield in the urban canopy and model dispersion taking into consideration the effect of the buildings explicitly. These models need detailed evaluation with the method of verification and validation to gain confidence in their reliability and use them as a regulatory purpose tool in complex urban geometries. This paper shows the performance of an open source general purpose CFD code, OpenFOAM for a complex urban geometry, Michelstadt, which has both flow field and dispersion measurement data. Continuous release dispersion results are discussed to show the strengths and weaknesses of the modelling approach, focusing on the value of the turbulent Schmidt number, which was found to give best statistical metric results with a value of 0.7.
NASA Technical Reports Server (NTRS)
Justice, Erin; Newcomer, Michelle
2010-01-01
The western half of the United States is made up of a number of diverse ecosystems ranging from arid desert to coastal wetlands and rugged forests. Every summer for the past 7 years students ranging from high school to graduate level gather at NASA Ames Research Center (ARC) as part of the DEVELOP Internship Program. Under the guidance of Jay Skiles [Ames Research Center (ARC) - Ames DEVELOP Manager] and Cindy Schmidt [ARC/San Jose State University Ames DEVELOP Coordinator] they work as a team on projects exploring topics including: invasive species, carbon flux, wetland restoration, air quality monitoring, storm visualizations, and forest fires. The study areas for these projects have been in Washington, Utah, Oregon, Nevada, Hawaii, Alaska and California. Interns combine data from NASA and partner satellites with models and in situ measurements to complete prototype projects demonstrating how NASA data and resources can help communities tackle their Earth Science related problems.
Rectangular rotation of spherical harmonic expansion of arbitrary high degree and order
NASA Astrophysics Data System (ADS)
Fukushima, Toshio
2017-08-01
In order to move the polar singularity of arbitrary spherical harmonic expansion to a point on the equator, we rotate the expansion around the y-axis by 90° such that the x-axis becomes a new pole. The expansion coefficients are transformed by multiplying a special value of Wigner D-matrix and a normalization factor. The transformation matrix is unchanged whether the coefficients are 4 π fully normalized or Schmidt quasi-normalized. The matrix is recursively computed by the so-called X-number formulation (Fukushima in J Geodesy 86: 271-285, 2012a). As an example, we obtained 2190× 2190 coefficients of the rectangular rotated spherical harmonic expansion of EGM2008. A proper combination of the original and the rotated expansions will be useful in (i) integrating the polar orbits of artificial satellites precisely and (ii) synthesizing/analyzing the gravitational/geomagnetic potentials and their derivatives accurately in the high latitude regions including the arctic and antarctic area.
NASA Astrophysics Data System (ADS)
Soltanian-Zadeh, Hamid; Windham, Joe P.
1992-04-01
Maximizing the minimum absolute contrast-to-noise ratios (CNRs) between a desired feature and multiple interfering processes, by linear combination of images in a magnetic resonance imaging (MRI) scene sequence, is attractive for MRI analysis and interpretation. A general formulation of the problem is presented, along with a novel solution utilizing the simple and numerically stable method of Gram-Schmidt orthogonalization. We derive explicit solutions for the case of two interfering features first, then for three interfering features, and, finally, using a typical example, for an arbitrary number of interfering feature. For the case of two interfering features, we also provide simplified analytical expressions for the signal-to-noise ratios (SNRs) and CNRs of the filtered images. The technique is demonstrated through its applications to simulated and acquired MRI scene sequences of a human brain with a cerebral infarction. For these applications, a 50 to 100% improvement for the smallest absolute CNR is obtained.
VizieR Online Data Catalog: Rotation periods of asteroids using iPTF (Chang+, 2016)
NASA Astrophysics Data System (ADS)
Chang, C.-K.; Lin, H.-W.; Ip, W.-H.; Prince, T. A.; Kulkarni, S. R.; Levitan, D.; Laher, R.; Surace, J.
2017-01-01
To explore the transient and variable sky synoptically, the PTF/iPTF employs the Palomar 48-inch Oschin Schmidt Telescope to create a field of view of ~7.26deg2 and a pixel scale of 1.01". The available filters include the Mould-R band, with which most exposures were taken, Gunn-g', and two different Hα-bands. The exposure time is fixed at 60 seconds, which can reach a median limiting magnitude of R~21mag at the 5σ level. In order to look for large super-fast rotators, we conducted five asteroid rotation-period surveys during 2014 October 29-31 and November 10-13, and 2015 January 18-19, February 20-21 and 25-26. Each survey continuously scanned six consecutive PTF fields over the ecliptic plane in the R-band, with a cadence of 10min. We ended up with a total sky coverage of ~188deg2. (3 data files).
Catadioptric Optics for laser Doppler velocimeter applications
NASA Technical Reports Server (NTRS)
Dunagan, Stephen E.
1989-01-01
In the design of a laser velocimeter system, attention must be given to the performance of the optical elements in their two principal tasks: focusing laser radiation into the probe volume, and collecting the scattered light. For large aperture applications, custom lens design and fabrication costs, long optical path requirements, and chromatic aberration (for two color operation) can be problematic. The adaptation of low cost Schmidt-Cassegrain astronomical telescopes to perform these laser beam manipulation and scattered light collection tasks is examined. A generic telescope design is analyzed using ray tracing and Gaussian beam propagation theory, and a simple modification procedure for converting from infinite to near unity conjugate ratio operation with image quality near the diffraction limit was identified. Modification requirements and performance are predicted for a range of geometries. Finally, a 200-mm-aperture telescope was modified for f/10 operation; performance data for this modified optic for both laser beam focusing and scattered light collection tasks agree well with predictions.
NASA Astrophysics Data System (ADS)
Shvelidze, T. D.; Malyuto, V. D.
Quantitative spectral classification of F, G and K stars with the 70-cm telescope of the Ambastumani Astrophysical Observatory in areas of the main meridional section of the Galaxy, and for which proper motion data are available, has been performed. Fundamental parameters have been obtained for 333 stars in four areas. Space densities of stars of different spectral types, the stellar luminosity function and the relationships between the kinematics and metallicity of stars have been studied. The results have confirmed and completed the conclusions made on the basis of some previous spectroscopic and photometric surveys. Many plates have been obtained for other important directions in the sky: the Kapteyn areas, the Galactic anticentre and the main meridional section of the Galaxy. The data can be treated with the same quantitative method applied here. This method may also be applied to other available and future spectroscopic data of similar resolution, notably that obtained with large format CCD detectors on Schmidt-type telescopes.
2012-03-14
only two snake species on the Guam, the other of which is a burrowing blind snake Ramphotyphlops braminus (possibly introduced as well), and none of...descriptions of three new species. Systematic Parasitology 1:127-140. Roberts, L. S. and J. J. Janovy. 2005. Gerald D. Schmidt and Larry S. Roberts
CQI 101: A First Reader for Higher Education. AAHE's Continuous Quality Improvement Project.
ERIC Educational Resources Information Center
American Association for Higher Education, Washington, DC.
This collection of papers introduces the core ideas of Continuous Quality Improvement (CQI), as Total Quality Management is known in the field of higher education, and underscores its usefulness and relevance for higher education. Papers have the following titles and authors: "The Roots of the TQM Movement" (Warren Schmidt and Jerome Finnigan);…
Correcting for Indirect Range Restriction in Meta-Analysis: Testing a New Meta-Analytic Procedure
ERIC Educational Resources Information Center
Le, Huy; Schmidt, Frank L.
2006-01-01
Using computer simulation, the authors assessed the accuracy of J. E. Hunter, F. L. Schmidt, and H. Le's (2006) procedure for correcting for indirect range restriction, the most common type of range restriction, in comparison with the conventional practice of applying the Thorndike Case II correction for direct range restriction. Hunter et…
78 FR 77782 - Qualification of Drivers; Exemption Applications; Vision
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-24
... (OH) Marvin L. Motes (FL) Charles W. Mullenix (GA) Richard W. O'Neill (WA) Harold L. Pearsall (PA.... Ramirez (TX) Jason W. Rupp (PA) Eric W. Schmidt (MO) Jerry W. Stanfill (AR) Wilfred E. Sweatt (NH) Roger L...) Anthony D. Buck (TX) Shaun E. Burnett (IA) Kevin W. Cannon (TX) James J. Doan (PA) Shennan E. Dorsey (GA...