Anderson localization for radial tree-like random quantum graphs

NASA Astrophysics Data System (ADS)

Hislop, Peter D.; Post, Olaf

We prove that certain random models associated with radial, tree-like, rooted quantum graphs exhibit Anderson localization at all energies. The two main examples are the random length model (RLM) and the random Kirchhoff model (RKM). In the RLM, the lengths of each generation of edges form a family of independent, identically distributed random variables (iid). For the RKM, the iid random variables are associated with each generation of vertices and moderate the current flow through the vertex. We consider extensions to various families of decorated graphs and prove stability of localization with respect to decoration. In particular, we prove Anderson localization for the random necklace model.

Correspondence: Reply to ‘Phantom phonon localization in relaxors’

DOE PAGES

Manley, Michael E.; Abernathy, Douglas L.; Budai, John D.

2017-12-05

The Correspondence by Gehring et al. mistakes Anderson phonon localization for the concept of an atomic-scale local mode. An atomic-scale local mode refers to a single atom vibrating on its own within a crystal. Such a local mode will have an almost flat intensity profile, but this is not the same as phonon localization. Anderson localization is a wave interference effect in a disordered system that results in waves becoming spatially localized. The length scale of the localized waves is set by the wavelength, which is approximately 2 nm in this case. This larger length scale in real space meansmore » narrower intensity profiles in reciprocal space. Here, we conclude that the claims in the Correspondence by Gehring et al. are incorrect because they mistakenly assume that the length scale for Anderson localization is atomic, and because the experimental observations rule out multiple scattering as the origin.« less

Correspondence: Reply to ‘Phantom phonon localization in relaxors’

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

Manley, Michael E.; Abernathy, Douglas L.; Budai, John D.

The Correspondence by Gehring et al. mistakes Anderson phonon localization for the concept of an atomic-scale local mode. An atomic-scale local mode refers to a single atom vibrating on its own within a crystal. Such a local mode will have an almost flat intensity profile, but this is not the same as phonon localization. Anderson localization is a wave interference effect in a disordered system that results in waves becoming spatially localized. The length scale of the localized waves is set by the wavelength, which is approximately 2 nm in this case. This larger length scale in real space meansmore » narrower intensity profiles in reciprocal space. Here, we conclude that the claims in the Correspondence by Gehring et al. are incorrect because they mistakenly assume that the length scale for Anderson localization is atomic, and because the experimental observations rule out multiple scattering as the origin.« less

Anderson localization in Nb/Al superconducting bilayers

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

Greco, M.; Lacquaniti, V.; Maggi, S.

2000-01-01

The authors have measured the temperature dependence of resistivity in relatively thick Nb/Al bilayers fabricated at room temperature, observing the decrease of {rho} for increasing T typical of Anderson localization in disordered systems. The authors report the experimental conditions which determine this behavior and compare it to theoretical models for localization in 3D systems.

Anderson localization in sigma models

NASA Astrophysics Data System (ADS)

Bruckmann, Falk; Wellnhofer, Jacob

2018-03-01

In QCD above the chiral restoration temperature there exists an Anderson transition in the fermion spectrum from localized to delocalized modes. We investigate whether the same holds for nonlinear sigma models which share properties like dynamical mass generation and asymptotic freedom with QCD. In particular we study the spectra of fermions coupled to (quenched) CP(N-1) configurations at high temperatures. We compare results in two and three space-time dimensions: in two dimensions the Anderson transition is absent, since all fermion modes are localized, while in three dimensions it is present. Our measurements include a more recent observable characterizing level spacings: the distribution of ratios of consecutive level spacings.

Mott-Hubbard transition and Anderson localization: A generalized dynamical mean-field theory approach

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

Kuchinskii, E. Z.; Nekrasov, I. A.; Sadovskii, M. V.

The DOS, the dynamic (optical) conductivity, and the phase diagram of a strongly correlated and strongly disordered paramagnetic Anderson-Hubbard model are analyzed within the generalized dynamical mean field theory (DMFT + {sigma} approximation). Strong correlations are taken into account by the DMFT, and disorder is taken into account via an appropriate generalization of the self-consistent theory of localization. The DMFT effective single-impurity problem is solved by a numerical renormalization group (NRG); we consider the three-dimensional system with a semielliptic DOS. The correlated metal, Mott insulator, and correlated Anderson insulator phases are identified via the evolution of the DOS and dynamicmore » conductivity, demonstrating both the Mott-Hubbard and Anderson metal-insulator transition and allowing the construction of the complete zero-temperature phase diagram of the Anderson-Hubbard model. Rather unusual is the possibility of a disorder-induced Mott insulator-to-metal transition.« less

Anderson localization of graphene by helium ion irradiation

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

Naitou, Y., E-mail: yu-naitou@aist.go.jp; Ogawa, S.

Irradiation of a single-layer graphene (SLG) with accelerated helium ions (He{sup +}) controllably generates defect distributions, which create a charge carrier scattering source within the SLG. We report direct experimental observation of metal-insulator transition in SLG on SiO{sub 2}/Si substrates induced by Anderson localization. This transition was investigated using scanning capacitance microscopy by monitoring the He{sup +} dose conditions on the SLG. The experimental data show that a defect density of more than ∼1.2% induced Anderson localization. We also investigated the localization length by determining patterned placement of the defects and estimated the length to be several dozen nanometers. Thesemore » findings provide valuable insight for patterning and designing graphene-based nanostructures using helium ion microscopy.« less

Encoding the structure of many-body localization with matrix product operators

NASA Astrophysics Data System (ADS)

Pekker, David; Clark, Bryan K.

2015-03-01

Anderson insulators are non-interacting disordered systems which have localized single particle eigenstates. The interacting analogue of Anderson insulators are the Many-Body Localized (MBL) phases. The natural language for representing the spectrum of the Anderson insulator is that of product states over the single-particle modes. We show that product states over Matrix Product Operators of small bond dimension is the corresponding natural language for describing the MBL phases. In this language all of the many-body eigenstates are encode by Matrix Product States (i.e. DMRG wave function) consisting of only two sets of low bond-dimension matrices per site: the Gi matrix corresponding to the local ground state on site i and the Ei matrix corresponding to the local excited state. All 2 n eigenstates can be generated from all possible combinations of these matrices.

Observation of migrating transverse Anderson localizations of light in nonlocal media.

PubMed

Leonetti, Marco; Karbasi, Salman; Mafi, Arash; Conti, Claudio

2014-05-16

We report the experimental observation of the interaction and attraction of many localized modes in a two-dimensional system realized by a disordered optical fiber supporting transverse Anderson localization. We show that a nonlocal optically nonlinear response of thermal origin alters the localization length by an amount determined by the optical power and also induces an action at a distance between the localized modes and their spatial migration. Evidence of a collective and strongly interacting regime is given.

Quantum jumps on Anderson attractors

NASA Astrophysics Data System (ADS)

Yusipov, I. I.; Laptyeva, T. V.; Ivanchenko, M. V.

2018-01-01

In a closed single-particle quantum system, spatial disorder induces Anderson localization of eigenstates and halts wave propagation. The phenomenon is vulnerable to interaction with environment and decoherence that is believed to restore normal diffusion. We demonstrate that for a class of experimentally feasible non-Hermitian dissipators, which admit signatures of localization in asymptotic states, quantum particle opts between diffusive and ballistic regimes, depending on the phase parameter of dissipators, with sticking about localization centers. In a diffusive regime, statistics of quantum jumps is non-Poissonian and has a power-law interval, a footprint of intermittent locking in Anderson modes. Ballistic propagation reflects dispersion of an ordered lattice and introduces the second timescale for jumps, resulting in non-nonmonotonous probability distribution. Hermitian dephasing dissipation makes localization features vanish, and Poissonian jump statistics along with normal diffusion are recovered.

Encoding the structure of many-body localization with matrix product operators

NASA Astrophysics Data System (ADS)

Pekker, David; Clark, Bryan K.

2017-01-01

Anderson insulators are noninteracting disordered systems which have localized single-particle eigenstates. The interacting analog of Anderson insulators are the many-body localized (MBL) phases. The spectrum of the many-body eigenstates of an Anderson insulator is efficiently represented as a set of product states over the single-particle modes. We show that product states over matrix product operators of small bond dimension is the corresponding efficient description of the spectrum of an MBL insulator. In this language all of the many-body eigenstates are encoded by matrix product states (i.e., density matrix renormalization group wave functions) consisting of only two sets of low bond dimension matrices per site: the Gi matrices corresponding to the local ground state on site i and the Ei matrices corresponding to the local excited state. All 2n eigenstates can be generated from all possible combinations of these sets of matrices.

Finite-size effects in Anderson localization of one-dimensional Bose-Einstein condensates

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

Cestari, J. C. C.; Foerster, A.; Gusmao, M. A.

We investigate the disorder-induced localization transition in Bose-Einstein condensates for the Anderson and Aubry-Andre models in the noninteracting limit using exact diagonalization. We show that, in addition to the standard superfluid fraction, other tools such as the entanglement and fidelity can provide clear signatures of the transition. Interestingly, the fidelity exhibits good sensitivity even for small lattices. Effects of the system size on these quantities are analyzed in detail, including the determination of a finite-size-scaling law for the critical disorder strength in the case of the Anderson model.

LOFT. Construction view of tunnel during 1957 to compare with ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOFT. Construction view of tunnel during 1957 to compare with HAER photo ID-33-E-358 above. Tunnel sections were pre-cast, then joined together. Photographer described this as :Personnel and service tunnel running east-west in test building of the FET." Date: December 19, 1957. Photographer: Jack L. Anderson. INEEL negative no. 57-6206 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Substitutional impurity in single-layer graphene: The Koster–Slater and Anderson models

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

Davydov, S. Yu., E-mail: sergei-davydov@mail.ru

The Koster–Slater and Anderson models are used to consider substitutional impurities in free-standing single-layer graphene. The density of states of graphene is described using a model (the M model). For the nitrogen and boron impurities, the occupation numbers and the parameter η which defines the fraction of delocalized electrons of the impurity are determined. In this case, experimental data are used for both determination of the model parameters and comparison with the results of theoretical estimations. The general features of the Koster–Slater and Anderson models and the differences between the two models are discussed. Specifically, it is shown that themore » band contributions to the occupation numbers of a nitrogen atom in both models are comparable, whereas the local contributions are substantially different: the local contributions are decisive in the Koster–Slater model and negligible in the Anderson model. The asymptotic behavior of the wave functions of a defect is considered in the Koster–Slater model, and the electron states of impurity dimers are considered in the Anderson model.« less

Local Improvement Results for Anderson Acceleration with Inaccurate Function Evaluations

DOE PAGES

Toth, Alex; Ellis, J. Austin; Evans, Tom; ...

2017-10-26

Here, we analyze the convergence of Anderson acceleration when the fixed point map is corrupted with errors. We also consider uniformly bounded errors and stochastic errors with infinite tails. We prove local improvement results which describe the performance of the iteration up to the point where the accuracy of the function evaluation causes the iteration to stagnate. We illustrate the results with examples from neutronics.

Local Improvement Results for Anderson Acceleration with Inaccurate Function Evaluations

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

Toth, Alex; Ellis, J. Austin; Evans, Tom

Here, we analyze the convergence of Anderson acceleration when the fixed point map is corrupted with errors. We also consider uniformly bounded errors and stochastic errors with infinite tails. We prove local improvement results which describe the performance of the iteration up to the point where the accuracy of the function evaluation causes the iteration to stagnate. We illustrate the results with examples from neutronics.

Anderson localization of shear waves observed by magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Papazoglou, S.; Klatt, D.; Braun, J.; Sack, I.

2010-07-01

In this letter we present for the first time an experimental investigation of shear wave localization using motion-sensitive magnetic resonance imaging (MRI). Shear wave localization was studied in gel phantoms containing arrays of randomly positioned parallel glass rods. The phantoms were exposed to continuous harmonic vibrations in a frequency range from 25 to 175 Hz, yielding wavelengths on the order of the elastic mean free path, i.e. the Ioffe-Regel criterion of Anderson localization was satisfied. The experimental setup was further chosen such that purely shear horizontal waves were induced to avoid effects due to mode conversion and pressure waves. Analysis of the distribution of shear wave intensity in experiments and simulations revealed a significant deviation from Rayleigh statistics indicating that shear wave energy is localized. This observation is further supported by experiments on weakly scattering samples exhibiting Rayleigh statistics and an analysis of the multifractality of wave functions. Our results suggest that motion-sensitive MRI is a promising tool for studying Anderson localization of time-harmonic shear waves, which are increasingly used in dynamic elastography.

Theoretical study of the dependence of single impurity Anderson model on various parameters within distributional exact diagonalization method

NASA Astrophysics Data System (ADS)

Syaina, L. P.; Majidi, M. A.

2018-04-01

Single impurity Anderson model describes a system consisting of non-interacting conduction electrons coupled with a localized orbital having strongly interacting electrons at a particular site. This model has been proven successful to explain the phenomenon of metal-insulator transition through Anderson localization. Despite the well-understood behaviors of the model, little has been explored theoretically on how the model properties gradually evolve as functions of hybridization parameter, interaction energy, impurity concentration, and temperature. Here, we propose to do a theoretical study on those aspects of a single impurity Anderson model using the distributional exact diagonalization method. We solve the model Hamiltonian by randomly generating sampling distribution of some conducting electron energy levels with various number of occupying electrons. The resulting eigenvalues and eigenstates are then used to define the local single-particle Green function for each sampled electron energy distribution using Lehmann representation. Later, we extract the corresponding self-energy of each distribution, then average over all the distributions and construct the local Green function of the system to calculate the density of states. We repeat this procedure for various values of those controllable parameters, and discuss our results in connection with the criteria of the occurrence of metal-insulator transition in this system.

Anderson localization and Mott insulator phase in the time domain

PubMed Central

Sacha, Krzysztof

2015-01-01

Particles in space periodic potentials constitute standard models for investigation of crystalline phenomena in solid state physics. Time periodicity of periodically driven systems is a close analogue of space periodicity of solid state crystals. There is an intriguing question if solid state phenomena can be observed in the time domain. Here we show that wave-packets localized on resonant classical trajectories of periodically driven systems are ideal elements to realize Anderson localization or Mott insulator phase in the time domain. Uniform superpositions of the wave-packets form stationary states of a periodically driven particle. However, an additional perturbation that fluctuates in time results in disorder in time and Anderson localization effects emerge. Switching to many-particle systems we observe that depending on how strong particle interactions are, stationary states can be Bose-Einstein condensates or single Fock states where definite numbers of particles occupy the periodically evolving wave-packets. Our study shows that non-trivial crystal-like phenomena can be observed in the time domain. PMID:26074169

Time-dependent reflection at the localization transition

NASA Astrophysics Data System (ADS)

Skipetrov, Sergey E.; Sinha, Aritra

2018-03-01

A short quasimonochromatic wave packet incident on a semi-infinite disordered medium gives rise to a reflected wave. The intensity of the latter decays as a power law, 1 /tα , in the long-time limit. Using the one-dimensional Aubry-André model, we show that in the vicinity of the critical point of Anderson localization transition, the decay slows down, and the power-law exponent α becomes smaller than both α =2 found in the Anderson localization regime and α =3 /2 expected for a one-dimensional random walk of classical particles.

Finite-time scaling at the Anderson transition for vibrations in solids

NASA Astrophysics Data System (ADS)

Beltukov, Y. M.; Skipetrov, S. E.

2017-11-01

A model in which a three-dimensional elastic medium is represented by a network of identical masses connected by springs of random strengths and allowed to vibrate only along a selected axis of the reference frame exhibits an Anderson localization transition. To study this transition, we assume that the dynamical matrix of the network is given by a product of a sparse random matrix with real, independent, Gaussian-distributed nonzero entries and its transpose. A finite-time scaling analysis of the system's response to an initial excitation allows us to estimate the critical parameters of the localization transition. The critical exponent is found to be ν =1.57 ±0.02 , in agreement with previous studies of the Anderson transition belonging to the three-dimensional orthogonal universality class.

Effect of Hilbert space truncation on Anderson localization

NASA Astrophysics Data System (ADS)

Krishna, Akshay; Bhatt, R. N.

2018-05-01

The 1D Anderson model possesses a completely localized spectrum of eigenstates for all values of the disorder. We consider the effect of projecting the Hamiltonian to a truncated Hilbert space, destroying time-reversal symmetry. We analyze the ensuing eigenstates using different measures such as inverse participation ratio and sample-averaged moments of the position operator. In addition, we examine amplitude fluctuations in detail to detect the possibility of multifractal behavior (characteristic of mobility edges) that may arise as a result of the truncation procedure.

Anderson localization of electrons in single crystals: LixFe7Se8

PubMed Central

Ying, Tianping; Gu, Yueqiang; Chen, Xiao; Wang, Xinbo; Jin, Shifeng; Zhao, Linlin; Zhang, Wei; Chen, Xiaolong

2016-01-01

Anderson (disorder-induced) localization, proposed more than half a century ago, has inspired numerous efforts to explore the absence of wave diffusions in disordered media. However, the proposed disorder-induced metal-insulator transition (MIT), associated with the nonpropagative electron waves, has hardly been observed in three-dimensional (3D) crystalline materials, let alone single crystals. We report the observation of an MIT in centimeter-size single crystals of LixFe7Se8 induced by lattice disorder. Both specific heat and infrared reflectance measurements reveal the presence of considerable electronic states in the vicinity of the Fermi level when the MIT occurs, suggesting that the transition is not due to Coulomb repulsion mechanism. The 3D variable range hopping regime evidenced by electrical transport measurements at low temperatures indicates the localized nature of the electronic states on the Fermi level. Quantitative analyses of carrier concentration, carrier mobility, and simulated density of states (DOS) fully support that LixFe7Se8 is an Anderson insulator. On the basis of these results, we provide a unified DOS picture to explain all the experimental results, and a schematic diagram for finding other potential Anderson insulators. This material will thus serve as a rich playground for both theoretical and experimental investigations on MITs and disorder-induced phenomena. PMID:26989781

Anderson localization of partially incoherent light

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

Capeta, D.; Radic, J.; Buljan, H.

We study Anderson localization and propagation of partially spatially incoherent wavepackets in linear disordered potentials, motivated by the insight that interference phenomena resulting from multiple scattering are affected by the coherence of the waves. We find that localization is delayed by incoherence: the more incoherent the waves are, the longer they diffusively spread while propagating in the medium. However, if all the eigenmodes of the system are exponentially localized (as in one- and two-dimensional disordered systems), any partially incoherent wavepacket eventually exhibits localization with exponentially decaying tails, after sufficiently long propagation distances. Interestingly, we find that the asymptotic behavior ofmore » the incoherent beam is similar to that of a single instantaneous coherent realization of the beam.« less

Single-particle dynamics of the Anderson model: a local moment approach

NASA Astrophysics Data System (ADS)

Glossop, Matthew T.; Logan, David E.

2002-07-01

A non-perturbative local moment approach to single-particle dynamics of the general asymmetric Anderson impurity model is developed. The approach encompasses all energy scales and interaction strengths. It captures thereby strong coupling Kondo behaviour, including the resultant universal scaling behaviour of the single-particle spectrum; as well as the mixed valence and essentially perturbative empty orbital regimes. The underlying approach is physically transparent and innately simple, and as such is capable of practical extension to lattice-based models within the framework of dynamical mean-field theory.

Can 3D light localization be reached in ‘white paint’?

NASA Astrophysics Data System (ADS)

Sperling, T.; Schertel, L.; Ackermann, M.; Aubry, G. J.; Aegerter, C. M.; Maret, G.

2016-01-01

When waves scatter multiple times in 3D random media, a disorder driven phase transition from diffusion to localization may occur (Anderson 1958 Phys. Rev. 109 1492-505 Abrahams et al 1979 Phys. Rev. Lett. 42 673-6). In ‘The question of classical localization: a theory of white paint?’ Anderson suggested the possibility to observe light localization in TiO2 samples (Anderson 1985 Phil. Mag. B 52 505-9). We recently claimed the observation of localization effects measuring photon time of flight (ToF) distributions (Störzer et al 2006 Phys. Rev. Lett. 96 063904) and evaluating transmission profiles (TPs) (Sperling et al 2013 Nat. Photonics 7 48-52) in such TiO2 samples. Here we present a careful study of the long time tail of ToF distributions and the long time behavior of the TP width for very thin samples and different turbidities that questions the localization interpretation. We further show new data that allow an alternative consistent explanation of these previous data by a fluorescence process. An adapted diffusion model including an appropriate exponential fluorescence decay accounts for the shape of the ToF distributions and the TP width. These observations question whether the strong localization regime can be reached with visible light scattering in polydisperse TiO2 samples, since the disorder parameter can hardly be increased any further in such a ‘white paint’ material.

Coherent wave transmission in quasi-one-dimensional systems with Lévy disorder

NASA Astrophysics Data System (ADS)

Amanatidis, Ilias; Kleftogiannis, Ioannis; Falceto, Fernando; Gopar, Víctor A.

2017-12-01

We study the random fluctuations of the transmission in disordered quasi-one-dimensional systems such as disordered waveguides and/or quantum wires whose random configurations of disorder are characterized by density distributions with a long tail known as Lévy distributions. The presence of Lévy disorder leads to large fluctuations of the transmission and anomalous localization, in relation to the standard exponential localization (Anderson localization). We calculate the complete distribution of the transmission fluctuations for a different number of transmission channels in the presence and absence of time-reversal symmetry. Significant differences in the transmission statistics between disordered systems with Anderson and anomalous localizations are revealed. The theoretical predictions are independently confirmed by tight-binding numerical simulations.

Conductance fluctuation of edge-disordered graphene nanoribbons: Crossover from diffusive transport to Anderson localization

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

Takashima, Kengo; Yamamoto, Takahiro, E-mail: takahiro@rs.tus.ac.jp; Department of Liberal Arts

Conductance fluctuation of edge-disordered graphene nanoribbons (ED-GNRs) is examined using the non-equilibrium Green's function technique combined with the extended Hückel approximation. The mean free path λ and the localization length ξ of the ED-GNRs are determined to classify the quantum transport regimes. In the diffusive regime where the length L{sub c} of the ED-GNRs is much longer than λ and much shorter than ξ, the conductance histogram is given by a Gaussian distribution function with universal conductance fluctuation. In the localization regime where L{sub c}≫ξ, the histogram is no longer the universal Gaussian distribution but a lognormal distribution that characterizesmore » Anderson localization.« less

Chaos-assisted tunneling in the presence of Anderson localization.

PubMed

Doggen, Elmer V H; Georgeot, Bertrand; Lemarié, Gabriel

2017-10-01

Tunneling between two classically disconnected regular regions can be strongly affected by the presence of a chaotic sea in between. This phenomenon, known as chaos-assisted tunneling, gives rise to large fluctuations of the tunneling rate. Here we study chaos-assisted tunneling in the presence of Anderson localization effects in the chaotic sea. Our results show that the standard tunneling rate distribution is strongly modified by localization, going from the Cauchy distribution in the ergodic regime to a log-normal distribution in the strongly localized case, for both a deterministic and a disordered model. We develop a single-parameter scaling description which accurately describes the numerical data. Several possible experimental implementations using cold atoms, photonic lattices, or microwave billiards are discussed.

Entanglement Area Law in Disordered Free Fermion Anderson Model in One, Two, and Three Dimensions

DOE PAGES

Pouranvari, Mohammad; Zhang, Yuhui; Yang, Kun

2015-01-01

We calculate numerically the entanglement entropy of free fermion ground states in one-, two-, and three-dimensional Anderson models and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger than the mean free path. This result holds in the metallic phase of the three-dimensional Anderson model, where the mean free path is finite although the localization length is infinite. Relation between the present results and earlier ones on area law violation in special one-dimensional models that support metallic phases is discussed.

Entanglement Area Law in Disordered Free Fermion Anderson Model in One, Two, and Three Dimensions

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

Pouranvari, Mohammad; Zhang, Yuhui; Yang, Kun

We calculate numerically the entanglement entropy of free fermion ground states in one-, two-, and three-dimensional Anderson models and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger than the mean free path. This result holds in the metallic phase of the three-dimensional Anderson model, where the mean free path is finite although the localization length is infinite. Relation between the present results and earlier ones on area law violation in special one-dimensional models that support metallic phases is discussed.

Localization noise in deep subwavelength plasmonic devices

NASA Astrophysics Data System (ADS)

Ghoreyshi, Ali; Victora, R. H.

2018-05-01

The grain shape dependence of absorption has been investigated in metal-insulator thin films. We demonstrate that randomness in the size and shape of plasmonic particles can lead to Anderson localization of polarization modes in the deep subwavelength regime. These localized modes can contribute to significant variation in the local field. In the case of plasmonic nanodevices, the effects of the localized modes have been investigated by mapping an electrostatic Hamiltonian onto the Anderson Hamiltonian in the presence of a random vector potential. We show that local behavior of the optical beam can be understood in terms of the weighted local density of the localized modes of the depolarization field. Optical nanodevices that operate on a length scale with high variation in the density of states of localized modes will experience a previously unidentified localized noise. This localization noise contributes uncertainty to the output of plasmonic nanodevices and limits their scalability. In particular, the resulting impact on heat-assisted magnetic recording is discussed.

Integrals of motion for one-dimensional Anderson localized systems

DOE PAGES

Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.; ...

2016-03-02

Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. Weanswer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precisemore » sense, motivate our construction.Wenote that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order.Weshow that despite the infinite range hopping, all states but one are localized.Wealso study the conservation laws for the disorder free Aubry–Andre model, where the states are either localized or extended, depending on the strength of a coupling constant.Weformulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry–Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Lastly, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.« less

Integrals of motion for one-dimensional Anderson localized systems

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

Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.

Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. Weanswer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precisemore » sense, motivate our construction.Wenote that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order.Weshow that despite the infinite range hopping, all states but one are localized.Wealso study the conservation laws for the disorder free Aubry–Andre model, where the states are either localized or extended, depending on the strength of a coupling constant.Weformulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry–Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Lastly, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.« less

Integrals of motion for one-dimensional Anderson localized systems

NASA Astrophysics Data System (ADS)

Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.; Shastry, B. Sriram

2016-03-01

Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. We answer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precise sense, motivate our construction. We note that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order. We show that despite the infinite range hopping, all states but one are localized. We also study the conservation laws for the disorder free Aubry-Andre model, where the states are either localized or extended, depending on the strength of a coupling constant. We formulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry-Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Finally, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.

Anderson transition in a three-dimensional kicked rotor

NASA Astrophysics Data System (ADS)

Wang, Jiao; García-García, Antonio M.

2009-03-01

We investigate Anderson localization in a three-dimensional (3D) kicked rotor. By a finite-size scaling analysis we identify a mobility edge for a certain value of the kicking strength k=kc . For k>kc dynamical localization does not occur, all eigenstates are delocalized and the spectral correlations are well described by Wigner-Dyson statistics. This can be understood by mapping the kicked rotor problem onto a 3D Anderson model (AM) where a band of metallic states exists for sufficiently weak disorder. Around the critical region k≈kc we carry out a detailed study of the level statistics and quantum diffusion. In agreement with the predictions of the one parameter scaling theory (OPT) and with previous numerical simulations, the number variance is linear, level repulsion is still observed, and quantum diffusion is anomalous with ⟨p2⟩∝t2/3 . We note that in the 3D kicked rotor the dynamics is not random but deterministic. In order to estimate the differences between these two situations we have studied a 3D kicked rotor in which the kinetic term of the associated evolution matrix is random. A detailed numerical comparison shows that the differences between the two cases are relatively small. However in the deterministic case only a small set of irrational periods was used. A qualitative analysis of a much larger set suggests that deviations between the random and the deterministic kicked rotor can be important for certain choices of periods. Heuristically it is expected that localization effects will be weaker in a nonrandom potential since destructive interference will be less effective to arrest quantum diffusion. However we have found that certain choices of irrational periods enhance Anderson localization effects.

Dynamical Localization for Unitary Anderson Models

NASA Astrophysics Data System (ADS)

Hamza, Eman; Joye, Alain; Stolz, Günter

2009-11-01

This paper establishes dynamical localization properties of certain families of unitary random operators on the d-dimensional lattice in various regimes. These operators are generalizations of one-dimensional physical models of quantum transport and draw their name from the analogy with the discrete Anderson model of solid state physics. They consist in a product of a deterministic unitary operator and a random unitary operator. The deterministic operator has a band structure, is absolutely continuous and plays the role of the discrete Laplacian. The random operator is diagonal with elements given by i.i.d. random phases distributed according to some absolutely continuous measure and plays the role of the random potential. In dimension one, these operators belong to the family of CMV-matrices in the theory of orthogonal polynomials on the unit circle. We implement the method of Aizenman-Molchanov to prove exponential decay of the fractional moments of the Green function for the unitary Anderson model in the following three regimes: In any dimension, throughout the spectrum at large disorder and near the band edges at arbitrary disorder and, in dimension one, throughout the spectrum at arbitrary disorder. We also prove that exponential decay of fractional moments of the Green function implies dynamical localization, which in turn implies spectral localization. These results complete the analogy with the self-adjoint case where dynamical localization is known to be true in the same three regimes.

Entanglement complexity in quantum many-body dynamics, thermalization, and localization

NASA Astrophysics Data System (ADS)

Yang, Zhi-Cheng; Hamma, Alioscia; Giampaolo, Salvatore M.; Mucciolo, Eduardo R.; Chamon, Claudio

2017-07-01

Entanglement is usually quantified by von Neumann entropy, but its properties are much more complex than what can be expressed with a single number. We show that the three distinct dynamical phases known as thermalization, Anderson localization, and many-body localization are marked by different patterns of the spectrum of the reduced density matrix for a state evolved after a quantum quench. While the entanglement spectrum displays Poisson statistics for the case of Anderson localization, it displays universal Wigner-Dyson statistics for both the cases of many-body localization and thermalization, albeit the universal distribution is asymptotically reached within very different time scales in these two cases. We further show that the complexity of entanglement, revealed by the possibility of disentangling the state through a Metropolis-like algorithm, is signaled by whether the entanglement spectrum level spacing is Poisson or Wigner-Dyson distributed.

Detailed investigation of the impact of the fiber design parameters on the transverse Anderson localization of light in disordered optical fibers.

PubMed

Karbasi, Salman; Mirr, Craig R; Frazier, Ryan J; Yarandi, Parisa Gandomkar; Koch, Karl W; Mafi, Arash

2012-08-13

We recently reported the observation of transverse Anderson localization as the waveguiding mechanism in optical fibers with random transverse refractive index profiles [Opt. Lett. 37, 2304 (2012)]. Here, we explore the impact of the design parameters of the disordered fiber on the beam radius of the propagating transverse localized beam. We show that the optimum value of the fill-fraction of the disorder is 50% and a lower value results in a larger beam radius. We also explore the impact of the average size of the individual random features on the value of the localized beam radius and show how the boundary of the fiber can impact the observed localization radius. A larger refractive index contrast between the host medium and the disorder sites results in smaller value of the beam radius.

Classical Coset Hamiltonian for the Electronic Motion and its Application to Anderson Localization and Hammett Equation

NASA Astrophysics Data System (ADS)

Xing, Guan; Wu, Guo-Zhen

2001-02-01

A classical coset Hamiltonian is introduced for the system of one electron in multi-sites. By this Hamiltonian, the dynamical behaviour of the electronic motion can be readily simulated. The simulation reproduces the retardation of the electron density decay in a lattice with site energies randomly distributed - an analogy with Anderson localization. This algorithm is also applied to reproduce the Hammett equation which relates the reaction rate with the property of the substitutions in the organic chemical reactions. The advantages and shortcomings of this algorithm, as contrasted with traditional quantum methods such as the molecular orbital theory, are also discussed.

Element-resolved atomic structure imaging of rocksalt Ge{sub 2}Sb{sub 2}Te{sub 5} phase-change material

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

Zhang, Bin; Chen, Yongjin; Han, Xiaodong, E-mail: wzhang0@mail.xjtu.edu.cn, E-mail: ema@jhu.edu, E-mail: xdhan@bjut.edu.cn

Disorder-induced electron localization and metal-insulator transitions (MITs) have been a very active research field starting from the seminal paper by Anderson half a century ago. However, pure Anderson insulators are very difficult to identify due to ubiquitous electron-correlation effects. Recently, an MIT has been observed in electrical transport measurements on the crystalline state of phase-change GeSbTe compounds, which appears to be exclusively disorder driven. Subsequent density functional theory simulations have identified vacancy disorder to localize electrons at the Fermi level. Here, we report a direct atomic scale chemical identification experiment on the rocksalt structure obtained upon crystallization of amorphous Ge{submore » 2}Sb{sub 2}Te{sub 5}. Our results confirm the two-sublattice structure resolving the distribution of chemical species and demonstrate the existence of atomic disorder on the Ge/Sb/vacancy sublattice. Moreover, we identify a gradual vacancy ordering process upon further annealing. These findings not only provide a structural underpinning of the observed Anderson localization but also have implications for the development of novel multi-level data storage within the crystalline phases.« less

Interplay of Anderson localization and quench dynamics

NASA Astrophysics Data System (ADS)

Rahmani, Armin; Vishveshwara, Smitha

2018-06-01

In the context of an isolated three-dimensional noninteracting fermionic lattice system, we study the effects of a sudden quantum quench between a disorder-free situation and one in which disorder results in a mobility edge and associated Anderson localization. Salient post-quench features hinge upon the overlap between momentum states and post-quench eigenstates and whether these latter states are extended or localized. We find that the post-quench momentum distribution directly reflects these overlaps. For the local density, we show that disorder generically prevents the equilibration of quantum expectation values to a steady state and that the persistent fluctuations have a nonmonotonic dependence on the strength of disorder. We identify two distinct types of fluctuations, namely, temporal fluctuations describing the time-dependent fluctuations of the local density around its time average and sample-to-sample fluctuations characterizing the variations of these time averages from one realization of disorder to another. We demonstrate that both of these fluctuations vanish for extremely extended as well as extremely localized states, peaking at some intermediate value.

Anomaly in the band centre of the one-dimensional Anderson model

NASA Astrophysics Data System (ADS)

Kappus, M.; Wegner, F.

1981-03-01

We calculate the density of states and various characteristic lengths of the one-dimensional Anderson model in the limit of weak disorder. All these quantities show anomalous fluctuations near the band centre. This has already been observed for the density of states in a different model by Gorkov and Dorokhov, and is in close agreement with a Monte-Carlo calculation for the localization length by Czycholl, Kramer and Mac-Kinnon.

Anderson Localization in Quark-Gluon Plasma

NASA Astrophysics Data System (ADS)

Kovács, Tamás G.; Pittler, Ferenc

2010-11-01

At low temperature the low end of the QCD Dirac spectrum is well described by chiral random matrix theory. In contrast, at high temperature there is no similar statistical description of the spectrum. We show that at high temperature the lowest part of the spectrum consists of a band of statistically uncorrelated eigenvalues obeying essentially Poisson statistics and the corresponding eigenvectors are extremely localized. Going up in the spectrum the spectral density rapidly increases and the eigenvectors become more and more delocalized. At the same time the spectral statistics gradually crosses over to the bulk statistics expected from the corresponding random matrix ensemble. This phenomenon is reminiscent of Anderson localization in disordered conductors. Our findings are based on staggered Dirac spectra in quenched lattice simulations with the SU(2) gauge group.

Paleontological analysis of a lacustrine carbonaceous uranium deposit at the Anderson mine, Date Creek basin, west-central Arizona (U.S.A.)

USGS Publications Warehouse

Otton, J.K.; Bradbury, J.P.; Forester, R.M.; Hanley, J.H.

1990-01-01

The Tertiary sedimentary sequence of the Date Creek basin area of Arizona is composed principally of intertonguing alluvial-fan and lacustrine deposits. The lacustrine rocks contain large intermediate- to, locally, high-grade uranium deposits that form one of the largest uranium resources in the United States (an estimated 670,000 tons of U3O8 at an average grade of 0.023% is indicated by drilling to date). At the Anderson mine, about 50,000 tons of U3O8 occurs in lacustrine carbonaceous siltstones and mudstones (using a cutoff grade of 0.01%). The Anderson mine constitutes a new class of ore deposit, a lacustrine carbonaceous uranium deposit. Floral and faunal remains at the Anderson mine played a critical role in creating and documenting conditions necessary for uranium mineralization. Organic-rich, uraniferous rocks at the Anderson mine contain plant remains and ostracodes having remarkably detailed preservation of internal features because of infilling by opaline silica. This preservation suggests that the alkaline lake waters in the mine area contained high concentrations of dissolved silica and that silicification occurred rapidly, before compaction or cementation of the enclosing sediment. Uranium coprecipitated with the silica. Thinly laminated, dark-colored, siliceous beds contain centric diatoms preserved with carbonaceous material suggesting that lake waters at the mine were locally deep and anoxic. These alkaline, silica-charged waters and a stagnant, anoxic environment in parts of the lake were necessary conditions for the precipitation of large amounts of uranium in the lake-bottom sediments. Sediments at the Anderson mine contain plant remains and pollen that were derived from diverse vegetative zones suggesting about 1500 m of relief in the area at the time of deposition. The pollen suggests that the valley floor was semiarid and subtropical, whereas nearby mountains supported temperate deciduous forests. ?? 1990.

Direct weak localization signature with ultracold atoms: the CBS revival

NASA Astrophysics Data System (ADS)

Josse, Vincent

2016-05-01

Ultracold atomic systems in presence of disorder have attracted a lot of interest over the past decade, in particular to study the physics of Anderson localization (AL) in a renewed perspective. Landmark experiments have been demonstrated, in 1D and 3D geometries. However many challenges remain and new ideas have emerged, as for instance the search for original signatures of Anderson localization in momentum space. Here I will describe our progresses along that line where a weak localization effect has been directly observed, i.e. the Coherent Backscattering (CBS) phenomenon. In particular I will report on the recent observation of suppression and revival of CBS when a controlled dephasing kick is applied to the system. This observation demonstrates a novel and general method, introduced by T. Micklitz and coworkers, to study probe phase coherence in disordered systems by manipulating time reversal symmetry.

Superdiffusive transport and energy localization in disordered granular crystals

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

Martinez, Alejandro J.; Kevrekidis, Panagiotis G.; Porter, Mason A.

We study the spreading of initially localized excitations in one-dimensional disordered granular crystals. We thereby investigate localization phenomena in strongly nonlinear systems, which we demonstrate to be fundamentally different from localization in linear and weakly nonlinear systems. We conduct a thorough comparison of wave dynamics in chains with three different types of disorder: an uncorrelated (Anderson-like) disorder and two types of correlated disorders (which are produced by random dimer arrangements), and for two families of initial conditions: displacement perturbations and velocity perturbations. We find for strongly precompressed (i.e., weakly nonlinear) chains that the dynamics strongly depends on the initial condition.more » Furthermore, for displacement perturbations, the long-time asymptotic behavior of the second moment m ~2 has oscillations that depend on the type of disorder, with a complex trend that is markedly different from a power law and which is particularly evident for an Anderson-like disorder.« less

The Anderson localization problem, the Fermi-Pasta-Ulam paradox and the generalized diffusion approach

NASA Astrophysics Data System (ADS)

Kuzovkov, V. N.

2011-12-01

The goal of this paper is twofold. First, based on the interpretation of a quantum tight-binding model in terms of a classical Hamiltonian map, we consider the Anderson localization (AL) problem as the Fermi-Pasta-Ulam (FPU) effect in a modified dynamical system containing both stable and unstable (inverted) modes. Delocalized states in the AL are analogous to the stable quasi-periodic motion in FPU, whereas localized states are analogous to thermalization, respectively. The second aim is to use the classical Hamilton map for a simplified derivation of exact equations for the localization operator H(z). The latter was presented earlier (Kuzovkov et al 2002 J. Phys.: Condens. Matter 14 13777) treating the AL as a generalized diffusion in a dynamical system. We demonstrate that counter-intuitive results of our studies of the AL are similar to the FPU counter-intuitivity.

Information Transmission and Anderson Localization in two-dimensional networks of firing-rate neurons

NASA Astrophysics Data System (ADS)

Natale, Joseph; Hentschel, George

Firing-rate networks offer a coarse model of signal propagation in the brain. Here we analyze sparse, 2D planar firing-rate networks with no synapses beyond a certain cutoff distance. Additionally, we impose Dale's Principle to ensure that each neuron makes only or inhibitory outgoing connections. Using spectral methods, we find that the number of neurons participating in excitations of the network becomes insignificant whenever the connectivity cutoff is tuned to a value near or below the average interneuron separation. Further, neural activations exceeding a certain threshold stay confined to a small region of space. This behavior is an instance of Anderson localization, a disorder-induced phase transition by which an information channel is rendered unable to transmit signals. We discuss several potential implications of localization for both local and long-range computation in the brain. This work was supported in part by Grants JSMF/ 220020321 and NSF/IOS/1208126.

Superdiffusive transport and energy localization in disordered granular crystals

DOE PAGES

Martinez, Alejandro J.; Kevrekidis, Panagiotis G.; Porter, Mason A.

2016-02-12

We study the spreading of initially localized excitations in one-dimensional disordered granular crystals. We thereby investigate localization phenomena in strongly nonlinear systems, which we demonstrate to be fundamentally different from localization in linear and weakly nonlinear systems. We conduct a thorough comparison of wave dynamics in chains with three different types of disorder: an uncorrelated (Anderson-like) disorder and two types of correlated disorders (which are produced by random dimer arrangements), and for two families of initial conditions: displacement perturbations and velocity perturbations. We find for strongly precompressed (i.e., weakly nonlinear) chains that the dynamics strongly depends on the initial condition.more » Furthermore, for displacement perturbations, the long-time asymptotic behavior of the second moment m ~2 has oscillations that depend on the type of disorder, with a complex trend that is markedly different from a power law and which is particularly evident for an Anderson-like disorder.« less

Fabrication and characterization of disordered polymer optical fibers for transverse Anderson localization of light.

PubMed

Karbasi, Salman; Frazier, Ryan J; Mirr, Craig R; Koch, Karl W; Mafi, Arash

2013-07-29

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 μm. Initially, each strand is 200 μm in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light

PubMed Central

Karbasi, Salman; Frazier, Ryan J.; Mirr, Craig R.; Koch, Karl W.; Mafi, Arash

2013-01-01

We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 μm. Initially, each strand is 200 μm in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems. PMID:23929276

Return to Glacier Bay

USGS Publications Warehouse

Bodkin, James L.

2003-01-01

Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

Localization in one-dimensional lattices with non-nearest-neighbor hopping: Generalized Anderson and Aubry-Andre models

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

Biddle, J.; Priour, D. J. Jr.; Wang, B.

We study the quantum localization phenomena of noninteracting particles in one-dimensional lattices based on tight-binding models with various forms of hopping terms beyond the nearest neighbor, which are generalizations of the famous Aubry-Andre and noninteracting Anderson models. For the case with deterministic disordered potential induced by a secondary incommensurate lattice (i.e., the Aubry-Andre model), we identify a class of self-dual models, for which the boundary between localized and extended eigenstates are determined analytically by employing a generalized Aubry-Andre transformation. We also numerically investigate the localization properties of nondual models with next-nearest-neighbor hopping, Gaussian, and power-law decay hopping terms. We findmore » that even for these nondual models, the numerically obtained mobility edges can be well approximated by the analytically obtained condition for localization transition in the self-dual models, as long as the decay of the hopping rate with respect to distance is sufficiently fast. For the disordered potential with genuinely random character, we examine scenarios with next-nearest-neighbor hopping, exponential, Gaussian, and power-law decay hopping terms numerically. We find that the higher-order hopping terms can remove the symmetry in the localization length about the energy band center compared to the Anderson model. Furthermore, our results demonstrate that for the power-law decay case, there exists a critical exponent below which mobility edges can be found. Our theoretical results could, in principle, be directly tested in shallow atomic optical lattice systems enabling non-nearest-neighbor hopping.« less

Dynamical Localization for Discrete and Continuous Random Schrödinger Operators

NASA Astrophysics Data System (ADS)

Germinet, F.; De Bièvre, S.

We show for a large class of random Schrödinger operators Ho on and on that dynamical localization holds, i.e. that, with probability one, for a suitable energy interval I and for q a positive real, Here ψ is a function of sufficiently rapid decrease, and PI(Ho) is the spectral projector of Ho corresponding to the interval I. The result is obtained through the control of the decay of the eigenfunctions of Ho and covers, in the discrete case, the Anderson tight-binding model with Bernoulli potential (dimension ν = 1) or singular potential (ν > 1), and in the continuous case Anderson as well as random Landau Hamiltonians.

Spectral correlations in Anderson insulating wires

NASA Astrophysics Data System (ADS)

Marinho, M.; Micklitz, T.

2018-01-01

We calculate the spectral level-level correlation function of Anderson insulating wires for all three Wigner-Dyson classes. A measurement of its Fourier transform, the spectral form factor, is within reach of state-of-the-art cold atom quantum quench experiments, and we find good agreement with recent numerical simulations of the latter. Our derivation builds on a representation of the level-level correlation function in terms of a local generating function which may prove useful in other contexts.

Slow dynamics of electron glasses: The role of disorder

NASA Astrophysics Data System (ADS)

Ovadyahu, Z.

2017-04-01

We examine in this work the role of disorder in contributing to the sluggish relaxation observed in intrinsic electron glasses. Our approach is guided by several empirical observations: First and foremost, Anderson localization is a pre-requisite for observing these nonequilibrium phenomena. Secondly, sluggish relaxation appears to favor Anderson insulators with relatively large Fermi energies (hence proportionally large disorder). These observations motivated us to consider a way to measure the underlying disorder in a realistic Anderson insulator. Optical studies using a series of amorphous indium oxide (InxO ) establish a simple connection between carrier concentration and the disorder necessary to approach the metal-insulator transition from the insulating side. This is used to estimate the typical magnitude of the quenched potential fluctuation in the electron-glass phase of this system. The implications of our findings on the slow dynamics of Anderson insulators are discussed. In particular, the reason for the absence of a memory dip and the accompanying electron-glass effects in lightly-doped semiconductors emerges as a natural consequence of their weak disorder.

Kondo effect in the seven-orbital Anderson model hybridized with Γ8 conduction electrons

NASA Astrophysics Data System (ADS)

Hotta, Takashi

2018-05-01

We clarify the two-channel Kondo effect in the seven-orbital Anderson model hybridized with Γ8 conduction electrons by employing a numerical renormalization group method. From the numerical analysis for the case with two local f electrons, corresponding to Pr3+ or U4+ ion, we confirm that a residual entropy of 0.5 log 2 , a characteristic of two-channel Kondo phenomena, appears for the local Γ3 non-Kramers doublet state. For further understanding on the Γ3 state, the effective model is constructed on the basis of a j-j coupling scheme. Then, we rediscover the two-channel s-d model concerning quadrupole degrees of freedom. Finally, we briefly introduce our recent result on the two-channel Kondo effect for the case with three local f electrons.

ETR, TRA642. ETR COMPLEX NEARLY COMPLETE. CAMERA FACES NORTHWEST, PROBABLY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR, TRA-642. ETR COMPLEX NEARLY COMPLETE. CAMERA FACES NORTHWEST, PROBABLY FROM TOP DECK OF COOLING TOWER. SHADOW IS CAST BY COOLING TOWER UNITS OFF LEFT OF VIEW. HIGH-BAY REACTOR BUILDING IS SURROUNDED BY ITS ATTACHED SERVICES: ELECTRICAL (TRA-648), HEAT EXCHANGER (TRA-644 WITH U-SHAPED YARD), AND COMPRESSOR (TRA-643). THE CONTROL BUILDING (TRA-647) ON THE NORTH SIDE IS HIDDEN FROM VIEW. AT UPPER RIGHT IS MTR BUILDING, TRA-603. INL NEGATIVE NO. 56-3798. Jack L. Anderson, Photographer, 11/26/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

High-Dimensional Disorder-Driven Phenomena in Weyl Semimetals, Semiconductors, and Related Systems

NASA Astrophysics Data System (ADS)

Syzranov, Sergey V.; Radzihovsky, Leo

2018-03-01

It is commonly believed that a noninteracting disordered electronic system can undergo only the Anderson metal-insulator transition. It has been suggested, however, that a broad class of systems can display disorder-driven transitions distinct from Anderson localization that have manifestations in the disorder-averaged density of states, conductivity, and other observables. Such transitions have received particular attention in the context of recently discovered 3D Weyl and Dirac materials but have also been predicted in cold-atom systems with long-range interactions, quantum kicked rotors, and all sufficiently high-dimensional systems. Moreover, such systems exhibit unconventional behavior of Lifshitz tails, energy-level statistics, and ballistic-transport properties. Here, we review recent progress and the status of results on non-Anderson disorder-driven transitions and related phenomena.

Anderson transition in a multiply-twisted helix.

PubMed

Ugajin, R

2001-06-01

We investigated the Anderson transition in a multiply-twisted helix in which a helical chain of components, i.e., atoms or nanoclusters, is twisted to produce a doubly-twisted helix, which itself can be twisted to produce a triply-twisted helix, and so on, in which there are couplings between adjacent rounds of helices. As the strength of the on-site random potentials increases, an Anderson transition occurs, suggesting that the number of dimensions is 3 for electrons running along the multiply-twisted helix when the couplings between adjacent rounds are strong enough. If the couplings are weakened, the dimensionality becomes less, resulting in localization of electrons. The effect of random connections between adjacent rounds of helices and random magnetic fields that thread the structure is analyzed using the spectral statistics of a quantum particle.

Charge density waves in disordered media circumventing the Imry-Ma argument

DOE PAGES

Changlani, Hitesh J.; Tubman, Norm M.; Hughes, Taylor L.

2016-08-24

Two powerful theoretical predictions, Anderson localization and the Imry-Ma argument, impose significant restrictions on the phases of matter that can exist in the presence of even the smallest amount of disorder in one-dimensional systems. These predictions forbid electrically conducting states and ordered states respectively. It was thus remarkable that a mechanism to circumvent Anderson localization relying on the presence of correlated disorder was found, that is also realized in certain biomolecular systems. Here, in a similar manner, we show that the Imry-Ma argument can be circumvented, resulting in the formation of stable ordered states with discrete broken symmetries in disorderedmore » one dimensional systems. We then investigate other mechanisms by which disorder can destroy an ordered state.« less

Statistical crossover characterization of the heterotic localized-extended transition.

PubMed

Ugajin, Ryuichi

2003-07-01

We investigated the spectral statistics of a quantum particle in a superlattice consisting of a disordered layer and a clean layer, possibly accompanied by random magnetic fields. Because a disordered layer has localized states and a clean layer has extended states, our quantum system shows a heterotic phase of an Anderson insulator and a normal metal. As the ratio of the volume of these two layers changes, the spectral statistics change from Poissonian to one of the Gaussian ensembles which characterize quantum chaos. A crossover distribution specified by two parameters is introduced to distinguish the transition from an integrable system to a quantum chaotic system during the heterotic phase from an Anderson transition in which the degree of random potentials is homogenous.

Charge density waves in disordered media circumventing the Imry-Ma argument

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

Changlani, Hitesh J.; Tubman, Norm M.; Hughes, Taylor L.

Two powerful theoretical predictions, Anderson localization and the Imry-Ma argument, impose significant restrictions on the phases of matter that can exist in the presence of even the smallest amount of disorder in one-dimensional systems. These predictions forbid electrically conducting states and ordered states respectively. It was thus remarkable that a mechanism to circumvent Anderson localization relying on the presence of correlated disorder was found, that is also realized in certain biomolecular systems. Here, in a similar manner, we show that the Imry-Ma argument can be circumvented, resulting in the formation of stable ordered states with discrete broken symmetries in disorderedmore » one dimensional systems. We then investigate other mechanisms by which disorder can destroy an ordered state.« less

Topology versus Anderson localization: Nonperturbative solutions in one dimension

NASA Astrophysics Data System (ADS)

Altland, Alexander; Bagrets, Dmitry; Kamenev, Alex

2015-02-01

We present an analytic theory of quantum criticality in quasi-one-dimensional topological Anderson insulators. We describe these systems in terms of two parameters (g ,χ ) representing localization and topological properties, respectively. Certain critical values of χ (half-integer for Z classes, or zero for Z2 classes) define phase boundaries between distinct topological sectors. Upon increasing system size, the two parameters exhibit flow similar to the celebrated two-parameter flow of the integer quantum Hall insulator. However, unlike the quantum Hall system, an exact analytical description of the entire phase diagram can be given in terms of the transfer-matrix solution of corresponding supersymmetric nonlinear sigma models. In Z2 classes we uncover a hidden supersymmetry, present at the quantum critical point.

Magnetoresistance of an Anderson insulator of bosons.

PubMed

Gangopadhyay, Anirban; Galitski, Victor; Müller, Markus

2013-07-12

We study the magnetoresistance of two-dimensional bosonic Anderson insulators. We describe the change in spatial decay of localized excitations in response to a magnetic field, which is given by an interference sum over alternative tunneling trajectories. The excitations become more localized with increasing field (in sharp contrast to generic fermionic excitations which get weakly delocalized): the localization length ξ(B) is found to change as ξ(-1)(B)-ξ(-1)(0)~B(4/5). The quantum interference problem maps onto the classical statistical mechanics of directed polymers in random media (DPRM). We explain the observed scaling using a simplified droplet model which incorporates the nontrivial DPRM exponents. Our results have implications for a variety of experiments on magnetic-field-tuned superconductor-to-insulator transitions observed in disordered films, granular superconductors, and Josephson junction arrays, as well as for cold atoms in artificial gauge fields.

Perfect absorption in nanotextured thin films via Anderson-localized photon modes

NASA Astrophysics Data System (ADS)

Aeschlimann, Martin; Brixner, Tobias; Differt, Dominik; Heinzmann, Ulrich; Hensen, Matthias; Kramer, Christian; Lükermann, Florian; Melchior, Pascal; Pfeiffer, Walter; Piecuch, Martin; Schneider, Christian; Stiebig, Helmut; Strüber, Christian; Thielen, Philip

2015-10-01

The enhancement of light absorption in absorber layers is crucial in a number of applications, including photovoltaics and thermoelectrics. The efficient use of natural resources and physical constraints such as limited charge extraction in photovoltaic devices require thin but efficient absorbers. Among the many different strategies used, light diffraction and light localization at randomly nanotextured interfaces have been proposed to improve absorption. Although already exploited in commercial devices, the enhancement mechanism for devices with nanotextured interfaces is still subject to debate. Using coherent two-dimensional nanoscopy and coherent light scattering, we demonstrate the existence of localized photonic states in nanotextured amorphous silicon layers as used in commercial thin-film solar cells. Resonant absorption in these states accounts for the enhanced absorption in the long-wavelength cutoff region. Our observations establish that Anderson localization—that is, strong localization—is a highly efficient resonant absorption enhancement mechanism offering interesting opportunities for the design of efficient future absorber layers.

Revision of a local magnitude relation for South Korea

NASA Astrophysics Data System (ADS)

Sheen, D. H.; Seo, K. J.; Oh, J.; Kim, S.; Kang, T. S.; Rhie, J.

2017-12-01

A local magnitude relation in South Korea is revised using synthetic Wood-Anderson seismograms from local earthquakes in the distance range of 10-600 km recorded by broadband seismic networks, operated by the Korea Institute of Geoscience and Mineral Resources (KIGAM) and the Korea Meteorological Administration (KMA) between 2001 and 2016. The magnitudes of the earthquakes ranged from ML 2.0 to 5.8 based on the catalog of the KMA. Total numbers of events and seismic records are about 500 and 10,000, respectively. In order to minimize the location error, inland earthquakes were relocated based on manual picks of P and S arrivals using 1-D velocity model for South Korea developed by a trans-dimensional hierarchical Bayesian inversion. Wood-Anderson peak amplitudes measured on the records whose signal-to-noise ratios are greater than 3.0 and were inverted for the attenuation curve by parametric and non-parametric least-squares inversion methods. The discussion on the comparison of the resulting local magnitude relationships will also be addressed.

A perspective on quantum integrability in many-body-localized and Yang-Baxter systems

NASA Astrophysics Data System (ADS)

Moore, Joel E.

2017-10-01

Two of the most active areas in quantum many-particle dynamics involve systems with an unusually large number of conservation laws. Many-body-localized systems generalize ideas of Anderson localization by disorder to interacting systems. While localization still exists with interactions and inhibits thermalization, the interactions between conserved quantities lead to some dramatic differences from the Anderson case. Quantum integrable models such as the XXZ spin chain or Bose gas with delta-function interactions also have infinite sets of conservation laws, again leading to modifications of conventional thermalization. A practical way to treat the hydrodynamic evolution from local equilibrium to global equilibrium in such models is discussed. This paper expands upon a presentation at a discussion meeting of the Royal Society on 7 February 2017. The work described was carried out with a number of collaborators, including Jens Bardarson, Vir Bulchandani, Roni Ilan, Christoph Karrasch, Siddharth Parameswaran, Frank Pollmann and Romain Vasseur. This article is part of the themed issue 'Breakdown of ergodicity in quantum systems: from solids to synthetic matter'.

Scaling analysis of Anderson localizing optical fibers

NASA Astrophysics Data System (ADS)

Abaie, Behnam; Mafi, Arash

2017-02-01

Anderson localizing optical fibers (ALOF) enable a novel optical waveguiding mechanism; if a narrow beam is scanned across the input facet of the disordered fiber, the output beam follows the transverse position of the incoming wave. Strong transverse disorder induces several localized modes uniformly spread across the transverse structure of the fiber. Each localized mode acts like a transmission channel which carries a narrow input beam along the fiber without transverse expansion. Here, we investigate scaling of transverse size of the localized modes of ALOF with respect to transverse dimensions of the fiber. Probability density function (PDF) of the mode-area is applied and it is shown that PDF converges to a terminal shape at transverse dimensions considerably smaller than the previous experimental implementations. Our analysis turns the formidable numerical task of ALOF simulations into a much simpler problem, because the convergence of mode-area PDF to a terminal shape indicates that a much smaller disordered fiber, compared to previous numerical and experimental implementations, provides all the statistical information required for the precise analysis of the fiber.

Caste, Class and the Love-Marriage: Social Change in India

ERIC Educational Resources Information Center

Corwin, Lauren A.

1977-01-01

The present study of a small town in rural West Bengal, India, reveals a number of "love-marriages" involving individuals from castes of distinctly different ranks in the local caste hierarchy. Despite the prevailing rule of caste endogamy, inter-caste couples appear to face little difficulty. (Author)

Study of multiband disordered systems using the typical medium dynamical cluster approximation

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

Zhang, Yi; Terletska, Hanna; Moore, C.

We generalize the typical medium dynamical cluster approximation to multiband disordered systems. Using our extended formalism, we perform a systematic study of the nonlocal correlation effects induced by disorder on the density of states and the mobility edge of the three-dimensional two-band Anderson model. We include interband and intraband hopping and an intraband disorder potential. Our results are consistent with those obtained by the transfer matrix and the kernel polynomial methods. We also apply the method to K xFe 2-ySe 2 with Fe vacancies. Despite the strong vacancy disorder and anisotropy, we find the material is not an Anderson insulator.more » Moreover our results demonstrate the application of the typical medium dynamical cluster approximation method to study Anderson localization in real materials.« less

Study of multiband disordered systems using the typical medium dynamical cluster approximation

DOE PAGES

Zhang, Yi; Terletska, Hanna; Moore, C.; ...

2015-11-06

We generalize the typical medium dynamical cluster approximation to multiband disordered systems. Using our extended formalism, we perform a systematic study of the nonlocal correlation effects induced by disorder on the density of states and the mobility edge of the three-dimensional two-band Anderson model. We include interband and intraband hopping and an intraband disorder potential. Our results are consistent with those obtained by the transfer matrix and the kernel polynomial methods. We also apply the method to K xFe 2-ySe 2 with Fe vacancies. Despite the strong vacancy disorder and anisotropy, we find the material is not an Anderson insulator.more » Moreover our results demonstrate the application of the typical medium dynamical cluster approximation method to study Anderson localization in real materials.« less

Dielectric response of Anderson and pseudogapped insulators

NASA Astrophysics Data System (ADS)

Feigel’man, M. V.; Ivanov, D. A.; Cuevas, E.

2018-05-01

Using a combination of analytic and numerical methods, we study the polarizability of a (non-interacting) Anderson insulator in one-, two-, and three-dimensions and demonstrate that, in a wide range of parameters, it scales proportionally to the square of the localization length, contrary to earlier claims based on the effective-medium approximation. We further analyze the effect of electron–electron interactions on the dielectric constant in quasi-1D, quasi-2D and 3D materials with large localization length, including both Coulomb repulsion and phonon-mediated attraction. The phonon-mediated attraction (in the pseudogapped state on the insulating side of the superconductor-insulator transition) produces a correction to the dielectric constant, which may be detected from a linear response of a dielectric constant to an external magnetic field.

Novel colloidal materials from functionalized polyoxometalates

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

Swenson, LaSalle; Orozco, Jose C.; Liu, Yuzi

Here, novel colloidal materials were prepared for the first time from the organo-functionalized Anderson structure polyoxometalate species [NaV IV 6O 6{(OCH 2CH 2) 2N(CH 2CH 2OH)} 6]Cl·H 2O and the mixed-addenda Keggin structure polyoxometalate, K 4(PVW 11O 40). The materials were characterized by SEM, TGA, FTIR and UV-vis spectroscopy. The colloidal materials are readily separated from suspension in the form of redistributable micrometer-scale monoliths, which may be considered a type of POM heterogenation. The monoliths are insoluble in low polarity media and lower aliphatic alcohols and readily form thin-films (δ < 100 um) by solvent casting.

Novel colloidal materials from functionalized polyoxometalates

DOE PAGES

Swenson, LaSalle; Orozco, Jose C.; Liu, Yuzi; ...

2017-07-13

Here, novel colloidal materials were prepared for the first time from the organo-functionalized Anderson structure polyoxometalate species [NaV IV 6O 6{(OCH 2CH 2) 2N(CH 2CH 2OH)} 6]Cl·H 2O and the mixed-addenda Keggin structure polyoxometalate, K 4(PVW 11O 40). The materials were characterized by SEM, TGA, FTIR and UV-vis spectroscopy. The colloidal materials are readily separated from suspension in the form of redistributable micrometer-scale monoliths, which may be considered a type of POM heterogenation. The monoliths are insoluble in low polarity media and lower aliphatic alcohols and readily form thin-films (δ < 100 um) by solvent casting.

Normal yeast flora of the upper digestive tract of some wild columbids

USGS Publications Warehouse

Kocan, R.M.; Hasenclever, H.F.

1972-01-01

Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

Numerical renormalization group calculation of impurity internal energy and specific heat of quantum impurity models

NASA Astrophysics Data System (ADS)

Merker, L.; Costi, T. A.

2012-08-01

We introduce a method to obtain the specific heat of quantum impurity models via a direct calculation of the impurity internal energy requiring only the evaluation of local quantities within a single numerical renormalization group (NRG) calculation for the total system. For the Anderson impurity model we show that the impurity internal energy can be expressed as a sum of purely local static correlation functions and a term that involves also the impurity Green function. The temperature dependence of the latter can be neglected in many cases, thereby allowing the impurity specific heat Cimp to be calculated accurately from local static correlation functions; specifically via Cimp=(∂Eionic)/(∂T)+(1)/(2)(∂Ehyb)/(∂T), where Eionic and Ehyb are the energies of the (embedded) impurity and the hybridization energy, respectively. The term involving the Green function can also be evaluated in cases where its temperature dependence is non-negligible, adding an extra term to Cimp. For the nondegenerate Anderson impurity model, we show by comparison with exact Bethe ansatz calculations that the results recover accurately both the Kondo induced peak in the specific heat at low temperatures as well as the high-temperature peak due to the resonant level. The approach applies to multiorbital and multichannel Anderson impurity models with arbitrary local Coulomb interactions. An application to the Ohmic two-state system and the anisotropic Kondo model is also given, with comparisons to Bethe ansatz calculations. The approach could also be of interest within other impurity solvers, for example, within quantum Monte Carlo techniques.

Evaluation of the Malaga Bend salinity alleviation project, Eddy County, New Mexico

USGS Publications Warehouse

Kunkler, J.L.

1980-01-01

In an effort to reduce the flow of brine springs in the Malaga Bend reach of the Pecos River in southeastern New Mexico, brine was pumped from an aquifer underlying the Malaga Bend reach to a local depression known as Anderson Lake. The attempt to improve the quality of river water with this experiment was not successful because brine leakage from Anderson Lake to the nearby Pecos River through permeable subsurface rocks was greater than the previous natural spring inflow. Brine leakage from Anderson Lake from July 22, 1963, through September 30, 1968, was estimated by evaporation-pan, salt accumulation, and dissolved-constituent methods. The leakage values given by these three methods are in good agreement with each other and indicate that between the dates given, leakage from the lake was about 2 ,300 acre-feet, compared with a brine inflow to the lake of about 3,690 acre-feet. Other data indicate that pumping from the brine aquifer greatly reduced the natural inflow from brine springs to the Malaga Bend reach. The rate of brine leakage from Anderson Lake is probably greater than might be expected from other brine lakes in the area because the cavities in the bottom of the lake apparently are in hydrologic connection with the Pecos River. This connection is shown by a relation between the salinity of the Pecos River and the reservoir stage of Anderson Lake. (USGS)

Local ventilation solution for large, warm emission sources.

PubMed

Kulmala, Ilpo; Hynynen, Pasi; Welling, Irma; Säämänen, Arto

2007-01-01

In a foundry casting line, contaminants are released from a large area. Casting fumes include both volatile and particulate compounds. The volatile fraction contains hydrocarbons, whereas the particulate fraction mostly comprises a mixture of vaporized metal fumes. Casting fumes lower the air quality in foundries. The design of local ventilation for the casting area is a challenging task, because of the large casting area and convection plumes from warm moulds. A local ventilation solution for the mould casting area was designed and dimensioned with the aid of computational fluid dynamic (CFD) calculations. According to the calculations, the most efficient solution was a push-pull ventilation system. The prototype of the push-pull system was built and tested in actual operation at the foundry. The push flow was generated by a free plane jet that blew across the 10 m wide casting area towards an exhaust hood on the opposite side of the casting lines. The capture efficiency of the prototype was determined by the tracer gas method. The measured capture efficiencies with push jet varied between 40 and 80%, depending on the distance between the source and the exhaust. With the aid of the push flow, the average capture efficiency was increased from 40 (without jet) to 60%.

Effects of correlated hybridization in the single-impurity Anderson model

NASA Astrophysics Data System (ADS)

Líbero, Valter; Veiga, Rodrigo

2013-03-01

The development of new materials often dependents on the theoretical foundations which study the microscopic matter, i.e., the way atoms interact and create distinct configurations. Among the interesting materials, those with partially filled d or f orbitals immersed in nonmagnetic metals have been described by the Anderson model, which takes into account Coulomb correlation (U) when a local level (energy Ed) is doubled occupied, and an electronic hybridization between local levels and conduction band states. In addition, here we include a correlated hybridization term, which depends on the local-level occupation number involved. This term breaks particle-hole symmetry (even when U + 2Ed = 0), enhances charge fluctuations on local levels and as a consequence strongly modifies the crossover between the Hamiltonian fixed-points, even suppressing one or other. We exemplify these behaviors showing data obtained from the Numerical Renormalization Group (NRG) computation for the impurity temperature-dependent specific heat, entropy and magnetic susceptibility. The interleaving procedure is used to recover the continuum spectrum after the NRG-logarithmic discretization of the conduction band. Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP.

Localization effects in radiationally disordered high-temperature superconductors: Theoretical interpretation

NASA Technical Reports Server (NTRS)

Goshchitskii, B. N.; Davydov, S. A.; Karkin, A. E.; Mirmelstein, A. V.; Sadovskii, M. V.

1990-01-01

Theoretical interpretation of recent experiments on radiationally disordered high-temperature superconductors is presented, based on the concepts of mutual interplay of Anderson localization and superconductivity. Microscopic derivation of Ginzburg-Landau coefficients for the quasi-two-dimensional system in the vicinity of localization transition is given in the framework of the self-consistent theory of localization. The 'minimal metallic conductivity' for the quasi-two-dimensional case is enhanced due to a small overlap of electronic states on the nearest neighbor conducting planes. This leads to a stronger influence of localization effects than in ordinary (three-dimensional) superconductors. From this point of view even the initial samples of high-temperature superconductors are already very close to Anderson transition. Anomalies of H(c2) are also analyzed, explaining the upward curvature of H(c2)(T) and apparent independence of dH(c2)/dT (T = T(sub c)) on the degree of disorder as due to localization effects. Researchers discuss the possible reasons of fast T(sub c) degradation due to the enhanced Coulomb effects caused by the disorder induced decrease of localization length. The appearance and growth of localized magnetic moments is also discussed. The disorder dependence of localization length calculated from the experimental data on conductivity correlates reasonably with the theoretical criterion for suppression of superconductivity in the system with localized electronic states.

76 FR 63936 - Agency Information Collection Activities: Proposed Collection; Comment Request; PrepCAST

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

...CAST AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice. SUMMARY: The Federal Emergency...CAST) (formerly known as the National Incident Management System Compliance Assistance Support Tool (NIMSCAST)). PrepCAST is a self-assessment tool for State, territorial, Tribal, and local governments to...

Kolmogorov Turbulence Defeated by Anderson Localization for a Bose-Einstein Condensate in a Sinai-Oscillator Trap

NASA Astrophysics Data System (ADS)

Ermann, Leonardo; Vergini, Eduardo; Shepelyansky, Dima L.

2017-08-01

We study the dynamics of a Bose-Einstein condensate in a Sinai-oscillator trap under a monochromatic driving force. Such a trap is formed by a harmonic potential and a repulsive disk located in the center vicinity corresponding to the first experiments of condensate formation by Ketterle and co-workers in 1995. We allow that the external driving allows us to model the regime of weak wave turbulence with the Kolmogorov energy flow from low to high energies. We show that in a certain regime of weak driving and weak nonlinearity such a turbulent energy flow is defeated by the Anderson localization that leads to localization of energy on low energy modes. This is in a drastic contrast to the random phase approximation leading to energy flow to high modes. A critical threshold is determined above which the turbulent flow to high energies becomes possible. We argue that this phenomenon can be studied with ultracold atoms in magneto-optical traps.

Kolmogorov Turbulence Defeated by Anderson Localization for a Bose-Einstein Condensate in a Sinai-Oscillator Trap.

PubMed

Ermann, Leonardo; Vergini, Eduardo; Shepelyansky, Dima L

2017-08-04

We study the dynamics of a Bose-Einstein condensate in a Sinai-oscillator trap under a monochromatic driving force. Such a trap is formed by a harmonic potential and a repulsive disk located in the center vicinity corresponding to the first experiments of condensate formation by Ketterle and co-workers in 1995. We allow that the external driving allows us to model the regime of weak wave turbulence with the Kolmogorov energy flow from low to high energies. We show that in a certain regime of weak driving and weak nonlinearity such a turbulent energy flow is defeated by the Anderson localization that leads to localization of energy on low energy modes. This is in a drastic contrast to the random phase approximation leading to energy flow to high modes. A critical threshold is determined above which the turbulent flow to high energies becomes possible. We argue that this phenomenon can be studied with ultracold atoms in magneto-optical traps.

Topological Anderson insulator phase in a Dirac-semimetal thin film

NASA Astrophysics Data System (ADS)

Chen, Rui; Xu, Dong-Hui; Zhou, Bin

2017-06-01

The recently discovered topological Dirac semimetal represents a new exotic quantum state of matter. Topological Dirac semimetals can be viewed as three-dimensional analogues of graphene, in which the Dirac nodes are protected by crystalline symmetry. It has been found that the quantum confinement effect can gap out Dirac nodes and convert Dirac semimetal to a band insulator. The band insulator is either a normal insulator or quantum spin Hall insulator, depending on the thin-film thickness. We present the study of disorder effects in a thin film of Dirac semimetals. It is found that moderate Anderson disorder strength can drive a topological phase transition from a normal band insulator to a topological Anderson insulator in a Dirac-semimetal thin film. The numerical calculation based on the model parameters of Dirac semimetal Na3Bi shows that in the topological Anderson insulator phase, a quantized conductance plateau occurs in the bulk gap of the band insulator, and the distributions of local currents further confirm that the quantized conductance plateau arises from the helical edge states induced by disorder. Finally, an effective medium theory based on the Born approximation fits the numerical data.

Effect of impurities of selenium and iron on the Anderson localization of 1T-TaS 2

NASA Astrophysics Data System (ADS)

Ōnuki, Y.; Inada, R.; Tanuma, S.

1980-01-01

The temperature dependence of electrical resistivities θ( T) of 1T-TaS 2, 1T-TaS 2- xSe x and 1T-Fe xTa 1- xS 2 is found to be θ( T) ∝ exp( T0/ T) 1/n in the temperature range of 4 K to the measured lowest temperature, 0.1 K, showing the variable range hopping of Anderson localized states. The n-value is nearly 3 for selenium doping and nearly 2 for non-doping and iron doping. The positive magnetoresistance, which is sizable only in the temperature range of 2 K to 0.5 K in 1T-TaS 2, is found to be remarkably enhanced by the selenium doping, while the tendency is reversed by the iron doping.

High Electrical Conductivity of Single Metal-Organic Chains.

PubMed

Ares, Pablo; Amo-Ochoa, Pilar; Soler, José M; Palacios, Juan José; Gómez-Herrero, Julio; Zamora, Félix

2018-05-01

Molecular wires are essential components for future nanoscale electronics. However, the preparation of individual long conductive molecules is still a challenge. MMX metal-organic polymers are quasi-1D sequences of single halide atoms (X) bridging subunits with two metal ions (MM) connected by organic ligands. They are excellent electrical conductors as bulk macroscopic crystals and as nanoribbons. However, according to theoretical calculations, the electrical conductance found in the experiments should be even higher. Here, a novel and simple drop-casting procedure to isolate bundles of few to single MMX chains is demonstrated. Furthermore, an exponential dependence of the electrical resistance of one or two MMX chains as a function of their length that does not agree with predictions based on their theoretical band structure is reported. This dependence is attributed to strong Anderson localization originated by structural defects. Theoretical modeling confirms that the current is limited by structural defects, mainly vacancies of iodine atoms, through which the current is constrained to flow. Nevertheless, measurable electrical transport along distances beyond 250 nm surpasses that of all other molecular wires reported so far. This work places in perspective the role of defects in 1D wires and their importance for molecular electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ginzburg-Landau expansion in strongly disordered attractive Anderson-Hubbard model

NASA Astrophysics Data System (ADS)

Kuchinskii, E. Z.; Kuleeva, N. A.; Sadovskii, M. V.

2017-07-01

We have studied disordering effects on the coefficients of Ginzburg-Landau expansion in powers of superconducting order parameter in the attractive Anderson-Hubbard model within the generalized DMFT+Σ approximation. We consider the wide region of attractive potentials U from the weak coupling region, where superconductivity is described by BCS model, to the strong coupling region, where the superconducting transition is related with Bose-Einstein condensation (BEC) of compact Cooper pairs formed at temperatures essentially larger than the temperature of superconducting transition, and a wide range of disorder—from weak to strong, where the system is in the vicinity of Anderson transition. In the case of semielliptic bare density of states, disorder's influence upon the coefficients A and B of the square and the fourth power of the order parameter is universal for any value of electron correlation and is related only to the general disorder widening of the bare band (generalized Anderson theorem). Such universality is absent for the gradient term expansion coefficient C. In the usual theory of "dirty" superconductors, the C coefficient drops with the growth of disorder. In the limit of strong disorder in BCS limit, the coefficient C is very sensitive to the effects of Anderson localization, which lead to its further drop with disorder growth up to the region of the Anderson insulator. In the region of BCS-BEC crossover and in BEC limit, the coefficient C and all related physical properties are weakly dependent on disorder. In particular, this leads to relatively weak disorder dependence of both penetration depth and coherence lengths, as well as of related slope of the upper critical magnetic field at superconducting transition, in the region of very strong coupling.

Cardiovascular cast model fabrication and casting effectiveness evaluation in fetus with severe congenital heart disease or normal heart.

PubMed

Wang, Yu; Cao, Hai-yan; Xie, Ming-xing; He, Lin; Han, Wei; Hong, Liu; Peng, Yuan; Hu, Yun-fei; Song, Ben-cai; Wang, Jing; Wang, Bin; Deng, Cheng

2016-04-01

To investigate the application and effectiveness of vascular corrosion technique in preparing fetal cardiovascular cast models, 10 normal fetal heart specimens with other congenital disease (control group) and 18 specimens with severe congenital heart disease (case group) from induced abortions were enrolled in this study from March 2013 to June 2015 in our hospital. Cast models were prepared by injecting casting material into vascular lumen to demonstrate real geometries of fetal cardiovascular system. Casting effectiveness was analyzed in terms of local anatomic structures and different anatomical levels (including overall level, atrioventricular and great vascular system, left-sided and right-sided heart), as well as different trimesters of pregnancy. In our study, all specimens were successfully casted. Casting effectiveness analysis of local anatomic structures showed a mean score from 1.90±1.45 to 3.60±0.52, without significant differences between case and control groups in most local anatomic structures except left ventricle, which had a higher score in control group (P=0.027). Inter-group comparison of casting effectiveness in different anatomical levels showed no significant differences between the two groups. Intra-group comparison also revealed undifferentiated casting effectiveness between atrioventricular and great vascular system, or left-sided and right-sided heart in corresponding group. Third-trimester group had a significantly higher perfusion score in great vascular system than second-trimester group (P=0.046), while the other anatomical levels displayed no such difference. Vascular corrosion technique can be successfully used in fabrication of fetal cardiovascular cast model. It is also a reliable method to demonstrate three-dimensional anatomy of severe congenital heart disease and normal heart in fetus.

Posterior Temporary Fixation Versus Nonoperative Treatment for Anderson-D'Alonzo Type III Odontoid Fractures: Functional Computed Tomography Evaluation of C1-C2 Rotation.

PubMed

Guo, Qunfeng; Wang, Liang; Lu, Xuhua; Guo, Xiang; Ni, Bin

2017-04-01

To evaluate differences in radiologic and functional outcomes between C1-C2 posterior temporary fixation (PTF) and cephalocervicothoracic cast fixation for type III odontoid fractures. Data from 13 patients who underwent PTF and 13 cases who underwent cephalocervicothoracic cast fixation due to fresh type III odontoid fractures were reviewed retrospectively. All patients with fracture healing underwent a functional computed tomography scan at the final follow-up to evaluate the range of motion in C1-C2 rotation. Functional outcomes were evaluated in the form of visual analog scale for neck pain, neck stiffness, patient satisfaction, and Neck Disability Index. The outcomes were compared between the 2 groups. At the final follow up, all 26 patients achieved healing of their fractures. There were no complications associated with either treatment. The left-to-right ranges of motion of C1-C2 rotation were 41.9° ± 11.9° in the PTF group and 43.5° ± 12.0° in the cephalocervicothoracic cast fixation group. There was no statistical difference between the 2 groups regarding the C1-C2 rotation angle (P > 0.05). There also were no significant differences between 2 groups in functional outcomes evaluated by visual analog scale for neck pain, neck stiffness, Neck Disability Index, and patient satisfaction (all P > 0.05). The outcomes of PTF and cephalocervicothoracic cast fixation were comparable in the treatment of type III odontoid fractures. For type III odontoid fractures that cannot be managed by nonoperative fixation or anterior screw fixation, PTF may be the treatment of choice, because it spares the motion of the C1-C2 complex. Copyright © 2016 Elsevier Inc. All rights reserved.

Exploring the JIMP Concept: Literature Review (Examen du Concept IIMP: Analyse Documentaire)

DTIC Science & Technology

2010-02-01

publicly giving a cheque to a local charity could be problem if the local person accepting the cheque is a criminal in the eyes of the local citizens. Such...misplaced or even irresponsible in the eyes of some military personnel. Another way of framing this problem is that personnel within each system are...inconsistencies have the potential to undermine the credibility and effectiveness of militaries in the eyes of local populations. Specifically, Anderson, a

Interbasin flow in the Great Basin with special reference to the southern Funeral Mountains and the source of Furnace Creek springs, Death Valley, California, U.S.

USGS Publications Warehouse

Belcher, W.R.; Bedinger, M.S.; Back, J.T.; Sweetkind, D.S.

2009-01-01

Interbasin flow in the Great Basin has been established by scientific studies during the past century. While not occurring uniformly between all basins, its occurrence is common and is a function of the hydraulic gradient between basins and hydraulic conductivity of the intervening rocks. The Furnace Creek springs in Death Valley, California are an example of large volume springs that are widely accepted as being the discharge points of regional interbasin flow. The flow path has been interpreted historically to be through consolidated Paleozoic carbonate rocks in the southern Funeral Mountains. This work reviews the preponderance of evidence supporting the concept of interbasin flow in the Death Valley region and the Great Basin and addresses the conceptual model of pluvial and recent recharge [Nelson, S.T., Anderson, K., Mayo, A.L., 2004. Testing the interbasin flow hypothesis at Death Valley, California. EOS 85, 349; Anderson, K., Nelson, S., Mayo, A., Tingey, D., 2006. Interbasin flow revisited: the contribution of local recharge to high-discharge springs, Death Valley, California. Journal of Hydrology 323, 276-302] as the source of the Furnace Creek springs. We find that there is insufficient modern recharge and insufficient storage potential and permeability within the basin-fill units in the Furnace Creek basin for these to serve as a local aquifer. Further, the lack of high sulfate content in the spring waters argues against significant flow through basin-fill sediments and instead suggests flow through underlying consolidated carbonate rocks. The maximum temperature of the spring discharge appears to require deep circulation through consolidated rocks; the Tertiary basin fill is of insufficient thickness to generate such temperatures as a result of local fluid circulation. Finally, the stable isotope data and chemical mass balance modeling actually support the interbasin flow conceptual model rather than the alternative presented in Nelson et al. [Nelson, S.T., Anderson, K., Mayo, A.L., 2004. Testing the interbasin flow hypothesis at Death Valley, California. EOS 85, 349] and Anderson et al. [Anderson, K., Nelson, S., Mayo, A., Tingey, D., 2006. Interbasin flow revisited: the contribution of local recharge to high-discharge springs, Death Valley, California. Journal of Hydrology 323, 276-302]. In light of these inconsistencies, interbasin flow is the only readily apparent explanation for the large spring discharges at Furnace Creek and, in our view, is the likely explanation for most large volume, low elevation springs in the Great Basin. An understanding of hydrogeologic processes that control the rate and direction of ground-water flow in eastern and central Nevada is necessary component of regional water-resource planning and management of alluvial and bedrock aquifers.

Non-Fermi glasses: fractionalizing electrons at finite energy density

NASA Astrophysics Data System (ADS)

Parameswaran, Siddharth; Gopalakrishnan, Sarang

Non-Fermi liquids are metals that cannot be adiabatically deformed into free fermion states. We argue for the existence of ``non-Fermi glasses,'' which are phases of interacting disordered fermions that are fully many-body localized, yet cannot be deformed into an Anderson insulator without an eigenstate phase transition. We explore the properties of such non-Fermi glasses, focusing on a specific solvable example. At high temperature, non-Fermi glasses have qualitatively similar spectral features to Anderson insulators. We identify a diagnostic, based on ratios of correlation functions, that sharply distinguishes between the two phases even at infinite temperature. We argue that our results and diagnostic should generically apply to the high-temperature behavior of the many-body localized descendants of fractionalized phases. S.A.P. is supported by NSF Grant DMR-1455366 and a UC President's Research Catalyst Award CA-15-327861, and S.G. by the Burke Institute at Caltech.

Focal Reduction in Cardiac 123I-Metaiodobenzylguanidine Uptake in Patients With Anderson-Fabry Disease.

PubMed

Yamamoto, Saori; Suzuki, Hideaki; Sugimura, Koichiro; Tatebe, Shunsuke; Aoki, Tatsuo; Miura, Masanobu; Yaoita, Nobuhiro; Sato, Haruka; Kozu, Katuya; Ota, Hideki; Takanami, Kentaro; Takase, Kei; Shimokawa, Hiroaki

2016-11-25

It remains to be elucidated whether cardiac sympathetic nervous activity is impaired in patients with Anderson-Fabry disease (AFD).Methods and Results:We performed 123 I-meta-iodobenzylguanidine (MIBG) scintigraphy and gadolinium-enhanced cardiovascular magnetic resonance (CMR) in 5 AFD patients. MIBG uptake in the inferolateral wall, where wall thinning and delayed enhancement were noted on CMR, was significantly lower compared with the anteroseptal wall. The localized reduction in MIBG uptake was also noted in 2 patients with no obvious abnormal findings on CMR. Cardiac sympathetic nervous activity is impaired in AFD before development of structural myocardial abnormalities. (Circ J 2016; 80: 2550-2551).

Quantum evolution: The case of weak localization for a 3D alloy-type Anderson model and application to Hamiltonian based quantum computation

NASA Astrophysics Data System (ADS)

Cao, Zhenwei

Over the years, people have found Quantum Mechanics to be extremely useful in explaining various physical phenomena from a microscopic point of view. Anderson localization, named after physicist P. W. Anderson, states that disorder in a crystal can cause non-spreading of wave packets, which is one possible mechanism (at single electron level) to explain metal-insulator transitions. The theory of quantum computation promises to bring greater computational power over classical computers by making use of some special features of Quantum Mechanics. The first part of this dissertation considers a 3D alloy-type model, where the Hamiltonian is the sum of the finite difference Laplacian corresponding to free motion of an electron and a random potential generated by a sign-indefinite single-site potential. The result shows that localization occurs in the weak disorder regime, i.e., when the coupling parameter lambda is very small, for energies E ≤ --Clambda 2. The second part of this dissertation considers adiabatic quantum computing (AQC) algorithms for the unstructured search problem to the case when the number of marked items is unknown. In an ideal situation, an explicit quantum algorithm together with a counting subroutine are given that achieve the optimal Grover speedup over classical algorithms, i.e., roughly speaking, reduce O(2n) to O(2n/2), where n is the size of the problem. However, if one considers more realistic settings, the result shows this quantum speedup is achievable only under a very rigid control precision requirement (e.g., exponentially small control error).

Verification of Anderson Superexchange in MnO via Magnetic Pair Distribution Function Analysis and ab initio Theory

NASA Astrophysics Data System (ADS)

Frandsen, Benjamin A.; Brunelli, Michela; Page, Katharine; Uemura, Yasutomo J.; Staunton, Julie B.; Billinge, Simon J. L.

2016-05-01

We present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ˜1 nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominated by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. The Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.

Effect of mold designs on molten metal behaviour in high-pressure die casting

NASA Astrophysics Data System (ADS)

Ibrahim, M. D.; Rahman, M. R. A.; Khan, A. A.; Mohamad, M. R.; Suffian, M. S. Z. M.; Yunos, Y. S.; Wong, L. K.; Mohtar, M. Z.

2017-04-01

This paper presents a research study conducted in a local automotive component manufacturer that produces aluminium alloy steering housing local and global markets. This study is to investigate the effect of design modification of mold in die casting as to improve the production rate. Design modification is carried out on the casting shot of the mold. Computer flow simulation was carried out to study the flow of molten metal in the mold with respect to the mold design modification. The design parameters of injection speed, die temperature and clamping force has been included in the study. The result of the simulation showed that modifications of casting shot give significant impact towards the molten flow behaviour in casting process. The capabilities and limitations of die casting process simulation to conduct defect analysis had been optimized. This research will enhance the efficiency of the mass production of the industry of die casting with the understanding of defect analysis, which lies on the modification of the mold design, a way early in its stages of production.

Non-conventional Anderson localization in a matched quarter stack with metamaterials

NASA Astrophysics Data System (ADS)

Torres-Herrera, E. J.; Izrailev, F. M.; Makarov, N. M.

2013-05-01

We study the problem of non-conventional Anderson localization emerging in bilayer periodic-on-average structures with alternating layers of materials, with positive and negative refraction indices na and nb. Attention is paid to the model of the so-called quarter stack with perfectly matched layers (the same unperturbed by disorder impedances, Za = Zb, and optical path lengths, nada = |nb|db, with da and db being the thicknesses of basic layers). As was recently numerically discovered, in such structures with weak fluctuations of refractive indices (compositional disorder), the localization length Lloc is enormously large in comparison to the conventional localization occurring in the structures with positive refraction indices only. In this paper we develop a new approach, which allows us to derive the expression for Lloc for weak disorder and any wave frequency ω. In the limit ω → 0 one gets a quite specific dependence, L-1loc∝σ4ω8, which is obtained within the fourth order of perturbation theory. We also analyze the interplay between two types of disorder, when in addition to the fluctuations of na and nb, the thicknesses da and db slightly fluctuate as well (positional disorder). We show how conventional localization recovers with the addition of positional disorder.

Impurity-directed transport within a finite disordered lattice

NASA Astrophysics Data System (ADS)

Magnetta, Bradley J.; Ordonez, Gonzalo; Garmon, Savannah

2018-02-01

We consider a finite, disordered 1D quantum lattice with a side-attached impurity. We study theoretically the transport of a single electron from the impurity into the lattice, at zero temperature. The transport is dominated by Anderson localization and, in general, the electron motion has a random character due to the lattice disorder. However, we show that by adjusting the impurity energy the electron can attain quasi-periodic motions, oscillating between the impurity and a small region of the lattice. This region corresponds to the spatial extent of a localized state with an energy matched by that of the impurity. By precisely tuning the impurity energy, the electron can be set to oscillate between the impurity and a region far from the impurity, even distances larger than the Anderson localization length. The electron oscillations result from the interference of hybridized states, which have some resemblance to Pendry's necklace states (Pendry, 1987) [21]. The dependence of the electron motion on the impurity energy gives a potential mechanism for selectively routing an electron towards different regions of a 1D disordered lattice.

Anderson localized modes in a disordered glass optical fiber

NASA Astrophysics Data System (ADS)

Karbasi, Salman; Hosseini, Seyedrasoul; Koch, Karl W.; Hawkins, Thomas; Ballato, John; Mafi, Arash

2014-02-01

A beam of light can propagate in a time-invariant transversely disordered waveguide because of transverse Anderson localization. We developed a disordered glass optical ber from a porous artisan glass (satin quartz). The refractive index pro le of the disordered glass optical ber is composed of a non-uniform distribution of air voids which can be approximated as longitudinally invariant. The ll-fraction of air voids is higher at the regions closer to the boundary compared with the central regions. The experimental results show that the beam radius of a localized beam is smaller at the regions closer to the boundary than the one at the central regions. In order to understand the reason behind these observations, the fully vectorial modes of the disordered glass ber are calculated using the actual scanning electron microscope image of the ber tip. The numerical calculations show that the modes at regions closer to the boundary of the ber are more localized compared with the modes at the central regions. Coupling of an input beam to the less-localized modes with large tails at the central regions of the ber results in a large beam radius. In comparison, a beam of light launched at the regions close to the boundary couples to the highly compact modes of the ber and results in a small localized beam radius.

Formation of intermetallic compound coating on magnesium AZ91 cast alloy

NASA Astrophysics Data System (ADS)

Zhu, Tianping; Gao, Wei

2009-08-01

This study describes an intermetallic compound coating formed on AZ91 Mg cast alloy. The Al sputtered on AZ91 cast alloy reacted with substrate during a short period of heat treatment at 435°C, resulting in the formation of a continuous intermetallic compound layer. The short period treatment has the advantage of minimizing the negative effect on the microstructure of substrate and the mechanical properties, comparing with the reported diffusion coatings. DSC measurement and examination on the cross-section of Al sputtered samples show that local melting occurred along the Al/substrate interface at the temperature range between 430~435°C. The formation mechanism of intermetallic compound coating is proposed in terms of the local melting at Al/substrate interface. The salt water immersion test showed significant improvement in corrosion resistance of the intermetallic compound coated AZ91 cast alloy compared with the as-cast alloys.

Computation material science of structural-phase transformation in casting aluminium alloys

NASA Astrophysics Data System (ADS)

Golod, V. M.; Dobosh, L. Yu

2017-04-01

Successive stages of computer simulation the formation of the casting microstructure under non-equilibrium conditions of crystallization of multicomponent aluminum alloys are presented. On the basis of computer thermodynamics and heat transfer during solidification of macroscale shaped castings are specified the boundary conditions of local heat exchange at mesoscale modeling of non-equilibrium formation the solid phase and of the component redistribution between phases during coalescence of secondary dendrite branches. Computer analysis of structural - phase transitions based on the principle of additive physico-chemical effect of the alloy components in the process of diffusional - capillary morphological evolution of the dendrite structure and the o of local dendrite heterogeneity which stochastic nature and extent are revealed under metallographic study and modeling by the Monte Carlo method. The integrated computational materials science tools at researches of alloys are focused and implemented on analysis the multiple-factor system of casting processes and prediction of casting microstructure.

Dynamical localization of coupled relativistic kicked rotors

NASA Astrophysics Data System (ADS)

Rozenbaum, Efim B.; Galitski, Victor

2017-02-01

A periodically driven rotor is a prototypical model that exhibits a transition to chaos in the classical regime and dynamical localization (related to Anderson localization) in the quantum regime. In a recent work [Phys. Rev. B 94, 085120 (2016), 10.1103/PhysRevB.94.085120], A. C. Keser et al. considered a many-body generalization of coupled quantum kicked rotors, and showed that in the special integrable linear case, dynamical localization survives interactions. By analogy with many-body localization, the phenomenon was dubbed dynamical many-body localization. In the present work, we study nonintegrable models of single and coupled quantum relativistic kicked rotors (QRKRs) that bridge the gap between the conventional quadratic rotors and the integrable linear models. For a single QRKR, we supplement the recent analysis of the angular-momentum-space dynamics with a study of the spin dynamics. Our analysis of two and three coupled QRKRs along with the proved localization in the many-body linear model indicate that dynamical localization exists in few-body systems. Moreover, the relation between QRKR and linear rotor models implies that dynamical many-body localization can exist in generic, nonintegrable many-body systems. And localization can generally result from a complicated interplay between Anderson mechanism and limiting integrability, since the many-body linear model is a high-angular-momentum limit of many-body QRKRs. We also analyze the dynamics of two coupled QRKRs in the highly unusual superballistic regime and find that the resonance conditions are relaxed due to interactions. Finally, we propose experimental realizations of the QRKR model in cold atoms in optical lattices.

Decoherence-induced conductivity in the one-dimensional Anderson model

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

Stegmann, Thomas; Wolf, Dietrich E.; Ujsághy, Orsolya

We study the effect of decoherence on the electron transport in the one-dimensional Anderson model by means of a statistical model [1, 2, 3, 4, 5]. In this model decoherence bonds are randomly distributed within the system, at which the electron phase is randomized completely. Afterwards, the transport quantity of interest (e.g. resistance or conductance) is ensemble averaged over the decoherence configurations. Averaging the resistance of the sample, the calculation can be performed analytically. In the thermodynamic limit, we find a decoherence-driven transition from the quantum-coherent localized regime to the Ohmic regime at a critical decoherence density, which is determinedmore » by the second-order generalized Lyapunov exponent (GLE) [4].« less

Interpretation of high-dimensional numerical results for the Anderson transition

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

Suslov, I. M., E-mail: suslov@kapitza.ras.ru

The existence of the upper critical dimension d{sub c2} = 4 for the Anderson transition is a rigorous consequence of the Bogoliubov theorem on renormalizability of φ{sup 4} theory. For d ≥ 4 dimensions, one-parameter scaling does not hold and all existent numerical data should be reinterpreted. These data are exhausted by the results for d = 4, 5 from scaling in quasi-one-dimensional systems and the results for d = 4, 5, 6 from level statistics. All these data are compatible with the theoretical scaling dependences obtained from Vollhardt and Wolfle’s self-consistent theory of localization. The widespread viewpoint that d{submore » c2} = ∞ is critically discussed.« less

Genetic affinity between diverse ethnoreligious communities of Tamil Nadu, India: a microsatellite study.

PubMed

Eaaswarkhanth, M; Vasulu, T S; Haque, Ikramul

2008-12-01

Historically, a number of local Hindu caste groups have converted to Islam and formed religious endogamous groups. Therefore the local caste groups and religious communities in a region are expected to show genetic relatedness. In this study we investigate the genetic relationship between Tamil-speaking (Dravidian language) Muslims (Sunni), six endogamous Hindu castes, and a tribal ethnic group (Irulars) using 13 CODIS (Combined DNA Index System) autosomal microsatellite markers. Muslims show the highest average heterozygosity (0.405) compared to the other groups. The neighbor-joining tree and the multidimensional-scaling plot show clustering of Tamil-speaking Muslims with three caste groups (Gounder, Paraiyar, and Vanniyar), whereas the Irular tribe is separated out of the cluster.

Data-Driven Neural Network Model for Robust Reconstruction of Automobile Casting

NASA Astrophysics Data System (ADS)

Lin, Jinhua; Wang, Yanjie; Li, Xin; Wang, Lu

2017-09-01

In computer vision system, it is a challenging task to robustly reconstruct complex 3D geometries of automobile castings. However, 3D scanning data is usually interfered by noises, the scanning resolution is low, these effects normally lead to incomplete matching and drift phenomenon. In order to solve these problems, a data-driven local geometric learning model is proposed to achieve robust reconstruction of automobile casting. In order to relieve the interference of sensor noise and to be compatible with incomplete scanning data, a 3D convolution neural network is established to match the local geometric features of automobile casting. The proposed neural network combines the geometric feature representation with the correlation metric function to robustly match the local correspondence. We use the truncated distance field(TDF) around the key point to represent the 3D surface of casting geometry, so that the model can be directly embedded into the 3D space to learn the geometric feature representation; Finally, the training labels is automatically generated for depth learning based on the existing RGB-D reconstruction algorithm, which accesses to the same global key matching descriptor. The experimental results show that the matching accuracy of our network is 92.2% for automobile castings, the closed loop rate is about 74.0% when the matching tolerance threshold τ is 0.2. The matching descriptors performed well and retained 81.6% matching accuracy at 95% closed loop. For the sparse geometric castings with initial matching failure, the 3D matching object can be reconstructed robustly by training the key descriptors. Our method performs 3D reconstruction robustly for complex automobile castings.

Transient Gratings, Four-Wave Mixing and Polariton Effects in Nonlinear Optics

DTIC Science & Technology

1991-06-01

w, are. under some very general conditions, equal to the Fourier transform of the TG signal 1361. The possibility of exciton localization l37-3...which is tile analogue of the Anderson electron localization , could also be probed ideally by the grating technique 1401. In this review we develop a...often handled using, at mean-tield t heor ilie local -tield approximation) I 7). -lI. Our -,encral formialism reduce,, to these commnon procedureN xxci he

Publisher Correction: Anderson light localization in biological nanostructures of native silk.

PubMed

Choi, Seung Ho; Kim, Seong-Wan; Ku, Zahyun; Visbal-Onufrak, Michelle A; Kim, Seong-Ryul; Choi, Kwang-Ho; Ko, Hakseok; Choi, Wonshik; Urbas, Augustine M; Goo, Tae-Won; Kim, Young L

2018-03-19

The original PDF version of this Article contained errors in Equations 1 and 2. Both equations omitted all Γ terms. This has been corrected in the PDF version of the Article. The HTML version was correct from the time of publication.

Verification of Anderson Superexchange in MnO via Magnetic Pair Distribution Function Analysis and ab initio Theory.

PubMed

Frandsen, Benjamin A; Brunelli, Michela; Page, Katharine; Uemura, Yasutomo J; Staunton, Julie B; Billinge, Simon J L

2016-05-13

We present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ∼1  nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominated by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. The Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.

Scattering and transport statistics at the metal-insulator transition: A numerical study of the power-law banded random-matrix model

NASA Astrophysics Data System (ADS)

Méndez-Bermúdez, J. A.; Gopar, Victor A.; Varga, Imre

2010-09-01

We study numerically scattering and transport statistical properties of the one-dimensional Anderson model at the metal-insulator transition described by the power-law banded random matrix (PBRM) model at criticality. Within a scattering approach to electronic transport, we concentrate on the case of a small number of single-channel attached leads. We observe a smooth crossover from localized to delocalized behavior in the average-scattering matrix elements, the conductance probability distribution, the variance of the conductance, and the shot noise power by varying b (the effective bandwidth of the PBRM model) from small (b≪1) to large (b>1) values. We contrast our results with analytic random matrix theory predictions which are expected to be recovered in the limit b→∞ . We also compare our results for the PBRM model with those for the three-dimensional (3D) Anderson model at criticality, finding that the PBRM model with bɛ[0.2,0.4] reproduces well the scattering and transport properties of the 3D Anderson model.

Verification of Anderson superexchange in MnO via magnetic pair distribution function analysis and ab initio theory

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

Benjamin A. Frandsen; Brunelli, Michela; Page, Katharine

Here, we present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ~1 nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominatedmore » by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. Furthermore, the Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.« less

Verification of Anderson superexchange in MnO via magnetic pair distribution function analysis and ab initio theory

DOE PAGES

Benjamin A. Frandsen; Brunelli, Michela; Page, Katharine; ...

2016-05-11

Here, we present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ~1 nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominatedmore » by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. Furthermore, the Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.« less

Dual nature of localization in guiding systems with randomly corrugated boundaries: Anderson-type versus entropic

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

Tarasov, Yu.V., E-mail: yutarasov@ire.kharkov.ua; Shostenko, L.D.

A unified theory for the conductance of an infinitely long multimode quantum wire whose finite segment has randomly rough lateral boundaries is developed. It enables one to rigorously take account of all feasible mechanisms of wave scattering, both related to boundary roughness and to contacts between the wire rough section and the perfect leads within the same technical frameworks. The rough part of the conducting wire is shown to act as a mode-specific randomly modulated effective potential barrier whose height is governed essentially by the asperity slope. The mean height of the barrier, which is proportional to the average slopemore » squared, specifies the number of conducting channels. Under relatively small asperity amplitude this number can take on arbitrary small, up to zero, values if the asperities are sufficiently sharp. The consecutive channel cut-off that arises when the asperity sharpness increases can be regarded as a kind of localization, which is not related to the disorder per se but rather is of entropic or (equivalently) geometric origin. The fluctuating part of the effective barrier results in two fundamentally different types of guided wave scattering, viz., inter- and intramode scattering. The intermode scattering is shown to be for the most part very strong except in the cases of (a) extremely smooth asperities, (b) excessively small length of the corrugated segment, and (c) the asperities sharp enough for only one conducting channel to remain in the wire. Under strong intermode scattering, a new set of conducting channels develops in the corrugated waveguide, which have the form of asymptotically decoupled extended modes subject to individual solely intramode random potentials. In view of this fact, two transport regimes only are realizable in randomly corrugated multimode waveguides, specifically, the ballistic and the localized regime, the latter characteristic of one-dimensional random systems. Two kinds of localization are thus shown to coexist in waveguide-like systems with randomly corrugated boundaries, specifically, the entropic localization and the one-dimensional Anderson (disorder-driven) localization. If the particular mode propagates across the rough segment ballistically, the Fabry–Pérot-type oscillations should be observed in the conductance, which are suppressed for the mode transferred in the Anderson-localized regime.« less

Structural and compositional analysis of a casting mold sherd from ancient China.

PubMed

Zong, Yunbing; Yao, Shengkun; Lang, Jianfeng; Chen, Xuexiang; Fan, Jiadong; Sun, Zhibin; Duan, Xiulan; Li, Nannan; Fang, Hui; Zhou, Guangzhao; Xiao, Tiqiao; Li, Aiguo; Jiang, Huaidong

2017-01-01

Casting had symbolic significance and was strictly controlled in the Shang dynasty of ancient China. Vessel casting was mainly distributed around the Shang capital, Yin Ruins, which indicates a rigorous centralization of authority. Thus, for a casting mold to be excavated far from the capital region is rare. In addition to some bronze vessel molds excavated at the Buyao Village site, another key discovery of a bronze vessel mold occurred at Daxinzhuang. The Daxinzhuang site was a core area in the east of Shang state and is an important site to study the eastward expansion of the Shang. Here, combining synchrotron X-rays and other physicochemical analysis methods, nondestructive three-dimensional structure imaging and different elemental analyses were conducted on this mold sherd. Through high penetration X-ray tomography, we obtained insights on the internal structure and discovered some pores. We infer that the generation of pores inside the casting mold sherd was used to enhance air permeability during casting. Furthermore, we suppose that the decorative patterns on the surface were carved and not pasted onto it. Considering the previous compositional studies of bronze vessels, the copper and iron elements were analyzed by different methods. Unexpectedly, a larger amount of iron than of copper was detected on the surface. According to the data analysis and archaeological context, the source of iron on the casting mold sherd could be attributed to local soil contamination. A refined compositional analysis confirms that this casting mold was fabricated locally and used for bronze casting.

Generalized multiband typical medium dynamical cluster approximation: Application to (Ga,Mn)N

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

Zhang, Yi; Nelson, R.; Siddiqui, Elisha

We generalize the multiband typical medium dynamical cluster approximation and the formalism introduced by Blackman, Esterling, and Berk so that it can deal with localization in multiband disordered systems with both diagonal and off-diagonal disorder with complicated potentials. We also introduce an ansatz for the momentum-resolved typical density of states that greatly improves the numerical stability of the method while preserving the independence of scattering events at different frequencies. Starting from the first-principles effective Hamiltonian, we apply this method to the diluted magnetic semiconductor Ga 1 - x Mn x N , and find the impurity band is completely localizedmore » for Mn concentrations x < 0.03 , while for 0.03 < x < 0.10 the impurity band has delocalized states but the chemical potential resides at or above the mobility edge. So, the system is always insulating within the experimental compositional limit ( x ≈ 0.10 ) due to Anderson localization. But, for 0.03 < x < 0.10 hole doping could make the system metallic, allowing double-exchange mediated, or enhanced, ferromagnetism. Finally, this developed method is expected to have a large impact on first-principles studies of Anderson localization.« less

Generalized multiband typical medium dynamical cluster approximation: Application to (Ga,Mn)N

DOE PAGES

Zhang, Yi; Nelson, R.; Siddiqui, Elisha; ...

2016-12-29

We generalize the multiband typical medium dynamical cluster approximation and the formalism introduced by Blackman, Esterling, and Berk so that it can deal with localization in multiband disordered systems with both diagonal and off-diagonal disorder with complicated potentials. We also introduce an ansatz for the momentum-resolved typical density of states that greatly improves the numerical stability of the method while preserving the independence of scattering events at different frequencies. Starting from the first-principles effective Hamiltonian, we apply this method to the diluted magnetic semiconductor Ga 1 - x Mn x N , and find the impurity band is completely localizedmore » for Mn concentrations x < 0.03 , while for 0.03 < x < 0.10 the impurity band has delocalized states but the chemical potential resides at or above the mobility edge. So, the system is always insulating within the experimental compositional limit ( x ≈ 0.10 ) due to Anderson localization. But, for 0.03 < x < 0.10 hole doping could make the system metallic, allowing double-exchange mediated, or enhanced, ferromagnetism. Finally, this developed method is expected to have a large impact on first-principles studies of Anderson localization.« less

Entanglement entropy in a one-dimensional disordered interacting system: the role of localization.

PubMed

Berkovits, Richard

2012-04-27

The properties of the entanglement entropy (EE) in one-dimensional disordered interacting systems are studied. Anderson localization leaves a clear signature on the average EE, as it saturates on the length scale exceeding the localization length. This is verified by numerically calculating the EE for an ensemble of disordered realizations using the density matrix renormalization group method. A heuristic expression describing the dependence of the EE on the localization length, which takes into account finite-size effects, is proposed. This is used to extract the localization length as a function of the interaction strength. The localization length dependence on the interaction fits nicely with the expectations.

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

Cai Xiaoming; Chen Shu; Wang Yupeng

The superfluid-to-Anderson-insulator transition of a strongly repulsive Bose gas is studied in a one-dimensional incommensurate optical lattice. In the hard-core limit, the Bose-Fermi mapping allows us to deal with the system using the exact numerical method. Based on the Aubry-Andre model, we exploit the phase transition of the hard-core boson system from the superfluid phase with all single-particle states extended to the Bose-glass phase with all the single-particle states being Anderson localized as the strength of the incommensurate potential increases relative to the hopping amplitude. We evaluate the superfluid fraction, one-particle density matrices, momentum distributions, the natural orbitals, and theirmore » occupations. All of these quantities show that there exists a superfluid-to-insulator phase transition in the system.« less

Extent and character of early tertiary penetrative deformation, Sonora, Northwest Mexico

NASA Technical Reports Server (NTRS)

Anderson, T. H.

1985-01-01

Reconnaissance field work has led to the recognition of extensive Early Tertiary gneiss and schist which are distinguished by weakly developed to highly conspicous northeast to east-trending stretching lineation commonly accompanied by low-dipping foliation. This structural fabric has been imposed on Precambrian to Paleogene rocks. Regionally, minimum ages of deformation are based upon interpreted U-Pb isotopic ages from suites of cogenetic zircon from the Paleogene orthogneiss. Locally, the interpreted ages indicate that ductile deformation continued as late as Oligocene (Anderson and others, 1980; Silver and Anderson, 1984). The consistency of the deformational style is such that, although considerable variation in intensity exists, the fabric can be recognized and correlated in rocks away from the Paleogene orthogneiss.

Optimized Flight Path for Localization Using Line of Bearing

DTIC Science & Technology

2015-03-26

minimizing the semi-major axis of the error ellipse. (a) Thin Ellipse (area = 1000 · π) (b) Fat Ellipse (area = 1020 · π) Figure 15. Comparison of Ellipse...California, San Diego, 2012. [5] Deghat, Mohammad, Iman Shames , Brian D. O. Anderson, and Changbin Yu. “Target Localization and Circumnavigation Using...Real-Time Optimal Control for Bearing-Only Trajectory Planning”, International Journal of Micro Air Vehicles, 2014. [12] Shames , Iman, Baris Fidan

Evidence for charge-trapping inducing polymorphic structural-phase transition in pentacene.

PubMed

Ando, Masahiko; Kehoe, Tom B; Yoneya, Makoto; Ishii, Hiroyuki; Kawasaki, Masahiro; Duffy, Claudia M; Minakata, Takashi; Phillips, Richard T; Sirringhaus, Henning

2015-01-07

Trapped-charge-induced transformation of pentacene polymorphs is observed by using in situ Raman spectroscopy and molecular dynamics simulations reveal that the charge should be localized in pentacene molecules at the interface with static intermolecular disorder along the long axis. Quantum chemical calculations of the intermolecular transfer integrals suggest the disorder to be large enough to induce Anderson-type localization. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of simulated hyperemia on the flow field in a mildly atherosclerotic coronary artery casting of man

NASA Technical Reports Server (NTRS)

Cho, Y. I.; Back, L. H.; Crawford, D. W.

1985-01-01

Changes in an arterial flow field due to mild atherosclerosis were determined using a main coronary artery casting with a maximum obstruction of about 50 percent by area. Local pressure changes were measured using six pressure tap holes along the wall of the casting. The test-fluid was a 33 percent sugar-water solution of approximately the same viscosity as human blood. Flow visualization results were obtained by injecting blue-dye through the pressure tap holes. Measurement of local pressure demonstrated a significant Reynolds number effect. At Reynolds numbers of 80-710, a local pressure rise was observed downstream of the mild atherosclerotic constriction due to momentum changes. The Reynolds number necessary for flow separation in the divergent region of the coronary casting was about 330. The experimental results can be used to obtain a quantitative relation between coronary morphology and the fluid dynamic consequences of mild diffuse disease under conditions of maximum cardiac demand i.e., higher coronary flow rates and Reynolds numbers associated with space and atmospheric flight.

Structural and compositional analysis of a casting mold sherd from ancient China

PubMed Central

Zong, Yunbing; Yao, Shengkun; Lang, Jianfeng; Chen, Xuexiang; Fan, Jiadong; Sun, Zhibin; Duan, Xiulan; Li, Nannan; Fang, Hui; Zhou, Guangzhao; Xiao, Tiqiao; Li, Aiguo; Jiang, Huaidong

2017-01-01

Casting had symbolic significance and was strictly controlled in the Shang dynasty of ancient China. Vessel casting was mainly distributed around the Shang capital, Yin Ruins, which indicates a rigorous centralization of authority. Thus, for a casting mold to be excavated far from the capital region is rare. In addition to some bronze vessel molds excavated at the Buyao Village site, another key discovery of a bronze vessel mold occurred at Daxinzhuang. The Daxinzhuang site was a core area in the east of Shang state and is an important site to study the eastward expansion of the Shang. Here, combining synchrotron X-rays and other physicochemical analysis methods, nondestructive three-dimensional structure imaging and different elemental analyses were conducted on this mold sherd. Through high penetration X-ray tomography, we obtained insights on the internal structure and discovered some pores. We infer that the generation of pores inside the casting mold sherd was used to enhance air permeability during casting. Furthermore, we suppose that the decorative patterns on the surface were carved and not pasted onto it. Considering the previous compositional studies of bronze vessels, the copper and iron elements were analyzed by different methods. Unexpectedly, a larger amount of iron than of copper was detected on the surface. According to the data analysis and archaeological context, the source of iron on the casting mold sherd could be attributed to local soil contamination. A refined compositional analysis confirms that this casting mold was fabricated locally and used for bronze casting. PMID:28296963

Parallel volume ray-casting for unstructured-grid data on distributed-memory architectures

NASA Technical Reports Server (NTRS)

Ma, Kwan-Liu

1995-01-01

As computing technology continues to advance, computational modeling of scientific and engineering problems produces data of increasing complexity: large in size and unstructured in shape. Volume visualization of such data is a challenging problem. This paper proposes a distributed parallel solution that makes ray-casting volume rendering of unstructured-grid data practical. Both the data and the rendering process are distributed among processors. At each processor, ray-casting of local data is performed independent of the other processors. The global image composing processes, which require inter-processor communication, are overlapped with the local ray-casting processes to achieve maximum parallel efficiency. This algorithm differs from previous ones in four ways: it is completely distributed, less view-dependent, reasonably scalable, and flexible. Without using dynamic load balancing, test results on the Intel Paragon using from two to 128 processors show, on average, about 60% parallel efficiency.

Metal insulator transitions in perovskite SrIrO{sub 3} thin films

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

Biswas, Abhijit; Jeong, Yoon Hee, E-mail: yhj@postech.ac.kr; Kim, Ki-Seok

Understanding of metal insulator transitions in a strongly correlated system, driven by Anderson localization (disorder) and/or Mott localization (correlation), is a long standing problem in condensed matter physics. The prevailing fundamental question would be how these two mechanisms contrive to accomplish emergent anomalous behaviors. Here, we have grown high quality perovskite SrIrO{sub 3} thin films, containing a strong spin orbit coupled 5d element Ir, on various substrates such as GdScO{sub 3} (110), DyScO{sub 3} (110), SrTiO{sub 3} (001), and NdGaO{sub 3} (110) with increasing lattice mismatch, in order to carry out a systematic study on the transport properties. We foundmore » that metal insulator transitions can be induced in this system; by either reducing thickness (on best lattice matched substrate) or changing degree of lattice strain (by lattice mismatch between film and substrates) of films. Surprisingly these two pathways seek two distinct types of metal insulator transitions; the former falls into disorder driven Anderson type whereas the latter turns out to be of unconventional Mott-Anderson type with the interplay of disorder and correlation. More interestingly, in the metallic phases of SrIrO{sub 3}, unusual non-Fermi liquid characteristics emerge in resistivity as Δρ ∝ T{sup ε} with ε evolving from 4/5 to 1 to 3/2 with increasing lattice strain. We discuss theoretical implications of these phenomena to shed light on the metal insulator transitions.« less

Phase Diagrams of Three-Dimensional Anderson and Quantum Percolation Models Using Deep Three-Dimensional Convolutional Neural Network

NASA Astrophysics Data System (ADS)

Mano, Tomohiro; Ohtsuki, Tomi

2017-11-01

The three-dimensional Anderson model is a well-studied model of disordered electron systems that shows the delocalization-localization transition. As in our previous papers on two- and three-dimensional (2D, 3D) quantum phase transitions [J. Phys. Soc. Jpn. 85, 123706 (2016), 86, 044708 (2017)], we used an image recognition algorithm based on a multilayered convolutional neural network. However, in contrast to previous papers in which 2D image recognition was used, we applied 3D image recognition to analyze entire 3D wave functions. We show that a full phase diagram of the disorder-energy plane is obtained once the 3D convolutional neural network has been trained at the band center. We further demonstrate that the full phase diagram for 3D quantum bond and site percolations can be drawn by training the 3D Anderson model at the band center.

Disordered Kitaev chains with long-range pairing.

PubMed

Cai, Xiaoming

2017-03-22

We study the competition of disorder and superconductivity for a generalized Kitaev model in incommensurate potentials. The generalized Kitaev model describes one dimensional spinless fermions with long-range p-wave superconducting pairing, which decays with distance l as a power law  ∼[Formula: see text]. We focus on the transition from the topological superconducting phase to the topologically trivial Anderson localized phase, and effects of the exponent α on this phase transition. In the topological superconducting phase, for a system under open boundary condition the amplitude of zero-mode Majorana fermion has a hybrid exponential-algebraic decay as the distance increases from the edge. In the Anderson localized phase, some single-particle states remain critical for very strong disorders and the number of critical states increases as α decreases. In addition, except for critical disorders, the correlation function always has an exponential decay at the short range and an algebraic decay at the long range. Phase transition points are also numerically determined and the topological phase transition happens earlier at a smaller disorder strength for a system with smaller α.

Field testing of jet-grouted pile : [summary].

DOT National Transportation Integrated Search

2014-01-01

In many areas of Florida, local geology dictates the use of deep foundations for transportation structures bridges, noise walls, signage, etc. When concrete piles are used, they are either prestressed at the casting yard, cast in situ through a h...

Management of Gustilo Anderson III B open tibial fractures by primary fascio-septo-cutaneous local flap and primary fixation: The 'fix and shift' technique.

PubMed

Ramasamy, P R

2017-01-01

Open fractures of tibia have posed great difficulty in managing both the soft tissue and the skeletal components of the injured limb. Gustilo Anderson III B open tibial fractures are more difficult to manage than I, II, and III A fractures. Stable skeletal fixation with immediate soft tissue cover has been the key to the successful outcome in treating open tibial fractures, in particular, Gustilo Anderson III B types. If the length of the open wound is larger and if the exposed surface of tibial fracture and tibial shaft is greater, then the management becomes still more difficult. Thirty six Gustilo Anderson III B open tibial fractures managed between June 2002 and December 2013 with "fix and shift" technique were retrospectively reviewed. All the 36 patients managed by this technique had open wounds measuring >5 cm (post debridement). Under fix and shift technique, stable fixation involved primary external fixator application or primary intramedullary nailing of the tibial fracture and immediate soft tissue cover involved septocutaneous shift, i.e., shifting of fasciocutaneous segments based on septocutaneous perforators. Primary fracture union rate was 50% and reoperation rate (bone stimulating procedures) was 50%. Overall fracture union rate was 100%. The rate of malunion was 14% and deep infection was 16%. Failure of septocutaneous shift was 2.7%. There was no incidence of amputation. Management of Gustilo Anderson III B open tibial fractures with "fix and shift" technique has resulted in better outcome in terms of skeletal factors (primary fracture union, overall union, and time for union and malunion) and soft tissue factors (wound healing, flap failure, access to secondary procedures, and esthetic appearance) when compared to standard methods adopted earlier. Hence, "fix and shift" could be recommended as one of the treatment modalities for open III B tibial fractures.

Out-of-equilibrium dynamics of repulsive Fermi gases in quasiperiodic potentials: A density functional theory study

NASA Astrophysics Data System (ADS)

Ancilotto, Francesco; Rossini, Davide; Pilati, Sebastiano

2018-04-01

The dynamics of a one-dimensional two-component Fermi gas in the presence of a quasiperiodic optical lattice (OL) is investigated by means of a density functional theory approach. Inspired by the protocol implemented in recent cold-atom experiments—designed to identify the many-body localization transition—we analyze the relaxation of an initially prepared imbalance between the occupation number of odd and of even sites. For quasidisorder strength beyond the Anderson localization transition, the imbalance survives for long times, indicating the inability of the system to reach local equilibrium. The late-time value of the imbalance diminishes for increasing interaction strength. Close to the critical quasidisorder strength corresponding to the noninteracting (Anderson) transition, the interacting system displays an extremely slow relaxation dynamics, consistent with subdiffusive behavior. The amplitude of the imbalance fluctuations around its running average is found to decrease with time, and such damping is more effective with increasing interaction strengths. While our study addresses the setup with two equally intense OLs, very similar effects due to interactions have been observed also in recent cold-atom experiments performed in the tight-binding regime, i.e., where one of the two OLs is very deep and the other is much weaker.

Calibration of the local magnitude scale ( M L ) for Peru

NASA Astrophysics Data System (ADS)

Condori, Cristobal; Tavera, Hernando; Marotta, Giuliano Sant'Anna; Rocha, Marcelo Peres; França, George Sand

2017-07-01

We propose a local magnitude scale ( M L ) for Peru, based on the original Richter definition, using 210 seismic events between 2011 and 2014, recorded by 35 broadband stations of the National Seismic Network operated by the Geophysical Institute of Peru. In the solution model, we considered 1057 traces of maximum amplitude records on the vertical channel from simulated Wood-Anderson seismograms of shallow events (depths between 0 and 60 km) and hypocentral distances less than 600 km. The attenuation factor has been evaluated in terms of geometrical spreading and anelastic attenuation coefficients. The magnitude M L was defined as M L = L o g 10 A W A +1.5855 L o g 10( R/100)+0.0008( R-100)+3± S, where, A W A is the displacement amplitude in millimeters (Wood-Anderson), R is the hypocentral distance (km), and S is the station correction. The results obtained for M L have good correlation with the m b , M s and M w values reported the ISC and NEIC. The anelastic attenuation curve obtained has a similar behavior to that other highly seismic regions. Station corrections were determined for all stations during the regression analysis resulting in values ranging between -0.97 and +0.73, suggesting a strong influence of local site effects on amplitude.

Analytical description of the transverse Anderson localization of light

NASA Astrophysics Data System (ADS)

Schirmacher, Walter; Leonetti, Marco; Ruocco, Giancarlo

2017-04-01

We develop an analytical theory for describing the transverse localization properties of light beams in optical fibers with lateral disorder. This theory, which starts from the widely used paraxial approximation for the Helmholtz equation of the electric field, is a combination of an effective-medium theory for transverse disorder with the self-consistent localization theory of Vollhardt and Wölfle. We obtain explicit expressions for the dependence of the transverse localization length on the direction along the fiber. These results are in agreement with simulational data published recently by Karbasi et al. In particular we explain the focussing mechanism leading to the establishment of narrow transparent channels along the sample.

Commensurability effects in one-dimensional Anderson localization: Anomalies in eigenfunction statistics

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

Kravtsov, V.E., E-mail: kravtsov@ictp.it; Landau Institute for Theoretical Physics, 2 Kosygina st., 117940 Moscow; Yudson, V.I., E-mail: yudson@isan.troitsk.ru

Highlights: > Statistics of normalized eigenfunctions in one-dimensional Anderson localization at E = 0 is studied. > Moments of inverse participation ratio are calculated. > Equation for generating function is derived at E = 0. > An exact solution for generating function at E = 0 is obtained. > Relation of the generating function to the phase distribution function is established. - Abstract: The one-dimensional (1d) Anderson model (AM), i.e. a tight-binding chain with random uncorrelated on-site energies, has statistical anomalies at any rational point f=(2a)/({lambda}{sub E}) , where a is the lattice constant and {lambda}{sub E} is the demore » Broglie wavelength. We develop a regular approach to anomalous statistics of normalized eigenfunctions {psi}(r) at such commensurability points. The approach is based on an exact integral transfer-matrix equation for a generating function {Phi}{sub r}(u, {phi}) (u and {phi} have a meaning of the squared amplitude and phase of eigenfunctions, r is the position of the observation point). This generating function can be used to compute local statistics of eigenfunctions of 1d AM at any disorder and to address the problem of higher-order anomalies at f=p/q with q > 2. The descender of the generating function P{sub r}({phi}){identical_to}{Phi}{sub r}(u=0,{phi}) is shown to be the distribution function of phase which determines the Lyapunov exponent and the local density of states. In the leading order in the small disorder we derived a second-order partial differential equation for the r-independent ('zero-mode') component {Phi}(u, {phi}) at the E = 0 (f=1/2 ) anomaly. This equation is nonseparable in variables u and {phi}. Yet, we show that due to a hidden symmetry, it is integrable and we construct an exact solution for {Phi}(u, {phi}) explicitly in quadratures. Using this solution we computed moments I{sub m} = N< vertical bar {psi} vertical bar {sup 2m}> (m {>=} 1) for a chain of the length N {yields} {infinity} and found an essential difference between their m-behavior in the center-of-band anomaly and for energies outside this anomaly. Outside the anomaly the 'extrinsic' localization length defined from the Lyapunov exponent coincides with that defined from the inverse participation ratio ('intrinsic' localization length). This is not the case at the E = 0 anomaly where the extrinsic localization length is smaller than the intrinsic one. At E = 0 one also observes an anomalous enhancement of large moments compatible with existence of yet another, much smaller characteristic length scale.« less

Adaptive significance of the Indian caste system: an ecological perspective.

PubMed

Gadgil, M; Malhotra, K C

1983-01-01

Indian society is an agglomeration of several thousand endogamous groups or castes each with a restricted geographical range and a hereditarily determined mode of subsistence. These reproductively isolated castes may be compared to biological species, and the society thought of as a biological community with each caste having its specific ecological niche. In this paper we examine the ecological-niche relationships of castes which are directly dependent on natural resources. Evidence is presented to show that castes living together in the same region had so organized their pattern of resource use as to avoid excessive intercaste competition for limiting resources. Furthermore, territorial division of the total range of the caste regulated intra-caste competition. Hence, a particular plant or animal resource in a given locality was used almost exclusively by a given lineage within a caste generation after generation. This favoured the cultural evolution of traditions ensuring sustainable use of natural resources. This must have contributed significantly to the stability of Indian caste society over several thousand years. The collapse of the base of natural resources and increasing monetarization of the economy has, however, destroyed the earlier complementarity between the different castes and led to increasing conflicts between them in recent years.

Three solutions to a single problem: alternative casting frames for treating infantile idiopathic scoliosis.

PubMed

Halanski, Matthew A; Harper, Benjamin L; Cassidy, Jeffry A; Crawford, Haemish A

2013-07-01

This is a technique article discussing 3 alternative frames for casting children with infantile scoliosis. To provide surgeons with alternatives to expensive specialized casting tables to allow local treatment of these children utilizing readily available materials present at most institutions. Casting for infantile scoliosis has become more popular as reports have shown promising results with this technique without the morbidity and complications associated with more invasive procedures. However, without a specialized casting table, treating these patients has been limited to a few centers throughout the country often causing patients to travel large distances to receive care. Three different alternatives to commercially available casting frames are presented. Requirements, setup, and techniques are discussed. Each surgeon has had success with each of these frames. These provide adequate support and traction while allowing enough access to the trunk to apply a well-molded cast. Cotrel/Metha casting for infantile scoliosis can be accomplished without a specialized table using commonly available equipment.

Templates Aid Removal Of Defects From Castings

NASA Technical Reports Server (NTRS)

Hendrickson, Robert G.

1992-01-01

Templates used to correlate defects in castings with local wall thicknesses. Placed on part to be inspected after coated with penetrant dye. Positions of colored spots (indicative of defects) noted. Ultrasonic inspector measures thickness of wall at unacceptable defects only - overall inspection not necessary.

Anderson acceleration and application to the three-temperature energy equations

NASA Astrophysics Data System (ADS)

An, Hengbin; Jia, Xiaowei; Walker, Homer F.

2017-10-01

The Anderson acceleration method is an algorithm for accelerating the convergence of fixed-point iterations, including the Picard method. Anderson acceleration was first proposed in 1965 and, for some years, has been used successfully to accelerate the convergence of self-consistent field iterations in electronic-structure computations. Recently, the method has attracted growing attention in other application areas and among numerical analysts. Compared with a Newton-like method, an advantage of Anderson acceleration is that there is no need to form the Jacobian matrix. Thus the method is easy to implement. In this paper, an Anderson-accelerated Picard method is employed to solve the three-temperature energy equations, which are a type of strong nonlinear radiation-diffusion equations. Two strategies are used to improve the robustness of the Anderson acceleration method. One strategy is to adjust the iterates when necessary to satisfy the physical constraint. Another strategy is to monitor and, if necessary, reduce the matrix condition number of the least-squares problem in the Anderson-acceleration implementation so that numerical stability can be guaranteed. Numerical results show that the Anderson-accelerated Picard method can solve the three-temperature energy equations efficiently. Compared with the Picard method without acceleration, Anderson acceleration can reduce the number of iterations by at least half. A comparison between a Jacobian-free Newton-Krylov method, the Picard method, and the Anderson-accelerated Picard method is conducted in this paper.

Anderson localization and ''universal'' degradation of T/sub c/ in high-temperature superconductors

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

Leavens, C.R.

Anderson, Muttalib, and Ramakrishnan (AMR) showed that strong disorder leads to a frequency (..omega..) dependent increase of the Coulomb repulsion in a three-dimensional superconductor. Their one-free-parameter theory agrees nicely with the experimentally observed decrease in T/sub c/ but only for a fitted critical resistivity (rho/sub c/) that is very much smaller than the free-electron-gas estimate (rho/sup f//sub c/). We reexamine the effect of AMR's disorder-enhanced Coulomb repulsion using the Eliashberg equations for T/sub c/ rather than the simple two-square-well aproximation to them which is suspect when there are more than two characteristic frequencies involved. The most important modification of themore » original calculation is the inclusion of the Coulomb contribution to the renormalization function Z(..omega..).« less

Universal Knight shift anomaly in the periodic Anderson model

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

Jiang, M.; Curro, N. J.; Scalettar, R. T.

Here, we report a Determinant Quantum Monte Carlo investigation which quantifies the behavior of the susceptibility and the entropy in the framework of the periodic Anderson model (PAM), focussing on the evolution with different degree of conduction electron (c) -local moment (f) hybridization. These results capture the behavior observed in several experiments, including the universal behavior of the NMR Knight shift anomaly below the crossover temperature, T*. We find that T* is a measure of the onset of c-f correlations and grows with increasing hybridization. Our results suggest that the NMR Knight shift and spin-lattice relaxation rate measurements in non-Fermimore » liquid materials are strongly influenced by temperature-dependent hybridization processes. Furthermore, our results provide a microscopic basis for the phenomenological two-fluid model of Kondo lattice behavior, and its evolution with pressure and temperature.« less

Non-Fermi Liquid Behavior and Continuously Tunable Resistivity Exponents in the Anderson-Hubbard Model at Finite Temperature

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

Patel, Niravkumar D.; Mukherjee, Anamitra; Kaushal, Nitin

Here, we employ a recently developed computational many-body technique to study for the first time the half-filled Anderson-Hubbard model at finite temperature and arbitrary correlation U and disorder V strengths. Interestingly, the narrow zero temperature metallic range induced by disorder from the Mott insulator expands with increasing temperature in a manner resembling a quantum critical point. Our study of the resistivity temperature scaling T α for this metal reveals non-Fermi liquid characteristics. Moreover, a continuous dependence of α on U and V from linear to nearly quadratic is observed. We argue that these exotic results arise from a systematic changemore » with U and V of the “effective” disorder, a combination of quenched disorder and intrinsic localized spins.« less

75 FR 34170 - Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-16

... Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC, Troy, MI... the Anderson, South Carolina location of Plastic Omnium Automotive Exteriors, LLC, working out of Troy... certification to include workers in support of the Anderson, South Carolina facility working out of Troy...

Temperature Dependence of the Upper Critical Field in Disordered Hubbard Model with Attraction

NASA Astrophysics Data System (ADS)

Kuchinskii, E. Z.; Kuleeva, N. A.; Sadovskii, M. V.

2017-12-01

We study disorder effects upon the temperature behavior of the upper critical magnetic field in an attractive Hubbard model within the generalized DMFT+Σ approach. We consider the wide range of attraction potentials U—from the weak coupling limit, where superconductivity is described by BCS model, up to the strong coupling limit, where superconducting transition is related to Bose-Einstein condensation (BEC) of compact Cooper pairs, formed at temperatures significantly higher than superconducting transition temperature, as well as the wide range of disorder—from weak to strong, when the system is in the vicinity of Anderson transition. The growth of coupling strength leads to the rapid growth of H c2( T), especially at low temperatures. In BEC limit and in the region of BCS-BEC crossover H c2( T), dependence becomes practically linear. Disordering also leads to the general growth of H c2( T). In BCS limit of weak coupling increasing disorder lead both to the growth of the slope of the upper critical field in the vicinity of the transition point and to the increase of H c2( T) in the low temperature region. In the limit of strong disorder in the vicinity of the Anderson transition localization corrections lead to the additional growth of H c2( T) at low temperatures, so that the H c2( T) dependence becomes concave. In BCS-BEC crossover region and in BEC limit disorder only slightly influences the slope of the upper critical field close to T c . However, in the low temperature region H c2 ( T may significantly grow with disorder in the vicinity of the Anderson transition, where localization corrections notably increase H c2 ( T = 0) also making H c2( T) dependence concave.

Experimental Observation of Dynamical Localization in Laser-Kicked Molecular Rotors.

PubMed

Bitter, M; Milner, V

2016-09-30

The periodically kicked rotor is a paradigm system for studying quantum effects on classically chaotic dynamics. The wave function of the quantum rotor localizes in angular momentum space, similarly to Anderson localization of the electronic wave function in disordered solids. Here, we observe dynamical localization in a system of true quantum rotors by subjecting nitrogen molecules to periodic sequences of femtosecond pulses. Exponential distribution of the molecular angular momentum-the hallmark of dynamical localization-is measured directly by means of coherent Raman scattering. We demonstrate the suppressed rotational energy growth with the number of laser kicks and study the dependence of the localization length on the kick strength. Because of its quantum coherent nature, both timing and amplitude noise are shown to destroy the localization and revive the diffusive growth of energy.

A taxonomic monograph of the leaf-litter inhabiting weevil genus Plumolepilius new genus (Coleoptera: Curculionidae: Molytinae: Conotrachelini) from Mexico, Guatemala, and El Salvador.

PubMed

Barrios-Izás, Manuel A; Anderson, Robert S; Morrone, Juan J

2016-09-14

We describe the Mesoamerican leaf litter weevil genus Plumolepilius Barrios-Izás & Anderson, new genus (Coleoptera: Curculionidae: Molytinae: Conotrachelini) (type species P. trifiniensis Barrios-Izás & Anderson, new species), species of which inhabit mountain ecosystems from the state of Chiapas in southeastern Mexico to northern Panama. In this paper we describe nine new species from Mexico, Guatemala, and El Salvador: P. trifiniensis Barrios-Izás & Anderson, new species (El Salvador and Guatemala); P. branstetteri Barrios-Izás & Anderson, new species (Guatemala and Mexico); P. longinoi Barrios-Izás & Anderson, new species (Guatemala and Mexico); P. cortezi Barrios-Izás & Anderson, new species (Guatemala and Mexico); P. canoi Barrios-Izás & Anderson, new species (Guatemala); P. schusteri Barrios-Izás & Anderson, new species (Guatemala and Mexico); P. daryi Barrios-Izás & Anderson, new species (Guatemala); P. yolnabajensis Barrios-Izás & Anderson, new species (Guatemala); and P. macalajauensis Barrios-Izás & Anderson, new species (Guatemala).        The genus and the species are named and described, information on their geographical distributions is given and images of the habitus of both sexes and the aedeagus are presented. A key to the species of Plumolepilius based on males is included.        The monophyly of Plumolepilius was confirmed by a parsimony analysis of external and male aedeagus morphology and the genus is best characterized by the presence of plumose scales lining the prosternal channel. Phylogenetic analysis supports that Lepilius Champion 1905 is the sister genus of Plumolepilius.

Position-dependent radiative transfer as a tool for studying Anderson localization: Delay time, time-reversal and coherent backscattering

NASA Astrophysics Data System (ADS)

van Tiggelen, B. A.; Skipetrov, S. E.; Page, J. H.

2017-05-01

Previous work has established that the localized regime of wave transport in open media is characterized by a position-dependent diffusion coefficient. In this work we study how the concept of position-dependent diffusion affects the delay time, the transverse confinement, the coherent backscattering, and the time reversal of waves. Definitions of energy transport velocity of localized waves are proposed. We start with a phenomenological model of radiative transfer and then present a novel perturbational approach based on the self-consistent theory of localization. The latter allows us to obtain results relevant for realistic experiments in disordered quasi-1D wave guides and 3D slabs.

Anderson Localization for Schrödinger Operators on with Strongly Mixing Potentials

NASA Astrophysics Data System (ADS)

Bourgain, Jean; Schlag, Wilhelm

In this paper we show that for a.e. x∈[ 0,2 π) the operators defined on as and with Dirichlet condition ψ- 1= 0, have pure point spectrum in with exponentially decaying eigenfunctions where δ > 0 and are small. As it is a simple consequence of known techniques that for small λ one has [- 2 +δ, 2-δ]⊂ spectrum (H(x)) for a.e.x∈[ 0, 2 π), we thus established Anderson localization on the spectrum up to the edges and the center. More general potentials than cosine can be treated, but only those energies with nonzero spectral density are allowed. Finally, we prove the same result for operators on the whole line with potential , where A:?2-->?2 is a hyperbolic toral automorphism, F∈C1(?2), ∫F= 0, and λ small. The basis for our analysis is an asymptotic formula for the Lyapunov exponent for λ--> 0 by Figotin-Pastur, and generalized by Chulaevski-Spencer. We combine this asymptotic expansion with certain martingale large deviation estimates in order to apply the methods developed by Bourgain and Goldstein in the quasi-periodic case.

Anderson localization on the Cayley tree: multifractal statistics of the transmission at criticality and off criticality

NASA Astrophysics Data System (ADS)

Monthus, Cécile; Garel, Thomas

2011-04-01

In contrast to finite dimensions where disordered systems display multifractal statistics only at criticality, the tree geometry induces multifractal statistics for disordered systems also off criticality. For the Anderson tight-binding localization model defined on a tree of branching ratio K = 2 with N generations, we consider the Miller-Derrida scattering geometry (1994 J. Stat. Phys. 75 357), where an incoming wire is attached to the root of the tree, and where KN outcoming wires are attached to the leaves of the tree. In terms of the KN transmission amplitudes tj, the total Landauer transmission is T ≡ ∑j|tj|2, so that each channel j is characterized by the weight wj = |tj|2/T. We numerically measure the typical multifractal singularity spectrum f(α) of these weights as a function of the disorder strength W and we obtain the following conclusions for its left termination point α+(W). In the delocalized phase W < Wc, α+(W) is strictly positive α+(W) > 0 and is associated with a moment index q+(W) > 1. At criticality, it vanishes α+(Wc) = 0 and is associated with the moment index q+(Wc) = 1. In the localized phase W > Wc, α+(W) = 0 is associated with some moment index q+(W) < 1. We discuss the similarities with the exact results concerning the multifractal properties of the directed polymer on the Cayley tree.

Experimental Observation of Dynamical Localization in Laser-Kicked Molecular Rotors

NASA Astrophysics Data System (ADS)

Bitter, M.; Milner, V.

2016-09-01

The periodically kicked rotor is a paradigm system for studying quantum effects on classically chaotic dynamics. The wave function of the quantum rotor localizes in angular momentum space, similarly to Anderson localization of the electronic wave function in disordered solids. Here, we observe dynamical localization in a system of true quantum rotors by subjecting nitrogen molecules to periodic sequences of femtosecond pulses. Exponential distribution of the molecular angular momentum—the hallmark of dynamical localization—is measured directly by means of coherent Raman scattering. We demonstrate the suppressed rotational energy growth with the number of laser kicks and study the dependence of the localization length on the kick strength. Because of its quantum coherent nature, both timing and amplitude noise are shown to destroy the localization and revive the diffusive growth of energy.

Independent origins of Indian caste and tribal paternal lineages.

PubMed

Cordaux, Richard; Aunger, Robert; Bentley, Gillian; Nasidze, Ivane; Sirajuddin, S M; Stoneking, Mark

2004-02-03

The origins of the nearly one billion people inhabiting the Indian subcontinent and following the customs of the Hindu caste system are controversial: are they largely derived from Indian local populations (i.e. tribal groups) or from recent immigrants to India? Archaeological and linguistic evidence support the latter hypothesis, whereas recent genetic data seem to favor the former hypothesis. Here, we analyze the most extensive dataset of Indian caste and tribal Y chromosomes to date. We find that caste and tribal groups differ significantly in their haplogroup frequency distributions; caste groups are homogeneous for Y chromosome variation and more closely related to each other and to central Asian groups than to Indian tribal or any other Eurasian groups. We conclude that paternal lineages of Indian caste groups are primarily descended from Indo-European speakers who migrated from central Asia approximately 3,500 years ago. Conversely, paternal lineages of tribal groups are predominantly derived from the original Indian gene pool. We also provide evidence for bidirectional male gene flow between caste and tribal groups. In comparison, caste and tribal groups are homogeneous with respect to mitochondrial DNA variation, which may reflect the sociocultural characteristics of the Indian caste society.

Correlation effects in superconducting quantum dot systems

NASA Astrophysics Data System (ADS)

Pokorný, Vladislav; Žonda, Martin

2018-05-01

We study the effect of electron correlations on a system consisting of a single-level quantum dot with local Coulomb interaction attached to two superconducting leads. We use the single-impurity Anderson model with BCS superconducting baths to study the interplay between the proximity induced electron pairing and the local Coulomb interaction. We show how to solve the model using the continuous-time hybridization-expansion quantum Monte Carlo method. The results obtained for experimentally relevant parameters are compared with results of self-consistent second order perturbation theory as well as with the numerical renormalization group method.

Two-dimensional conductors with interactions and disorder from particle-vortex duality

NASA Astrophysics Data System (ADS)

Goldman, H.; Mulligan, M.; Raghu, S.; Torroba, G.; Zimet, M.

2017-12-01

We study Dirac fermions in two spatial dimensions (2D) coupled to strongly fluctuating U (1 ) gauge fields in the presence of quenched disorder. Such systems are dual to theories of free Dirac fermions, which are vortices of the original theory. In analogy to superconductivity, when these fermionic vortices localize, the original system becomes a perfect conductor, and when the vortices possess a finite conductivity, the original fermions do as well. We provide several realizations of this principle and thereby introduce examples of strongly interacting 2D metals that evade Anderson localization.

Localization and hopping conduction in glass and crystal phases of monatomic Au layers on a silicon surface

NASA Astrophysics Data System (ADS)

Yamazaki, Shiro; Matsuda, Iwao; Okino, Hiroyuki; Morikawa, Harumo; Hasegawa, Shuji

2009-02-01

Monatomic layers of Au on Si(111) exhibit a glass-crystal phase transition between the ordered crystalline 6×6 reconstruction and the disordered glassy β-3×3 reconstruction on thermal annealing. Micro-four-point-probe electrical conductivity measurements clearly revealed that both monatomic layers had conductivities as large as the minimum metallic conductivity at the low-temperature region (˜10-100K) , and were well described by transport theory regarding Anderson localization. The sheet conductivity of the 6×6 was higher than that of the β-3×3 , which was attributed to different degrees of carrier localization.

Effect of Anharmonicity on the Kondo Phenomena of a Magnetic Ion Vibrating in a Confinement Potential

NASA Astrophysics Data System (ADS)

Yashiki, Satoshi; Ueda, Kazuo

2011-08-01

Effect of anharmonicity of a cage potential for a magnetic ion vibrating in a metal is investigated by the numerical renormalization group method. The cage potential is assumed to be one-dimensional and of the double-well type. In the absence of the Coulomb interaction, we find continuous crossover among the three limiting cases: Yu--Anderson-type Kondo regime, the double-well-type Kondo one, and the renormalized Fermi chain one. In the entire parameter space of the double-well potential, the ground state is described by a local Fermi liquid. In the Yu--Anderson-type Kondo regime, a quantum phase transition to the ground state with odd parity takes place passing through the two-channel Kondo fixed point when the Coulomb interaction increases. Therefore, the vibration of a magnetic ion in an oversized cage structure is a promising route to the two-channel Kondo effect.

Interview with Philip W. Anderson

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

Anderson, P.W.

1988-08-01

Phil Anderson, Professor of Physics at Princeton University, has devoted his career to research in theoretical physics. He is a member of the National Academy of Science and the American Academy of Arts and Sciences, a foreign member of the Royal Society, and a foreign associate of the Accademia Lincei in Rome. The Americal Physical Society awarded him the Oliver E. Buckley Solid State Physics Prize in 1964. In 1977 he won the Nobel Prize in Physics with J.H. van Vleck and N.F. Mott. His work has encompassed a broad range of subjects: quantum theory of condensed matter, broken symmetry,more » transport theory and localization, random statistical systems, spectral line broadening, superfluidity in helium and neutron stars, magnetism, and superconductivity. His avocations include ''hiking, the game of GO, Romanesque architecture, and the human condition.'' In this interview he explains his RVB theory of the oxide superconductors and its historical context.« less

Chromospheric heating by acoustic shock waves

NASA Technical Reports Server (NTRS)

Jordan, Stuart D.

1993-01-01

Work by Anderson & Athay (1989) suggests that the mechanical energy required to heat the quiet solar chromosphere might be due to the dissipation of weak acoustic shocks. The calculations reported here demonstrate that a simple picture of chromospheric shock heating by acoustic waves propagating upward through a model solar atmosphere, free of both magnetic fields and local inhomogeneities, cannot reproduce their chromospheric model. The primary reason is the tendency for vertically propagating acoustic waves in the range of allowed periods to dissipate too low in the atmosphere, providing insufficient residual energy for the middle chromosphere. The effect of diverging magnetic fields and the corresponding expanding acoustic wavefronts on the mechanical dissipation length is then discussed as a means of preserving a quasi-acoustic heating hypothesis. It is argued that this effect, in a canopy that overlies the low chromosphere, might preserve the acoustic shock hypothesis consistent with the chromospheric radiation losses computed by Anderson & Athay.

Genetic variation in South Indian castes: evidence from Y-chromosome, mitochondrial, and autosomal polymorphisms

PubMed Central

Watkins, WS; Thara, R; Mowry, BJ; Zhang, Y; Witherspoon, DJ; Tolpinrud, W; Bamshad, MJ; Tirupati, S; Padmavati, R; Smith, H; Nancarrow, D; Filippich, C; Jorde, LB

2008-01-01

Background Major population movements, social structure, and caste endogamy have influenced the genetic structure of Indian populations. An understanding of these influences is increasingly important as gene mapping and case-control studies are initiated in South Indian populations. Results We report new data on 155 individuals from four Tamil caste populations of South India and perform comparative analyses with caste populations from the neighboring state of Andhra Pradesh. Genetic differentiation among Tamil castes is low (RST = 0.96% for 45 autosomal short tandem repeat (STR) markers), reflecting a largely common origin. Nonetheless, caste- and continent-specific patterns are evident. For 32 lineage-defining Y-chromosome SNPs, Tamil castes show higher affinity to Europeans than to eastern Asians, and genetic distance estimates to the Europeans are ordered by caste rank. For 32 lineage-defining mitochondrial SNPs and hypervariable sequence (HVS) 1, Tamil castes have higher affinity to eastern Asians than to Europeans. For 45 autosomal STRs, upper and middle rank castes show higher affinity to Europeans than do lower rank castes from either Tamil Nadu or Andhra Pradesh. Local between-caste variation (Tamil Nadu RST = 0.96%, Andhra Pradesh RST = 0.77%) exceeds the estimate of variation between these geographically separated groups (RST = 0.12%). Low, but statistically significant, correlations between caste rank distance and genetic distance are demonstrated for Tamil castes using Y-chromosome, mtDNA, and autosomal data. Conclusion Genetic data from Y-chromosome, mtDNA, and autosomal STRs are in accord with historical accounts of northwest to southeast population movements in India. The influence of ancient and historical population movements and caste social structure can be detected and replicated in South Indian caste populations from two different geographic regions. PMID:19077280

Phase-field simulation of microstructure formation in technical castings - A self-consistent homoenthalpic approach to the micro-macro problem

NASA Astrophysics Data System (ADS)

Böttger, B.; Eiken, J.; Apel, M.

2009-10-01

Performing microstructure simulation of technical casting processes suffers from the strong interdependency between latent heat release due to local microstructure formation and heat diffusion on the macroscopic scale: local microstructure formation depends on the macroscopic heat fluxes and, in turn, the macroscopic temperature solution depends on the latent heat release, and therefore on the microstructure formation, in all parts of the casting. A self-consistent homoenthalpic approximation to this micro-macro problem is proposed, based on the assumption of a common enthalpy-temperature relation for the whole casting which is used for the description of latent heat production on the macroscale. This enthalpy-temperature relation is iteratively obtained by phase-field simulations on the microscale, thus taking into account the specific morphological impact on the latent heat production. This new approach is discussed and compared to other approximations for the coupling of the macroscopic heat flux to complex microstructure models. Simulations are performed for the binary alloy Al-3at%Cu, using a multiphase-field solidification model which is coupled to a thermodynamic database. Microstructure formation is simulated for several positions in a simple model plate casting, using a one-dimensional macroscopic temperature solver which can be directly coupled to the microscopic phase-field simulation tool.

Modeling the surface contamination of dental titanium investment castings.

PubMed

Atwood, R C; Lee, P D; Curtis, R V

2005-02-01

The objective of this study was to develop a computational tool for assisting the design of titanium dental castings with minimal defects and to compare computational simulations with casting experiments. Modeling. An in-house cellular-automata solidification and finite-difference diffusion program was coupled with a commercial casting program and applied to (a) simple geometric wedge models and (b) a 3D-laser scan of a molar crown casting. Experimental. Wedges and molar crowns were hand-waxed and investment cast in commercial purity grade 1 (CP-1) titanium by a commercial dental laboratory. The castings were sectioned and analyzed using light and scanning electron microscopy, X-ray microanalysis, and microhardness testing. In the wedge sample, contamination with impurities (Al, Si), including intermetallic precipitates, was found to extend to a depth ranging from 30 to 120 microm depending on the section thickness and hence the local cooling rate. Microstructural and mechanical (hardness) effects were found to a depth ranging from 80 to 250 microm. The coupled micro/macro model predictions showed reasonable agreement for the pattern of contamination. Dental and medical applications demand close dimensional tolerance and freedom from surface impurities and structural flaws in castings having unique shapes. The ability to predict the structural, mechanical, and chemical changes resulting from the casting process will help to design the casting and post-casting processes to minimize these problems.

Indigenous lunar construction materials

NASA Technical Reports Server (NTRS)

Rogers, Wayne; Sture, Stein

1991-01-01

The objectives are the following: to investigate the feasibility of the use of local lunar resources for construction of a lunar base structure; to develop a material processing method and integrate the method with design and construction of a pressurized habitation structure; to estimate specifications of the support equipment necessary for material processing and construction; and to provide parameters for systems models of lunar base constructions, supply, and operations. The topics are presented in viewgraph form and include the following: comparison of various lunar structures; guidelines for material processing methods; cast lunar regolith; examples of cast basalt components; cast regolith process; processing equipment; mechanical properties of cast basalt; material properties and structural design; and future work.

Thermoelectricity near Anderson localization transitions

NASA Astrophysics Data System (ADS)

Yamamoto, Kaoru; Aharony, Amnon; Entin-Wohlman, Ora; Hatano, Naomichi

2017-10-01

The electronic thermoelectric coefficients are analyzed in the vicinity of one and two Anderson localization thresholds in three dimensions. For a single mobility edge, we correct and extend previous studies and find universal approximants which allow us to deduce the critical exponent for the zero-temperature conductivity from thermoelectric measurements. In particular, we find that at nonzero low temperatures the Seebeck coefficient and the thermoelectric efficiency can be very large on the "insulating" side, for chemical potentials below the (zero-temperature) localization threshold. Corrections to the leading power-law singularity in the zero-temperature conductivity are shown to introduce nonuniversal temperature-dependent corrections to the otherwise universal functions which describe the Seebeck coefficient, the figure of merit, and the Wiedemann-Franz ratio. Next, the thermoelectric coefficients are shown to have interesting dependences on the system size. While the Seebeck coefficient decreases with decreasing size, the figure of merit first decreases but then increases, while the Wiedemann-Franz ratio first increases but then decreases as the size decreases. Small (but finite) samples may thus have larger thermoelectric efficiencies. In the last part we study thermoelectricity in systems with a pair of localization edges, the ubiquitous situation in random systems near the centers of electronic energy bands. As the disorder increases, the two thresholds approach each other, and then the Seebeck coefficient and the figure of merit increase significantly, as expected from the general arguments of Mahan and Sofo [J. D. Mahan and J. O. Sofo, Proc. Natl. Acad. Sci. USA 93, 7436 (1996), 10.1073/pnas.93.15.7436] for a narrow energy range of the zero-temperature metallic behavior.

Localization of soft modes at the depinning transition

NASA Astrophysics Data System (ADS)

Cao, Xiangyu; Bouzat, Sebastian; Kolton, Alejandro B.; Rosso, Alberto

2018-02-01

We characterize the soft modes of the dynamical matrix at the depinning transition, and compare the matrix with the properties of the Anderson model (and long-range generalizations). The density of states at the edge of the spectrum displays a universal linear tail, different from the Lifshitz tails. The eigenvectors are instead very similar in the two matrix ensembles. We focus on the ground state (soft mode), which represents the epicenter of avalanche instabilities. We expect it to be localized in all finite dimensions, and make a clear connection between its localization length and the Larkin length of the depinning model. In the fully connected model, we show that the weak-strong pinning transition coincides with a peculiar localization transition of the ground state.

The topological Anderson insulator phase in the Kane-Mele model

NASA Astrophysics Data System (ADS)

Orth, Christoph P.; Sekera, Tibor; Bruder, Christoph; Schmidt, Thomas L.

2016-04-01

It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase.

Three-dimensional local residual stress and orientation gradients near graphite nodules in ductile cast iron [3D local residual stress and orientation gradients near graphite nodules in ductile cast iron

DOE PAGES

Zhang, Y. B.; Andriollo, T.; Faester, S.; ...

2016-09-14

A synchrotron technique, differential aperture X-ray microscopy (DAXM), has been applied to characterize the microstructure and analyze the local mesoscale residual elastic strain fields around graphite nodules embedded in ferrite matrix grains in ductile cast iron. Compressive residual elastic strains are measured with a maximum strain of ~6.5–8 × 10 –4 near the graphite nodules extending into the matrix about 20 μm, where the elastic strain is near zero. The experimental data are compared with a strain gradient calculated by a finite element model, and good accord has been found but with a significant overprediction of the maximum strain. Thismore » is discussed in terms of stress relaxation during cooling or during storage by plastic deformation of the nodule, the matrix or both. Furthermore, relaxation by plastic deformation of the ferrite is demonstrated by the formation of low energy dislocation cell structure also quantified by the DAXM technique.« less

Geology and coal resources of the Hanging Woman Creek Study Area, Big Horn and Powder River Counties, Montana

USGS Publications Warehouse

Culbertson, William Craven; Hatch, Joseph R.; Affolter, Ronald H.

1978-01-01

In an area of 7,200 acres (29 sq km) In the Hanging Woman Creek study area, the Anderson coal bed contains potentially surface minable resources of 378 million short tons (343 million metric tons) of subbituminous C coal that ranges in thickness from 26 to 33 feet (7.9-10.1 m) at depths of less than 200 feet (60 m). Additional potentially surface minable resources of 55 million short tons (50 million metric tons) are contained in the 9-12 foot (2.7-3.7 m) thick Dietz coal bed which lies 50-100 feet (15-30 m) below the Anderson. Analyses of coal from 5 core holes indicates that the Anderson bed contains 0.4 percent sulfur, 5 percent ash, and has a heating value of 8,540 Btu/lb (4,750 Kcal/kg). The trace element content of the coal is generally similar to other coals in the Powder River Basin. The two coal beds are in the Fort Union Formation of Paleocene age which consists of sandstone, siltstone, shale, coal beds, and locally impure limestone. A northeast-trending normal fault through the middle of the area, downthrown on the southeast side, has displaced the generally flat lying strata as much as 300 feet (91 m). Most of the minable coal lies northwest of this fault.

Role of Hf on Phase Formation in Ti45Zr(38-x)Hf(x)Ni17 Liquids and Solids

NASA Technical Reports Server (NTRS)

Wessels, V.; Sahu, K. K.; Gangopadhyay, A. K.; Huett, V. T.; Canepari, S.; Goldman, A. I.; Hyers, R. W.; Kramer, M. J.; Rogers, J. R.; Kelton, K. F.;

Limitation of Shrinkage Porosity in Aluminum Rotor Die Casting

NASA Astrophysics Data System (ADS)

Kim, Young-Chan; Choi, Se-Weon; Kim, Cheol-Woo; Cho, Jae-Ik; Lee, Sung-Ho; Kang, Chang-Seog

Aluminum rotor prone to have many casting defects especially large amount of air and shrinkage porosity, which caused eccentricity, loss and noise during motor operation. Many attempts have been made to develop methods of shrinkage porosity control, but still there are some problems to solve. In this research, the process of vacuum squeeze die casting is proposed for limitation of defects. The 6 pin point gated dies which were in capable of local squeeze at the end ring were used. Influences of filling patterns on HPDC were evaluated and the important process control parameters were high injection speed, squeeze length, venting and process conditions. By using local squeeze and vacuum during filling and solidification, air and shrinkage porosity were significantly reduced and the feeding efficiency at the upper end ring was improved 10%. As a result of controlling the defects, the dynamometer test showed improved motor efficiency by more than 4%.

Two-dimensional conductors with interactions and disorder from particle-vortex duality

DOE PAGES

Goldman, H.; Mulligan, M.; Raghu, S.; ...

2017-12-27

Here, we study Dirac fermions in two spatial dimensions (2D) coupled to strongly fluctuating U(1) gauge fields in the presence of quenched disorder. Such systems are dual to theories of free Dirac fermions, which are vortices of the original theory. In analogy to superconductivity, when these fermionic vortices localize, the original system becomes a perfect conductor, and when the vortices possess a finite conductivity, the original fermions do as well. We provide several realizations of this principle and thereby introduce examples of strongly interacting 2D metals that evade Anderson localization.

Two-dimensional conductors with interactions and disorder from particle-vortex duality

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

Goldman, H.; Mulligan, M.; Raghu, S.

Here, we study Dirac fermions in two spatial dimensions (2D) coupled to strongly fluctuating U(1) gauge fields in the presence of quenched disorder. Such systems are dual to theories of free Dirac fermions, which are vortices of the original theory. In analogy to superconductivity, when these fermionic vortices localize, the original system becomes a perfect conductor, and when the vortices possess a finite conductivity, the original fermions do as well. We provide several realizations of this principle and thereby introduce examples of strongly interacting 2D metals that evade Anderson localization.

Doping of Semiconducting Atomic Chains

NASA Technical Reports Server (NTRS)

Toshishige, Yamada; Kutler, Paul (Technical Monitor)

1997-01-01

Due to the rapid progress in atom manipulation technology, atomic chain electronics would not be a dream, where foreign atoms are placed on a substrate to form a chain, and its electronic properties are designed by controlling the lattice constant d. It has been shown theoretically that a Si atomic chain is metallic regardless of d and that a Mg atomic chain is semiconducting or insulating with a band gap modified with d. For electronic applications, it is essential to establish a method to dope a semiconducting chain, which is to control the Fermi energy position without altering the original band structure. If we replace some of the chain atoms with dopant atoms randomly, the electrons will see random potential along the chain and will be localized strongly in space (Anderson localization). However, if we replace periodically, although the electrons can spread over the chain, there will generally appear new bands and band gaps reflecting the new periodicity of dopant atoms. This will change the original band structure significantly. In order to overcome this dilemma, we may place a dopant atom beside the chain at every N lattice periods (N > 1). Because of the periodic arrangement of dopant atoms, we can avoid the unwanted Anderson localization. Moreover, since the dopant atoms do not constitute the chain, the overlap interaction between them is minimized, and the band structure modification can be made smallest. Some tight-binding results will be discussed to demonstrate the present idea.

Focused Molding Using Adhesive Pads in Mehta Casting for Early-Onset Scoliosis.

PubMed

Abraham, Roby; Sponseller, Paul D

2014-11-01

Prospective clinical series. To determine the effect of adhesive pads placed over the apex of scoliosis curves on curve correction 1) after the first cast and 2) after the final cast. Early-onset scoliosis is often effectively managed by serial casting. Properly localizing the apex of the molds with the cast in place is challenging. The authors explored the effectiveness of a novel technique: incorporation of adhesive pads placed over the major curve apex before Mehta casting. The 27 patients who received body casts (2000-2013) were divided into 2 groups: those without and with apical adhesive pads (5-6 layers of pads placed on the major curve's apex during casting): non-pad (NP) group (n = 12) and pad (P) group (n = 15), respectively. Groups were compared regarding the percentage of Cobb angle change from the first cast and curve correction to a Cobb angle of <25° with Student t and chi-square tests (significance was p < .05). The mean percentage of major first-cast curve correction was 39% ± 18% and 56% ± 17% in the NP and P groups, respectively. Of the 26 patients out of a cast, 11 (42%) had a Cobb angle of <25°: 3 (25%) and 8 (57%) in the NP and P groups, respectively. The mean differences between the 2 groups in percentage of major curve correction and this Cobb angle correction were significant: p = .023 and .005, respectively. Adhesive pads placed over major curve(s) during Mehta casting were effective in increasing the amount of major curve correction from the first cast for idiopathic early-onset scoliosis and in decreasing curves to <25° at final follow-up. Copyright © 2014 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

Strain Rate Dependency of Bronze Metal Matrix Composite Mechanical Properties as a Function of Casting Technique

NASA Astrophysics Data System (ADS)

Brown, Lloyd; Joyce, Peter; Radice, Joshua; Gregorian, Dro; Gobble, Michael

2012-07-01

Strain rate dependency of mechanical properties of tungsten carbide (WC)-filled bronze castings fabricated by centrifugal and sedimentation-casting techniques are examined, in this study. Both casting techniques are an attempt to produce a functionally graded material with high wear resistance at a chosen surface. Potential applications of such materials include shaft bushings, electrical contact surfaces, and brake rotors. Knowledge of strain rate-dependent mechanical properties is recommended for predicting component response due to dynamic loading or impact events. A brief overview of the casting techniques for the materials considered in this study is followed by an explanation of the test matrix and testing techniques. Hardness testing, density measurement, and determination of the volume fraction of WC particles are performed throughout the castings using both image analysis and optical microscopy. The effects of particle filling on mechanical properties are first evaluated through a microhardness survey of the castings. The volume fraction of WC particles is validated using a thorough density survey and a rule-of-mixtures model. Split Hopkinson Pressure Bar (SHPB) testing of various volume fraction specimens is conducted to determine strain dependence of mechanical properties and to compare the process-property relationships between the two casting techniques. The baseline performances of C95400 bronze are provided for comparison. The results show that the addition of WC particles improves microhardness significantly for the centrifugally cast specimens, and, to a lesser extent, in the sedimentation-cast specimens, largely because the WC particles are more concentrated as a result of the centrifugal-casting process. Both metal matrix composites (MMCs) demonstrate strain rate dependency, with sedimentation casting having a greater, but variable, effects on material response. This difference is attributed to legacy effects from the casting process, namely, porosity and localized WC particle grouping.

Transition to Complicated Behavior in Infinite Dimensional Dynamical Systems

DTIC Science & Technology

1990-03-01

solitons in nonlinear refractive periodic media," Phys. Lett. A. 141 37 (1989). A.3. Dynamics of Free-Running and Injection- Locked Laser Diode Arrays...Fibers * Dynamics of Free-Running and Injection- Locked Laser Diode Arrays I Diffraction/Diffusion Mediated Instabilities in Self-focusing/Defocusing...optics, the interplay between the coherence of solitons and the scattering (Anderson localization) effects of randomness, and the value in looking at

Disorder effects in the evolution from BCS to BEC superfluidity

NASA Astrophysics Data System (ADS)

Han, Li; de Melo, Carlos A. R. Sa

2009-03-01

We discuss the effects of disorder on the critical temperature of superfluids during the evolution from BCS to BEC. For s-wave superfluids we find that the critical temperature is weakly affected by disorder in the BCS regime as described in Anderson’s theorem, even less affected by disorder at zero chemical potential (near unitarity), but strongly affected by disorder in the BEC regime, where Anderson's theorem does not apply. This suggests that the superfluid is more robust to the effects of disorder at the interaction parameter where the chemical potential vanishes (close to unitarity). We construct a three dimensional phase diagram of critical temperature, disorder and interaction parameter [1], and show that there are regions of localized superfluidity, as well as insulating regions due to Anderson localization of fermions (BCS regime) and molecular bosons (BEC regime). The phase diagram for higher angular momentum (e.g. p-wave and d-wave) is also analyzed, where the effects of disorder are much more dramatic in the BCS regime in comparison to the s-wave case because pair breaking is strong, while the disorder effects in BEC regime are similar to what occurs in the s-wave case. [1] Li Han, C. A. R. Sa de Melo, arXiv:0812.xxxx

Field-controlled magnetic order with insulator-metal transitions in a periodic Anderson-like organic polymer.

PubMed

Ding, L J; Yao, K L; Fu, H H

2011-01-07

The zero- and low-temperature behaviors of a quasi-one-dimensional organic polymer proposed as a symmetrical periodic Anderson-like chain model, in which the localized f orbitals hybridize with the conduction orbitals at even sites, are investigated by means of many-body Green's function theory. In the absence of magnetic field, the ground state of the system turns out to be ferrimagnetic. The temperature-induced phase diagrams have been explored, where the competition between the Hubbard repulsion U on the localized f orbital and the hybridization strength V makes an important impact on the transition temperature. In a magnetic field, it is found that a 1/3 magnetization plateau appears and two critical fields indicating the insulator-metal transitions at zero temperature emerge, which are closely related to the energy bands. Furthermore, the single-site entanglement entropy is a good indicator of quantum phase transitions. The temperature-field-induced phase diagram has also been attained, wherein the magnetization plateau state, the gapless phase and the spin polarized state are revealed. The temperature dependence of thermodynamic quantities such as the magnetization, susceptibility and specific heat are calculated to characterize the corresponding phases. It is also found that the up-spin and down-spin hole excitations are responsible for the thermodynamic properties.

Phonon localization transition in relaxor ferroelectric PZN-5%PT

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

Manley, Michael E.; Christianson, Andrew D.; Abernathy, Douglas L.

Relaxor ferroelectric behavior occurs in many disordered ferroelectric materials but is not well understood at the atomic level. Recent experiments and theoretical arguments indicate that Anderson localization of phonons instigates relaxor behavior by driving the formation of polar nanoregions (PNRs). Here, we use inelastic neutron scattering to observe phonon localization in relaxor ferroelectric PZN-5%PT (0.95[Pb(Zn 1/3 Nb 2/3)O 3]–0.05PbTiO 3) and detect additional features of the localization process. In the lead, up to phonon localization on cooling, the local resonant modes that drive phonon localization increase in number. The increase in resonant scattering centers is attributed to a known increasemore » in the number of locally off centered Pb atoms on cooling. The transition to phonon localization occurs when these random scattering centers increase to a concentration where the Ioffe-Regel criterion is satisfied for localizing the phonon. Finally, we also model the effects of damped mode coupling on the observed phonons and phonon localization structure.« less

Phonon localization transition in relaxor ferroelectric PZN-5%PT

DOE PAGES

Manley, Michael E.; Christianson, Andrew D.; Abernathy, Douglas L.; ...

2017-03-27

Relaxor ferroelectric behavior occurs in many disordered ferroelectric materials but is not well understood at the atomic level. Recent experiments and theoretical arguments indicate that Anderson localization of phonons instigates relaxor behavior by driving the formation of polar nanoregions (PNRs). Here, we use inelastic neutron scattering to observe phonon localization in relaxor ferroelectric PZN-5%PT (0.95[Pb(Zn 1/3 Nb 2/3)O 3]–0.05PbTiO 3) and detect additional features of the localization process. In the lead, up to phonon localization on cooling, the local resonant modes that drive phonon localization increase in number. The increase in resonant scattering centers is attributed to a known increasemore » in the number of locally off centered Pb atoms on cooling. The transition to phonon localization occurs when these random scattering centers increase to a concentration where the Ioffe-Regel criterion is satisfied for localizing the phonon. Finally, we also model the effects of damped mode coupling on the observed phonons and phonon localization structure.« less

Oxidation feature and diffusion mechanism of Zr-based metallic glasses near the glass transition point

NASA Astrophysics Data System (ADS)

Hu, Zheng; Lei, Xianqi; Wang, Yang; Zhang, Kun

2018-03-01

The oxidation behaviors of as-cast, pre-deformed, and crystallized Zr47.9Ti0.3Ni3.1Cu39.3Al9.4 metallic glasses (MGs) were studied near the glass transition point. The oxidation kinetics of the crystallized MGs followed a parabolic-rate law, and the as-cast and pre-deformed MGs exerted a typical two-stage behavior above the glass transition temperature (T g). Most interesting, pre-deformed treatment can significantly improve the oxidation rate of MGs, as the initial oxidation appeared earlier than for the as-cast MGs, and was accompanied by much thicker oxide scale. The EDS and XPS results showed that the metal Al acted as the preferred scavenger that absorbed intrinsic oxygen in the near-surface region of as-cast MGs. However, a homogeneous mixed layer without Al was observed in the pre-deformed MGs. We speculated the accelerated diffusion of other elements in the MGs was due to the local increase in the free volume and significant shear-induced dilation of the local structure. The results from this study demonstrate that MGs exhibit controllable atomic diffusion during the oxidation process, which can facilitate use in super-cooled liquid region applications.

Effect of porosity on ductility variation in investment cast 17-4PH.

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

Wright, Robert D.; Kilgo, Alice C.; Grant, Richard P.

2005-02-01

The stainless steel alloy 17-4PH contains a martensitic microstructure and second phase delta ({delta}) ferrite. Strengthening of 17-4PH is attributed to Cu-rich precipitates produced during age hardening treatments at 900-1150 F (H900-H1150). For wrought 17-4PH, the effects of heat treatment and microstructure on mechanical properties are well-documented [for example, Ref. 1]. Fewer studies are available on cast 17-4PH, although it has been a popular casting alloy for high strength applications where moderate corrosion resistance is needed. Microstructural features and defects particular to castings may have adverse effects on properties, especially when the alloy is heat treated to high strength. Themore » objective of this work was to outline the effects of microstructural features specific to castings, such as shrinkage/solidification porosity, on the mechanical behavior of investment cast 17-4PH. Besides heat treatment effects, the results of metallography and SEM studies showed that the largest effect on mechanical properties is from shrinkage/solidification porosity. Figure 1a shows stress-strain curves obtained from samples machined from castings in the H925 condition. The strength levels were fairly similar but the ductility varied significantly. Figure 1b shows an example of porosity on a fracture surface from a room-temperature, quasi-static tensile test. The rounded features represent the surfaces of dendrites which did not fuse or only partially fused together during solidification. Some evidence of local areas of fracture is found on some dendrite surfaces. The shrinkage pores are due to inadequate backfilling of liquid metal and simultaneous solidification shrinkage during casting. A summary of percent elongation results is displayed in Figure 2a. It was found that higher amounts of porosity generally result in lower ductility. Note that the porosity content was measured on the fracture surfaces. The results are qualitatively similar to those found by Gokhale et al. and Surappa et al. in cast A356 Al and by Gokhale et al. for a cast Mg alloys. The quantitative fractography and metallography work by Gokhale et al. illustrated the strong preference for fracture in regions of porosity in cast material. That is, the fracture process is not correlated to the average microstructure in the material but is related to the extremes in microstructure (local regions of high void content). In the present study, image analysis on random cross-sections of several heats indicated an overall porosity content of 0.03%. In contrast, the area % porosity was as high as 16% when measured on fracture surfaces of tensile specimens using stereology techniques. The results confirm that the fracture properties of cast 17-4PH cannot be predicted based on the overall 'average' porosity content in the castings.« less

Field emission properties and strong localization effect in conduction mechanism of nanostructured perovskite LaNiO{sub 3}

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

Kamble, Ramesh B., E-mail: rbk.physics@coep.ac.in; Department of Physics, College of Engineering, Pune 411005, Maharashtra; Tanty, Narendra

2016-08-22

We report the potential field emission of highly conducting metallic perovskite lanthanum nickelate (LaNiO{sub 3}) from the nanostructured pyramidal and whisker shaped tips as electron emitters. Nano particles of lanthanum nickelate (LNO) were prepared by sol-gel route. Structural and morphological studies have been carried out. Field emission of LNO exhibited high emission current density, J = 3.37 mA/cm{sup 2} at a low threshold electric field, E{sub th} = 16.91 V/μm, obeying Fowler–Nordheim tunneling. The DC electrical resistivity exhibited upturn at 11.6 K indicating localization of electron at low temperature. Magnetoresistance measurement at different temperatures confirmed strong localization in nanostructured LNO obeying Anderson localization effect at low temperature.

Corrosion and protection of heterogeneous cast Al-Si (356) and Al-Si-Cu-Fe (380) alloys by chromate adn cerium inhibitors

NASA Astrophysics Data System (ADS)

Jain, Syadwad

In this study, the localized corrosion and conversion coating on cast alloys 356 (Al-7.0Si-0.3Mg) and 380 (Al-8.5Si-3.5Cu-1.6Fe) were characterized. The intermetallic phases presence in the permanent mold cast alloy 356 are primary-Si, Al5FeSi, Al8Si6Mg3Fe and Mg2Si. The die cast alloy 380 is rich in Cu and Fe elements. These alloying elements result in formation of the intermetallic phases Al 5FeSi, Al2Cu and Al(FeCuCr) along with primary-Si. The Cu- and Fe-rich IMPS are cathodic with respect to the matrix phase and strongly govern the corrosion behavior of the two cast alloys in an aggressive environment due to formation of local electrochemical cell in their vicinity. Results have shown that corrosion behavior of permanent mould cast alloy 356 is significantly better than the die cast aluminum alloy 380, primarily due to high content of Cu- and Fe-rich phases such as Al2Cu and Al 5FeSi in the latter. The IMPS also alter the protection mechanism of the cast alloys in the presence of inhibitors in an environment. The presence of chromate in the solution results in reduced cathodic activity on all the phases. Chromate provides some anodic inhibition by increasing pitting potentials and altering corrosion potentials for the phases. Results have shown that performance of CCC was much better on 356 than on 380, primarily due to inhomogeneous and incomplete coating deposition on Cu- and Fe- phases present in alloy 380. XPS and Raman were used to characterize coating deposition on intermetallics. Results show evidence of cyanide complex formation on the intermetallic phases. The presence of this complex is speculated to locally suppress CCC formation. Formation and breakdown of cerium conversion coatings on 356 and 380 was also analyzed. Results showed that deposition of cerium hydroxide started with heavy precipitation on intermetallic particles with the coatings growing outwards onto the matrix. Electrochemical analysis of synthesized intermetallics compounds in the presence of soluble cerium cations showed that of anodic and cathodic activity was not as strongly inhibited as was observed for chromate ions. Overall cerium conversion coating showed good performance on Al-Si (356) ally, but poor performance on Fe- and Cu-rich alloy (380).

A memorial colloquium honoring Herbert L. Anderson

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

Nagle, D.E.

This paper is the result of a colloquium honoring Herbert Anderson. The paper contains memorial statements to the late Mr. Anderson and reports on; chemical analysis of the 1988 Soviet mission to Mars, Mammalian cell genetic regulation and the nature of cancer, and clean atmosphere and nuclear reactors. (JEF)

Award for Distinguished Scientific Early Career Contributions to Psychology: Adam K. Anderson

ERIC Educational Resources Information Center

American Psychologist, 2009

2009-01-01

Adam K. Anderson, recipient of the Award for Distinguished Scientific Early Career Contributions to Psychology, is cited for his outstanding contribution to understanding the representation of emotion and its influence on cognition. By combining psychological and neuroscience techniques with rigorous and creative experimental designs, Anderson has…

Log-Multiplicative Association Models as Item Response Models

ERIC Educational Resources Information Center

Anderson, Carolyn J.; Yu, Hsiu-Ting

2007-01-01

Log-multiplicative association (LMA) models, which are special cases of log-linear models, have interpretations in terms of latent continuous variables. Two theoretical derivations of LMA models based on item response theory (IRT) arguments are presented. First, we show that Anderson and colleagues (Anderson & Vermunt, 2000; Anderson & Bockenholt,…

Some comments on Anderson and Pospahala's correction of bias in line transect sampling

USGS Publications Warehouse

Anderson, D.R.; Burnham, K.P.; Chain, B.R.

1980-01-01

ANDERSON and POSPAHALA (1970) investigated the estimation of wildlife population size using the belt or line transect sampling method and devised a correction for bias, thus leading to an estimator with interesting characteristics. This work was given a uniform mathematical framework in BURNHAM and ANDERSON (1976). In this paper we show that the ANDERSON-POSPAHALA estimator is optimal in the sense of being the (unique) best linear unbiased estimator within the class of estimators which are linear combinations of cell frequencies, provided certain assumptions are met.

Geologic interpretation of gravity data from the Date Creek basin and adjacent areas, west-central Arizona

USGS Publications Warehouse

Otton, James K.; Wynn, Jeffrey C.

1978-01-01

A gravity survey of the Date Creek Basin and adjacent areas was conducted in June 1977 to provide information for the interpretation of basin geology. A comparison of facies relations in the locally uraniferous Chapin Wash Formation and the position of the Anderson mine gravity anomaly in the Date Creek Basin suggested that a relationship between gravity lows and the development of thick lacustrine sections in the region might exist. A second-order residual gravity map derived from the complete Bouguer gravity map for the survey area (derived from survey data and pre-existing U.S. Department of Defense data) shows an excellent correspondence between gravity lows and sediment-filled basins and suggests considerable variation in basin-fill thickness. Using the Anderson mine anomaly as a model, gravity data and facies relations suggest that the southeastern flank of the Aguila Valley gravity low and the gravity low at the western end of the Hassayampa Plain are likely areas for finding thick sections of tuffaceous lacustrine rocks.

Calibration of an M L scale for South Africa using tectonic earthquake data recorded by the South African National Seismograph Network: 2006 to 2009

NASA Astrophysics Data System (ADS)

Saunders, Ian; Ottemöller, Lars; Brandt, Martin B. C.; Fourie, Christoffel J. S.

2013-04-01

A relation to determine local magnitude ( M L) based on the original Richter definition is empirically derived from synthetic Wood-Anderson seismograms recorded by the South African National Seismograph Network. In total, 263 earthquakes in the distance range 10 to 1,000 km, representing 1,681 trace amplitudes measured in nanometers from synthesized Wood-Anderson records on the vertical channel were considered to derive an attenuation relation appropriate for South Africa through multiple regression analysis. Additionally, station corrections were determined for 26 stations during the regression analysis resulting in values ranging between -0.31 and 0.50. The most appropriate M L scale for South Africa from this study satisfies the equation: {M_{{{L}}}} = {{lo}}{{{g}}_{{10}}}(A) + 1.149{{lo}}{{{g}}_{{10}}}(R) + 0.00063R + 2.04 - S The anelastic attenuation term derived from this study indicates that ground motion attenuation is significantly different from Southern California but comparable with stable continental regions.

A Re-Examination of the Community of Inquiry Framework: Social Network and Content Analysis

ERIC Educational Resources Information Center

Shea, Peter; Hayes, Suzanne; Vickers, Jason; Gozza-Cohen, Mary; Uzuner, Sedef; Mehta, Ruchi; Valchova, Anna; Rangan, Prahalad

2010-01-01

This study provides a simultaneous examination of all components of the Community of Inquiry (CoI) framework (Garrison, Anderson & Archer, 2000; Anderson, Rourke, Garrison & Archer, 2001; and Rourke, Garrison, Anderson & Archer, 1999) and seeks to extend previous work into the nature, development, and relationships between the constructs of…

Human Symbol Manipulation within an Integrated Cognitive Architecture

ERIC Educational Resources Information Center

Anderson, John R.

2005-01-01

This article describes the Adaptive Control of Thought-Rational (ACT-R) cognitive architecture (Anderson et al., 2004; Anderson & Lebiere, 1998) and its detailed application to the learning of algebraic symbol manipulation. The theory is applied to modeling the data from a study by Qin, Anderson, Silk, Stenger, & Carter (2004) in which children…

Criticality in the quantum kicked rotor with a smooth potential.

PubMed

Dutta, Rina; Shukla, Pragya

2008-09-01

We investigate the possibility of an Anderson-type transition in the quantum kicked rotor with a smooth potential due to dynamical localization of the wave functions. Our results show the typical characteristics of a critical behavior, i.e., multifractal eigenfunctions and a scale-invariant level statistics at a critical kicking strength which classically corresponds to a mixed regime. This indicates the existence of a localization to delocalization transition in the quantum kicked rotor. Our study also reveals the possibility of other types of transition in the quantum kicked rotor, with a kicking strength well within the strongly chaotic regime. These transitions, driven by the breaking of exact symmetries, e.g., time reversal and parity, are similar to weak-localization transitions in disordered metals.

Localization Transition Induced by Learning in Random Searches

NASA Astrophysics Data System (ADS)

Falcón-Cortés, Andrea; Boyer, Denis; Giuggioli, Luca; Majumdar, Satya N.

2017-10-01

We solve an adaptive search model where a random walker or Lévy flight stochastically resets to previously visited sites on a d -dimensional lattice containing one trapping site. Because of reinforcement, a phase transition occurs when the resetting rate crosses a threshold above which nondiffusive stationary states emerge, localized around the inhomogeneity. The threshold depends on the trapping strength and on the walker's return probability in the memoryless case. The transition belongs to the same class as the self-consistent theory of Anderson localization. These results show that similarly to many living organisms and unlike the well-studied Markovian walks, non-Markov movement processes can allow agents to learn about their environment and promise to bring adaptive solutions in search tasks.

Space Weather Now-Casting for Area-Denied Locations: Testing All-Sky-Imaging Applications at Geomagnetic Conjugate Points.

NASA Astrophysics Data System (ADS)

Baumgardner, J. L.; Mendillo, M.; Martinis, C. R.; Hickey, D. A.; Wroten, J.

2017-12-01

We explore the concept of using an all-sky-imager (ASI) in one hemisphere to provide now-casting of ionospheric perturbations in the opposite hemisphere. The specific example deals with low-latitude plasma instabilities known as equatorial spread-F (ESF) that depend on geomagnetic field controlled electrodynamics. ASI observations of 630.0 nm airglow from 300 km exhibit regions of low emission ("airglow depletions") that correlate highly with ESF patterns of radiowave disruptions, e.g., from GPS satellites. For both oceanographic and geopolitical reasons, there are vast regions of the globe that cannot be used for ground-based now-casting of local ESF effects. For such area-denied locations, it is possible for observations of airglow depletions from the opposite hemisphere to be used to specify both local and conjugate location environmental impacts. We use fifteen months of ASI observations from the El Leoncito Observatory (Argentina) to predict simultaneous conditions at its trans-equatorial geomagnetic conjugate point in Villa de Leyva (Colombia)—validated by independent ASI observations at that location. We find the success rate of conjugate point now-casting to be greater than 95% for large-scale ESF occurrence patterns. For a different pair of stations at higher magnetic latitudes, three years of observations from the Arecibo Observatory (Puerto Rico) were used to make ESF now-casting at its conjugate point in Mercedes (Argentina) with a 85% success rate.

Detecting many-body-localization lengths with cold atoms

NASA Astrophysics Data System (ADS)

Guo, Xuefei; Li, Xiaopeng

2018-03-01

Considering ultracold atoms in optical lattices, we propose experimental protocols to study many-body-localization (MBL) length and criticality in quench dynamics. Through numerical simulations with exact diagonalization, we show that in the MBL phase the perturbed density profile following a local quench remains exponentially localized in postquench dynamics. The size of this density profile after long-time-dynamics defines a localization length, which tends to diverge at the MBL-to-ergodic transition as we increase the system size. The determined localization transition point agrees with previous exact diagonalization calculations using other diagnostics. Our numerical results provide evidence for violation of the Harris-Chayes bound for the MBL criticality. The critical exponent ν can be extracted from our proposed dynamical procedure, which can then be used directly in experiments to determine whether the Harris-Chayes-bound holds for the MBL transition. These proposed protocols to detect localization criticality are justified by benchmarking to the well-established results for the noninteracting three-dimensional Anderson localization.

Assessing Competencies Needed to Engage With Digital Health Services: Development of the eHealth Literacy Assessment Toolkit.

PubMed

Karnoe, Astrid; Furstrand, Dorthe; Christensen, Karl Bang; Norgaard, Ole; Kayser, Lars

2018-05-10

To achieve full potential in user-oriented eHealth projects, we need to ensure a match between the eHealth technology and the user's eHealth literacy, described as knowledge and skills. However, there is a lack of multifaceted eHealth literacy assessment tools suitable for screening purposes. The objective of our study was to develop and validate an eHealth literacy assessment toolkit (eHLA) that assesses individuals' health literacy and digital literacy using a mix of existing and newly developed scales. From 2011 to 2015, scales were continuously tested and developed in an iterative process, which led to 7 tools being included in the validation study. The eHLA validation version consisted of 4 health-related tools (tool 1: "functional health literacy," tool 2: "health literacy self-assessment," tool 3: "familiarity with health and health care," and tool 4: "knowledge of health and disease") and 3 digitally-related tools (tool 5: "technology familiarity," tool 6: "technology confidence," and tool 7: "incentives for engaging with technology") that were tested in 475 respondents from a general population sample and an outpatient clinic. Statistical analyses examined floor and ceiling effects, interitem correlations, item-total correlations, and Cronbach coefficient alpha (CCA). Rasch models (RM) examined the fit of data. Tools were reduced in items to secure robust tools fit for screening purposes. Reductions were made based on psychometrics, face validity, and content validity. Tool 1 was not reduced in items; it consequently consists of 10 items. The overall fit to the RM was acceptable (Anderson conditional likelihood ratio, CLR=10.8; df=9; P=.29), and CCA was .67. Tool 2 was reduced from 20 to 9 items. The overall fit to a log-linear RM was acceptable (Anderson CLR=78.4, df=45, P=.002), and CCA was .85. Tool 3 was reduced from 23 to 5 items. The final version showed excellent fit to a log-linear RM (Anderson CLR=47.7, df=40, P=.19), and CCA was .90. Tool 4 was reduced from 12 to 6 items. The fit to a log-linear RM was acceptable (Anderson CLR=42.1, df=18, P=.001), and CCA was .59. Tool 5 was reduced from 20 to 6 items. The fit to the RM was acceptable (Anderson CLR=30.3, df=17, P=.02), and CCA was .94. Tool 6 was reduced from 5 to 4 items. The fit to a log-linear RM taking local dependency (LD) into account was acceptable (Anderson CLR=26.1, df=21, P=.20), and CCA was .91. Tool 7 was reduced from 6 to 4 items. The fit to a log-linear RM taking LD and differential item functioning into account was acceptable (Anderson CLR=23.0, df=29, P=.78), and CCA was .90. The eHLA consists of 7 short, robust scales that assess individual's knowledge and skills related to digital literacy and health literacy. ©Astrid Karnoe, Dorthe Furstrand, Karl Bang Christensen, Ole Norgaard, Lars Kayser. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 10.05.2018.

Anomalous diffusion in a dynamical optical lattice

NASA Astrophysics Data System (ADS)

Zheng, Wei; Cooper, Nigel R.

2018-02-01

Motivated by experimental progress in strongly coupled atom-photon systems in optical cavities, we study theoretically the quantum dynamics of atoms coupled to a one-dimensional dynamical optical lattice. The dynamical lattice is chosen to have a period that is incommensurate with that of an underlying static lattice, leading to a dynamical version of the Aubry-André model which can cause localization of single-particle wave functions. We show that atomic wave packets in this dynamical lattice generically spread via anomalous diffusion, which can be tuned between superdiffusive and subdiffusive regimes. This anomalous diffusion arises from an interplay between Anderson localization and quantum fluctuations of the cavity field.

Topological superconductor to Anderson localization transition in one-dimensional incommensurate lattices.

PubMed

Cai, Xiaoming; Lang, Li-Jun; Chen, Shu; Wang, Yupeng

2013-04-26

We study the competition of disorder and superconductivity for a one-dimensional p-wave superconductor in incommensurate potentials. With the increase in the strength of the incommensurate potential, the system undergoes a transition from a topological superconducting phase to a topologically trivial localized phase. The phase boundary is determined both numerically and analytically from various aspects and the topological superconducting phase is characterized by the presence of Majorana edge fermions in the system with open boundary conditions. We also calculate the topological Z2 invariant of the bulk system and find it can be used to distinguish the different topological phases even for a disordered system.

Low-Energy Theory of Disordered Graphene

NASA Astrophysics Data System (ADS)

Altland, Alexander

2006-12-01

At low values of external doping, graphene displays a wealth of unconventional transport properties. Perhaps most strikingly, it supports a robust “metallic” regime, with universal conductance of the order of the conductance quantum. We here apply a combination of mean-field and bosonization methods to explore the large scale transport properties of the system. We find that, irrespective of the doping level, disordered graphene is subject to the common mechanisms of Anderson localization. However, at low doping a number of renormalization mechanisms conspire to protect the conductivity of the system, to an extend that strong localization may not be seen even at temperatures much smaller than those underlying present experimental work.

Automated flaw detection scheme for cast austenitic stainless steel weld specimens using Hilbert-Huang transform of ultrasonic phased array data

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

Khan, Tariq; Majumdar, Shantanu; Udpa, Lalita

2012-05-17

The objective of this work is to develop processing algorithms to detect and localize flaws using ultrasonic phased-array data. Data was collected on cast austenitic stainless stell (CASS) weld specimens onloan from the U.S. nuclear power industry' Pressurized Walter Reactor Owners Group (PWROG) traveling specimen set. Each specimen consists of a centrifugally cast stainless stell (CCSS) pipe section welded to a statically cst(SCSS) or wrought (WRSS) section. The paper presents a novel automated flaw detection and localization scheme using low frequency ultrasonic phased array inspection singals from the weld and heat affected zone of the based materials. The major stepsmore » of the overall scheme are preprocessing and region of interest (ROI) detection followed by the Hilbert-Huang transform (HHT) of A-scans in the detected ROIs. HHT offers time-frequency-energy distribution for each ROI. The Accumulation of energy in a particular frequency band is used as a classification feature for the particular ROI.« less

Relationships Between Solidification Parameters in A319 Aluminum Alloy

NASA Astrophysics Data System (ADS)

Vandersluis, E.; Ravindran, C.

2018-03-01

The design of high-performance materials depends on a comprehensive understanding of the alloy-specific relationships between solidification and properties. However, the inconsistent use of a particular solidification parameter for presenting materials characterization in the literature impedes inter-study comparability and the interpretation of findings. Therefore, there is a need for accurate expressions relating the solidification parameters for each alloy. In this study, A319 aluminum alloy castings were produced in a permanent mold with various preheating temperatures in order to control metal cooling. Analysis of the cooling curve for each casting enabled the identification of its liquidus, Al-Si eutectic, and solidus temperatures and times. These values led to the calculation of the primary solidification rate, total solidification rate, primary solidification time, and local solidification time for each casting, which were related to each other as well as to the average casting SDAS and material hardness. Expressions for each of their correlations have been presented with high coefficients of determination, which will aid in microstructural prediction and casting design.

Development of a CFD code for casting simulation

NASA Technical Reports Server (NTRS)

Murph, Jesse E.

1993-01-01

Because of high rejection rates for large structural castings (e.g., the Space Shuttle Main Engine Alternate Turbopump Design Program), a reliable casting simulation computer code is very desirable. This code would reduce both the development time and life cycle costs by allowing accurate modeling of the entire casting process. While this code could be used for other types of castings, the most significant reductions of time and cost would probably be realized in complex investment castings, where any reduction in the number of development castings would be of significant benefit. The casting process is conveniently divided into three distinct phases: (1) mold filling, where the melt is poured or forced into the mold cavity; (2) solidification, where the melt undergoes a phase change to the solid state; and (3) cool down, where the solidified part continues to cool to ambient conditions. While these phases may appear to be separate and distinct, temporal overlaps do exist between phases (e.g., local solidification occurring during mold filling), and some phenomenological events are affected by others (e.g., residual stresses depend on solidification and cooling rates). Therefore, a reliable code must accurately model all three phases and the interactions between each. While many codes have been developed (to various stages of complexity) to model the solidification and cool down phases, only a few codes have been developed to model mold filling.

Grain Refinement and Improvement of Solidification Defects in Direct-Chill Cast Billets of A4032 Alloy by Melt Conditioning

NASA Astrophysics Data System (ADS)

Li, Hu-Tian; Zhao, Pizhi; Yang, Rongdong; Patel, Jayesh B.; Chen, Xiangfu; Fan, Zhongyun

2017-10-01

Melt-conditioned, direct-chill (MC-DC) casting is an emerging technology to manipulate the solidification process by melt conditioning via intensive shearing in the sump during DC casting to tailor the solidification microstructure and defect formation. When using MC-DC casting technology in an industrial scale DC cast billet of an A4032 aluminum alloy, significant grain refinement and uniform microstructure can be achieved in the primary α-Al phase with fine secondary dendritic arm spacing (SDAS). Improved macrosegregation is quantitatively characterized and correlated with the suppression of channel segregation. The mechanisms for the prevention of channel segregation are attributed to the increased local cooling rate in the liquid-solid phase region in the sump and the formation of fine equiaxed dendritic grains under intensive melt shearing during MC-DC casting. A critical cooling rate has been identified to be around 0.5 to 1 K/s (°C/s) for the channel segregation to happen in the investigated alloy based on quantitative metallographic results of SDAS. Reduction and refinement of microporosity is attributed to the improved permeability in the liquid-solid phase region estimated by the Kozeny-Carman relationship. The potential improvement in the mechanical properties achievable in MC-DC cast billets is indicated by the finer and more uniform forging streamline in the forgings of MC-DC cast billet.

Multiple spatially localized dynamical states in friction-excited oscillator chains

NASA Astrophysics Data System (ADS)

Papangelo, A.; Hoffmann, N.; Grolet, A.; Stender, M.; Ciavarella, M.

2018-03-01

Friction-induced vibrations are known to affect many engineering applications. Here, we study a chain of friction-excited oscillators with nearest neighbor elastic coupling. The excitation is provided by a moving belt which moves at a certain velocity vd while friction is modelled with an exponentially decaying friction law. It is shown that in a certain range of driving velocities, multiple stable spatially localized solutions exist whose dynamical behavior (i.e. regular or irregular) depends on the number of oscillators involved in the vibration. The classical non-repeatability of friction-induced vibration problems can be interpreted in light of those multiple stable dynamical states. These states are found within a "snaking-like" bifurcation pattern. Contrary to the classical Anderson localization phenomenon, here the underlying linear system is perfectly homogeneous and localization is solely triggered by the friction nonlinearity.

EBSD Study on Grain Boundary and Microtexture Evolutions During Friction Stir Processing of A413 Cast Aluminum Alloy

NASA Astrophysics Data System (ADS)

Shamanian, Morteza; Mostaan, Hossein; Safari, Mehdi; Szpunar, Jerzy A.

2016-07-01

The as-cast Al alloys contain heterogeneous distributions of non-deforming particles due to non-equilibrium solidification effects. Therefore, these alloys have poor tribological and mechanical behaviors. It is well known that using friction stir processing (FSP), very fine microstructure is created in the as-cast Al alloys, while their wear resistance can be improved. In this research work, FSP is used to locally refine a surface layer of the coarse as-cast microstructure of cast A413 Al alloy. The main objective of this study is to investigate the effect of FSP on microstructure and microtexture evolutions in A413 cast Al alloy. The grain boundary character distribution, grain structure, and microtexture evolutions in as-cast and friction stir processed A413 Al alloy are analyzed by electron back scatter diffraction technique. It is found that with the FSP, the fraction of low ∑boundary such as ∑3, 7, and 9 are increased. The obtained results show that there are no deformation texture components in the structure of friction stir processed samples. However, some of the main recrystallization texture components such as BR and cubeND are formed during FSP which indicate the occurrence of dynamic recrystallization phenomenon due to the severe plastic deformation induced by the rotation of tool.

Experimental und numerical investigations on cooling efficiency of Air-Mist nozzles on steel during continuous casting

NASA Astrophysics Data System (ADS)

Arth, G.; Taferner, M.; Bernhard, C.; Michelic, S.

2016-07-01

Cooling strategies in continuous casting of steel can vary from rapid cooling to slow cooling, mainly controlled by adjusting the amount of water sprayed onto the surface of the product. Inadequate adjustment however can lead to local surface undercooling or reheating, leading to surface and inner defects. This paper focuses on cooling efficiency of Air-Mist nozzles on casted steel and the experimental and numerical prediction of surface temperature distributions over the product width. The first part explains the determination of heat transfer coefficients (HTC) on laboratory scale, using a so called nozzle measuring stand (NMS). Based on measured water distributions and determined HTC's for air-mist nozzles using the NMS, surface temperatures are calculated by a transient 2D-model on a simple steel plate, explained in the second part of this paper. Simulations are carried out varying water impact density and spray water distribution, consequently influencing the local HTC distribution over the plate width. Furthermore, these results will be interpreted with regard to their consequence for surface and internal quality of the cast product. The results reveal the difficulty of correct adjustment of the amount of sprayed water, concurrent influencing water distribution and thus changing HTC distribution and surface temperature.

High-Performance Solid-State and Fiber Lasers Controlled by Volume Bragg Gratings

DTIC Science & Technology

2013-09-01

Glebov: Proc. SPIE 8237 (2012) 823705. 12） I. Divliansky, D. Ott, B. Anderson, G. Venus, and L. Glebov: To be published in Opt. Express. 13） A. Jain...B. Anderson, D. Drachenberg, V. Rotar, G. Venus, and L. Glebov: Proc. SPIE 8237 (2012) 823705. 47） B. Anderson, S. Kaim, G. B. Venus, J. Lumeau, V

KENNEDY SPACE CENTER, FLA. -- Sandra Anderson, wife of STS-107 Payload Commander Michael Anderson, visits a new residence hall at the Florida Institute of Technology (FIT) in Melbourne, Fla., named for her late husband. Family members of the STS-107 astronauts, other dignitaries, members of the university community and the public gathered for a dedication ceremony for the Columbia Village at FIT. Each of the seven new residence halls in the complex is named for one of the STS-107 astronauts who perished during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon.

NASA Image and Video Library

2003-10-28

KENNEDY SPACE CENTER, FLA. -- Sandra Anderson, wife of STS-107 Payload Commander Michael Anderson, visits a new residence hall at the Florida Institute of Technology (FIT) in Melbourne, Fla., named for her late husband. Family members of the STS-107 astronauts, other dignitaries, members of the university community and the public gathered for a dedication ceremony for the Columbia Village at FIT. Each of the seven new residence halls in the complex is named for one of the STS-107 astronauts who perished during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon.

Adaptive changes in the motor cortex during and after longterm forelimb immobilization in adult rats.

PubMed

Viaro, Riccardo; Budri, Mirco; Parmiani, Pierantonio; Franchi, Gianfranco

2014-05-15

Experimental and clinical studies have attempted to evaluate the changes in cortical activity seen after immobilization-induced longterm sensorimotor restriction, although results remain controversial. We used intracortical microstimulation (ICMS), which provides topographic movement representations of the motor areas in both hemispheres with optimal spatial characterization, combined with behavioural testing to unravel the effects of limb immobilization on movement representations in the rat primary motor cortex (M1). Unilateral forelimb immobilization in rats was achieved by casting the entire limb and leaving the cast in place for 15 or 30 days. Changes in M1 were bilateral and specific for the forelimb area, but were stronger in the contralateral-to-cast hemisphere. The threshold current required to evoke forelimb movement increased progressively over the period in cast, whereas the forelimb area size decreased and the non-excitable area size increased. Casting resulted in a redistribution of proximal/distal movement representations: proximal forelimb representation increased, whereas distal representation decreased in size. ICMS after cast removal showed a reversal of changes, which remained partial at 15 days. Local application of the GABAA-antagonist bicuculline revealed the impairment of cortical synaptic connectivity in the forelimb area during the period of cast and for up to 15 days after cast removal. Six days of rehabilitation using a rotarod performance protocol after cast removal did not advance map size normalization in the contralateral-to-cast M1 and enabled the cortical output towards the distal forelimb only in sites that had maintained their excitability. These results are relevant to our understanding of adult M1 plasticity during and after sensorimotor deprivation, and to new approaches to conditions that require longterm limb immobilization. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

On the TAP Free Energy in the Mixed p-Spin Models

NASA Astrophysics Data System (ADS)

Chen, Wei-Kuo; Panchenko, Dmitry

2018-05-01

Thouless et al. (Phys Mag 35(3):593-601, 1977), derived a representation for the free energy of the Sherrington-Kirkpatrick model, called the TAP free energy, written as the difference of the energy and entropy on the extended configuration space of local magnetizations with an Onsager correction term. In the setting of mixed p-spin models with Ising spins, we prove that the free energy can indeed be written as the supremum of the TAP free energy over the space of local magnetizations whose Edwards-Anderson order parameter (self-overlap) is to the right of the support of the Parisi measure. Furthermore, for generic mixed p-spin models, we prove that the free energy is equal to the TAP free energy evaluated on the local magnetization of any pure state.

Summary of data acquisition and field operations: Terra Resources, Anderson Canyon No. 3-17, Lincoln County, Wyoming; Terra Resources, North Anderson Canyon No. 40-16, Sweetwater County, Wyoming. Topical report, August 1989

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

Not Available

1989-08-01

A summary is presented of open-hole data collected on two cooperative wells for the GRI Tight Gas Sands Program. The overall objective of gathering well data in the Frontier Formation is to identify and evaluate technological problems in formation evaluation and hydraulic fracturing. Open-hole data acquisition is emphasized for the Anderson Canyon No. 3-17, a full cooperative well (i.e., coring, logging, cased-hole stress testing, fracture monitoring). Data collected on the North Anderson Canyon No. 40-16, a partial cooperative well (i.e., logging only), is described in an appendix.

Experimental studies of the effect target geometry on the evolution of laser produced plasma plumes

NASA Astrophysics Data System (ADS)

Beatty, Cuyler; Anderson, Austin; Iratcabal, Jeremy; Dutra, Eric; Covington, Aaron

2016-10-01

The expansion of the laser plumes was shown to be dependent on the initial target geometry. A 16 channel framing camera was used to record the plume shape and propagation speeds were determined from analysis of the images. Plastic targets were manufactured using different methods including 3D printing, CNC machining and vacuum casting. Preliminary target designs were made using a 3D printer and ABS plastic material. These targets were then tested using a 3 J laser with a 5 ns duration pulse. Targets with a deep conical depression were shown to produce highly collimated plumes when compared to flat top targets. Preliminary results of these experiments will be discussed along with planned future experiments that will use the indented targets with a 30 J laser with a 0.8 ns duration pulse in preparation for pinched laser plume experiments at the Nevada Terawatt Facility. Other polymers that are readily available in a deuterated form will also be explored as part of an effort to develop a cost effective plasma plume target for follow on neutron production experiments. Dr. Austin Anderson.

Two mechanisms of disorder-induced localization in photonic-crystal waveguides

NASA Astrophysics Data System (ADS)

García, P. D.; KiršanskÄ--, G.; Javadi, A.; Stobbe, S.; Lodahl, P.

2017-10-01

Unintentional but unavoidable fabrication imperfections in state-of-the-art photonic-crystal waveguides lead to the spontaneous formation of Anderson-localized modes thereby limiting slow-light propagation and its potential applications. On the other hand, disorder-induced cavities offer an approach to cavity-quantum electrodynamics and random lasing at the nanoscale. The key statistical parameter governing the disorder effects is the localization length, which together with the waveguide length determines the statistical transport of light through the waveguide. In a disordered photonic-crystal waveguide, the localization length is highly dispersive, and therefore, by controlling the underlying lattice parameters, it is possible to tune the localization of the mode. In the present work, we study the localization length in a disordered photonic-crystal waveguide using numerical simulations. We demonstrate two different localization regimes in the dispersion diagram where the localization length is linked to the density of states and the photon effective mass, respectively. The two different localization regimes are identified in experiments by recording the photoluminescence from quantum dots embedded in photonic-crystal waveguides.

Characterizing Time Irreversibility in Disordered Fermionic Systems by the Effect of Local Perturbations

NASA Astrophysics Data System (ADS)

Vardhan, Shreya; De Tomasi, Giuseppe; Heyl, Markus; Heller, Eric J.; Pollmann, Frank

2017-07-01

We study the effects of local perturbations on the dynamics of disordered fermionic systems in order to characterize time irreversibility. We focus on three different systems: the noninteracting Anderson and Aubry-André-Harper (AAH) models and the interacting spinless disordered t -V chain. First, we consider the effect on the full many-body wave functions by measuring the Loschmidt echo (LE). We show that in the extended or ergodic phase the LE decays exponentially fast with time, while in the localized phase the decay is algebraic. We demonstrate that the exponent of the decay of the LE in the localized phase diverges proportionally to the single-particle localization length as we approach the metal-insulator transition in the AAH model. Second, we probe different phases of disordered systems by studying the time expectation value of local observables evolved with two Hamiltonians that differ by a spatially local perturbation. Remarkably, we find that many-body localized systems could lose memory of the initial state in the long-time limit, in contrast to the noninteracting localized phase where some memory is always preserved.

Patriot Games: Yes, Indeed, the British Are Coming! But M. T. Anderson's Revolutionary War Novel Is Unlike Anything You've Ever Read

ERIC Educational Resources Information Center

Horning, Kathleen

2006-01-01

This article presents an interview with 38-year-old writer Matthew Tobin Anderson. In the interview, Anderson talks about his experiences, passion for writing, teenage interests, and his relation to the distinguished writer Mark Twain. He also states the importance of liberty and what it takes to be a patriot and a loyalist. Furthermore, Matthew…

The non-commutative topology of two-dimensional dirty superconductors

NASA Astrophysics Data System (ADS)

De Nittis, Giuseppe; Schulz-Baldes, Hermann

2018-01-01

Non-commutative analysis tools have successfully been applied to the integer quantum Hall effect, in particular for a proof of the stability of the Hall conductance in an Anderson localization regime and of the bulk-boundary correspondence. In this work, these techniques are implemented to study two-dimensional dirty superconductors described by Bogoliubov-de Gennes Hamiltonians. After a thorough presentation of the basic framework and the topological invariants, Kubo formulas for the thermal, thermoelectric and spin Hall conductance are analyzed together with the corresponding edge currents.

Emulating weak localization using a solid-state quantum circuit.

PubMed

Chen, Yu; Roushan, P; Sank, D; Neill, C; Lucero, Erik; Mariantoni, Matteo; Barends, R; Chiaro, B; Kelly, J; Megrant, A; Mutus, J Y; O'Malley, P J J; Vainsencher, A; Wenner, J; White, T C; Yin, Yi; Cleland, A N; Martinis, John M

2014-10-14

Quantum interference is one of the most fundamental physical effects found in nature. Recent advances in quantum computing now employ interference as a fundamental resource for computation and control. Quantum interference also lies at the heart of sophisticated condensed matter phenomena such as Anderson localization, phenomena that are difficult to reproduce in numerical simulations. Here, employing a multiple-element superconducting quantum circuit, with which we manipulate a single microwave photon, we demonstrate that we can emulate the basic effects of weak localization. By engineering the control sequence, we are able to reproduce the well-known negative magnetoresistance of weak localization as well as its temperature dependence. Furthermore, we can use our circuit to continuously tune the level of disorder, a parameter that is not readily accessible in mesoscopic systems. Demonstrating a high level of control, our experiment shows the potential for employing superconducting quantum circuits as emulators for complex quantum phenomena.

Strong correlation induced charge localization in antiferromagnets

PubMed Central

Zhu, Zheng; Jiang, Hong-Chen; Qi, Yang; Tian, Chushun; Weng, Zheng-Yu

2013-01-01

The fate of a hole injected in an antiferromagnet is an outstanding issue of strongly correlated physics. It provides important insights into doped Mott insulators closely related to high-temperature superconductivity. Here, we report a systematic numerical study of t-J ladder systems based on the density matrix renormalization group. It reveals a surprising result for the single hole's motion in an otherwise well-understood undoped system. Specifically, we find that the common belief of quasiparticle picture is invalidated by the self-localization of the doped hole. In contrast to Anderson localization caused by disorders, the charge localization discovered here is an entirely new phenomenon purely of strong correlation origin. It results from destructive quantum interference of novel signs picked up by the hole, and since the same effect is of a generic feature of doped Mott physics, our findings unveil a new paradigm which may go beyond the single hole doped system. PMID:24002668

Colloids exposed to random potential energy landscapes: From particle number density to particle-potential and particle-particle interactions

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

Bewerunge, Jörg; Capellmann, Ronja F.; Platten, Florian

2016-07-28

Colloidal particles were exposed to a random potential energy landscape that has been created optically via a speckle pattern. The mean particle density as well as the potential roughness, i.e., the disorder strength, were varied. The local probability density of the particles as well as its main characteristics were determined. For the first time, the disorder-averaged pair density correlation function g{sup (1)}(r) and an analogue of the Edwards-Anderson order parameter g{sup (2)}(r), which quantifies the correlation of the mean local density among disorder realisations, were measured experimentally and shown to be consistent with replica liquid state theory results.

Ein statistisches Modell zum Einfluß der thermischen Bewegung auf NMR-Festkörperspektren

NASA Astrophysics Data System (ADS)

Ploss, W.; Freude, D.; Pfeifer, H.; Schmiedel, H.

Es wird ein statistisches Modell zum Einfluß der thermischen Bewegung auf die NMR-Linienform vorgestellt, das die Verschmälerung von Festkörper-Spektren bei wachsender Temperatur beschreibt. Das Modell geht von der Annahme aus, daß nach einer Ortsveränderung eines Kerns infolge thermischer Bewegung jede beliebige Kernresonanzfrequenz mit der durch das Festkörperspektrum vorgegebenen Wahrscheinlichkeit angenommen werden kann. Am Beispiel der Festkörper-Gaußlinie wird der Unterschied zu dem bekannten Modell von ANDERSON und WEISS verdeutlicht.Translated AbstractA Statistical Model for the Influence of Thermal Motion on N. M. R. Spectra in SolidsA theory is proposed which allows to describe the narrowing of n. m. r.-line width in the presence of thermal motions of the spins. The model is based on the assumption, that the local resonance frequency of a given spin immediately after the jump is distributed according to the n. m. r.-line shape of the rigid lattice. The difference to the well-known ANDERSON-WEISS-model of spectral narrowing is demonstrated for a gaussian line shape.

ToxCast Chemical Landscape: Paving the Road to 21st Century Toxicology.

PubMed

Richard, Ann M; Judson, Richard S; Houck, Keith A; Grulke, Christopher M; Volarath, Patra; Thillainadarajah, Inthirany; Yang, Chihae; Rathman, James; Martin, Matthew T; Wambaugh, John F; Knudsen, Thomas B; Kancherla, Jayaram; Mansouri, Kamel; Patlewicz, Grace; Williams, Antony J; Little, Stephen B; Crofton, Kevin M; Thomas, Russell S

2016-08-15

The U.S. Environmental Protection Agency's (EPA) ToxCast program is testing a large library of Agency-relevant chemicals using in vitro high-throughput screening (HTS) approaches to support the development of improved toxicity prediction models. Launched in 2007, Phase I of the program screened 310 chemicals, mostly pesticides, across hundreds of ToxCast assay end points. In Phase II, the ToxCast library was expanded to 1878 chemicals, culminating in the public release of screening data at the end of 2013. Subsequent expansion in Phase III has resulted in more than 3800 chemicals actively undergoing ToxCast screening, 96% of which are also being screened in the multi-Agency Tox21 project. The chemical library unpinning these efforts plays a central role in defining the scope and potential application of ToxCast HTS results. The history of the phased construction of EPA's ToxCast library is reviewed, followed by a survey of the library contents from several different vantage points. CAS Registry Numbers are used to assess ToxCast library coverage of important toxicity, regulatory, and exposure inventories. Structure-based representations of ToxCast chemicals are then used to compute physicochemical properties, substructural features, and structural alerts for toxicity and biotransformation. Cheminformatics approaches using these varied representations are applied to defining the boundaries of HTS testability, evaluating chemical diversity, and comparing the ToxCast library to potential target application inventories, such as used in EPA's Endocrine Disruption Screening Program (EDSP). Through several examples, the ToxCast chemical library is demonstrated to provide comprehensive coverage of the knowledge domains and target inventories of potential interest to EPA. Furthermore, the varied representations and approaches presented here define local chemistry domains potentially worthy of further investigation (e.g., not currently covered in the testing library or defined by toxicity "alerts") to strategically support data mining and predictive toxicology modeling moving forward.

Calculation of Suspended Sediment Transport by Combined Wave-Current Flows.

DTIC Science & Technology

1994-11-01

Anderson, and Silberg (1985) presented a model that had an eddy viscosity and boundary layer thickness that varied in time. The reference concentration was...sediment model. This model, along with that of Fredsoe, Anderson, and Silberg (1985), are the only two models that account for both the sediment and the...ignores any correlation between the periodic components of the velocity and the concentration. Even in the model of Fredsoe, Anderson, and Silberg (1985

Rib fracture - aftercare

MedlinePlus

... Alternative Names Broken rib - aftercare References Browner BD, Jupiter JB, Krettek C, Anderson PA. Scapula and rib fractures. In: Browner BD, Jupiter JB, Krettek C, Anderson PA, eds. Skeletal Trauma: ...

Induction hardening treatment and simulation for a grey cast iron used in engine cylinder liners

NASA Astrophysics Data System (ADS)

Castellanos-Leal, E. L.; Miranda, D. A.; Coy, A. E.; Barrero, J. G.; González, J. A.; Vesga Rueda, O. P.

2017-01-01

In this research, a technical study of induction hardening in a grey cast iron used in engine cylinder liners manufactured by LAVCO Ltda., a Colombian foundry company, was carried out. Metallurgical parameters such as austenitization temperature, cooling rate, and quenching severity were determined. These factors are exclusively dependent on chemical composition and initial microstructure of grey cast iron. Simulations of induction heating through finite elements method were performed and, the most appropriate experimental conditions to achieve the critical transformation temperature was evaluated to reach a proper surface hardening on the piece. Preliminary results revealed an excellent approximation between simulation and heating test performed with a full bridge inverter voltage adapted with local technology.

Topological approximation of the nonlinear Anderson model

NASA Astrophysics Data System (ADS)

Milovanov, Alexander V.; Iomin, Alexander

2014-06-01

We study the phenomena of Anderson localization in the presence of nonlinear interaction on a lattice. A class of nonlinear Schrödinger models with arbitrary power nonlinearity is analyzed. We conceive the various regimes of behavior, depending on the topology of resonance overlap in phase space, ranging from a fully developed chaos involving Lévy flights to pseudochaotic dynamics at the onset of delocalization. It is demonstrated that the quadratic nonlinearity plays a dynamically very distinguished role in that it is the only type of power nonlinearity permitting an abrupt localization-delocalization transition with unlimited spreading already at the delocalization border. We describe this localization-delocalization transition as a percolation transition on the infinite Cayley tree (Bethe lattice). It is found in the vicinity of the criticality that the spreading of the wave field is subdiffusive in the limit t →+∞. The second moment of the associated probability distribution grows with time as a power law ∝ tα, with the exponent α =1/3 exactly. Also we find for superquadratic nonlinearity that the analog pseudochaotic regime at the edge of chaos is self-controlling in that it has feedback on the topology of the structure on which the transport processes concentrate. Then the system automatically (without tuning of parameters) develops its percolation point. We classify this type of behavior in terms of self-organized criticality dynamics in Hilbert space. For subquadratic nonlinearities, the behavior is shown to be sensitive to the details of definition of the nonlinear term. A transport model is proposed based on modified nonlinearity, using the idea of "stripes" propagating the wave process to large distances. Theoretical investigations, presented here, are the basis for consistency analysis of the different localization-delocalization patterns in systems with many coupled degrees of freedom in association with the asymptotic properties of the transport.

Anderson localization to enhance light-matter interaction (Conference Presentation)

NASA Astrophysics Data System (ADS)

Garcia, Pedro David

2016-04-01

Deliberately introducing disorder in low-dimensional nanostructures like photonic crystal waveguides (PCWs) [1] or photonic crystals (PCs) [2] leads to Anderson localization where light is efficiently trapped by random multiple scattering with the lattice imperfections. These disorder-induced optical modes hace been demonstrated to be very promising for cavity-quantum electrodynamics (QED) experiments where the radiative emission rate of single quantum emitters can be controlled when tuned through resonance with one of these random cavities. Our statistical analysis of the emission dynamics from single quantum dots embeded in disordered PCWs [3] provides detailed insigth about the statistical properties of QED in these complex nanostructures. In addition, using internal light sources reveals new physics in the form of nonuniversal intensity correlations between the different scattered paths within the structure which imprint the local QED properties deep inside the complex structure onto the far-field intensity pattern [2]. Finally, increasing the optical gain in PCWs allows on-chip random nanolasing where the cavity feedback is provided by the intrinsic disorder which enables highly efficient, stable, and broadband tunable lasers with very small mode volumes [4]. The figure of merit of these disorder-induced cavities is their localization length which determines to a large degree the coupling efficiency of a quantum emitter to a disorder-induced cavity as well as the efficiency of random lasing and reveals a strongly dispersive behavior and a non-trivial dependence on disorder in PCWs [5]. [1] L. Sapienza, H. Thyrrestrup, S. Stobbe, P.D. Garcia, S. Smolka, and P. Lodahl, Science 327, 1352 (2010). [2] P. D. García, S. Stobbe, I. Soellner and P. Lodahl, Physical Review Letters 109, 253902 (2012). [3] A. Javadi, S. Maibom, L. Sapienza, H. Thyrrestrup, P.D. Garcia, and P. Lodahl, Opt. Express 22, 30992 (2014). [4] J. Liu, P. D. Garcia, S. Ek, N. Gregersen, T. Suhr, M. Schubert, J. Mørk, S. Stobbe, and P. Lodahl, Nature Nanotechnology, 9, 285 (2014). [5] P.D. Garcia, A. Javadi, and P. Lodahl, In preparation.

Microenvironment -Programmed Metastatic Prostate Cancer Stem Cells (mPCSCs)

DTIC Science & Technology

2016-10-01

accomplished all goals in Aims 1 and 2. Our lab recently relocated from the MD Anderson Cancer Center to Roswell Park Cancer Institute in Buffalo. We ...G. Tang, M.D., Ph.D. CONTRACTING ORGANIZATION: University of Texas MD Anderson Cancer Center Houston, TX 77030 REPORT DATE: October 2016 TYPE OF... Anderson Cancer Center Houston, TX 77030 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical

Visualizing buried silicon atoms at the Cd-Si(111)-7 ×7 interface with localized electrons

NASA Astrophysics Data System (ADS)

Tao, Min-Long; Xiao, Hua-Fang; Sun, Kai; Tu, Yu-Bing; Yuan, Hong-Kuan; Xiong, Zu-Hong; Wang, Jun-Zhong; Xue, Qi-Kun

2017-09-01

We report the atomic-scale imaging of the buried Cd-Si(111)-7 ×7 interface with a low temperature scanning tunneling microscopy (STM). The Cd(0001) films grown on Si(111)-7 ×7 reveal the electronic growth mode, and manifest a series of quantum-well states. In the low-bias STM images, not only the 7 ×7 reconstruction but also individual Si adatoms buried by thick Cd islands are clearly visible. The two successive layers of Cd islands exhibit the distinct contrasts due to the quantum size effect. Moreover, we found a small gap appeared at Fermi level owing to the Anderson localization induced by interface scattering. The perfect transparency of Cd films can be attributed to the anisotropic electron motion, i.e., lateral electron localization and transverse motion like free-electron.

Phonological neighborhood and word frequency effects on the stuttered disfluencies of children who stutter: comments on Anderson (2007).

PubMed

Howell, Peter

2010-10-01

This letter comments on a study by Anderson (2007) that compared the effects of word frequency, neighborhood density, and phonological neighborhood frequency on part-word repetitions, prolongations, and single-syllable word repetitions produced by children who stutter. Anderson discussed her results with respect to 2 theories about stuttering: the covert repair hypothesis and execution planning (EXPLAN) theory. Her remarks about EXPLAN theory are examined. Anderson considered that EXPLAN does not predict the relationship between word and neighborhood frequency and stuttering for part-word repetitions and prolongations (she considered that EXPLAN predicts that stuttering occurs on simple words for children). The actual predictions that EXPLAN makes are upheld by her results. She also considered that EXPLAN cannot account for why stuttering is affected by the same variables that lead to speech errors, and it is shown that this is incorrect. The effects of word frequency, neighborhood density, and phonological neighborhood frequency on part-word repetitions, prolongations, and single-syllable word repetitions reported by Anderson (2007) are consistent with the predictions of the EXPLAN model.

Quality assessment in head and neck oncologic surgery in a Brazilian cancer center compared with MD Anderson Cancer Center benchmarks.

PubMed

Lira, Renan Bezerra; de Carvalho, André Ywata; de Carvalho, Genival Barbosa; Lewis, Carol M; Weber, Randal S; Kowalski, Luiz Paulo

2016-07-01

Quality assessment is a major tool for evaluation of health care delivery. In head and neck surgery, the University of Texas MD Anderson Cancer Center (MD Anderson) has defined quality standards by publishing benchmarks. We conducted an analysis of 360 head and neck surgeries performed at the AC Camargo Cancer Center (AC Camargo). The procedures were stratified into low-acuity procedures (LAPs) or high-acuity procedures (HAPs) and outcome indicators where compared to MD Anderson benchmarks. In the 360 cases, there were 332 LAPs (92.2%) and 28 HAPs (7.8%). Patients with any comorbid condition had a higher incidence of negative outcome indicators (p = .005). In the LAPs, we achieved the MD Anderson benchmarks in all outcome indicators. In HAPs, the rate of surgical site infection and length of hospital stay were higher than what is established by the benchmarks. Quality assessment of head and neck surgery is possible and should be disseminated, improving effectiveness in health care delivery. © 2015 Wiley Periodicals, Inc. Head Neck 38: 1002-1007, 2016. © 2015 Wiley Periodicals, Inc.

Many-Body Localization and Thermalization in Quantum Statistical Mechanics

NASA Astrophysics Data System (ADS)

Nandkishore, Rahul; Huse, David A.

2015-03-01

We review some recent developments in the statistical mechanics of isolated quantum systems. We provide a brief introduction to quantum thermalization, paying particular attention to the eigenstate thermalization hypothesis (ETH) and the resulting single-eigenstate statistical mechanics. We then focus on a class of systems that fail to quantum thermalize and whose eigenstates violate the ETH: These are the many-body Anderson-localized systems; their long-time properties are not captured by the conventional ensembles of quantum statistical mechanics. These systems can forever locally remember information about their local initial conditions and are thus of interest for possibilities of storing quantum information. We discuss key features of many-body localization (MBL) and review a phenomenology of the MBL phase. Single-eigenstate statistical mechanics within the MBL phase reveal dynamically stable ordered phases, and phase transitions among them, that are invisible to equilibrium statistical mechanics and can occur at high energy and low spatial dimensionality, where equilibrium ordering is forbidden.

Tight-binding chains with off-diagonal disorder: Bands of extended electronic states induced by minimal quasi-one-dimensionality

NASA Astrophysics Data System (ADS)

Nandy, Atanu; Pal, Biplab; Chakrabarti, Arunava

2016-08-01

It is shown that an entire class of off-diagonally disordered linear lattices composed of two basic building blocks and described within a tight-binding model can be tailored to generate absolutely continuous energy bands. It can be achieved if linear atomic clusters of an appropriate size are side-coupled to a suitable subset of sites in the backbone, and if the nearest-neighbor hopping integrals, in the backbone and in the side-coupled cluster, bear a certain ratio. We work out the precise relationship between the number of atoms in one of the building blocks in the backbone and that in the side attachment. In addition, we also evaluate the definite correlation between the numerical values of the hopping integrals at different subsections of the chain, that can convert an otherwise point spectrum (or a singular continuous one for deterministically disordered lattices) with exponentially (or power law) localized eigenfunctions to an absolutely continuous spectrum comprising one or more bands (subbands) populated by extended, totally transparent eigenstates. The results, which are analytically exact, put forward a non-trivial variation of the Anderson localization (Anderson P. W., Phys. Rev., 109 (1958) 1492), pointing towards its unusual sensitivity to the numerical values of the system parameters and, go well beyond the other related models such as the Random Dimer Model (RDM) (Dunlap D. H. et al., Phys. Rev. Lett., 65 (1990) 88).

Development in corrosion resistance by microstructural refinement in Zr-16 SS 304 alloy using suction casting technique

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

Das, N., E-mail: nirupamd@barc.gov.in; Sengupta, P.; Abraham, G.

Highlights: • Grain refinement was made in Zr–16 wt.% SS alloy while prepared by suction casting process. • Distribution of Laves phase, e.g., Zr{sub 2}(Fe, Cr) was raised in suction cast (SC) Zr–16 wt.% SS. • Corrosion resistance was improved in SC alloy compared to that of arc-melt-cast alloy. • Grain refinement in SC alloy assisted for an increase in its corrosion resistance. - Abstract: Zirconium (Zr)-stainless steel (SS) hybrid alloys are being considered as baseline alloys for developing metallic-waste-form (MWF) with the motivation of disposing of Zr and SS base nuclear metallic wastes. Zr–16 wt.% SS, a MWF alloymore » optimized from previous studies, exhibit significant grain refinement and changes in phase assemblages (soft phase: Zr{sub 2}(Fe, Cr)/α-Zr vs. hard phase: Zr{sub 3}(Fe, Ni)) when prepared by suction casting (SC) technique in comparison to arc-cast-melt (AMC) route. Variation in Cr-distribution among different phases are found to be low in suction cast alloy, which along with grain refinement restricted Cr-depletion at the Zr{sub 2}(Fe, Cr)/Zr interfaces, prone to localized attack. Hence, SC alloy, compared to AMC alloy, showed lower current density, higher potential at the breakdown of passivity and higher corrosion potential during polarization experiments (carried out under possible geological repository environments, viz., pH 8, 5 and 1) indicating its superior corrosion resistance.« less

Physical, chemical, and isotopic data for samples from the Anderson Springs area, Lake County, California, 1998-1999

USGS Publications Warehouse

Janik, C.J.; Goff, F.; Sorey, M.L.; Rytuba, J.J.; Counce, D.; Colvard, E.M.; Huebner, M.; White, L.D.; Foster, A.

1999-01-01

Anderson Springs is located about 90 miles (145 kilometers) north of San Francisco, California, in the southwestern part of Lake County. The area was first developed in the late 1800s as a health resort, which was active until the 1930s. In the rugged hills to the south of the resort were four small mercury mines of the eastern Mayacmas quicksilver district. About 1,260 flasks of mercury were produced from these mines between 1909 and 1943. In the 1970s, the high-elevation areas surrounding Anderson Springs became part of The Geysers geothermal field. Today, several electric powerplants are located on the ridges above Anderson Springs, utilizing steam produced from a 240°C vapor-dominated reservoir. The primary purpose of this report is to provide physical, chemical, and isotopic data on samples collected in the Anderson Springs area during 1998 and 1999, in response to a Freedom of Information Act request. In July 1998, drainage from the Schwartz adit of the abandoned Anderson mercury mine increased substantially over a 2-day period, transporting a slurry of water and precipitates down a tributary and into Anderson Creek. In August 1998, J.J. Rytuba and coworkers sampled the Schwartz adit drainage and water from the Anderson Springs Hot Spring for base metal and methylmercury analysis. They measured a maximum temperature (Tm) of 85°C in the Hot Spring. Published records show that the temperature of the Anderson Springs Hot Spring (main spring) was 63°C in 1889, 42–52°C from 1974 through 1991, and 77°C in March 1995. To investigate possible changes in thermal spring activity and to collect additional samples for geochemical analysis, C.J. Janik and coworkers returned to the area in September and December 1998. They determined that a cluster of springs adjacent to the main spring had Tm=98°C, and they observed that a new area of boiling vents and small fumaroles (Tm=99.3°C) had formed in an adjacent gully about 20 meters to the north of the main spring. During August–October 1999, several field trips were conducted in the vicinity of Anderson Springs to continue monitoring and sampling the thermal manifestations. The new fumarolic area had increased in temperature and in discharge intensity since 1998, and a zone of dead trees had developed on the steep bank directly west of the fumaroles. Ground temperatures and diffuse flow of CO2 flow through soils were measured in the area surrounding the main spring and new fumaroles and in the zone of tree-kill.

Anderson during EVA 2

NASA Image and Video Library

2010-04-11

ISS023-E-021561 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

Anderson during EVA 2

NASA Image and Video Library

2010-04-11

ISS023-E-021569 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

Anderson during EVA 2

NASA Image and Video Library

2010-04-11

ISS023-E-021562 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

Anderson during EVA 2

NASA Image and Video Library

2010-04-11

ISS023-E-021558 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

Anderson localisation and optical-event horizons in rogue-soliton generation.

PubMed

Saleh, Mohammed F; Conti, Claudio; Biancalana, Fabio

2017-03-06

We unveil the relation between the linear Anderson localisation process and nonlinear modulation instability. Anderson localised modes are formed in certain temporal intervals due to the random background noise. Such localised modes seed the formation of solitary waves that will appear during the modulation instability process at those preferred intervals. Afterwards, optical-event horizon effects between dispersive waves and solitons produce an artificial collective acceleration that favours the collision of solitons, which could eventually lead to a rogue-soliton generation.

Penning Ionization: Measurement of Ion and Molecular Lifetimes.

DTIC Science & Technology

1977-12-01

State of CH", James Carozza and Richard Anderson, J. Opt. Soc. Am. 67, 118 (1977). "Spin & Coherence Transfer in Penning Ionization", L.D. Schearer...Lamp , F. Rev. Sei. Instru. 48, 92 (1977). _^^ ^rtjri ’’Radiative Lifetime of the PrÄ State of CH , James Carroza and Richard ’ Anderson, J. Opt...lr.h .--.- •’••• —•;••.: — - ----- Radiative lifetime of the A2A state of CHr James Carozza and Richard Anderson Drparimem 0/ Physics

Spray and Combustion of Gelled Hypergolic Propellants

DTIC Science & Technology

2014-10-20

Anderson Postdoc tlnu 2/09 Ast:I·ium Mau DeRidder Anderson Postdoc tlnu 5110 Spacex Chenzhou Lian Merkle Postdoc tlnu 8/10 IBM Watson Labs Changjin Yoon...Heister PhD, 1211 1 GE Global Research Center - 5 - - 6 - Erik Dambach Heister/Pourpoint PhD, 5/11 SpaceX Paulo Santos Campanella PhD, 8/11...Yair Solomon Anderson MS, 8/12 Technion Jordan Forness Heister/Pourpoint MS, 5/13 SpaceX Jennifer Mallory Sojka PhD, 5/12 Western New England

5. PHOTOCOPY ADVERTISING VIEW OF THE LAMBERT AUTOCAR WITH CUTAWAY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. PHOTOCOPY ADVERTISING VIEW OF THE LAMBERT AUTOCAR WITH CUTAWAY OF TRANSMISSION, FROM ANDERSON CITY DIRECTORY, CA. 1906-1907 - Buckeye Manufacturing Company, Columbia Avenue, Anderson, Madison County, IN

Robust and Rapid Air-Borne Odor Tracking without Casting1,2,3

PubMed Central

Bhattacharyya, Urvashi

2015-01-01

Abstract Casting behavior (zigzagging across an odor stream) is common in air/liquid-borne odor tracking in open fields; however, terrestrial odor localization often involves path selection in a familiar environment. To study this, we trained rats to run toward an odor source in a multi-choice olfactory arena with near-laminar airflow. We find that rather than casting, rats run directly toward an odor port, and if this is incorrect, they serially sample other sources. This behavior is consistent and accurate in the presence of perturbations, such as novel odors, background odor, unilateral nostril stitching, and turbulence. We developed a model that predicts that this run-and-scan tracking of air-borne odors is faster than casting, provided there are a small number of targets at known locations. Thus, the combination of best-guess target selection with fallback serial sampling provides a rapid and robust strategy for finding odor sources in familiar surroundings. PMID:26665165

Local Tax Limits, Student Achievement, and School-Finance Equalization

ERIC Educational Resources Information Center

Davis, Matthew; Vedder, Andrea; Stone, Joe

2016-01-01

Evidence that local tax and expenditure limits (TELs) for public K-12 schools lower student achievement is widely attributed to the effects of reduced funding, but our results cast doubt on reduced funding as the primary explanation for negative effects of TELs and instead suggest the importance of the predictability of funding. Students in…

Computational studies of model disordered and strongly correlated electronic systems

NASA Astrophysics Data System (ADS)

Johri, Sonika

The theory of non-interacting electrons in perfect crystals was completed soon after the advent of quantum mechanics. Though capable of describing electron behaviour in most simple solid state physics systems, this approach falls woefully short of describing condensed matter systems of interest today, and designing the quantum devices of the future. The reason is that nature is never free of disorder, and emergent properties arising from interactions can be clearly seen in the pure, low-dimensional materials that can be engineered today. In this thesis, I address some salient problems in disordered and correlated electronic systems using modern numerical techniques like sparse matrix diagonalization, density matrix renormalization group (DMRG), and large disorder renormalization group (LDRG) methods. The pioneering work of P. W. Anderson, in 1958, led to an understanding of how an electron can stop diffusing and become localized in a region of space when a crystal is sufficiently disordered. Thus disorder can lead to metal-insulator transitions, for instance, in doped semiconductors. Theoretical research on the Anderson disorder model since then has mostly focused on the localization-delocalization phase transition. The localized phase in itself was not thought to exhibit any interesting physics. Our work has uncovered a new singularity in the disorder-averaged inverse participation ratio of wavefunctions within the localized phase, arising from resonant states. The effects of system size, dimension and disorder distribution on the singularity have been studied. A novel wavefunction-based LDRG technique has been designed for the Anderson model which captures the singular behaviour. While localization is well established for a single electron in a disordered potential, the situation is less clear in the case of many interacting particles. Most studies of a many-body localized phase are restricted to a system which is isolated from its environment. Such a condition cannot be achieved perfectly in experiments. A chapter of this thesis is devoted to studying signatures of incomplete localization in a disordered system with interacting particles which is coupled to a bath. . Strongly interacting particles can also give rise to topological phases of matter that have exotic emergent properties, such as quasiparticles with fractional charges and anyonic, or perhaps even non-Abelian statistics. In addition to their intrinsic novelty, these particles (e.g. Majorana fermions) may be the building blocks of future quantum computers. The third part of my thesis focuses on the best experimentally known realizations of such systems - the fractional quantum Hall effect (FQHE) which occurs in two-dimensional electron gases in a strong perpendicular magnetic field. It has been observed in systems such as semiconductor heterostructures and, more recently, graphene. I have developed software for exact diagonalization of the many-body FQHE problem on the surface of a cylinder, a hitherto unstudied type of geometry. This geometry turns out to be optimal for the DMRG algorithm. Using this new geometry, I have studied properties of various fractionally-filled states, computing the overlap between exact ground states and model wavefunctions, their edge excitations, and entanglement spectra. I have calculated the sizes and tunneling amplitudes of quasiparticles, information which is needed to design the interferometers used to experimentally measure their Aharanov-Bohm phase. I have also designed numerical probes of the recently discovered geometric degree of freedom of FQHE states.

Louisa Garrett Anderson (1873-1943), surgeon and suffragette.

PubMed

Geddes, Jennian F

2008-11-01

Louisa Garrett Anderson, daughter of Britain's first woman doctor, has been largely forgotten today despite the fact that her contribution to the women's movement was as great as that of her mother. Recognized by her contemporaries as an important figure in the suffrage campaign, Anderson chose to lend her support through high-profile action, being one of the few women doctors in her generation who risked their professional as well as their personal reputation in the fight for women's rights by becoming a suffragette - in her case, even going so far as to spend a month in prison for breaking a window on a demonstration. On the outbreak of war, with only the clinical experience she had gained as outpatient surgeon in a women's hospital, Anderson established a series of women-run military hospitals where she was a Chief Surgeon. The most successful was the Endell Street Military Hospital in London, funded by the Royal Army Medical Corps and the only army hospital ever to be run and staffed entirely by women. Believing that a doctor had an obligation to take a lead in public affairs, Anderson continued campaigning for women's issues in the unlikely setting of Endell Street, ensuring that their activities remained in the public eye through constant press coverage. Anderson's achievement was that her work played no small part in expunging the stigma of the militant years in the eyes of the public and - more importantly - was largely instrumental in putting women doctors on equal terms with their male colleagues.

Towards developing Kentucky's landscape change maps

USGS Publications Warehouse

Zourarakis, D.P.; Lambert, S.C.; Palmer, M.

2003-01-01

The Kentucky Landscape Snapshot Project, a NASA-funded project, was established to provide a first baseline land cover/land use map for Kentucky. Through this endeavor, change detection will be institutionalized, thus aiding in decision-making at the local, state, and federal planning levels. 2002 Landsat 7 imaginery was classified following and Anderson Level III scheme, providing an enhancement over the 1992 USGS National Land Cover Data Set. Also as part of the deliverables, imperviousness and canopy closure layers were produced with the aid of IKONOS high resolution, multispectral imagery.

Global and local investigations of the electrochemical behavior the T6 heat treated Mg-Zn-RE magnesium alloy thixo-cast

NASA Astrophysics Data System (ADS)

Szklarz, Zbigniew; Bisztyga, Magdalena; Krawiec, Halina; Lityńska-Dobrzyńska, Lidia; Rogal, Łukasz

2017-05-01

The influence of semi-solid metal processing (SSM called also as thixoforming) of ZE41A magnesium alloy on the electrochemical behavior in 0.1 M NaCl solution was investigated. To describe the corrosion behavior of ZE41A alloy, the electrochemical measurements were conducted in global and local scale for two types of specimens: (1) ingot-feedstock, (2) specimen after thixoforming and T6 treatment. The heat treatment and thixoforming significantly improved mechanical properties of ZE41A alloy. The global corrosion potential is slightly higher for treated sample what is related to the presence of Zr-Zn nanoparticles distributed in solid solution. The corrosion behavior differences between feedstock and thixo-cast after T6 samples are also visible in local scale, what has been revealed by using microcapillary technique. However there is no improvement in corrosion behavior after treatment. Corrosion morphology of the treated sample indicate higher susceptibility to pitting and filiform corrosion. Corrosion rate is also slightly higher.

1. VIEW OF SOUTH (GABLE END) AND WEST WALLS FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. VIEW OF SOUTH (GABLE END) AND WEST WALLS FROM ANDERSON WAY, FACING NORTHEAST. - Fort McPherson, World War II Station Hospital, Nurses' Quarters, Anderson Way & Howe Street, Atlanta, Fulton County, GA

40 CFR 81.344 - Texas.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie... Victoria Area: Victoria County Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable... 022Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass...

40 CFR 81.344 - Texas.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass County...: Victoria County Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment...-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass County...

40 CFR 81.344 - Texas.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass County...: Victoria County Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment... 022Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass...

40 CFR 81.344 - Texas.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass County...: Victoria County Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment... 022Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass...

Dephasing Catastrophe in 4-ε Dimensions: A Possible Instability of the Ergodic (Many-Body-Delocalized) Phase.

PubMed

Liao, Yunxiang; Foster, Matthew S

2018-06-08

In two dimensions, dephasing by a bath cuts off Anderson localization that would otherwise occur at any energy density for fermions with disorder. For an isolated system with short-range interactions, the system can be its own bath, exhibiting diffusive (non-Markovian) thermal density fluctuations. We recast the dephasing of weak localization due to a diffusive bath as a self-interacting polymer loop. We investigate the critical behavior of the loop in d=4-ε dimensions, and find a nontrivial fixed point corresponding to a temperature T^{*}∼ε>0 where the dephasing time diverges. Assuming that this fixed point survives to ε=2, we associate it with a possible instability of the ergodic phase. Our approach may open a new line of attack against the problem of the ergodic to many-body-localized phase transition in d>1 spatial dimensions.

Dephasing Catastrophe in 4 -ɛ Dimensions: A Possible Instability of the Ergodic (Many-Body-Delocalized) Phase

NASA Astrophysics Data System (ADS)

Liao, Yunxiang; Foster, Matthew S.

2018-06-01

In two dimensions, dephasing by a bath cuts off Anderson localization that would otherwise occur at any energy density for fermions with disorder. For an isolated system with short-range interactions, the system can be its own bath, exhibiting diffusive (non-Markovian) thermal density fluctuations. We recast the dephasing of weak localization due to a diffusive bath as a self-interacting polymer loop. We investigate the critical behavior of the loop in d =4 -ɛ dimensions, and find a nontrivial fixed point corresponding to a temperature T*˜ɛ >0 where the dephasing time diverges. Assuming that this fixed point survives to ɛ =2 , we associate it with a possible instability of the ergodic phase. Our approach may open a new line of attack against the problem of the ergodic to many-body-localized phase transition in d >1 spatial dimensions.

Disorder-induced localization in crystalline phase-change materials.

PubMed

Siegrist, T; Jost, P; Volker, H; Woda, M; Merkelbach, P; Schlockermann, C; Wuttig, M

2011-03-01

Localization of charge carriers in crystalline solids has been the subject of numerous investigations over more than half a century. Materials that show a metal-insulator transition without a structural change are therefore of interest. Mechanisms leading to metal-insulator transition include electron correlation (Mott transition) or disorder (Anderson localization), but a clear distinction is difficult. Here we report on a metal-insulator transition on increasing annealing temperature for a group of crystalline phase-change materials, where the metal-insulator transition is due to strong disorder usually associated only with amorphous solids. With pronounced disorder but weak electron correlation, these phase-change materials form an unparalleled quantum state of matter. Their universal electronic behaviour seems to be at the origin of the remarkable reproducibility of the resistance switching that is crucial to their applications in non-volatile-memory devices. Controlling the degree of disorder in crystalline phase-change materials might enable multilevel resistance states in upcoming storage devices.

Dynamics of the one-dimensional Anderson insulator coupled to various bosonic baths

NASA Astrophysics Data System (ADS)

Bonča, Janez; Trugman, Stuart A.; Mierzejewski, Marcin

2018-05-01

We study a particle which propagates in a one-dimensional strong random potential and is coupled to a bosonic bath. We independently test various properties of bosons (hopping term, hard-core effects, and generic boson-boson interaction) and show that bosonic itineracy is the essential ingredient governing the dynamics of the particle. Coupling of the particle to itinerant phonons or hard-core bosons alike leads to delocalization of the particle by virtue of a subdiffusive (or diffusive) spread from the initially localized state. Delocalization remains in effect even when the boson frequency and the bandwidth of itinerant bosons remain an order of magnitude smaller than the magnitude of the random potential. When the particle is coupled to localized bosons, its spread remains logarithmic or even sublogarithmic. The latter result together with the survival probability shows that the particle remains localized despite being coupled to bosons.

Optimization of Squeeze Casting for Aluminum Alloy Parts

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

David Schwam; John F. Wallace; Qingming Chang

2002-07-30

This study was initiated with the installation of a new production size UBE 350 Ton VSC Squeeze Casting system in the Metal Casting Laboratory at Case Western University. A Lindberg 75k W electrical melting furnace was installed alongside. The challenge of installation and operation of such industrial-size equipment in an academic environment was met successfully. Subsequently, a Sterling oil die heater and a Visi-Track shot monitoring system were added. A significant number of inserts were designed and fabricated over the span of the project, primarily for squeeze casting different configurations of test bars and plates. A spiral ''ribbon insert'' formore » evaluation of molten metal fluidity was also fabricated. These inserts were used to generate a broad range of processing conditions and determine their effect on the quality of the squeeze cast parts. This investigation has studied the influence of the various casting variables on the quality of indirect squeeze castings primarily of aluminum alloys. The variables studied include gating design, fill time and fill patter, metal pressure and die temperature variations. The quality of the die casting was assessed by an analysis of both their surface condition and internal soundness. The primary metal tested was an aluminum 356 alloy. In addition to determining the effect of these casting variables on casting quality as measured by a flat plate die of various thickness, a number of test bar inserts with different gating designs have been inserted in the squeeze casting machine. The mechanical properties of these test bars produced under different squeeze casting conditions were measured and reported. The investigation of the resulting properties also included an analysis of the microstructure of the squeeze castings and the effect of the various structural constituents on the resulting properties. The main conclusions from this investigation are as follows: The ingate size and shape are very important since it must remain open until the casting is solidified and pressure is maintained on the solidifying casting. Fanned gates, particularly on the smaller section castings avoid jetting effects at the ingate end. The fan type ingate helps accomplish a rapid fill without high velocities. The molten metal has to fill the cavity before localized solidification occurs. This is best accomplished with a larger ingate to attain rapid filling without excessive velocity or jetting that occurs at high metal velocities. Straight gates are prone to case jetting of the metal stream even a low velocities. Fanned gates allow use of higher fill velocity without excessive jetting. A higher metal pressure provides a more complete fill of the die including improved compensation for solidification shrinkage. With the proper filling pattern, ingates, overflows and die temperature for a given die, very good tensile properties can be attained in squeeze casting. In general, the smaller squeeze castings require higher die temperatures. Computer models using the UES Procast and MagmaSoft finite element software can, after suitable adjustments, predict the flow pattern in the die cavity.« less

Quantum criticality of the two-channel pseudogap Anderson model: universal scaling in linear and non-linear conductance.

PubMed

Wu, Tsan-Pei; Wang, Xiao-Qun; Guo, Guang-Yu; Anders, Frithjof; Chung, Chung-Hou

2016-05-05

The quantum criticality of the two-lead two-channel pseudogap Anderson impurity model is studied. Based on the non-crossing approximation (NCA) and numerical renormalization group (NRG) approaches, we calculate both the linear and nonlinear conductance of the model at finite temperatures with a voltage bias and a power-law vanishing conduction electron density of states, ρc(ω) proportional |ω − μF|(r) (0 < r < 1) near the Fermi energy μF. At a fixed lead-impurity hybridization, a quantum phase transition from the two-channel Kondo (2CK) to the local moment (LM) phase is observed with increasing r from r = 0 to r = rc < 1. Surprisingly, in the 2CK phase, different power-law scalings from the well-known [Formula: see text] or [Formula: see text] form is found. Moreover, novel power-law scalings in conductances at the 2CK-LM quantum critical point are identified. Clear distinctions are found on the critical exponents between linear and non-linear conductance at criticality. The implications of these two distinct quantum critical properties for the non-equilibrium quantum criticality in general are discussed.

Mixed valent metals

NASA Astrophysics Data System (ADS)

Riseborough, P. S.; Lawrence, J. M.

2016-08-01

We review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effect and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger’s theorem, the Friedel sum rule, the Schrieffer-Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Noziéres exhaustion principle, Doniach’s diagram, the Anderson lattice model, the Slave-Boson method, etc.

Mixed valent metals

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

Riseborough, P. S.; Lawrence, Jon M.

Here, we review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effectmore » and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger's theorem, the Friedel sum rule, the Schrieffer–Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Nozieres exhaustion principle, Doniach's diagram, the Anderson lattice model, the Slave-Boson method, etc.« less

Mixed valent metals

DOE PAGES

Riseborough, P. S.; Lawrence, Jon M.

2016-07-04

Here, we review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effectmore » and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger's theorem, the Friedel sum rule, the Schrieffer–Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Nozieres exhaustion principle, Doniach's diagram, the Anderson lattice model, the Slave-Boson method, etc.« less

1. VIEW OF BUILDING 128: SOUTH (GABLE END) AND WEST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. VIEW OF BUILDING 128: SOUTH (GABLE END) AND WEST SIDES FROM ANDERSON WAY, FACING NORTHEAST. - Fort McPherson, World War II Station Hospital, Hospital Wards, Anderson Way & Howe Street, Atlanta, Fulton County, GA

1. VIEW OF WEST (GABLE END) AND SOUTH SIDES, FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. VIEW OF WEST (GABLE END) AND SOUTH SIDES, FROM WEST END OF ANDERSON WAY FACING NORTHEAST. - Fort McPherson, World War II Station Hospital, Mess Hall, Anderson Way & Howe Street, Atlanta, Fulton County, GA

Anderson during a MSG Leak Test in the US Lab during Expedition 15

NASA Image and Video Library

2007-06-28

ISS015-E-14705 (28 June 2007) --- Astronaut Clayton C. Anderson, Expedition 15 flight engineer, works with the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station.

Ballistic Missile Early Warning System Clear Air Force Station, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Ballistic Missile Early Warning System - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

40 CFR 81.344 - Texas.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass County... Victoria Area: Victoria County Attainment AQCR 022 Shreveport-Texarkana-Tyler Interstate Unclassifiable... 022Shreveport-Texarkana-Tyler Interstate Unclassifiable/Attainment Anderson County Bowie County Camp County Cass...

Local magnitude scale for Valle Medio del Magdalena region, Colombia

NASA Astrophysics Data System (ADS)

Londoño, John Makario; Romero, Jaime A.

2017-12-01

A local Magnitude (ML) scale for Valle Medio del Magdalena (VMM) region was defined by using 514 high quality earthquakes located at VMM area and inversion of 2797 amplitude values of horizontal components of 17 stations seismic broad band stations, simulated in a Wood-Anderson seismograph. The derived local magnitude scale for VMM region was: ML =log(A) + 1.3744 ∗ log(r) + 0.0014776 ∗ r - 2.397 + S Where A is the zero-to-peak amplitude in nm in horizontal components, r is the hypocentral distance in km, and S is the station correction. Higher values of ML were obtained for VMM region compared with those obtained with the current formula used for ML determination, and with California formula. With this new scale ML values are adjusted to local conditions beneath VMM region leading to more realistic ML values. Moreover, with this new ML scale the seismicity caused by tectonic or fracking activity at VMM region can be monitored more accurately.

Shadows on Ice

NASA Image and Video Library

2007-01-17

Canyons and mountain peaks snake along the terminator on the crater-covered, icy moon Dione. With the Sun at a low angle on their local horizon, the line of mountain ridges above center casts shadows toward the east

JILA BEC/Ultracold Atoms Homepage

Science.gov Websites

JILA BEC & Ultracold Atoms Bose Einstein Condensate Eric Cornell Cornell Group Debbie Jin Jin Group Jun Ye Ye Group Dana Anderson Anderson Group What is BEC? Easy BEC Machine Nobel BEC BibTek Papers

75 FR 42611 - Energy Conservation Program for Consumer Products: Test Procedure for Microwave Ovens

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

... visiting the Resource Room. FOR FURTHER INFORMATION CONTACT: Mr. Wes Anderson, U.S. Department of Energy..., SW., Washington, DC 20585- 0121. Tel.: (202) 586-7335. E-mail: Wes.Anderson@ee.doe.gov . Ms...

Educational Leadership. [SITE 2001 Section].

ERIC Educational Resources Information Center

Tollett, John R., Ed.

This document contains the following papers on educational leadership from the SITE (Society for Information Technology & Teacher Education) 2001 conference: "Electronic Curriculum Development and Assessment" (Kevin M. Anderson and Cindy L. Anderson); "The Dilemma of Teacher Training" (Alfred Bork); "Technology and…

Alaskan Air Defense and Early Warning Systems Clear Air ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Alaskan Air Defense and Early Warning Systems - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Implementation and Validation of 3-D Ice Accretion Measurement Methodology

NASA Technical Reports Server (NTRS)

Lee, Sam; Broeren, Andy P.; Kreeger, Richard E.; Potapczuk, Mark; Utt, Lloyd

2014-01-01

A research program has been implemented to develop and validate the use of a commercial 3-D laser scanning system to record ice accretion geometry in the NASA Icing Research Tunnel. A main component of the program was the geometric assessment of the 3- D laser scanning system on a 2-D (straight wing) and a 3-D (swept wing) airfoil geometries. This exercise consisted of comparison of scanned ice accretion to castings of the same ice accretion. The scan data were also used to create rapid prototype artificial ice shapes that were scanned and compared to the original ice accretion. The results from geometric comparisons on the straight wing showed that the ice shape models generated through the scan/rapid prototype process compared reasonably well with the cast shapes. Similar results were obtained with the geometric comparisons on the swept wing. It was difficult to precisely compare the scans of the cast shapes to the original ice accretion scans because the cast shapes appear to have shrunk during the mold/casting process by as much as 0.10-inch. However the comparison of the local ice-shape features were possible and produced better results. The rapid prototype manufacturing process was shown to reproduce the original ice accretion scan normally within 0.01-inch.

Effect of Porosity on Deformation, Damage, and Fracture of Cast Steel

NASA Astrophysics Data System (ADS)

Hardin, R. A.; Beckermann, C.

2013-12-01

A combined experimental and computational study is performed to investigate the effect of centerline shrinkage porosity on deformation, damage, and fracture of cast steel under tensile testing. Steel plates containing shrinkage porosity are cast in sand molds, machined into test coupons, and tensile tested to fracture. The average volumetric porosity in the gage section of the specimens with porosity ranges from 0.10 to 0.27 pct. Ductility in the test castings with porosity is markedly reduced with the percent elongation data ranging from 12.8 to 19.6 pct; vs 22 pct elongation for the sound material. Radiographic imaging is used to measure and reconstruct the porosity field in the test specimens. The reconstructed porosity field is then used in a finite-element stress analysis simulating the tensile testing. Local elastic properties are reduced according to the porosity fraction present. Porous metal plasticity theory is used to model the damage due to porosity and the fracture. Good agreement is obtained between the measured and predicted stress-strain curves and fracture behaviors. The reduction in ductility is predicted well by comparing the measured and the simulated elongations. The computational modeling approach used in this study allows for a detailed evaluation of the effect of porosity, including its size, shape, and location, on the fracture behavior of steel castings.

Anderson and water bubble

NASA Image and Video Library

2010-04-12

S131-E-009277 (12 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, watches a water bubble float freely between him and the camera, showing his image refracted, on the middeck of space shuttle Discovery while docked with the International Space Station.

Anderson and water bubble

NASA Image and Video Library

2010-04-12

S131-E-009299 (12 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, watches a water bubble float freely between him and the camera, showing his image refracted, on the middeck of space shuttle Discovery while docked with the International Space Station.

Carl Anderson and the Discovery of the Positron

Science.gov Websites

experimental piece of equipment of choice to study cosmic rays. ... Anderson designed and built his own cloud ? Top Some links on this page may take you to non-federal websites. Their policies may differ from this

Program Spotlight: UPR and MD Anderson Partnership Welcomes Its First Graduates

Cancer.gov

CRCHD joins the PIs and Diversity Training co-leaders of the Univ. of Puerto Rico and the Univ. of Texas MD Anderson Cancer Center U54 Partnership for Excellence in Cancer Research in congratulating its first graduates.

76 FR 30555 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Central Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-26

[email protected] . FOR FURTHER INFORMATION CONTACT: Mr. Wes Anderson, U.S. Department of Energy, Office... Avenue, SW., Washington, DC 20585-0121. Telephone: (202) 586-7335. E-mail: Wes.Anderson@ee.doe.gov . Ms...

76 FR 39245 - Energy Conservation Program: Energy Conservation Standards for Residential Furnaces and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... Wes.Anderson@ee.doe.gov . Mr. Eric Stas or Ms. Jennifer Tiedeman, U.S. Department of Energy, Office of.... Wesley Anderson (central air conditioners and heat pumps), U.S. Department of Energy, Office of Energy...

A Brief History of Thoracic Surgery at the University of Texas MD Anderson Cancer Center.

PubMed

Walsh, Garrett Lyndon; Mehran, Reza John

2016-01-01

This article describes the history of the creation of the Department of Thoracic Surgery at the University of Texas MD Anderson Cancer Center in Houston, Texas. Copyright © 2016 Elsevier Inc. All rights reserved.

Detection of Anderson-Fabry cardiomyopathy with CMR in a patient with chest pain and elevated cardiac biomarkers.

PubMed

Albin, Glenn; Ryan, Michael; Heltne, Carl

2006-01-01

This case illustrates the utility of CMR in evaluating a patient with undiagnosed Anderson-Fabry disease who presented with chest pain, elevated cardiac biomarkers, normal coronary arteries, and an abnormal echocardiogram.

KSC-03PD-2976

NASA Technical Reports Server (NTRS)

2003-01-01

KENNEDY SPACE CENTER, FLA. -- Sandra Anderson, wife of STS-107 Payload Commander Michael Anderson, visits a new residence hall at the Florida Institute of Technology (FIT) in Melbourne, Fla., named for her late husband. Family members of the STS-107 astronauts, other dignitaries, members of the university community and the public gathered for a dedication ceremony for the Columbia Village at FIT. Each of the seven new residence halls in the complex is named for one of the STS-107 astronauts who perished during the Columbia accident -- Rick Husband, Willie McCool, Laurel Clark, Michael Anderson, David Brown, Kalpana Chawla, and Ilan Ramon.

Interaction effect in the Kondo energy of the periodic Anderson-Hubbard model

NASA Astrophysics Data System (ADS)

Itai, K.; Fazekas, P.

1996-07-01

We extend the periodic Anderson model by switching on a Hubbard U for the conduction band. The nearly integral valent limit of the Anderson-Hubbard model is studied with the Gutzwiller variational method. The lattice Kondo energy shows U dependence both in the prefactor and the exponent. Switching on U reduces the Kondo scale, which can be understood to result from the blocking of hybridization. At half filling, we find a Brinkman-Rice-type transition from a Kondo insulator to a Mott insulator. Our findings should be relevant for a number of correlated two-band models of recent interest.

Kondo dynamics of quasiparticle tunneling in a two-reservoir Anderson model.

PubMed

Hong, Jongbae

2011-07-13

We study the Kondo dynamics in a two-reservoir Anderson impurity model in which quasiparticle tunneling occurs between two reservoirs. We show that singlet hopping is an essential component of Kondo dynamics in the quasiparticle tunneling. We prove that two resonant tunneling levels exist in the two-reservoir Anderson impurity model and the quasiparticle tunnels through one of these levels when a bias is applied. The Kondo dynamics is explained by obtaining the retarded Green's function. We obtain the analytic expressions of the spectral weights of coherent peaks by analyzing the Green's function at the atomic limit.

Abrupt physical and chemical changes during 1992-1999, Anderson Springs, SE Geyser Geothermal Field, California

USGS Publications Warehouse

Janik, Cathy J.; Goff, Fraser; Walter, Stephen R.; Sorey, Michael L.; Counce, Dale; Colvard, Elizabeth M.

2000-01-01

The Anderson Springs area is located about 90 miles (145 kilometers) north of San Francisco, California, in the southwestern part of Lake County. The area was first developed in the late 1800s as a health resort, which was active until the 1930s. Patrons drank a variety of cool to hot mineral waters from improved springs, swam in various baths and pools, and hiked in the rugged hills flanking Anderson Creek and its tributaries. In the bluffs to the south of the resort were four small mercury mines of the eastern Mayacmas quicksilver district. About 1,260 flasks of mercury were produced from these mines between 1909 and 1943. By the early 1970s, the higher ridges south and west of Anderson Springs became part of the southeast sector of the greater Geysers geothermal field. Today, several electric power plants are built on these ridges, producing energy from a vapor-dominated 240 °C reservoir. Only the main hot spring at Anderson Springs has maintained a recognizable identity since the 1930s. The hot spring is actually a cluster of seeps and springs that issue from a small fault in a ravine southwest of Anderson Creek. Published and unpublished records show that the maximum temperature (Tm) of this cluster fell gradually from 63°C in 1889 to 48°C in 1992. However, Tm of the cluster climbed to 77°C in 1995 and neared boiling (98°C) in 1998. A new cluster of boiling vents and small fumaroles (Tm = 99.3°C) formed in 1998 about 30 m north of the old spring cluster. Several evergreen trees on steep slopes immediately above these vents apparently were killed by the new activity. Thermal waters at Anderson Hot Springs are mostly composed of near-surface ground waters with some added gases and condensed steam from The Geysers geothermal system. Compared to gas samples from Southeast Geysers wells, the hot spring gases are higher in CO2 and lower in H2S and NH3. As the springs increased in temperature, however, the gas composition became more like the mean composition of steam discharges from the Southeast Geysers. The hot spring waters are low in ions of Cl, B, and Li, but relatively high in HCO3, SO4 and NH4. The stable-isotope compositions (deuterium and oxygen-18) of these waters plot near the global meteoric water line. Geochemical data through time reveal apparent maxima in the concentrations of SO4, Fe, and Mn in 1991 to 1992, before the cluster became hotter. The black-to-gray deposits from the new spring cluster are rich in pyrite and contain anomalous metals. About one-half mile to the east of the hot springs, mineralized water discharges intermittently from an old adit of the Schwartz (Anderson) mine, and enters a tributary of Anderson Creek. This drainage increased substantially in July 1998, and a slurry of mine water and precipitates were transported down the tributary and into Anderson Creek. In December 1998, the adit water was 22°C, and had a chemical composition that was similar to spring waters that once discharged in the ravines surrounding the old Anderson Springs resort. The cause for the abrupt changes that have occurred in thermal features at Anderson Springs is still not resolved. One possibility is that these changes are a response to withdrawal of steam from The Geysers geothermal field over more than 20 years of production. Pressure declines in the geothermal reservoir may have caused a "drying out" of the overlying condensation zone. Induced boiling in this zone and upflow of deep steam to shallower depths would cause heating and vaporization of shallow ground waters. In addition, earthquakes occurring in the vicinity of Anderson Springs have increased significantly after nearby geothermal power plants began operation. These earthquakes may have enhanced surface discharge of thermal fluids along fractures and faults.

In vitro degradation of ZM21 magnesium alloy in simulated body fluids.

PubMed

Witecka, Agnieszka; Bogucka, Aleksandra; Yamamoto, Akiko; Máthis, Kristián; Krajňák, Tomáš; Jaroszewicz, Jakub; Święszkowski, Wojciech

2016-08-01

In vitro degradation behavior of squeeze cast (CAST) and equal channel angular pressed (ECAP) ZM21 magnesium alloy (2.0wt% Zn-0.98wt% Mn) was studied using immersion tests up to 4w in three different biological environments. Hanks' Balanced Salt Solution (Hanks), Earle's Balanced Salt Solution (Earle) and Eagle minimum essential medium supplemented with 10% (v/v) fetal bovine serum (E-MEM+10% FBS) were used to investigate the effect of carbonate buffer system, organic compounds and material processing on the degradation behavior of the ZM21 alloy samples. Corrosion rate of the samples was evaluated by their Mg(2+) ion release, weight loss and volume loss. In the first 24h, the corrosion rate sequence of the CAST samples was as following: Hanks>E-MEM+10% FBS>Earle. However, in longer immersion periods, the corrosion rate sequence was Earle>E-MEM+10% FBS≥Hanks. Strong buffering effect provided by carbonate buffer system helped to maintain the pH avoiding drastic increase of the corrosion rate of ZM21 in the initial stage of immersion. Organic compounds also contributed to maintain the pH of the fluid. Moreover, they adsorbed on the sample surface and formed an additional barrier on the insoluble salt layer, which was effective to retard the corrosion of CAST samples. In case of ECAP, however, this effect was overcome by the occurrence of strong localized corrosion due to the lower pH of the medium. Corrosion of ECAP samples was much greater than that of CAST, especially in Hanks, due to higher sensitivity of ECAP to localized corrosion and the presence of Cl(-). The present work demonstrates the importance of using an appropriate solution for a reliable estimation of the degradation rate of Mg-base degradable implants in biological environments, and concludes that the most appropriate solution for this purpose is E-MEM+10% FBS, which has the closest chemical composition to human blood plasma. Copyright © 2016 Elsevier B.V. All rights reserved.

Many-body localization proximity effects in platforms of coupled spins and bosons

NASA Astrophysics Data System (ADS)

Marino, J.; Nandkishore, R. M.

2018-02-01

We discuss the onset of many-body localization in a one-dimensional system composed of a XXZ quantum spin chain and a Bose-Hubbard model linearly coupled together. We consider two complementary setups, depending whether spatial disorder is initially imprinted on spins or on bosons; in both cases, we explore the conditions for the disordered portion of the system to localize by proximity of the other clean half. Assuming that the dynamics of one of the two parts develops on shorter time scales than the other, we can adiabatically eliminate the fast degrees of freedom, and derive an effective Hamiltonian for the system's remainder using projection operator techniques. Performing a locator expansion on the strength of the many-body interaction term or on the hopping amplitude of the effective Hamiltonian thus derived, we present results on the stability of the many-body localized phases induced by proximity effect. We also briefly comment on the feasibility of the proposed model through modern quantum optics architectures, with the long-term perspective to realize experimentally, in composite open systems, Anderson or many-body localization proximity effects.

Metadisorder for designer light in random systems

PubMed Central

Yu, Sunkyu; Piao, Xianji; Hong, Jiho; Park, Namkyoo

2016-01-01

Disorder plays a critical role in signal transport by controlling the correlation of a system, as demonstrated in various complex networks. In wave physics, disordered potentials suppress wave transport, because of their localized eigenstates, from the interference between multiple scattering paths. Although the variation of localization with tunable disorder has been intensively studied as a bridge between ordered and disordered media, the general trend of disorder-enhanced localization has remained unchanged, and the existence of complete delocalization in highly disordered potentials has not been explored. We propose the concept of “metadisorder”: randomly coupled optical systems in which eigenstates can be engineered to achieve unusual localization. We demonstrate that one of the eigenstates in a randomly coupled system can always be arbitrarily molded, regardless of the degree of disorder, by adjusting the self-energy of each element. Ordered waves with the desired form are then achieved in randomly coupled systems, including plane waves and globally collective resonances. We also devise counterintuitive functionalities in disordered systems, such as “small-world–like” transport from non–Anderson-type localization, phase-conserving disorder, and phase-controlled beam steering. PMID:27757414

Exploring Localization in Nuclear Spin Chains

NASA Astrophysics Data System (ADS)

Wei, Ken Xuan; Ramanathan, Chandrasekhar; Cappellaro, Paola

2018-02-01

Characterizing out-of-equilibrium many-body dynamics is a complex but crucial task for quantum applications and understanding fundamental phenomena. A central question is the role of localization in quenching thermalization in many-body systems and whether such localization survives in the presence of interactions. Probing this question in real systems necessitates the development of an experimentally measurable metric that can distinguish between different types of localization. While it is known that the localized phase of interacting systems [many-body localization (MBL)] exhibits a long-time logarithmic growth in entanglement entropy that distinguishes it from the noninteracting case of Anderson localization (AL), entanglement entropy is difficult to measure experimentally. Here, we present a novel correlation metric, capable of distinguishing MBL from AL in high-temperature spin systems. We demonstrate the use of this metric to detect localization in a natural solid-state spin system using nuclear magnetic resonance (NMR). We engineer the natural Hamiltonian to controllably introduce disorder and interactions, and observe the emergence of localization. In particular, while our correlation metric saturates for AL, it slowly keeps increasing for MBL, demonstrating analogous features to entanglement entropy, as we show in simulations. Our results show that our NMR techniques, akin to measuring out-of-time correlations, are well suited for studying localization in spin systems.

76 FR 59416 - Senior Executive Service Performance Review Board

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-26

... Anderson, Gary Anderson, Penny Andrews, John Armstrong, Charles R. Armstrong, Sue Athmann, Ronald Ayala, Janice Barber, Delores Baroukh, Nader Bartoldus, Charles Bathurst, Donald Bauhs, Kim Beagles, James... Butcher, Michael Button, Christopher Byrne, Michael Byrne, Sean J. Cahill, Donna L. Callahan, Mary Ellen...

10. VIEW OF SITE B FROM WEST END OF ANDERSON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. VIEW OF SITE B FROM WEST END OF ANDERSON WAY, FACING NORTHEAST (BUILDINGS 131, 130, 129, and 128 ARE VISIBLE.) - Fort McPherson, World War II Station Hospital, Structures, Bordered by Hardee & Thorne Avenues & Howe Street, Atlanta, Fulton County, GA

Spectral density method to Anderson-Holstein model

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

Chebrolu, Narasimha Raju, E-mail: narasimharaju.phy@gmail.com; Chatterjee, Ashok

Two-parameter spectral density function of a magnetic impurity electron in a non-magnetic metal is calculated within the framework of the Anderson-Holstein model using the spectral density approximation method. The effect of electron-phonon interaction on the spectral function is investigated.

Preserved Crevasse Casts in the Whales Deep Basin, eastern Ross Sea

NASA Astrophysics Data System (ADS)

Bart, P. J.; Tulaczyk, S. M.

2017-12-01

A recent seismic stratigraphic study showed that the large bathymetric saddle in the Whales Deep Basin in eastern Ross Sea is a compound grounding zone wedge (CGZW). The basin was occupied by the paleo Bindschadler Ice Stream when grounded ice advanced to the outer continental shelf during the last glacial maximum (LGM). The CGZW is composed of at least seven overlapping GZWs. The crest of the bathymetric saddle corresponds to the grounding zone of GZW7, i.e., the seventh GZW. The north face of the saddle is essentially equivalent to the GZW7 foreset and the south side of the saddle is the GZW7 topset, i.e., the seafloor surface to which the paleo Bindschadler Ice Stream was grounded. The GZW7 topset is mantled by a series of relatively small-amplitude, but very long, ridges with low sinuosity. These ridges were previously imaged by Mosola and Anderson (2006). Here we show a larger-area multibeam survey that was acquired in 2015 during expedition NBP1502B. The larger-area multibeam survey shows that the ridges have amplitudes ranging from 2 to 11 m above grade and have an overall northeast-southwest orientation over an area of at least 500 km2 on the central and western flank of Whales Deep Basin middle continental shelf in water depths ranging from 500 to 550 m. The ridges have spacing that mostly range between 1 and 2 km. The longest ridges are observed to be 40 km. The ridges in the center of the trough have flatter tops than those in the shallower water on the flank of Houtz Bank. In our ongoing investigation of these interesting features, we hypothesize that the ridges formed below a rapidly flowing ice stream as it thinned and was decoupling from the bed towards the end of GZW7 deposition. High ice deformation rates accompanying this process caused the development of large basal crevasses or ice shelf rifts that reached the seafloor. Subglacial till was scraped and collected into lower parts of these crevasses/rifts. Chronologic data indicates that these crevasse casts formed during rapid sea-level rise at 11.5 kyr BP, i.e., during MWP1B, which partly explains their amazing preservation. These casts suggest abrupt ice thinning and bed decoupling during deglaciation of the area.

Special Needs. [SITE 2002 Section].

ERIC Educational Resources Information Center

2002

This document contains the following papers on special needs from the SITE (Society for Information Technology & Teacher Education) 2002 conference: (1) "Selected Technology-Infused Thematic Activities for Elementary and Special Education Teacher Education Programs" (Cindy L. Anderson and Kevin M. Anderson); (2) "Educational IT: How Students and…

40 CFR 81.343 - Tennessee.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Johnson County X That portion of Knox County within a section of downtown Knoxville X Rest of Knox County.... Knoxville, TN: Anderson County This action is effective 3/8/2011 Attainment Blount County This action is.... Knoxville, TN: Anderson County Nonattainment. Blount County Nonattainment. Knox County Nonattainment. Loudon...

19. View of satcom communication dome with TR radome in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. View of satcom communication dome with TR radome in background right. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

9. VIEW OF SITE B FROM EAST END OF ANDERSON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. VIEW OF SITE B FROM EAST END OF ANDERSON WAY, FACING WEST (BUILDINGS 126, 128, 129, 130, and 131 ARE VISIBLE.) - Fort McPherson, World War II Station Hospital, Structures, Bordered by Hardee & Thorne Avenues & Howe Street, Atlanta, Fulton County, GA

41 CFR 109-40.5100 - Scope of subpart.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., AND MOTOR VEHICLES 40-TRANSPORTATION AND TRAFFIC MANAGEMENT 40.51-Price-Anderson Coverage Certifications for Nuclear Shipments § 109-40.5100 Scope of subpart. This subpart sets forth the policy for issuance of certifications regarding Price-Anderson coverage of particular shipments of nuclear materials. ...

Random Matrix Theory and the Anderson Model

NASA Astrophysics Data System (ADS)

Bellissard, Jean

2004-08-01

This paper is devoted to a discussion of possible strategies to prove rigorously the existence of a metal-insulator Anderson transition for the Anderson model in dimension d≥3. The possible criterions used to define such a transition are presented. It is argued that at low disorder the lowest order in perturbation theory is described by a random matrix model. Various simplified versions for which rigorous results have been obtained in the past are discussed. It includes a free probability approach, the Wegner n-orbital model and a class of models proposed by Disertori, Pinson, and Spencer, Comm. Math. Phys. 232:83-124 (2002). At last a recent work by Magnen, Rivasseau, and the author, Markov Process and Related Fields 9:261-278 (2003) is summarized: it gives a toy modeldescribing the lowest order approximation of Anderson model and it is proved that, for d=2, its density of states is given by the semicircle distribution. A short discussion of its extension to d≥3 follows.

Mott glass from localization and confinement

NASA Astrophysics Data System (ADS)

Chou, Yang-Zhi; Nandkishore, Rahul M.; Radzihovsky, Leo

2018-05-01

We study a system of fermions in one spatial dimension with linearly confining interactions and short-range disorder. We focus on the zero-temperature properties of this system, which we characterize using bosonization and the Gaussian variational method. We compute the static compressibility and ac conductivity, and thereby demonstrate that the system is incompressible, but exhibits gapless optical conductivity. This corresponds to a "Mott glass" state, distinct from an Anderson and a fully gapped Mott insulator, arising due to the interplay of disorder and charge confinement. We argue that this Mott glass phenomenology should persist to nonzero temperatures.

Non-Fermi Liquid Behavior in the Single-Impurity Mixed Valence Problem

NASA Astrophysics Data System (ADS)

Zhang, Guang-Ming; Su, Zhao-Bin; Yu, Lu

An effective Hamiltonian of the Anderson single-impurity model with finite-range Coulomb interactions is derived near a particular limit, which is analogous to the Toulouse limit of the ordinary Kondo problem, and the physical properties around the mixed valence quantum critical point are calculated. At this quantum critical point, the local moment is only partially quenched and X-ray edge singularities are exhibited. Around this point, a new type of non-Fermi liquid behavior is predicted with an extra specific heat Cimp ~ T1/4 + AT ln T and spin-susceptibility χimp ~T-3/4 + B ln T.

Mechanical and Microstructural Effects of Thermal Aging on Cast Duplex Stainless Steels by Experiment and Finite Element Method

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

Schwarm, Samuel C.; Mburu, Sarah N.; Kolli, Ratna P.

Cast duplex stainless steel piping in light water nuclear reactors expe- rience thermal aging embrittlement during operational service. Interest in extending the operational life to 80 years requires an increased understanding of the microstructural evolution and corresponding changes in mechanical behavior. We analyze the evolution of the microstructure during thermal aging of cast CF-3 and CF-8 stainless steels using electron microscopy and atom probe tomography. The evolution of the mechanical properties is measured concurrently by mechanical methods such as tensile tests, Charpy V-notch tests, and instrumented nanoinden- tation. A microstructure-based finite element method model is developed and uti- lized inmore » conjunction with the characterization results in order to correlate the local stress-strain effects in the microstructure with the bulk measurements. This work is supported by the DOE Nuclear Energy University Programs (NEUP), contract number DE-NE0000724.« less

Quantitative Experimental Study of Defects Induced by Process Parameters in the High-Pressure Die Cast Process

NASA Astrophysics Data System (ADS)

Sharifi, P.; Jamali, J.; Sadayappan, K.; Wood, J. T.

2018-05-01

A quantitative experimental study of the effects of process parameters on the formation of defects during solidification of high-pressure die cast magnesium alloy components is presented. The parameters studied are slow-stage velocity, fast-stage velocity, intensification pressure, and die temperature. The amount of various defects are quantitatively characterized. Multiple runs of the commercial casting simulation package, ProCAST™, are used to model the mold-filling and solidification events. Several locations in the component including knit lines, last-to-fill region, and last-to-solidify region are identified as the critical regions that have a high concentration of defects. The area fractions of total porosity, shrinkage porosity, gas porosity, and externally solidified grains are separately measured. This study shows that the process parameters, fluid flow and local solidification conditions, play major roles in the formation of defects during HPDC process.

40 CFR 81.343 - Tennessee.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Johnson County X That portion of Knox County within a section of downtown Knoxville X Rest of Knox County... County (2) Attainment. Knoxville, TN: Anderson County This action is effective 3/8/2011 Attainment Blount... Date 1 Type Knoxville, TN: 2 Nonattainment Marginal. Anderson County (part) 2000 Census tracts: 202...

FE Anderson exercising on the CEVIS during STS-118/Expedition 15 Joint Operations

NASA Image and Video Library

2007-08-16

S118-E-07657 (16 Aug. 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station while Space Shuttle Endeavour remains docked with the station.

CEBAS - MS Anderson works with three middeck payloads

NASA Image and Video Library

1998-03-03

S89-E-5204 (25 Jan 1998) --- This Electronic Still Camera (ESC) image shows astronaut Michael P. Anderson, mission specialist, checking the Biotechnology Refrigerator (BTR) while transferring logistics, onboard the Space Shuttle Endeavour. This ESC view was taken on January 25, 1998, at 18:54:53 GMT.

MS Anderson works with three middeck payloads

NASA Image and Video Library

1998-03-03

S89-E-5207 (25 Jan 1998) --- This Electronic Still Camera (ESC) image shows astronaut Michael P. Anderson, mission specialist, checking the Biotechnology Refrigerator (BTR) while transferring logistics onboard the Space Shuttle Endeavour. This ESC view was taken on January 25, 1998, at 18:56:29 GMT.

56. Building 105, close view of ion return RF balance ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

56. Building 105, close view of ion return RF balance tube adjustment controls. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

45. Building 102, view of waveguide "coaxial waste load" device ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

45. Building 102, view of waveguide "coaxial waste load" device connected to waveguide combiner. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Anderson v. University of Wisconsin: Handicap and Race Discrimination in Readmission Procedures.

ERIC Educational Resources Information Center

Smith, Elizabeth R.

1989-01-01

"Anderson v. University of Wisconsin" gives important guidance to universities by detailing the components of race and handicap discrimination claims, and illustrating how these claims can succeed. Readmission procedures that could reduce the likelihood of charges of discrimination are suggested. (Author/MLW)

78. View of radar systems technical publication library, transmitter building ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

78. View of radar systems technical publication library, transmitter building no. 102, second floor. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Adivasis (Original Dwellers) "in the Way of" State-Corporate Development: Development Dispossession and Learning in Social Action for Land and Forests in India

ERIC Educational Resources Information Center

Kapoor, Dip

2009-01-01

This paper traces the kinds of learning engendered through Adivasi trans-local and local subaltern social movement (SSM) action addressing state-corporate developmental collusions, state-caste interests and the resulting dispossession of Adivasis from land, forest and their ways of life given the economic liberalization drive to exploit resources…

Qualitative breakdown of the noncrossing approximation for the symmetric one-channel Anderson impurity model at all temperatures

NASA Astrophysics Data System (ADS)

Sposetti, C. N.; Manuel, L. O.; Roura-Bas, P.

2016-08-01

The Anderson impurity model is studied by means of the self-consistent hybridization expansions in its noncrossing (NCA) and one-crossing (OCA) approximations. We have found that for the one-channel spin-1 /2 particle-hole symmetric Anderson model, the NCA results are qualitatively wrong for any temperature, even when the approximation gives the exact threshold exponents of the ionic states. Actually, the NCA solution describes an overscreened Kondo effect, because it is the same as for the two-channel infinite-U single-level Anderson model. We explicitly show that the NCA is unable to distinguish between these two very different physical systems, independently of temperature. Using the impurity entropy as an example, we show that the low-temperature values of the NCA entropy for the symmetric case yield the limit Simp(T =0 ) →ln√{2 }, which corresponds to the zero temperature entropy of the overscreened Kondo model. Similar pathologies are predicted for any other thermodynamic property. On the other hand, we have found that the OCA approach lifts the artificial mapping between the models and restores correct properties of the ground state, for instance, a vanishing entropy at low enough temperatures Simp(T =0 ) →0 . Our results indicate that the very well known NCA should be used with caution close to the symmetric point of the Anderson model.

En Route towards European Clinical Breakpoints for Veterinary Antimicrobial Susceptibility Testing: A Position Paper Explaining the VetCAST Approach.

PubMed

Toutain, Pierre-Louis; Bousquet-Mélou, Alain; Damborg, Peter; Ferran, Aude A; Mevius, Dik; Pelligand, Ludovic; Veldman, Kees T; Lees, Peter

2017-01-01

VetCAST is the EUCAST sub-committee for Veterinary Antimicrobial Susceptibility Testing. Its remit is to define clinical breakpoints (CBPs) for antimicrobial drugs (AMDs) used in veterinary medicine in Europe. This position paper outlines the procedures and reviews scientific options to solve challenges for the determination of specific CBPs for animal species, drug substances and disease conditions. VetCAST will adopt EUCAST approaches: the initial step will be data assessment; then procedures for decisions on the CBP; and finally the release of recommendations for CBP implementation. The principal challenges anticipated by VetCAST are those associated with the differing modalities of AMD administration, including mass medication, specific long-acting product formulations or local administration. Specific challenges comprise mastitis treatment in dairy cattle, the range of species and within species breed considerations and several other variable factors not relevant to human medicine. Each CBP will be based on consideration of: (i) an epidemiological cut-off value (ECOFF) - the highest MIC that defines the upper end of the wild-type MIC distribution; (ii) a PK/PD breakpoint obtained from pre-clinical pharmacokinetic data [this PK/PD break-point is the highest possible MIC for which a given percentage of animals in the target population achieves a critical value for the selected PK/PD index ( f AUC/MIC or f T > MIC)] and (iii) when possible, a clinical cut-off, that is the relationship between MIC and clinical cure. For the latter, VetCAST acknowledges the paucity of such data in veterinary medicine. When a CBP cannot be established, VetCAST will recommend use of ECOFF as surrogate. For decision steps, VetCAST will follow EUCAST procedures involving transparency, consensus and independence. VetCAST will ensure freely available dissemination of information, concerning standards, guidelines, ECOFF, PK/PD breakpoints, CBPs and other relevant information for AST implementation. Finally, after establishing a CBP, VetCAST will promulgate expert comments and/or recommendations associated with CBPs to facilitate their sound implementation in a clinical setting.

En Route towards European Clinical Breakpoints for Veterinary Antimicrobial Susceptibility Testing: A Position Paper Explaining the VetCAST Approach

PubMed Central

Toutain, Pierre-Louis; Bousquet-Mélou, Alain; Damborg, Peter; Ferran, Aude A.; Mevius, Dik; Pelligand, Ludovic; Veldman, Kees T.; Lees, Peter

2017-01-01

VetCAST is the EUCAST sub-committee for Veterinary Antimicrobial Susceptibility Testing. Its remit is to define clinical breakpoints (CBPs) for antimicrobial drugs (AMDs) used in veterinary medicine in Europe. This position paper outlines the procedures and reviews scientific options to solve challenges for the determination of specific CBPs for animal species, drug substances and disease conditions. VetCAST will adopt EUCAST approaches: the initial step will be data assessment; then procedures for decisions on the CBP; and finally the release of recommendations for CBP implementation. The principal challenges anticipated by VetCAST are those associated with the differing modalities of AMD administration, including mass medication, specific long-acting product formulations or local administration. Specific challenges comprise mastitis treatment in dairy cattle, the range of species and within species breed considerations and several other variable factors not relevant to human medicine. Each CBP will be based on consideration of: (i) an epidemiological cut-off value (ECOFF) – the highest MIC that defines the upper end of the wild-type MIC distribution; (ii) a PK/PD breakpoint obtained from pre-clinical pharmacokinetic data [this PK/PD break-point is the highest possible MIC for which a given percentage of animals in the target population achieves a critical value for the selected PK/PD index (fAUC/MIC or fT > MIC)] and (iii) when possible, a clinical cut-off, that is the relationship between MIC and clinical cure. For the latter, VetCAST acknowledges the paucity of such data in veterinary medicine. When a CBP cannot be established, VetCAST will recommend use of ECOFF as surrogate. For decision steps, VetCAST will follow EUCAST procedures involving transparency, consensus and independence. VetCAST will ensure freely available dissemination of information, concerning standards, guidelines, ECOFF, PK/PD breakpoints, CBPs and other relevant information for AST implementation. Finally, after establishing a CBP, VetCAST will promulgate expert comments and/or recommendations associated with CBPs to facilitate their sound implementation in a clinical setting. PMID:29326661

Application of self-consolidating concrete in bridge structures : final report.

DOT National Transportation Integrated Search

2011-05-01

The objectives of this research were to evaluate the feasibility and performance of self-consolidating concrete (SCC) made with local aggregates for use in cast-in-place and precast concrete applications and to develop draft specifications, acceptanc...

An Empirical Study of Cultures of Assessment in Higher Education

ERIC Educational Resources Information Center

Fuller, Matthew B.

2013-01-01

Higher education campus leaders face a complex state of affairs regarding the documentation of evidence of student learning. There is no shortage of technical guidance for conducting assessment (e.g. Allen, 2006; Bresciani, 2007; Bresciani, Zelna, & Anderson, 2004; Lui, 2011; Maki, 2010; Suskie, 2009; Walvrood & Anderson, 2010), and a…

75 FR 57974 - Senior Executive Service Performance Review Board

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-23

... individuals listed below: Aguilar, David V. Alexander, Barbara Alikhan, Arif Anderson, Audrey Anderson, Gary L. Armstrong, Charles R. Ayala, Janice Aytes, Michael L. Bacon, Roxana Baldwin, William D. Baroukh, Nader Barr... N. Muenchau, Ernest Myers, David L. Neal, Jeffrey R. Neufeld, Donald W. Nicholson, David O'Connell...

Graduate students Chris Hill and Ryan Anderson examine a cross section of the prototype rocket engine igniter.

NASA Image and Video Library

2017-09-08

Majid Babai along with Dr. Judy Schneider, and graduate students Chris Hill and Ryan Anderson examine a cross section of the prototype rocket engine igniter created by an innovative bi-metallic 3-D printing advanced manufacturing process under a microscope.

Fundamental Studies in Blow-Down and Cryogenic Cooling

DTIC Science & Technology

1993-09-01

Mudawar , I. and Anderson, T.M., -High Flux Electronic Cooling by Means of Pool Boiling - Part I: Parametric Investigation of the Effects of Coolant...Electronics, pp. 25-34, 1989. 30 Mudawar , I. and Anderson, T.M., "High Flux Electronic Cooling by Means of Pool Boiling - Part 1I: Optimization of

60. View of radome hydraulic module control center in mezzanine ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

60. View of radome hydraulic module control center in mezzanine level in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

33. View of data converter and power supply for TR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. View of data converter and power supply for TR system in transmitter building no. 102, mezzanine level. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Expedition 14 Crew and Backup Crew Training

NASA Image and Video Library

2006-05-24

JSC2006-E-20053 (24 May 2006) --- Astronaut Clayton C. Anderson, Expedition 14 backup flight engineer, participates in Journals experiment overview training in the Flight Operations Facility at Johnson Space Center. This type of training is a presentation format regarding the experiment objectives and tools. Training instructor Lindsay Kirschner assisted Anderson.

Prevention of HIV/AIDS Education in Rural Communities II.

ERIC Educational Resources Information Center

Torabi, Mohammad R., Ed.

1997-01-01

This second special issue of the Health Education Monograph Series on HIV/AIDS Prevention in Rural Communities presents seven articles: (1) "Preventing Maternal-Infant Transmission of HIV: Social and Ethical Issues" (James G. Anderson, Marilyn M. Anderson, and Tara Booth); (2) "HIV Infection in Diverse Rural Population: Migrant Farm…

77. View of interior of room 115, building no. 102, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

77. View of interior of room 115, building no. 102, with technical publications and equipment for testing. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Evaluation of the train signal and rail systems for the Anton Anderson Memorial Tunnel.

DOT National Transportation Integrated Search

2014-07-01

The Whittier Access Project was completed in 2000. One phase of the project was to convert the 2.5 mile long Anton Anderson : Memorial Tunnel (Whittier Tunnel) into the worlds only dual-use highway/railroad tunnel with one way reversible highway t...

Telecommunications: Systems and Services. [SITE 2002 Section].

ERIC Educational Resources Information Center

Abramson, Gertrude, Ed.

This document contains the following papers on telecommunications systems and services from the SITE (Society for Information Technology & Teacher Education) 2002 conference: (1) "Using the Web To Provide Parent Progress Reports on Standards for All Students: Developing the System" (Kevin M. Anderson and Cindy L. Anderson); (2) "Computer and…

U.S. Geological Survey's ShakeCast: A cloud-based future

USGS Publications Warehouse

Wald, David J.; Lin, Kuo-Wan; Turner, Loren; Bekiri, Nebi

2014-01-01

When an earthquake occurs, the U. S. Geological Survey (USGS) ShakeMap portrays the extent of potentially damaging shaking. In turn, the ShakeCast system, a freely-available, post-earthquake situational awareness application, automatically retrieves earthquake shaking data from ShakeMap, compares intensity measures against users’ facilities, sends notifications of potential damage to responsible parties, and generates facility damage assessment maps and other web-based products for emergency managers and responders. ShakeCast is particularly suitable for earthquake planning and response purposes by Departments of Transportation (DOTs), critical facility and lifeline utilities, large businesses, engineering and financial services, and loss and risk modelers. Recent important developments to the ShakeCast system and its user base are described. The newly-released Version 3 of the ShakeCast system encompasses advancements in seismology, earthquake engineering, and information technology applicable to the legacy ShakeCast installation (Version 2). In particular, this upgrade includes a full statistical fragility analysis framework for general assessment of structures as part of the near real-time system, direct access to additional earthquake-specific USGS products besides ShakeMap (PAGER, DYFI?, tectonic summary, etc.), significant improvements in the graphical user interface, including a console view for operations centers, and custom, user-defined hazard and loss modules. The release also introduces a new adaption option to port ShakeCast to the "cloud". Employing Amazon Web Services (AWS), users now have a low-cost alternative to local hosting, by fully offloading hardware, software, and communication obligations to the cloud. Other advantages of the "ShakeCast Cloud" strategy include (1) Reliability and robustness of offsite operations, (2) Scalability naturally accommodated, (3), Serviceability, problems reduced due to software and hardware uniformity, (4) Testability, freely available for new users, (5) Remotely supported, allowing expert-facilitated maintenance, (6) Adoptability, simplified with disk images, and (7) Security, built in at the very high level associated with AWS. The ShakeCast user base continues to expand and broaden. For example, Caltrans, the prototypical ShakeCast user and development supporter, has been providing guidance to other DOTs on the use of the National Bridge Inventory (NBI) database to implement fully-functional ShakeCast systems in their states. A long-term goal underway is to further "connect the DOTs" via a Transportation Pooled Fund (TPF) with participating state DOTs. We also review some of the many other users and uses of ShakeCast. Lastly, on the hazard input front, we detail related ShakeMap improvements and ongoing advancements in estimating the likelihood of shaking-induced secondary hazards at structures, facilities, bridges, and along roadways due to landslides and liquefaction, and implemented within the ShakeCast framework.

A combined arc-melting and tilt-casting furnace for the manufacture of high-purity bulk metallic glass materials.

PubMed

Soinila, E; Pihlajamäki, T; Bossuyt, S; Hänninen, H

2011-07-01

An arc-melting furnace which includes a tilt-casting facility was designed and built, for the purpose of producing bulk metallic glass specimens. Tilt-casting was chosen because reportedly, in combination with high-purity processing, it produces the best fatigue endurance in Zr-based bulk metallic glasses. Incorporating the alloying and casting facilities in a single piece of equipment reduces the amount of laboratory space and capital investment needed. Eliminating the sample transfer step from the production process also saves time and reduces sample contamination. This is important because the glass forming ability in many alloy systems, such as Zr-based glass-forming alloys, deteriorates rapidly with increasing oxygen content of the specimen. The challenge was to create a versatile instrument, in which high purity conditions can be maintained throughout the process, even when melting alloys with high affinity for oxygen. Therefore, the design provides a high-vacuum chamber to be filled with a low-oxygen inert atmosphere, and takes special care to keep the system hermetically sealed throughout the process. In particular, movements of the arc-melting electrode and sample manipulator arm are accommodated by deformable metal bellows, rather than sliding O-ring seals, and the whole furnace is tilted for tilt-casting. This performance of the furnace is demonstrated by alloying and casting Zr(55)Cu(30)Al(10)Ni(5) directly into rods up to ø 10 mm which are verified to be amorphous by x-ray diffraction and differential scanning calorimetry, and to exhibit locally ductile fracture at liquid nitrogen temperature.

The management of open tibial fractures in children: a retrospective case series of eight years' experience of 61 cases at a paediatric specialist centre.

PubMed

Nandra, R S; Wu, F; Gaffey, A; Bache, C E

2017-04-01

Following the introduction of national standards in 2009, most major paediatric trauma is now triaged to specialist units offering combined orthopaedic and plastic surgical expertise. We investigated the management of open tibia fractures at a paediatric trauma centre, primarily reporting the risk of infection and rate of union. A retrospective review was performed on 61 children who between 2007 and 2015 presented with an open tibia fracture. Their mean age was nine years (2 to 16) and the median follow-up was ten months (interquartile range 5 to 18). Management involved IV antibiotics, early debridement and combined treatment of the skeletal and soft-tissue injuries in line with standards proposed by the British Orthopaedic Association. There were 36 diaphyseal fractures and 25 distal tibial fractures. Of the distal fractures, eight involved the physis. Motor vehicle collisions accounted for two thirds of the injuries and 38 patients (62%) arrived outside of normal working hours. The initial method of stabilisation comprised: casting in nine cases (15%); elastic nailing in 19 (31%); Kirschner (K)-wiring in 13 (21%); intramedullary nailing in one (2%); open reduction and plate fixation in four (7%); and external fixation in 15 (25%). Wound management comprised: primary wound closure in 24 (39%), delayed primary closure in 11 (18%), split skin graft (SSG) in eight (13%), local flap with SSG in 17 (28%) and a free flap in one. A total of 43 fractures (70%) were Gustilo-Anderson grade III. There were four superficial (6.6%) and three (4.9%) deep infections. Two deep infections occurred following open reduction and plate fixation and the third after K-wire fixation of a distal fracture. No patient who underwent primary wound closure developed an infection. All the fractures united, although nine patients required revision of a mono-lateral to circular frame for delayed union (two) or for altered alignment or length (seven). The mean time to union was two weeks longer in diaphyseal fractures than in distal fractures (13 weeks versus 10.8 weeks, p = 0.016). Children aged > 12 years had a significantly longer time to union than those aged < 12 years (16.3 weeks versus 11.4 weeks, p = 0.045). The length of stay in hospital for patients with a Gustilo-Anderson grade IIIB fracture was twice as long as for less severe injuries. Fractures in children heal better than those in adults. Based on our experience of deep infection we discourage the use of internal fixation with a plate for open tibial fractures in children. We advocate aggressive initial wound debridement in theatre with early definitive combined orthopaedic and plastic surgery in order to obtain skeletal stabilisation and soft-tissue cover. Cite this article: Bone Joint J 2017;99-B:544-53. ©2017 The British Editorial Society of Bone & Joint Surgery.

Detection and reconstruction of solidification cracks - Laser ultrasonic measurements during the continuous casting process of aluminum

NASA Astrophysics Data System (ADS)

Mitter, Thomas; Grün, Hubert; Roither, Jürgen; Betz, Andreas; Bozorgi, Salar; Reitinger, Bernhard; Burgholzer, Peter

2014-05-01

In the continuous casting process the avoidance and rapid detection of occurring solidification cracks in the slab is a crucial issue, in particular for the maintenance of a high quality level in further production processes. Due to the elevated temperatures of the slab surface a remote sensing non-destructive tool for quality inspection is required, which is also applicable for the harsh industrial environment. In this work the application of laser ultrasound (LUS) technique during the continuous casting process in industrial environment is shown. The proof of principle of the detection of the centered solidification cracks is shown by pulse-echo measurements with laser ultrasonic equipment for inline quality inspection. Preliminary examinations in the lab of different casted samples have shown the distinguishability of slabs with and without any solidification cracks. Furthermore the damping of the bulk wave has been used for the prediction of the dimension of the crack. With an adapted "synthetic aperture focusing technique" (SAFT) algorithm the image reconstruction of multiple measurements at different positions around the circumference has provided enough information for the estimation of the localization and extension of the centered solidification cracks. Subsequent first measurements using this laser ultrasonic setup during the continuous casting of aluminum were carried out and showed the proof of principle in an industrial environment with elevated temperatures, dust, cooling water and vibrations.

Uncovering the local inelastic interactions during manufacture of ductile cast iron: How the substructure of the graphite particles can induce residual stress concentrations in the matrix

NASA Astrophysics Data System (ADS)

Andriollo, Tito; Hellström, Kristina; Sonne, Mads Rostgaard; Thorborg, Jesper; Tiedje, Niels; Hattel, Jesper

2018-02-01

Recent X-ray diffraction (XRD) measurements have revealed that plastic deformation and a residual elastic strain field can be present around the graphite particles in ductile cast iron after manufacturing, probably due to some local mismatch in thermal contraction. However, as only one component of the elastic strain tensor could be obtained from the XRD data, the shape and magnitude of the associated residual stress field have remained unknown. To compensate for this and to provide theoretical insight into this unexplored topic, a combined experimental-numerical approach is presented in this paper. First, a material equivalent to the ductile cast iron matrix is manufactured and subjected to dilatometric and high-temperature tensile tests. Subsequently, a two-scale hierarchical top-down model is devised, calibrated on the basis of the collected data and used to simulate the interaction between the graphite particles and the matrix during manufacturing of the industrial part considered in the XRD study. The model indicates that, besides the viscoplastic deformation of the matrix, the effect of the inelastic deformation of the graphite has to be considered to explain the magnitude of the XRD strain. Moreover, the model shows that the large elastic strain perturbations recorded with XRD close to the graphite-matrix interface are not artifacts due to e.g. sharp gradients in chemical composition, but correspond to residual stress concentrations induced by the conical sectors forming the internal structure of the graphite particles. In contrast to common belief, these results thus suggest that ductile cast iron parts cannot be considered, in general, as stress-free at the microstructural scale.

Phase boundaries of power-law Anderson and Kondo models: A poor man's scaling study

NASA Astrophysics Data System (ADS)

Cheng, Mengxing; Chowdhury, Tathagata; Mohammed, Aaron; Ingersent, Kevin

2017-07-01

We use the poor man's scaling approach to study the phase boundaries of a pair of quantum impurity models featuring a power-law density of states ρ (ɛ ) ∝|ɛ| r , either vanishing (for r >0 ) or diverging (for r <0 ) at the Fermi energy ɛ =0 , that gives rise to quantum phase transitions between local-moment and Kondo-screened phases. For the Anderson model with a pseudogap (i.e., r >0 ), we find the phase boundary for (a) 0 1 , where the phases are separated by first-order quantum phase transitions that are accessible only for broken p-h symmetry. For the p-h-symmetric Kondo model with easy-axis or easy-plane anisotropy of the impurity-band spin exchange, the phase boundary and scaling trajectories are obtained for both r >0 and r <0 . Throughout the regime of weak-to-moderate impurity-band coupling in which poor man's scaling is expected to be valid, the approach predicts phase boundaries in excellent qualitative and good quantitative agreement with the nonperturbative numerical renormalization group, while also establishing the functional relations between model parameters along these boundaries.

Fermi edge singularity in a tunnel junction

NASA Astrophysics Data System (ADS)

Zhang, Jin; Sherkunov, Yury; D'Ambrumenil, Nicholas; Muzykantskii, Boris

2010-03-01

We present results on the non-equilibrium Fermi edge singularity (FES) problem in tunnel junctions. The FES, which is present in a Fermi gas subject to any sudden change of potential, manifests itself in the final state many body interaction between the electrons in the leads [1]. We establish a connection between the FES problem in a tunnel junction and the Full Counting Statistics (FCS) for the device [2]. We find that the exact profile of the changing potential (or the profile for the barrier opening and closing in the tunnel junction case) strongly affects the overlap between the initial and final state of the Fermi gas. We factorize the contribution to the FES into two approximately independent terms: one is connected with the short time opening process while the other is concerned with the long time asymptotic effect, namely the Anderson orthogonality catastrophe. We consider applications to a localized level coupled through a tunnel barrier to a 1D lead driven out of equilibrium [3]. References: [1] G. Mahan, Phys. Rev. 163, 1612 (1967); P. Nozieres and C. T. De Dominicis, Phys. Rev. 178, 1079 (1969); P. Anderson, Phys. Rev. Lett. 18, 1049 (1967) [2] J. Zhang, Y. Sherkunov, N. d'Ambrumenil, and B. Muzykantskii, ArXiv:0909.3427 [3] D. Abanin and L. Levitov, Phys. Rev. Lett. 94, 186803 (2005)

Anderson metal-insulator transitions with classical magnetic impurities

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

Jung, Daniel; Kettemann, Stefan

We study the effects of classical magnetic impurities on the Anderson metal-insulator transition (AMIT) numerically. In particular we find that while a finite concentration of Ising impurities lowers the critical value of the site-diagonal disorder amplitude W{sub c}, in the presence of Heisenberg impurities, W{sub c} is first increased with increasing exchange coupling strength J due to time-reversal symmetry breaking. The resulting scaling with J is compared to analytical predictions by Wegner [1]. The results are obtained numerically, based on a finite-size scaling procedure for the typical density of states [2], which is the geometric average of the local densitymore » of states. The latter can efficiently be calculated using the kernel polynomial method [3]. Although still suffering from methodical shortcomings, our method proves to deliver results close to established results for the orthogonal symmetry class [4]. We extend previous approaches [5] by combining the KPM with a finite-size scaling analysis. We also discuss the relevance of our findings for systems like phosphor-doped silicon (Si:P), which are known to exhibit a quantum phase transition from metal to insulator driven by the interplay of both interaction and disorder, accompanied by the presence of a finite concentration of magnetic moments [6].« less

Disorder-Induced Topological State Transition in Photonic Metamaterials

NASA Astrophysics Data System (ADS)

Liu, Changxu; Gao, Wenlong; Yang, Biao; Zhang, Shuang

2017-11-01

The topological state transition has been widely studied based on the quantized topological band invariant such as the Chern number for the system without intense randomness that may break the band structures. We numerically demonstrate the disorder-induced state transition in the photonic topological systems for the first time. Instead of applying the ill-defined topological band invariant in a disordered system, we utilize an empirical parameter to unambiguously illustrate the state transition of the topological metamaterials. Before the state transition, we observe a robust surface state with well-confined electromagnetic waves propagating unidirectionally, immune to the disorder from permittivity fluctuation up to 60% of the original value. During the transition, a hybrid state composed of a quasiunidirectional surface mode and intensively localized hot spots is established, a result of the competition between the topological protection and Anderson localization.

Bell pair creation in current of Kondo-correlated dot

NASA Astrophysics Data System (ADS)

Sakano, Rui; Oguri, Akira; Nishikawa, Yunori; Abe, Eisuke

Recently, local-Fermi-liquid properties in non-linear currents and shot noises through the Kondo dot have been investigated both theoretically and experimentally. We suggest a new entangled-electron-pair generator utilizing mechanism of quasiparticle-pair creation which has been observed as enhancement of shot noise in the quantum dot. Using the renormalized perturbation theory for an orbital-degenerate impurity Anderson model and the full counting statistics, we calculate the Clauser-Horne-Shimony-Holt type Bell's correlator for currents through correlated two different channels of a Kondo correlated dot. It is shown that residual exchange-interactions of the local-Fermi-liquid create spin-entangled quasiparticle-pairs in nonlinear current and this results in violation of the Bell's inequality. This work was partially supported by JSPS KAKENHI Grant Numbers JP26220711, JP26400319, JP15K05181 and JP16K17723.

Broken symmetries, zero-energy modes, and quantum transport in disordered graphene: from supermetallic to insulating regimes.

PubMed

Cresti, Alessandro; Ortmann, Frank; Louvet, Thibaud; Van Tuan, Dinh; Roche, Stephan

2013-05-10

The role of defect-induced zero-energy modes on charge transport in graphene is investigated using Kubo and Landauer transport calculations. By tuning the density of random distributions of monovacancies either equally populating the two sublattices or exclusively located on a single sublattice, all conduction regimes are covered from direct tunneling through evanescent modes to mesoscopic transport in bulk disordered graphene. Depending on the transport measurement geometry, defect density, and broken sublattice symmetry, the Dirac-point conductivity is either exceptionally robust against disorder (supermetallic state) or suppressed through a gap opening or by algebraic localization of zero-energy modes, whereas weak localization and the Anderson insulating regime are obtained for higher energies. These findings clarify the contribution of zero-energy modes to transport at the Dirac point, hitherto controversial.

Universality in quantum chaos and the one-parameter scaling theory.

PubMed

García-García, Antonio M; Wang, Jiao

2008-02-22

The one-parameter scaling theory is adapted to the context of quantum chaos. We define a generalized dimensionless conductance, g, semiclassically and then study Anderson localization corrections by renormalization group techniques. This analysis permits a characterization of the universality classes associated to a metal (g-->infinity), an insulator (g-->0), and the metal-insulator transition (g-->g(c)) in quantum chaos provided that the classical phase space is not mixed. According to our results the universality class related to the metallic limit includes all the systems in which the Bohigas-Giannoni-Schmit conjecture holds but automatically excludes those in which dynamical localization effects are important. The universality class related to the metal-insulator transition is characterized by classical superdiffusion or a fractal spectrum in low dimensions (d < or = 2). Several examples are discussed in detail.

Scaling in Plateau-to-Plateau Transition: A Direct Connection of Quantum Hall Systems with the Anderson Localization Model

NASA Astrophysics Data System (ADS)

Li, Wanli; Vicente, C. L.; Xia, J. S.; Pan, W.; Tsui, D. C.; Pfeiffer, L. N.; West, K. W.

2009-05-01

The quantum Hall-plateau transition was studied at temperatures down to 1 mK in a random alloy disordered high mobility two-dimensional electron gas. A perfect power-law scaling with κ=0.42 was observed from 1.2 K down to 12 mK. This perfect scaling terminates sharply at a saturation temperature of Ts˜10mK. The saturation is identified as a finite-size effect when the quantum phase coherence length (Lϕ∝T-p/2) reaches the sample size (W) of millimeter scale. From a size dependent study, Ts∝W-1 was observed and p=2 was obtained. The exponent of the localization length, determined directly from the measured κ and p, is ν=2.38, and the dynamic critical exponent z=1.

View of Anderson removing the EAS during a session of EVA on Expedition 15

NASA Image and Video Library

2007-07-23

ISS015-E-19140 (23 July 2007) --- Anchored to the Canadarm2 foot restraint, astronaut Clay Anderson, Expedition 15 flight engineer, removes the Early Ammonia Servicer (EAS) from its place on the International Space Station during a session of extravehicular activity (EVA). Anderson later jettisoned the EAS by shoving it opposite of the station's direction of travel. The EAS was installed on the P6 truss during STS-105 in August 2001, as an ammonia reservoir if a leak had occurred. It was never used, and was no longer needed after the permanent cooling system was activated last December. The blackness of space and Earth's horizon provide the backdrop for the scene.

View of Anderson removing the EAS during a session of EVA on Expedition 15

NASA Image and Video Library

2007-07-23

ISS015-E-19135 (23 July 2007) --- Anchored to the Canadarm2 foot restraint, astronaut Clay Anderson, Expedition 15 flight engineer, removes the Early Ammonia Servicer (EAS) from its place on the International Space Station during a session of extravehicular activity (EVA). Anderson later jettisoned the EAS by shoving it opposite of the station's direction of travel. The EAS was installed on the P6 truss during STS-105 in August 2001, as an ammonia reservoir if a leak had occurred. It was never used, and was no longer needed after the permanent cooling system was activated last December. The blackness of space and Earth's horizon provide the backdrop for the scene.

Financial protection against nuclear hazards: thirty years' experience under the Price-Anderson Act

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

Rockett, L.R.; Hayn, I.

1984-01-01

The purpose of this study is to evaluate the operation of the Price-Anderson Act in the light of the last 10 years' experience and the changes that have occurred during that period both in the law and regulations and in the nuclear and insurance industries, and to provide an independent analysis of various proposals to extend or amend the Act prior to its 1987 expiration. The report does not analyze the impact of the Silkwood v. Kerr McGee Corp. decision. The five chapters cover historical background, financial protection under the Price-Anderson Act and in the absence of the Act, fundamentalmore » policy issues, and alternative proposals.« less

Observation of the Anderson metal-insulator transition with atomic matter waves: Theory and experiment

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

Lemarie, Gabriel; Delande, Dominique; Chabe, Julien

Using a cold atomic gas exposed to laser pulses - a realization of the chaotic quasiperiodic kicked rotor with three incommensurate frequencies - we study experimentally and theoretically the Anderson metal-insulator transition in three dimensions. Sensitive measurements of the atomic wave function and the use of finite-size scaling techniques make it possible to unambiguously demonstrate the existence of a quantum phase transition and to measure its critical exponents. By taking proper account of systematic corrections to one-parameter scaling, we show the universality of the critical exponent {nu}=1.59{+-}0.01, which is found to be equal to the one previously computed for themore » Anderson model.« less

"Bringing Taxonomy to the Service of Genetics": Edgar Anderson and Introgressive Hybridization.

PubMed

Kleinman, Kim

2016-12-01

In introgressive hybridization (the repeated backcrossing of hybrids with parental populations), Edgar Anderson found a source for variation upon which natural selection could work. In his 1953 review article "Introgressive Hybridization," he asserted that he was "bringing taxonomy to the service of genetics" whereas distinguished colleagues such as Theodosius Dobzhansky and Ernst Mayr did the precise opposite. His work as a geneticist particularly focused on linkage and recombination and was enriched by collaborations with Missouri Botanical Garden colleagues interested in taxonomy as well as with cytologists C.D. Darlington and Karl Sax. As the culmination of a biosystemtatic research program, Anderson's views challenged the mainstream of the Evolutionary Synthesis.

Microscopic Approach to Magnetism and Superconductivity of f-Electron Systems with Filled Skutterudite Structure

NASA Astrophysics Data System (ADS)

Hotta, Takashi

2005-04-01

In order to gain a deep insight into f-electron properties of filled skutterudite compounds from a microscopic viewpoint, we investigate the multiorbital Anderson model including Coulomb interactions, spin-orbit coupling, and crystalline electric field effect. First we examine the local f-electron state in detail in comparison with the results of LS and j-j coupling schemes. For each case of n=1--13, where n is the number of f electrons per rare-earth ion, the model is analyzed by using the numerical renormalization group (NRG) method to evaluate magnetic susceptibility and entropy of f electron. In particular, for the f 2-electron system corresponding to the Pr-based filled skutterudite, it is found that magnetic fluctuations significantly remain at low temperatures, even when the ground state is Γ1 singlet, if Γ_4(2) triplet is the excited state with small excitation energy. In order to make further step to construct a simplified model which can be treated even in a periodic system, we also analyze the Anderson model constructed based on the j-j coupling scheme by using the NRG method. It is clearly observed that the magnetic properties are quite similar to those of the original Anderson model. Then, we construct an orbital degenerate Hubbard model based on the j-j coupling scheme to investigate the mechanism of superconductivity of filled skutterudites. In the 2-site model, we carefully evaluate the superconducting pair susceptibility for the case of n=2 and find that the susceptibility for off-site Cooper pair is clearly enhanced only in a transition region in which the singlet and triplet ground states are interchanged. We envision a scenario that unconventional superconductivity induced by magnetic fluctuations may occur in the f 2-electron system with Γ1 ground state such as Pr-based filled skutterudite compounds.

Development of automated system based on neural network algorithm for detecting defects on molds installed on casting machines

NASA Astrophysics Data System (ADS)

Bazhin, V. Yu; Danilov, I. V.; Petrov, P. A.

2018-05-01

During the casting of light alloys and ligatures based on aluminum and magnesium, problems of the qualitative distribution of the metal and its crystallization in the mold arise. To monitor the defects of molds on the casting conveyor, a camera with a resolution of 780 x 580 pixels and a shooting rate of 75 frames per second was selected. Images of molds from casting machines were used as input data for neural network algorithm. On the preparation of a digital database and its analytical evaluation stage, the architecture of the convolutional neural network was chosen for the algorithm. The information flow from the local controller is transferred to the OPC server and then to the SCADA system of foundry. After the training, accuracy of neural network defect recognition was about 95.1% on a validation split. After the training, weight coefficients of the neural network were used on testing split and algorithm had identical accuracy with validation images. The proposed technical solutions make it possible to increase the efficiency of the automated process control system in the foundry by expanding the digital database.

Influence of friction stir processing on the room temperature fatigue cracking mechanisms of A356 aluminum alloy

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

Nelaturu, Phalgun; Jana, Saumyadeep; Mishra, Rajiv S.

Here, failure by fatigue is a common problem associated with cast aluminum alloys due to defects like shrinkage porosities, non-metallic inclusions, etc. Friction stir processing (FSP) has recently emerged as an effective technique for local modification of microstructure. This study investigates the fatigue crack initiation and growth mechanisms in cast and FSPed A356 aluminum alloy. Two sets of parameters were used to friction stir the cast alloy resulting in the complete modification the cast microstructure to a wrought microstructure. Both the FSPed microstructures exhibited severe abnormal grain growth (AGG) after heat treatment leading to a multimodal grain size distribution –more » the grain sizes ranging from a few microns to a few millimeters. One of the FSP conditions displayed an excellent improvement in fatigue life by an order of magnitude, while the other condition displayed an unexpectedly large scatter in fatigue lives. Detailed study of the fractured fatigue specimens by electron back scattered diffraction (EBSD) revealed that both, fatigue crack initiation and propagation, were intimately tied to the grain size as well as the grain misorientations in the microstructure.« less

Influence of friction stir processing on the room temperature fatigue cracking mechanisms of A356 aluminum alloy

DOE PAGES

Nelaturu, Phalgun; Jana, Saumyadeep; Mishra, Rajiv S.; ...

2018-01-11

Here, failure by fatigue is a common problem associated with cast aluminum alloys due to defects like shrinkage porosities, non-metallic inclusions, etc. Friction stir processing (FSP) has recently emerged as an effective technique for local modification of microstructure. This study investigates the fatigue crack initiation and growth mechanisms in cast and FSPed A356 aluminum alloy. Two sets of parameters were used to friction stir the cast alloy resulting in the complete modification the cast microstructure to a wrought microstructure. Both the FSPed microstructures exhibited severe abnormal grain growth (AGG) after heat treatment leading to a multimodal grain size distribution –more » the grain sizes ranging from a few microns to a few millimeters. One of the FSP conditions displayed an excellent improvement in fatigue life by an order of magnitude, while the other condition displayed an unexpectedly large scatter in fatigue lives. Detailed study of the fractured fatigue specimens by electron back scattered diffraction (EBSD) revealed that both, fatigue crack initiation and propagation, were intimately tied to the grain size as well as the grain misorientations in the microstructure.« less

Summary of Research Report

NASA Technical Reports Server (NTRS)

Elishakoff, Isaac

1998-01-01

Ten papers, published in various publications, on buckling, and the effects of imperfections on various structures are presented. These papers are: (1) Buckling mode localization in elastic plates due to misplacement in the stiffner location; (2) On vibrational imperfection sensitivity on Augusti's model structure in the vicinity of a non-linear static state; (3) Imperfection sensitivity due to elastic moduli in the Roorda Koiter frame; (4) Buckling mode localization in a multi-span periodic structure with a disorder in a single span; (5) Prediction of natural frequency and buckling load variability due to uncertainty in material properties by convex modeling; (6) Derivation of multi-dimensional ellipsoidal convex model for experimental data; (7) Passive control of buckling deformation via Anderson localization phenomenon; (8)Effect of the thickness and initial im perfection on buckling on composite cylindrical shells: asymptotic analysis and numerical results by BOSOR4 and PANDA2; (9) Worst case estimation of homology design by convex analysis; (10) Buckling of structures with uncertain imperfections - Personal perspective.

Direct measurement of superdiffusive energy transport in disordered granular chains.

PubMed

Kim, Eunho; Martínez, Alejandro J; Phenisee, Sean E; Kevrekidis, P G; Porter, Mason A; Yang, Jinkyu

2018-02-13

Energy transport properties in heterogeneous materials have attracted scientific interest for more than half of a century, and they continue to offer fundamental and rich questions. One of the outstanding challenges is to extend Anderson theory for uncorrelated and fully disordered lattices in condensed-matter systems to physical settings in which additional effects compete with disorder. Here we present the first systematic experimental study of energy transport and localization properties in simultaneously disordered and nonlinear granular crystals. In line with prior theoretical studies, we observe in our experiments that disorder and nonlinearity-which individually favor energy localization-can effectively cancel each other out, resulting in the destruction of wave localization. We also show that the combined effect of disorder and nonlinearity can enable manipulation of energy transport speed in granular crystals. Specifically, we experimentally demonstrate superdiffusive transport. Furthermore, our numerical computations suggest that subdiffusive transport should be attainable by controlling the strength of the system's external precompression force.

Do the surface Fermi arcs in Weyl semimetals survive disorder?

NASA Astrophysics Data System (ADS)

Wilson, Justin H.; Pixley, J. H.; Huse, David A.; Refael, Gil; Das Sarma, S.

2018-06-01

We theoretically study the topological robustness of the surface physics induced by Weyl Fermi-arc surface states in the presence of short-ranged quenched disorder and surface-bulk hybridization. This is investigated with numerically exact calculations on a lattice model exhibiting Weyl Fermi arcs. We find that the Fermi-arc surface states, in addition to having a finite lifetime from disorder broadening, hybridize with nonperturbative bulk rare states making them no longer bound to the surface (i.e., they lose their purely surface spectral character). Thus, we provide strong numerical evidence that the Weyl Fermi arcs are not topologically protected from disorder. Nonetheless, the surface chiral velocity is robust and survives in the presence of strong disorder, persisting all the way to the Anderson-localized phase by forming localized current loops that live within the localization length of the surface. Thus, the Weyl semimetal is not topologically robust to the presence of disorder, but the surface chiral velocity is.

Microscopic theoretical study of frequency dependent dielectric constant of heavy fermion systems

NASA Astrophysics Data System (ADS)

Shadangi, Keshab Chandra; Rout, G. C.

2017-05-01

The dielectric polarization and the dielectric constant plays a vital role in the deciding the properties of the Heavy Fermion Systems. In the present communication we consider the periodic Anderson's Model which consists of conduction electron kinetic energy, localized f-electron kinetic energy and the hybridization between the conduction and localized electrons, besides the Coulomb correlation energy. We calculate dielectric polarization which involves two particle Green's functions which are calculated by using Zubarev's Green's function technique. Using the equations of motion of the fermion electron operators. Finally, the temperature and frequency dependent dielectric constant is calculated from the dielectric polarization function. The charge susceptibility and dielectric constant are computed numerically for different physical parameters like the position (Ef) of the f-electron level with respect to fermi level, the strength of the hybridization (V) between the conduction and localized f-electrons, Coulomb correlation potential temperature and optical phonon wave vector (q). The results will be discussed in a reference to the experimental observations of the dielectric constants.

Variable-Range Hopping through Marginally Localized Phonons

NASA Astrophysics Data System (ADS)

Banerjee, Sumilan; Altman, Ehud

2016-03-01

We investigate the effect of coupling Anderson localized particles in one dimension to a system of marginally localized phonons having a symmetry protected delocalized mode at zero frequency. This situation is naturally realized for electrons coupled to phonons in a disordered nanowire as well as for ultracold fermions coupled to phonons of a superfluid in a one-dimensional disordered trap. To determine if the coupled system can be many-body localized we analyze the phonon-mediated hopping transport for both the weak and strong coupling regimes. We show that the usual variable-range hopping mechanism involving a low-order phonon process is ineffective at low temperature due to discreteness of the bath at the required energy. Instead, the system thermalizes through a many-body process involving exchange of a diverging number n ∝-log T of phonons in the low temperature limit. This effect leads to a highly singular prefactor to Mott's well-known formula and strongly suppresses the variable range hopping rate. Finally, we comment on possible implications of this physics in higher dimensional electron-phonon coupled systems.

75 FR 8346 - Proposed CERCLA Administrative Settlement; Anderson-Calhoun Mine and Mill Site, Leadpoint, WA

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

...-Calhoun Mine and Mill Site, Leadpoint, WA AGENCY: Environmental Protection Agency (EPA). ACTION: Notice...-Calhoun Mine and Mill Site in Leadpoint, Washington, with settling party Blue Tee Corporation. The... Anderson-Calhoun Mine and Mill Site in Leadpoint, Washington, EPA Docket No. CERCLA-10-2010-0105 and should...

78 FR 41835 - Inflation Adjustments to the Price-Anderson Act Financial Protection Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

...;Prices of new books are listed in the first FEDERAL REGISTER issue of each #0;week. #0; #0; #0; #0;#0... Price-Anderson Act Financial Protection Regulations AGENCY: Nuclear Regulatory Commission. ACTION: Final rule. SUMMARY: The Atomic Energy Act of 1954, as amended (AEA), requires the U.S. Nuclear Regulatory...

Association of Small Computer Users in Education (ASCUE) Summer Conference. Proceedings (28th, North Myrtle Beach, South Carolina, June 18-22, 1995).

ERIC Educational Resources Information Center

Armel, Donald, Ed.

Papers from a conference on microcomputers are: "Organizational Leadership through Information Technology" (John A. Anderson); "Multimedia in the Classroom--Rejuvenating the Literacy Course" (Stephen T. Anderson, Sr.); "Something New about Notetaking: A Computer-Based Instructional Experiment" (Donald Armel);…

Protecting Our Underwater Friends

ERIC Educational Resources Information Center

Norman, Connie

2012-01-01

The author was fortunate enough to teach in the children's program at Anderson Ranch Arts Center in Snowmass, Colorado. Anderson Ranch is a magical place where artists young and old come to expand their creative spirits. The children's art program spans a wide range of media for children aged six through seventeen. There are classes to explore…

Anderson uses laptop computer in the U.S. Laboratory during Joint Operations

NASA Image and Video Library

2007-06-13

S117-E-07134 (12 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, uses a computer near the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station while Space Shuttle Atlantis (STS-117) was docked with the station. Astronaut Sunita Williams, flight engineer, is at right.

The Effect on Student Achievement of Increasing Kinetic Structure of Teachers' Lectures.

ERIC Educational Resources Information Center

Lamb, William G.; And Others

1979-01-01

Tests O. R. Anderson's theory of kinetic structure of verbal communications by administering lectures on swine flu to high school biology students and then reteaching the lectures with increased commonality. Results weakly support Anderson's theory. Implications are made for training teachers to increase the commonality of their lectures. (CS)

49. View of waveguide system entering building no. 105 (typical ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

49. View of waveguide system entering building no. 105 (typical of all radar scanner buildings), showing testing connection points and monitoring equipment. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

24. View of lobby area on first floor transmitter building ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. View of lobby area on first floor transmitter building no. 102 looking into controlled access corridor and door system - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

61. View of TR spiral access stair system from transmitter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

61. View of TR spiral access stair system from transmitter building no. 102 mezzanine level; note elevator door on right. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

17. View looking north to transmitter building no. 102 from ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. View looking north to transmitter building no. 102 from south along west side of passageway link with TR radome in background. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

42. View of CSMR room equipment status board and operators ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. View of CSMR room equipment status board and operators console with two phone links to MWOC in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

36. View of preset counter (PC) console and tracking console ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. View of preset counter (PC) console and tracking console on right, located in MWOC facility in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

53. View from ground level in building no. 105 showing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

53. View from ground level in building no. 105 showing lower radar scanner switch with incoming waveguide and control switch. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

58. View of high pressure IngersollRand dehumidifier/dessicator and compressor system ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

58. View of high pressure Ingersoll-Rand dehumidifier/dessicator and compressor system to supply dry pressurized air to waveguides. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

23. View of junction of passageway link with radar transmitter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. View of junction of passageway link with radar transmitter building 102 (view looking south) showing main personnel entrance door. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

22. View of vehicle entrance to passageway link system taken ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. View of vehicle entrance to passageway link system taken from looking west. Note DR 3 antenna in background left. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

37. View of detection radar environmental display (DRED) console for ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

37. View of detection radar environmental display (DRED) console for middle DR 2 (structure no. 736) antenna, located in MWOC facility. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

79. View of interior of room 114, supervisor's office, transmitter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

79. View of interior of room 114, supervisor's office, transmitter building no. 102, with microfiche viewer and technical publications. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Theoretical Study of the Saturated Stage of a Relativistic Magnetron

DTIC Science & Technology

2008-11-30

mentioned that an earlier method to estimate the validity of a variational approximation had been given in Ref. [28], where Dexais, Anderson and Lasik ...Zemlyanaya. Phys. Rev. Lett. 80 (1998)5117. [28] M. Dexais. D. Anderson. M. Lasik . Phys. Rev. A 40 (1989) 2441. This research was supported in part by

Improving Earthquake and Explosion Discrimination by Using Love and Rayleigh Wave Magnitudes (Postprint) Annual Report 3

DTIC Science & Technology

2012-03-22

ELEMENT NUMBER 62601F 6. AUTHOR(S) Jessie Bonner1, Anastasia Stroujkova1, and Dale N. Anderson2 5d. PROJECT NUMBER 1010 5e...MAGNITUDES Jessie Bonner1, Anastasia Stroujkova1, and Dale N. Anderson2 Weston Geophysical Corporation1 and Los Alamos National Laboratory2

Student Predisposition to Instructor Feedback and Perceptions of Teaching Presence Predict Motivation toward Online Courses

ERIC Educational Resources Information Center

Cole, Andrew William; Nicolini, Kristine M.; Anderson, Christopher; Bunton, Thomas; Cherney, Maura R.; Fisher, Valerie Cronin; Draeger, Richard, Jr.; Featherston, Michelle; Motel, Laura; Peck, Brittnie; Allen, Mike

2017-01-01

Much research into college student motivation focuses on traditional face-to-face (FtF) classroom settings. Building from previous research in Feedback Intervention Theory (Kluger & DeNisi, 1996) and the Community of Inquiry framework (Anderson, Rourke, Garrison, & Archer, 2001; Garrison, Anderson, & Archer, 1999), this study sought to…

76 FR 56004 - Mannheim Armitage Railway, LLC-Acquisition and Operation Exemption-Certain Trackage Rights of J...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-09

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35540] Mannheim Armitage Railway, LLC--Acquisition and Operation Exemption--Certain Trackage Rights of J. Emil Anderson & Son, Inc... verified notice of exemption \\1\\ under 49 CFR 1150.31 to acquire from J. Emil Anderson & Son, Inc...

Researching the Community of Inquiry Framework: Review, Issues, and Future Directions

ERIC Educational Resources Information Center

Garrison, D. Randy; Arbaugh, J. B.

2007-01-01

Since its publication in "The Internet and Higher Education," Garrison, Anderson, and Archer's [Garrison, D. R., Anderson, T., & Archer, W. (2000). Critical inquiry in a text-based environment: Computer conferencing in higher education. "The Internet and Higher Education," 2(2-3), 87-105.] community of inquiry (CoI) framework has generated…

Adolescent Identities and Sexual Behavior: An Examination of Anderson's Player Hypothesis

ERIC Educational Resources Information Center

Giordano, Peggy C.; Longmore, Monica A.; Manning, Wendy D.; Northcutt, Miriam J.

2009-01-01

We investigate the social and behavioral characteristics of male adolescents who self-identify as players, focusing particularly on Anderson's claim that this social role is inextricably linked with poverty and minority status. Results indicate that black respondents, those affiliated with liberal peers and young men who initially report a…

83. View of specialized maintenance shop in transmitter building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

83. View of specialized maintenance shop in transmitter building no. 101, with shelves of obsolete electronic equipment with disposition and shipping tags. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

30. View of mezzanine floor level in transmitter building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. View of mezzanine floor level in transmitter building no. 102 showing control transmitter electronic cabinets and control modules. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

29. View of typical radio frequency monitor group electronic tubetype ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. View of typical radio frequency monitor group electronic tube-type cabinet. System is water-cooled with antenna assist. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

A Tale of Two Movements: The Power and Consequences of Misremembering "Brown"

ERIC Educational Resources Information Center

Williamson, Joy Ann

2006-01-01

If, as James Anderson stated, a nation committed to democracy and equality has every reason to be ashamed on "Brown v. Board of Education's" 50th anniversary, why the commemoration and celebration? By revising Anderson's challenge to examine the complex role of "Brown" in the nation's memory and history, this chapter…

6. View of DR 3 antenna typical backstay concrete stanchion ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. View of DR 3 antenna typical back-stay concrete stanchion showing embedded anchors and structural steel leg with pin attachment. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

77 FR 72906 - Chessie Logistics Co., LLC-Acquisition and Operation Exemption-J. Emil Anderson & Son, Inc.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-06

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35700] Chessie Logistics Co., LLC--Acquisition and Operation Exemption-- J. Emil Anderson & Son, Inc. Chessie Logistics Co..., including 431 feet of siding, in the city of Melrose Park, Cook County, Ill. (the Track). According to...

Understanding the Advising Learning Process Using Learning Taxonomies

ERIC Educational Resources Information Center

Muehleck, Jeanette K.; Smith, Cathleen L.; Allen, Janine M.

2014-01-01

To better understand the learning that transpires in advising, we used Anderson et al.'s (2001) revision of Bloom's (1956) taxonomy and Krathwohl, Bloom, and Masia's (1964) affective taxonomy to analyze eight student-reported advising outcomes from Smith and Allen (2014). Using the cognitive processes and knowledge domains of Anderson et al.'s…

82. View of specialized maintenance shop in transmitter building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

82. View of specialized maintenance shop in transmitter building no. 101, showing technical publications library and equipment logging trays. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

[Heart involvement in Anderson-Fabry disease: Italian recommendations for diagnostic, follow-up and therapeutic management].

PubMed

Pieruzzi, Federico; Pieroni, Maurizio; Zachara, Elisabetta; Marziliano, Nicola; Morrone, Amelia; Cecchi, Franco

2015-11-01

Anderson-Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations of the GLA gene that encodes alpha-galactosidase A. It is characterized by a multisystemic involvement: the renal, neurological, heart, cochleovestibular and cutaneous systems are the most damaged. Morbidity and mortality of Anderson-Fabry disease depend on renal insufficiency, heart failure and nervous system involvement. Left ventricular hypertrophy is the most common cardiac manifestation followed by conduction system disease, valve dysfunction, and arrhythmias. Mild to moderate left ventricular hypertrophy may simulate a non-obstructive hypertrophic cardiomyopathy. Management of Anderson-Fabry disease starting from the diagnosis of cardiac involvement, the prevention of complications, the therapeutic aspects, up to appropriate clinical follow-up, requires a multidisciplinary approach. According to recent management guidelines, only few evidence-based data are available to guide the clinical and therapeutic approach to this rare disease. An Italian Board, composed by nephrologists, cardiologists, geneticists, pediatricians and neurologists has been established in order to approve by consensus a diagnostic and therapeutic management protocol. The authors report the results of this cardiologic management consensus.

Feature inference with uncertain categorization: Re-assessing Anderson's rational model.

PubMed

Konovalova, Elizaveta; Le Mens, Gaël

2017-09-18

A key function of categories is to help predictions about unobserved features of objects. At the same time, humans are often in situations where the categories of the objects they perceive are uncertain. In an influential paper, Anderson (Psychological Review, 98(3), 409-429, 1991) proposed a rational model for feature inferences with uncertain categorization. A crucial feature of this model is the conditional independence assumption-it assumes that the within category feature correlation is zero. In prior research, this model has been found to provide a poor fit to participants' inferences. This evidence is restricted to task environments inconsistent with the conditional independence assumption. Currently available evidence thus provides little information about how this model would fit participants' inferences in a setting with conditional independence. In four experiments based on a novel paradigm and one experiment based on an existing paradigm, we assess the performance of Anderson's model under conditional independence. We find that this model predicts participants' inferences better than competing models. One model assumes that inferences are based on just the most likely category. The second model is insensitive to categories but sensitive to overall feature correlation. The performance of Anderson's model is evidence that inferences were influenced not only by the more likely category but also by the other candidate category. Our findings suggest that a version of Anderson's model which relaxes the conditional independence assumption will likely perform well in environments characterized by within-category feature correlation.

Fabry disease presenting as apical left ventricular hypertrophy in a patient carrying the missense mutation R118C.

PubMed

Caetano, Francisca; Botelho, Ana; Mota, Paula; Silva, Joana; Leitão Marques, António

2014-03-01

Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by abnormalities of the GLA gene, which encodes the enzyme α-galactosidase A. A deficiency of this enzyme leads to the lysosomal accumulation of glycosphingolipids, which may cause left ventricular hypertrophy that is typically concentric and symmetric. We present the case of a 60-year-old woman with symptoms of dyspnea, atypical chest pain and palpitations, in whom a transthoracic echocardiogram revealed an apical variant of hypertrophic cardiomyopathy. Analysis of specific sarcomeric genetic mutations was negative. The patient underwent a screening protocol for Anderson-Fabry disease, using a dried blood spot test, which was standard at our institution for patients with left ventricular hypertrophy. The enzymatic activity assay revealed reduced α-galactosidase A enzymatic activity. Molecular analysis identified a missense point mutation in the GLA gene (p.R118C). This case report shows that Anderson-Fabry disease may cause an apical form of left ventricular hypertrophy. The diagnosis was only achieved because of systematic screening, which highlights the importance of screening for Anderson-Fabry disease in patients with unexplained left ventricular hypertrophy, including those presenting with more unusual patterns, such as apical variants of left ventricular hypertrophy. This case also supports the idea that the missense mutation R118C is indeed a true pathogenic mutation of Anderson-Fabry disease. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Preliminary report on methodology for calculating coal resources of the Wyodak-Anderson coal zone, Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Ellis, Margaret S.; Gunther, Gregory L.; Flores, Romeo M.; Stricker, Gary D.; Ochs, Allan M.; Schuenemeyer, John H.

1998-01-01

The National Coal Resource Assessment of the Wyodak-Anderson coal zone includes reports on the geology, stratigraphy, quality, and quantity of coal. The calculation of resources is only one aspect of the assessment. Without thorough documentation of the coal resource study and the methods used, the results of our study could be misinterpreted. The task of calculating coal resources included many steps, the use of several commercial software programs, and the incorporation of custom programs. The methods used for calculating coal resources for the Wyodak-Anderson coal zone vary slightly from the methods used in other study areas, and by other workers in the National Coal Resource Assessment. The Wyodak-Anderson coal zone includes up to 10 coal beds in any given location. The net coal thickness of the zone at each data point location was calculated by summing the thickness of all of the coal beds that were greater than 2.5 ft thick. The amount of interburden is not addressed or reported in this coal resource assessment. The amount of overburden reported is the amount of rock above the stratigraphically highest coal bed in the zone. The resource numbers reported do not include coal within mine or lease areas, in areas containing mapped Wyodak-Anderson clinker, or in areas where the coal is extrapolated to be less than 2.5 ft thick. The resources of the Wyodak-Anderson coal zone are reported in Ellis and others (1998). A general description of how the resources were calculated is included in that report. The purpose of this report is to document in more detail some of the parameters and methods used, define our spatial data, compare resources calculated using different grid options and calculation methods, and explain the application of confidence limits to the resource calculation.

Negative pressure wound therapy for Gustilo Anderson grade IIIb open tibial fractures.

PubMed

Park, Chul Hyun; Shon, Oog Jin; Kim, Gi Beom

2016-09-01

Traditionally, Gustilo Anderson grade IIIb open tibial fractures have been treated by initial wide wound debridement, stabilization of fracture with external fixation, and delayed wound closure. The purpose of this study is to evaluate the clinical and radiological results of staged treatment using negative pressure wound therapy (NPWT) for Gustilo Anderson grade IIIb open tibial fractures. 15 patients with Gustilo Anderson grade IIIb open tibial fractures, treated using staged protocol by a single surgeon between January 2007 and December 2011 were reviewed in this retrospective study. The clinical results were assessed using a Puno scoring system for severe open fractures of the tibia at the last followup. The range of motion (ROM) of the knee and ankle joints and postoperative complication were evaluated at the last followup. The radiographic results were assessed using time to bone union, coronal and sagittal angulations and a shortening at the last followup. The mean score of Puno scoring system was 87.4 (range 67-94). The mean ROM of the knee and ankle joints was 121.3° (range 90°-130°) and 37.7° (range 15°-50°), respectively. Bone union developed in all patients and the mean time to union was 25.3 weeks (range 16-42 weeks). The mean coronal angulation was 2.1° (range 0-4°) and sagittal was 2.7° (range 1-4°). The mean shortening was 4.1 mm (range 0-8 mm). Three patients had partial flap necrosis and 1 patient had total flap necrosis. There was no superficial and deep wound infection. Staged treatment using NPWT decreased the risks of infection and requirement of flap surgeries in Gustilo Anderson grade IIIb open tibial fractures. Therefore, staged treatment using NPWT could be a useful treatment option for Gustilo Anderson grade IIIb open tibial fractures.

Scaling theory of tunneling diffusion of a heavy particle interacting with phonons

NASA Astrophysics Data System (ADS)

Itai, K.

1988-05-01

The author discusses motion of a heavy particle in a d-dimensional lattice interacting with phonons by different couplings. The models discussed are characterized by the dimension (d) and the set of two indices (λ,ν) which specify the momentum dependence of the dispersion of phonon energy (ω~kν) and of the particle-phonon coupling (~kλ). Scaling equations are derived by eliminating the short-time behavior in a renormalization-group scheme using Feynman's path-integral method, and the technique developed by Anderson, Yuval, and Hamann for the Kondo problem. The scaling equations show that the particle is localized in the strict sense when (2λ+d+2)/ν<2 and is not localized when (2λ+d+2)/ν>2. In the marginal case, i.e., (2λ+d+2)/ν=2, localization occurs for couplings larger than a critical value. This marginal case shows Ohmic dissipation and is a close analogy to the Caldeira-Leggett model for macroscopic quantum tunneling and the hopping models of Schmid's type. For large-enough (2λ+d+2)/ν, the particle is considered practically localized, but the origin of the localization is quite different from that for (2λ+d+2)/ν<=2. .AE

Local differences in parasitism and competition shape defensive investment in a polymorphic eusocial bee.

PubMed

Segers, Francisca H I D; von Zuben, Lucas; Grüter, Christoph

2016-02-01

Many colonial animals rely for their defense on a soldier caste. Adaptive colony demography theory predicts that colonies should flexibly adjust the investment in different worker castes depending on the colony needs. For example, colonies should invest more in defensive workers (e.g., soldiers) in dangerous environments. However, evidence for this prediction has been mixed. We combined descriptive and experimental approaches to examine whether defensive investment and worker size are adjusted to local ecology in the only known bee with polymorphic workers, Tetragonisca angustula. Colonies of this species are defended by a morphologically specialized soldier caste. Our study included three populations that differed in the density of food competition and the occurrence of a parasitic robber bee. We found that colonies coexisting with robber bees had on average 43% more soldiers defending the nest entrance, while colonies facing stronger foraging competition had soldiers that were -6-7% smaller. We then experimentally relocated colonies to areas with different levels of competition. When released from intense food competition, body sizes of guards and foragers increased. After introducing chemical robber bee cues at nest entrances, we found both a short-term and a long-term up-regulation of the number of soldiers defending the colony. Active soldier numbers remained high after the experiment for a duration equivalent to 2-3 worker life spans. How information about past parasite threat is stored in the colony is currently unknown. In summary, T. angustula adjusts both the number and the body size of active soldiers to local ecological conditions. Competitor density also affects forager (or minor) size, an important colony trait with potential community ecological consequences. Our study supports adaptive colony demography theory in a eusocial bee and highlights the importance of colony threats and competition as selective forces shaping colony phenotype.

Critical exponents of the disorder-driven superfluid-insulator transition in one-dimensional Bose-Einstein condensates

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

Cestari, J. C. C.; Foerster, A.; Gusmao, M. A.

2011-11-15

We investigate the nature of the superfluid-insulator quantum phase transition driven by disorder for noninteracting ultracold atoms on one-dimensional lattices. We consider two different cases: Anderson-type disorder, with local energies randomly distributed, and pseudodisorder due to a potential incommensurate with the lattice, which is usually called the Aubry-Andre model. A scaling analysis of numerical data for the superfluid fraction for different lattice sizes allows us to determine quantum critical exponents characterizing the disorder-driven superfluid-insulator transition. We also briefly discuss the effect of interactions close to the noninteracting quantum critical point of the Aubry-Andre model.

Solidification, growth mechanisms, and associated properties of aluminum-silicon and magnesium lightweight casting alloys

NASA Astrophysics Data System (ADS)

Hosch, Timothy Al

Continually rising energy prices have inspired increased interest in weight reduction in the automotive and aerospace industries, opening the door for the widespread use and development of lightweight structural materials. Chief among these materials are cast Al-Si and magnesium-based alloys. Utilization of Al-Si alloys depends on obtaining a modified fibrous microstructure in lieu of the intrinsic flake structure, a process which is incompletely understood. The local solidification conditions, mechanisms, and tensile properties associated with the flake to fiber growth mode transition in Al-Si eutectic alloys are investigated here using bridgman type gradient-zone directional solidification. Resulting microstructures are examined through quantitative image analysis of two-dimensional sections and observation of deep-etched sections showing three-dimensional microstructural features. The transition was found to occur in two stages: an initial stage dominated by in-plane plate breakup and rod formation within the plane of the plate, and a second stage where the onset of out-of-plane silicon rod growth leads to the formation of an irregular fibrous structure. Several microstructural parameters were investigated in an attempt to quantify this transition, and it was found that the particle aspect ratio is effective in objectively identifying the onset and completion velocity of the flake to fiber transition. The appearance of intricate out-of-plane silicon instability formations was investigated by adapting a perturbed-interface stability analysis to the Al-Si system. Measurements of silicon equilibrium shape particles provided an estimate of the anisotropy of the solid Si/liquid Al-Si system and incorporation of this silicon anisotropy into the model was found to improve prediction of the instability length scale. Magnesium alloys share many of the benefits of Al-Si alloys, with the added benefit of a 1/3 lower density and increased machinability. Magnesium castings often contain additions of heavier elements, such as zinc, zirconium, and rare earth elements, which significantly improve high temperature performance. However, additions of these elements can lead to macrosegregational effects in castings, which are detectable by radiographic scans. The effect of these flow-line indications on alloy mechanical properties is not well quantified. An examination of these flow-line indications and their effects on mechanical properties in three magnesiumbased casting alloys was performed here in order to determine the best practice for dealing with affected castings. Preliminary results suggest the flow-lines do not measurably impact bulk material properties. Three additional methods of characterizing three-dimensional material structures are also presented: a minimum spanning tree analysis is utilized to quantify local structure in Cu-Zr liquid phase simulations obtained from molecular dynamics; the radial distribution function is applied to directionally solidified Al-Si structures in an attempt to extract local spacing data; and the critical diameter measurement is also defined and applied to irregular eutectic Al-Si structures.

"Be the Tree": Classical Literature, Art Therapy, and Transcending Trauma in "Speak"

ERIC Educational Resources Information Center

Snider, Jessi

2014-01-01

Laurie Halse Anderson's young adult novel "Speak" concerns the rape and subsequent silence of ninth grade protagonist Melinda Sordino. By relying on extensive literary allusions involving trees, rape, silence, and transformation, Anderson creates a young adult problem novel that is both of the moment and timeless in its themes. The…

Combining Anderson's Model in the Teaching of Art Appreciation for Undergraduate Students

ERIC Educational Resources Information Center

Subramaniam, Maithreyi; Basaree, Ruzaika Omar; Hanafi, Jaffri; Putih, Abu Talib

2016-01-01

This study utilized 33 students taking creative communication design 3 in the third year of the graphic design and multimedia program, using an Anderson's model in teaching art appreciation. The quantitative research design and procedures were employed in this study. An experimental research using the quasi-experimental design, a single-group…

71. Transmitter building no. 102, view of arrangement showing the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

71. Transmitter building no. 102, view of arrangement showing the Klystron tube vaults along right side of photograph and capacitor vaults along left side of photograph. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Narratives as Dialogic, Contested, and Aesthetic Performances

ERIC Educational Resources Information Center

Harter, Lynn M.

2009-01-01

Dr. Pete Anderson, a clinician and professor at the University of Texas MD Anderson Cancer Center, entered the life of Anna and her family two years ago. Anna was referred to him because of his clinical research and expertise in pediatric oncology and multimodality therapies. Anna had been diagnosed with metastatic Ewing's Sarcoma, a form of bone…

2. View of southerly DR 1 antenna looking north 25 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. View of southerly DR 1 antenna looking north 25 degrees west and and showing radar scanner building no. 105 east face through antenna. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

3. View of middle DR 2 antenna looking north 30 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. View of middle DR 2 antenna looking north 30 degrees west and showing radar scanner building no. 105 east face through antenna. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Design Calculation Procedure for Passive Solar Houses at Navy Installations in East Coast Regions with Temperate Climate. Volume II.

DTIC Science & Technology

1981-10-01

READING 17. Rick Fisher and Bill Yanda, Solar Greenhouse, John Muir Publications, Santa Fe, NM 87501, 1976. 18. 0. A. Bainbridge, "Water Wall Passive...Anderson and Michael Riordan , The Solar House Book, Chesire Books, Harrisville, New Hampshire, 1976. 24. Bruce Anderson, Solar Energy: Fundamentals in

E. N. Anderson: Caring for place: ecology, ideology, and emotion in traditional landscape management

Treesearch

Susan Stevens Hummel

2016-01-01

Anderson is deeply concerned with inadequate responses to ongoing global environmental degradation. Accordingly, he offers cases of traditional societies that survived over long time periods without destroying their environments. His focus is on ways humans think about plants, animals, and landscapes because of his conviction that stories about them are what make us...

75 FR 69160 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-10

... Anderson John Derek Anderson Rose Mary Andreen Clas Svante Joel Ang Diana Shu-Zhen Angelini Kevin Yang... Anthony Bergandi Marco Lee Berre Jean N. Berryman Curtis Frederick Beveridge Richard Henry Earle Beveridge... Cheung Mark Quintin Chih-Hsiang Lisa Lee Chiu Sammy Kai-Kong Christianson Marlys Chun Jessica Chung...

43. View of CSMR room equipment locator and system checkout ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

43. View of CSMR room equipment locator and system checkout console for detection radars and rearward communication data links in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

9. View of back side of radar scanner building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. View of back side of radar scanner building no. 106 showing passageway links to other buildings east and west, and DR 3 antenna in background. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

10. View of back side of radar scanner building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. View of back side of radar scanner building no. 104 showing passageway links to other building to east and DR 1 antenna in background. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

50. View of waveguides beginning to move toward two radar ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. View of waveguides beginning to move toward two radar scanner switches (two per radar scanner building) by vertical bends; also tuning devices are located here. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

21. View from south to southerly face of scanner building ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. View from south to southerly face of scanner building 104 showing building radius. Radius of building face matches radius of DR antenna systems. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

18. View from DR 2 antenna looking south 45 degrees ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. View from DR 2 antenna looking south 45 degrees west to backside transmitter building 101 and in left foreground showing site well system building. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

20. View from northeast to southwest side of scanner building ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. View from northeast to southwest side of scanner building 104 showing two waveguide termination faces (fiberglass light bands on left of photograph). - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

46. Building 102, view showing waveguide control switch used to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

46. Building 102, view showing waveguide control switch used to achieve equal length adjustments and frequency control between separate Klystron tube radion frequency (RF) generators. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Comments in defense of symposia proceedings: Response to Bart and Anderson

Treesearch

Deborah M. Finch; A. Lorin Ward; R. H. Hamre

1982-01-01

A recent "Opinion" in the Wildlife Society Bulletin (Bart and Anderson 1981) made a case against publishing symposia proceedings because (1) papers of non-refereed symposia often lack credibility and, therefore, harm both the authors and the profession, (2) proceedings are not readily retrievable, and (3) some symposium reports are not appropriate for...

32. View of relay assembly group and interconnecting group electronic ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. View of relay assembly group and interconnecting group electronic modules located on second floor of transmitter building no. 102 in MIP area. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

85. View of specialized maintenance shop in transmitter building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

85. View of specialized maintenance shop in transmitter building no. 101, showing test bed with meters, power supplies, oscilloscopes, and other electronic test equipment. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

35. View of data and analysis console (DAC), located in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. View of data and analysis console (DAC), located in MWOC facility in transmitter building no. 102, showing clock and missile impact predictor time. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Dystopian Visions of Global Capitalism: Philip Reeve's "Mortal Engines" and M.T Anderson's "Feed"

ERIC Educational Resources Information Center

Bullen, Elizabeth; Parsons, Elizabeth

2007-01-01

This article examines Philip Reeve's novel for children, "Mortal Engines", and M.T. Anderson's young adult novel, "Feed", by assessing these dystopias as prototypical texts of what Ulrich Beck calls risk society. Through their visions of a fictional future, the two narratives explore the hazards created by contemporary techno-economic progress,…

Breakthrough: Lead-free Solder

ScienceCinema

Anderson, Iver

2018-05-07

Ames Laboratory senior metallurgist Iver Anderson explains the importance of lead-free solder in taking hazardous lead out of the environment by eliminating it from discarded computers and electronics that wind up in landfills. Anderson led a team that developed a tin-silver-copper replacement for traditional lead-tin solder that has been adopted by more than 50 companies worldwide.

39. View of checkout indicator computer console for DR beams, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

39. View of checkout indicator computer console for DR beams, TR chains, and special checkout target control located in CSMR in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

First progress report, 1961-1962, cooperative watershed management in the lower conifer zone of California

Treesearch

Walt Hopkins; Kenneth L. Boden

1962-01-01

The job of watershed management research is to conduct studies which will suggest better methods of management for water and predict the effects of a wide span of land management practices upon streamflow, water yield, and sedimentation. A program for watershed management research was prepared by Henry Anderson in 1960 (Anderson, 1960).

A Response and Commentary To: A Review of e-Learning in Canada

ERIC Educational Resources Information Center

Anderson, Terry

2006-01-01

Terry Anderson is a professor and Canada Research chair in Distance Education at Athabasca University, Canada's Open University, where he teaches in the Masters of Distance Education program. In this article, Anderson begins his response to "A Review of E-Learning in Canada" by commenting that he believes Philip Abrami and his colleagues…

73. View of line of stainless steel coolant storage tanks ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

73. View of line of stainless steel coolant storage tanks for bi-sodium sulfate/water coolant solution at first floor of transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

106. Air defense command "master plan", base map," RCA Service ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

106. Air defense command "master plan", base map," RCA Service Company tab no. F-1, sheet 1 of 2, dated 22 October, 1965. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

107. Air defense command "master plan, basic mission plan," RCA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

107. Air defense command "master plan, basic mission plan," RCA Service Company tab no. F-1, sheet 2 of 2, dated 1 June, 1963. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

FBI Attempt to Screen Archive Prompts Fears: Journalist's Family Wants to Block Search of Papers Held by University

ERIC Educational Resources Information Center

Carlson, Scott

2006-01-01

During his life and career as a muckraking journalist in Washington, Jack Anderson cultivated secret sources throughout the halls of government--sources who passed on information that allowed Anderson to investigate and write about Watergate, CIA assassination schemes, and countless scandals. His syndicated column, Washington Merry-Go-Round,…

(dis)Ability and Music Education: Paralympian Patrick Anderson and the Experience of Disability in Music

ERIC Educational Resources Information Center

Bell, Adam Patrick

2017-01-01

What does it mean to experience disability in music? Based on interviews with Patrick Anderson--arguably the greatest wheelchair basketball player of all time--this article presents insights into the complexities of the experience of disability in sports and music. Contrasted with music education's tendency to adhere to a medicalized model of…

A Safe School Climate: A Systemic Approach and the School Counselor

ERIC Educational Resources Information Center

Hernandez, Thomas J.; Seem, Susan R.

2004-01-01

The climate of the school is central to the educational mission of a school (Anderson, 1998; Sherman et al., 1997; Jenkins, 1997; Lockwood, 1997). Anderson surveyed recent school safety research and found that altering a school's internal climate can have a significant positive effect on the feeling of safety in the school community. Gottfredson…

View of Expedition 15 FE Anderson performing the ANITA Experiment in the Node 1

NASA Image and Video Library

2007-10-06

ISS015-E-32200 (6 Oct. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, uses an air sample pump and 2.5 liter gas sample bag to gather and analyze air samples for the Analyzing Interferometer for Ambient Air (ANITA) experiment in the Unity node of the International Space Station.

59. View of high voltage (4160 volts alternating current) electric ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

59. View of high voltage (4160 volts alternating current) electric load center and motor control center at mezzanine level in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

105. View of tracking radome replacement project, progress photograph, official ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

105. View of tracking radome replacement project, progress photograph, official photograph BMEWS Project by unknown photographer, 11 August 1981, clear as negative no. A-18562. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

75 FR 16177 - Notice of Lodging of Material Modification to Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-31

... the State of Indiana v. City of Anderson, Indiana, Civil Action No. IP 02- 1103 C M/S (S.D. Ind.) was... Anderson, Indiana, Civil Action No. IP 02-1103 C M/S (S.D. Ind.) and D.J. Ref. No. 90-5-2-1-07043/2. The...

A Short History of the Theory and Experimental Discovery of Superfluidity in 3He

NASA Astrophysics Data System (ADS)

Brinkman, W. F.

I discuss the development of the theory and experiments on superfluid 3He. After the discovery of superfluidity in 3He by Osheroff, Richardson and Lee, Phil Anderson quickly recruited Doug Osheroff to come to Bell Labs and set up a dilution fridge to continue his experiments. One of the mysteries at that time was how the high-temperature A-phase, which has a gapless excitation spectrum, could be stabilized relative to the fully gapped, lower temperature B-phase. I explain how Phil Anderson and I developed the spin fluctuation theory of the A-phase of superfluid 3He which accounted for its stability, leading to the Anderson-Brinkman-Morel (ABM) theory of the superfluid A-phase...

Sodium bicarbonate loading limits tubular cast formation independent of glomerular injury and proteinuria in dahl salt-sensitive rats.

PubMed

Ray, S C; Patel, B; Irsik, D L; Sun, J; Ocasio, H; Crislip, G R; Jin, C H; Chen, J K; Baban, B; Polichnowski, A J; O'Connor, P M

2018-04-12

Sodium bicarbonate (NaHCO 3 ) slows the decline in kidney function in patients with chronic kidney disease (CKD), yet the mechanisms mediating this effect remain unclear. The Dahl salt-sensitive (SS) rat develops hypertension and progressive renal injury when fed a high salt diet; however, the effect of alkali loading on kidney injury has never been investigated in this model. We hypothesized that 'NaHCO 3 protects from the development of renal injury in Dahl salt-sensitive rats via luminal alkalization which limits the formation of tubular casts, which are a prominent pathological feature in this model. To examine this hypothesis, we determined blood pressure and renal injury responses in Dahl SS rats drinking vehicle (0.1M NaCl) or NaHCO 3 (0.1M) solutions as well as in Dahl SS rats lacking the voltage gated proton channel (Hv1). We found that oral NaHCO 3 reduced tubular NH 4 + production, tubular cast formation and interstitial fibrosis in rats fed a high salt diet for 2 weeks. This effect was independent of changes in blood pressure, glomerular injury or proteinuria and did not associate with changes in renal inflammatory status. We found that null mutation of Hv1 also limited cast formation in Dahl SS rats independent of proteinuria or glomerular injury. As Hv1 is localized to the luminal membrane of TAL, our data, suggest that alkalization of the luminal fluid within this segment limits cast formation in this model. Reduced cast formation, secondary to luminal alkalization within TAL segments may mediate some of the protective effects of alkali loading observed in CKD patients. ©2018 The Author(s).

Population differentiation of southern Indian male lineages correlates with agricultural expansions predating the caste system.

PubMed

Arunkumar, Ganeshprasad; Soria-Hernanz, David F; Kavitha, Valampuri John; Arun, Varatharajan Santhakumari; Syama, Adhikarla; Ashokan, Kumaran Samy; Gandhirajan, Kavandanpatti Thangaraj; Vijayakumar, Koothapuli; Narayanan, Muthuswamy; Jayalakshmi, Mariakuttikan; Ziegle, Janet S; Royyuru, Ajay K; Parida, Laxmi; Wells, R Spencer; Renfrew, Colin; Schurr, Theodore G; Smith, Chris Tyler; Platt, Daniel E; Pitchappan, Ramasamy

2012-01-01

Previous studies that pooled Indian populations from a wide variety of geographical locations, have obtained contradictory conclusions about the processes of the establishment of the Varna caste system and its genetic impact on the origins and demographic histories of Indian populations. To further investigate these questions we took advantage that both Y chromosome and caste designation are paternally inherited, and genotyped 1,680 Y chromosomes representing 12 tribal and 19 non-tribal (caste) endogamous populations from the predominantly Dravidian-speaking Tamil Nadu state in the southernmost part of India. Tribes and castes were both characterized by an overwhelming proportion of putatively Indian autochthonous Y-chromosomal haplogroups (H-M69, F-M89, R1a1-M17, L1-M27, R2-M124, and C5-M356; 81% combined) with a shared genetic heritage dating back to the late Pleistocene (10-30 Kya), suggesting that more recent Holocene migrations from western Eurasia contributed <20% of the male lineages. We found strong evidence for genetic structure, associated primarily with the current mode of subsistence. Coalescence analysis suggested that the social stratification was established 4-6 Kya and there was little admixture during the last 3 Kya, implying a minimal genetic impact of the Varna (caste) system from the historically-documented Brahmin migrations into the area. In contrast, the overall Y-chromosomal patterns, the time depth of population diversifications and the period of differentiation were best explained by the emergence of agricultural technology in South Asia. These results highlight the utility of detailed local genetic studies within India, without prior assumptions about the importance of Varna rank status for population grouping, to obtain new insights into the relative influences of past demographic events for the population structure of the whole of modern India.

Bulk critical state and fundamental length scales of superconducting nanocrystalline Nb3Al in Nb-Al matrix

NASA Astrophysics Data System (ADS)

Mondal, Puspen; Manekar, Meghmalhar; Srivastava, A. K.; Roy, S. B.

2009-07-01

We present the results of magnetization measurements on an as-cast nanocrystalline Nb3Al superconductor embedded in Nb-Al matrix. The typical grain size of Nb3Al ranges from about 2-8 nm with the maximum number of grains at around 3.5 nm, as visualized using transmission electron microscopy. The isothermal magnetization hysteresis loops in the superconducting state can be reasonably fitted within the well-known Kim-Anderson critical-state model. By using the same fitting parameters, we calculate the variation in field with respect to distance inside the sample and show the existence of a critical state over length scales much larger than the typical size of the superconducting grains. Our results indicate that a bulk critical current is possible in a system comprising of nanoparticles. The nonsuperconducting Nb-Al matrix thus appears to play a major role in the bulk current flow through the sample. The superconducting coherence length ξ is estimated to be around 3 nm, which is comparable to the typical grain size. The penetration depth λ is estimated to be about 94 nm, which is much larger than the largest of the superconducting grains. Our results could be useful for tuning the current carrying capability of conductors made out of composite materials which involve superconducting nanoparticles.

Fatigue-Induced Damage in Zr-Based Bulk Metallic Glasses

PubMed Central

Chuang, Chih-Pin; Yuan, Tao; Dmowski, Wojciech; Wang, Gong-Yao; Freels, Matt; Liaw, Peter K.; Li, Ran; Zhang, Tao

2013-01-01

In the present work, we investigate the effect of “fatigue” on the fatigue behavior and atomic structure of Zr-based BMGs. Fatigue experiments on the failed-by-fatigue samples indicate that the remnants generally have similar or longer fatigue life than the as-cast samples. Meanwhile, the pair-distribution-function (PDF) analysis of the as-cast and post-fatigue samples showed very small changes of local atomic structures. These observations suggest that the fatigue life of the 6-mm in-diameter Zr-based BMG is dominated by the number of pre-existing crack-initiation sites in the sample. Once the crack initiates in the specimen, the fatigue-induced damage is accumulated locally on these initiated sites, while the rest of the region deforms elastically. The results suggest that the fatigue failure of BMGs under compression-compression fatigue experiments is a defect-controlled process. The present work indicates the significance of the improved fatigue resistance with decreasing the sample size. PMID:23999496

Tensile fracture of coarse-Grained cast austenitic manganese steels

NASA Astrophysics Data System (ADS)

Rittel, D.; Roman, I.

1988-09-01

Tensile fracture of coarse-grained (0.25 to 1 mm) cast austenitic manganese (Hadfield) steels has been investigated. Numerous surface discontinuities nucleate in coarse slip bands, on the heavily deformed surface of tensile specimens. These discontinuities do not propagate radially and final fracture results from central specimen cracking at higher strains. On the microscopic scale, bulk voids nucleate during the entire plastic deformation and they do not coalesce by shear localization (e.g., void-sheet) mechanism. Close voids coalesce by internal necking, whereas distant voids are bridged by means of small voids which nucleate at later stages of the plastic deformation. The high toughness of Hadfield steels is due to their high strain-hardening capacity which stabilizes the plastic deformation, and avoids shear localization and loss of load-bearing capacity. The observed dependence of measured mechanical properties on the specimen’s geometry results from the development of a surface layer which charac-terizes the deformation of this coarse-grained material.

Quantitative evaluation of hidden defects in cast iron components using ultrasound activated lock-in vibrothermography.

PubMed

Montanini, R; Freni, F; Rossi, G L

2012-09-01

This paper reports one of the first experimental results on the application of ultrasound activated lock-in vibrothermography for quantitative assessment of buried flaws in complex cast parts. The use of amplitude modulated ultrasonic heat generation allowed selective response of defective areas within the part, as the defect itself is turned into a local thermal wave emitter. Quantitative evaluation of hidden damages was accomplished by estimating independently both the area and the depth extension of the buried flaws, while x-ray 3D computed tomography was used as reference for sizing accuracy assessment. To retrieve flaw's area, a simple yet effective histogram-based phase image segmentation algorithm with automatic pixels classification has been developed. A clear correlation was found between the thermal (phase) signature measured by the infrared camera on the target surface and the actual mean cross-section area of the flaw. Due to the very fast cycle time (<30 s/part), the method could potentially be applied for 100% quality control of casting components.

Mathematical Model of Solidification During Electroslag Casting of Pilger Roll

NASA Astrophysics Data System (ADS)

Liu, Fubin; Li, Huabing; Jiang, Zhouhua; Dong, Yanwu; Chen, Xu; Geng, Xin; Zang, Ximin

A mathematical model for describing the interaction of multiple physical fields in slag bath and solidification process in ingot during pilger roll casting with variable cross-section which is produced by the electroslag casting (ESC) process was developed. The commercial software ANSYS was applied to calculate the electromagnetic field, magnetic driven fluid flow, buoyancy-driven flow and heat transfer. The transportation phenomenon in slag bath and solidification characteristic of ingots are analyzed for variable cross-section with variable input power under the conditions of 9Cr3NiMo steel and 70%CaF2 - 30%Al2O3 slag system. The calculated results show that characteristic of current density distribution, velocity patterns and temperature profiles in the slag bath and metal pool profiles in ingot have distinct difference at variable cross-sections due to difference of input power and cooling condition. The pool shape and the local solidification time (LST) during Pilger roll ESC process are analyzed.

Magnetically assisted slip casting of bioinspired heterogeneous composites

NASA Astrophysics Data System (ADS)

Le Ferrand, Hortense; Bouville, Florian; Niebel, Tobias P.; Studart, André R.

2015-11-01

Natural composites are often heterogeneous to fulfil functional demands. Manufacturing analogous materials remains difficult, however, owing to the lack of adequate and easily accessible processing tools. Here, we report an additive manufacturing platform able to fabricate complex-shaped parts exhibiting bioinspired heterogeneous microstructures with locally tunable texture, composition and properties, as well as unprecedentedly high volume fractions of inorganic phase (up to 100%). The technology combines an aqueous-based slip-casting process with magnetically directed particle assembly to create programmed microstructural designs using anisotropic stiff platelets in a ceramic, metal or polymer functional matrix. Using quantitative tools to control the casting kinetics and the temporal pattern of the applied magnetic fields, we demonstrate that this approach is robust and can be exploited to design and fabricate heterogeneous composites with thus far inaccessible microstructures. Proof-of-concept examples include bulk composites with periodic patterns of microreinforcement orientation, and tooth-like bilayer parts with intricate shapes exhibiting site-specific composition and texture.

Self-trapping of the amide I band in a peptide model crystal

NASA Astrophysics Data System (ADS)

Edler, J.; Hamm, P.

2002-08-01

A femtosecond pump-probe study of the peculiar amide I band of acetanilide, a molecular crystal with hydrogen bonded chains of peptide units, is presented. The almost perfect harmonicity of the 1666 cm-1 subpeak is related to significant delocalization of this state at low enough temperatures (93 K). The "anomalous" peak (1650 cm-1), on the other hand, is strongly anharmonic, and hence assigned to a self-trapped state. This assignment is in agreement with a more indirect previous work. With increasing temperature, thermal disorder localizes the 1666 cm-1 band (Anderson localization) and at the same time destroys the self-trapping mechanism. Both the self-trapped state and the delocalized state decay on a 2 ps time scale into states outside the spectral window of this study. The excitation energy reappears on a much slower 35 ps time scale in the form of an increased lattice temperature.

Driving a Superconductor to Insulator Transition with Random Gauge Fields.

PubMed

Nguyen, H Q; Hollen, S M; Shainline, J; Xu, J M; Valles, J M

2016-11-30

Typically the disorder that alters the interference of particle waves to produce Anderson localization is potential scattering from randomly placed impurities. Here we show that disorder in the form of random gauge fields that act directly on particle phases can also drive localization. We present evidence of a superfluid bose glass to insulator transition at a critical level of this gauge field disorder in a nano-patterned array of amorphous Bi islands. This transition shows signs of metallic transport near the critical point characterized by a resistance , indicative of a quantum phase transition. The critical disorder depends on interisland coupling in agreement with recent Quantum Monte Carlo simulations. We discuss how this disorder tuned SIT differs from the common frustration tuned SIT that also occurs in magnetic fields. Its discovery enables new high fidelity comparisons between theoretical and experimental studies of disorder effects on quantum critical systems.

Proposal for a new trajectory for subaxial cervical lateral mass screws.

PubMed

Amhaz-Escanlar, Samer; Jorge-Mora, Alberto; Jorge-Mora, Teresa; Febrero-Bande, Manuel; Diez-Ulloa, Maximo-Alberto

2018-06-20

Lateral mass screws combined with rods are the standard method for posterior cervical spine subaxial fixation. Several techniques have been described, among which the most used are Roy Camille, Magerl, Anderson and An. All of them are based on tridimensional angles. Reliability of freehand angle estimation remains poorly investigated. We propose a new technique based on on-site spatial references and compare it with previously described ones assessing screw length and neurovascular potential complications. Four different lateral mass screw insertion techniques (Magerl, Anderson, An and the new described technique) were performed bilaterally, from C3 to C6, in ten human spine specimens. A drill tip guide wire was inserted as originally described for each trajectory, and screw length was measured. Exit point was examined, and potential vertebral artery or nerve root injury was assessed. Mean screw length was 14.05 mm using Magerl's technique, 13.47 mm using Anderson's, 12.8 mm using An's and 17.03 mm using the new technique. Data analysis showed significantly longer lateral mass screw length using the new technique (p value < 0.00001). Nerve potential injury occurred 37 times using Magerl's technique, 28 using Anderson's, 13 using An's and twice using the new technique. Vertebral artery potential injury occurred once using Magerl's technique, 8 times using Anderson's and none using either An's or the new proposed technique. The risk of neurovascular complication was significantly lower using the new technique (p value < 0.01). The new proposed technique allows for longer screws, maximizing purchase and stability, while lowering the complication rate.

Progress towards measurement of entanglement entropy dynamics in one-dimensional interacting systems in the presence of disorder

NASA Astrophysics Data System (ADS)

Lukin, Alexander; Tai, M. Eric; Rispoli, Matthew; Schittko, Robert; Menke, Tim; Kaufman, Adam; Greiner, Markus

2017-04-01

Many-body localized states appear at odds with thermalization as they preserve the memory of their initial state. This behavior has drawn significant theoretical and experimental attention in recent years. Real space localization has been observed on various platforms and under a number of experimental conditions, both with and without interactions. However, the characteristic logarithmic growth of entanglement entropy, which distinguishes the many-body localized state from the non-interacting Anderson localized state, has only been studied in numerics and has yet to be investigated experimentally. We are working towards the phenomenon of localization in one dimensional, interacting Bose-Hubbard system using a quantum gas microscope. With site-resolved addressing and readout, our microscope provides full control over the studied system, in particular it allows us to add disorder into our system using a Fourier plane hologram. This gives us access to both local observables, such as the occupation of individual lattice sites, as well as the entanglement entropy. I will present our progress towards measuring the dependence of the entanglement entropy grows on the disorder strength and interactions in our system. National Science Foundation, Gordon and Betty Moore Foundation's EPiQS Initiative, Air Force Office of Scientific Research MURI program, NSF Graduate Research Fellowship Program (MNR).

Localization of phonons in mass-disordered alloys: A typical medium dynamical cluster approach

DOE PAGES

Jarrell, Mark; Moreno, Juana; Raja Mondal, Wasim; ...

2017-07-20

The effect of disorder on lattice vibrational modes has been a topic of interest for several decades. In this article, we employ a Green's function based approach, namely, the dynamical cluster approximation (DCA), to investigate phonons in mass-disordered systems. Detailed benchmarks with previous exact calculations are used to validate the method in a wide parameter space. An extension of the method, namely, the typical medium DCA (TMDCA), is used to study Anderson localization of phonons in three dimensions. We show that, for binary isotopic disorder, lighter impurities induce localized modes beyond the bandwidth of the host system, while heavier impuritiesmore » lead to a partial localization of the low-frequency acoustic modes. For a uniform (box) distribution of masses, the physical spectrum is shown to develop long tails comprising mostly localized modes. The mobility edge separating extended and localized modes, obtained through the TMDCA, agrees well with results from the transfer matrix method. A reentrance behavior of the mobility edge with increasing disorder is found that is similar to, but somewhat more pronounced than, the behavior in disordered electronic systems. Our work establishes a computational approach, which recovers the thermodynamic limit, is versatile and computationally inexpensive, to investigate lattice vibrations in disordered lattice systems.« less

Localization of phonons in mass-disordered alloys: A typical medium dynamical cluster approach

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

Jarrell, Mark; Moreno, Juana; Raja Mondal, Wasim

The effect of disorder on lattice vibrational modes has been a topic of interest for several decades. In this article, we employ a Green's function based approach, namely, the dynamical cluster approximation (DCA), to investigate phonons in mass-disordered systems. Detailed benchmarks with previous exact calculations are used to validate the method in a wide parameter space. An extension of the method, namely, the typical medium DCA (TMDCA), is used to study Anderson localization of phonons in three dimensions. We show that, for binary isotopic disorder, lighter impurities induce localized modes beyond the bandwidth of the host system, while heavier impuritiesmore » lead to a partial localization of the low-frequency acoustic modes. For a uniform (box) distribution of masses, the physical spectrum is shown to develop long tails comprising mostly localized modes. The mobility edge separating extended and localized modes, obtained through the TMDCA, agrees well with results from the transfer matrix method. A reentrance behavior of the mobility edge with increasing disorder is found that is similar to, but somewhat more pronounced than, the behavior in disordered electronic systems. Our work establishes a computational approach, which recovers the thermodynamic limit, is versatile and computationally inexpensive, to investigate lattice vibrations in disordered lattice systems.« less

Association of Small Computer Users in Education (ASCUE) Summer Conference Proceedings (29th, North Myrtle Beach, South Carolina, June 9-13, 1996).

ERIC Educational Resources Information Center

Smith, Peter, Ed.

Papers from a conference on small college computing issues are: "Ethics, Privacy, and Security in Higher Education Technology" (John A. Anderson); "Multimedia in the Classroom: Recollections After Two Years" (Stephen T. Anderson Sr.); "Creating a Computer Competency Requirement for Mary Washington College Students" (David J. Ayersman, Ernest C.…

Markovian Anderson Model: Bounds for the Rate of Propagation

NASA Astrophysics Data System (ADS)

Tcheremchantsev, Serguei

We consider the Anderson model in with potentials whose values at any site of the lattice are Markovian independent random functions of time. For solutions to the time-dependent Schrödinger equation we show under some conditions that with probability 1 where for d=1,2 and for .

Identification and Analysis of Learning Preferences of Mentally Ill Adults in Rehabilitative Psychosocial Therapy at the Anderson Mental Health Center.

ERIC Educational Resources Information Center

Newman, Michael K.

A study identified and analyzed the learning preferences of 17 seriously and chronically mentally ill adults participating in the rehabilitative psychosocial therapy program at the Toxaway Church Site of the Anderson Mental Health Center. Staff perceived as boring and unfocused the traditional treatment approach that relied mainly upon…

Monte Carlo method for magnetic impurities in metals

NASA Technical Reports Server (NTRS)

Hirsch, J. E.; Fye, R. M.

1986-01-01

The paper discusses a Monte Carlo algorithm to study properties of dilute magnetic alloys; the method can treat a small number of magnetic impurities interacting wiith the conduction electrons in a metal. Results for the susceptibility of a single Anderson impurity in the symmetric case show the expected universal behavior at low temperatures. Some results for two Anderson impurities are also discussed.

62. View of amplifiermodulator control system with power distribution panel ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

62. View of amplifier-modulator control system with power distribution panel on left, control power supply in middle, and amplifier modulator on right, second floor in transmitter building no. 102. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

University of Texas MD Anderson Cancer Center (UT-MDACC): Systematic Functional Annotation of Somatic Mutations in Cancer | Office of Cancer Genomics

Cancer.gov

The CTD2 Center at the University of Texas MD Anderson Cancer Center utilized a functional annotation of mutations and fusions found in human cancers using two cell models, Ba/F3 (murine pro-B suspension cells) and MCF10A (human non-tumorigenic mammary epithelial cells). Read the abstract

75. Transmitter building no. 102, view of typical radio frequency ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

75. Transmitter building no. 102, view of typical radio frequency switching group for lower antenna A & B and upper antenna A & B and MIP/MWOC automated interface cabinet. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

28. View of data test area for DR data take ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

28. View of data test area for DR data take off set operators panel and cabinet at second floor of transmitter building no. 102 in MIP area. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

16. View of east side of transmitter building no. 102 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. View of east side of transmitter building no. 102 looking south with TR radome in upper right of photograph and DR 2 antenna in left of photograph. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

55. View from ground level in building no. 105 showing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

55. View from ground level in building no. 105 showing lower radar scanner switch with eighty-eight 1-1/2" diameter copper ion return RF balance tube systems. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Frederic Joliot, Irene Curie and the Early History of the Positron (1932-33)

ERIC Educational Resources Information Center

Leone, Matteo; Robotti, Nadia

2010-01-01

As is well known, the positron was discovered in August 1932 by Carl Anderson while studying cloud chamber tracks left by cosmic rays. Far less known is the fact that a few months before Anderson's discovery, in April 1932, Frederic Joliot and Irene Curie had missed an opportunity to discover the positron during a nuclear physics experiment. One…

48. View of typical 90 degree elbow located at horizontal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

48. View of typical 90 degree elbow located at horizontal corner with output (to scanner radar system control switch) waveguide on top and return wave on bottom of photograph. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

10 CFR 8.2 - Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954. 8.2 Section 8.2 Energy NUCLEAR REGULATORY COMMISSION INTERPRETATIONS § 8.2... in Nuclear Energy 75 (1959). In the testimony before the Joint Committee last year, Professor Samuel...

117. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

117. Back side technical facilities S.R. radar transmitter & computer building no. 102, "building sections - sheet I" - architectural, AS-BLT AW 35-46-04, sheet 12, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

122. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

122. Back side technical facilities S.R. radar transmitter & computer building no. 102, section II "elevations & details" - structural, AS-BLT AW 35-46-04, sheet 73, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

118. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

118. Back side technical facilities S.R. radar transmitter & computer building no. 102, "building sections - sheet I" - architectural, AS-BLT AW 35-46-04, sheet 13, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

121. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

121. Back side technical facilities S.R. radar transmitter & computer building no. 102, section II "sections & elevations" - structural, AS-BLT AW 35-46-04, sheet 72, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

34. View of typical work station in transmitter building no. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. View of typical work station in transmitter building no. 102, second floor, with continental electronics "keying pulse line amplifier trigger pulse AM-3445/FPT9" cabinet at desk. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

67. Building 102, view of electronic switching amplifier (in retracted ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

67. Building 102, view of electronic switching amplifier (in retracted or open position) with video monitor mounted at top to monitor performance and condition of system in oil bath. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

68. Building 102, view of same system as in photograph ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

68. Building 102, view of same system as in photograph no. AK-30-A-67 except switching amplifier in closed position; note video cameras in foreground of photograph at bottom. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

10 CFR 8.2 - Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954. 8.2 Section 8.2 Energy NUCLEAR REGULATORY COMMISSION INTERPRETATIONS § 8.2... in Nuclear Energy 75 (1959). In the testimony before the Joint Committee last year, Professor Samuel...

University of Texas MD Anderson Cancer Center: Systematic Functional Annotation of Somatic Mutations in Cancer | Office of Cancer Genomics

Cancer.gov

The CTD2 Center at the University of Texas MD Anderson Cancer Center utilized a functional annotation of mutations and fusions found in human cancers using two cell models, Ba/F3 (murine pro-B suspension cells) and MCF10A (human non-tumorigenic mammary epithelial cells). Read the abstract

Reflections on the Reflecting Art Therapy Team in Education and Treatment

ERIC Educational Resources Information Center

Riley, Shirley

2004-01-01

The reflecting team has been a respected mode of therapeutic intervention since psychiatrist Tom Anderson first proposed the concept in 1985 (Anderson, 1991). The notion of a team observing the therapist conducting a session, the reflecting team reflecting on the session in the presence of the client (either behind a one-way mirror or in person),…

Electronic structure of vitamin B12 within the framework of the Haldane-Anderson impurity model

NASA Astrophysics Data System (ADS)

Kandemir, Zafer; Mayda, Selma; Bulut, Nejat

2015-03-01

We study the electronic structure of vitamin B12 (cyanocobalamine C63H88CoN14O14P) by using the framework of the multi-orbital single-impurity Haldane-Anderson model of a transition-metal impurity in a semiconductor host. Here, our purpose is to understand the many-body effects originating from the transition-metal impurity. In this approach, the cobalt 3 d orbitals are treated as the impurity states placed in a semiconductor host which consists of the rest of the molecule. The parameters of the resulting effective Haldane-Anderson model are obtained within the Hartree-Fock approximation for the electronic structure of the molecule. The quantum Monte Carlo technique is then used to calculate the one-electron and magnetic correlation functions of this effective Haldane-Anderson model for vitamin B12. We find that new states form inside the semiconductor gap due to the on-site Coulomb interaction at the impurity 3 d orbitals and that these states become the highest occupied molecular orbitals. In addition, we present results on the charge distribution and spin correlations around the Co atom. We compare the results of this approach with those obtained by the density-functional theory calculations.

Interactive high-resolution isosurface ray casting on multicore processors.

PubMed

Wang, Qin; JaJa, Joseph

2008-01-01

We present a new method for the interactive rendering of isosurfaces using ray casting on multi-core processors. This method consists of a combination of an object-order traversal that coarsely identifies possible candidate 3D data blocks for each small set of contiguous pixels, and an isosurface ray casting strategy tailored for the resulting limited-size lists of candidate 3D data blocks. While static screen partitioning is widely used in the literature, our scheme performs dynamic allocation of groups of ray casting tasks to ensure almost equal loads among the different threads running on multi-cores while maintaining spatial locality. We also make careful use of memory management environment commonly present in multi-core processors. We test our system on a two-processor Clovertown platform, each consisting of a Quad-Core 1.86-GHz Intel Xeon Processor, for a number of widely different benchmarks. The detailed experimental results show that our system is efficient and scalable, and achieves high cache performance and excellent load balancing, resulting in an overall performance that is superior to any of the previous algorithms. In fact, we achieve an interactive isosurface rendering on a 1024(2) screen for all the datasets tested up to the maximum size of the main memory of our platform.

FRAMING Linguistics: ``SEANCES"(!!!) Martin-Bradshaw-Siegel ``Buzzwordism, Bandwagonism, Sloganeering For:Fun, Profit, Survival, Ego": Rampant UNethics Sociological-DYSfunctionality!!!

NASA Astrophysics Data System (ADS)

Bradshaw, John; Siegel, E.

2010-03-01

``Sciences''/SEANCES(!!!) rampant UNethics!!! WITNESS: Yau v Perelman Poincare-conj.-pf. [Naser, NewYorker(8/06)]; digits log- law Siegel[AMS Nat.Mtg.(02)-Abs.973-60-124] inversion to ONLY BEQS: Newcomb(1881)<<

"Rejoicing in the Beauties of Nature": The Image of the Western Landscape during the Fur Trade

ERIC Educational Resources Information Center

Oman, Kerry R.

2009-01-01

While traveling along the Platte River on May 18, 1834, William Marshall Anderson stopped to pick up a human skull bleaching in the prairie sunlight. Anderson was from Louisville, Kentucky, and had been sent west by his physician to accompany a fur-trade caravan to the Rocky Mountains in hopes of regaining lost physical strength. He came west not…

Concepts and Methods of Measuring Productivity at the Organization Level

DTIC Science & Technology

1993-09-01

Interfaces, The Institute of Management Sciences, 1987. Anderson, D. et al., An Introduction to Management Science, West Publishing Co., 1991... to Management Science, West Publishing Co., 1991. Anthony, G. M., "IEs Measure Work, Write Standards for White Collar Workers at Financial...Plant Productivity Measure for ’High-Tech’ Manufacturing, Interfaces, The Institute of Management Sciences, 1987. Anderson, D. et al., An Introduction

2005 8th Annual Systems Engineering Conference. Volume 2, Wednesday Presentations

DTIC Science & Technology

2005-10-27

Acquisition Programs: An OSD Perspective, Col Warren Anderson, OUSD (AT&L) Defense Systems Implementation of Policy Requiring Systems Engineering Plans...Technical Excellence, Col Warren Anderson, OUSD (AT&L) Defense Systems Applying CMMI to System Safety, Mr. Tom Pfitzer, APT Research, Inc. System...to following pages for Tutorials Schedule) Buffett Lunch Tutorial Tracks (Please refer to following pages for Tutorials Schedule) Reception in

7. View of DR 3 antenna typical front stay concrete ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. View of DR 3 antenna typical front stay concrete showing embedment anchors, foundation steel base plate, vertical member with small diameter turnbuckles, antenna assembly in background, and story board for scale. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Development of a Blood-Based Biomarker Panel for Indeterminate Lung Nodules

DTIC Science & Technology

2016-09-01

Taguchi CONTRACTING ORGANIZATION: University of Texas MD Anderson Cancer Center Houston, TX 77030 REPORT DATE: September 2016 TYPE OF REPORT...PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER University of Texas MD Anderson Cancer Center Rene...protein, autoantibody and microRNA) to distinguish malignant lung nodules from benign lung nodules. We have so far assayed 20 protein markers, 122

120. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

120. Back side technical facilities S.R. radar transmitter & computer building no. 102, section II "foundation & first floor plan" - structural, AS-BLT AW 35-46-04, sheet 65, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

119. Back side technical facilities S.R. radar transmitter & computer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

119. Back side technical facilities S.R. radar transmitter & computer building no. 102, section I "tower plan, sections & details" - structural, AS-BLT AW 35-46-04, sheet 62, dated 23 January, 1961. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK