DEFF Research Database (Denmark)
Codello, Alessandro; Tonero, Alberto
2016-01-01
We present a simple and consistent way to compute correlation functions in interacting theories with nontrivial phase diagram. As an example we show how to consistently compute the four-point function in three dimensional Z2-scalar theories. The idea is to perform the path integral by weighting...... the momentum modes that contribute to it according to their renormalization group (RG) relevance, i.e. we weight each mode according to the value of the running couplings at that scale. In this way, we are able to encode in a loop computation the information regarding the RG trajectory along which we...
Nontrivial Berry phase in magnetic BaMnSb2 semimetal
Huang, Silu; Kim, Jisun; Shelton, W. A.; Plummer, E. W.; Jin, Rongying
2017-06-01
The subject of topological materials has attracted immense attention in condensed-matter physics because they host new quantum states of matter containing Dirac, Majorana, or Weyl fermions. Although Majorana fermions can only exist on the surface of topological superconductors, Dirac and Weyl fermions can be realized in both 2D and 3D materials. The latter are semimetals with Dirac/Weyl cones either not tilted (type I) or tilted (type II). Although both Dirac and Weyl fermions have massless nature with the nontrivial Berry phase, the formation of Weyl fermions in 3D semimetals require either time-reversal or inversion symmetry breaking to lift degeneracy at Dirac points. Here we demonstrate experimentally that canted antiferromagnetic BaMnSb2 is a 3D Weyl semimetal with a 2D electronic structure. The Shubnikov-de Hass oscillations of the magnetoresistance give nearly zero effective mass with high mobility and the nontrivial Berry phase. The ordered magnetic arrangement (ferromagnetic ordering in the ab plane and antiferromagnetic ordering along the c axis below 286 K) breaks the time-reversal symmetry, thus offering us an ideal platform to study magnetic Weyl fermions in a centrosymmetric material.
DEFF Research Database (Denmark)
Koch, Carsten Allan
This paper attempts to generalize findings of the traditional literature of transaction cost economics (Willamson, 1971, 1973, 1975, 1985; Ouchi, 1980; Williamson & Ouchi 1981) by introducing more general factors or variables. Two of the most important of these are that asset specificity is repla......This paper attempts to generalize findings of the traditional literature of transaction cost economics (Willamson, 1971, 1973, 1975, 1985; Ouchi, 1980; Williamson & Ouchi 1981) by introducing more general factors or variables. Two of the most important of these are that asset specificity...... is replaced by a more general condition, vulnerability, and that the so-called market failure condition is replaced by a condition called contractual non-triviality. Sufficient conditions for non-triviality are found in terms of specific set of values for the basic set of factors....
Weng, Yanqiu; Palesch, Yuko Y; DeSantis, Stacia M; Zhao, Wenle
2016-01-01
In Phase III clinical trials for life-threatening conditions, some serious but expected adverse events, such as early deaths or congestive heart failure, are often treated as the secondary or co-primary endpoint, and are closely monitored by the Data and Safety Monitoring Committee (DSMC). A naïve group sequential design (GSD) for such a study is to specify univariate statistical boundaries for the efficacy and safety endpoints separately, and then implement the two boundaries during the study, even though the two endpoints are typically correlated. One problem with this naïve design, which has been noted in the statistical literature, is the potential loss of power. In this article, we develop an analytical tool to evaluate this negative impact for trials with non-trivial safety event rates, particularly when the safety monitoring is informal. Using a bivariate binary power function for the GSD with a random-effect component to account for subjective decision-making in safety monitoring, we demonstrate how, under common conditions, the power loss in the naïve design can be substantial. This tool may be helpful to entities such as the DSMCs when they wish to deviate from the prespecified stopping boundaries based on safety measures.
Therapy Provider Phase Information
U.S. Department of Health & Human Services — The Therapy Provider Phase Information dataset is a tool for providers to search by their National Provider Identifier (NPI) number to determine their phase for...
Orbifolds, quantum cosmology, and nontrivial topology
International Nuclear Information System (INIS)
Fagundes, Helio V.; Vargas, Teofilo
2006-01-01
In order to include nontrivial topologies in the problem of quantum creation of a universe, it seems to be necessary to generalize the sum over compact, smooth 4-manifolds to a sum over finite-volume, compact 4-orbifolds. We consider in detail the case of a 4-spherical orbifold with a cone-point singularity. This allows for the inclusion of a nontrivial topology into the semiclassical path integral approach to quantum cosmology, in the context of a Robertson-Walker minisuperspace. (author)
Supersymmetric quantum mechanics: another nontrivial quantum superpotential
International Nuclear Information System (INIS)
Cervero, J.M.
1991-01-01
A nontrivial example of a quantum superpotential in the framework of supersymmetric quantum mechanics is constructed using integrable soliton-like functions. The model is shown to be fully solvable and some consequences regarding the physical properties of the model such as transparence and boundary effects are discussed. (orig.)
Slavnov-Taylor constraints for nontrivial backgrounds
International Nuclear Information System (INIS)
Binosi, D.; Quadri, A.
2011-01-01
We devise an algebraic procedure for the evaluation of Green's functions in SU(N) Yang-Mills theory in the presence of a nontrivial background field. In the ghost-free sector the dependence of the vertex functional on the background is shown to be uniquely determined by the Slavnov-Taylor identities in terms of a certain 1-PI correlator of the covariant derivatives of the ghost and the antighost fields. At nonvanishing background this amplitude is shown to encode the quantum deformations to the tree-level background-quantum splitting. The approach only relies on the functional identities of the model (Slavnov-Taylor identities, b-equation, antighost equation) and thus it is valid beyond perturbation theory, and, in particular, in a lattice implementation of the background field method. As an example of the formalism we analyze the ghost two-point function and the Kugo-Ojima function in an instanton background in SU(2) Yang-Mills theory, quantized in the background Landau gauge.
Nontrivial asymptotically nonfree gauge theories and dynamical unification of couplings
International Nuclear Information System (INIS)
Kubo, J.
1995-01-01
Evidence for the nontriviality of asymptotically nonfree (ANF) Yang-Mills theories is found on the basis of optimized perturbation theory. It is argued that these theories with matter couplings can be made nontrivial by means of the reduction of couplings, leading to the idea of the dynamical unification of couplings (DUC). The second-order reduction of couplings in the ANF SU(3)-gauged Higgs-Yukawa theory, which is assumed to be nontrivial here, is carried out to motivate independent investigations on its nontriviality and DUC
Incomplete information and fractal phase space
International Nuclear Information System (INIS)
Wang, Qiuping A.
2004-01-01
The incomplete statistics for complex systems is characterized by a so called incompleteness parameter ω which equals unity when information is completely accessible to our treatment. This paper is devoted to the discussion of the incompleteness of accessible information and of the physical signification of ω on the basis of fractal phase space. ω is shown to be proportional to the fractal dimension of the phase space and can be linked to the phase volume expansion and information growth during the scale refining process
Nontrivial correlation between the CKM and MNS matrices
International Nuclear Information System (INIS)
Xing Zhizhong
2005-01-01
We point out that the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix V CKM and the Maki-Nakagawa-Sakata (MNS) lepton mixing matrix V MNS can naturally be correlated in a class of seesaw models if the Dirac neutrino mass matrix and the up-type quark mass matrix are symmetric and identical, but the texture of their correlation matrix F ν is rather nontrivial. The bimaximal mixing pattern of F ν is disfavored by current data, and other special forms of F ν may suffer from fine-tuning of the free phase parameters in fitting the so-called quark-lepton complementarity relation. A straightforward calculation of F ν in terms of V CKM and V MNS reveals a striking feature of F ν : its (1,3) element cannot be zero or too small, no matter whether the (1,3) elements of V CKM and V MNS are vanishing or not. We also add some brief comments on possible radiative corrections to V CKM and V MNS
Fractals as objects with nontrivial structures at all scales
International Nuclear Information System (INIS)
Lacan, Francis; Tresser, Charles
2015-01-01
Toward the middle of 2001, the authors started arguing that fractals are important when discussing the operational resilience of information systems and related computer sciences issues such as artificial intelligence. But in order to argue along these lines it turned out to be indispensable to define fractals so as to let one recognize as fractals some sets that are very far from being self similar in the (usual) metric sense. This paper is devoted to define (in a loose sense at least) fractals in ways that allow for instance all the Cantor sets to be fractals and that permit to recognize fractality (the property of being fractal) in the context of the information technology issues that we had tried to comprehend. Starting from the meta-definition of a fractal as an “object with non-trivial structure at all scales” that we had used for long, we ended up taking these words seriously. Accordingly we define fractals in manners that depend both on the structures that the fractals are endowed with and the chosen sets of structure compatible maps, i.e., we approach fractals in a category-dependent manner. We expect that this new approach to fractals will contribute to the understanding of more of the fractals that appear in exact and other sciences than what can be handled presently
Patient information in phase I trials
DEFF Research Database (Denmark)
Gad, Katrine Toubro; Lassen, Ulrik; Mau-Sørensen, Morten
2018-01-01
for systematic reviews and meta‐analyses.” A systematic search was performed in the PubMed, Embase, and PsycInfo databases, supplemented by a search for unpublished literature. Results: We identified 37 studies for inclusion in this review. Patients' decisions to participate in a phase 1 trial were influenced....... Studies performing analyses of the dialog demonstrated that the language of the physicians was incomplete. The relatives' perceptions of such information remain unexplored. Most studies had a comprehensive risk of bias. Conclusions: Patients' decisions regarding participation in phase 1 trials are based...
Nontrivial Periodic Solutions for Nonlinear Second-Order Difference Equations
Directory of Open Access Journals (Sweden)
Tieshan He
2011-01-01
Full Text Available This paper is concerned with the existence of nontrivial periodic solutions and positive periodic solutions to a nonlinear second-order difference equation. Under some conditions concerning the first positive eigenvalue of the linear equation corresponding to the nonlinear second-order equation, we establish the existence results by using the topological degree and fixed point index theories.
Nontrivial ac spin response in the effective Luttinger model
International Nuclear Information System (INIS)
Hu Liangbin; Zhong Jiansong; Hu Kaige
2006-01-01
Based on the three-dimensional effective Luttinger Hamiltonian and the exact Heisenberg equations of motion and within a self-consistent semiclassical approximation, we present a theoretical investigation on the nontrivial ac spin responses due to the intrinsic spin-orbit coupling of holes in p-doped bulk semiconductors. We show that the nontrivial ac spin responses induced by the combined action of an ac external electric field and the intrinsic spin-orbit coupling of holes may lead to the generation of a nonvanishing ac spin Hall current in a p-doped bulk semiconductor, which shares some similarities with the dissipationless dc spin Hall current conceived previously and also exhibits some interesting new features that was not found before
Quantization ambiguity and non-trivial vacuum structure
International Nuclear Information System (INIS)
Rothe, H.J.; Swieca, J.A.
1978-01-01
It is pointed out that there is an ambiguity in quantization of any system whose configuration space has a non-trivial topology characterized by a Chern number. In field theories this ambiguity manifests itself through the existence of theta-sectors. The point of view adopted gives a simple interpretation of the difference between the temporal and Coulomb gauge descriptions of instantons. The general ideas are exemplified in the O(3) non-linear sigma-model in two dimensions [pt
High-order noise filtering in nontrivial quantum logic gates.
Green, Todd; Uys, Hermann; Biercuk, Michael J
2012-07-13
Treating the effects of a time-dependent classical dephasing environment during quantum logic operations poses a theoretical challenge, as the application of noncommuting control operations gives rise to both dephasing and depolarization errors that must be accounted for in order to understand total average error rates. We develop a treatment based on effective Hamiltonian theory that allows us to efficiently model the effect of classical noise on nontrivial single-bit quantum logic operations composed of arbitrary control sequences. We present a general method to calculate the ensemble-averaged entanglement fidelity to arbitrary order in terms of noise filter functions, and provide explicit expressions to fourth order in the noise strength. In the weak noise limit we derive explicit filter functions for a broad class of piecewise-constant control sequences, and use them to study the performance of dynamically corrected gates, yielding good agreement with brute-force numerics.
Future foam: Nontrivial topology from bubble collisions in eternal inflation
International Nuclear Information System (INIS)
Bousso, Raphael; Freivogel, Ben; Yang, I-S.; Sekino, Yasuhiro; Shenker, Stephen; Susskind, Leonard; Yeh, C.-P.
2008-01-01
We study pocket universes which have zero cosmological constant and nontrivial boundary topology. These arise from bubble collisions in eternal inflation. Using a simplified dust model of collisions we find that boundaries of any genus can occur. Using a radiation shell model we perform analytic studies in the thin-wall limit to show the existence of geometries with a single toroidal boundary. We give plausibility arguments that higher genus boundaries can also occur. In geometries with one boundary of any genus a timelike observer can see the entire boundary. Geometries with multiple disconnected boundaries can also occur. In the spherical case with two boundaries the boundaries are separated by a horizon. Our results suggest that the holographic dual description for eternal inflation, proposed by Freivogel, Sekino, Susskind and Yeh, should include summation over the genus of the base space of the dual conformal field theory. We point out peculiarities of this genus expansion compared to the string perturbation series.
Magnetically charged calorons with non-trivial holonomy
Kato, Takumi; Nakamula, Atsushi; Takesue, Koki
2018-06-01
Instantons in pure Yang-Mills theories on partially periodic space R^3× {S}^1 are usually called calorons. The background periodicity brings on characteristic features of calorons such as non-trivial holonomy, which plays an essential role for confinement/deconfinement transition in pure Yang-Mills gauge theory. For the case of gauge group SU(2), calorons can be interpreted as composite objects of two constituent "monopoles" with opposite magnetic charges. There are often the cases that the two monopole charges are unbalanced so that the calorons possess net magnetic charge in R3. In this paper, we consider several mechanism how such net magnetic charges appear for certain types of calorons through the ADHM/Nahm construction with explicit examples. In particular, we construct analytically the gauge configuration of the (2 , 1)-caloron with U(1)-symmetry, which has intrinsically magnetic charge.
Imprints of spherical nontrivial topologies on the cosmic microwave background.
Niarchou, Anastasia; Jaffe, Andrew
2007-08-24
The apparent low power in the cosmic microwave background (CMB) temperature anisotropy power spectrum derived from the Wilkinson Microwave Anisotropy Probe motivated us to consider the possibility of a nontrivial topology. We focus on simple spherical multiconnected manifolds and discuss their implications for the CMB in terms of the power spectrum, maps, and the correlation matrix. We perform a Bayesian model comparison against the fiducial best-fit cold dark matter model with a cosmological constant based both on the power spectrum and the correlation matrix to assess their statistical significance. We find that the first-year power spectrum shows a slight preference for the truncated cube space, but the three-year data show no evidence for any of these spaces.
Dirac fermions in nontrivial topology black hole backgrounds
International Nuclear Information System (INIS)
Gozdz, Marek; Nakonieczny, Lukasz; Rogatko, Marek
2010-01-01
We discuss the behavior of the Dirac fermions in a general spherically symmetric black hole background with a nontrivial topology of the event horizon. Both massive and massless cases are taken into account. We will conduct an analytical study of intermediate and late-time behavior of massive Dirac hair in the background of a black hole with a global monopole and dilaton black hole pierced by a cosmic string. In the case of a global monopole swallowed by a static black hole, the intermediate late-time behavior depends on the mass of the Dirac field, the multiple number of the wave mode, and the global monopole parameter. The late-time behavior is quite independent of these factors and has a decay rate proportional to t -5/6 . As far as the black hole pierced by a cosmic string is concerned, the intermediate late-time behavior depends only on the hair mass and the multipole number of the wave mode, while the late-time behavior dependence is the same as in the previous case. The main modification stems from the topology of the S 2 sphere pierced by a cosmic string. This factor modifies the eigenvalues of the Dirac operator acting on the transverse manifold.
NMR Evidence for the Topologically Nontrivial Nature in a Family of Half-Heusler Compounds
Zhang, Xiaoming
2016-03-16
Spin-orbit coupling (SOC) is expected to partly determine the topologically nontrivial electronic structure of heavy half-Heusler ternary compounds. However, to date, attempts to experimentally observe either the strength of SOC or how it modifies the bulk band structure have been unsuccessful. By using bulk-sensitive nuclear magnetic resonance (NMR) spectroscopy combined with first-principles calculations, we reveal that 209Bi NMR isotropic shifts scale with relativity in terms of the strength of SOC and average atomic numbers, indicating strong relativistic effects on NMR parameters. According to first-principles calculations, we further claim that nuclear magnetic shieldings from relativistic p1/2 states and paramagnetic contributions from low-lying unoccupied p3/2 states are both sensitive to the details of band structures tuned by relativity, which explains why the hidden relativistic effects on band structure can be revealed by 209Bi NMR isotropic shifts in topologically nontrivial half-Heusler compounds. Used in complement to surface-sensitive methods, such as angle resolved photon electron spectroscopy and scanning tunneling spectroscopy, NMR can provide valuable information on bulk electronic states.
NMR Evidence for the Topologically Nontrivial Nature in a Family of Half-Heusler Compounds
Zhang, Xiaoming; Hou, Zhipeng; Wang, Yue; Xu, Guizhou; Shi, Chenglong; Liu, EnKe; Xi, Xuekui; Wang, Wenhong; Wu, Guangheng; Zhang, Xixiang
2016-01-01
Spin-orbit coupling (SOC) is expected to partly determine the topologically nontrivial electronic structure of heavy half-Heusler ternary compounds. However, to date, attempts to experimentally observe either the strength of SOC or how it modifies the bulk band structure have been unsuccessful. By using bulk-sensitive nuclear magnetic resonance (NMR) spectroscopy combined with first-principles calculations, we reveal that 209Bi NMR isotropic shifts scale with relativity in terms of the strength of SOC and average atomic numbers, indicating strong relativistic effects on NMR parameters. According to first-principles calculations, we further claim that nuclear magnetic shieldings from relativistic p1/2 states and paramagnetic contributions from low-lying unoccupied p3/2 states are both sensitive to the details of band structures tuned by relativity, which explains why the hidden relativistic effects on band structure can be revealed by 209Bi NMR isotropic shifts in topologically nontrivial half-Heusler compounds. Used in complement to surface-sensitive methods, such as angle resolved photon electron spectroscopy and scanning tunneling spectroscopy, NMR can provide valuable information on bulk electronic states.
Generalized phase retrieval algorithm based on information measures
Shioya, Hiroyuki; Gohara, Kazutoshi
2006-01-01
An iterative phase retrieval algorithm based on the maximum entropy method (MEM) is presented. Introducing a new generalized information measure, we derive a novel class of algorithms which includes the conventionally used error reduction algorithm and a MEM-type iterative algorithm which is presented for the first time. These different phase retrieval methods are unified on the basis of the framework of information measures used in information theory.
Yang-Lee zeros for a Potts model of helix-coil transition with nontrivial topology
International Nuclear Information System (INIS)
Ananikian, N.; Ananikyan, L.; Artuso, R.; Sargsyan, K.
2007-07-01
The Yang-Lee partition function zeros of the Q-state Potts model on a zigzag ladder are studied by a transfer-matrix approach. This Q-state model has a non-trivial topology induced by three-site interactions on a zigzag ladder and is proposed as a description of helix-coil transition in homo-polymers. The Yang-Lee zeros are associated to complex values of the solvent-related coupling constant K (magnetic field) and they are exactly derived for arbitrary values of the system parameters: Q, J (coupling constant of hydrogen binding) and temperature. It is shown that there is only a quasi-phase transition for all temperatures. The densities of the Yang-Lee zeros are singular at the edge singularity points and the critical exponent σ = -1/2. (author)
Quantum oscillation and nontrivial transport in the Dirac semimetal Cd_3As_2 nanodevice
International Nuclear Information System (INIS)
Pan, Haiyang; Wei, Zhongxia; Zhao, Bo; Song, Fengqi; Wang, Baigeng; Zhang, Kang; Gao, Ming; Wang, Xuefeng; Zhang, Rong; Wang, Jue; Han, Min; Pi, Li
2016-01-01
Here, we report on the Shubnikov-de Haas oscillation in high-quality Cd_3As_2 nanowires grown by a chemical vapor deposition approach. The dominant transport of topological Dirac fermions is evident by the nontrivial Berry phase in the Landau Fan diagram. The quantum oscillations rise at a small field of 2 T and preserves up to 100 K, revealing a sizeable Landau level gap and a device mobility of 2138 cm"2" V"−"1" s"−"1. The angle-variable oscillations indicate the isotropy of the bulk Dirac transport. The large estimated mean free path makes the Cd_3As_2 nanowire a promising platform for the one-dimensional transport of Dirac semimetals.
International Nuclear Information System (INIS)
Chaichian, M.; Tureanu, A.; Demichev, A.; Presnajder, P.; Sheikh-Jabbari, M.M.
2001-02-01
After discussing the peculiarities of quantum systems on noncommutative (NC) spaces with nontrivial topology and the operator representation of the *-product on them, we consider the Aharonov-Bohm and Casimir effects for such spaces. For the case of the Aharonov-Bohm effect, we have obtained an explicit expression for the shift of the phase, which is gauge invariant in the NC sense. The Casimir energy of a field theory on a NC cylinder is divergent, while it becomes finite on a torus, when the dimensionless parameter of noncommutativity is a rational number. The latter corresponds to a well-defined physical picture. Certain distinctions from other treatments based on a different way of taking the noncommutativity into account are also discussed. (author)
Multiple-stage pure phase encoding with biometric information
Chen, Wen
2018-01-01
In recent years, many optical systems have been developed for securing information, and optical encryption/encoding has attracted more and more attention due to the marked advantages, such as parallel processing and multiple-dimensional characteristics. In this paper, an optical security method is presented based on pure phase encoding with biometric information. Biometric information (such as fingerprint) is employed as security keys rather than plaintext used in conventional optical security systems, and multiple-stage phase-encoding-based optical systems are designed for generating several phase-only masks with biometric information. Subsequently, the extracted phase-only masks are further used in an optical setup for encoding an input image (i.e., plaintext). Numerical simulations are conducted to illustrate the validity, and the results demonstrate that high flexibility and high security can be achieved.
Self-ordering of nontrivial topological polarization structures in nanoporous ferroelectrics.
Van Lich, Le; Shimada, Takahiro; Wang, Jie; Kitamura, Takayuki
2017-10-19
Topological field structures, such as skyrmions, merons, and vortices, are important features found in ordered systems with spontaneously broken symmetry. A plethora of topological field structures have been discovered in magnetic and ordered soft matter systems due to the presence of inherent chiral interactions, and this has provided a fruitful platform for unearthing additional groundbreaking functionalities. However, despite being one of the most important classes of ordered systems, ferroelectrics scarcely form topological polarization structures due to their lack of intrinsic chiral interactions. In the present study, we demonstrate using multiphysics phase-field modelling based on the Ginzburg-Landau theory that a rich assortment of nontrivial topological polarization structures, including hedgehogs, antivortices, multidirectional vortices, and vortex arrays, can be spontaneously formed in three-dimensional nanoporous ferroelectric structures. We realize that confining ferroelectrics to trivial geometries that are incompatible with the orientation symmetry may impose extrinsic frustration to the polarization field through the enhancement of depolarization fields at free porous surfaces. This frustration gives rise to symmetry breaking, resulting in the formation of nontrivial topological polarization structures as the ground state. We further topologically characterize the local accommodation of polarization structures by viewing them in a new perspective, in which polarization ordering can be mapped on the order parameter space, according to the topological theory of defects and homotopy theory. The results indicate that the nanoporous structures contain composite topological objects composed of two or more elementary topological polarization structures. The present study therefore offers a playground for exploring novel physical phenomena in ferroelectric systems as well as a novel nanoelectronics characterization platform for future topology
Phase space view of quantum mechanical systems and Fisher information
International Nuclear Information System (INIS)
Nagy, Á.
2016-01-01
Highlights: • Phase-space Fisher information coming from the canonical distribution is derived for the ground state of quantum mechanical systems. • Quantum mechanical phase-space Fisher information contains an extra term due to the position dependence of the temperature. • A complete analogy to the classical case is demonstrated for the linear harmonic oscillator. - Abstract: Pennini and Plastino showed that the form of the Fisher information generated by the canonical distribution function reflects the intrinsic structure of classical mechanics. Now, a quantum mechanical generalization of the Pennini–Plastino theory is presented based on the thermodynamical transcription of the density functional theory. Comparing to the classical case, the phase-space Fisher information contains an extra term due to the position dependence of the temperature. However, for the special case of constant temperature, the expression derived bears resemblance to the classical one. A complete analogy to the classical case is demonstrated for the linear harmonic oscillator.
Phase space view of quantum mechanical systems and Fisher information
Energy Technology Data Exchange (ETDEWEB)
Nagy, Á., E-mail: anagy@madget.atomki.hu
2016-06-17
Highlights: • Phase-space Fisher information coming from the canonical distribution is derived for the ground state of quantum mechanical systems. • Quantum mechanical phase-space Fisher information contains an extra term due to the position dependence of the temperature. • A complete analogy to the classical case is demonstrated for the linear harmonic oscillator. - Abstract: Pennini and Plastino showed that the form of the Fisher information generated by the canonical distribution function reflects the intrinsic structure of classical mechanics. Now, a quantum mechanical generalization of the Pennini–Plastino theory is presented based on the thermodynamical transcription of the density functional theory. Comparing to the classical case, the phase-space Fisher information contains an extra term due to the position dependence of the temperature. However, for the special case of constant temperature, the expression derived bears resemblance to the classical one. A complete analogy to the classical case is demonstrated for the linear harmonic oscillator.
Topologically nontrivial black holes in Lovelock-Born-Infeld gravity
Farhangkhah, N.
2018-04-01
We present the black hole solutions possessing horizon with nonconstant-curvature and additional scalar restrictions on the base manifold in Lovelock gravity coupled to Born-Infeld (BI) nonlinear electrodynamics. The asymptotic and near origin behavior of the metric is presented and we analyze different behaviors of the singularity. We find that, in contrast to the case of black hole solutions of BI-Lovelock gravity with constant curvature horizon and Maxwell-Lovelock gravity with non constant horizon which have only timelike singularities, spacelike, and timelike singularities may exist for BI-Lovelock black holes with nonconstant curvature horizon. By calculating the thermodynamic quantities, we study the effects of nonlinear electrodynamics via the Born-Infeld action. Stability analysis shows that black holes with positive sectional curvature, κ , possess an intermediate unstable phase and large and small black holes are stable. We see that while Ricci flat Lovelock-Born-Infeld black holes having exotic horizons are stable in the presence of Maxwell field or either Born Infeld field with large born Infeld parameter β , unstable phase appears for smaller values of β , and therefore nonlinearity brings in the instability.
Directory of Open Access Journals (Sweden)
Guanwei Chen
2014-01-01
Full Text Available We study the existence of positive solutions and multiplicity of nontrivial solutions for a class of quasilinear elliptic equations by using variational methods. Our obtained results extend some existing ones.
Nontrivial Solution of Fractional Differential System Involving Riemann-Stieltjes Integral Condition
Directory of Open Access Journals (Sweden)
Ge-Feng Yang
2012-01-01
differential system involving the Riemann-Stieltjes integral condition, by using the Leray-Schauder nonlinear alternative and the Banach contraction mapping principle, some sufficient conditions of the existence and uniqueness of a nontrivial solution of a system are obtained.
Decoding English Alphabet Letters Using EEG Phase Information
Directory of Open Access Journals (Sweden)
YiYan Wang
2018-02-01
Full Text Available Increasing evidence indicates that the phase pattern and power of the low frequency oscillations of brain electroencephalograms (EEG contain significant information during the human cognition of sensory signals such as auditory and visual stimuli. Here, we investigate whether and how the letters of the alphabet can be directly decoded from EEG phase and power data. In addition, we investigate how different band oscillations contribute to the classification and determine the critical time periods. An English letter recognition task was assigned, and statistical analyses were conducted to decode the EEG signal corresponding to each letter visualized on a computer screen. We applied support vector machine (SVM with gradient descent method to learn the potential features for classification. It was observed that the EEG phase signals have a higher decoding accuracy than the oscillation power information. Low-frequency theta and alpha oscillations have phase information with higher accuracy than do other bands. The decoding performance was best when the analysis period began from 180 to 380 ms after stimulus presentation, especially in the lateral occipital and posterior temporal scalp regions (PO7 and PO8. These results may provide a new approach for brain-computer interface techniques (BCI and may deepen our understanding of EEG oscillations in cognition.
Partial information, market efficiency, and anomalous continuous phase transition
International Nuclear Information System (INIS)
Yang, Guang; Zheng, Wenzhi; Huang, Jiping
2014-01-01
It is a common belief in economics and social science that if there is more information available for agents to gather in a human system, the system can become more efficient. The belief can be easily understood according to the well-known efficient market hypothesis. In this work, we attempt to challenge this belief by investigating a complex adaptive system, which is modeled by a market-directed resource-allocation game with a directed random network. We conduct a series of controlled human experiments in the laboratory to show the reliability of the model design. As a result, we find that even under a small information concentration, the system can still almost reach the optimal (balanced) state. Furthermore, the ensemble average of the system’s fluctuation level goes through a continuous phase transition. This behavior means that in the second phase if too much information is shared among agents, the system’s stability will be harmed instead, which differs from the belief mentioned above. Also, at the transition point, the ensemble fluctuations of the fluctuation level remain at a low value. This phenomenon is in contrast to the textbook knowledge about continuous phase transitions in traditional physical systems, namely, fluctuations will rise abnormally around a transition point since the correlation length becomes infinite. Thus, this work is of potential value to a variety of fields, such as physics, economics, complexity science, and artificial intelligence. (paper)
Partial information, market efficiency, and anomalous continuous phase transition
Yang, Guang; Zheng, Wenzhi; Huang, Jiping
2014-04-01
It is a common belief in economics and social science that if there is more information available for agents to gather in a human system, the system can become more efficient. The belief can be easily understood according to the well-known efficient market hypothesis. In this work, we attempt to challenge this belief by investigating a complex adaptive system, which is modeled by a market-directed resource-allocation game with a directed random network. We conduct a series of controlled human experiments in the laboratory to show the reliability of the model design. As a result, we find that even under a small information concentration, the system can still almost reach the optimal (balanced) state. Furthermore, the ensemble average of the system’s fluctuation level goes through a continuous phase transition. This behavior means that in the second phase if too much information is shared among agents, the system’s stability will be harmed instead, which differs from the belief mentioned above. Also, at the transition point, the ensemble fluctuations of the fluctuation level remain at a low value. This phenomenon is in contrast to the textbook knowledge about continuous phase transitions in traditional physical systems, namely, fluctuations will rise abnormally around a transition point since the correlation length becomes infinite. Thus, this work is of potential value to a variety of fields, such as physics, economics, complexity science, and artificial intelligence.
Phase transition and information cascade in a voting model
Energy Technology Data Exchange (ETDEWEB)
Hisakado, M [Standard and Poor' s, Marunouchi 1-6-5, Chiyoda ku, Tokyo 100-0005 (Japan); Mori, S, E-mail: masato_hisakado@standardandpoors.co, E-mail: mori@sci.kitasato-u.ac.j [Department of Physics, School of Science, Kitasato University, Kitasato 1-15-1, Sagamihara, Kanagawa 228-8555 (Japan)
2010-08-06
In this paper, we introduce a voting model that is similar to a Keynesian beauty contest and analyse it from a mathematical point of view. There are two types of voters-copycat and independent-and two candidates. Our voting model is a binomial distribution (independent voters) doped in a beta binomial distribution (copycat voters). We find that the phase transition in this system is at the upper limit of t, where t is the time (or the number of the votes). Our model contains three phases. If copycats constitute a majority or even half of the total voters, the voting rate converges more slowly than it would in a binomial distribution. If independents constitute the majority of voters, the voting rate converges at the same rate as it would in a binomial distribution. We also study why it is difficult to estimate the conclusion of a Keynesian beauty contest when there is an information cascade.
Phase transition and information cascade in a voting model
International Nuclear Information System (INIS)
Hisakado, M; Mori, S
2010-01-01
In this paper, we introduce a voting model that is similar to a Keynesian beauty contest and analyse it from a mathematical point of view. There are two types of voters-copycat and independent-and two candidates. Our voting model is a binomial distribution (independent voters) doped in a beta binomial distribution (copycat voters). We find that the phase transition in this system is at the upper limit of t, where t is the time (or the number of the votes). Our model contains three phases. If copycats constitute a majority or even half of the total voters, the voting rate converges more slowly than it would in a binomial distribution. If independents constitute the majority of voters, the voting rate converges at the same rate as it would in a binomial distribution. We also study why it is difficult to estimate the conclusion of a Keynesian beauty contest when there is an information cascade.
Phase transition and information cascade in a voting model
Hisakado, M.; Mori, S.
2010-08-01
In this paper, we introduce a voting model that is similar to a Keynesian beauty contest and analyse it from a mathematical point of view. There are two types of voters—copycat and independent—and two candidates. Our voting model is a binomial distribution (independent voters) doped in a beta binomial distribution (copycat voters). We find that the phase transition in this system is at the upper limit of t, where t is the time (or the number of the votes). Our model contains three phases. If copycats constitute a majority or even half of the total voters, the voting rate converges more slowly than it would in a binomial distribution. If independents constitute the majority of voters, the voting rate converges at the same rate as it would in a binomial distribution. We also study why it is difficult to estimate the conclusion of a Keynesian beauty contest when there is an information cascade.
Exploring topological phases with quantum walks
International Nuclear Information System (INIS)
Kitagawa, Takuya; Rudner, Mark S.; Berg, Erez; Demler, Eugene
2010-01-01
The quantum walk was originally proposed as a quantum-mechanical analog of the classical random walk, and has since become a powerful tool in quantum information science. In this paper, we show that discrete-time quantum walks provide a versatile platform for studying topological phases, which are currently the subject of intense theoretical and experimental investigations. In particular, we demonstrate that recent experimental realizations of quantum walks with cold atoms, photons, and ions simulate a nontrivial one-dimensional topological phase. With simple modifications, the quantum walk can be engineered to realize all of the topological phases, which have been classified in one and two dimensions. We further discuss the existence of robust edge modes at phase boundaries, which provide experimental signatures for the nontrivial topological character of the system.
Generalized hedgehog ansatz and Gribov copies in regions with nontrivial topologies
Canfora, Fabrizio; Salgado-Rebolledo, Patricio
2013-02-01
In this paper the arising of Gribov copies both in Landau and Coulomb gauges in regions with nontrivial topologies but flat metric, (such as closed tubes S1×D2, or R×T2) will be analyzed. Using a novel generalization of the hedgehog ansatz beyond spherical symmetry, analytic examples of Gribov copies of the vacuum will be constructed. Using such ansatz, we will also construct the elliptic Gribov pendulum. The requirement of absence of Gribov copies of the vacuum satisfying the strong boundary conditions implies geometrical constraints on the shapes and sizes of the regions with nontrivial topologies.
Information about robustness, reliability and safety in early design phases
DEFF Research Database (Denmark)
Marini, Vinicius Kaster
methods, and an industrial case to assess how the use of information about robustness, reliability and safety as practised by current methods influences concept development. Current methods cannot be used in early design phases due to their dependence on detailed design information for the identification...... alternatives. This prompts designers to reuse working principles that are inherently flawed, as they are liable to disturbances, failures and hazards. To address this issue, an approach based upon individual records of early design issues consists of comparing failures and benefits from prior working...... principles, before making a decision, and improving the more suitable alternatives through this feedback. Workshops were conducted with design practitioners to evaluate the potential of the approach and to simulate decision-making and gain feedback on a proof-of-concept basis. The evaluation has demonstrated...
Informing Early-Phase Technology Decisions in Paradigmatic Innovation
DEFF Research Database (Denmark)
Jensen, Ole Kjeldal; Ahmed-Kristensen, Saeema
2010-01-01
their knowledge-world in such a radical manner, they start facing problems with making efficient decisions as knowledge generated through experience is mainly useful when the future mimics the past, which is not the case for such radical changes. Therefore, a 3 year long research project within this industry has......The innovation activities of a company facing paradigmatic change with regard to both technology and business model includes taking many decisions, where the information available, as well as the decision makers’ ability to understand this information, is limited. Technology decisions in the very...... early phases of innovation have been explored in a Scandinavian energy-utilities company facing exactly these paradigmatic changes. In the company there are 5500 employees, with the major footprint in Denmark. The company has activities in the full energy value-chain including: production & trade of oil...
Tomamichel, M; Sessa, C; Herzig, S; de Jong, J; Pagani, O; Willems, Y; Cavalli, F
1995-04-01
The process by which patients are informed and their consent is obtained in phase I trials has thus far been only marginally studied. Since 1986 we have followed an oral procedure, consisting of three consecutive conversations in which the investigator responsible for phase I studies, the research nurse and the patients' relatives and/or friends also participate, followed by the patients signing of a written consent form. It is required that six items of information considered essential by our staff be conveyed to patients by the responsible investigator. Meerwein's model, which defines three main dimensions of the informing process (the information itself, the emotional and interactive aspects), has been studied to ascertain whether it can be applied to evaluate the quality of the information proffered. Thirty-two conversations were taped, transcribed and evaluated by one psychiatrist and one psychologist. A quantitative analysis of information was performed by calculating the number of patients to whom the essential items of information had been conveyed. The qualitative analysis was performed by rating on a five-point scoring system, from 1 (very bad) to 5 (excellent), the three dimensions of the informing process for each patient and by calculating for each dimension the mean score of the constituent items. Complete information about the characteristics of the phase I drug and the modalities of the treatment and follow up was given to almost 80% of the patients. All but one of the items of the information dimension scored 3.5 or higher, with the one related to the assessment by the doctor of the patient's understanding at the end of the consultation scoring less than 3 in 53% of the patients. All items of the emotional dimension scored higher than 3.5. Greater difficulty was encountered by the physician with the interactive dimension, the lowest mean scores being reported on the items related to the doctor's awareness of the indirectly expressed anxieties of
International Nuclear Information System (INIS)
Ge Fengjun; Jiang Shaozhou; Wang Qing
2011-01-01
The electroweak chiral Lagrangian for the topcolor-assisted technicolor model proposed by K. Lane, which uses nontrivial patterns of techniquark condensation and walking, was investigated in this study. We found that the features of the model are qualitatively similar to those of Lane's previous natural topcolor-assisted technicolor prototype model, but there is no limit on the upper bound of the Z ' mass. We discuss the phase structure and possible walking behavior of the model. We obtained the values of all coefficients of the electroweak chiral Lagrangian up to an order of p 4 . We show that although the walking effect reduces the S parameter to half its original value, it maintains an order of 2. Moreover, a special hypercharge arrangement is needed to achieve further reductions in its value.
International Nuclear Information System (INIS)
Kimura, Masashi
2008-01-01
We show that there exist five-dimensional multi-black hole solutions which have analytic event horizons when the space-time has nontrivial asymptotic structure, unlike the case of five-dimensional multi-black hole solutions in asymptotically flat space-time.
Geometric structure and information change in phase transitions
Kim, Eun-jin; Hollerbach, Rainer
2017-06-01
We propose a toy model for a cyclic order-disorder transition and introduce a geometric methodology to understand stochastic processes involved in transitions. Specifically, our model consists of a pair of forward and backward processes (FPs and BPs) for the emergence and disappearance of a structure in a stochastic environment. We calculate time-dependent probability density functions (PDFs) and the information length L , which is the total number of different states that a system undergoes during the transition. Time-dependent PDFs during transient relaxation exhibit strikingly different behavior in FPs and BPs. In particular, FPs driven by instability undergo the broadening of the PDF with a large increase in fluctuations before the transition to the ordered state accompanied by narrowing the PDF width. During this stage, we identify an interesting geodesic solution accompanied by the self-regulation between the growth and nonlinear damping where the time scale τ of information change is constant in time, independent of the strength of the stochastic noise. In comparison, BPs are mainly driven by the macroscopic motion due to the movement of the PDF peak. The total information length L between initial and final states is much larger in BPs than in FPs, increasing linearly with the deviation γ of a control parameter from the critical state in BPs while increasing logarithmically with γ in FPs. L scales as |lnD | and D-1 /2 in FPs and BPs, respectively, where D measures the strength of the stochastic forcing. These differing scalings with γ and D suggest a great utility of L in capturing different underlying processes, specifically, diffusion vs advection in phase transition by geometry. We discuss physical origins of these scalings and comment on implications of our results for bistable systems undergoing repeated order-disorder transitions (e.g., fitness).
Effects of phase lag on the information rate of a bistable Duffing oscillator
Energy Technology Data Exchange (ETDEWEB)
Perkins, Edmon, E-mail: edmon@umd.edu; Balachandran, Balakumar, E-mail: balab@umd.edu
2015-02-06
To utilize noise for systems, which are transmitting or receiving information, the information rate is a necessary metric to consider. The phase lag, which is the difference between the sender (applied forcing) and receiver (the oscillator) phases, has a significant effect on the information rate. However, this phase lag is a nonlinear function of the noise level. Here, the effects of phase lag on the information rate for a Duffing oscillator are examined and comparative discussions are made with phase lag from linear response theory. The phase lag is shown to be an important variable in calculating the information rate. - Highlights: • Simulations and Fokker–Planck analysis for Duffing oscillator response are performed. • The phase lag is found to be a nonlinear function of the noise level. • The phase lag is shown to be important for calculating the information rate metric.
Effects of phase lag on the information rate of a bistable Duffing oscillator
International Nuclear Information System (INIS)
Perkins, Edmon; Balachandran, Balakumar
2015-01-01
To utilize noise for systems, which are transmitting or receiving information, the information rate is a necessary metric to consider. The phase lag, which is the difference between the sender (applied forcing) and receiver (the oscillator) phases, has a significant effect on the information rate. However, this phase lag is a nonlinear function of the noise level. Here, the effects of phase lag on the information rate for a Duffing oscillator are examined and comparative discussions are made with phase lag from linear response theory. The phase lag is shown to be an important variable in calculating the information rate. - Highlights: • Simulations and Fokker–Planck analysis for Duffing oscillator response are performed. • The phase lag is found to be a nonlinear function of the noise level. • The phase lag is shown to be important for calculating the information rate metric
Nontrivial effects of high-frequency excitation for strongly damped mechanical systems
DEFF Research Database (Denmark)
Fidlin, Alexander; Thomsen, Jon Juel
2008-01-01
Some non-trivial effects are investigated, which can occur if strongly damped mechanical systems are subjected to strong high-frequency (HF) excitation. The main result is a theoretical prediction, supported by numerical simulation, that for such systems the (quasi-)equilibrium states can change...... that can be substantial depending on the strength of the HF excitation) for finite values of the damping. The analysis is focused on the differences between the classic results for weakly damped systems, and new effects for which the strong damping terms are responsible. The analysis is based on a slightly...... modified averaging technique, and includes an elementary example of an elliptically excited pendulum for illustration, alongside with a generalization to a broader class of strongly damped dynamical systems with HF excitation. As an application example, the nontrivial behavior of a classical optimally...
Nontrivial effects of high-frequency excitation for strongly damped mechanical systems
DEFF Research Database (Denmark)
Fidlin, Alexander; Thomsen, Jon Juel
Some nontrivial effects are investigated, which can occur if strongly damped mechanical systems are subjected to strong high-frequency (HF) excitation. The main result is a theoretical prediction, supported by numerical simulation, that for such systems the (quasi-)equilibrium states can change...... that can be substantial (depending on the strength of the HF excitation) for finite values of the damping. The analysis is focused on the differences between the classic results for weakly damped systems, and new effects for which the strong damping terms are responsible. The analysis is based...... on a slightly modified averaging technique, and includes an elementary example of an elliptically excited pendulum for illustration, alongside with a generalization to a broader class of strongly damped dynamical systems with HF excitation. As an application example, the nontrivial behavior of a classical...
Spin model for nontrivial types of magnetic order in inverse-perovskite antiferromagnets
Mochizuki, Masahito; Kobayashi, Masaya; Okabe, Reoya; Yamamoto, Daisuke
2018-02-01
Nontrivial magnetic orders in the inverse-perovskite manganese nitrides are theoretically studied by constructing a classical spin model describing the magnetic anisotropy and frustrated exchange interactions inherent in specific crystal and electronic structures of these materials. With a replica-exchange Monte Carlo technique, a theoretical analysis of this model reproduces the experimentally observed triangular Γ5 g and Γ4 g spin-ordered patterns and the systematic evolution of magnetic orders. Our Rapid Communication solves a 40-year-old problem of nontrivial magnetism for the inverse-perovskite manganese nitrides and provides a firm basis for clarifying the magnetism-driven negative thermal expansion phenomenon discovered in this class of materials.
Programming Non-Trivial Algorithms in the Measurement Based Quantum Computation Model
Energy Technology Data Exchange (ETDEWEB)
Alsing, Paul [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Fanto, Michael [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Lott, Capt. Gordon [United States Air Force Research Laboratory, Wright-Patterson Air Force Base; Tison, Christoper C. [United States Air Force Research Laboratory, Wright-Patterson Air Force Base
2014-01-01
We provide a set of prescriptions for implementing a quantum circuit model algorithm as measurement based quantum computing (MBQC) algorithm1, 2 via a large cluster state. As means of illustration we draw upon our numerical modeling experience to describe a large graph state capable of searching a logical 8 element list (a non-trivial version of Grover's algorithm3 with feedforward). We develop several prescriptions based on analytic evaluation of cluster states and graph state equations which can be generalized into any circuit model operations. Such a resulting cluster state will be able to carry out the desired operation with appropriate measurements and feed forward error correction. We also discuss the physical implementation and the analysis of the principal 3-qubit entangling gate (Toffoli) required for a non-trivial feedforward realization of an 8-element Grover search algorithm.
Additional phase information from UV damage of selenomethionine labelled proteins
Energy Technology Data Exchange (ETDEWEB)
Sanctis, Daniele de [ESRF, Structural Biology Group, 6 rue Jules Horowitz, 38043 Grenoble Cedex (France); Tucker, Paul A.; Panjikar, Santosh, E-mail: panjikar@embl-hamburg.de [EMBL Hamburg Outstation, c/o DESY, Notkestrasse 85, D-22603 Hamburg (Germany)
2011-05-01
Successful examples of ultraviolet radiation-damage-induced phasing with anomalous scattering from selenomethionine protein crystals have been demonstrated. Currently, selenium is the most widely used phasing vehicle for experimental phasing, either by single anomalous scattering or multiple-wavelength anomalous dispersion (MAD) procedures. The use of the single isomorphous replacement anomalous scattering (SIRAS) phasing procedure with selenomethionine containing proteins is not so commonly used, as it requires isomorphous native data. Here it is demonstrated that isomorphous differences can be measured from intensity changes measured from a selenium labelled protein crystal before and after UV exposure. These can be coupled with the anomalous signal from the dataset collected at the selenium absorption edge to obtain SIRAS phases in a UV-RIPAS phasing experiment. The phasing procedure for two selenomethionine proteins, the feruloyl esterase module of xylanase 10B from Clostridium thermocellum and the Mycobacterium tuberculosis chorismate synthase, have been investigated using datasets collected near the absorption edge of selenium before and after UV radiation. The utility of UV radiation in measuring radiation damage data for isomorphous differences is highlighted and it is shown that, after such measurements, the UV-RIPAS procedure yields comparable phase sets with those obtained from the conventional MAD procedure. The results presented are encouraging for the development of alternative phasing approaches for selenomethionine proteins in difficult cases.
2010-04-01
... 25 Indians 2 2010-04-01 2010-04-01 false Is it mandatory to go through the information phase before initiating the negotiation phase? 1000.168 Section 1000.168 Indians OFFICE OF THE ASSISTANT SECRETARY, INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ANNUAL FUNDING AGREEMENTS UNDER THE TRIBAL SELF-GOVERNMENT ACT AMENDMENTS TO THE INDIAN...
NON-TRIVIALITY OF THE RESULTS OF MILGRAM FIELD EXPERIMENT IN MOSCOW AND NEW YORK SUBWAY
Directory of Open Access Journals (Sweden)
Olga V Mitina
2017-12-01
Full Text Available Non-triviality of the results of the field experiment conducted on Stanley Milgram’s methodology in the New York and Moscow subway have been studied. The statistical significance of the difference between empirical and predicted results has been taken as the non-triviality criterion. 208 respondents (psychologists and students studying psychology were asked to predict an experimental result in dependence on an experimenter’s and subject’s gender, a subject’s age, and a city where the experiment was carried out. The obtained results have confirmed our hypothesis on non-triviality of the experiments in subways: it has been showed that there is a statistically significant difference between real behavior of subway passengers (in New York and in Moscow and predictions made by Moscow and Tashkent respondents. Practically in most cases the predicted probability that a subject gives a seat after request of experimenter (young woman or young man is much less than in reality. The structural equation modeling (SEM has been used to analyze the data by constructing the model taking account of all factors mentioned above. The model fit the experimental data well (CFI = 0.919. It has been found that predicted results depend not only on gender, age, and residence of a respondent but also on the degree of familiarity with the research. The obtained data give an important material for a further study of the role of situational (an experiment design and individual (respondent characteristics factors in predicted results; they contribute to further understanding of the problem of creation and support of non-formal social norms in various cultures and show new aspects of research carried out on experimental methodology of Stanley Milgram.
Uganda Health Information Network (UHIN) - Phase IV | IDRC ...
International Development Research Centre (IDRC) Digital Library (Canada)
... reports on drug supplies and use, and continuing education materials. This phase aims to fully integrate the Network into the Ministry of Health district and national ... IWRA/IDRC webinar on climate change and adaptive water management.
International Nuclear Information System (INIS)
Zhou, Changsong; Kurths, Juergen; Hu, Bambi
2001-01-01
We demonstrate the effect of coherence resonance in a heterogeneous array of coupled Fitz Hugh--Nagumo neurons. It is shown that coupling of such elements leads to a significantly stronger coherence compared to that of a single element. We report nontrivial effects of parameter heterogeneity and spatial independence of noise on array-enhanced coherence resonance; especially, we find that (i) the coherence increases as spatial correlation of the noise decreases, and (ii) inhomogeneity in the parameters of the array enhances the coherence. Our results have the implication that generic heterogeneity and background noise can play a constructive role to enhance the time precision of firing in neural systems
Replication of Non-Trivial Directional Motion in Multi-Scales Observed by the Runs Test
Yura, Yoshihiro; Ohnishi, Takaaki; Yamada, Kenta; Takayasu, Hideki; Takayasu, Misako
Non-trivial autocorrelation in up-down statistics in financial market price fluctuation is revealed by a multi-scale runs test(Wald-Wolfowitz test). We apply two models, a stochastic price model and dealer model to understand this property. In both approaches we successfully reproduce the non-stationary directional price motions consistent with the runs test by tuning parameters in the models. We find that two types of dealers exist in the markets, a short-time-scale trend-follower and an extended-time-scale contrarian who are active in different time periods.
Grand unified theory precursors and nontrivial fixed points in higher-dimensional gauge theories
International Nuclear Information System (INIS)
Dienes, Keith R.; Dudas, Emilian; Gherghetta, Tony
2003-01-01
Within the context of traditional logarithmic grand unification at M GUT ≅10 16 GeV, we show that it is nevertheless possible to observe certain GUT states such as X and Y gauge bosons at lower scales, perhaps even in the TeV range. We refer to such states as 'GUT precursors'. These states offer an interesting alternative possibility for new physics at the TeV scale, and could be used to directly probe GUT physics even though the scale of gauge coupling unification remains high. Our results also give rise to a Kaluza-Klein realization of nontrivial fixed points in higher-dimensional gauge theories
Radiative seesaw-type mechanism of fermion masses and non-trivial quark mixing
Energy Technology Data Exchange (ETDEWEB)
Arbelaez, Carolina; Hernandez, A.E.C.; Kovalenko, Sergey; Schmidt, Ivan [Universidad Tecnica Federico Santa Maria, Centro Cientifico-Tecnologico de Valparaiso-CCTVal, Valparaiso (Chile)
2017-06-15
We propose a predictive inert two-Higgs doublet model, where the standard model (SM) symmetry is extended by S{sub 3} x Z{sub 2} x Z{sub 12} and the field content is enlarged by extra scalar fields, charged exotic fermions and two heavy right-handed Majorana neutrinos. The charged exotic fermions generate a non-trivial quark mixing and provide one-loop-level masses for the first- and second-generation charged fermions. The masses of the light active neutrinos are generated from a one-loop-level radiative seesaw mechanism. Our model successfully explains the observed SM fermion mass and mixing pattern. (orig.)
Computing a Non-trivial Lower Bound on the Joint Entropy between Two Images
Energy Technology Data Exchange (ETDEWEB)
Perumalla, Kalyan S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
2017-03-01
In this report, a non-trivial lower bound on the joint entropy of two non-identical images is developed, which is greater than the individual entropies of the images. The lower bound is the least joint entropy possible among all pairs of images that have the same histograms as those of the given images. New algorithms are presented to compute the joint entropy lower bound with a computation time proportional to S log S where S is the number of histogram bins of the images. This is faster than the traditional methods of computing the exact joint entropy with a computation time that is quadratic in S .
Manipulation resolves non-trivial structure of corrole monolayer on Ag(111)
International Nuclear Information System (INIS)
Tebi, Stefano; Serrano, Giulia; Koch, Reinhold; Müllegger, Stefan; Aldahhak, Hazem; Rauls, Eva; Schmidt, Wolf Gero; Schöfberger, Wolfgang
2016-01-01
Non-trivial arrangement of molecules within a molecular network complicates structure determination due to interdigitation, partial overlap, or stacking. We demonstrate that combined imaging and lateral manipulation with a scanning tunneling microscope resolves the intricate structure of a molecular network in two-dimensions in a straightforward manner. The network, formed by a monolayer of 5,10,15-tris(pentafluorophenyl)-corrole molecules on Ag(111), is manipulated for the first time with single-molecule precision. Our results reveal a shingle-like packing of partially overlapping corrole molecules. Density functional theory calculations support our findings. (paper)
Tomographic image reconstruction using x-ray phase information
Momose, Atsushi; Takeda, Tohoru; Itai, Yuji; Hirano, Keiichi
1996-04-01
We have been developing phase-contrast x-ray computed tomography (CT) to make possible the observation of biological soft tissues without contrast enhancement. Phase-contrast x-ray CT requires for its input data the x-ray phase-shift distributions or phase-mapping images caused by an object. These were measured with newly developed fringe-scanning x-ray interferometry. Phase-mapping images at different projection directions were obtained by rotating the object in an x-ray interferometer, and were processed with a standard CT algorithm. A phase-contrast x-ray CT image of a nonstained cancerous tissue was obtained using 17.7 keV synchrotron x rays with 12 micrometer voxel size, although the size of the observation area was at most 5 mm. The cancerous lesions were readily distinguishable from normal tissues. Moreover, fine structures corresponding to cancerous degeneration and fibrous tissues were clearly depicted. It is estimated that the present system is sensitive down to a density deviation of 4 mg/cm3.
Nontrivial paths and periodic orbits of the T-fractal billiard table
Lapidus, Michel L.; Miller, Robyn L.; Niemeyer, Robert G.
2016-07-01
We introduce and prove numerous new results about the orbits of the T-fractal billiard. Specifically, in section 3, we give a variety of sufficient conditions for the existence of a sequence of compatible periodic orbits. In section 4, we examine the limiting behavior of particular sequences of compatible periodic orbits. Additionally, sufficient conditions for the existence of particular nontrivial paths are given in section 4. The proofs of two results of Lapidus and Niemeyer (2013 The current state of fractal billiards Fractal Geometry and Dynamical Systems in Pure and Applied Mathematics II: Fractals in Applied Mathematics (Contemporary Mathematics vol 601) ed D Carfi et al (Providence, RI: American Mathematical Society) pp 251-88 (e-print: arXiv:math.DS.1210.0282v2, 2013) appear here for the first time, as well. In section 5, an orbit with an irrational initial direction reaches an elusive point in a way that yields a nontrivial path of finite length, yet, by our convention, constitutes a singular orbit of the fractal billiard table. The existence of such an orbit seems to indicate that the classification of orbits may not be so straightforward. A discussion of our results and directions for future research is then given in section 6.
Directory of Open Access Journals (Sweden)
E. Kalesaki
2014-01-01
Full Text Available We study theoretically two-dimensional single-crystalline sheets of semiconductors that form a honeycomb lattice with a period below 10 nm. These systems could combine the usual semiconductor properties with Dirac bands. Using atomistic tight-binding calculations, we show that both the atomic lattice and the overall geometry influence the band structure, revealing materials with unusual electronic properties. In rocksalt Pb chalcogenides, the expected Dirac-type features are clouded by a complex band structure. However, in the case of zinc-blende Cd-chalcogenide semiconductors, the honeycomb nanogeometry leads to rich band structures, including, in the conduction band, Dirac cones at two distinct energies and nontrivial flat bands and, in the valence band, topological edge states. These edge states are present in several electronic gaps opened in the valence band by the spin-orbit coupling and the quantum confinement in the honeycomb geometry. The lowest Dirac conduction band has S-orbital character and is equivalent to the π-π^{⋆} band of graphene but with renormalized couplings. The conduction bands higher in energy have no counterpart in graphene; they combine a Dirac cone and flat bands because of their P-orbital character. We show that the width of the Dirac bands varies between tens and hundreds of meV. These systems emerge as remarkable platforms for studying complex electronic phases starting from conventional semiconductors. Recent advancements in colloidal chemistry indicate that these materials can be synthesized from semiconductor nanocrystals.
Fisher information and statistical inference for phase-type distributions
DEFF Research Database (Denmark)
Bladt, Mogens; Esparza, Luz Judith R; Nielsen, Bo Friis
2011-01-01
This paper is concerned with statistical inference for both continuous and discrete phase-type distributions. We consider maximum likelihood estimation, where traditionally the expectation-maximization (EM) algorithm has been employed. Certain numerical aspects of this method are revised and we...
Energy Technology Data Exchange (ETDEWEB)
Grattidge, W.; Westbrook, J.; McCarthy, J.; Northrup, C. Jr.; Rumble, J. Jr.
1986-11-01
The National Bureau of Standards and the Department of Energy have embarked on a program to build a demonstration computerized materials data system called Materials Information for Science and Technology (MIST). This report documents the first two phases of the project. The emphasis of the first phase was on determining what information was needed and how it could impact user productivity. The second phase data from the Aerospace Metal Handbook on a set of alloys was digitized and incorporated in the system.
Regional Dialogue on the Information Society (DIRSI) - Phase II ...
International Development Research Centre (IDRC) Digital Library (Canada)
The Regional Dialogue on the Information Society Network (DIRSI) is a ... the poorest sectors of society, the project will focus on innovative policy solutions ... their Impact on the Development of the Mobile Telecommunications Services Sector.
Weather Information Services supporting Civilian UAS Operations, Phase I
National Aeronautics and Space Administration — We build a system that supports the weather information needs of Unmanned Aircraft Systems (UAS) planning to fly in the National Airspace System (NAS). This weather...
Environmental information volume: Liquid Phase Methanol (LPMEOH{trademark}) project
Energy Technology Data Exchange (ETDEWEB)
NONE
1996-05-01
The purpose of this project is to demonstrate the commercial viability of the Liquid Phase Methanol Process using coal-derived synthesis gas, a mixture of hydrogen and carbon monoxide. This report describes the proposed actions, alternative to the proposed action, the existing environment at the coal gasification plant at Kingsport, Tennessee, environmental impacts, regulatory requirements, offsite fuel testing, and DME addition to methanol production. Appendices include the air permit application, solid waste permits, water permit, existing air permits, agency correspondence, and Eastman and Air Products literature.
Environmental information volume: Liquid Phase Methanol (LPMEOH trademark) project
International Nuclear Information System (INIS)
1996-05-01
The purpose of this project is to demonstrate the commercial viability of the Liquid Phase Methanol Process using coal-derived synthesis gas, a mixture of hydrogen and carbon monoxide. This report describes the proposed actions, alternative to the proposed action, the existing environment at the coal gasification plant at Kingsport, Tennessee, environmental impacts, regulatory requirements, offsite fuel testing, and DME addition to methanol production. Appendices include the air permit application, solid waste permits, water permit, existing air permits, agency correspondence, and Eastman and Air Products literature
Effective action of heterotic compactification on K3 with non-trivial gauge bundles
International Nuclear Information System (INIS)
Schasny, Martin
2012-10-01
In this thesis we study the heterotic string compactified on K3 with non-trivial gauge bundles. We focus on two backgrounds, the well-known standard embedding and abelian line bundles. Using a Kaluza-Klein reduction, the six-dimensional effective action is computed up to terms of order α' 2 with special attention on the hypermultiplet sector. We compute the moduli dependent couplings of the matter fields and analyze the geometry of the hyperscalar sigma model. Moreover, we prove the consistency with six-dimensional supergravity and derive the appropriate D-term scalar potential. For the line bundle backgrounds we show that the gauge flux stabilizes some geometrical moduli and renders some abelian vector multiplets massive.
Topologically non-trivial electronic and magnetic states in doped copper Kagome lattices
Guterding, Daniel; Jeschke, Harald O.; Valenti, Roser
We present a theoretical investigation of doped copper kagome materials based on natural minerals Herbertsmithite [ZnCu3(OH)6Cl2] and Barlowite[Cu4(OH)6FBr]. Using ab-initio density functional theory calculations we estimate the stability of the hypothetical compounds against structural distortions and analyze their electronic and magnetic properties. We find that materials based on Herbertsmithite present an ideal playground for investigating the interplay of non-trivial band-topology and strong electronic correlation effects. In particular, we propose candidates for the Quantum Spin Hall effect at filling 4/3 and the Quantum Anomalous Hall effect at filling 2/3. For the Barlowite system we point out a route to realize a Quantum Spin Liquid. This work was supported by Deutsche Forschungsgemeinschaft under Grant No. SFB/TR 49 and the National Science Foundation under Grant No. PHY11-25915.
Effective action of heterotic compactification on K3 with non-trivial gauge bundles
Energy Technology Data Exchange (ETDEWEB)
Schasny, Martin
2012-10-15
In this thesis we study the heterotic string compactified on K3 with non-trivial gauge bundles. We focus on two backgrounds, the well-known standard embedding and abelian line bundles. Using a Kaluza-Klein reduction, the six-dimensional effective action is computed up to terms of order {alpha}'{sup 2} with special attention on the hypermultiplet sector. We compute the moduli dependent couplings of the matter fields and analyze the geometry of the hyperscalar sigma model. Moreover, we prove the consistency with six-dimensional supergravity and derive the appropriate D-term scalar potential. For the line bundle backgrounds we show that the gauge flux stabilizes some geometrical moduli and renders some abelian vector multiplets massive.
The Path Resistance Method for Bounding the Smallest Nontrivial Eigenvalue of a Laplacian
Guattery, Stephen; Leighton, Tom; Miller, Gary L.
1997-01-01
We introduce the path resistance method for lower bounds on the smallest nontrivial eigenvalue of the Laplacian matrix of a graph. The method is based on viewing the graph in terms of electrical circuits; it uses clique embeddings to produce lower bounds on lambda(sub 2) and star embeddings to produce lower bounds on the smallest Rayleigh quotient when there is a zero Dirichlet boundary condition. The method assigns priorities to the paths in the embedding; we show that, for an unweighted tree T, using uniform priorities for a clique embedding produces a lower bound on lambda(sub 2) that is off by at most an 0(log diameter(T)) factor. We show that the best bounds this method can produce for clique embeddings are the same as for a related method that uses clique embeddings and edge lengths to produce bounds.
Bai, Jianying; Dong, Xue; He, Sheng; Bao, Min
2017-06-03
Ocular dominance has been extensively studied, often with the goal to understand neuroplasticity, which is a key characteristic within the critical period. Recent work on monocular deprivation, however, demonstrates residual neuroplasticity in the adult visual cortex. After deprivation of patterned inputs by monocular patching, the patched eye becomes more dominant. Since patching blocks both the Fourier amplitude and phase information of the input image, it remains unclear whether deprivation of the Fourier phase information alone is able to reshape eye dominance. Here, for the first time, we show that removing of the phase regularity without changing the amplitude spectra of the input image induced a shift of eye dominance toward the deprived eye, but only if the eye dominance was measured with a binocular rivalry task rather than an interocular phase combination task. These different results indicate that the two measurements are supported by different mechanisms. Phase integration requires the fusion of monocular images. The fused percept highly relies on the weights of the phase-sensitive monocular neurons that respond to the two monocular images. However, binocular rivalry reflects the result of direct interocular competition that strongly weights the contour information transmitted along each monocular pathway. Monocular phase deprivation may not change the weights in the integration (fusion) mechanism much, but alters the balance in the rivalry (competition) mechanism. Our work suggests that ocular dominance plasticity may occur at different stages of visual processing, and that homeostatic compensation also occurs for the lack of phase regularity in natural scenes. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.
Method of bistable optical information storage using antiferroelectric phase PLZT ceramics
Land, Cecil E.
1990-01-01
A method for bistable storage of binary optical information includes an antiferroelectric (AFE) lead lanthanum zirconate titanate (PLZT) layer having a stable antiferroelectric first phase and a ferroelectric (FE) second phase obtained by applying a switching electric field across the surface of the device. Optical information is stored by illuminating selected portions of the layer to photoactivate an FE to AFE transition in those portions. Erasure of the stored information is obtained by reapplying the switching field.
Secure quantum private information retrieval using phase-encoded queries
Energy Technology Data Exchange (ETDEWEB)
Olejnik, Lukasz [CERN, 1211 Geneva 23, Switzerland and Poznan Supercomputing and Networking Center, Noskowskiego 12/14, PL-61-704 Poznan (Poland)
2011-08-15
We propose a quantum solution to the classical private information retrieval (PIR) problem, which allows one to query a database in a private manner. The protocol offers privacy thresholds and allows the user to obtain information from a database in a way that offers the potential adversary, in this model the database owner, no possibility of deterministically establishing the query contents. This protocol may also be viewed as a solution to the symmetrically private information retrieval problem in that it can offer database security (inability for a querying user to steal its contents). Compared to classical solutions, the protocol offers substantial improvement in terms of communication complexity. In comparison with the recent quantum private queries [Phys. Rev. Lett. 100, 230502 (2008)] protocol, it is more efficient in terms of communication complexity and the number of rounds, while offering a clear privacy parameter. We discuss the security of the protocol and analyze its strengths and conclude that using this technique makes it challenging to obtain the unconditional (in the information-theoretic sense) privacy degree; nevertheless, in addition to being simple, the protocol still offers a privacy level. The oracle used in the protocol is inspired both by the classical computational PIR solutions as well as the Deutsch-Jozsa oracle.
Secure quantum private information retrieval using phase-encoded queries
International Nuclear Information System (INIS)
Olejnik, Lukasz
2011-01-01
We propose a quantum solution to the classical private information retrieval (PIR) problem, which allows one to query a database in a private manner. The protocol offers privacy thresholds and allows the user to obtain information from a database in a way that offers the potential adversary, in this model the database owner, no possibility of deterministically establishing the query contents. This protocol may also be viewed as a solution to the symmetrically private information retrieval problem in that it can offer database security (inability for a querying user to steal its contents). Compared to classical solutions, the protocol offers substantial improvement in terms of communication complexity. In comparison with the recent quantum private queries [Phys. Rev. Lett. 100, 230502 (2008)] protocol, it is more efficient in terms of communication complexity and the number of rounds, while offering a clear privacy parameter. We discuss the security of the protocol and analyze its strengths and conclude that using this technique makes it challenging to obtain the unconditional (in the information-theoretic sense) privacy degree; nevertheless, in addition to being simple, the protocol still offers a privacy level. The oracle used in the protocol is inspired both by the classical computational PIR solutions as well as the Deutsch-Jozsa oracle.
Building information modeling in the architectural design phases
DEFF Research Database (Denmark)
Hermund, Anders
2009-01-01
The overall economical benefits of Building Information Modeling are generally comprehensible, but are there other problems with the implementation of BIM as a formulized system in a field that ultimately is dependant on a creative input? Is optimization and economic benefit really contributing...... with an architectural quality? In Denmark the implementation of the digital working methods related to BIM has been introduced by government law in 2007. Will the important role of the architect as designer change in accordance with these new methods, and does the idea of one big integrated model represent a paradox...... in relation to designing? The BIM mindset requires changes on many levels....
Adaptive DSPI phase denoising using mutual information and 2D variational mode decomposition
Xiao, Qiyang; Li, Jian; Wu, Sijin; Li, Weixian; Yang, Lianxiang; Dong, Mingli; Zeng, Zhoumo
2018-04-01
In digital speckle pattern interferometry (DSPI), noise interference leads to a low peak signal-to-noise ratio (PSNR) and measurement errors in the phase map. This paper proposes an adaptive DSPI phase denoising method based on two-dimensional variational mode decomposition (2D-VMD) and mutual information. Firstly, the DSPI phase map is subjected to 2D-VMD in order to obtain a series of band-limited intrinsic mode functions (BLIMFs). Then, on the basis of characteristics of the BLIMFs and in combination with mutual information, a self-adaptive denoising method is proposed to obtain noise-free components containing the primary phase information. The noise-free components are reconstructed to obtain the denoising DSPI phase map. Simulation and experimental results show that the proposed method can effectively reduce noise interference, giving a PSNR that is higher than that of two-dimensional empirical mode decomposition methods.
Phases of information release during black hole evaporation
International Nuclear Information System (INIS)
Brustein, Ram; Medved, A.J.M.
2014-01-01
In a recent article, we have shown how quantum fluctuations of the background geometry modify Hawking’s density matrix for black hole (BH) radiation. Hawking’s diagonal matrix picks up small off-diagonal elements whose influence becomes larger with the number of emitted particles. We have calculated the “time-of-first-bit', when the first bit of information comes out of the BH, and the “transparency time', when the rate of information release becomes order unity. We have found that the transparency time is equal to the “Page time”, when the BH has lost half of its initial entropy to the radiation, in agreement with Page’s results. Here, we improve our previous calculation by keeping track of the time of emission of the Hawking particles and their back-reaction on the BH. Our analysis reveals a new time scale, the radiation “coherence time”, which is equal to the geometric mean of the evaporation time and the light crossing time. We find, as for our previous treatment, that the time-of-first-bit is equal to the coherence time, which is much shorter than the Page time. But the transparency time is now much later than the Page time, just one coherence time before the end of evaporation. Close to the end, when the BH is parametrically of Planckian dimensions but still large, the coherence time becomes parametrically equal to the evaporation time, thus allowing the radiation to purify. We also determine the time dependence of the entanglement entropy of the early and late-emitted radiation. This entropy is small during most of the lifetime of the BH, but our qualitative analysis suggests that it becomes parametrically maximal near the end of evaporation
Intelligent Information Processing for Enhanced Safety in the NAS, Phase II
National Aeronautics and Space Administration — Our Phase I work focused on how improved information flow between actors in a flight deck environment can improve safety performance. An operational prototype was...
An Exploratory Study of Informal Learning and Team Performance in the Pre-Consulting Phase
Sibarani, Roza Marsaulina
2014-01-01
This paper reports the process of informal learning in the pre-consulting phase in management-consulting firms in Indonesia. As the consulting industry significantly grows in Indonesia, more organisations use consultant services to improve their business. Pre-consulting is an important phase to define the right solutions, which involves a lot of…
International Nuclear Information System (INIS)
French, Doug; Huang Zun; Pao, H.-Y.; Jovanovic, Igor
2009-01-01
A quantum phase amplifier operated in the spatial domain can improve the signal-to-noise ratio in imaging beyond the classical limit. The scaling of the signal-to-noise ratio with the gain of the quantum phase amplifier is derived from classical information theory
Scaling of quantum Fisher information close to the quantum phase transition in the XY spin chain
Energy Technology Data Exchange (ETDEWEB)
Ye, En-Jia, E-mail: yeenjia@jiangnan.edu.cn [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China); Hu, Zheng-Da [Jiangsu Provincial Research Center of Light Industrial Optoelectronic Engineering and Technology, School of Science, Jiangnan University, Wuxi 214122 (China); Wu, Wei [Zhejiang Institute of Modern Physics and Physics Department, Zhejiang University, Hangzhou 310027 (China)
2016-12-01
The quantum phase transition of an XY spin chain is investigated by employing the quantum Fisher information encoded in the ground state. It is shown that the quantum Fisher information is an effective tool for characterizing the quantum criticality. The quantum Fisher information, its first and second derivatives versus the transverse field display the phenomena of sudden transition, sudden jump and divergence, respectively. Besides, the analysis of finite size scaling for the second derivative of quantum Fisher information is performed.
Xu, Guizhou; Wang, Wenhong; Zhang, Xiaoming; Du, Yin; Liu, Enke; Wang, Shouguo; Wu, Guangheng; Liu, Zhongyuan; Zhang, Xixiang
2014-01-01
A large number of half-Heusler compounds have been recently proposed as three-dimensional (3D) topological insulators (TIs) with tunable physical properties. However, no transport measurements associated with the topological surface states have been observed in these half-Heusler candidates due to the dominating contribution from bulk electrical conductance. Here we show that, by reducing the mobility of bulk carriers, a two-dimensional (2D) weak antilocalization (WAL) effect, one of the hallmarks of topological surface states, was experimentally revealed from the tilted magnetic field dependence of magnetoconductance in a topologically nontrivial semimetal LuPdBi. Besides the observation of a 2D WAL effect, a superconducting transition was revealed at T c ∼ 1.7â.K in the same bulk LuPdBi. Quantitative analysis within the framework of a generalized BCS theory leads to the conclusion that the noncentrosymmetric superconductivity of LuPdBi is fully gapped with a possibly unconventional pairing character. The co-existence of superconductivity and the transport signature of topological surface states in the same bulk alloy suggests that LuPdBi represents a very promising candidate as a topological superconductor.
Xu, Guizhou
2014-07-21
A large number of half-Heusler compounds have been recently proposed as three-dimensional (3D) topological insulators (TIs) with tunable physical properties. However, no transport measurements associated with the topological surface states have been observed in these half-Heusler candidates due to the dominating contribution from bulk electrical conductance. Here we show that, by reducing the mobility of bulk carriers, a two-dimensional (2D) weak antilocalization (WAL) effect, one of the hallmarks of topological surface states, was experimentally revealed from the tilted magnetic field dependence of magnetoconductance in a topologically nontrivial semimetal LuPdBi. Besides the observation of a 2D WAL effect, a superconducting transition was revealed at T c ∼ 1.7â.K in the same bulk LuPdBi. Quantitative analysis within the framework of a generalized BCS theory leads to the conclusion that the noncentrosymmetric superconductivity of LuPdBi is fully gapped with a possibly unconventional pairing character. The co-existence of superconductivity and the transport signature of topological surface states in the same bulk alloy suggests that LuPdBi represents a very promising candidate as a topological superconductor.
Layer-by-layer assembly of patchy particles as a route to nontrivial structures
Patra, Niladri; Tkachenko, Alexei V.
2017-08-01
We propose a strategy for robust high-quality self-assembly of nontrivial periodic structures out of patchy particles and investigate it with Brownian dynamics simulations. Its first element is the use of specific patch-patch and shell-shell interactions between the particles, which can be implemented through differential functionalization of patched and shell regions with specific DNA strands. The other key element of our approach is the use of a layer-by-layer protocol that allows one to avoid the formation of undesired random aggregates. As an example, we design and self-assemble in silico a version of a double diamond lattice in which four particle types are arranged into bcc crystal made of four fcc sublattices. The lattice can be further converted to cubic diamond by selective removal of the particles of certain types. Our results demonstrate that by combining the directionality, selectivity of interactions, and the layer-by-layer protocol, a high-quality robust self-assembly can be achieved.
Wang, Jeen-Shing; Lin, Che-Wei; Yang, Ya-Ting C; Ho, Yu-Jen
2012-10-01
This paper presents a walking pattern classification and a walking distance estimation algorithm using gait phase information. A gait phase information retrieval algorithm was developed to analyze the duration of the phases in a gait cycle (i.e., stance, push-off, swing, and heel-strike phases). Based on the gait phase information, a decision tree based on the relations between gait phases was constructed for classifying three different walking patterns (level walking, walking upstairs, and walking downstairs). Gait phase information was also used for developing a walking distance estimation algorithm. The walking distance estimation algorithm consists of the processes of step count and step length estimation. The proposed walking pattern classification and walking distance estimation algorithm have been validated by a series of experiments. The accuracy of the proposed walking pattern classification was 98.87%, 95.45%, and 95.00% for level walking, walking upstairs, and walking downstairs, respectively. The accuracy of the proposed walking distance estimation algorithm was 96.42% over a walking distance.
Smith, Edward M.; Wandtke, John; Robinson, Arvin E.
1999-07-01
The Medical Information, Communication and Archive System (MICAS) is a multi-modality integrated image management system that is seamlessly integrated with the Radiology Information System (RIS). This project was initiated in the summer of 1995 with the first phase being installed during the first half of 1997 and the second phase installed during the summer of 1998. Phase II enhancements include a permanent archive, automated workflow including modality worklist, study caches, NT diagnostic workstations with all components adhering to Digital Imaging and Communications in Medicine (DICOM) standards. This multi-vendor phased approach to PACS implementation is designed as an enterprise-wide PACS to provide images and reports throughout our healthcare network. MICAS demonstrates that aa multi-vendor open system phased approach to PACS is feasible, cost-effective, and has significant advantages over a single vendor implementation.
International Nuclear Information System (INIS)
Jung, V.
1982-07-01
Drawing annealed cylindric 18/8 Cr Ni steels, which are originally free of textures, produces the transformed phases - hcp and bcc - both showing major texture contributions with increasing stretching of the cylindric specimens. After stretching the original fcc-phase shows two orientations: [100]fcc vertical stroke vertical stroke cylinder axis and [111]fcc vertical stroke vertical stroke cylinder axis, i.e. direction of stress. In both cases the martensitic phase is produced by gliding and shear in the sequence fcc → hcp → bcc by Nishiyama-Wasserman (N-W) or Kurdjumov-Sachs (K-S) transformation in the (111)fcc planes, which enclose a small angle with direction of stress, i.e. cylinder axis. The calculated orientation distributions of the (110)bcc reflex are compared with the distribution measured by neutron diffraction to get information on the bulk material. The special K-S transformation with only 6 (110)bcc orientations shows relatively good agreement with the measured distribution, except at small angles ω between the cylinder axis and the scattering vector. This might be caused by the isotropic fraction of the fcc phase producing an anisotropic (110)bcc orientation distribution. (orig.) [de
Directory of Open Access Journals (Sweden)
Masahiro eKawasaki
2014-03-01
Full Text Available Electroencephalogram (EEG phase synchronization analyses can reveal large-scale communication between distant brain areas. However, it is not possible to identify the directional information flow between distant areas using conventional phase synchronization analyses. In the present study, we applied transcranial magnetic stimulation (TMS to the occipital area in subjects who were resting with their eyes closed, and analyzed the spatial propagation of transient TMS-induced phase resetting by using the transfer entropy (TE, to quantify the causal and directional flow of information. The time-frequency EEG analysis indicated that the theta (5 Hz phase locking factor (PLF reached its highest value at the distant area (the motor area in this study, with a time lag that followed the peak of the transient PLF enhancements of the TMS-targeted area at the TMS onset. PPI (phase-preservation index analyses demonstrated significant phase resetting at the TMS-targeted area and distant area. Moreover, the TE from the TMS-targeted area to the distant area increased clearly during the delay that followed TMS onset. Interestingly, the time lags were almost coincident between the PLF and TE results (152 vs. 165 ms, which provides strong evidence that the emergence of the delayed PLF reflects the causal information flow. Such tendencies were observed only in the higher-intensity TMS condition, and not in the lower-intensity or sham TMS conditions. Thus, TMS may manipulate large-scale causal relationships between brain areas in an intensity-dependent manner. We demonstrated that single-pulse TMS modulated global phase dynamics and directional information flow among synchronized brain networks. Therefore, our results suggest that single-pulse TMS can manipulate both incoming and outgoing information in the TMS-targeted area associated with functional changes.
Besserve, Michel; Lowe, Scott C; Logothetis, Nikos K; Schölkopf, Bernhard; Panzeri, Stefano
2015-01-01
Distributed neural processing likely entails the capability of networks to reconfigure dynamically the directionality and strength of their functional connections. Yet, the neural mechanisms that may allow such dynamic routing of the information flow are not yet fully understood. We investigated the role of gamma band (50-80 Hz) oscillations in transient modulations of communication among neural populations by using measures of direction-specific causal information transfer. We found that the local phase of gamma-band rhythmic activity exerted a stimulus-modulated and spatially-asymmetric directed effect on the firing rate of spatially separated populations within the primary visual cortex. The relationships between gamma phases at different sites (phase shifts) could be described as a stimulus-modulated gamma-band wave propagating along the spatial directions with the largest information transfer. We observed transient stimulus-related changes in the spatial configuration of phases (compatible with changes in direction of gamma wave propagation) accompanied by a relative increase of the amount of information flowing along the instantaneous direction of the gamma wave. These effects were specific to the gamma-band and suggest that the time-varying relationships between gamma phases at different locations mark, and possibly causally mediate, the dynamic reconfiguration of functional connections.
International Nuclear Information System (INIS)
Kjellander, Roland; Ramirez, Rosa
2008-01-01
An exact treatment of screened electrostatics in electrolyte solutions is presented. In electrolytes the anisotropy of the exponentially decaying electrostatic potential from a molecule extends to the far field region. The full directional dependence of the electrostatic potential from a charged or uncharged molecule remains in the longest range tail (i.e. from all multipole moments). In particular, the range of the potential from an ion and that from an electroneutral polar particle is generally exactly the same. This is in contrast to the case in vacuum or pure polar liquids, where the potential from a single charge is longer ranged than that from a dipole, which is, itself, longer ranged than the one from a quadrupole etc. The orientational dependence of the exponentially screened electrostatic interaction between two molecules in electrolytes is therefore rather complex even at long distances. These facts are formalized in Yukawa multipole expansions of the electrostatic potential and the pair interaction free energy based on the Yukawa function family exp(-κr)/r m , where r is the distance, κ is a decay parameter and m is a positive integer. The expansion is formally exact for electrolytes with molecular solvent and in the primitive model, provided the non-Coulombic interactions between the particles are sufficiently short ranged. The results can also be applied in the Poisson-Boltzmann approximation. Differences and similarities to the ordinary multipole expansion of electrostatics are pointed out. On the other hand, when the non-Coulombic interactions between the constituent particles of the electrolyte solution contain a dispersion 1/r 6 potential, the electrostatic potential from a molecule decays like a power law for long distances rather than as a Yukawa function. This is due to nontrivial coupling between the electrostatic and dispersion interactions. There remains an exponentially decaying component in the electrostatic potential, but it becomes
Contractions without non-trivial invariant subspaces satisfying a positivity condition
Directory of Open Access Journals (Sweden)
Bhaggy Duggal
2016-04-01
Full Text Available Abstract An operator A ∈ B ( H $A\\in B(\\mathcal{H}$ , the algebra of bounded linear transformations on a complex infinite dimensional Hilbert space H $\\mathcal{H}$ , belongs to class A ( n $\\mathcal{A}(n$ (resp., A ( ∗ − n $\\mathcal{A}(*-n$ if | A | 2 ≤ | A n + 1 | 2 n + 1 $\\vert A\\vert^{2}\\leq\\vert A^{n+1}\\vert^{\\frac{2}{n+1}}$ (resp., | A ∗ | 2 ≤ | A n + 1 | 2 n + 1 $\\vert A^{*}\\vert^{2}\\leq \\vert A^{n+1}\\vert^{\\frac{2}{n+1}}$ for some integer n ≥ 1 $n\\geq1$ , and an operator A ∈ B ( H $A\\in B(\\mathcal{H}$ is called n-paranormal, denoted A ∈ P ( n $A\\in \\mathcal{P}(n$ (resp., ∗ − n $*-n$ -paranormal, denoted A ∈ P ( ∗ − n $A\\in \\mathcal{P}(*-n$ if ∥ A x ∥ n + 1 ≤ ∥ A n + 1 x ∥ ∥ x ∥ n $\\Vert Ax\\Vert ^{n+1}\\leq \\Vert A^{n+1}x\\Vert \\Vert x\\Vert ^{n}$ (resp., ∥ A ∗ x ∥ n + 1 ≤ ∥ A n + 1 x ∥ ∥ x ∥ n $\\Vert A^{*}x\\Vert ^{n+1}\\leq \\Vert A^{n+1}x\\Vert \\Vert x\\Vert ^{n}$ for some integer n ≥ 1 $n\\geq 1$ and all x ∈ H $x \\in\\mathcal{H}$ . In this paper, we prove that if A ∈ { A ( n ∪ P ( n } $A\\in\\{\\mathcal{A}(n\\cup \\mathcal{P}(n\\}$ (resp., A ∈ { A ( ∗ − n ∪ P ( ∗ − n } $A\\in\\{\\mathcal{A}(*-n\\cup \\mathcal{P}(*-n\\}$ is a contraction without a non-trivial invariant subspace, then A, | A n + 1 | 2 n + 1 − | A | 2 $\\vert A^{n+1}\\vert^{\\frac{2}{n+1}}-\\vert A\\vert^{2}$ and | A n + 1 | 2 − n + 1 n | A | 2 + 1 $\\vert A^{n+1}\\vert^{2}- {\\frac{n+1}{n}}\\vert A\\vert^{2}+ 1$ (resp., A, | A n + 1 | 2 n + 1 − | A ∗ | 2 $\\vert A^{n+1}\\vert^{\\frac{2}{n+1}}-\\vert A^{*}\\vert^{2}$ and | A n + 2 | 2 − n + 1 n | A | 2 + 1 ≥ 0 $\\vert A^{n+2}\\vert^{2}- {\\frac{n+1}{n}}\\vert A\\vert^{2}+ 1\\geq0$ are proper contractions.
Phase retrieval from diffraction data utilizing pre-determined partial information
International Nuclear Information System (INIS)
Kim, S.S.; Marathe, S.; Kim, S.N.; Kang, H.C.; Noh, D.Y.
2007-01-01
We developed a phase retrieval algorithm that utilizes pre-determined partial phase information to overcome insufficient oversampling ratio in diffraction data. Implementing the Fourier modulus projection and the modified support projection manifesting the pre-determined information, a generalized difference map and HIO (Hybrid Input-Output) algorithms are developed. Optical laser diffraction data as well as simulated X-ray diffraction data are used to illustrate the validity of the proposed algorithm, which revealed the strength and the limitations of the algorithm. The proposed algorithm can expand the applicability of the diffraction based image reconstruction
Information hiding based on double random-phase encoding and public-key cryptography.
Sheng, Yuan; Xin, Zhou; Alam, Mohammed S; Xi, Lu; Xiao-Feng, Li
2009-03-02
A novel information hiding method based on double random-phase encoding (DRPE) and Rivest-Shamir-Adleman (RSA) public-key cryptosystem is proposed. In the proposed technique, the inherent diffusion property of DRPE is cleverly utilized to make up the diffusion insufficiency of RSA public-key cryptography, while the RSA cryptosystem is utilized for simultaneous transmission of the cipher text and the two phase-masks, which is not possible under the DRPE technique. This technique combines the complementary advantages of the DPRE and RSA encryption techniques and brings security and convenience for efficient information transmission. Extensive numerical simulation results are presented to verify the performance of the proposed technique.
International Nuclear Information System (INIS)
Barthelmess, H.; Queren, W.; Stracke, M.
1989-01-01
The structure and function of the Information AAssociation for Welding Engineering, newly established by the Deutscher Verband fuer Schweisstechnik, are presented. Examined are: special literature for welding techniques - value and prospects; databases accessible to the public for information on welding techniques; concept for the Information Association for Welding Engineering; the four phases to establish databasis for facts and expert systems of the Information Association for Welding Engineering; the pilot project 'MVT-Data base' (hot crack data base for data of modified varestraint-transvarestraint tests). (orig./MM) [de
Brown, Richard; Bylund, Carma L; Siminoff, Laura A; Slovin, Susan F
2011-04-01
Phase I clinical trials are the gateway to effective new cancer treatments. Many physicians have difficulty when discussing Phase I clinical trials. Research demonstrates evidence of suboptimal communication. Little is known about communication strategies used by oncologists when recruiting patients for Phase I trials. We analyzed audio recorded Phase I consultations to identify oncologists' communication strategies. Subjects were consecutive cancer patients from six medical oncologists attending one of three outpatient clinics at a major Cancer Center in the United States. Sixteen patients signed informed consent for audio recording of their consultations in which a Phase I study was discussed. These were transcribed in full and analyzed to identify communication strategies. Six communication themes emerged from the analysis: (1) orienting, (2) educating patients, (3) describing uncertainty and prognosis, (4) persuading, (5) decision making, and (6) making a treatment recommendation. As expected, although there was some common ground between communication in Phase I and the Phase II and III settings, there were distinct differences. Oncologists used persuasive communication, made explicit recommendations, or implicitly expressed a treatment preference and were choice limiting. This highlights the complexity of discussing Phase I trials and the need to develop strategies to aid oncologists and patients in these difficult conversations. Patient centered communication that values patient preferences while preserving the oncologist's agenda can be a helpful approach to these discussions. Copyright © 2010 John Wiley & Sons, Ltd.
Kasim, N.; Zainal Abidin, N. A.; Zainal, R.; Sarpin, N.; Rahim, M. H. I. Abd; Saikah, M.
2017-11-01
Implementation of Building Information Modelling (BIM) was expected to bring improvement in current practices of Malaysian construction industry. In the design phase, there is a lack of a ready pool of skilled workers who are able to develop BIM strategic plan and effectively utilise it. These create boundaries for BIM nature in Malaysian construction industry specifically in the design phase to achieve its best practices. Therefore, the objectives of this research are to investigate the current practices of BIM implementation in the design phase as well as the best practices factors of BIM implementation in the design phase. The qualitative research approach is carried out through semi-structured interviews with the designers of different organisations which adopt BIM in the design phase. Data collection is analysed by executing content analysis method. From the findings, the best practices factors of BIM implementation in design phase such as the incentive for BIM training, formal approach to monitoring automated Level of Detailing (LOD), run a virtual meeting and improve Industry Foundation Class (IFC). Thus, best practices factors which lead to practices improvements in the design phase of project development which subsequently improves the implementation of BIM in the design phase of Malaysian construction industry.
International Nuclear Information System (INIS)
Afuwape, A.U.; Omari, P.
1987-11-01
This paper deals with the solvability of the nonlinear operator equations in normed spaces Lx=EGx+f, where L is a linear map with possible nontrivial kernel. Applications are given to the existence of periodic solutions for the third order scalar differential equation x'''+ax''+bx'+cx+g(t,x)=p(t), under various conditions on the interaction of g(t,x)/x with spectral configurations of a, b and c. (author). 48 refs
Direction of coupling from phases of interacting oscillators: An information-theoretic approach
Paluš, Milan; Stefanovska, Aneta
2003-05-01
A directionality index based on conditional mutual information is proposed for application to the instantaneous phases of weakly coupled oscillators. Its abilities to distinguish unidirectional from bidirectional coupling, as well as to reveal and quantify asymmetry in bidirectional coupling, are demonstrated using numerical examples of quasiperiodic, chaotic, and noisy oscillators, as well as real human cardiorespiratory data.
Hoyer, Dirk; Leder, Uwe; Hoyer, Heike; Pompe, Bernd; Sommer, Michael; Zwiener, Ulrich
2002-01-01
The heart rate variability (HRV) is related to several mechanisms of the complex autonomic functioning such as respiratory heart rate modulation and phase dependencies between heart beat cycles and breathing cycles. The underlying processes are basically nonlinear. In order to understand and quantitatively assess those physiological interactions an adequate coupling analysis is necessary. We hypothesized that nonlinear measures of HRV and cardiorespiratory interdependencies are superior to the standard HRV measures in classifying patients after acute myocardial infarction. We introduced mutual information measures which provide access to nonlinear interdependencies as counterpart to the classically linear correlation analysis. The nonlinear statistical autodependencies of HRV were quantified by auto mutual information, the respiratory heart rate modulation by cardiorespiratory cross mutual information, respectively. The phase interdependencies between heart beat cycles and breathing cycles were assessed basing on the histograms of the frequency ratios of the instantaneous heart beat and respiratory cycles. Furthermore, the relative duration of phase synchronized intervals was acquired. We investigated 39 patients after acute myocardial infarction versus 24 controls. The discrimination of these groups was improved by cardiorespiratory cross mutual information measures and phase interdependencies measures in comparison to the linear standard HRV measures. This result was statistically confirmed by means of logistic regression models of particular variable subsets and their receiver operating characteristics.
Classical solutions with nontrivial holonomy in SU(2) LGT at T ≠ 0
International Nuclear Information System (INIS)
Ilgenfritz, E.-M.; Martemyanov, B.V.; Mueller-Preussker, M.; Veselov, A.I.
2002-01-01
We generate SU(2) lattice gauge fields at finite temperature and cool them in order to characterize the two phases by the occurrence of specific classical solutions. We apply two kinds of spatial boundary conditions: fixed holonomy and standard periodic b.c. For T c our findings concerning classical configurations semi-quantitatively agree for both types of boundary conditions. We find in the confinement phase a mixture of undissociated calorons with lumps of positive or negative half-integer topological charges
Search for new ternary Al, Ga or In containing phases using information forecasting system
International Nuclear Information System (INIS)
Kiseleva, N.N.; Burkhanov, G.S.
1989-01-01
Automated system of search for regularities in the formation of crystal phases and forecasting of new compounds with required properties, comprising data base on the properties of ternary inorganic compounds and cybernetic forecasting system, has been developed. General principles of operation of the developed information-forecasting system are considered. Efficiency of the system operation is shown, using as an example the search for new ternary compounds with aluminium, gallium and indium, crystallized in ZrNiAl, TiNiSi, ThCr 2 Si 2 , CaAl 2 Si 2 structural types. Results of the above-mentioned phases forecasting are shown
International Nuclear Information System (INIS)
Andrej, L.; Bednar, M.; Cernansky, M.
1999-01-01
The phenomenon of quantum teleportation is discussed with emphasis on its physical aspects. A brief introduction into the Einstein-Podolsky-Rosen (EPR) paradox is followed by Bohm's reformulation of the EPR paradox for the case of a physical system of two spins in the singlet state. A description of Bell's entangled spin states of two-particle systems of standard fermions as well as polarized photons is also given. In view of the fact that quantum teleportation has been realized experimentally mainly on photons, the next part of the paper is devoted to problems of generation and detection of two-photon Bell's entangled states. A detailed description of the process of quantum teleportation exploiting quantum entangled states follows. A classical formulation of the EPR paradox is given in the Appendix. (Z.J.)
Long-Term Information Management (LTIM) of Safeguards Data at Repositories: Phase II
International Nuclear Information System (INIS)
Haddal, Risa N.
2016-01-01
One of the challenges of implementing safeguards for geological repositories will be the long-term preservation of safeguards-related data for 100 years or more. While most countries considering the construction and operation of such facilities agree that safeguards information should be preserved, there are gaps with respect to standardized requirements, guidelines, timescales, and approaches. This study analyzes those gaps and explores research to clarify stakeholder needs, identify current policies, approaches, best practices and international standards, and explores existing safeguards information management infrastructure. The study also attempts to clarify what a safeguards data classification system might look like, how long data should be retained, and how information should be exchanged between stakeholders at different phases of a repository's life cycle. The analysis produced a variety of recommendations on what information to preserve, how to preserve it, where to store it, retention options and how to exchange information in the long term. Key findings include the use of the globally recognized international records management standard, ISO15489, for guidance on the development of information management systems, and the development of a Key Information File (KIF). The KIF could be used to identify only the most relevant, high-level safeguards information and the history of decision making about the repository. The study also suggests implementing on-site and off-site records storage in digital and physical form; developing a safeguards data classification system; long-term records retention with periodic reviews every 5 to 10 years during each phase of the repository life cycle; and establishing transition procedures well in advance so that data shepherds and records officers can transfer information with incoming facility managers effectively and efficiently. These and other recommendations are further analyzed in this study.
Directory of Open Access Journals (Sweden)
Enzo eBrunetti
2013-06-01
Full Text Available During monitoring of the discourse, the detection of the relevance of incoming lexical information could be critical for its incorporation to update mental representations in memory. Because, in these situations, the relevance for lexical information is defined by abstract rules that are maintained in memory, results critical to understand how an abstract level of knowledge maintained in mind mediates the detection of the lower-level semantic information. In the present study, we propose that neuronal oscillations participate in the detection of relevant lexical information, based on ‘kept in mind’ rules deriving from more abstract semantic information. We tested our hypothesis using an experimental paradigm that restricted the detection of relevance to inferences based on explicit information, thus controlling for ambiguities derived from implicit aspects. We used a categorization task, in which the semantic relevance was previously defined based on the congruency between a kept in mind category (abstract knowledge, and the lexical-semantic information presented. Our results show that during the detection of the relevant lexical information, phase synchronization of neuronal oscillations selectively increases in delta and theta frequency bands during the interval of semantic analysis. These increments were independent of the semantic category maintained in memory, had a temporal profile specific for each subject, and were mainly induced, as they had no effect on the evoked mean global field power. Also, recruitment of an increased number of pairs of electrodes was a robust observation during the detection of semantic contingent words. These results are consistent with the notion that the detection of relevant lexical information based on a particular semantic rule, could be mediated by increasing the global phase synchronization of neuronal oscillations, which may contribute to the recruitment of an extended number of cortical regions.
Brunetti, Enzo; Maldonado, Pedro E; Aboitiz, Francisco
2013-01-01
During monitoring of the discourse, the detection of the relevance of incoming lexical information could be critical for its incorporation to update mental representations in memory. Because, in these situations, the relevance for lexical information is defined by abstract rules that are maintained in memory, a central aspect to elucidate is how an abstract level of knowledge maintained in mind mediates the detection of the lower-level semantic information. In the present study, we propose that neuronal oscillations participate in the detection of relevant lexical information, based on "kept in mind" rules deriving from more abstract semantic information. We tested our hypothesis using an experimental paradigm that restricted the detection of relevance to inferences based on explicit information, thus controlling for ambiguities derived from implicit aspects. We used a categorization task, in which the semantic relevance was previously defined based on the congruency between a kept in mind category (abstract knowledge), and the lexical semantic information presented. Our results show that during the detection of the relevant lexical information, phase synchronization of neuronal oscillations selectively increases in delta and theta frequency bands during the interval of semantic analysis. These increments occurred irrespective of the semantic category maintained in memory, had a temporal profile specific for each subject, and were mainly induced, as they had no effect on the evoked mean global field power. Also, recruitment of an increased number of pairs of electrodes was a robust observation during the detection of semantic contingent words. These results are consistent with the notion that the detection of relevant lexical information based on a particular semantic rule, could be mediated by increasing the global phase synchronization of neuronal oscillations, which may contribute to the recruitment of an extended number of cortical regions.
Long-Term Information Management (LTIM) of Safeguards Data at Repositories: Phase II
Energy Technology Data Exchange (ETDEWEB)
Haddal, Risa N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2016-10-01
One of the challenges of implementing safeguards for geological repositories will be the long-term preservation of safeguards-related data for 100 years or more. While most countries considering the construction and operation of such facilities agree that safeguards information should be preserved, there are gaps with respect to standardized requirements, guidelines, timescales, and approaches. This study analyzes those gaps and explores research to clarify stakeholder needs, identify current policies, approaches, best practices and international standards, and explores existing safeguards information management infrastructure. The study also attempts to clarify what a safeguards data classification system might look like, how long data should be retained, and how information should be exchanged between stakeholders at different phases of a repository’s life cycle. The analysis produced a variety of recommendations on what information to preserve, how to preserve it, where to store it, retention options and how to exchange information in the long term. Key findings include the use of the globally recognized international records management standard, ISO15489, for guidance on the development of information management systems, and the development of a Key Information File (KIF). The KIF could be used to identify only the most relevant, high-level safeguards information and the history of decision making about the repository. The study also suggests implementing on-site and off-site records storage in digital and physical form; developing a safeguards data classification system; long-term records retention with periodic reviews every 5 to 10 years during each phase of the repository life cycle; and establishing transition procedures well in advance so that data shepherds and records officers can transfer information with incoming facility managers effectively and efficiently. These and other recommendations are further analyzed in this study.
Zeng, Fa; Tan, Qiaofeng; Yan, Yingbai; Jin, Guofan
2007-10-01
Study of phase retrieval technology is quite meaningful, for its wide applications related to many domains, such as adaptive optics, detection of laser quality, precise measurement of optical surface, and so on. Here a hybrid iterative phase retrieval algorithm is proposed, based on fusion of the intensity information in three defocused planes. First the conjugate gradient algorithm is adapted to achieve a coarse solution of phase distribution in the input plane; then the iterative angular spectrum method is applied in succession for better retrieval result. This algorithm is still applicable even when the exact shape and size of the aperture in the input plane are unknown. Moreover, this algorithm always exhibits good convergence, i.e., the retrieved results are insensitive to the chosen positions of the three defocused planes and the initial guess of complex amplitude in the input plane, which has been proved by both simulations and further experiments.
Architecture, des normes et des systèmes d'information libres, phase ...
International Development Research Centre (IDRC) Digital Library (Canada)
Architecture, des normes et des systèmes d'information libres, phase II (OASIS II) - Renforcement des capacités dans l'ensemble de l'Afrique. Sur presque tout le continent africain, la prestation des services de santé est limitée en raison des maigres ressources disponibles et de la charge de morbidité de plus en plus ...
Remarks on surfaces with $c_1^2 =2\\chi -1$ having non-trivial 2-torsion
MURAKAMI, Masaaki
2013-01-01
We shall show that any complex minimal surface of general type with $c_1^2 = 2\\chi -1$ having non-trivial 2-torsion divisors, where $c_1^2$ and $\\chi$ are the first Chern number of a surface and the Euler characteristic of the structure sheaf respectively, has the Euler characteristic $\\chi$ not exceeding 4. Moreover, we shall give a complete description for the surfaces of the case $\\chi =4$, and prove that the coarse moduli space for surfaces of this case is a unirational variety of dimensi...
Primordial non-Gaussianities in single field inflationary models with non-trivial initial states
Energy Technology Data Exchange (ETDEWEB)
Bahrami, Sina; Flanagan, Éanna É., E-mail: sb933@cornell.edu, E-mail: eef3@cornell.edu [Department of Physics, Cornell University, Ithaca, NY 14853 (United States)
2014-10-01
We compute the non-Gaussianities that arise in single field, slow roll inflationary models arising from arbitrary homogeneous initial states, as well as subleading contributions to the power spectrum. Non Bunch-Davies vacuum initial states can arise if the transition to the single field, slow roll inflation phase occurs only shortly before observable modes left the horizon. They can also arise from new physics at high energies that has been integrated out. Our general result for the bispectrum exhibits several features that were previously seen in special cases.
Inverse problems with non-trivial priors: efficient solution through sequential Gibbs sampling
DEFF Research Database (Denmark)
Hansen, Thomas Mejer; Cordua, Knud Skou; Mosegaard, Klaus
2012-01-01
Markov chain Monte Carlo methods such as the Gibbs sampler and the Metropolis algorithm can be used to sample solutions to non-linear inverse problems. In principle, these methods allow incorporation of prior information of arbitrary complexity. If an analytical closed form description of the prior...... is available, which is the case when the prior can be described by a multidimensional Gaussian distribution, such prior information can easily be considered. In reality, prior information is often more complex than can be described by the Gaussian model, and no closed form expression of the prior can be given....... We propose an algorithm, called sequential Gibbs sampling, allowing the Metropolis algorithm to efficiently incorporate complex priors into the solution of an inverse problem, also for the case where no closed form description of the prior exists. First, we lay out the theoretical background...
Valley Topological Phases in Bilayer Sonic Crystals
Lu, Jiuyang; Qiu, Chunyin; Deng, Weiyin; Huang, Xueqin; Li, Feng; Zhang, Fan; Chen, Shuqi; Liu, Zhengyou
2018-03-01
Recently, the topological physics in artificial crystals for classical waves has become an emerging research area. In this Letter, we propose a unique bilayer design of sonic crystals that are constructed by two layers of coupled hexagonal array of triangular scatterers. Assisted by the additional layer degree of freedom, a rich topological phase diagram is achieved by simply rotating scatterers in both layers. Under a unified theoretical framework, two kinds of valley-projected topological acoustic insulators are distinguished analytically, i.e., the layer-mixed and layer-polarized topological valley Hall phases, respectively. The theory is evidently confirmed by our numerical and experimental observations of the nontrivial edge states that propagate along the interfaces separating different topological phases. Various applications such as sound communications in integrated devices can be anticipated by the intriguing acoustic edge states enriched by the layer information.
International Nuclear Information System (INIS)
Ashtekar, A.; Sen, A.
1980-01-01
Schwarzschild--Kruskal space--time admits a two-parameter family of everywhere regular, static, source-free Maxwell fields. It is shown that there exists a corresponding two-parameter family of unitarily inequivalent representations of the canonical commutation relations. Elements of the underlying Hilbert space may be interpreted as ''quantum fluctuations of the Maxwell field off nontrivial classical vacua.'' The representation corresponding to the ''trivial'' sector: i.e., the zero classical solution: is the usual Fock representation. All others are ''non-Fock.'' In particular, in all other sectors, the Maxwell field develops a nonzero vacuum expectation value. The parameters labelling the family can be interpreted as electric and magnetic charges. Therefore, unitary inequivalence naturally leads to superselection rules for these charges. These features arise in spite of the linearity of field equations only because the space--time topology is ''nontrivial.'' Also, because of linearity, an exact analysis is possible at the quantum level; recourse to perturbation theory is unnecessary
Reentrant phase transitions and defensive alliances in social dilemmas with informed strategies
Szolnoki, Attila; Perc, Matjaž
2015-05-01
Knowing the strategy of an opponent in a competitive environment conveys obvious evolutionary advantages. But this information is costly, and the benefit of being informed may not necessarily offset the additional cost. Here we introduce social dilemmas with informed strategies, and we show that this gives rise to two cyclically dominant triplets that form defensive alliances. The stability of these two alliances is determined by the rotation velocity of the strategies within each triplet. A weaker strategy in a faster rotating triplet can thus overcome an individually stronger competitor. Fascinating spatial patterns favor the dominance of a single defensive alliance, but enable also the stable coexistence of both defensive alliances in very narrow regions of the parameter space. A continuous reentrant phase transition reveals before unseen complexity behind the stability of strategic alliances in evolutionary social dilemmas.
International Nuclear Information System (INIS)
Cabral, Leonardo Ribeiro Eulalio; Aguiar, Jose Albino Oliveira de
2002-01-01
Full text: The study of the electromagnetic response of high-T c superconductors is essential for future technological applications. Such materials are hard type II superconductors, where the mixed state (a state characterized by quantized normal flux tubes - also called vortices - immersed in a superconductor phase) occupies most of the phase diagram. Therefore, the electromagnetic properties are dictated by the vortex dynamics in these materials. One has also to consider the presence of structural defects and thermal effects, which turn the vortex dynamics very complex. These difficulties may be overcome throughout a macroscopic description, also known as continuum approximation, of the electromagnetic fields in superconductors, obtained from critical state models and constitutive relations E = E(j) and H = H(B) (where E is the electric field generated by moving vortices, j the current density, B the induction - related to the local density of vortices - and H the reversible magnetic field that is in equilibrium with B). In superconductors with negligible demagnetization factors, such as long cylinders and bars with applied magnetic fields and/or currents along their longer dimensions, the Meissner state and the flux penetration is quite well understood. However, the actual specimen shape plays an important role on the electromagnetic behavior of superconductors. Numerical methods are often employed, since such cases are hard to treat analytically. In this work we studied the electromagnetic response of superconductors with various shapes. The Meissner state is obtained for thin curved strips and long cylinders with arbitrary cross-section, in perpendicular field and with applied currents. The flux penetration is numerically calculated for thin curved strips for the Bean (j c =const.) and the Kim (j c (B) = j c0 /(1 + βB)) models. (author)
Lardner, Timothy; Li, Minghui; Gachagan, Anthony
2014-02-01
Materials with a coarse grain structure are becoming increasingly prevalent in industry due to their resilience to stress and corrosion. These materials are difficult to inspect with ultrasound because reflections from the grains lead to high noise levels which hinder the echoes of interest. Spatially Averaged Sub-Aperture Correlation Imaging (SASACI) is an advanced array beamforming technique that uses the cross-correlation between images from array sub-apertures to generate an image weighting matrix, in order to reduce noise levels. This paper presents a method inspired by SASACI to further improve imaging using phase information to refine focusing and reduce noise. A-scans from adjacent array elements are cross-correlated using both signal amplitude and phase to refine delay laws and minimize phase aberration. The phase-based and amplitude-based corrected images are used as inputs to a two-dimensional cross-correlation algorithm that will output a weighting matrix that can be applied to any conventional image. This approach was validated experimentally using a 5MHz array a coarse grained Inconel 625 step wedge, and compared to the Total Focusing Method (TFM). Initial results have seen SNR improvements of over 20dB compared to TFM, and a resolution that is much higher.
Energy Technology Data Exchange (ETDEWEB)
Lardner, Timothy; Gachagan, Anthony [Centre for Ultrasonic Engineering, University of Strathclyde, Glasgow, G1 1XW (United Kingdom); Li, Minghui [School of Engineering, University of Glasgow, Glasgow, G12 8QQ (United Kingdom)
2014-02-18
Materials with a coarse grain structure are becoming increasingly prevalent in industry due to their resilience to stress and corrosion. These materials are difficult to inspect with ultrasound because reflections from the grains lead to high noise levels which hinder the echoes of interest. Spatially Averaged Sub-Aperture Correlation Imaging (SASACI) is an advanced array beamforming technique that uses the cross-correlation between images from array sub-apertures to generate an image weighting matrix, in order to reduce noise levels. This paper presents a method inspired by SASACI to further improve imaging using phase information to refine focusing and reduce noise. A-scans from adjacent array elements are cross-correlated using both signal amplitude and phase to refine delay laws and minimize phase aberration. The phase-based and amplitude-based corrected images are used as inputs to a two-dimensional cross-correlation algorithm that will output a weighting matrix that can be applied to any conventional image. This approach was validated experimentally using a 5MHz array a coarse grained Inconel 625 step wedge, and compared to the Total Focusing Method (TFM). Initial results have seen SNR improvements of over 20dB compared to TFM, and a resolution that is much higher.
Optically secured information retrieval using two authenticated phase-only masks.
Wang, Xiaogang; Chen, Wen; Mei, Shengtao; Chen, Xudong
2015-10-23
We propose an algorithm for jointly designing two phase-only masks (POMs) that allow for the encryption and noise-free retrieval of triple images. The images required for optical retrieval are first stored in quick-response (QR) codes for noise-free retrieval and flexible readout. Two sparse POMs are respectively calculated from two different images used as references for authentication based on modified Gerchberg-Saxton algorithm (GSA) and pixel extraction, and are then used as support constraints in a modified double-phase retrieval algorithm (MPRA), together with the above-mentioned QR codes. No visible information about the target images or the reference images can be obtained from each of these authenticated POMs. This approach allows users to authenticate the two POMs used for image reconstruction without visual observation of the reference images. It also allows user to friendly access and readout with mobile devices.
Zhu, Yenan; Hsieh, Yee-Hsee; Dhingra, Rishi R.; Dick, Thomas E.; Jacono, Frank J.; Galán, Roberto F.
2013-02-01
Interactions between oscillators can be investigated with standard tools of time series analysis. However, these methods are insensitive to the directionality of the coupling, i.e., the asymmetry of the interactions. An elegant alternative was proposed by Rosenblum and collaborators [M. G. Rosenblum, L. Cimponeriu, A. Bezerianos, A. Patzak, and R. Mrowka, Phys. Rev. EPLEEE81063-651X10.1103/PhysRevE.65.041909 65, 041909 (2002); M. G. Rosenblum and A. S. Pikovsky, Phys. Rev. EPLEEE81063-651X10.1103/PhysRevE.64.045202 64, 045202 (2001)] which consists in fitting the empirical phases to a generic model of two weakly coupled phase oscillators. This allows one to obtain the interaction functions defining the coupling and its directionality. A limitation of this approach is that a solution always exists in the least-squares sense, even in the absence of coupling. To preclude spurious results, we propose a three-step protocol: (1) Determine if a statistical dependency exists in the data by evaluating the mutual information of the phases; (2) if so, compute the interaction functions of the oscillators; and (3) validate the empirical oscillator model by comparing the joint probability of the phases obtained from simulating the model with that of the empirical phases. We apply this protocol to a model of two coupled Stuart-Landau oscillators and show that it reliably detects genuine coupling. We also apply this protocol to investigate cardiorespiratory coupling in anesthetized rats. We observe reciprocal coupling between respiration and heartbeat and that the influence of respiration on the heartbeat is generally much stronger than vice versa. In addition, we find that the vagus nerve mediates coupling in both directions.
Quantifying Complexity in Quantum Phase Transitions via Mutual Information Complex Networks.
Valdez, Marc Andrew; Jaschke, Daniel; Vargas, David L; Carr, Lincoln D
2017-12-01
We quantify the emergent complexity of quantum states near quantum critical points on regular 1D lattices, via complex network measures based on quantum mutual information as the adjacency matrix, in direct analogy to quantifying the complexity of electroencephalogram or functional magnetic resonance imaging measurements of the brain. Using matrix product state methods, we show that network density, clustering, disparity, and Pearson's correlation obtain the critical point for both quantum Ising and Bose-Hubbard models to a high degree of accuracy in finite-size scaling for three classes of quantum phase transitions, Z_{2}, mean field superfluid to Mott insulator, and a Berzinskii-Kosterlitz-Thouless crossover.
Quantifying Complexity in Quantum Phase Transitions via Mutual Information Complex Networks
Valdez, Marc Andrew; Jaschke, Daniel; Vargas, David L.; Carr, Lincoln D.
2017-12-01
We quantify the emergent complexity of quantum states near quantum critical points on regular 1D lattices, via complex network measures based on quantum mutual information as the adjacency matrix, in direct analogy to quantifying the complexity of electroencephalogram or functional magnetic resonance imaging measurements of the brain. Using matrix product state methods, we show that network density, clustering, disparity, and Pearson's correlation obtain the critical point for both quantum Ising and Bose-Hubbard models to a high degree of accuracy in finite-size scaling for three classes of quantum phase transitions, Z2, mean field superfluid to Mott insulator, and a Berzinskii-Kosterlitz-Thouless crossover.
International Nuclear Information System (INIS)
Mishchenko, Yuriy
2004-01-01
MISHCHENKO, YURIY. Applications of Canonical Transformations and Nontrivial Vacuum Solutions to flavor mixing and critical phenomena in Quantum Field Theory. (Under the direction of Chueng-Ryong Ji.) In this dissertation we consider two recent applications of Bogoliubov Transformation to the phenomenology of quantum mixing and the theory of critical phenomena. In recent years quantum mixing got in the focus of the searches for New Physics due to its unparalleled sensitivity to SM parameters and indications of neutrino mixing. It was recently suggested that Bogoliubov Transformation may be important in proper definition of the flavor states that otherwise results in problems in perturbative treatment. As first part of this dissertation we investigate this conjecture and develop a complete formulation of such a mixing field theory involving introduction of general formalism, analysis of space-time conversion and phenomenological implications. As second part of this dissertati
Energy Technology Data Exchange (ETDEWEB)
Mishchenko, Yuriy [North Carolina State Univ., Raleigh, NC (United States)
2004-12-01
MISHCHENKO, YURIY. Applications of Canonical Transformations and Nontrivial Vacuum Solutions to flavor mixing and critical phenomena in Quantum Field Theory. (Under the direction of Chueng-Ryong Ji.) In this dissertation we consider two recent applications of Bogoliubov Transformation to the phenomenology of quantum mixing and the theory of critical phenomena. In recent years quantum mixing got in the focus of the searches for New Physics due to its unparalleled sensitivity to SM parameters and indications of neutrino mixing. It was recently suggested that Bogoliubov Transformation may be important in proper definition of the flavor states that otherwise results in problems in perturbative treatment. As first part of this dissertation we investigate this conjecture and develop a complete formulation of such a mixing field theory involving introduction of general formalism, analysis of space-time conversion and phenomenological implications. As second part of this dissertati
Energy Technology Data Exchange (ETDEWEB)
Grattidge, W.; Westbrook, J.; McCarthy, J.; Northrup, C. Jr.; Rumble, J. Jr.
1986-01-01
This report documents the initial phases of the Materials Information for Science and Technology (MIST) project jointly supported by the Department of Energy and the National Bureau of Standards. The purpose of MIST is to demonstrate the power and utility of computer access to materials property data. The initial goals include: to exercise the concept of a computer network of materials databases and to build a demonstration of such a system suitable for use as the core of operational systems in the future. Phases I and II are described in detail herein. In addition, a discussion is given of the expected usage of the system. The primary MIST prototype project is running on an IBM 3084 under STS at the Stanford University's Information Technology Services (ITS). Users can access the Stanford system via ARPANET, TELENET, and TYMNET, as well as via commercial telephone lines. For fastest response time and use of the full screen PRISM interface, direct connection using a 2400 baud modem with the MNP error-correcting protocol over standard telephone lines gives the best results - though slower speed connections and a line-oriented interface are also available. This report gives detailed plans regarding the properties to be enterend and the materials to be entered into the system.
Brown, Nathaniel James Swanton
While there is consensus that conceptual change is surprisingly difficult, many competing theories of conceptual change co-exist in the literature. This dissertation argues that this discord is partly the result of an inadequate account of the unwritten rules of human social interaction that underlie the field's preferred methodology---semi-structured interviewing. To better understand the contributions of interaction during explanations, I analyze eight undergraduate general chemistry students as they attempt to explain to various people, for various reasons, why phenomena involving chemical phase equilibrium occur. Using the methods of interaction analysis, I characterize the unwritten, but systematic, rules that these participants follow as they explain. The result is a description of the contributions of interaction to explaining. Each step in each explanation is a jointly performed expression of a subject-predicate relation, an interactive accomplishment I call an information performance (in-form, for short). Unlike clauses, in-forms need not have a coherent grammatical structure. Unlike speaker turns, in-forms have the clear function of expressing information. Unlike both clauses and speaker turns, in-forms are a co-construction, jointly performed by both the primary speaker and the other interlocutor. The other interlocutor strongly affects the form and content of each explanation by giving or withholding feedback at the end of each in-form, moments I call feedback-relevant places. While in-forms are the bricks out of which the explanation is constructed, they are secured by a series of inferential links I call an illative sequence. Illative sequences are forward-searching, starting with a remembered fact or observation and following a chain of inferences in the hope it leads to the target phenomenon. The participants treat an explanation as a success if the illative sequence generates an in-form that describes the phenomenon. If the illative sequence does
Xu, Jingjiang; Song, Shaozhen; Li, Yuandong; Wang, Ruikang K
2017-12-19
Optical coherence tomography angiography (OCTA) is increasingly becoming a popular inspection tool for biomedical imaging applications. By exploring the amplitude, phase and complex information available in OCT signals, numerous algorithms have been proposed that contrast functional vessel networks within microcirculatory tissue beds. However, it is not clear which algorithm delivers optimal imaging performance. Here, we investigate systematically how amplitude and phase information have an impact on the OCTA imaging performance, to establish the relationship of amplitude and phase stability with OCT signal-to-noise ratio (SNR), time interval and particle dynamics. With either repeated A-scan or repeated B-scan imaging protocols, the amplitude noise increases with the increase of OCT SNR; however, the phase noise does the opposite, i.e. it increases with the decrease of OCT SNR. Coupled with experimental measurements, we utilize a simple Monte Carlo (MC) model to simulate the performance of amplitude-, phase- and complex-based algorithms for OCTA imaging, the results of which suggest that complex-based algorithms deliver the best performance when the phase noise is algorithm delivers better performance than either the amplitude- or phase-based algorithms for both the repeated A-scan and the B-scan imaging protocols, which agrees well with the conclusion drawn from the MC simulations.
Quantitative metrics for evaluating the phased roll-out of clinical information systems.
Wong, David; Wu, Nicolas; Watkinson, Peter
2017-09-01
We introduce a novel quantitative approach for evaluating the order of roll-out during phased introduction of clinical information systems. Such roll-outs are associated with unavoidable risk due to patients transferring between clinical areas using both the old and new systems. We proposed a simple graphical model of patient flow through a hospital. Using a simple instance of the model, we showed how a roll-out order can be generated by minimising the flow of patients from the new system to the old system. The model was applied to admission and discharge data acquired from 37,080 patient journeys at the Churchill Hospital, Oxford between April 2013 and April 2014. The resulting order was evaluated empirically and produced acceptable orders. The development of data-driven approaches to clinical Information system roll-out provides insights that may not necessarily be ascertained through clinical judgment alone. Such methods could make a significant contribution to the smooth running of an organisation during the roll-out of a potentially disruptive technology. Unlike previous approaches, which are based on clinical opinion, the approach described here quantitatively assesses the appropriateness of competing roll-out strategies. The data-driven approach was shown to produce strategies that matched clinical intuition and provides a flexible framework that may be used to plan and monitor Clinical Information System roll-out. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
A method to extract quantitative information in analyzer-based x-ray phase contrast imaging
International Nuclear Information System (INIS)
Pagot, E.; Cloetens, P.; Fiedler, S.; Bravin, A.; Coan, P.; Baruchel, J.; Haertwig, J.; Thomlinson, W.
2003-01-01
Analyzer-based imaging is a powerful phase-sensitive technique that generates improved contrast compared to standard absorption radiography. Combining numerically two images taken on either side at ±1/2 of the full width at half-maximum (FWHM) of the rocking curve provides images of 'pure refraction' and of 'apparent absorption'. In this study, a similar approach is made by combining symmetrical images with respect to the peak of the analyzer rocking curve but at general positions, ±α·FWHM. These two approaches do not consider the ultrasmall angle scattering produced by the object independently, which can lead to inconsistent results. An accurate way to separately retrieve the quantitative information intrinsic to the object is proposed. It is based on a statistical analysis of the local rocking curve, and allows one to overcome the problems encountered using the previous approaches
Topologically nontrivial quantum layers
International Nuclear Information System (INIS)
Carron, G.; Exner, P.; Krejcirik, D.
2004-01-01
Given a complete noncompact surface Σ embedded in R 3 , we consider the Dirichlet Laplacian in the layer Ω that is defined as a tubular neighborhood of constant width about Σ. Using an intrinsic approach to the geometry of Ω, we generalize the spectral results of the original paper by Duclos et al. [Commun. Math. Phys. 223, 13 (2001)] to the situation when Σ does not possess poles. This enables us to consider topologically more complicated layers and state new spectral results. In particular, we are interested in layers built over surfaces with handles or several cylindrically symmetric ends. We also discuss more general regions obtained by compact deformations of certain Ω
Stanislaus, Romesh; Carey, Mark; Deus, Helena F; Coombes, Kevin; Hennessy, Bryan T; Mills, Gordon B; Almeida, Jonas S
2008-12-22
Reverse Phase Protein Arrays (RPPA) are convenient assay platforms to investigate the presence of biomarkers in tissue lysates. As with other high-throughput technologies, substantial amounts of analytical data are generated. Over 1,000 samples may be printed on a single nitrocellulose slide. Up to 100 different proteins may be assessed using immunoperoxidase or immunoflorescence techniques in order to determine relative amounts of protein expression in the samples of interest. In this report an RPPA Information Management System (RIMS) is described and made available with open source software. In order to implement the proposed system, we propose a metadata format known as reverse phase protein array markup language (RPPAML). RPPAML would enable researchers to describe, document and disseminate RPPA data. The complexity of the data structure needed to describe the results and the graphic tools necessary to visualize them require a software deployment distributed between a client and a server application. This was achieved without sacrificing interoperability between individual deployments through the use of an open source semantic database, S3DB. This data service backbone is available to multiple client side applications that can also access other server side deployments. The RIMS platform was designed to interoperate with other data analysis and data visualization tools such as Cytoscape. The proposed RPPAML data format hopes to standardize RPPA data. Standardization of data would result in diverse client applications being able to operate on the same set of data. Additionally, having data in a standard format would enable data dissemination and data analysis.
RPPAML/RIMS: A metadata format and an information management system for reverse phase protein arrays
Directory of Open Access Journals (Sweden)
Hennessy Bryan T
2008-12-01
Full Text Available Abstract Background Reverse Phase Protein Arrays (RPPA are convenient assay platforms to investigate the presence of biomarkers in tissue lysates. As with other high-throughput technologies, substantial amounts of analytical data are generated. Over 1000 samples may be printed on a single nitrocellulose slide. Up to 100 different proteins may be assessed using immunoperoxidase or immunoflorescence techniques in order to determine relative amounts of protein expression in the samples of interest. Results In this report an RPPA Information Management System (RIMS is described and made available with open source software. In order to implement the proposed system, we propose a metadata format known as reverse phase protein array markup language (RPPAML. RPPAML would enable researchers to describe, document and disseminate RPPA data. The complexity of the data structure needed to describe the results and the graphic tools necessary to visualize them require a software deployment distributed between a client and a server application. This was achieved without sacrificing interoperability between individual deployments through the use of an open source semantic database, S3DB. This data service backbone is available to multiple client side applications that can also access other server side deployments. The RIMS platform was designed to interoperate with other data analysis and data visualization tools such as Cytoscape. Conclusion The proposed RPPAML data format hopes to standardize RPPA data. Standardization of data would result in diverse client applications being able to operate on the same set of data. Additionally, having data in a standard format would enable data dissemination and data analysis.
Real-Time Traffic Information for Emergency Evacuation Operations: Phase A Final Report
Energy Technology Data Exchange (ETDEWEB)
Franzese, Oscar [ORNL; Zhang, Li [Mississippi State University (MSU); Mahmoud, Anas M. [Mississippi State University (MSU); Lascurain, Mary Beth [ORNL; Wen, Yi [Mississippi State University (MSU)
2010-05-01
There are many instances in which it is possible to plan ahead for an emergency evacuation (e.g., an explosion at a chemical processing facility). For those cases, if an accident (or an attack) were to happen, then the best evacuation plan for the prevailing network and weather conditions would be deployed. In other cases (e.g., the derailment of a train transporting hazardous materials), there may not be any previously developed plan to be implemented and decisions must be made ad-hoc on how to proceed with an emergency evacuation. In both situations, the availability of real-time traffic information plays a critical role in the management of the evacuation operations. To improve public safety during a vehicular emergency evacuation it is necessary to detect losses of road capacity (due to incidents, for example) as early as possible. Once these bottlenecks are identified, re-routing strategies must be determined in real-time and deployed in the field to help dissipate the congestion and increase the efficiency of the evacuation. Due to cost constraints, only large urban areas have traffic sensor deployments that permit access to some sort of real-time traffic information; any evacuation taking place in any other areas of the country would have to proceed without real-time traffic information. The latter was the focus of this SERRI/DHS (Southeast Region Research Initiative/Department of Homeland Security) sponsored project. That is, the main objective on the project was to improve the operations during a vehicular emergency evacuation anywhere by using newly developed real-time traffic-information-gathering technologies to assess traffic conditions and therefore to potentially detect incidents on the main evacuation routes. Phase A of the project consisted in the development and testing of a prototype system composed of sensors that are engineered in such a way that they can be rapidly deployed in the field where and when they are needed. Each one of these sensors
International Nuclear Information System (INIS)
Weissenbach, Kurt; Schillinger, Wolfgang; Weidemann, Rainer
2016-01-01
The R and D project INOVUM of the Ministry for the Environment, Climate and Energy Baden-Wuerttemberg relies on a wide cooperation with partners from government, science and industry to jointly develop governmental environmental information systems. In the focus of this project phase were, e.g. a revision of the framework concept for the Environmental Information System Baden-Wuerttemberg, service-based applications, the development of environmental portals, mobile applications and map services.
Interventions for supporting informal caregivers of patients in the terminal phase of a disease.
Candy, Bridget; Jones, Louise; Drake, Robyn; Leurent, Baptiste; King, Michael
2011-06-15
Patients in the terminal phase of a disease may have complex needs. It is often family and friends who play a central role in providing support, despite health professional input and regardless of whether the patient is at home or elsewhere. Such informal caring may involve considerable physical, psychological, and economic stresses. A range of supportive programmes for caregivers is being developed including psychological support and practical assistance. To assess the effects of supportive interventions that aim to improve the psychological and physical health of informal caregivers of patients in the terminal phase of their illness. We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2 2010); MEDLINE (1950 to May 2010); EMBASE (1980 to May 2010); PsycINFO (1872 to May 2010); CINAHL (1937 to May 2010); National Health Service Research Register (2000 to November 2008) and Dissertation Abstracts (1716 to May 2010). We searched the reference lists of relevant studies; contacted experts; and handsearched journals. Randomised controlled trials (RCTs) of interventions to support adults who were caring for a friend or relative with a disease in the terminal phase. Interventions could include practical and emotional support and/or the facilitation of coping skills. Interventions could support caregivers indirectly via patient care. Two authors independently screened citations against the selection criteria. Data were extracted by one author and checked by another. This included extraction of any adverse effects. Risk of bias assessment was undertaken by two authors. We contacted trial authors to obtain missing information. Trial data were combined, where appropriate, on the review's primary outcomes. We included eleven RCTs involving 1836 caregiver participants. Nine interventions were delivered directly to the caregiver. Seven of these provided support in the caring role, another involved a family life review, and one
International Nuclear Information System (INIS)
Har-Shemesh, Omri; Quax, Rick; Hoekstra, Alfons G; Sloot, Peter M A
2016-01-01
The Fisher–Rao metric from information geometry is related to phase transition phenomena in classical statistical mechanics. Several studies propose to extend the use of information geometry to study more general phase transitions in complex systems. However, it is unclear whether the Fisher–Rao metric does indeed detect these more general transitions, especially in the absence of a statistical model. In this paper we study the transitions between patterns in the Gray-Scott reaction–diffusion model using Fisher information. We describe the system by a probability density function that represents the size distribution of blobs in the patterns and compute its Fisher information with respect to changing the two rate parameters of the underlying model. We estimate the distribution non-parametrically so that we do not assume any statistical model. The resulting Fisher map can be interpreted as a phase-map of the different patterns. Lines with high Fisher information can be considered as boundaries between regions of parameter space where patterns with similar characteristics appear. These lines of high Fisher information can be interpreted as phase transitions between complex patterns. (paper: disordered systems, classical and quantum)
A new method for information retrieval in two-dimensional grating-based X-ray phase contrast imaging
International Nuclear Information System (INIS)
Wang Zhi-Li; Gao Kun; Chen Jian; Ge Xin; Tian Yang-Chao; Wu Zi-Yu; Zhu Pei-Ping
2012-01-01
Grating-based X-ray phase contrast imaging has been demonstrated to be an extremely powerful phase-sensitive imaging technique. By using two-dimensional (2D) gratings, the observable contrast is extended to two refraction directions. Recently, we have developed a novel reverse-projection (RP) method, which is capable of retrieving the object information efficiently with one-dimensional (1D) grating-based phase contrast imaging. In this contribution, we present its extension to the 2D grating-based X-ray phase contrast imaging, named the two-dimensional reverse-projection (2D-RP) method, for information retrieval. The method takes into account the nonlinear contributions of two refraction directions and allows the retrieval of the absorption, the horizontal and the vertical refraction images. The obtained information can be used for the reconstruction of the three-dimensional phase gradient field, and for an improved phase map retrieval and reconstruction. Numerical experiments are carried out, and the results confirm the validity of the 2D-RP method
Tahara, Tatsuki; Mori, Ryota; Kikunaga, Shuhei; Arai, Yasuhiko; Takaki, Yasuhiro
2015-06-15
Dual-wavelength phase-shifting digital holography that selectively extracts wavelength information from five wavelength-multiplexed holograms is presented. Specific phase shifts for respective wavelengths are introduced to remove the crosstalk components and extract only the object wave at the desired wavelength from the holograms. Object waves in multiple wavelengths are selectively extracted by utilizing 2π ambiguity and the subtraction procedures based on phase-shifting interferometry. Numerical results show the validity of the proposed technique. The proposed technique is also experimentally demonstrated.
Energy Technology Data Exchange (ETDEWEB)
Weissenbach, Kurt [Ministerium fuer Umwelt, Klima und Energiewirtschaft Baden-Wuerttemberg, Stuttgart (Germany); Schillinger, Wolfgang [Landesanstalt fuer Umwelt, Messungen und Naturschutz Baden-Wuerttemberg (LUBW), Karlsruhe (Germany); Weidemann, Rainer (ed.) [Karlsruher Institut fuer Technologie (Germany). Inst. fuer Angewandte Informatik
2016-07-01
The R and D project INOVUM of the Ministry for the Environment, Climate and Energy Baden-Wuerttemberg relies on a wide cooperation with partners from government, science and industry to jointly develop governmental environmental information systems. In the focus of this project phase were, e.g. a revision of the framework concept for the Environmental Information System Baden-Wuerttemberg, service-based applications, the development of environmental portals, mobile applications and map services.
Wu, Z.; Gao, K.; Wang, Z. L.; Shao, Q. G.; Hu, R. F.; Wei, C. X.; Zan, G. B.; Wali, F.; Luo, R. H.; Zhu, P. P.; Tian, Y. C.
2017-06-01
In X-ray grating-based phase contrast imaging, information retrieval is necessary for quantitative research, especially for phase tomography. However, numerous and repetitive processes have to be performed for tomographic reconstruction. In this paper, we report a novel information retrieval method, which enables retrieving phase and absorption information by means of a linear combination of two mutually conjugate images. Thanks to the distributive law of the multiplication as well as the commutative law and associative law of the addition, the information retrieval can be performed after tomographic reconstruction, thus simplifying the information retrieval procedure dramatically. The theoretical model of this method is established in both parallel beam geometry for Talbot interferometer and fan beam geometry for Talbot-Lau interferometer. Numerical experiments are also performed to confirm the feasibility and validity of the proposed method. In addition, we discuss its possibility in cone beam geometry and its advantages compared with other methods. Moreover, this method can also be employed in other differential phase contrast imaging methods, such as diffraction enhanced imaging, non-interferometric imaging, and edge illumination.
Beernaert, Kim; Haverbeke, Chloë; Van Belle, Simon; Deliens, Luc; Cohen, Joachim
2018-01-01
We assessed information provision and information needs about illness course, treatments, palliative care and euthanasia in cancer patients. Cancer patients consulting a university hospital (N=620) filled out a questionnaire. Their cancer related data were collected through the treating oncologist. This study is performed in Belgium, where "palliative care for all" is a patient's right embedded in the law and euthanasia is possible under certain conditions. Around 80% received information about their illness course and treatments. Ten percent received information about palliative care and euthanasia. Most information about palliative care and euthanasia was given when the patient had a life expectancy of less than six months. However, a quarter of those in earlier phases in their illness trajectory, particularly those who experienced high pain, fatigue or nausea requested more information on these topics. Many patients want more information about palliative care and euthanasia than what is currently provided, also those in an earlier than terminal phase of their disease. Healthcare professionals should be more responsive, already from diagnosis, to the information needs about palliative care and possible end-of-life decisions. This should be patient-tailored, as some patients want more and some patients want less information. Copyright © 2017 Elsevier B.V. All rights reserved.
Coddington, O. M.; Vukicevic, T.; Schmidt, K. S.; Platnick, S.
2017-08-01
We rigorously quantify the probability of liquid or ice thermodynamic phase using only shortwave spectral channels specific to the National Aeronautics and Space Administration's Moderate Resolution Imaging Spectroradiometer, Visible Infrared Imaging Radiometer Suite, and the notional future Plankton, Aerosol, Cloud, ocean Ecosystem imager. The results show that two shortwave-infrared channels (2135 and 2250 nm) provide more information on cloud thermodynamic phase than either channel alone; in one case, the probability of ice phase retrieval increases from 65 to 82% by combining 2135 and 2250 nm channels. The analysis is performed with a nonlinear statistical estimation approach, the GEneralized Nonlinear Retrieval Analysis (GENRA). The GENRA technique has previously been used to quantify the retrieval of cloud optical properties from passive shortwave observations, for an assumed thermodynamic phase. Here we present the methodology needed to extend the utility of GENRA to a binary thermodynamic phase space (i.e., liquid or ice). We apply formal information content metrics to quantify our results; two of these (mutual and conditional information) have not previously been used in the field of cloud studies.
Tzvi, Elinor; Bauhaus, Leon J; Kessler, Till U; Liebrand, Matthias; Wöstmann, Malte; Krämer, Ulrike M
2018-03-01
Cross-frequency coupling is suggested to serve transfer of information between wide-spread neuronal assemblies and has been shown to underlie many cognitive functions including learning and memory. In previous work, we found that alpha (8-13 Hz) - gamma (30-48 Hz) phase amplitude coupling (αγPAC) is decreased during sequence learning in bilateral frontal cortex and right parietal cortex. We interpreted this to reflect decreased demands for visuo-motor mapping once the sequence has been encoded. In the present study, we put this hypothesis to the test by adding a "simple" condition to the standard serial reaction time task (SRTT) with minimal needs for visuo-motor mapping. The standard SRTT in our paradigm entailed a perceptual sequence allowing for implicit learning of a sequence of colors with randomly assigned motor responses. Sequence learning in this case was thus not associated with reduced demands for visuo-motor mapping. Analysis of oscillatory power revealed a learning-related alpha decrease pointing to a stronger recruitment of occipito-parietal areas when encoding the perceptual sequence. Replicating our previous findings but in contrast to our hypothesis, αγPAC was decreased in sequence compared to random trials over right frontal and parietal cortex. It also tended to be smaller compared to trials requiring a simple motor sequence. We additionally analyzed αγPAC in resting-state data of a separate cohort. PAC in electrodes over right parietal cortex was significantly stronger compared to sequence trials and tended to be higher compared to simple and random trials of the SRTT data. We suggest that αγPAC in right parietal cortex reflects a "default-mode" brain state, which gets perturbed to allow for encoding of visual regularities into memory. Copyright © 2018 Elsevier Inc. All rights reserved.
International Nuclear Information System (INIS)
Yan Changhui
2001-01-01
Centralized Data Processing and Safety Panel (KIT/KPS) of Qinshan Phase-II power project is described, and the necessity and engineering scheme is presented of integrated information management and automatic control that would achieve in power plant according to the technology scheme and technology trait of KIT/KPS
SmartTopo Intelligent Real-Time Topographic Information Collection System, Phase II
National Aeronautics and Space Administration — The SmartTopo SBIR phase I program resulted in the creation of the first technology designed to provide robotic vehicles with the ability to "learn and remember" the...
Hybrid Reactor Simulation and 3-D Information Display of BWR Out-of-Phase Oscillation
International Nuclear Information System (INIS)
Edwards, Robert; Huang, Zhengyu
2001-01-01
The real-time hybrid reactor simulation (HRS) capability of the Penn State TRIGA reactor has been expanded for boiling water reactor (BWR) out-of-phase behavior. During BWR out-of-phase oscillation half of the core can significantly oscillate out of phase with the other half, while the average power reported by the neutronic instrumentation may show a much lower amplitude for the oscillations. A description of the new HRS is given; three computers are employed to handle all the computations required, including real-time data processing and graph generation. BWR out-of-phase oscillation was successfully simulated. By adjusting the reactivity feedback gains from boiling channels to the TRIGA reactor and to the first harmonic mode power simulation, limit cycle can be generated with both reactor power and the simulated first harmonic power. A 3-D display of spatial power distributions of fundamental mode, first harmonic, and total powers over the reactor cross section is shown
Crystallographic information of intermediate phases in binary Mg–X (X=Sn, Y, Sc, Ag alloys
Directory of Open Access Journals (Sweden)
Dongyan Liu
2015-09-01
Full Text Available The compositions and structures of thermodynamically stable or metastable precipitations in binary Mg-X (X=Sn, Y, Sc, Ag alloys are predicted using ab-initio evolutionary algorithm. The geometry optimizations of the predicted intermetallic compounds are carried out in the framework of density functional theory (DFT [1]. A complete list of the optimized crystallographic information (in cif format of the predicted intermetallic phases is presented here. The data is related to “Predictions on the compositions, structures, and mechanical properties of intermediate phases in binary Mg–X (X=Sn, Y, Sc, Ag alloys” by Liu et al. [2].
International Nuclear Information System (INIS)
Kazantsev, Victor; Pimashkin, Alexey
2007-01-01
We propose two-layer architecture of associative memory oscillatory network with directional interlayer connectivity. The network is capable to store information in the form of phase-locked (in-phase and antiphase) oscillatory patterns. The first (input) layer takes an input pattern to be recognized and their units are unidirectionally connected with all units of the second (control) layer. The connection strengths are weighted using the Hebbian rule. The output (retrieved) patterns appear as forced-phase locked states of the control layer. The conditions are found and analytically expressed for pattern retrieval in response on incoming stimulus. It is shown that the system is capable to recover patterns with a certain level of distortions or noises in their profiles. The architecture is implemented with the Kuramoto phase model and using synaptically coupled neural oscillators with spikes. It is found that the spiking model is capable to retrieve patterns using the spiking phase that translates memorized patterns into the spiking phase shifts at different time scales
Fan, Desheng; Meng, Xiangfeng; Wang, Yurong; Yang, Xiulun; Pan, Xuemei; Peng, Xiang; He, Wenqi; Dong, Guoyan; Chen, Hongyi
2015-04-10
A multiple-image authentication method with a cascaded multilevel architecture in the Fresnel domain is proposed, in which a synthetic encoded complex amplitude is first fabricated, and its real amplitude component is generated by iterative amplitude encoding, random sampling, and space multiplexing for the low-level certification images, while the phase component of the synthetic encoded complex amplitude is constructed by iterative phase information encoding and multiplexing for the high-level certification images. Then the synthetic encoded complex amplitude is iteratively encoded into two phase-type ciphertexts located in two different transform planes. During high-level authentication, when the two phase-type ciphertexts and the high-level decryption key are presented to the system and then the Fresnel transform is carried out, a meaningful image with good quality and a high correlation coefficient with the original certification image can be recovered in the output plane. Similar to the procedure of high-level authentication, in the case of low-level authentication with the aid of a low-level decryption key, no significant or meaningful information is retrieved, but it can result in a remarkable peak output in the nonlinear correlation coefficient of the output image and the corresponding original certification image. Therefore, the method realizes different levels of accessibility to the original certification image for different authority levels with the same cascaded multilevel architecture.
Bijster, R.J.F.; Vreugd, J. de; Sadeghian Marnani, H.
2014-01-01
In photo-thermal actuation, heat is added locally to a micro-cantilever by means of a laser. A fraction of the irradiation is absorbed, yielding thermal stresses and deformations in the structure. Harmonic modulation of the laser power causes the cantilever to oscillate. Moreover, a phase lag is
Multi-phase simultaneous segmentation of tumor in lung 4D-CT data with context information.
Directory of Open Access Journals (Sweden)
Zhengwen Shen
Full Text Available Lung 4D computed tomography (4D-CT plays an important role in high-precision radiotherapy because it characterizes respiratory motion, which is crucial for accurate target definition. However, the manual segmentation of a lung tumor is a heavy workload for doctors because of the large number of lung 4D-CT data slices. Meanwhile, tumor segmentation is still a notoriously challenging problem in computer-aided diagnosis. In this paper, we propose a new method based on an improved graph cut algorithm with context information constraint to find a convenient and robust approach of lung 4D-CT tumor segmentation. We combine all phases of the lung 4D-CT into a global graph, and construct a global energy function accordingly. The sub-graph is first constructed for each phase. A context cost term is enforced to achieve segmentation results in every phase by adding a context constraint between neighboring phases. A global energy function is finally constructed by combining all cost terms. The optimization is achieved by solving a max-flow/min-cut problem, which leads to simultaneous and robust segmentation of the tumor in all the lung 4D-CT phases. The effectiveness of our approach is validated through experiments on 10 different lung 4D-CT cases. The comparison with the graph cut without context constraint, the level set method and the graph cut with star shape prior demonstrates that the proposed method obtains more accurate and robust segmentation results.
Patient versus informant reported quality of life in the earliest phases of Alzheimer's disease
DEFF Research Database (Denmark)
Vogel, Asmus; Mortensen, Erik Lykke; Hasselbalch, Steen G
2006-01-01
The study investigated if patient and informant reported Quality of Life (QoL) differed in early Alzheimer's disease (AD). In addition, we examined whether anosognosia had an impact on the agreement between patient and informant ratings of QoL and whether anosognosia, dementia severity, depression...
Patient versus informant reported quality of life in the earliest phases of Alzheimer's disease
DEFF Research Database (Denmark)
Vogel, Asmus; Mortensen, Erik Lykke; Hasselbalch, Steen G
2006-01-01
The study investigated if patient and informant reported Quality of Life (QoL) differed in early Alzheimer's disease (AD). In addition, we examined whether anosognosia had an impact on the agreement between patient and informant ratings of QoL and whether anosognosia, dementia severity, depressio...
RPPAML/RIMS: A metadata format and an information management system for reverse phase protein arrays
Stanislaus, Romesh; Carey, Mark; Deus, Helena F; Coombes, Kevin; Hennessy, Bryan T; Mills, Gordon B; Almeida, Jonas S
2008-01-01
Abstract Background Reverse Phase Protein Arrays (RPPA) are convenient assay platforms to investigate the presence of biomarkers in tissue lysates. As with other high-throughput technologies, substantial amounts of analytical data are generated. Over 1000 samples may be printed on a single nitrocellulose slide. Up to 100 different proteins may be assessed using immunoperoxidase or immunoflorescence techniques in order to determine relative amounts of protein expression in the samples of inter...
International Nuclear Information System (INIS)
Chen, C.-L.; Thomson, R.C.
2010-01-01
Multicomponent Al-Si based casting alloys are used for a variety of engineering applications, including for example, piston alloys. Properties include good castability, high strength, light weight, good wear resistance and low thermal expansion. In order for such alloys to continue operation to increasingly higher temperatures, alloy element modifications are continually being made to further enhance the properties. Improved mechanical and physical properties are strongly dependent upon the morphologies, type and distribution of the second phases, which are in turn a function of alloy composition and cooling rate. The presence of additional elements in the Al-Si alloy system allows many complex intermetallic phases to form, which make characterisation non-trivial. These include, for example, CuAl 2 , Al 3 Ni 2 , Al 7 Cu 4 Ni, Al 9 FeNi and Al 5 Cu 2 Mg 8 Si 6 phases, all of which may have some solubility for additional elements. Identification is often non-trivial due to the fact that some of the phases have either similar crystal structures or only subtle changes in their chemistries. A combination of electron backscatter diffraction (EBSD) and energy dispersive X-ray analysis (EDX) has therefore been used for the identification of the various phases. This paper will present comparisons of phase identification methodologies using EBSD alone, and in combination with chemical information, either directly or through post processing.
Wiki-Based Data and Information Integration (WikiDI2) System, Phase I
National Aeronautics and Space Administration — The proposed innovation is: A data and information integration (DI2) system built from the methods and tools used to create Wiki websites. Wiki (Hawaiian for...
Intelligent Information Processing for Enhanced Safety in the NAS, Phase I
National Aeronautics and Space Administration — We propose a system that focuses on how improved information flow between agents acting in a flight deck environment can improve safety performance. Agents are...
Dorota LESZCZYŃSKA; Laurence SAGLIETTO
2014-01-01
If perception is a concept which is necessarily intuitive in the analysis of transformations in information systems, it is not to be taken into account at its fair value in existing theoretical models. These models are mainly interested in
1997-06-01
The Geographic Information System-Transportation (GIS-T) ISTEA Management Systems Server Net Prototype Pooled Fund Study represents the first national cooperative effort in the transportation industry to address the management and monitoring systems ...
Goranson, H. T.
1986-01-01
The Technical and Management Information System (TMIS) must employ on enlightened approach to its object structure, but basic issues in conceptual structuring remain to be resolved. Sirius outlines the necessary agenda and reports on progress toward solutions.
International Nuclear Information System (INIS)
Niemiec, W.
1985-01-01
A constitutive mathematical model of distributed parameters of multicomponent chemical processes in gas, fluid and solid phase is utilized to the realization of phenomenal distributed parameter control of these processes. Original systems of partial differential constitutive state equations, in the following derivative forms /I/, /II/ and /III/ are solved in this paper from the point of view of information for phenomenal distributed parameter control of considered processes. Obtained in this way for multicomponent chemical processes in gas, fluid and solid phase: -dynamical working space-time characteristics/analytical solutions in working space-time of chemical reactors/, -dynamical phenomenal Green functions as working space-time transfer functions, -statical working space characteristics /analytical solutions in working space of chemical reactors/, -statical phenomenal Green functions as working space transfer functions, are applied, as information for realization of constitutive distributed parameter control of mass, energy and momentum aspects of above processes. Two cases are considered by existence of: A/sup o/ - initial conditions, B/sup o/ - initial and boundary conditions, for multicomponent chemical processes in gas, fluid and solid phase
Sinharay, Arijit; Rakshit, Raj; Khasnobish, Anwesha; Chakravarty, Tapas; Ghosh, Deb; Pal, Arpan
2017-08-11
Pulmonary ailments are conventionally diagnosed by spirometry. The complex forceful breathing maneuver as well as the extreme cost of spirometry renders it unsuitable in many situations. This work is aimed to facilitate an emerging direction of tidal breathing-based pulmonary evaluation by designing a novel, equitable, precise and portable device for acquisition and analysis of directional tidal breathing patterns, in real time. The proposed system primarily uses an in-house designed blow pipe, 40-kHz air-coupled ultrasound transreceivers, and a radio frequency (RF) phase-gain integrated circuit (IC). Moreover, in order to achieve high sensitivity in a cost-effective design philosophy, we have exploited the phase measurement technique, instead of selecting the contemporary time-of-flight (TOF) measurement; since application of the TOF principle in tidal breathing assessments requires sub-micro to nanosecond time resolution. This approach, which depends on accurate phase measurement, contributed to enhanced sensitivity using a simple electronics design. The developed system has been calibrated using a standard 3-L calibration syringe. The parameters of this system are validated against a standard spirometer, with maximum percentage error below 16%. Further, the extracted respiratory parameters related to tidal breathing have been found to be comparable with relevant prior works. The error in detecting respiration rate only is 3.9% compared to manual evaluation. These encouraging insights reveal the definite potential of our tidal breathing pattern (TBP) prototype for measuring tidal breathing parameters in order to extend the reach of affordable healthcare in rural regions and developing areas.
Review of power sources for Alaska DOT & PF road weather information systems (RWIS) : phase I.
2014-06-01
This report documents the findings related to a review of power sources for six off-grid Road Weather Information Systems (RWIS) in : Alaska. Various power sources were reviewed as a means of reliably operating the off-grid RWIS sites throughout the ...
A Phase I Feasibility Study of Yoga on the Physical Health and Coping of Informal Caregivers
Directory of Open Access Journals (Sweden)
Marieke Van Puymbroeck
2007-01-01
Full Text Available Family and friends who provide unpaid care to an individual with a disease or disability (known as informal caregivers experience numerous threats to their physical health as a result of providing care. In spite of evidence that participation in physical and leisure activities can be health promoting, informal caregivers have reported diminished or completely absent leisure participation. Hatha yoga has documented therapeutic benefits, including reduced anxiety, as well as improved muscle strength and endurance and flexibility. The purpose of this study was to determine the feasibility of conducting an 8-week yoga program with informal caregivers, and to gather pilot data on the effects of yoga on the physical fitness and coping of informal caregivers. Caregivers were randomized into a yoga intervention (n = 8 or control group (n = 9. The yoga sessions were 2.5 hours/week for 8 weeks and consisted of a variety of pranayama (breathing and asana (postures activities and were led by a certified yoga instructor. Four caregivers (two in each group dropped out of the study. After the conclusion of the 8-week yoga program, lower body strength increased significantly for those in the yoga group and other notable trends occurred in terms of coping, upper body strength and aerobic endurance. Caregivers in the control group experienced an unexpected increase in lower body flexibility. These findings indicate that caregivers in a yoga program may receive some benefits. Future studies are encouraged to test the efficacy of yoga as an intervention for caregivers.
Phases and Steps in the Access to Data in Information Tools
DEFF Research Database (Denmark)
Bergenholtz, Henning; Bothma, Theo; Gouws, Rufus
2015-01-01
route and access time, but not access structure. This term is not only ill defined – it is less relevant, because each user has different access routes, and also the same user makes use of different routes in different cases. We describe four experiments in a case study with one test person how...... the different access processes in different user situations take place. This test person is trying to solve different accounting information needs in different user situations. The aim of this paper is to compare and contrast the access process terminology of lexicography and information science, to systematize...... the terms in a logical structure and to show how these disciplines complement one another by providing clearer definitions to describe the different access processes....
Hospital budget increase for information technology during phase 1 meaningful use.
Neumeier, Harold; Berner, Eta S; Burke, Darrell E; Azuero, Andres
2015-01-01
Federal policies have a significant effect on how businesses spend money. The 2009 HITECH (Health Information Technology for Economic and Clinical Health Act) authorized incentive payments through Medicare and Medicaid to clinicians and hospitals when they use certified electronic health records privately and securely to achieve specified improvements in care delivery. Federal incentive payments were offered in 2011 for hospitals that had satisfied "meaningful use" criteria. A longitudinal study of nonfederal hospital information technology (IT) budgets (N = 493) during the years 2009 to 2011 found increases in the percentage of hospital annual operating budgets allocated to IT in the years leading up to these federal incentives. This increase was most pronounced among hospitals receiving high proportions of their reimbursements from Medicaid, followed by hospitals receiving high proportions of their reimbursements from Medicare, possibly indicating a budget shift during this period to more IT spending to achieve meaningful-use policy guidelines.
Informing the Long-Term Learner Model: Motivating the Adult Learner (Phase 1)
2017-09-28
memory systems: 1) short - term memory , 2) working memory , and 3) long - term memory . The short - term memory stores the information for brief periods of...and the episodic buffer, which is linked to long - term memory . The visual working memory shares parts and interacts with attention (Gazzaley and...Nobre 2012; Zanto et al. 2011). Short - term memory is limited in its importance to
Garat, Alcides
How complex numbers get into play in a non-trivial way in real theories of gravitation is relevant since in a unified structure they should be able to relate in a natural way with quantum theories. For a long time this issue has been lingering on both relativistic formulations and quantum theories. We will analyze this fundamental subject under the light of new group isomorphism theorems linking local internal groups of transformations and local groups of spacetime transformations. The bridge between these two kinds of transformations is represented by new tetrads introduced previously. It is precisely through these local tetrad structures that we will provide a non-trivial answer to this old issue. These new tetrads have two fundamental building components, the skeletons and the gauge vectors. It is these constructive elements that provide the mathematical support that allows to prove group isomorphism theorems. In addition to this, we will prove a unique new property, the infinite tetrad nesting, alternating the nesting with non-Abelian tetrads in the construction of the tetrad gauge vectors. As an application we will demonstrate an alternative proof of a new group isomorphism theorem.
Qin, Yi; Wang, Zhipeng; Wang, Hongjuan; Gong, Qiong; Zhou, Nanrun
2018-06-01
The diffractive-imaging-based encryption (DIBE) scheme has aroused wide interesting due to its compact architecture and low requirement of conditions. Nevertheless, the primary information can hardly be recovered exactly in the real applications when considering the speckle noise and potential occlusion imposed on the ciphertext. To deal with this issue, the customized data container (CDC) into DIBE is introduced and a new phase retrieval algorithm (PRA) for plaintext retrieval is proposed. The PRA, designed according to the peculiarity of the CDC, combines two key techniques from previous approaches, i.e., input-support-constraint and median-filtering. The proposed scheme can guarantee totally the reconstruction of the primary information despite heavy noise or occlusion and its effectiveness and feasibility have been demonstrated with simulation results.
Charroud, Céline; Steffener, Jason; Le Bars, Emmanuelle; Deverdun, Jérémy; Bonafe, Alain; Abdennour, Meriem; Portet, Florence; Molino, François; Stern, Yaakov; Ritchie, Karen; Menjot de Champfleur, Nicolas; Akbaraly, Tasnime N
2015-11-01
Changes in working memory are sensitive indicators of both normal and pathological brain aging and associated disability. The present study aims to further understanding of working memory in normal aging using a large cohort of healthy elderly in order to examine three separate phases of information processing in relation to changes in task load activation. Using covariance analysis, increasing and decreasing neural activation was observed on fMRI in response to a delayed item recognition task in 337 cognitively healthy elderly persons as part of the CRESCENDO (Cognitive REServe and Clinical ENDOphenotypes) study. During three phases of the task (stimulation, retention, probe), increased activation was observed with increasing task load in bilateral regions of the prefrontal cortex, parietal lobule, cingulate gyrus, insula and in deep gray matter nuclei, suggesting an involvement of central executive and salience networks. Decreased activation associated with increasing task load was observed during the stimulation phase, in bilateral temporal cortex, parietal lobule, cingulate gyrus and prefrontal cortex. This spatial distribution of decreased activation is suggestive of the default mode network. These findings support the hypothesis of an increased activation in salience and central executive networks and a decreased activation in default mode network concomitant to increasing task load. Copyright © 2015 Elsevier Inc. All rights reserved.
International Nuclear Information System (INIS)
Ortigosa, Nuria; Fernández, Carmen; Galbis, Antonio; Cano, Óscar
2015-01-01
Patients suffering from atrial fibrillation can be classified into different subtypes, according to the temporal pattern of the arrhythmia and its recurrence. Nowadays, clinicians cannot differentiate a priori between the different subtypes, and patient classification is done afterwards, when its clinical course is available. In this paper we present a comparison of classification performances when differentiating paroxysmal and persistent atrial fibrillation episodes by means of support vector machines. We analyze short surface electrocardiogram recordings by extracting modulus and phase features from several time-frequency transforms: short-time Fourier transform, Wigner–Ville, Choi–Williams, Stockwell transform, and general Fourier-family transform. Overall, accuracy higher than 81% is obtained when classifying phase information features of real test ECGs from a heterogeneous cohort of patients (in terms of progression of the arrhythmia and antiarrhythmic treatment) recorded in a tertiary center. Therefore, phase features can facilitate the clinicians’ choice of the most appropriate treatment for each patient by means of a non-invasive technique (the surface ECG). (paper)
Perron, Aurelien; Roehling, John D.; Turchi, Patrice E. A.; Fattebert, Jean-Luc; McKeown, Joseph T.
2018-01-01
A combination of dynamic transmission electron microscopy (DTEM) experiments and CALPHAD-informed phase-field simulations was used to study rapid solidification in Cu-Ni thin-film alloys. Experiments—conducted in the DTEM—consisted of in situ laser melting and determination of the solidification kinetics by monitoring the solid-liquid interface and the overall microstructure evolution (time-resolved measurements) during the solidification process. Modelling of the Cu-Ni alloy microstructure evolution was based on a phase-field model that included realistic Gibbs energies and diffusion coefficients from the CALPHAD framework (thermodynamic and mobility databases). DTEM and post mortem experiments highlighted the formation of microsegregation-free columnar grains with interface velocities varying from ˜0.1 to ˜0.6 m s-1. After an ‘incubation’ time, the velocity of the planar solid-liquid interface accelerated until solidification was complete. In addition, a decrease of the temperature gradient induced a decrease in the interface velocity. The modelling strategy permitted the simulation (in 1D and 2D) of the solidification process from the initially diffusion-controlled to the nearly partitionless regimes. Finally, results of DTEM experiments and phase-field simulations (grain morphology, solute distribution, and solid-liquid interface velocity) were consistent at similar time (μs) and spatial scales (μm).
Quantum anomalous Hall phase in a one-dimensional optical lattice
Liu, Sheng; Shao, L. B.; Hou, Qi-Zhe; Xue, Zheng-Yuan
2018-03-01
We propose to simulate and detect quantum anomalous Hall phase with ultracold atoms in a one-dimensional optical lattice, with the other synthetic dimension being realized by modulating spin-orbit coupling. We show that the system manifests a topologically nontrivial phase with two chiral edge states which can be readily detected in this synthetic two-dimensional system. Moreover, it is interesting that at the phase transition point there is a flat energy band and this system can also be in a topologically nontrivial phase with two Fermi zero modes existing at the boundaries by considering the synthetic dimension as a modulated parameter. We also show how to measure these topological phases experimentally in ultracold atoms. Another model with a random Rashba and Dresselhaus spin-orbit coupling strength is also found to exhibit topological nontrivial phase, and the impact of the disorder to the system is revealed.
Energy Technology Data Exchange (ETDEWEB)
Barancik, J.I.; Kramer, C.F.; Thode, H.C. Jr.
1995-12-01
BNL is developing and implementing the project ``Geographic Information System (GIS) for Long Island`` to address the potential relationship of environmental and occupational exposures to breast cancer etiology on Long Island. The project is divided into two major phases: The four month-feasibility project (Phase 1), and the major development and implementation project (Phase 2). This report summarizes the work completed in the four month Phase 1 Project, ``Feasibility of a Geographic Information System for Long Island.`` It provides the baseline information needed to further define and prioritize the scope of work for subsequent tasks. Phase 2 will build upon this foundation to develop an operational GIS for the Long Island Breast Cancer Study Project (LIBCSP).
International Nuclear Information System (INIS)
Barancik, J.I.; Kramer, C.F.; Thode, H.C. Jr.
1995-01-01
BNL is developing and implementing the project ''Geographic Information System (GIS) for Long Island'' to address the potential relationship of environmental and occupational exposures to breast cancer etiology on Long Island. The project is divided into two major phases: The four month-feasibility project (Phase 1), and the major development and implementation project (Phase 2). This report summarizes the work completed in the four month Phase 1 Project, ''Feasibility of a Geographic Information System for Long Island.'' It provides the baseline information needed to further define and prioritize the scope of work for subsequent tasks. Phase 2 will build upon this foundation to develop an operational GIS for the Long Island Breast Cancer Study Project (LIBCSP)
International Nuclear Information System (INIS)
Sullivan, T.J.
2003-01-01
Full text: Nuclear accidents/incidents cause significant fear in citizens perceived to be (potentially) impacted. Such events challenge national governments and international agencies to quickly and confidently provide assurance and protection advice. Based on the experience of several radiological accidents, e.g., Three Mile Island, Chernobyl, Algeciras, etc., it is evident that large areas, frequently transboundary, and numbers of citizens have the potential to be impacted. Additionally, as a consequence of current 'globalization', i.e. governmental, business, education and leisure travel, most nations now daily host numerous international visitors whose national government embassies have a responsibility to advise and project them from hazards. This mixture of large area, transboundary and international mobility presents a significant challenge to the decision maker community in order to deliver the best consistent advice to all those potentially impacted by a nuclear accident (and assure those not impacted). Post-Chernobyl there has been definitive progress and agreement in the determination of dose protection thresholds. In the same time period there has been a proliferation of dispersion models and assessment systems (from the local to the international scale) to support decision makers at all levels of government. Unfortunately, due to the varying parameters of scale, resolution, input data, and physics assumptions, the consequent assessment results can vary substantially enough [Atmes] to potentially cause confusion and even contradiction when presented to decision makers. Such a circumstance potentially leads to wrong decisions, undercuts confidence and negates all the work and benefits of good assessment calculations. From 1996 to 1999 Japan (JAERI) and the USA (LLNL) investigated, developed and tested an initial capability to share basic event information (start time, source/rates, local meteorology, local measurements, etc.) and calculated assessment
Phase II Practice-based Evidence in Nutrition (PEN) evaluation: interviews with key informants.
Bowden, Fran Martin; Lordly, Daphne; Thirsk, Jayne; Corby, Lynda
2012-01-01
Dietitians of Canada has collaborated with experts in knowledge translation and transfer, technology, and dietetic practice to develop and implement an innovative online decision-support system called Practice-based Evidence in Nutrition (PEN). A study was conducted to evaluate the perceived facilitators and barriers that enable dietitians to use or prevent them from using PEN. As part of the overall evaluation framework of PEN, a qualitative descriptive research design was used to address the research purpose. Individual, semi-structured telephone interviews with 17 key informants were completed, and the interview transcripts underwent qualitative content analysis. Respondents identified several facilitators of and barriers to PEN use. Facilitators included specificity to dietetics, rigorous/expert review, easy accessibility, current content, credible/secure material, well-organized/easy-to-use material, material that is valuable to practice, and good value for money. Barriers included perceived high cost, fee structuring/cost to students, certain organizational aspects, and a perceived lack of training for pathway contributors. This formative evaluation has indicated areas in which PEN could be improved and strategies to make PEN the standard for dietetic education and practice. Ensuring that PEN is meeting users' knowledge needs is of the utmost importance if dietitians are to remain on the cutting edge of scientific inquiry.
Ma, Fengxian; Gao, Guoping; Jiao, Yalong; Gu, Yuantong; Bilic, Ante; Zhang, Haijun; Chen, Zhongfang; Du, Aijun
2016-02-01
Single layered transition metal dichalcogenides have attracted tremendous research interest due to their structural phase diversities. By using a global optimization approach, we have discovered a new phase of transition metal dichalcogenides (labelled as T''), which is confirmed to be energetically, dynamically and kinetically stable by our first-principles calculations. The new T'' MoS2 phase exhibits an intrinsic quantum spin Hall (QSH) effect with a nontrivial gap as large as 0.42 eV, suggesting that a two-dimensional (2D) topological insulator can be achieved at room temperature. Most interestingly, there is a topological phase transition simply driven by a small tensile strain of up to 2%. Furthermore, all the known MX2 (M = Mo or W; X = S, Se or Te) monolayers in the new T'' phase unambiguously display similar band topologies and strain controlled topological phase transitions. Our findings greatly enrich the 2D families of transition metal dichalcogenides and offer a feasible way to control the electronic states of 2D topological insulators for the fabrication of high-speed spintronics devices.Single layered transition metal dichalcogenides have attracted tremendous research interest due to their structural phase diversities. By using a global optimization approach, we have discovered a new phase of transition metal dichalcogenides (labelled as T''), which is confirmed to be energetically, dynamically and kinetically stable by our first-principles calculations. The new T'' MoS2 phase exhibits an intrinsic quantum spin Hall (QSH) effect with a nontrivial gap as large as 0.42 eV, suggesting that a two-dimensional (2D) topological insulator can be achieved at room temperature. Most interestingly, there is a topological phase transition simply driven by a small tensile strain of up to 2%. Furthermore, all the known MX2 (M = Mo or W; X = S, Se or Te) monolayers in the new T'' phase unambiguously display similar band topologies and strain controlled topological
Quantum rewinding via phase estimation
Tabia, Gelo Noel
2015-03-01
In cryptography, the notion of a zero-knowledge proof was introduced by Goldwasser, Micali, and Rackoff. An interactive proof system is said to be zero-knowledge if any verifier interacting with an honest prover learns nothing beyond the validity of the statement being proven. With recent advances in quantum information technologies, it has become interesting to ask if classical zero-knowledge proof systems remain secure against adversaries with quantum computers. The standard approach to show the zero-knowledge property involves constructing a simulator for a malicious verifier that can be rewinded to a previous step when the simulation fails. In the quantum setting, the simulator can be described by a quantum circuit that takes an arbitrary quantum state as auxiliary input but rewinding becomes a nontrivial issue. Watrous proposed a quantum rewinding technique in the case where the simulation's success probability is independent of the auxiliary input. Here I present a more general quantum rewinding scheme that employs the quantum phase estimation algorithm. This work was funded by institutional research grant IUT2-1 from the Estonian Research Council and by the European Union through the European Regional Development Fund.
Design of Collaborative Information Agents
Jonker, C.M.; Klusch, M.; Treur, J.; Klusch, M.; Kerschberg, L.
2000-01-01
Effective development of nontrivial systems of collaborative information agents requires that an in-depth analysis is made resulting in (1) specification of requirements at different levels of the system, (2) specification of design structures, and (3) a systematic verification. To support a
Energy Technology Data Exchange (ETDEWEB)
Bočan, Jiří [Laboratory of Nanostructures and Nanomaterials, Institute of Physics, Czech Academy of Sciences, Na Slovance 1999/2, CZ-12821 Praha 8 (Czech Republic); Tsurekawa, Sadahiro [Division of Materials Science, Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Jäger, Aleš, E-mail: aljag@seznam.cz [Laboratory of Nanostructures and Nanomaterials, Institute of Physics, Czech Academy of Sciences, Na Slovance 1999/2, CZ-12821 Praha 8 (Czech Republic)
2017-02-27
Micropillars with a nontrivial cross-sectional shape but constant cross-sectional area were fabricated from a pure magnesium single crystal with (0001) orientation by a focused gallium ion beam using a modified annular milling method. The basic mechanical properties (compressive modulus, strength at different plastic strain levels and hardening exponent) of those structures were determined under compression by means of in situ nanoindentation in scanning electron microscope and correlated by the micropillar cross-sectional circumference. It was observed that the modulus and strength increased with increasing circumference. The values of the modulus for the complex cross sectional shapes are on average higher by 5%, and the yield strength, ranging between 274 MPa and 342 MPa, is on average higher by 20% relative to micropillars with a simple circular or polygonal cross section. Surprisingly, the hardening exponent remains nearly constant regardless of the micropillar cross section.
Chiral Floquet Phases of Many-Body Localized Bosons
Directory of Open Access Journals (Sweden)
Hoi Chun Po
2016-12-01
Full Text Available We construct and classify chiral topological phases in driven (Floquet systems of strongly interacting bosons, with finite-dimensional site Hilbert spaces, in two spatial dimensions. The construction proceeds by introducing exactly soluble models with chiral edges, which in the presence of many-body localization (MBL in the bulk are argued to lead to stable chiral phases. These chiral phases do not require any symmetry and in fact owe their existence to the absence of energy conservation in driven systems. Surprisingly, we show that they are classified by a quantized many-body index, which is well defined for any MBL Floquet system. The value of this index, which is always the logarithm of a positive rational number, can be interpreted as the entropy per Floquet cycle pumped along the edge, formalizing the notion of quantum-information flow. We explicitly compute this index for specific models and show that the nontrivial topology leads to edge thermalization, which provides an interesting link between bulk topology and chaos at the edge. We also discuss chiral Floquet phases in interacting fermionic systems and their relation to chiral bosonic phases.
Phase dynamics of low critical current density YBCO Josephson junctions
Energy Technology Data Exchange (ETDEWEB)
Massarotti, D., E-mail: dmassarotti@na.infn.it [Dipartimento di Fisica, Università degli Studi di Napoli Federico II, Via Cinthia, 80126 Napoli (Italy); CNR-SPIN UOS Napoli, Complesso Universitario di Monte Sant’Angelo, Via Cinthia, 80126 Napoli (Italy); Stornaiuolo, D. [Dipartimento di Fisica, Università degli Studi di Napoli Federico II, Via Cinthia, 80126 Napoli (Italy); Rotoli, G. [Dipartimento di Ingegneria Industriale e dell’Informazione, Seconda Università di Napoli, Via Roma 29, 81031 Aversa (CE) (Italy); Carillo, F. [Nest, Scuola Normale Superiore, Piazza San Silvestro 12, 56126 Pisa (Italy); Galletti, L. [Dipartimento di Fisica, Università degli Studi di Napoli Federico II, Via Cinthia, 80126 Napoli (Italy); CNR-SPIN UOS Napoli, Complesso Universitario di Monte Sant’Angelo, Via Cinthia, 80126 Napoli (Italy); Longobardi, L. [Dipartimento di Ingegneria Industriale e dell’Informazione, Seconda Università di Napoli, Via Roma 29, 81031 Aversa (CE) (Italy); American Physical Society, 1 Research Road, Ridge, NY 11961 (United States); Beltram, F. [Nest, Scuola Normale Superiore, Piazza San Silvestro 12, 56126 Pisa (Italy); Tafuri, F. [CNR-SPIN UOS Napoli, Complesso Universitario di Monte Sant’Angelo, Via Cinthia, 80126 Napoli (Italy); Dipartimento di Ingegneria Industriale e dell’Informazione, Seconda Università di Napoli, Via Roma 29, 81031 Aversa (CE) (Italy)
2014-08-15
Highlights: • We study the phase dynamics of YBaCuO Josephson junctions using various tools. • We derive information on the dissipation in a wide range of transport parameters. • Dissipation in such devices can be described by a frequency dependent damping model. • The use of different substrates allows us to tune the shell circuit. - Abstract: High critical temperature superconductors (HTS) based devices can have impact in the study of the phase dynamics of Josephson junctions (JJs) thanks to the wide range of junction parameters they offer and to their unconventional properties. Measurements of current–voltage characteristics and of switching current distributions constitute a direct way to classify different regimes of the phase dynamics and of the transport, also in nontrivial case of the moderately damped regime (MDR). MDR is going to be more and more common in JJs with advances in nanopatterning superconductors and synthesizing novel hybrid systems. Distinctive signatures of macroscopic quantum tunneling and of thermal activation in presence of different tunable levels of dissipation have been detected in YBCO grain boundary JJs. Experimental data are supported by Monte Carlo simulations of the phase dynamics, in a wide range of temperatures and dissipation levels. This allows us to quantify dissipation in the MDR and partially reconstruct a phase diagram as guideline for a wide range of moderately damped systems.
International Nuclear Information System (INIS)
Boyard, Pierre.
1981-01-01
The fear for nuclear energy and more particularly for radioactive wastes is analyzed in the sociological context. Everybody agree on the information need, information is available but there is a problem for their diffusion. Reactions of the public are analyzed and journalists, scientists and teachers have a role to play [fr
Nontrivial Pfaffian forms in cosmology
International Nuclear Information System (INIS)
Lukacs, B.; Paal, G.
1989-01-01
The compatibility of possible continuous cosmological particle production with thermodynamics was studied. It was found that with the usual K=2 Pfaffian (dQ=TdS) the compatibility held only in very special cases. K≥3 Pfaffians could easily be reconciled with continuous production. Since in this case the full thermodynamic state space was accessible by quasistatic adiabatic processes, such systems showed local rather than global irreversibility. This fact may prevent Heat Death even in indefinitely old model Universes. (author) 36 refs
Moving walls and geometric phases
Energy Technology Data Exchange (ETDEWEB)
Facchi, Paolo, E-mail: paolo.facchi@ba.infn.it [Dipartimento di Fisica and MECENAS, Università di Bari, I-70126 Bari (Italy); INFN, Sezione di Bari, I-70126 Bari (Italy); Garnero, Giancarlo, E-mail: giancarlo.garnero@uniba.it [Dipartimento di Fisica and MECENAS, Università di Bari, I-70126 Bari (Italy); INFN, Sezione di Bari, I-70126 Bari (Italy); Marmo, Giuseppe [Dipartimento di Scienze Fisiche and MECENAS, Università di Napoli “Federico II”, I-80126 Napoli (Italy); INFN, Sezione di Napoli, I-80126 Napoli (Italy); Samuel, Joseph [Raman Research Institute, 560080 Bangalore (India)
2016-09-15
We unveil the existence of a non-trivial Berry phase associated to the dynamics of a quantum particle in a one dimensional box with moving walls. It is shown that a suitable choice of boundary conditions has to be made in order to preserve unitarity. For these boundary conditions we compute explicitly the geometric phase two-form on the parameter space. The unboundedness of the Hamiltonian describing the system leads to a natural prescription of renormalization for divergent contributions arising from the boundary.
Assessing the efficiency of information protection systems in the computer systems and networks
Nachev, Atanas; Zhelezov, Stanimir
2015-01-01
The specific features of the information protection systems in the computer systems and networks require the development of non-trivial methods for their analysis and assessment. Attempts for solutions in this area are given in this paper.
Topological Phase Diagrams of Bulk and Monolayer TiS2−xTex
Zhu, Zhiyong; Cheng, Yingchun; Schwingenschlö gl, Udo
2013-01-01
With the use of ab initio calculations, the topological phase diagrams of bulk and monolayer TiS2−xTex are established. Whereas bulk TiS2−xTex shows two strong topological phases [1;(000)] and [1;(001)] for 0.44
Topological Phase Diagrams of Bulk and Monolayer TiS2−xTex
Zhu, Zhiyong
2013-02-12
With the use of ab initio calculations, the topological phase diagrams of bulk and monolayer TiS2−xTex are established. Whereas bulk TiS2−xTex shows two strong topological phases [1;(000)] and [1;(001)] for 0.44
Wen, Gaiyan; Liu, Xinchun; Huang, Lihua; Shu, Jingxian; Xu, Nana; Chen, Ruifang; Huang, Zhijun; Yang, Guoping; Wang, Xiaomin; Xiang, Yuxia; Lu, Yao; Yuan, Hong
2016-01-01
To explore the readability and content integrity of informed consent forms (ICFs) used in China and to compare the quality of Chinese local ICFs with that of international ICFs. The length, readability and content of 155 consent documents from phase II-IV drug clinical trials from the Third Xiangya Hospital Ethics Committee from November 2009 to January 2015 were evaluated. Reading difficulty was tested using a readability formula adapted for the Chinese language. An ICF checklist containing 27 required elements was successfully constructed to evaluate content integrity. The description of alternatives to participation was assessed. The quality of ICFs from different sponsorships were also compared. Among the 155 evaluable trials, the ICFs had a median length of 5286 words, corresponding to 7 pages. The median readability score was 4.31 (4.02-4.41), with 63.9% at the 2nd level and 36.1% at the 3rd level. Five of the 27 elements were frequently neglected. The average score for the description of alternatives to participation was 1.06, and 27.7% of the ICFs did not mention any alternatives. Compared with Chinese local ICFs, international ICFs were longer, more readable and contained more of the required elements (P readability and content integrity than Chinese local ICFs. More efforts should thus be made to improve the quality of consent documents in China.
Wang, Y; Wang, C; Zhang, Z
2018-05-01
Automated cell segmentation plays a key role in characterisations of cell behaviours for both biology research and clinical practices. Currently, the segmentation of clustered cells still remains as a challenge and is the main reason for false segmentation. In this study, the emphasis was put on the segmentation of clustered cells in negative phase contrast images. A new method was proposed to combine both light intensity and cell shape information through the construction of grey-weighted distance transform (GWDT) within preliminarily segmented areas. With the constructed GWDT, the clustered cells can be detected and then separated with a modified region skeleton-based method. Moreover, a contour expansion operation was applied to get optimised detection of cell boundaries. In this paper, the working principle and detailed procedure of the proposed method are described, followed by the evaluation of the method on clustered cell segmentation. Results show that the proposed method achieves an improved performance in clustered cell segmentation compared with other methods, with 85.8% and 97.16% accuracy rate for clustered cells and all cells, respectively. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.
Energy Technology Data Exchange (ETDEWEB)
Blaylock, Myra L.; LaFleur, Chris Bensdotter; Muna, Alice Baca; Ehrhart, Brian David
2018-03-01
Safety standards development for maintenance facilities of liquid and compressed natural gas fueled vehicles is required to ensure proper facility design and operating procedures. Standard development organizations are utilizing risk-informed concepts to develop natural gas vehicle (NGV) codes and standards so that maintenance facilities meet acceptable risk levels. The present report summarizes Phase II work for existing NGV repair facility code requirements and highlights inconsistencies that need quantitative analysis into their effectiveness. A Hazardous and Operability study was performed to identify key scenarios of interest using risk ranking. Detailed simulations and modeling were performed to estimate the location and behavior of natural gas releases based on these scenarios. Specific code conflicts were identified, and ineffective code requirements were highlighted and resolutions proposed. These include ventilation rate basis on area or volume, as well as a ceiling offset which seems ineffective at protecting against flammable gas concentrations. ACKNOWLEDGEMENTS The authors gratefully acknowledge Bill Houf (SNL -- Retired) for his assistance with the set-up and post-processing of the numerical simulations. The authors also acknowledge Doug Horne (retired) for his helpful discussions. We would also like to acknowledge the support from the Clean Cities program of DOE's Vehicle Technology Office.
Lattice quantum phase space and Yang-Baxter equation
International Nuclear Information System (INIS)
Djemai, A.E.F.
1995-04-01
In this work, we show that it is possible to construct the quantum group which preserves the quantum symplectic structure introduced in the context of the matrix Hamiltonian formalism. We also study the braiding existing behind the lattice quantum phase space, and present another type of non-trivial solution to the resulting Yang-Baxter equation. (author). 20 refs, 1 fig
Buchanan, John J
2016-01-01
The primary goal of this chapter is to merge together the visual perception perspective of observational learning and the coordination dynamics theory of pattern formation in perception and action. Emphasis is placed on identifying movement features that constrain and inform action-perception and action-production processes. Two sources of visual information are examined, relative motion direction and relative phase. The visual perception perspective states that the topological features of relative motion between limbs and joints remains invariant across an actor's motion and therefore are available for pickup by an observer. Relative phase has been put forth as an informational variable that links perception to action within the coordination dynamics theory. A primary assumption of the coordination dynamics approach is that environmental information is meaningful only in terms of the behavior it modifies. Across a series of single limb tasks and bimanual tasks it is shown that the relative motion and relative phase between limbs and joints is picked up through visual processes and supports observational learning of motor skills. Moreover, internal estimations of motor skill proficiency and competency are linked to the informational content found in relative motion and relative phase. Thus, the chapter links action to perception and vice versa and also links cognitive evaluations to the coordination dynamics that support action-perception and action-production processes.
Directory of Open Access Journals (Sweden)
Egon Lichetenberger
1950-10-01
Full Text Available Informe del doctor Egon Lichetenberger ante el Consejo Directivo de la Facultad, sobre el curso de especialización en Anatomía Patológica patrocinado por la Kellogg Foundation (Departamento de Patología
International Nuclear Information System (INIS)
Dai, Chaoqing; Wang, Xiaogang; Zhou, Guoquan; Chen, Junlang
2014-01-01
An image-hiding method based on the optical interference principle and partial-phase-truncation in the fractional Fourier domain is proposed. The primary image is converted into three phase-only masks (POMs) using an analytical algorithm involved partial-phase-truncation and a fast random pixel exchange process. A procedure of a fake silhouette for a decryption key is suggested to reinforce the encryption and give a hint of the position of the key. The fractional orders of FrFT effectively enhance the security of the system. In the decryption process, the POM with false information and the other two POMs are, respectively, placed in the input and fractional Fourier planes to recover the primary image. There are no unintended information disclosures and iterative computations involved in the proposed method. Simulation results are presented to verify the validity of the proposed approach. (letters)
Directory of Open Access Journals (Sweden)
Feng Yang
2013-06-01
Full Text Available Non-rigid multi-modal image registration plays an important role in medical image processing and analysis. Existing image registration methods based on similarity metrics such as mutual information (MI and sum of squared differences (SSD cannot achieve either high registration accuracy or high registration efficiency. To address this problem, we propose a novel two phase non-rigid multi-modal image registration method by combining Weber local descriptor (WLD based similarity metrics with the normalized mutual information (NMI using the diffeomorphic free-form deformation (FFD model. The first phase aims at recovering the large deformation component using the WLD based non-local SSD (wldNSSD or weighted structural similarity (wldWSSIM. Based on the output of the former phase, the second phase is focused on getting accurate transformation parameters related to the small deformation using the NMI. Extensive experiments on T1, T2 and PD weighted MR images demonstrate that the proposed wldNSSD-NMI or wldWSSIM-NMI method outperforms the registration methods based on the NMI, the conditional mutual information (CMI, the SSD on entropy images (ESSD and the ESSD-NMI in terms of registration accuracy and computation efficiency.
Analyzing phase diagrams and phase transitions in networked competing populations
Ni, Y.-C.; Yin, H. P.; Xu, C.; Hui, P. M.
2011-03-01
Phase diagrams exhibiting the extent of cooperation in an evolutionary snowdrift game implemented in different networks are studied in detail. We invoke two independent payoff parameters, unlike a single payoff often used in most previous works that restricts the two payoffs to vary in a correlated way. In addition to the phase transition points when a single payoff parameter is used, phase boundaries separating homogeneous phases consisting of agents using the same strategy and a mixed phase consisting of agents using different strategies are found. Analytic expressions of the phase boundaries are obtained by invoking the ideas of the last surviving patterns and the relative alignments of the spectra of payoff values to agents using different strategies. In a Watts-Strogatz regular network, there exists a re-entrant phenomenon in which the system goes from a homogeneous phase into a mixed phase and re-enters the homogeneous phase as one of the two payoff parameters is varied. The non-trivial phase diagram accompanying this re-entrant phenomenon is quantitatively analyzed. The effects of noise and cooperation in randomly rewired Watts-Strogatz networks are also studied. The transition between a mixed phase and a homogeneous phase is identify to belong to the directed percolation universality class. The methods used in the present work are applicable to a wide range of problems in competing populations of networked agents.
Saveleiv, I. K.; Sharova, N. V.; Tarasenko, M. Yu; Yalunina, T. R.; Davydov, V. V.; Rud', V. Yu
2017-11-01
The results of the research of the developed fiber-optic transmission systems for analog high frequency signal are represented. On its basis, a new method to identify various structural defects in the active phased antenna arrays is elaborated.
Zak Phase in Discrete-Time Quantum Walks
Puentes, G.; Santillán, O.
2015-01-01
We report on a simple scheme that may present a non-trivial geometric Zak phase ($\\Phi_{Zak}$) structure, which is based on a discrete-time quantum walk architecture. By detecting the Zak phase difference between two trajectories connecting adjacent Dirac points where the quasi-energy gap closes for opposite values of quasi-momentum ($k$), it is possible to identify geometric invariants. These geometric invariants correspond to $|\\Phi_{Zak}^{+(-)}-\\Phi_{Zak}^{-(+)}|=\\pi$ and $|\\Phi_{Zak}^{+(-...
International Nuclear Information System (INIS)
Zissiadis, Yvonne; Harper, Emily; Kearney, Elizabeth
2010-01-01
Background and purpose: A diagnosis of malignancy and its treatment is a very stressful time for patients and their families. This study was conducted to determine the impact of more intensive written information on patients' anxiety levels. The secondary aim was to determine the impact of this information on patients' satisfaction levels. Materials and methods: This prospective randomized trial consisted of patients with a pathological diagnosis of cancer having radical radiotherapy (RT). Patients were randomized to receive the more intensive information (including written information and a telephone call from the research nurse) or not to receive the more intensive information at the time of their initial consultation with the radiation oncologist. Study questionnaires measuring anxiety (STAI form) were completed prior to their first consultation (baseline) at the time of simulation (pre-RT) and at the completion of radiotherapy. A second questionnaire assessing satisfaction with the information given (ISQ) was completed at the time of simulation prior to commencing RT. Results: One hundred and ninety-four patients were enrolled in the study. The mean age of the patients was 58.5 years and 70% of patients were female. Breast cancer (67%) was the commonest cancer. One hundred and two patients were randomized to receive the intensive information package and 92 patients received the standard consultation. There was no significant difference in mean State or Trait anxiety scores between any of the time intervals and no difference between the two information groups. There was no significant difference between the groups with regard to mean satisfaction scores with the overall information given, nor with any individual question. The satisfaction scores with lifestyle information given were lower than those for any other type of information in both randomization arms. Conclusion: More intensive information did not significantly change patients' anxiety scores or
Energy Technology Data Exchange (ETDEWEB)
Alsari, S., E-mail: s.alsari@imperial.ac.uk; Aslaninejad, M.; Pozimski, J.
2015-03-01
For the Front End Test Stand (FETS) linear accelerator project at the Rutherford Appleton Laboratory in the UK, a 4 m, 4 vanes Radio Frequency Quadrupole (RFQ) with a resonant frequency of 324 MHz has been designed. The RF power feeding the RFQ gives rise to the temperature increase in the RFQ, which in turn, results in shifting the resonant frequency of the RFQ. The frequency shift and the stability in the RFQ frequency can be maintained based on the reflected power or signal phase information. We have, however, investigated restoration of the RFQ nominal frequency based on the RF signal phases driving a stepper motor. The concept and the system set-up and electronics are described in detail. Results of the measurements indicating the full restoration of the RFQ nominal frequency based on the RF signal phases and stepper motor are presented. Moreover, measured sensitivity of tuner with respect to its position is given.
International Nuclear Information System (INIS)
Alsari, S.; Aslaninejad, M.; Pozimski, J.
2015-01-01
For the Front End Test Stand (FETS) linear accelerator project at the Rutherford Appleton Laboratory in the UK, a 4 m, 4 vanes Radio Frequency Quadrupole (RFQ) with a resonant frequency of 324 MHz has been designed. The RF power feeding the RFQ gives rise to the temperature increase in the RFQ, which in turn, results in shifting the resonant frequency of the RFQ. The frequency shift and the stability in the RFQ frequency can be maintained based on the reflected power or signal phase information. We have, however, investigated restoration of the RFQ nominal frequency based on the RF signal phases driving a stepper motor. The concept and the system set-up and electronics are described in detail. Results of the measurements indicating the full restoration of the RFQ nominal frequency based on the RF signal phases and stepper motor are presented. Moreover, measured sensitivity of tuner with respect to its position is given
Freehafer, Douglas A.; Pierson, Oliver
2004-01-01
In the fall of 2002, the Onondaga Lake Partnership (OLP) formed a Geographic Information System (GIS) Planning Committee to begin the process of developing a comprehensive watershed geographic information system for Onondaga Lake. The goal of the Onondaga Lake Partnership geographic information system is to integrate the various types of spatial data used for scientific investigations, resource management, and planning and design of improvement projects in the Onondaga Lake Watershed. A needs-assessment survey was conducted and a spatial data framework developed to support the Onondaga Lake Partnership use of geographic information system technology. The design focused on the collection, management, and distribution of spatial data, maps, and internet mapping applications. A geographic information system library of over 100 spatial datasets and metadata links was assembled on the basis of the results of the needs assessment survey. Implementation options were presented, and the Geographic Information System Planning Committee offered recommendations for the management and distribution of spatial data belonging to Onondaga Lake Partnership members. The Onondaga Lake Partnership now has a strong foundation for building a comprehensive geographic information system for the Onondaga Lake watershed. The successful implementation of a geographic information system depends on the Onondaga Lake Partnership’s determination of: (1) the design and plan for a geographic information system, including the applications and spatial data that will be provided and to whom, (2) the level of geographic information system technology to be utilized and funded, and (3) the institutional issues of operation and maintenance of the system.
Mohamed, Abdel-Baset A.
2017-10-01
An analytical solution of the master equation that describes a superconducting cavity containing two coupled superconducting charge qubits is obtained. Quantum-mechanical correlations based on Wigner-Yanase skew information, as local quantum uncertainty and uncertainty-induced quantum non-locality, are compared to the concurrence under the effects of the phase decoherence. Local quantum uncertainty exhibits sudden changes during its time evolution and revival process. Sudden death and sudden birth occur only for entanglement, depending on the initial state of the two coupled charge qubits, while the correlations of skew information does not vanish. The quantum correlations of skew information are found to be sensitive to the dephasing rate, the photons number in the cavity, the interaction strength between the two qubits, and the qubit distribution angle of the initial state. With a proper initial state, the stationary correlation of the skew information has a non-zero stationary value for a long time interval under the phase decoherence, that it may be useful in quantum information and computation processes.
Energy Technology Data Exchange (ETDEWEB)
Perry, Frank Vinton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kelley, Richard E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Birdsell, Suzanne M. [Clark Univ., Worcester, MA (United States); Lugo, Alexander Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dobson, Patrick [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Houseworth, James [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2014-11-12
Reported is progress in the following areas: Phase 1 and 2 websites for the regional geology GIS database; terrane maps of crystalline basement rocks; inventory of shale formations in the US; and rock properties and in-situ conditions for shale estimated from sonic velocity measurements.
Shiozawa, Daiki; Sakagami, Takahide; Nakamura, Yu; Nonaka, Shinichi; Hamada, Kenichi
2017-12-06
Carbon fiber-reinforced plastic (CFRP) is widely used for structural members of transportation vehicles such as automobile, aircraft, or spacecraft, utilizing its excellent specific strength and specific rigidity in contrast with the metal. Short carbon fiber composite materials are receiving a lot of attentions because of their excellent moldability and productivity, however they show complicated behaviors in fatigue fracture due to the random fibers orientation. In this study, thermoelastic stress analysis (TSA) using an infrared thermography was applied to evaluate fatigue damage in short carbon fiber composites. The distribution of the thermoelastic temperature change was measured during the fatigue test, as well as the phase difference between the thermoelastic temperature change and applied loading signal. Evolution of fatigue damage was detected from the distribution of thermoelastic temperature change according to the thermoelastic damage analysis (TDA) procedure. It was also found that fatigue damage evolution was more clearly detected than before by the newly developed thermoelastic phase damage analysis (TPDA) in which damaged area was emphasized in the differential phase delay images utilizing the property that carbon fiber shows opposite phase thermoelastic temperature change.
Levesque, Janelle V; Lambert, Sylvie D; Girgis, Afaf; Turner, Jane; McElduff, Patrick; Kayser, Karen
2015-01-01
To (a) determine whether the information provided to men with prostate cancer and their partners in the immediate postdiagnostic phase met their needs; and (b) examine patient and partner satisfaction with the information received. Pre-intervention survey data from a pilot randomized controlled trial of a self-directed coping skills intervention involving 42 patients with prostate cancer, and their partners were collected to examine their psychosocial concerns/needs. The main concerns for patients and partners were psychosocial in nature such as managing emotions, concern about the future, and losing control. Overall, patients and partners received most information about tests and treatment options. Partners reported receiving significantly less information about support services ( P = 0.03) and self-care strategies ( P = 0.03) compared to patients. Partners also reported being significantly less satisfied with the information they received ( P = 0.007). Whereas medical information is routinely given, patients and partners may benefit from greater information about psychosocial issues arising from cancer. Despite increased recognition of partner's information needs these still remain unmet.
Directory of Open Access Journals (Sweden)
Janelle V Levesque
2015-01-01
Full Text Available Objective: To (a determine whether the information provided to men with prostate cancer and their partners in the immediate postdiagnostic phase met their needs; and (b examine patient and partner satisfaction with the information received. Methods: Pre-intervention survey data from a pilot randomized controlled trial of a self-directed coping skills intervention involving 42 patients with prostate cancer, and their partners were collected to examine their psychosocial concerns/needs. Results: The main concerns for patients and partners were psychosocial in nature such as managing emotions, concern about the future, and losing control. Overall, patients and partners received most information about tests and treatment options. Partners reported receiving significantly less information about support services (P = 0.03 and self-care strategies (P = 0.03 compared to patients. Partners also reported being significantly less satisfied with the information they received (P = 0.007. Conclusions: Whereas medical information is routinely given, patients and partners may benefit from greater information about psychosocial issues arising from cancer. Despite increased recognition of partner′s information needs these still remain unmet.
International Nuclear Information System (INIS)
Zhou Yunlong; Zhang Xueqing; Gao Yunpeng; Cheng Yue
2009-01-01
For studying flow regimes of gas/liquid two-phase in a vertical upward pipe, the conductance fluctuation information of four typical flow regimes was collected by a measuring the system with self-made multiple conductivity probes. Owing to the non-stationarity of conductance fluctuation signals of gas-liquid two-phase flow, a kind of' flow regime identification method based on wavelet packet Multi-scale Information Entropy and Hidden Markov Model (HMM) was put forward. First of all, the collected conductance fluctuation signals were decomposed into eight different frequency bands signals. Secondly, the wavelet packet multi-scale information entropy of different frequency bands signals were regarded as the input characteristic vectors of all states HMM which had been trained. In the end the regime identification of' the gas-liquid two-phase flow could be performed. The study showed that the method that HMM was applied to identify the flow regime was superior to the one that BP neural network was used, and the results proved that the method was efficient and feasible. (authors)
Mohamed, Abdel-Baset A.
2018-05-01
Analytical description for a Su(2)-quantum system interacting with a damped Su(1, 1)-cavity, which is filled with a non-linear Kerr medium, is presented. The dynamics of non-classicality of Su(1, 1)-state is investigated via the negative part of the Wigner function. We show that the negative part depends on the unitary interaction and the Kerr-like medium and it can be disappeared by increasing the dissipation rate and the detuning parameter. The phase space information of the Husimi function and its Wehrl density is very sensitive not only to the coupling to the environment and the unitary interaction but also to the detuning as well as to the Kerr-like medium. The phase space information may be completely erased by increasing the coupling to the environment. The coherence loss of the Su(2)-state is investigated via the Husimi Wehrl entropy. If the effects of the detuning parameter or/and of the Kerr-like medium are combined with the damping effect, the damping effect of the coupling to the environment may be weaken, and the Wehrl entropy is delayed to reach its steady-state value. At the steady-state value, the phase space information and the coherence are quickly lost.
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.
1994-01-01
The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. academic librarians and technical information specialists as information intermediaries.
Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.
1994-01-01
The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. aerospace industry librarians and technical information specialists as information intermediaries.
Tada, T.; Cho, I.; Shinozaki, Y.
2005-12-01
We have invented a Two-Radius (TR) circular array method of microtremor exploration, an algorithm that enables to estimate phase velocities of Love waves by analyzing horizontal-component records of microtremors that are obtained with an array of seismic sensors placed around circumferences of two different radii. The data recording may be done either simultaneously around the two circles or in two separate sessions with sensors distributed around each circle. Both Rayleigh and Love waves are present in the horizontal components of microtremors, but in the data processing of our TR method, all information on the Rayleigh waves ends up cancelled out, and information on the Love waves alone are left to be analyzed. Also, unlike the popularly used frequency-wavenumber spectral (F-K) method, our TR method does not resolve individual plane-wave components arriving from different directions and analyze their "vector" phase velocities, but instead directly evaluates their "scalar" phase velocities --- phase velocities that contain no information on the arrival direction of waves --- through a mathematical procedure which involves azimuthal averaging. The latter feature leads us to expect that, with our TR method, it is possible to conduct phase velocity analysis with smaller numbers of sensors, with higher stability, and up to longer-wavelength ranges than with the F-K method. With a view to investigating the capabilities and limitations of our TR method in practical implementation to real data, we have deployed circular seismic arrays of different sizes at a test site in Japan where the underground structure is well documented through geophysical exploration. Ten seismic sensors were placed equidistantly around two circumferences, five around each circle, with varying combinations of radii ranging from several meters to several tens of meters, and simultaneous records of microtremors around circles of two different radii were analyzed with our TR method to produce
MOBI-DIC: MOBIle DIssemination of loCal information in Peer-to-Peer Wireless Networks, Phase I
National Aeronautics and Space Administration — Information Technology (IT) is a key element in the successful achievement of NASA's strategic goals. Modern IT tools and techniques have the capability to redefine...
Hively, Lee M.
2014-09-16
Data collected from devices and human condition may be used to forewarn of critical events such as machine/structural failure or events from brain/heart wave data stroke. By monitoring the data, and determining what values are indicative of a failure forewarning, one can provide adequate notice of the impending failure in order to take preventive measures. This disclosure teaches a computer-based method to convert dynamical numeric data representing physical objects (unstructured data) into discrete-phase-space states, and hence into a graph (structured data) for extraction of condition change.
Directory of Open Access Journals (Sweden)
Morag Farquhar
Full Text Available Breathlessness is a common symptom of advanced disease placing a huge burden on patients, health systems and informal carers (families and friends providing daily help and support. It causes distress and isolation. Carers provide complex personal, practical and emotional support yet often feel ill-prepared to care. They lack knowledge and confidence in their caring role. The need to educate carers and families about breathlessness is established, yet we lack robustly developed carer-targeted educational interventions to meet their needs.We conducted a qualitative interview study with twenty five purposively-sampled patient-carer dyads living with breathlessness in advanced disease (half living with advanced cancer and half with advanced chronic obstructive pulmonary disease (COPD. We sought to identify carers' educational needs (including what they wanted to learn about and explore differences by diagnostic group in order to inform an educational intervention for carers of patients with breathlessness in advanced disease.There was a strong desire among carers for an educational intervention on breathlessness. Six key topics emerged as salient for them: 1 understanding breathlessness, 2 managing anxiety, panic and breathlessness, 3 managing infections, 4 keeping active, 5 living positively and 6 knowing what to expect in the future. A cross-cutting theme was relationship management: there were tensions within dyads resulting from mismatched expectations related to most topics. Carers felt that knowledge-gains would not only help them to support the patient better, but also help them to manage their own frustrations, anxieties, and quality of life. Different drivers for education need were identified by diagnostic group, possibly related to differences in caring role duration and resulting impacts.Meeting the educational needs of carers requires robustly developed and evaluated interventions. This study provides the evidence-base for the content
Townley, Charles T.
Under a grant from the Bureau of Libraries and Learning Resources of the United States Office of Education, the National Indian Education Association (NIEA) implemented a Library Project to identify library and information needs of Indian people and to establish, operate, and evaluate three demonstration sites. During this reporting period,…
Energy Technology Data Exchange (ETDEWEB)
Cerna, P.A.; Conner, W.M.; Curtis, L.M. [and others
1995-06-01
The Federal Emergency Management Information System (FEMIS) is an emergency management planning and analysis tool that is being developed under the direction of the U.S. Army Chemical Biological Defense Command. The FEMIS System Administration Guide defines FEMIS hardware and software requirements and gives instructions for installing the FEMIS software package.
Aligning Business Process Quality and Information System Quality
Heinrich, Robert
2013-01-01
Business processes and information systems mutually affect each other in non-trivial ways. Frequently, the business process design and the information system design are not well aligned. This means that business processes are designed without taking the information system impact into account, and vice versa. Missing alignment at design time often results in quality problems at runtime, such as large response times of information systems, large process execution times, overloaded information s...
International Nuclear Information System (INIS)
Hofer, K.; Zehnder, P.; Galperin, A.
1994-01-01
This report deals with a conceptual design of an integrated information management system, called PSI-IRIS, as needed to assist the analysts for reactor safety related investigations on Swiss nuclear power plants within the project STARS. Performing complicated engineering analyses of an NPP requires storage and manipulation of a large amount of information, both data and knowledge. This information is characterized by its multi-disciplinary nature, complexity, and diversity. The problems caused by inefficient and lengthy manual operations involving the data flow management within the framework of the safety related analysis of an NPP, can be solved by applying computer aided engineering (CAE) principles. These principles are the basis for the design of the integrated information management system PSI-IRIS presented in this report. The basic idea is to create a computerized environment, which includes both database and functional capabilities. The database of the PSI-IRIS consists of two parts, an NPP generic database (GDB) and a collection of analysis results (CASE L IB). The GDB includes all technical plant data and information needed to generate input decks for all computer codes utilized within the STARS project. The CASE L IB storage contains the accumulated knowledge, input decks, and result files of the NPP transient analyses. Considerations and analysis of the data types and the required data manipulation capabilities as well as operational requirements resulted in the choice of an object-oriented database management system (OODBMS) as a development platform for solving the software engineering problems. Several advantages of OODBMS's over conventional relational database management systems were found of crucial importance, especially providing the necessary flexibility for different data types and the potential for extensibility. (author) 15 figs., tabs., 20 refs
Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing
2016-08-01
A novel image encryption system based on double random phase encoding (DRPE) and RSA public-key algorithm is proposed. The main characteristic of the system is that each encryption process produces a new decryption key (even for the same plaintext), thus the encryption system conforms to the feature of the one-time pad (OTP) cryptography. The other characteristic of the system is the use of fingerprint key. Only with the rightful authorization will the true decryption be obtained, otherwise the decryption will result in noisy images. So the proposed system can be used to determine whether the ciphertext is falsified by attackers. In addition, the system conforms to the basic agreement of asymmetric cryptosystem (ACS) due to the combination with the RSA public-key algorithm. The simulation results show that the encryption scheme has high robustness against the existing attacks.
Energy Technology Data Exchange (ETDEWEB)
Espinoza, J. Jr.; Dean, C.D.; Armstrong, H.M. [and others
1997-06-01
The Geographic Information System-Transportation (GIS-T) ISTEA Management Systems Server Net Prototype Pooled Fund Study represents the first national cooperative effort in the transportation industry to address the management and monitoring systems as well as the statewide and metropolitan transportation planning requirements of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA). The Study was initiated in November 1993 through the Alliance for Transportation Research and under the leadership of the New Mexico State Highway and Transportation Department. Sandia National Laboratories, an Alliance partner, and Geographic Paradigm Computing. Inc. provided technical leadership for the project. In 1992, the Alliance for Transportation Research, the New Mexico State Highway and Transportation Department, Sandia National Laboratories, and Geographic Paradigm Computing, Inc., proposed a comprehensive research agenda for GIS-T. That program outlined a national effort to synthesize new transportation policy initiatives (e.g., management systems and Intelligent Transportation Systems) with the GIS-T server net ideas contained in the NCHRP project {open_quotes}Adaptation of GIS to Transportation{close_quotes}. After much consultation with state, federal, and private interests, a project proposal based on this agenda was prepared and resulted in this Study. The general objective of the Study was to develop GIS-T server net prototypes supporting the ISTEA requirements for transportation planning and management and monitoring systems. This objective can be further qualified to: (1) Create integrated information system architectures and design requirements encompassing transportation planning activities and data. (2) Encourage the development of functional GIS-T server net prototypes. (3) Demonstrate multiple information systems implemented in a server net environment.
Raphaelis, Silvia; Mayer, Hanna; Ott, Stefan; Mueller, Michael D; Steiner, Enikö; Joura, Elmar; Senn, Beate
2017-07-01
To determine whether written information and/or counseling based on the WOMAN-PRO II Program decreases symptom prevalence in women with vulvar neoplasia by a clinically relevant degree, and to explore the differences between the 2 interventions in symptom prevalence, symptom distress prevalence, and symptom experience. A multicenter randomized controlled parallel-group phase II trial with 2 interventions provided to patients after the initial diagnosis was performed in Austria and Switzerland. Women randomized to written information received a predefined set of leaflets concerning wound care and available healthcare services. Women allocated to counseling were additionally provided with 5 consultations by an Advanced Practice Nurse (APN) between the initial diagnosis and 6months post-surgery that focused on symptom management, utilization of healthcare services, and health-related decision-making. Symptom outcomes were simultaneously measured 5 times to the counseling time points. A total of 49 women with vulvar neoplasia participated in the study. Symptom prevalence decreased in women with counseling by a clinically relevant degree, but not in women with written information. Sporadically, significant differences between the 2 interventions could be observed in individual items, but not in the total scales or subscales of the symptom outcomes. The results indicate that counseling may reduce symptom prevalence in women with vulvar neoplasia by a clinically relevant extent. The observed group differences between the 2 interventions slightly favor counseling over written information. The results justify testing the benefit of counseling thoroughly in a comparative phase III trial. Copyright © 2017 Elsevier Inc. All rights reserved.
Weber, Thomas; Pelzer, Georg; Bayer, Florian; Horn, Florian; Rieger, Jens; Ritter, André; Zang, Andrea; Durst, Jürgen; Anton, Gisela; Michel, Thilo
2013-07-29
A novel information retrieval algorithm for X-ray grating-based phase-contrast imaging based on the deconvolution of the object and the reference phase stepping curve (PSC) as proposed by Modregger et al. was investigated in this paper. We applied the method for the first time on data obtained with a polychromatic spectrum and compared the results to those, received by applying the commonly used method, based on a Fourier analysis. We confirmed the expectation, that both methods deliver the same results for the absorption and the differential phase image. For the darkfield image, a mean contrast-to-noise ratio (CNR) increase by a factor of 1.17 using the new method was found. Furthermore, the dose saving potential was estimated for the deconvolution method experimentally. It is found, that for the conventional method a dose which is higher by a factor of 1.66 is needed to obtain a similar CNR value compared to the novel method. A further analysis of the data revealed, that the improvement in CNR and dose efficiency is due to the superior background noise properties of the deconvolution method, but at the cost of comparability between measurements at different applied dose values, as the mean value becomes dependent on the photon statistics used.
International Nuclear Information System (INIS)
Mizuno, Yuko; Ninokata, Hisashi; Finnicum, David J.
2005-01-01
In this study, a probabilistic risk assessment (PRA) for the International Reactor Innovative and Secure (IRIS) has been generated to address two key areas as a part of the effort for the pre-application licensing of the IRIS design. First, the IRIS PRA is supporting the evaluation of IRIS design by providing design insights as well as a solid risk basis for the pre-licensing evaluation of the IRIS design. Second, the current PRA task is beginning the preparation of the more complete PRA analyses and documentation that will be required for Design Certification. The initial IRIS PRA is an at-power, Level-1 PRA for internal events that focuses on the evaluation of the IRIS design features to support the risk-informed design of IRIS by application of the PRA insights and the risk information to the design. To accomplish the evaluation, a reasonably complete Level-1 PRA model has been developed. The use of PRA in the early stages of the design has allowed a selection of design and performance features and an optimization of the design of several systems to reduce the potential for events that could lead to core damage via both enhanced prevention and mitigation of challenges. As a result, the total core damage frequency for internal events for the IRIS design has been calculated as 1.2x10 -8 per year
International Nuclear Information System (INIS)
Magdeleine, S.
2009-11-01
This work is a part of a long term project that aims at using two-phase Direct Numerical Simulation (DNS) in order to give information to averaged models. For now, it is limited to isothermal bubbly flows with no phase change. It could be subdivided in two parts: Firstly, theoretical developments are made in order to build an equivalent of Large Eddy Simulation (LES) for two phase flows called Interfaces and Sub-grid Scales (ISS). After the implementation of the ISS model in our code called Trio U , a set of various cases is used to validate this model. Then, special test are made in order to optimize the model for our particular bubbly flows. Thus we showed the capacity of the ISS model to produce a cheap pertinent solution. Secondly, we use the ISS model to perform simulations of bubbly flows in column. Results of these simulations are averaged to obtain quantities that appear in mass, momentum and interfacial area density balances. Thus, we processed to an a priori test of a complete one dimensional averaged model.We showed that this model predicts well the simplest flows (laminar and monodisperse). Moreover, the hypothesis of one pressure, which is often made in averaged model like CATHARE, NEPTUNE and RELAP5, is satisfied in such flows. At the opposite, without a polydisperse model, the drag is over-predicted and the uncorrelated A i flux needs a closure law. Finally, we showed that in turbulent flows, fluctuations of velocity and pressure in the liquid phase are not represented by the tested averaged model. (author)
Liu, Chien-Tsai; Yang, Pei-Tun; Yeh, Yu-Ting; Wang, Bin-Long
2006-02-01
To investigate the impacts of the first phase of Taiwan's Bureau of National Health Insurance (TBNHI) smart card project on existing hospital information systems. TBNHI has launched a nationwide project for replacement of its paper-based health insurance cards by smart cards (or NHI-IC cards) since November 1999. The NHI-IC cards have been used since 1 July 2003, and they have fully replaced the paper-based cards since 1 January 2004. Hospitals must support the cards in order to provide medical services for insured patients. We made a comprehensive study of the current phase of the NHI-IC card system, and conducted a questionnaire survey (from 1 October to 30 November, 2003) to investigate the impacts of NHI-IC cards on the existing hospital information systems. A questionnaire was distributed by mail to 479 hospitals, including 23 medical centers, 71 regional hospitals, and 355 district hospitals. The returned questionnaires were also collected by prepaid mail. The questionnaire return rates of the medical centers, regional hospitals and district hospitals were 39.1, 29.6 and 20.9%, respectively. In phase 1 of the project, the average number of card readers purchased per medical center, regional hospital, and district hospital were 202, 45 and 10, respectively. The average person-days for the enhancement of existing information systems of a medical center, regional hospital and district hospital were 175, 74 and 58, respectively. Three months after using the NHI-IC cards most hospitals (60.6%) experienced prolonged service time for their patients due to more interruptions caused mainly by: (1) impairment of the NHI-IC cards (31.2%), (2) failure in authentication of the SAMs (17.0%), (3) malfunction in card readers (15.3%) and (4) problems with interfaces between the card readers and hospital information systems (15.8%). The overall hospital satisfaction on the 5-point Likert scale was 2.86. Although most hospitals were OK with the project, there was about 22
Energy Technology Data Exchange (ETDEWEB)
Baggio, Marco [Institute for Theoretical Physics, KU Leuven,Celestijnenlaan 200D, B-3001 Leuven (Belgium); Niarchos, Vasilis [Department of Mathematical Sciences and Center for Particle Theory, Durham University,South Road, Durham, DH1 3LE (United Kingdom); Papadodimas, Kyriakos [Theory Group, Physics Department, CERN,CH-1211 Geneva 23 (Switzerland); Van Swinderen Institute for Particle Physics and Gravity, University of Groningen,Nijenborgh 4, 9747 AG Groningen (Netherlands)
2017-04-11
When continuous parameters in a QFT are varied adiabatically, quantum states typically undergo mixing — a phenomenon characterized by the Berry phase. We initiate a systematic analysis of the Berry phase in QFT using standard quantum mechanics methods. We show that a non-trivial Berry phase appears in many familiar QFTs. We study a variety of examples including free electromagnetism with a theta angle, and certain supersymmetric QFTs in two and four spacetime dimensions. We also argue that a large class of QFTs with rich Berry properties is provided by CFTs with non-trivial conformal manifolds. Using the operator-state correspondence we demonstrate in this case that the Berry connection is equivalent to the connection on the conformal manifold derived previously in conformal perturbation theory. In the special case of chiral primary states in 2d N=(2,2) and 4d N=2 SCFTs the Berry phase is governed by the tt{sup ∗} equations. We present a technically useful rederivation of these equations using quantum mechanics methods.
Directory of Open Access Journals (Sweden)
Ramon Abilio
2015-08-01
Full Text Available Systematic Literature Review (SLR is a means to synthesize relevant and high quality studies related to a specific topic or research questions. In the Primary Selection stage of an SLR, the selection of studies is usually performed manually by reading title, abstract and keywords of each study. In the last years, the number of published scientific studies has grown increasing the effort to perform this sort of reviews. In this paper, we proposed strategies to detect non-papers and duplicated references in results exported by search engines, and strategies to rank the references in decreasing order of importance for an SLR, regarding the terms in the search string. These strategies are based on Information Retrieval techniques. We implemented the strategies and carried out an experimental evaluation of their applicability using two real datasets. As results, the strategy to detect non-papers presented 100% of precision and 50% of recall; the strategy to detect duplicates detected more duplicates than the manual inspection; and one of the strategies to rank relevant references presented 50% of precision and 80% of recall. Therefore, the results show that the proposed strategies can minimize the effort in the Primary Selection stage of an SLR.
Energy Technology Data Exchange (ETDEWEB)
Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Szecsody, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhong, Lirong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thomle, Jonathan N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Timothy C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2014-09-01
Uranium is present in the vadose zone at the Hanford Central Plateau and is of concern for protection of groundwater. The Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau identified gas-phase treatment and geochemical manipulation as potentially effective treatment approaches for uranium and technetium in the Hanford Central Plateau vadose zone. Based on laboratory evaluation, use of ammonia vapor was selected as the most promising uranium treatment candidate for further development and field testing. While laboratory tests have shown that ammonia treatment effectively reduces the mobility of uranium, additional information is needed to enable deployment of this technology for remediation. Of importance for field applications are aspects of the technology associated with effective distribution of ammonia to a targeted treatment zone, understanding the fate of injected ammonia and its impact on subsurface conditions, and identifying effective monitoring approaches. In addition, information is needed to select equipment and operational parameters for a field design. As part of development efforts for the ammonia technology for remediation of vadose zone uranium contamination, field scale-up issues were identified and have been addressed through a series of laboratory and modeling efforts. This report presents a conceptual description for field application of the ammonia treatment process, engineering calculations to support treatment design, ammonia transport information, field application monitoring approaches, and a discussion of processes affecting the fate of ammonia in the subsurface. The report compiles this information from previous publications and from recent research and development activities. The intent of this report is to provide technical information about these scale-up elements to support the design and operation of a field test for the ammonia treatment technology.
International Nuclear Information System (INIS)
Zhou Yunlong; Chen Fei; Sun Bin
2008-01-01
Based on the characteristic that wavelet packet transform image can be decomposed by different scales, a flow regime identification method based on image wavelet packet information entropy feature and genetic neural network was proposed. Gas-liquid two-phase flow images were captured by digital high speed video systems in horizontal pipe. The information entropy feature from transformation coefficients were extracted using image processing techniques and multi-resolution analysis. The genetic neural network was trained using those eigenvectors, which was reduced by the principal component analysis, as flow regime samples, and the flow regime intelligent identification was realized. The test result showed that image wavelet packet information entropy feature could excellently reflect the difference between seven typical flow regimes, and the genetic neural network with genetic algorithm and BP algorithm merits were with the characteristics of fast convergence for simulation and avoidance of local minimum. The recognition possibility of the network could reach up to about 100%, and a new and effective method was presented for on-line flow regime. (authors)
Guo, Y. N.; Tian, Q. L.; Mo, Y. F.; Zhang, G. L.; Zeng, K.
2018-04-01
In this paper, we have investigated the preservation of quantum Fisher information (QFI) of a single-qubit system coupled to a common zero temperature reservoir through the addition of noninteracting qubits. The results show that, the QFI is completely protected in both Markovian and non-Markovian regimes by increasing the number of additional qubits. Besides, the phenomena of QFI display monotonic decay or non-monotonic with revival oscillations depending on the number of additional qubits N - 1 in a common dissipative reservoir. If N revival oscillations. Moreover, we extend this model to investigate the effect of additional qubits and the initial conditions of the system on the geometric phase (GP). It is found that, the robustness of GP against the dissipative reservoir has been demonstrated by increasing gradually the number of additional qubits N - 1. Besides, the GP is sensitive to the initial parameter 𝜃, and possesses symmetric in a range regime [0,2 π].
Stanga, C.; Spinelli, C.; Brumana, R.; Oreni, D.; Valente, R.; Banfi, F.
2017-08-01
This essay describes the combination of 3D solutions and software techniques with traditional studies and researches in order to achieve an integrated digital documentation between performed surveys, collected data, and historical research. The approach of this study is based on the comparison of survey data with historical research, and interpretations deduced from a data cross-check between the two mentioned sources. The case study is the Basilica of S. Ambrogio in Milan, one of the greatest monuments in the city, a pillar of the Christianity and of the History of Architecture. It is characterized by a complex stratification of phases of restoration and transformation. Rediscovering the great richness of the traditional architectural notebook, which collected surveys and data, this research aims to realize a virtual notebook, based on a 3D model that supports the dissemination of the collected information. It can potentially be understandable and accessible by anyone through the development of a mobile app. The 3D model was used to explore the different historical phases, starting from the recent layers to the oldest ones, through a virtual subtraction process, following the methods of Archaeology of Architecture. Its components can be imported into parametric software and recognized both in their morphological and typological aspects. It is based on the concept of LoD and ReverseLoD in order to fit the accuracy required by each step of the research.
Directory of Open Access Journals (Sweden)
C. Stanga
2017-08-01
Full Text Available This essay describes the combination of 3D solutions and software techniques with traditional studies and researches in order to achieve an integrated digital documentation between performed surveys, collected data, and historical research. The approach of this study is based on the comparison of survey data with historical research, and interpretations deduced from a data cross-check between the two mentioned sources. The case study is the Basilica of S. Ambrogio in Milan, one of the greatest monuments in the city, a pillar of the Christianity and of the History of Architecture. It is characterized by a complex stratification of phases of restoration and transformation. Rediscovering the great richness of the traditional architectural notebook, which collected surveys and data, this research aims to realize a virtual notebook, based on a 3D model that supports the dissemination of the collected information. It can potentially be understandable and accessible by anyone through the development of a mobile app. The 3D model was used to explore the different historical phases, starting from the recent layers to the oldest ones, through a virtual subtraction process, following the methods of Archaeology of Architecture. Its components can be imported into parametric software and recognized both in their morphological and typological aspects. It is based on the concept of LoD and ReverseLoD in order to fit the accuracy required by each step of the research.
webXice: an Infrastructure for Information Commerce on the WWW
Wombacher, Andreas; Kostaki, Paraskevi; Aberer, Karl
Systems for information commerce on the WWW have to support flexible business models if they should be able to cover a wide range of requirements imposed by the different types of information businesses. This leads to non-trivial functional and security requirements both on the provider and consumer
Phase structure of lattice QCD for general number of flavors
International Nuclear Information System (INIS)
Iwasaki, Y.; Kanaya, K.; Yoshie, T.; Kaya, S.; Sakai, S.
2004-01-01
We investigate the phase structure of lattice QCD for the general number of flavors in the parameter space of gauge coupling constant and quark mass, employing the one-plaquette gauge action and the standard Wilson quark action. Performing a series of simulations for the number of flavors N F =6-360 with degenerate-mass quarks, we find that when N F ≥7 there is a line of a bulk first order phase transition between the confined phase and a deconfined phase at a finite current quark mass in the strong coupling region and the intermediate coupling region. The massless quark line exists only in the deconfined phase. Based on these numerical results in the strong coupling limit and in the intermediate coupling region, we propose the following phase structure, depending on the number of flavors whose masses are less than Λ d which is the physical scale characterizing the phase transition in the weak coupling region: When N F ≥17, there is only a trivial IR fixed point and therefore the theory in the continuum limit is free. On the other hand, when 16≥N F ≥7, there is a nontrivial IR fixed point and therefore the theory is nontrivial with anomalous dimensions, however, without quark confinement. Theories which satisfy both quark confinement and spontaneous chiral symmetry breaking in the continuum limit exist only for N F ≤6
International Nuclear Information System (INIS)
Haase, R.W.; Butler, P.H.
1985-01-01
We give tables of algebraic formulas for some nontrivial 6j symbols and 3jm symbols of the unitary groups. The tables demonstrate that the building-up method can be used successfully to obtain the rank dependence of unitary group j and jm symbols. To emphasize the rank-dependent nature of this calculation, we have employed the composite Young tableaux notation (or back-to-back notation) to label the unitary group irreps. In using this notation, the transpose conjugate symmetry of the corresponding composite Young diagram leads to a new symmetry of the unitary group 6j and 3jm symbols. The transposition of the groups U/sub m/ and U/sub n/ gives rise to a further symmetry of the 3jm symbols of U/sub m/n contains U/sub m/ x U/sub n/
Plasmon Geometric Phase and Plasmon Hall Shift
Shi, Li-kun; Song, Justin C. W.
2018-04-01
The collective plasmonic modes of a metal comprise a simple pattern of oscillating charge density that yields enhanced light-matter interaction. Here we unveil that beneath this familiar facade plasmons possess a hidden internal structure that fundamentally alters its dynamics. In particular, we find that metals with nonzero Hall conductivity host plasmons with an intricate current density configuration that sharply departs from that of ordinary zero Hall conductivity metals. This nontrivial internal structure dramatically enriches the dynamics of plasmon propagation, enabling plasmon wave packets to acquire geometric phases as they scatter. At boundaries, these phases accumulate allowing plasmon waves that reflect off to experience a nonreciprocal parallel shift. This plasmon Hall shift, tunable by Hall conductivity as well as plasmon wavelength, displaces the incident and reflected plasmon trajectories and can be readily probed by near-field photonics techniques. Anomalous plasmon geometric phases dramatically enrich the nanophotonics toolbox, and yield radical new means for directing plasmonic beams.
Friction forces on phase transition fronts
International Nuclear Information System (INIS)
Mégevand, Ariel
2013-01-01
In cosmological first-order phase transitions, the microscopic interaction of the phase transition fronts with non-equilibrium plasma particles manifests itself macroscopically as friction forces. In general, it is a nontrivial problem to compute these forces, and only two limits have been studied, namely, that of very slow walls and, more recently, ultra-relativistic walls which run away. In this paper we consider ultra-relativistic velocities and show that stationary solutions still exist when the parameters allow the existence of runaway walls. Hence, we discuss the necessary and sufficient conditions for the fronts to actually run away. We also propose a phenomenological model for the friction, which interpolates between the non-relativistic and ultra-relativistic values. Thus, the friction depends on two friction coefficients which can be calculated for specific models. We then study the velocity of phase transition fronts as a function of the friction parameters, the thermodynamic parameters, and the amount of supercooling
Phase diagram and topological phases in the triangular lattice Kitaev-Hubbard model
Li, Kai; Yu, Shun-Li; Gu, Zhao-Long; Li, Jian-Xin
2016-09-01
We study the half-filled Hubbard model on a triangular lattice with spin-dependent Kitaev-like hopping. Using the variational cluster approach, we identify five phases: a metallic phase, a non-coplanar chiral magnetic order, a 120° magnetic order, a nonmagnetic insulator (NMI), and an interacting Chern insulator (CI) with a nonzero Chern number. The transition from CI to NMI is characterized by the change of the charge gap from an indirect band gap to a direct Mott gap. Based on the slave-rotor mean-field theory, the NMI phase is further suggested to be a gapless Mott insulator with a spinon Fermi surface or a fractionalized CI with nontrivial spinon topology, depending on the strength of the Kitaev-like hopping. Our work highlights the rising field in which interesting phases emerge from the interplay between band topology and Mott physics.
Symmetry protected topological Luttinger liquids and the phase transition between them
Energy Technology Data Exchange (ETDEWEB)
None
2018-01-01
We show that a doped spin-1/2 ladder with antiferromagnetic intra-chain and ferromagnetic inter-chain coupling is a symmetry protected topologically non-trivial Luttinger liquid. Turning on a large easy-plane spin anisotropy drives the system to a topologically-trivial Luttinger liquid. Both phases have full spin gaps and exhibit power-law superconducting pair correlation. The Cooper pair symmetry is singlet $d_{xy}$ in the non-trivial phase and triplet $S_z=0$ in the trivial phase. The topologically non-trivial Luttinger liquid exhibits gapless spin excitations in the presence of a boundary, and it has no non-interacting or mean-field theory analog even when the fluctuating phase in the charge sector is pinned. As a function of the strength of spin anisotropy there is a topological phase transition upon which the spin gap closes. We speculate these Luttinger liquids are relevant to the superconductivity in metalized integer spin ladders or chains.
Anomalous phase shift in a twisted quantum loop
International Nuclear Information System (INIS)
Taira, Hisao; Shima, Hiroyuki
2010-01-01
The coherent motion of electrons in a twisted quantum ring is considered to explore the effect of torsion inherent to the ring. Internal torsion of the ring composed of helical atomic configuration yields a non-trivial quantum phase shift in the electrons' eigenstates. This torsion-induced phase shift causes novel kinds of persistent current flow and an Aharonov-Bohm-like conductance oscillation. The two phenomena can occur even when no magnetic flux penetrates inside the twisted ring, thus being in complete contrast with the counterparts observed in untwisted rings.
Effects of phase transition induced density fluctuations on pulser dynamics
International Nuclear Information System (INIS)
Bagchi, Partha; Das, Arpan; Srivastava, Ajit M.; Layek, Biswanath
2016-01-01
We show that density fluctuations during phase transitions in pulsar cores may have non-trivial effects on pulsar timings, and may also possibly account for glitches and anti-glitches. These density fluctuations invariably lead to non-zero off-diagonal components of the moment of inertia, leading to transient wobbling of star. Thus, accurate measurements of pulsar timing and intensity modulations (from wobbling) may be used to identify the specific pattern of density fluctuations, hence the particular phase transition, occurring inside the pulsar core. Changes in quadrupole moment from rapidly evolving density fluctuations during the transition, with very short time scales, may provide a new source for gravitational waves. (author)
Low energy scattering with a nontrivial pion
International Nuclear Information System (INIS)
Fariborz, Amir H.; Jora, Renata; Schechter, Joseph
2007-01-01
An earlier calculation in a generalized linear sigma model showed that the well-known current algebra formula for low energy pion-pion scattering held even though the massless Nambu Goldstone pion contained a small admixture of a two-quark two-antiquark field. Here we turn on the pion mass and note that the current algebra formula no longer holds exactly. We discuss this small deviation and also study the effects of a SU(3) symmetric quark mass type term on the masses and mixings of the eight SU(3) multiplets in the model. We calculate the s-wave scattering lengths, including the beyond current algebra theorem corrections due to the scalar mesons, and observe that the effect of the scalar mesons is to improve the agreement with experiment. In the process, we uncover the way in which linear sigma models give controlled corrections (due to the presence of scalar mesons) to the current algebra scattering formula. Such a feature is commonly thought to exist only in the nonlinear sigma model approach
Phase diagram and quench dynamics of the cluster-XY spin chain.
Montes, Sebastián; Hamma, Alioscia
2012-08-01
We study the complete phase space and the quench dynamics of an exactly solvable spin chain, the cluster-XY model. In this chain, the cluster term and the XY couplings compete to give a rich phase diagram. The phase diagram is studied by means of the quantum geometric tensor. We study the time evolution of the system after a critical quantum quench using the Loschmidt echo. The structure of the revivals after critical quantum quenches presents a nontrivial behavior depending on the phase of the initial state and the critical point.
Energy Technology Data Exchange (ETDEWEB)
Kang, S; Kim, D; Kim, T; Park, S; Shin, D; Kim, K; Cho, M; Suh, T [Department of Biomedical Engineering and Research Institute of Biomedical Engineering, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States)
2016-06-15
Purpose: To propose a simple and effective cost value function to search optimal planning phase (gating window) and demonstrated its feasibility for respiratory correlated radiation therapy. Methods: We acquired 4DCT of 10 phases for 10 lung patients who have tumor located near OARs such as esophagus, heart, and spinal cord (i.e., central lung cancer patients). A simplified mathematical optimization function was established by using overlap volume histogram (OVH) between the target and organ at risk (OAR) at each phase and the tolerance dose of selected OARs to achieve surrounding OARs dose-sparing. For all patients and all phases, delineation of the target volume and selected OARs (esophagus, heart, and spinal cord) was performed (by one observer to avoid inter-observer variation), then cost values were calculated for all phases. After the breathing phases were ranked according to cost value function, the relationship between score and dose distribution at highest and lowest cost value phases were evaluated by comparing the mean/max dose. Results: A simplified mathematical cost value function showed noticeable difference from phase to phase, implying it is possible to find optimal phases for gating window. The lowest cost value which may result in lower mean/max dose to OARs was distributed at various phases for all patients. The mean doses of the OARs significantly decreased about 10% with statistical significance for all 3 OARs at the phase with the lowest cost value. Also, the max doses of the OARs were decreased about 2∼5% at the phase with the lowest cost value compared to the phase with the highest cost value. Conclusion: It is demonstrated that optimal phases (in dose distribution perspective) for gating window could exist differently through each patient and the proposed cost value function can be a useful tool for determining such phases without performing dose optimization calculations. This research was supported by the Mid-career Researcher Program
Oertel, Peter; Bergmann, Andreas; Fischer, Sina; Trefz, Phillip; Küntzel, Anne; Reinhold, Petra; Köhler, Heike; Schubert, Jochen K; Miekisch, Wolfram
2018-05-14
Volatile organic compounds (VOCs) emitted from in vitro cultures may reveal information on species and metabolism. Owing to low nmol L -1 concentration ranges, pre-concentration techniques are required for gas chromatography-mass spectrometry (GC-MS) based analyses. This study was intended to compare the efficiency of established micro-extraction techniques - solid-phase micro-extraction (SPME) and needle-trap micro-extraction (NTME) - for the analysis of complex VOC patterns. For SPME, a 75 μm Carboxen®/polydimethylsiloxane fiber was used. The NTME needle was packed with divinylbenzene, Carbopack X and Carboxen 1000. The headspace was sampled bi-directionally. Seventy-two VOCs were calibrated by reference standard mixtures in the range of 0.041-62.24 nmol L -1 by means of GC-MS. Both pre-concentration methods were applied to profile VOCs from cultures of Mycobacterium avium ssp. paratuberculosis. Limits of detection ranged from 0.004 to 3.93 nmol L -1 (median = 0.030 nmol L -1 ) for NTME and from 0.001 to 5.684 nmol L -1 (median = 0.043 nmol L -1 ) for SPME. NTME showed advantages in assessing polar compounds such as alcohols. SPME showed advantages in reproducibility but disadvantages in sensitivity for N-containing compounds. Micro-extraction techniques such as SPME and NTME are well suited for trace VOC profiling over cultures if the limitations of each technique is taken into account. Copyright © 2018 John Wiley & Sons, Ltd.
International Nuclear Information System (INIS)
Abal'osheva, I.; Lewandowski, S.J.
2004-01-01
It is shown that the inclusion of junctions characterized by non-sinusoidal current - phase relationship in the systems composed of multiple Josephson junctions - results in the appearance of additional system phase states. Numerical simulations and stability considerations confirm that those phase states can be realized in practice. Moreover, spontaneous formation of the grain boundary junctions in high-T c superconductors with non-trivial current-phase relations due to the d-wave symmetry of the order parameter is probable. Switching between the phase states of multiple grain boundary junction systems can lead to additional 1/f noise in high-T c superconductors. (author)
Fourier phasing with phase-uncertain mask
International Nuclear Information System (INIS)
Fannjiang, Albert; Liao, Wenjing
2013-01-01
Fourier phasing is the problem of retrieving Fourier phase information from Fourier intensity data. The standard Fourier phase retrieval (without a mask) is known to have many solutions which cause the standard phasing algorithms to stagnate and produce wrong or inaccurate solutions. In this paper Fourier phase retrieval is carried out with the introduction of a randomly fabricated mask in measurement and reconstruction. Highly probable uniqueness of solution, up to a global phase, was previously proved with exact knowledge of the mask. Here the uniqueness result is extended to the case where only rough information about the mask’s phases is assumed. The exponential probability bound for uniqueness is given in terms of the uncertainty-to-diversity ratio of the unknown mask. New phasing algorithms alternating between the object update and the mask update are systematically tested and demonstrated to have the capability of recovering both the object and the mask (within the object support) simultaneously, consistent with the uniqueness result. Phasing with a phase-uncertain mask is shown to be robust with respect to the correlation in the mask as well as the Gaussian and Poisson noises. (paper)
Energy Technology Data Exchange (ETDEWEB)
Nutt, M.; Nuclear Engineering Division
2010-05-25
The activity of Phase I of the Waste Management Working Group under the United States - Japan Joint Nuclear Energy Action Plan started in 2007. The US-Japan JNEAP is a bilateral collaborative framework to support the global implementation of safe, secure, and sustainable, nuclear fuel cycles (referred to in this document as fuel cycles). The Waste Management Working Group was established by strong interest of both parties, which arise from the recognition that development and optimization of waste management and disposal system(s) are central issues of the present and future nuclear fuel cycles. This report summarizes the activity of the Waste Management Working Group that focused on consolidation of the existing technical basis between the U.S. and Japan and the joint development of a plan for future collaborative activities. Firstly, the political/regulatory frameworks related to nuclear fuel cycles in both countries were reviewed. The various advanced fuel cycle scenarios that have been considered in both countries were then surveyed and summarized. The working group established the working reference scenario for the future cooperative activity that corresponds to a fuel cycle scenario being considered both in Japan and the U.S. This working scenario involves transitioning from a once-through fuel cycle utilizing light water reactors to a one-pass uranium-plutonium fuel recycle in light water reactors to a combination of light water reactors and fast reactors with plutonium, uranium, and minor actinide recycle, ultimately concluding with multiple recycle passes primarily using fast reactors. Considering the scenario, current and future expected waste streams, treatment and inventory were discussed, and the relevant information was summarized. Second, the waste management/disposal system optimization was discussed. Repository system concepts were reviewed, repository design concepts for the various classifications of nuclear waste were summarized, and the factors
International Nuclear Information System (INIS)
Yui, Mikazu; Ishikawa, Hirohisa; Umeki, Hiroyuki; Hioki, Kazumasa; Naito, Morimasa; Makino, Hitoshi; Oda, Chie; Tachi, Yukio; Mitsui, Seiichiro; Shibata, Masahiro; Watanabe, Atsuo; Yoshino, Kyoji; Seo, Toshihiro; Miyamoto, Yoichi; Nutt, Mark; Peters, Mark; Bresee, James; Lesica, Sue; Schwab, Patrick; Gomberg, Steve; Jones, Jay; Halsey, Bill; Marra, John; Vienna, John; Gombert, Drik; McMahon, Kevin; James, Scott; Caporuscio, Florie
2010-05-01
The activity of Phase I of the Waste Management Working Group under the United States - Japan Joint Nuclear Energy Action Plan started in 2007. The US-Japan JNEAP is a bilateral collaborative framework to support the global implementation of safe, secure, and sustainable, nuclear fuel cycles (referred to in this document as fuel cycles). The Waste Management Working Group was established by strong interest of both parties, which arise from the recognition that development and optimization of waste management and disposal system(s) are central issues of the present and future nuclear fuel cycles. This report summarizes the activity of the Waste Management Working Group that focused on consolidation of the existing technical basis between the U.S. and Japan and the joint development of a plan for future collaborative activities. Firstly, the political/regulatory frameworks related to nuclear fuel cycles in both countries were reviewed. The various advanced fuel cycle scenarios that have been considered in both countries were then surveyed and summarized. The working group established the working reference scenario for the future cooperative activity that corresponds to a fuel cycle scenario being considered both in Japan and the U.S. This working scenario involves transitioning from a once-through fuel cycle utilizing light water reactors to a one-pass uranium-plutonium fuel recycle in light water reactors to a combination of light water reactors and fast reactors with plutonium, uranium, and minor actinide recycle, ultimately concluding with multiple recycle passes primarily using fast reactors. Considering the scenario, current and future expected waste streams, treatment and inventory were discussed, and the relevant information was summarized. Second, the waste management/disposal system optimization was discussed. Repository system concepts were reviewed, repository design concepts for the various classifications of nuclear waste were summarized, and the factors
2009-06-01
Trip origin and destination (OD) data plays a crucial role in various transportation activities. This information not : only includes the starting and end points of a trip, but also information that can be obtained through the ability to : track v...
Lee, Ki Hoon; Chung, Suk Bum; Park, Kisoo; Park, Je-Geun
2018-05-01
We investigated the topological property of magnon bands in the collinear magnetic orders of zigzag and stripe phases for the antiferromagnetic honeycomb lattice and identified Berry curvature and symmetry constraints on the magnon band structure. Different symmetries of both zigzag and stripe phases lead to different topological properties, in particular, the magnon bands of the stripe phase being disentangled with a finite Dzyaloshinskii-Moriya (DM) term with nonzero spin Chern number. This is corroborated by calculating the spin Nernst effect. Our study establishes the existence of a nontrivial magnon band topology for all observed collinear antiferromagnetic honeycomb lattices in the presence of the DM term.
Radiation phase of a dipole field
International Nuclear Information System (INIS)
Shunovsky, A.S.
1998-01-01
In the case of a dipole electromagnetic radiation, the operator of the 'radiation phase' is defined. It is shown that this operator has a discrete spectrum with eigenvalues, lying in the segment [0,2π]. Some properties of the radiation phase and polarization are discussed. Seventy years of investigation of the problem of quantum phase led to the conclusion that there is no unique quantum variable, determining universally the measured phase properties of electromagnetic radiation. The operator constructions, describing cosine and sine of the phase, could be different schemes of measurement. This fact has accurately been confirmed by a number of recent experiments. Thus, it seems to be quite plausible that the quantum phase properties of an electromagnetic radiation are determined by interaction photons with a macroscopic detecting device. It is pertinent to ask the following question. Are the quantum phase properties of radiation completely determined by such an interaction or the photons have their own inherent phase properties which might be measured even if they are modified by interaction with a detecting device? The universally recognized fact is that the vacuum state of field is degenerated with respect to phase. If a quantum radiation has its inherent phase properties, it means that the degeneration is taken off in the process of generation which is an interaction of the vacuum field with excited states of atoms or molecules. By virtue of this picture proposed in, what all one can expect is that the inherent quantum phase properties of radiation are completely determined by a source via the conservation laws, describing the generation process. Even in this way, it seems to determine a unique quantum phase of radiation. As a matter of fact, there are two conservation laws, admitting a nontrivial angular dependence
Pinelli, T. E.; Hinnebusch, P. A.; Jaffe, J. M.
1981-01-01
A selected, annotated bibliography of literature citations related to the design and evaluation of STI systems is presented. The use of manual and machine-readable literature searches; the review of numerous books, periodicals reports, and papers; and the selection and annotation of literature citations were required. The bibliography was produced because the information was needed to develop the methodology for the review and evaluation project, and a survey of the literature did not reveal the existence of a single published source of information pertinent to the subject. Approximately 200 citations are classified in four subject areas. The areas include information - general; information systems - design and evaluation, including information products and services; information - use and need; and information - economics.
Bayesian Statistics at Work: the Troublesome Extraction of the CKM Phase {alpha}
Energy Technology Data Exchange (ETDEWEB)
Charles, J. [CPT, Luminy Case 907, F-13288 Marseille Cedex 9 (France); Hoecker, A. [CERN, CH-1211 Geneva 23 (Switzerland); Lacker, H. [TU Dresden, IKTP, D-01062 Dresden (Germany); Le Diberder, F.R. [LAL, CNRS/IN2P3, Universite Paris-Sud 11, Bat. 200, BP 34, F-91898 Orsay Cedex (France); T' Jampens, S. [LAPP, CNRS/IN2P3, Universite de Savoie, 9 Chemin de Bellevue, BP 110, F-74941 Annecy-le-Vieux Cedex (France)
2007-04-15
In Bayesian statistics, one's prior beliefs about underlying model parameters are revised with the information content of observed data from which, using Bayes' rule, a posterior belief is obtained. A non-trivial example taken from the isospin analysis of B {yields} PP (P = {pi} or {rho}) decays in heavy-flavor physics is chosen to illustrate the effect of the naive 'objective' choice of flat priors in a multi- dimensional parameter space in presence of mirror solutions. It is demonstrated that the posterior distribution for the parameter of interest, the phase {alpha}, strongly depends on the choice of the parameterization in which the priors are uniform, and on the validity range in which the (un-normalizable) priors are truncated. We prove that the most probable values found by the Bayesian treatment do not coincide with the explicit analytical solutions, in contrast to the frequentist approach. It is also shown in the appendix that the {alpha} {yields} 0 limit cannot be consistently treated in the Bayesian paradigm, because the latter violates the physical symmetries of the problem. (authors)
Bayesian Statistics at Work: the Troublesome Extraction of the CKM Phase α
International Nuclear Information System (INIS)
Charles, J.; Hoecker, A.; Lacker, H.; Le Diberder, F.R.; T'Jampens, S.
2007-04-01
In Bayesian statistics, one's prior beliefs about underlying model parameters are revised with the information content of observed data from which, using Bayes' rule, a posterior belief is obtained. A non-trivial example taken from the isospin analysis of B → PP (P = π or ρ) decays in heavy-flavor physics is chosen to illustrate the effect of the naive 'objective' choice of flat priors in a multi- dimensional parameter space in presence of mirror solutions. It is demonstrated that the posterior distribution for the parameter of interest, the phase α, strongly depends on the choice of the parameterization in which the priors are uniform, and on the validity range in which the (un-normalizable) priors are truncated. We prove that the most probable values found by the Bayesian treatment do not coincide with the explicit analytical solutions, in contrast to the frequentist approach. It is also shown in the appendix that the α → 0 limit cannot be consistently treated in the Bayesian paradigm, because the latter violates the physical symmetries of the problem. (authors)
International Nuclear Information System (INIS)
Kuipers, J.W.; Thorpe, R.W.
1979-01-01
Problems of numeric data are examined as these relate to the question of possible steps toward implementation of an integrated national information system for DOE. It is proposed that DOE make policy and organization changes in order to centralize and upgrade information management as a particular responsibility for the oversight of DOE-wide information requirements. Eight points to be emphasized in such a program are set forth
Two-phase semilinear free boundary problem with a degenerate phase
Matevosyan, Norayr
2010-10-16
We study minimizers of the energy functional ∫D[{pipe}∇u{pipe}2 + λ(u+)p]dx for p ∈ (0, 1) without any sign restriction on the function u. The distinguished feature of the problem is the lack of nondegeneracy in the negative phase. The main result states that in dimension two the free boundaries Γ+ = ∂{u > 0} ∩ D andΓ- = ∂{u < 0} ∩ D are C1,α-regular, provided 1 - ∈0 < p < 1. The proof is obtained by a careful iteration of the Harnack inequality to obtain a nontrivial growth estimate in the negative phase, compensating for the apriori unknown nondegeneracy. © 2010 Springer-Verlag.
Cho, I.; Tada, T.; Shinozaki, Y.
2005-12-01
We have developed a Centerless Circular Array (CCA) method of microtremor exploration, an algorithm that enables to estimate phase velocities of Rayleigh waves by analyzing vertical-component records of microtremors that are obtained with an array of three or five seismic sensors placed around a circumference. Our CCA method shows a remarkably high performance in long-wavelength ranges because, unlike the frequency-wavenumber spectral method, our method does not resolve individual plane-wave components in the process of identifying phase velocities. Theoretical considerations predict that the resolving power of our CCA method in long-wavelength ranges depends upon the SN ratio, or the ratio of power of the propagating components to that of the non-propagating components (incoherent noise) contained in the records from the seismic array. The applicability of our CCA method to small-sized arrays on the order of several meters in radius has already been confirmed in our earlier work (Cho et al., 2004). We have deployed circular seismic arrays of different sizes at test sites in Japan where the underground structure is well documented through geophysical exploration, and have applied our CCA method to microtremor records to estimate phase velocities of Rayleigh waves. The estimates were then checked against "model" phase velocities that are derived from theoretical calculations. For arrays of 5, 25, 300 and 600 meters in radii, the estimated and model phase velocities demonstrated fine agreement within a broad wavelength range extending from a little larger than 3r (r: the array radius) up to at least 40r, 14r, 42r and 9r, respectively. This demonstrates the applicability of our CCA method to arrays on the order of several to several hundreds of meters in radii, and also illustrates, in a typical way, the markedly high performance of our CCA method in long-wavelength ranges. We have also invented a mathematical model that enables to evaluate the SN ratio in a given
Phases and phase transitions of S=1 bosons
Indian Academy of Sciences (India)
smukerjee
Quantum phases and phase transitions of bosons. Subroto Mukerjee. Dept. of Physics & Centre for Quantum. Information and Quantum Computing (CQIQC). Indian Institute of Science, Bangalore. 77th annual meeting of the IAS, Nov. 20 2011, PRL Ahmedabad ...
Energy Technology Data Exchange (ETDEWEB)
Linville, B.
1989-09-01
This survey was conducted to determine needs of the petroleum industry for information and data on petroleum production technology, including subjects of most interest and most difficult to obtain, and sources being used to acquire such information. Results of the survey will be used in evaluating the Energy Technology Data Exchange and Department of Energy common data base. A selected sample of world petroleum production specialists and petroleum information specialists and other related personnel were surveyed to learn about their problems in retrieving information and data on petroleum production. They were asked what topics and kinds of information are of current interest, what sources they are using to help resolve their technological problems, what petroleum-producing countries are of interest to them, and other related questions.
CrowdPhase: crowdsourcing the phase problem
Energy Technology Data Exchange (ETDEWEB)
Jorda, Julien; Sawaya, Michael R. [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Yeates, Todd O., E-mail: yeates@mbi.ucla.edu [Institute for Genomics and Proteomics, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); Molecular Biology Institute, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States); University of California, 611 Charles Young Drive East, Los Angeles, CA 90095 (United States)
2014-06-01
possible to extract meaningful information in cases where limited resolution might otherwise prevent initial phasing.
CrowdPhase: crowdsourcing the phase problem
International Nuclear Information System (INIS)
Jorda, Julien; Sawaya, Michael R.; Yeates, Todd O.
2014-01-01
possible to extract meaningful information in cases where limited resolution might otherwise prevent initial phasing
Simulation of phase structures
International Nuclear Information System (INIS)
Lawson, J.
1995-01-01
This memo outlines a procedure developed by the author to extract information from phase measurements and produce a simulated phase structure for use in modeling optical systems, including characteristic optics for the Beamlet and NIF laser systems. The report includes an IDL program listing
Report #09-P-0226, August 31, 2009. End users of the Permit Compliance System and Integrated Compliance Information System National Pollutant Discharge Elimination System can override the Significant Non-Compliance data field without more access controls.
Crabill, Norman L.; Dash, Ernie R.
1991-01-01
The weather information requirements for pilots and the deficiencies of the current aviation weather support system in meeting these requirements are defined. As the amount of data available to pilots increases significantly in the near future, expert system technology will be needed to assist pilots in assimilating that information. Some other desirable characteristics of an automation-assisted system for weather data acquisition, dissemination, and assimilation are also described.
Non-completion and informed consent.
Wertheimer, Alan
2014-02-01
There is a good deal of biomedical research that does not produce scientifically useful data because it fails to recruit a sufficient number of subjects. This fact is typically not disclosed to prospective subjects. In general, the guidance about consent concerns the information required to make intelligent self-interested decisions and ignores some of the information required for intelligent altruistic decisions. Bioethics has worried about the 'therapeutic misconception', but has ignored the 'completion misconception'. This article argues that, other things being equal, prospective subjects should be informed about the possibility of non-completion as part of the standard consent process if (1) it is or should be anticipatable that there is a non-trivial possibility of non-completion and (2) that information is likely to be relevant to a prospective subject's decision to consent. The article then considers several objections to the argument, including the objection that disclosing non-completion information would make recruitment even more difficult.
Energy Technology Data Exchange (ETDEWEB)
NONE
1997-03-01
The survey on the reduction measures against greenhouse effect gases was carried out which was proposed by the IEA-GHG phase 3 program. In Japan, various low emission vehicles (LEV) such as electric, methanol and natural gas vehicles are under rapid development. Like France, cost reduction and preparation of fuel filling stations are urgently necessary for the diffusion of LEVs. In New Zealand, air pollution by automobiles is not essential. The Switzerland government is promoting the diffusion of compact electric vehicles, and inhibits the use of conventional automobiles in some tourist resorts. The California state is leading the world by prescribing the bold regulation for preventing the air from pollution. In particular, the state government put automobile manufacturers under an obligation to produce zero emission vehicles (ZEV, electric vehicle) by 2% of passenger cars and trucks from 1998 and to increase ZEVs up to 10% until 2010. This report also includes two papers concerned, `Forestry management for sustainable development` and `Tropical forestry action plan after five years.` 142 refs., 19 figs., 23 tabs.
Mccullough, R. A.; Pinelli, T. E.; Pilley, D. D.; Stohrer, F. F.
1982-01-01
Current practice and usage using selected technical reports; literature relative to the sequential, language, and presentation components of technical reports; and NASA technical report publications standards are discussed. The effctiveness of the technical report as a product for information dissemination is considered.
International Nuclear Information System (INIS)
Read, R.J.; Schierbeek, A.J.
1988-01-01
A phased translation function, which takes advantage of prior phase information to determine the position of an oriented mulecular replacement model, is examined. The function is the coefficient of correlation between the electron density computed with the prior phases and the electron density of the translated model, evaluated in reciprocal space as a Fourier transform. The correlation coefficient used in this work is closely related to an overlap function devised by Colman, Fehlhammer and Bartels. Tests with two protein structures, one of which was solved with the help of the phased translation function, show that little phase information is required to resolve the translation problem, and that the function is relatively insensitive to misorientation of the model. (orig.)
Minder, Franziska; Zuberer, Agnieszka; Brandeis, Daniel; Drechsler, Renate
2018-02-02
There is controversy regarding the clinical efficacy of neurofeedback (NF) and computerized cognitive training (CogT) as treatments for ADHD. Meta-analyses claim that probably blinded teachers observe smaller effects than parents, because they are less biased. We investigated informant-specific effects by manipulating the involvement of informants, by controlling for waiting time effects, and by adding a blinded outcome measure. Seventy-seven children with ADHD were randomly allocated to slow cortical potential NF or to individualized CogT (of attention, working memory or inhibition). The training was conducted in schools (NF: n = 19, CogT: n = 19) or in outpatient clinics (NF: n = 19, CogT: n = 20). Three assessments were scheduled: baseline, followed by a waiting period, pre-training, and post-training. Multivariate Analyses of Variance were conducted to assess parent- and teacher-rated changes in ADHD symptoms and executive functions (EF), and changes according to standardized classroom observations. Both treatments resulted in significant improvements according to informants, with larger effects for parents (ADHD symptoms: parent η p 2 = .32; teacher η p 2 = .10), and according to observations (η p 2 = .19). The setting had no effect on outcome. Considerable waiting time effects were revealed for ADHD symptom ratings by both informants, for EF ratings only by teachers. Changed classroom behavior was uncorrelated with teacher-rated changes. Overall, the results do not support the notion that teachers are more objective while being as sensitive to change as parents. The three sources seem to contribute differential and mostly unrelated pieces of information to the evaluation of treatments.
Pozza, Giandomenico; Borgo, Stefano; Oltramari, Alessandro; Contalbrigo, Laura; Marangon, Stefano
2016-09-08
Ontologies are widely used both in the life sciences and in the management of public and private companies. Typically, the different offices in an organization develop their own models and related ontologies to capture specific tasks and goals. Although there might be an overall coordination, the use of distinct ontologies can jeopardize the integration of data across the organization since data sharing and reusability are sensitive to modeling choices. The paper provides a study of the entities that are typically found at the reception, analysis and report phases in public institutes in the life science domain. Ontological considerations and techniques are introduced and their implementation exemplified by studying the Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe), a public veterinarian institute with different geographical locations and several laboratories. Different modeling issues are discussed like the identification and characterization of the main entities in these phases; the classification of the (types of) data; the clarification of the contexts and the roles of the involved entities. The study is based on a foundational ontology and shows how it can be extended to a comprehensive and coherent framework comprising the different institute's roles, processes and data. In particular, it shows how to use notions lying at the borderline between ontology and applications, like that of knowledge object. The paper aims to help the modeler to understand the core viewpoint of the organization and to improve data transparency. The study shows that the entities at play can be analyzed within a single ontological perspective allowing us to isolate a single ontological framework for the whole organization. This facilitates the development of coherent representations of the entities and related data, and fosters the use of integrated software for data management and reasoning across the company.
Directory of Open Access Journals (Sweden)
Nathalie Pettorelli
2013-01-01
Full Text Available Mangroves are an important bulkhead against climate change: they afford protection for coastal areas from tidal waves and cyclones, and are among the most carbon-rich forests in the tropics. As such, protection of mangroves is an urgent priority. This work provides some new information on patterns of degradation in the Sundarbans, the largest contiguous mangrove forest in the world, which are home to more than 35 reptile species, 120 commercial fish species, 300 bird species and 32 mammal species. Using radar imagery, we contrast and quantify the recent impacts of cyclone Sidr and anthropogenic degradation on this ecosystem. Our results, inferred from changes in radar backscatter, confirm already reported trends in coastline retreat for this region, with areas losing as much as 200 m of coast per year. They also suggest rapid changes in mangrove dynamics for Bangladesh and India, highlighting an overall decrease in mangrove health in the east side of the Sundarbans, and an overall increase in this parameter for the west side of the Sundarbans. As global environmental change takes its toll in this part of the world, more detailed, regular information on mangroves’ distribution and health is required: our study illustrates how different threats experienced by mangroves can be detected and mapped using radar-based information, to guide management action.
Noelle, A.; Hartmann, G. K.; Martin-Torres, F. J.
2010-05-01
The science-softCon "UV/Vis+ Spectra Data Base" is a non-profit project established in August 2000 and is operated in accordance to the "Open Access" definitions and regulations of the CSPR Assessment Panel on Scientific Data and Information (International Council for Science, 2004, HYPERLINK "http://www.science-softcon.de/spectra/cspr.pdf" ICSU Report of the CSPR Assessment Panel on Data and Information; ISBN 0-930357-60-4). The on-line database contains currently about 5600 spectra (from low to very high resolution, at different temperatures and pressures) and datasheets (metadata) of about 850 substances. Additional spectra/datasheets will be added continuously. In addition more than 250 links to on-line free available original publications are provided. The interdisciplinary of this photochemistry database provides a good interaction between different research areas. So, this database is an excellent tool for scientists who investigate on different fields such as atmospheric chemistry, astrophysics, agriculture, analytical chemistry, environmental chemistry, medicine, remote sensing, etc. To ensure the high quality standard of the fast growing UV/Vis+ Spectra Data Base an international "Scientific Advisory Group" (SAG) has been established in 2004. Because of the importance of maintenance of the database the support of the scientific community is crucial. Therefore we would like to encourage all scientists to support this data compilation project thru the provision of new or missing spectral data and information.
Tensor Network Wavefunctions for Topological Phases
Ware, Brayden Alexander
intrinsically fermionic topological phases, i.e. topological phases contructed out of fermions with a nontrivial response to fermion parity defects. A zero correlation length wavefunction and a commuting projector Hamiltonian that realizes this wavefunction as its ground state are constructed. Using an appropriate generalization of the minimally entangled states method for extraction of topological order from the ground states on a torus to the intrinsically fermionic case, we fully characterize the corresponding topological order as Ising x (px - ipy). We argue that this phase can be captured using fermionic tensor networks, expanding the applicability of tensor network methods.
Andersson, Anna; Vimarlund, Vivian; Timpka, Toomas
2002-01-01
There are numerous challenges to overcome before information and communication technology (ICT) can achieve its full potential in process-oriented health-care organizations. One of these challenges is designing systems that meet users' needs, while reflecting a continuously changing organizational environment. Another challenge is to develop ICT that supports both the internal and the external stakeholders' demands. In this study a qualitative research strategy was used to explore the demands on ICT expressed by managers from functional and process units at a community hospitaL The results reveal a multitude of partially competing goals that can make the ICT development process confusing, poor in quality, inefficient and unnecessarily costly. Therefore, from the perspective of ICT development, the main task appears to be to coordinate the different visions and in particular clarify them, as well as to establish the impact that these visions would have on the forthcoming ICT application.
DEFF Research Database (Denmark)
Thygesen, Marianne Kirstine; Holt, Kamila Adellund; Mogensen, Ole
2016-01-01
provided data for statistical analysis. Patients’ difference in change in Sense of Coherence over time was statistically significant in favor of those who had used the website (mean difference 4.42, pwebsite prevented a decrease in self-management of Danish...... of a healthcare-professional developed website, available to both patients and relatives, on patients’ experienced self-management before surgery for ovarian cancer. In an experimental study, Danish women with ovarian cancer were consecutively included if they would participate and had a relative, willing...... to offer attention to the cancer situation. The control group had standard care, the intervention group plus their relatives had additional access to a website with cancer-specific physical, psychical, and practical information. The validated questionnaires Cancer Behavior Inventory and Sense of Coherence...
Phase diagram of the disordered Bose-Hubbard model
International Nuclear Information System (INIS)
Gurarie, V.; Pollet, L.; Prokof'ev, N. V.; Svistunov, B. V.; Troyer, M.
2009-01-01
We establish the phase diagram of the disordered three-dimensional Bose-Hubbard model at unity filling which has been controversial for many years. The theorem of inclusions, proven by Pollet et al. [Phys. Rev. Lett. 103, 140402 (2009)] states that the Bose-glass phase always intervenes between the Mott insulating and superfluid phases. Here, we note that assumptions on which the theorem is based exclude phase transitions between gapped (Mott insulator) and gapless phases (Bose glass). The apparent paradox is resolved through a unique mechanism: such transitions have to be of the Griffiths type when the vanishing of the gap at the critical point is due to a zero concentration of rare regions where extreme fluctuations of disorder mimic a regular gapless system. An exactly solvable random transverse field Ising model in one dimension is used to illustrate the point. A highly nontrivial overall shape of the phase diagram is revealed with the worm algorithm. The phase diagram features a long superfluid finger at strong disorder and on-site interaction. Moreover, bosonic superfluidity is extremely robust against disorder in a broad range of interaction parameters; it persists in random potentials nearly 50 (!) times larger than the particle half-bandwidth. Finally, we comment on the feasibility of obtaining this phase diagram in cold-atom experiments, which work with trapped systems at finite temperature.
International Nuclear Information System (INIS)
Menk, Ralf Hendrik
2008-01-01
All standard (medical) x-ray imaging technologies, rely primarily on the amplitude properties of the incident radiation, and do not depend on its phase. This is unchanged since the discovery by Roentgen that the intensity of an x-ray beam, as measured by the exposure on a film, was related to the relative transmission properties of an object. However, recently various imaging techniques have emerged which depend on the phase of the x-rays as well as the amplitude. Phase becomes important when the beam is coherent and the imaging system is sensitive to interference phenomena. Significant new advances have been made in coherent optic theory and techniques, which now promise phase information in medical imaging. The development of perfect crystal optics and the increasing availability of synchrotron radiation facilities have contributed to a significant increase in the application of phase based imaging in materials and life sciences. Unique source characteristics such as high intensity, monochromaticity, coherence and high collimating provide an ideal source for advanced imaging. Phase contrast imaging has been applied in both projection and computed tomography modes, and recent applications have been made in the field of medical imaging. Due to the underlying principle of X-ray detection conventional image receptors register only intensities of wave fields and not their phases. During the last decade basically five different methods were developed that translate the phase information into intensity variations. These methods are based on measuring the phase shift φ directly (using interference phenomena), the gradient ∇ φ , or the Laplacian ∇ 2 φ. All three methods can be applied to polychromatic X-ray sources keeping in mind that the native source is synchrotron radiation, featuring monochromatic and reasonable coherent X-ray beams. Due to the vast difference in the coefficients that are driven absorption and phase effects (factor 1,000-10,000 in the energy
Smooth Phase Interpolated Keying
Borah, Deva K.
2007-01-01
Smooth phase interpolated keying (SPIK) is an improved method of computing smooth phase-modulation waveforms for radio communication systems that convey digital information. SPIK is applicable to a variety of phase-shift-keying (PSK) modulation schemes, including quaternary PSK (QPSK), octonary PSK (8PSK), and 16PSK. In comparison with a related prior method, SPIK offers advantages of better performance and less complexity of implementation. In a PSK scheme, the underlying information waveform that one seeks to convey consists of discrete rectangular steps, but the spectral width of such a waveform is excessive for practical radio communication. Therefore, the problem is to smooth the step phase waveform in such a manner as to maintain power and bandwidth efficiency without incurring an unacceptably large error rate and without introducing undesired variations in the amplitude of the affected radio signal. Although the ideal constellation of PSK phasor points does not cause amplitude variations, filtering of the modulation waveform (in which, typically, a rectangular pulse is converted to a square-root raised cosine pulse) causes amplitude fluctuations. If a power-efficient nonlinear amplifier is used in the radio communication system, the fluctuating-amplitude signal can undergo significant spectral regrowth, thus compromising the bandwidth efficiency of the system. In the related prior method, one seeks to solve the problem in a procedure that comprises two major steps: phase-value generation and phase interpolation. SPIK follows the two-step approach of the related prior method, but the details of the steps are different. In the phase-value-generation step, the phase values of symbols in the PSK constellation are determined by a phase function that is said to be maximally smooth and that is chosen to minimize the spectral spread of the modulated signal. In this step, the constellation is divided into two groups by assigning, to information symbols, phase values
Stability conditions and phase diagrams for two-component Fermi gases with population imbalance
International Nuclear Information System (INIS)
Chen Qijin; He Yan; Chien, C.-C.; Levin, K.
2006-01-01
Superfluidity in atomic Fermi gases with population imbalance has recently become an exciting research focus. There is considerable disagreement in the literature about the appropriate stability conditions for states in the phase diagram throughout the BCS to Bose-Einstein condensation crossover. Here we discuss these stability conditions for homogeneous polarized superfluid phases, and compare with recent alternative proposals. The requirement of a positive second-order partial derivative of the thermodynamic potential with respect to the fermionic excitation gap Δ (at fixed chemical potentials) is demonstrated to be equivalent to the positive definiteness of the particle number susceptibility matrix. In addition, we show the positivity of the effective pair mass constitutes another nontrivial stability condition. These conditions determine the (local) stability of the system towards phase separation (or other ordered phases). We also study systematically the effects of finite temperature and the related pseudogap on the phase diagrams defined by our stability conditions
Phase Transitions of the Polariton Condensate in 2D Dirac Materials.
Lee, Ki Hoon; Lee, Changhee; Min, Hongki; Chung, Suk Bum
2018-04-13
For the quantum well in an optical microcavity, the interplay of the Coulomb interaction and the electron-photon (e-ph) coupling can lead to the hybridizations of the exciton and the cavity photon known as polaritons, which can form the Bose-Einstein condensate above a threshold density. Additional physics due to the nontrivial Berry phase comes into play when the quantum well consists of the gapped two-dimensional Dirac material such as the transition metal dichalcogenide MoS_{2} or WSe_{2}. Specifically, in forming the polariton, the e-ph coupling from the optical selection rule due to the Berry phase can compete against the Coulomb electron-electron (e-e) interaction. We find that this competition gives rise to a rich phase diagram for the polariton condensate involving both topological and symmetry breaking phase transitions, with the former giving rise to the quantum anomalous Hall and the quantum spin Hall phases.
Phase Transitions of the Polariton Condensate in 2D Dirac Materials
Lee, Ki Hoon; Lee, Changhee; Min, Hongki; Chung, Suk Bum
2018-04-01
For the quantum well in an optical microcavity, the interplay of the Coulomb interaction and the electron-photon (e -ph) coupling can lead to the hybridizations of the exciton and the cavity photon known as polaritons, which can form the Bose-Einstein condensate above a threshold density. Additional physics due to the nontrivial Berry phase comes into play when the quantum well consists of the gapped two-dimensional Dirac material such as the transition metal dichalcogenide MoS2 or WSe2 . Specifically, in forming the polariton, the e -ph coupling from the optical selection rule due to the Berry phase can compete against the Coulomb electron-electron (e -e ) interaction. We find that this competition gives rise to a rich phase diagram for the polariton condensate involving both topological and symmetry breaking phase transitions, with the former giving rise to the quantum anomalous Hall and the quantum spin Hall phases.
International Nuclear Information System (INIS)
Pietrucci, Fabio; Martoňák, Roman
2015-01-01
Systematically resolving different crystalline phases starting from the atomic positions, a mandatory step in algorithms for the prediction of structures or for the simulation of phase transitions, can be a non-trivial task. Extending to amorphous phases and liquids which lack the discrete symmetries, the problem becomes even more difficult, involving subtle topological differences at medium range that, however, are crucial to the physico-chemical and spectroscopic properties of the corresponding materials. Typically, system-tailored order parameters are devised, like global or local symmetry indicators, ring populations, etc. We show that a recently introduced metric provides a simple and general solution to this intricate problem. In particular, we demonstrate that a map can be traced displaying distances among water phases, including crystalline as well as amorphous states and the liquid, consistently with experimental knowledge in terms of phase diagram, structural features, and preparation routes
Hydrodynamics of phase transition fronts and the speed of sound in the plasma
International Nuclear Information System (INIS)
Leitao, Leonardo; Mégevand, Ariel
2015-01-01
The growth of bubbles in cosmological first-order phase transitions involves nontrivial hydrodynamics. For that reason, the study of the propagation of phase transition fronts often requires several approximations. A frequently used approximation consists in describing the two phases as being composed only of radiation and vacuum energy (the so-called bag equation of state). We show that, in realistic models, the speed of sound in the low-temperature phase is generally smaller than that of radiation, and we study the hydrodynamics in such a situation. We find in particular that a new kind of hydrodynamical solution may be possible, which does not arise in the bag model. We obtain analytic results for the efficiency of the transfer of latent heat to bulk motions of the plasma, as a function of the speed of sound in each phase
Hydrodynamics of phase transition fronts and the speed of sound in the plasma
Energy Technology Data Exchange (ETDEWEB)
Leitao, Leonardo, E-mail: lleitao@mdp.edu.ar; Mégevand, Ariel, E-mail: megevand@mdp.edu.ar
2015-02-15
The growth of bubbles in cosmological first-order phase transitions involves nontrivial hydrodynamics. For that reason, the study of the propagation of phase transition fronts often requires several approximations. A frequently used approximation consists in describing the two phases as being composed only of radiation and vacuum energy (the so-called bag equation of state). We show that, in realistic models, the speed of sound in the low-temperature phase is generally smaller than that of radiation, and we study the hydrodynamics in such a situation. We find in particular that a new kind of hydrodynamical solution may be possible, which does not arise in the bag model. We obtain analytic results for the efficiency of the transfer of latent heat to bulk motions of the plasma, as a function of the speed of sound in each phase.
Effects of phase transition induced density fluctuations on pulsar dynamics
Directory of Open Access Journals (Sweden)
Partha Bagchi
2015-07-01
Full Text Available We show that density fluctuations during phase transitions in pulsar cores may have non-trivial effects on pulsar timings, and may also possibly account for glitches and anti-glitches. These density fluctuations invariably lead to non-zero off-diagonal components of the moment of inertia, leading to transient wobbling of star. Thus, accurate measurements of pulsar timing and intensity modulations (from wobbling may be used to identify the specific pattern of density fluctuations, hence the particular phase transition, occurring inside the pulsar core. Changes in quadrupole moment from rapidly evolving density fluctuations during the transition, with very short time scales, may provide a new source for gravitational waves.
Dynamic phase transition in diffusion-limited reactions
International Nuclear Information System (INIS)
Tauber, U.C.
2002-01-01
Many non-equilibrium systems display dynamic phase transitions from active to absorbing states, where fluctuations cease entirely. Based on a field theory representation of the master equation, the critical behavior can be analyzed by means of the renormalization group. The resulting universality classes for single-species systems are reviewed here. Generically, the critical exponents are those of directed percolation (Reggeon field theory), with critical dimension d c = 4. Yet local particle number parity conservation in even-offspring branching and annihilating random walks implies an inactive phase (emerging below d c = 4/3) that is characterized by the power laws of the pair annihilation reaction, and leads to different critical exponents at the transition. For local processes without memory, the pair contact process with diffusion represents the only other non-trivial universality class. The consistent treatment of restricted site occupations and quenched random reaction rates are important open issues (Author)
Phase Referencing in Optical Interferometry
Filho, Mercedes E.; Garcia, Paulo; Duvert, Gilles; Duchene, Gaspard; Thiebaut, Eric; Young, John; Absil, Olivier; Berger, Jean-Phillipe; Beckert, Thomas; Hoenig, Sebastian; Schertl, Dieter; Weigelt, Gerd; Testi, Leonardo; Tatuli, Eric; Borkowski, Virginie
2008-01-01
One of the aims of next generation optical interferometric instrumentation is to be able to make use of information contained in the visibility phase to construct high dynamic range images. Radio and optical interferometry are at the two extremes of phase corruption by the atmosphere. While in radio it is possible to obtain calibrated phases for the science objects, in the optical this is currently not possible. Instead, optical interferometry has relied on closure phase techniques to produce...
Ahmad, Zahoor; Hanif, Muhammad
2013-01-01
The development of estimators of population parameters based on two-phase sampling schemes has seen a dramatic increase in the past decade. Various authors have developed estimators of population using either one or two auxiliary variables. The present volume is a comprehensive collection of estimators available in single and two phase sampling. The book covers estimators which utilize information on single, two and multiple auxiliary variables of both quantitative and qualitative nature. Th...
DEFF Research Database (Denmark)
Bjerrum, Peter; Olsen, Kasper Nefer
2001-01-01
Inform@ed space Sensorial Perception And Computer Enchancement - bidrag til Nordisk Arkitekturforskningsforenings IT-konference, AAA april 2001.......Inform@ed space Sensorial Perception And Computer Enchancement - bidrag til Nordisk Arkitekturforskningsforenings IT-konference, AAA april 2001....
For information - Geneva University
A. Cervera Villanueva
2004-01-01
Ecole de physique Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 TéL: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 3 November 2004 PARTICLE PHYSICS SEMINAR at 17.00 hrs Stückelberg Auditorium Tools for Electroweak physics at LHC by Pr. Stanislaw JADACH, Department of Particle Theory, Institute of Nuclear Physics, Cracow, Poland Experiments at the Large Hadron Collider (LHC) will provide a large amount of high quality data on the production of the W and Z bosons. It will be a highly nontrivial task to exploit fully these data in order to measure precisely the mass of the W boson and its anomalous couplings. Other challenges are to measure with high precision parton luminosities and to find the presence of new physics at multi-TeV scales. For this purpose one needs a new generation of Monte Carlo tools that must include QCD, QED and Electroweak calculations beyond-the-leading-order. Information : http://dp...
Noise enhances information transfer in hierarchical networks.
Czaplicka, Agnieszka; Holyst, Janusz A; Sloot, Peter M A
2013-01-01
We study the influence of noise on information transmission in the form of packages shipped between nodes of hierarchical networks. Numerical simulations are performed for artificial tree networks, scale-free Ravasz-Barabási networks as well for a real network formed by email addresses of former Enron employees. Two types of noise are considered. One is related to packet dynamics and is responsible for a random part of packets paths. The second one originates from random changes in initial network topology. We find that the information transfer can be enhanced by the noise. The system possesses optimal performance when both kinds of noise are tuned to specific values, this corresponds to the Stochastic Resonance phenomenon. There is a non-trivial synergy present for both noisy components. We found also that hierarchical networks built of nodes of various degrees are more efficient in information transfer than trees with a fixed branching factor.
Yang, Fan; Liu, Ren-Bao
2013-03-01
Quantum evolution of particles under strong fields can be approximated by the quantum trajectories that satisfy the stationary phase condition in the Dirac-Feynmann path integrals. The quantum trajectories are the key concept to understand strong-field optics phenomena, such as high-order harmonic generation (HHG), above-threshold ionization (ATI), and high-order terahertz siedeband generation (HSG). The HSG in semiconductors may have a wealth of physics due to the possible nontrivial ``vacuum'' states of band materials. We find that in a spin-orbit-coupled semiconductor, the cyclic quantum trajectories of an electron-hole pair under a strong terahertz field accumulates nontrivial Berry phases. We study the monolayer MoS2 as a model system and find that the Berry phases are given by the Faraday rotation angles of the pulse emission from the material under short-pulse excitation. This result demonstrates an interesting Berry phase dependent effect in the extremely nonlinear optics of semiconductors. This work is supported by Hong Kong RGC/GRF 401512 and the CUHK Focused Investments Scheme.
Spiegel, Jerry M; Lockhart, Karen; Dyck, Carmen; Wilson, Andrea; O'Hara, Lyndsay; Yassi, Annalee
2012-08-06
Although information systems (IS) have been extensively applied in the health sector worldwide, few initiatives have addressed the health and safety of health workers, a group acknowledged to be at high risk of injury and illness, as well as in great shortage globally, particularly in low and middle-income countries. Adapting a context-mechanism-outcome case study design, we analyze our team's own experience over two decades to address this gap: in two different Canadian provinces; and two distinct South African settings. Applying a realist analysis within an adapted structuration theory framing sensitive to power relations, we explore contextual (socio-political and technological) characteristics and mechanisms affecting outcomes at micro, meso and macro levels. Technological limitations hindered IS usefulness in the initial Canadian locale, while staffing inadequacies amid pronounced power imbalances affecting governance restricted IS usefulness in the subsequent Canadian application. Implementation in South Africa highlighted the special care needed to address power dynamics regarding both worker-employer relations (relevant to all occupational health settings) and North-south imbalances (common to all international interactions). Researchers, managers and front-line workers all view IS implementation differently; relationships amongst the workplace parties and between community and academic partners have been pivotal in determining outcome in all circumstances. Capacity building and applying creative commons and open source solutions are showing promise, as is international collaboration. There is worldwide consensus on the need for IS use to protect the health workforce. However, IS implementation is a resource-intensive undertaking; regardless of how carefully designed the software, contextual factors and the mechanisms adopted to address these are critical to mitigate threats and achieve outcomes of interest to all parties. Issues specific to IS development
Directory of Open Access Journals (Sweden)
Spiegel Jerry M
2012-08-01
Full Text Available Abstract Background Although information systems (IS have been extensively applied in the health sector worldwide, few initiatives have addressed the health and safety of health workers, a group acknowledged to be at high risk of injury and illness, as well as in great shortage globally, particularly in low and middle-income countries. Methods Adapting a context-mechanism-outcome case study design, we analyze our team’s own experience over two decades to address this gap: in two different Canadian provinces; and two distinct South African settings. Applying a realist analysis within an adapted structuration theory framing sensitive to power relations, we explore contextual (socio-political and technological characteristics and mechanisms affecting outcomes at micro, meso and macro levels. Results Technological limitations hindered IS usefulness in the initial Canadian locale, while staffing inadequacies amid pronounced power imbalances affecting governance restricted IS usefulness in the subsequent Canadian application. Implementation in South Africa highlighted the special care needed to address power dynamics regarding both worker-employer relations (relevant to all occupational health settings and North–south imbalances (common to all international interactions. Researchers, managers and front-line workers all view IS implementation differently; relationships amongst the workplace parties and between community and academic partners have been pivotal in determining outcome in all circumstances. Capacity building and applying creative commons and open source solutions are showing promise, as is international collaboration. Conclusions There is worldwide consensus on the need for IS use to protect the health workforce. However, IS implementation is a resource-intensive undertaking; regardless of how carefully designed the software, contextual factors and the mechanisms adopted to address these are critical to mitigate threats and achieve
Energy Technology Data Exchange (ETDEWEB)
NONE
1995-08-01
The Utility PhotoVoltaic Group (UPVG), supported by member dues and a grant from the US Department of Energy, has as its mission the acceleration of the use of cost-effective small-scale and emerging large-scale applications of photovoltaics for the benefit of electric utilities and their customers. Formed in October, 1992, with the support of the American Public Power Association, Edison Electric Institute, and the National Rural Electric Cooperative Association, the UPVG currently has 90 members from all sectors of the electric utility industry. The UPVG`s efforts as conceived were divided into four phases: Phase 0--program plan; Phase 1--organization and strategy development; Phase 2--creating market assurance; and Phase 3--higher volume purchases. The Phase 0 effort developed the program plan and was completed early in 1993. The Phase 1 goal was to develop the necessary background information and analysis to lead to a decision as to which strategies could be undertaken by utilities to promote greater understanding of PV markets and achieve increased volumes of PV purchases. This report provides the details of the UPVG`s Phase 2 efforts to initiate TEAM-UP, its multiyear, 50-MW hardware initiative.
International Nuclear Information System (INIS)
1995-08-01
The Utility PhotoVoltaic Group (UPVG), supported by member dues and a grant from the US Department of Energy, has as its mission the acceleration of the use of cost-effective small-scale and emerging large-scale applications of photovoltaics for the benefit of electric utilities and their customers. Formed in October, 1992, with the support of the American Public Power Association, Edison Electric Institute, and the National Rural Electric Cooperative Association, the UPVG currently has 90 members from all sectors of the electric utility industry. The UPVG's efforts as conceived were divided into four phases: Phase 0--program plan; Phase 1--organization and strategy development; Phase 2--creating market assurance; and Phase 3--higher volume purchases. The Phase 0 effort developed the program plan and was completed early in 1993. The Phase 1 goal was to develop the necessary background information and analysis to lead to a decision as to which strategies could be undertaken by utilities to promote greater understanding of PV markets and achieve increased volumes of PV purchases. This report provides the details of the UPVG's Phase 2 efforts to initiate TEAM-UP, its multiyear, 50-MW hardware initiative
International Nuclear Information System (INIS)
Frohlich, J.
1976-01-01
We prove that a Symanzik--Nelson positive quantum field theory, i.e., a quantum field theory derived from a Euclidean field theory, has a unique decomposition into pure phases which preserves Symanzik--Nelson positivity and Poincare covariance. We derive useful sufficient conditions for the breakdown of an internal symmetry of such a theory in its pure phases, for the self-adjointness and nontrivially (in the sense of Borchers classes) of its quantum fields, and the existence of time-ordered and retarded products. All these general results are then applied to the P (phi) 2 and the phi 3 4 quantum field models
Sole, Ricard V; Solé, Ricard V; SolÃ©, Ricard V; Sol, Ricard V; Solé, Ricard V
2011-01-01
Phase transitions--changes between different states of organization in a complex system--have long helped to explain physics concepts, such as why water freezes into a solid or boils to become a gas. How might phase transitions shed light on important problems in biological and ecological complex systems? Exploring the origins and implications of sudden changes in nature and society, Phase Transitions examines different dynamical behaviors in a broad range of complex systems. Using a compelling set of examples, from gene networks and ant colonies to human language and the degradation of diverse ecosystems, the book illustrates the power of simple models to reveal how phase transitions occur. Introductory chapters provide the critical concepts and the simplest mathematical techniques required to study phase transitions. In a series of example-driven chapters, Ricard Solé shows how such concepts and techniques can be applied to the analysis and prediction of complex system behavior, including the origins of ...
Phase alteration compensation in reflection digital holography
International Nuclear Information System (INIS)
Rincon, O; Amezquita, R; Monroy, F
2011-01-01
The phase maps obtained from digital holographic microscopy techniques carry information about the axial lengths of the object under study. Additionally, these phase maps have information of tilt and curvatures with origin in the off-axis geometry and the magnification lenses system, respectively. Only a complete compensation of these extra phases allows a correct interpretation of the phase information. In this article a numerical strategy to compensate for these alterations is designed, using a phase mask located in different planes. This strategy is applied in the measurement of a phase steps plate using a digital holography setup.
Fermi points and topological quantum phase transitions in a multi-band superconductor.
Puel, T O; Sacramento, P D; Continentino, M A
2015-10-28
The importance of models with an exact solution for the study of materials with non-trivial topological properties has been extensively demonstrated. The Kitaev model plays a guiding role in the search for Majorana modes in condensed matter systems. Also, the sp-chain with an anti-symmetric mixing among the s and p bands is a paradigmatic example of a topological insulator with well understood properties. Interestingly, these models share the same universality class for their topological quantum phase transitions. In this work we study a two-band model of spinless fermions with attractive inter-band interactions. We obtain its zero temperature phase diagram, which presents a rich variety of phases including a Weyl superconductor and a topological insulator. The transition from the topological to the trivial superconducting phase has critical exponents different from those of Kitaev's model.
Nonequilibrium phase transitions in a model with social influence of inflexible units
International Nuclear Information System (INIS)
Jiang, Luo-luo; Hua, Da-yin; Chen, Ting
2007-01-01
In many social, economical and biological systems, the evolution of the states of interacting units cannot be simply treated with a physical law in the realm of traditional statistical mechanics. We propose a simple binary-state model to discuss the effect of the inflexible units on the dynamical behavior of a social system, in which a unit may have a chance to keep its state with a probability 1 - q even though its state is different from those of the majority of its interacting neighbors. It is found that the effect of these inflexible units can lead to a nontrivial phase diagram
Nonequilibrium phase transitions in a model with social influence of inflexible units
Energy Technology Data Exchange (ETDEWEB)
Jiang, Luo-luo; Hua, Da-yin; Chen, Ting [Physics Department, Ningbo University, Ningbo 315211 (China)
2007-09-14
In many social, economical and biological systems, the evolution of the states of interacting units cannot be simply treated with a physical law in the realm of traditional statistical mechanics. We propose a simple binary-state model to discuss the effect of the inflexible units on the dynamical behavior of a social system, in which a unit may have a chance to keep its state with a probability 1 - q even though its state is different from those of the majority of its interacting neighbors. It is found that the effect of these inflexible units can lead to a nontrivial phase diagram.
Phase structure rewrite systems in information retrieval
Klingbiel, P. H.
1985-01-01
Operational level automatic indexing requires an efficient means of normalizing natural language phrases. Subject switching requires an efficient means of translating one set of authorized terms to another. A phrase structure rewrite system called a Lexical Dictionary is explained that performs these functions. Background, operational use, other applications and ongoing research are explained.
Mobile Water Quality Information Tool, Phase I
National Aeronautics and Space Administration — Water quality remote sensing has grown to allow for operational monitoring of trophic status, assessment of cyanobacteria blooms, and historical and trend analysis...
Properties of hadronic matter near the phase transition
Energy Technology Data Exchange (ETDEWEB)
Noronha-Hostler, Jacquelyn
2010-12-08
According to Hagedorn, hadrons should follow an exponential mass spectrum, which the known hadrons follow only up to masses of M{approx}2 GeV. Beyond this point the mass spectrum is flat, which indicates that there are ''missing'' hadrons, that could potentially contribute significantly to experimental observables. In this thesis I investigate the influence of these ''missing'' Hagedorn states on various experimental signatures of QGP. Strangeness enhancement is considered a signal for QGP because hadronic interactions (even including multi-mesonic reactions) underpredict the hadronic yields (especially for strange particles) at the Relativistic Heavy Ion Collider, RHIC. We show here that the missing Hagedorn states provide extra degrees of freedom that can contribute to fast chemical equilibration times for a hadron gas. We develop a dynamical scheme in which possible Hagedorn states contribute to fast chemical equilibration times of X anti X pairs (where X=p, K, {lambda}, or {omega}) inside a hadron gas and just below the critical temperature. Within this scheme, we use master equations and derive various analytical estimates for the chemical equilibration times. Applying a Bjorken picture to the expanding fireball, the hadrons can, indeed, quickly chemically equilibrate for both an initial overpopulation or underpopulation of Hagedorn resonances. Our hadron resonance gas model, including the additional Hagedorn states, is used to obtain an upper bound on the shear viscosity to entropy density ratio, {eta}/s, of hadronic matter near T{sub c} that is close to 1/(4/{pi}). We show how the measured particle ratios can be used to provide non-trivial information about T{sub c} of the QCD phase transition. This is obtained by including the effects of highly massive Hagedorn resonances on statistical models, which are generally used to describe hadronic yields. The inclusion of the ''missing'' Hagedorn states
Properties of hadronic matter near the phase transition
International Nuclear Information System (INIS)
Noronha-Hostler, Jacquelyn
2010-01-01
According to Hagedorn, hadrons should follow an exponential mass spectrum, which the known hadrons follow only up to masses of M∼2 GeV. Beyond this point the mass spectrum is flat, which indicates that there are ''missing'' hadrons, that could potentially contribute significantly to experimental observables. In this thesis I investigate the influence of these ''missing'' Hagedorn states on various experimental signatures of QGP. Strangeness enhancement is considered a signal for QGP because hadronic interactions (even including multi-mesonic reactions) underpredict the hadronic yields (especially for strange particles) at the Relativistic Heavy Ion Collider, RHIC. We show here that the missing Hagedorn states provide extra degrees of freedom that can contribute to fast chemical equilibration times for a hadron gas. We develop a dynamical scheme in which possible Hagedorn states contribute to fast chemical equilibration times of X anti X pairs (where X=p, K, Λ, or Ω) inside a hadron gas and just below the critical temperature. Within this scheme, we use master equations and derive various analytical estimates for the chemical equilibration times. Applying a Bjorken picture to the expanding fireball, the hadrons can, indeed, quickly chemically equilibrate for both an initial overpopulation or underpopulation of Hagedorn resonances. Our hadron resonance gas model, including the additional Hagedorn states, is used to obtain an upper bound on the shear viscosity to entropy density ratio, η/s, of hadronic matter near T c that is close to 1/(4/π). We show how the measured particle ratios can be used to provide non-trivial information about T c of the QCD phase transition. This is obtained by including the effects of highly massive Hagedorn resonances on statistical models, which are generally used to describe hadronic yields. The inclusion of the ''missing'' Hagedorn states creates a dependence of the thermal fits on the Hagedorn temperature, T H , and leads to a
International Nuclear Information System (INIS)
Radhakrishnan, B.; Gorti, S.B.; Clarno, K.; Tonks, M.R.
2015-01-01
In this work, the phase-field method and its application to microstructure evolution in reactor fuel and clad are discussed. The examples highlight the capability of the phase-field method to capture evolution processes that are influenced by both thermal and elastic stress fields that are caused by microstructural changes in the solid-state. The challenges that need to be overcome before the technique can become predictive and material-specific are discussed. (authors)
Strange metals and quantum phase transitions from gauge/gravity duality
Liu, Hong
2011-03-01
Metallic materials whose thermodynamic and transport properties differ significantly from those predicted by Fermi liquid theory, so-called non-Fermi liquids, include the strange metal phase of cuprate superconductors, and heavy fermion systems near a quantum phase transition. We use gauge/gravity duality to identify a class of non-Fermi liquids. Their low-energy behavior is governed by a nontrivial infrared fixed point which exhibits non-analytic scaling behavior only in the temporal direction. Some representatives of this class have single-particle spectral functions and transport behavior similar to those of the strange metals, with conductivity inversely proportional to the temperature. Such holographic systems may also exhibit novel ``magnetic instabilities'', where the quantum critical behavior near the transition involves a nontrivial interplay between local and bulk physics, with the local physics again described by a similar infrared fixed point. The resulting quantum phase transitions do not obey the standard Landau-Ginsburg-Wilson paradigm and resemble those of the heavy fermion quantum critical points.
Spatiotemporal Wave Patterns: Information Dynamics
Energy Technology Data Exchange (ETDEWEB)
Mikhail Rabinovich; Lev Tsimring
2006-01-20
Pattern formation has traditionally been studied in non-equilibrium physics from the viewpoint of describing the basic structures and their interactions. While this is still an important area of research, the emphasis in the last few years has shifted towards analysis of specific properties of patterns in various complex media. For example, diverse and unexpected phenomena occur in neuro-like media that are characterized by highly non-trivial local dynamics. We carried out an active research program on analysis of spatio-temporal patterns in various physical systems (convection, oscillating fluid layer, soap film), as well as in neuro-like media, with an emphasis on informational aspects of the dynamics. Nonlinear nonequilibrium media and their discrete analogs have a unique ability to represent, memorize, and process the information contained in spatio-temporal patterns. Recent neurophysiological experiments demonstrated a certain universality of spatio-temporal representation of information by neural ensembles. Information processing is also revealed in the spatio-temporal dynamics of cellular patterns in nonequilibrium media. It is extremely important for many applications to study the informational aspects of these dynamics, including the origins and mechanisms of information generation, propagation and storage. Some of our results are: the discovery of self-organization of periodically oscillatory patterns in chaotic heterogeneous media; the analysis of the propagation of the information along a chaotic media as function of the entropy of the signal; the analysis of wave propagation in discrete non-equilibrium media with autocatalytic properties, which simulates the calcium dynamics in cellular membranes. Based on biological experiments we suggest the mechanism by which the spatial sensory information is transferred into the spatio-temporal code in the neural media. We also found a new mechanism of self-pinning in cellular structures and the related phenomenon
Emergence of topological and topological crystalline phases in TlBiS2 and TlSbS2
Zhang, Qingyun; Cheng, Yingchun; Schwingenschlö gl, Udo
2015-01-01
Using first-principles calculations, we investigate the band structure evolution and topological phase transitions in TlBiS2 and TlSbS2 under hydrostatic pressure as well as uniaxial and biaxial strain. The phase transitions are identified by parity analysis and by calculating the surface states. Zero, one, and four Dirac cones are found for the (111) surfaces of both TlBiS2 and TlSbS2 when the pressure grows, which confirms trivial-nontrivial-trivial phase transitions. The Dirac cones at the (M) over bar points are anisotropic with large out-of-plane component. TlBiS2 shows normal, topological, and topological crystalline insulator phases under hydrostatic pressure, thus being the first compound to exhibit a phase transition from a topological to a topological crystalline insulator.
Emergence of topological and topological crystalline phases in TlBiS2 and TlSbS2
Zhang, Qingyun
2015-02-11
Using first-principles calculations, we investigate the band structure evolution and topological phase transitions in TlBiS2 and TlSbS2 under hydrostatic pressure as well as uniaxial and biaxial strain. The phase transitions are identified by parity analysis and by calculating the surface states. Zero, one, and four Dirac cones are found for the (111) surfaces of both TlBiS2 and TlSbS2 when the pressure grows, which confirms trivial-nontrivial-trivial phase transitions. The Dirac cones at the (M) over bar points are anisotropic with large out-of-plane component. TlBiS2 shows normal, topological, and topological crystalline insulator phases under hydrostatic pressure, thus being the first compound to exhibit a phase transition from a topological to a topological crystalline insulator.
Vermont Center for Geographic Information — The stream geomorphic assessment (SGA) is a physical assessment competed by geomorphologists to determine the condition and sensitivity of a stream. The Phase 2 SGA...
Phase transitions and quantum entropy
International Nuclear Information System (INIS)
Arrachea, L.; Canosa, N.; Plastino, A.; Portesi, M.; Rossignoli, R.
1990-01-01
An examination is made of the possibility to predict phase transitions of the fundamental state of finite quantum system, knowing the quantum entropy of these states, defined on the basis of the information theory. (Author). 7 refs., 3 figs
Vermont Center for Geographic Information — The stream geomorphic assessment (SGA) is a physical assessment competed by geomorphologists to determine the condition and sensitivity of a stream. The Phase 1 SGA...
Anomaly constraints on deconfinement and chiral phase transition
Shimizu, Hiroyuki; Yonekura, Kazuya
2018-05-01
We study the constraints on thermal phase transitions of SU (Nc) gauge theories by using the 't Hooft anomaly involving the center symmetry and chiral symmetry. We consider two cases of massless fermions: (i) adjoint fermions and (ii) Nf flavors of fundamental fermions with a nontrivial greatest common divisor, gcd (Nc,Nf)≠1 . For the first case (i), we show that the chiral symmetry restoration in terms of the standard Landau-Ginzburg effective action is impossible at a temperature lower than that of deconfinement. For the second case (ii), we introduce a modified version of the center symmetry, which we call center-flavor symmetry, and draw similar conclusions under a certain definition of confinement. Moreover, at zero temperature, our results give a partial explanation of the appearance of dual magnetic gauge groups in (supersymmetric) QCD when gcd (Nc,Nf)≠1 .
CP-odd phase correlations and electric dipole moments
International Nuclear Information System (INIS)
Olive, Keith A.; Pospelov, Maxim; Ritz, Adam; Santoso, Yudi
2005-01-01
We revisit the constraints imposed by electric dipole moments (EDMs) of nucleons and heavy atoms on new CP-violating sources within supersymmetric theories. We point out that certain two-loop renormalization group corrections induce significant mixing between the basis-invariant CP-odd phases. In the framework of the constrained minimal supersymmetric standard model, the CP-odd invariant related to the soft trilinear A-phase at the grand unified theory (GUT) scale, θ A , induces nontrivial and distinct CP-odd phases for the three gaugino masses at the weak scale. The latter give one-loop contributions to EDMs enhanced by tanβ, and can provide the dominant contribution to the electron EDM induced by θ A . We perform a detailed analysis of the EDM constraints within the constrained minimal supersymmetric standard model, exhibiting the reach, in terms of sparticle spectra, which may be obtained assuming generic phases, as well as the limits on the CP-odd phases for some specific parameter points where detailed phenomenological studies are available. We also illustrate how this reach will expand with results from the next generation of experiments which are currently in development
Tunable topological phases in photonic and phononic crystals
Chen, Zeguo
2018-02-18
Topological photonics/phononics, inspired by the discovery of topological insulators, is a prosperous field of research, in which remarkable one-way propagation edge states are robust against impurities or defect without backscattering. This dissertation discusses the implementation of multiple topological phases in specific designed photonic and phononic crystals. First, it reports a tunable quantum Hall phase in acoustic ring-waveguide system. A new three-band model focused on the topological transitions at the Γ point is studied, which gives the functionality that nontrivial topology can be tuned by changing the strengths of the couplings and/or the broken time-reversal symmetry. The resulted tunable topological edge states are also numerically verified. Second, based on our previous studied acoustic ring-waveguide system, we introduce anisotropy by tuning the couplings along different directions. We find that the bandgap topology is related to the frequency and directions. We report our proposal on a frequency filter designed from such an anisotropic topological phononic crystal. Third, motivated by the recent progress on quantum spin Hall phases, we propose a design of time-reversal symmetry broken quantum spin Hall insulators in photonics, in which a new quantum anomalous Hall phase emerges. It supports a chiral edge state with certain spin orientations, which is robust against the magnetic impurities. We also report the realization of the quantum anomalous Hall phase in phononics.
CP-odd Phase Correlations and Electric Dipole Moments
Olive, Keith A; Ritz, A; Santoso, Y; Olive, Keith A.; Pospelov, Maxim; Ritz, Adam; Santoso, Yudi
2005-01-01
We revisit the constraints imposed by electric dipole moments (EDMs) of nucleons and heavy atoms on new CP-violating sources within supersymmetric theories. We point out that certain two-loop renormalization group corrections induce significant mixing between the basis-invariant CP-odd phases. In the framework of the constrained minimal supersymmetric standard model (CMSSM), the CP-odd invariant related to the soft trilinear A-phase at the GUT scale, theta_A, induces non-trivial and distinct CP-odd phases for the three gaugino masses at the weak scale. The latter give one-loop contributions to EDMs enhanced by tan beta, and can provide the dominant contribution to the electron EDM induced by theta_A. We perform a detailed analysis of the EDM constraints within the CMSSM, exhibiting the reach, in terms of sparticle spectra, which may be obtained assuming generic phases, as well as the limits on the CP-odd phases for some specific parameter points where detailed phenomenological studies are available. We also i...
Gross, D. H. E.
1997-01-01
This review is addressed to colleagues working in different fields of physics who are interested in the concepts of microcanonical thermodynamics, its relation and contrast to ordinary, canonical or grandcanonical thermodynamics, and to get a first taste of the wide area of new applications of thermodynamical concepts like hot nuclei, hot atomic clusters and gravitating systems. Microcanonical thermodynamics describes how the volume of the N-body phase space depends on the globally conserved quantities like energy, angular momentum, mass, charge, etc. Due to these constraints the microcanonical ensemble can behave quite differently from the conventional, canonical or grandcanonical ensemble in many important physical systems. Microcanonical systems become inhomogeneous at first-order phase transitions, or with rising energy, or with external or internal long-range forces like Coulomb, centrifugal or gravitational forces. Thus, fragmentation of the system into a spatially inhomogeneous distribution of various regions of different densities and/or of different phases is a genuine characteristic of the microcanonical ensemble. In these cases which are realized by the majority of realistic systems in nature, the microcanonical approach is the natural statistical description. We investigate this most fundamental form of thermodynamics in four different nontrivial physical cases: (I) Microcanonical phase transitions of first and second order are studied within the Potts model. The total energy per particle is a nonfluctuating order parameter which controls the phase which the system is in. In contrast to the canonical form the microcanonical ensemble allows to tune the system continuously from one phase to the other through the region of coexisting phases by changing the energy smoothly. The configurations of coexisting phases carry important informations about the nature of the phase transition. This is more remarkable as the canonical ensemble is blind against these
Electron Holography: phases matter.
Lichte, Hannes
2013-06-01
Essentially, all optics is wave optics, be it with light, X-rays, neutrons or electrons. The information transfer from the object to the image can only be understood in terms of waves given by amplitude and phase. However, phases are difficult to measure: for slowly oscillating waves such as sound or low-frequency electromagnetic waves, phases can be measured directly; for high frequencies this has to be done by heterodyne detection, i.e. superposition with a reference and averaging over time. In optics, this is called interferometry. Because interference is mostly very difficult to achieve, phases have often been considered 'hidden variables' seemingly pulling the strings from backstage, only visible by their action on the image intensity. This was almost the case in conventional Electron Microscopy with the phase differences introduced by an object. However, in the face of the urgent questions from solid state physics and materials science, these phases have to be determined precisely, because they encode the most dominant object properties, such as charge distributions and electromagnetic fields. After more than six decades of very patient advancement, electron interferometry and holography offer unprecedented analytical facilities down to an atomic scale. Akira Tonomura has prominently contributed to the present state.
International Nuclear Information System (INIS)
Edwards, Robert; Huang, Zhengyu
2001-01-01
identified that can efficiently address these requirements and is shown in Fig. 1. The host computer and target computer work cooperatively under the MATLAB Real-Time Workshop environment. The principal user interaction takes place on the host computer where parameter adjustments are initiated and some elementary information displays are presented. The hybrid BWR-simulation application code is generated in the host computer with SIMULINK and is downloaded to the xPC target option of the Real-Time Workshop (target computer). The target computer performs boiling channel thermal-hydraulic simulation and control of the experimental changeable reactivity device (ECRD) in the TRIGA reactor. The target computer is connected to the reactor through a DA/AD card. The TRIGA reactor power is measured, and a control signal is sent to the ECRD drive mechanism to simulate the BWR reactivity feedback. Desired hybrid simulation of BWR behavior is controlled by adjusting parameters in the host computer. The graph computer retrieves measured reactor power, which serves as the fundamental mode power of the BWR, and the simulated first harmonic power from the target computer. Spatial power distribution is calculated from these data, and the reactor physics model in the graph computer and 3-D display of BWR power of the two modes together with the total power is displayed there. BWR out-of-phase oscillation is successfully simulated with the new HRS setup. By adjusting the reactivity feedback gains from boiling channels to the TRIGA reactor and to the first harmonic mode power simulation, limit cycle can be generated with both reactor power and the simulated first harmonic power. Shown in Fig. 2 is the 3-D display of spatial power distributions of fundamental mode, first harmonic, and total powers over the reactor cross section at a certain time in an instability event. (authors)
Group Lifting Structures For Multirate Filter Banks, II: Linear Phase Filter Banks
Energy Technology Data Exchange (ETDEWEB)
Brislawn, Christopher M [Los Alamos National Laboratory
2008-01-01
The theory of group lifting structures is applied to linear phase lifting factorizations for the two nontrivial classes of two-channel linear phase perfect reconstruction filter banks, the whole-and half-sample symmetric classes. Group lifting structures defined for the reversible and irreversible classes of whole-and half-sample symmetric filter banks are shown to satisfy the hypotheses of the uniqueness theorem for group lifting structures. It follows that linear phase lifting factorizations of whole-and half-sample symmetric filter banks are therefore independent of the factorization methods used to compute them. These results cover the specification of user-defined whole-sample symmetric filter banks in Part 2 of the ISO JPEG 2000 standard.
The vortex free energy in the screening phase of the Z(2) Higgs model
International Nuclear Information System (INIS)
Meyer, H.
1983-06-01
The vortex free energy was proposed to distinguish between the confinement - and the Higgs phase (in the sense of 't Hooft) in lattice gauge theory, when matter fields are present that transform according to an arbitrary representation of the gauge group. In this paper I consider the Z(2) Higgs model and calculate the vortex free energy in the screening part of the confining/screening phase of Fradkin and Shenker. The result does not agree with the expected behavior that corresponds to the structure of the phase diagram. Therefore the vortex free energy is no longer a good indicator for confinement when matter fields transform nontrivially under the center of the gauge group (such as Z(2) Higgs scalars). (orig.)
Chaotic weak chimeras and their persistence in coupled populations of phase oscillators
International Nuclear Information System (INIS)
Bick, Christian; Ashwin, Peter
2016-01-01
Nontrivial collective behavior may emerge from the interactive dynamics of many oscillatory units. Chimera states are chaotic patterns of spatially localized coherent and incoherent oscillations. The recently-introduced notion of a weak chimera gives a rigorously testable characterization of chimera states for finite-dimensional phase oscillator networks. In this paper we give some persistence results for dynamically invariant sets under perturbations and apply them to coupled populations of phase oscillators with generalized coupling. In contrast to the weak chimeras with nonpositive maximal Lyapunov exponents constructed so far, we show that weak chimeras that are chaotic can exist in the limit of vanishing coupling between coupled populations of phase oscillators. We present numerical evidence that positive Lyapunov exponents can persist for a positive measure set of this inter-population coupling strength. (paper)
Two-color quark matter: U(1)A restoration, superfluidity, and quarkyonic phase
International Nuclear Information System (INIS)
Brauner, Tomas; Fukushima, Kenji; Hidaka, Yoshimasa
2009-01-01
We discuss the phase structure of quantum chromodynamics (QCD) with two colors and two flavors of light quarks. This is motivated by the increasing interest in the QCD phase diagram as follows: (1) The QCD critical point search has been under intensive dispute and its location and existence suffer from uncertainty of effective U(1) A symmetry restoration. (2) A new phase called quarkyonic matter is drawing theoretical and experimental attention but it is not clear whether it can coexist with diquark condensation. We point out that two-color QCD is nontrivial enough to contain essential ingredients for (1) and (2) both, and most importantly, is a system without the sign problem in numerical simulations on the lattice. We adopt the two-flavor Nambu-Jona-Lasinio model extended with the two-color Polyakov loop and make quantitative predictions that can be tested by lattice simulations.
Directory of Open Access Journals (Sweden)
J.L. Flanagan
2013-08-01
Full Text Available A vocoder technique is described in which speech signals are represented by their short-time phase and amplitude spectra. A complete transmission system utilizing this approach is simulated on a digital computer. The encoding method leads to an economy in transmission bandwidth and to a means for time compression and expansion of speech signals.
Quantum corrections to holographic mutual information
International Nuclear Information System (INIS)
Agón, Cesar A.; Faulkner, Thomas
2016-01-01
We compute the leading contribution to the mutual information (MI) of two disjoint spheres in the large distance regime for arbitrary conformal field theories (CFT) in any dimension. This is achieved by refining the operator product expansion method introduced by Cardy http://dx.doi.org/10.1088/1751-8113/46/28/285402. For CFTs with holographic duals the leading contribution to the MI at long distances comes from bulk quantum corrections to the Ryu-Takayanagi area formula. According to the FLM proposal http://dx.doi.org/10.1007/JHEP11(2013)074 this equals the bulk MI between the two disjoint regions spanned by the boundary spheres and their corresponding minimal area surfaces. We compute this quantum correction and provide in this way a non-trivial check of the FLM proposal.
Quantum corrections to holographic mutual information
Energy Technology Data Exchange (ETDEWEB)
Agón, Cesar A. [Martin Fisher School of Physics, Brandeis University,Waltham, MA 02453 (United States); Faulkner, Thomas [University of Illinois, Urbana-Champaign,Urbana, IL 61801-3080 (United States)
2016-08-22
We compute the leading contribution to the mutual information (MI) of two disjoint spheres in the large distance regime for arbitrary conformal field theories (CFT) in any dimension. This is achieved by refining the operator product expansion method introduced by Cardy http://dx.doi.org/10.1088/1751-8113/46/28/285402. For CFTs with holographic duals the leading contribution to the MI at long distances comes from bulk quantum corrections to the Ryu-Takayanagi area formula. According to the FLM proposal http://dx.doi.org/10.1007/JHEP11(2013)074 this equals the bulk MI between the two disjoint regions spanned by the boundary spheres and their corresponding minimal area surfaces. We compute this quantum correction and provide in this way a non-trivial check of the FLM proposal.
Diffractive generalized phase contrast for adaptive phase imaging and optical security
DEFF Research Database (Denmark)
Palima, Darwin; Glückstad, Jesper
2012-01-01
We analyze the properties of Generalized Phase Contrast (GPC) when the input phase modulation is implemented using diffractive gratings. In GPC applications for patterned illumination, the use of a dynamic diffractive optical element for encoding the GPC input phase allows for onthe- fly optimiza...... security applications and can be used to create phasebased information channels for enhanced information security....
Rule-based Information Integration
de Keijzer, Ander; van Keulen, Maurice
2005-01-01
In this report, we show the process of information integration. We specifically discuss the language used for integration. We show that integration consists of two phases, the schema mapping phase and the data integration phase. We formally define transformation rules, conversion, evolution and
Higgs phase in non-Abelian gauge theories
International Nuclear Information System (INIS)
Kaymakcalan, O.S.
1981-06-01
A non-Abelian gauge theory involving scalar fields with non-tachyonic mass terms in the Lagrangian is considered, in order to construct a finite energy density trial vacuum for this theory. The usual scalar potential arguments suggest that the vacuum of such a theory would be in the perturbative phase. However, the obvious choices for a vacuum in this phase, the Axial gauge and the Coulomb gauge bare vacua, do not have finite energy densities even with an ultraviolet cutoff. Indeed, it is a non-trivial problem to construct finite energy density vacua for non-Abelian gauge theories and this is intimately connected with the gauge fixing degeneracies of these theories. Since the gauge fixing is achieved in the Unitary gauge, this suggests that the Unitary gauge bare vacuum might be a finite energy trial vacuum and, despite the form of the scalar potential, the vacuum of this theory might be in a Higgs phase rather than the perturbative phase
DEFF Research Database (Denmark)
Larsson, Magnus; Segerstéen, Solveig; Svensson, Cathrin
2011-01-01
leaders on the basis of their possession of reliable knowledge in technical as well as organizational domains. The informal leaders engaged in interpretation and brokering of information and knowledge, as well as in mediating strategic values and priorities on both formal and informal arenas. Informal...... leaders were thus seen to function on the level of the organization as a whole, and in cooperation with formal leaders. Drawing on existing theory of leadership in creative and professional contexts, this cooperation can be specified to concern task structuring. The informal leaders in our study...... contributed to task structuring through sensemaking activities, while formal leaders focused on aspects such as clarifying output expectations, providing feedback, project structure, and diversity....
International Nuclear Information System (INIS)
Mogaddam, Mehran Wahdani; Shuvalov, Vladimir V
2005-01-01
The dynamics of formation of a nonlinear response of a double phase-conjugate (PC) BaTiO 3 mirror is calculated. It is shown that because of competition between processes of different types (related to the presence of several PC channels, the local and nonlocal components of the photorefractive nonlinearity), the transient and dynamic lasing regimes for this mirror can be substantially different. It is found that the development of lasing begins with the successive formation and phasing of dynamic holograms of two different types (two PC channels). It is shown that even under optimal conditions, the lasing regime is not stationary due to competition between processes of different types, and the parameters of output fields fluctuate in time in a nontrivial way (due to the presence of the in-phase and out-of-phase components). Several scenarios of transition to the dynamic chaos are described. (nonlinear optical phenomena)
Johnson, Miriam J; Booth, Sara; Currow, David C; Lam, Lawrence T; Phillips, Jane L
2016-05-01
The handheld fan is an inexpensive and safe way to provide facial airflow, which may reduce the sensation of chronic refractory breathlessness, a frequently encountered symptom. To test the feasibility of developing an adequately powered, multicenter, multinational randomized controlled trial comparing the efficacy of a handheld fan and exercise advice with advice alone in increasing activity in people with chronic refractory breathlessness from a variety of medical conditions, measuring recruitment rates; data quality; and potential primary outcome measures. This was a Phase II, multisite, international, parallel, nonblinded, mixed-methods randomized controlled trial. Participants were centrally randomized to fan or control. All received breathlessness self-management/exercise advice and were followed up weekly for four weeks. Participants/carers were invited to participate in a semistructured interview at the study's conclusion. Ninety-seven people were screened, 49 randomized (mean age 68 years; 49% men), and 43 completed the study. Site recruitment varied from 0.25 to 3.3/month and screening:randomization from 1.1:1 to 8.5:1. There were few missing data except for the Chronic Obstructive Pulmonary Disease Self-Efficacy Scale (two-thirds of data missing). No harms were observed. Three interview themes included 1) a fan is a helpful self-management strategy, 2) a fan aids recovery, and 3) a symptom control trial was welcome. A definitive, multisite trial to study the use of the handheld fan as part of self-management of chronic refractory breathlessness is feasible. Participants found the fan useful. However, the value of information for changing practice or policy is unlikely to justify the expense of such a trial, given perceived benefits, the minimal costs, and an absence of harms demonstrated in this study. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Compact, common path quantitative phase microscopic techniques ...
Indian Academy of Sciences (India)
2014-01-05
refractive index information as a change in intensity). ... phase imaging method which provides information about the optical thickness of live .... index values of the material of the glass bead and the surrounding medium was ...
Understanding Interdependency Through Complex Information Sharing
Directory of Open Access Journals (Sweden)
Fernando Rosas
2016-01-01
Full Text Available The interactions between three or more random variables are often nontrivial, poorly understood and, yet, are paramount for future advances in fields such as network information theory, neuroscience and genetics. In this work, we analyze these interactions as different modes of information sharing. Towards this end, and in contrast to most of the literature that focuses on analyzing the mutual information, we introduce an axiomatic framework for decomposing the joint entropy that characterizes the various ways in which random variables can share information. Our framework distinguishes between interdependencies where the information is shared redundantly and synergistic interdependencies where the sharing structure exists in the whole, but not between the parts. The key contribution of our approach is to focus on symmetric properties of this sharing, which do not depend on a specific point of view for differentiating roles between its components. We show that our axioms determine unique formulas for all of the terms of the proposed decomposition for systems of three variables in several cases of interest. Moreover, we show how these results can be applied to several network information theory problems, providing a more intuitive understanding of their fundamental limits.
CHARACTERIZATION OF PHASES IN SECONDARY AlZn10Si8Mg CAST ALLOY
Directory of Open Access Journals (Sweden)
Eva Tillová
2011-04-01
Full Text Available Using recycled aluminium cast alloys is profitable in many aspects. Requiring only 5 % of the energy to produce secondary metal as compared to primary metal and generates only 5 % of the green house gas emissions, the recycling of aluminium is therefore beneficial of both environmental and economical point of view. Secondary AlZn10Si8Mg (UNIFONT® - 90 cast alloy are used for engine and vehicle constructions, hydraulic unit and mouldmaking without heat treatment. Properties include good castability, very good mechanical strength and elongation, light weight, good wear resistance, low thermal expansion and very good machining. Improved mechanical properties are strongly dependent upon the morphologies, type and distribution of the secondary phases, which are in turn a function of alloy composition and cooling rate. The presence of additional elements as Mg, Mn, Fe, or Cu allows many complex intermetallic phases to form, which make characterisation non-trivial. These include, for example, Mg2Si, Al2CuMg and AlFeMn phases, all of which may have some solubility for additional elements. Phase’s identification in aluminium alloys is often non-trivial due to the fact that some of the phases have either similar crystal structures or only subtle changes in their chemistries. A combination different analytical techniques (light microscopy upon black-white and colour etching, scanning electron microscopy (SEM upon deep etching, energy dispersive X-ray analysis (EDX and HV 0.01 microhardness measurement were therefore been used for the identification of the various phase.
On the role of spatial phase and phase correlation in vision, illusion, and cognition
Gladilin, Evgeny; Eils, Roland
2015-01-01
Numerous findings indicate that spatial phase bears an important cognitive information. Distortion of phase affects topology of edge structures and makes images unrecognizable. In turn, appropriately phase-structured patterns give rise to various illusions of virtual image content and apparent motion. Despite a large body of phenomenological evidence not much is known yet about the role of phase information in neural mechanisms of visual perception and cognition. Here, we are concerned with a...
On the role of spatial phase and phase correlation in vision, illusion and cognition
Evgeny eGladilin; Roland eEils; Roland eEils
2015-01-01
Numerous findings indicate that spatial phase bears an important cognitive information. Distortion of phase affects topology of edge structures and makes images unrecognizable. In turn, appropriately phase-structured patterns give rise to various illusions of virtual image content and apparent motion. Despite a large body of phenomenological evidence not much is known yet about the role of phase information in neural mechanisms of visual perception and cognition. Here, we are concerned with a...
Rényi entropy measure of noise-aided information transmission in a binary channel.
Chapeau-Blondeau, François; Rousseau, David; Delahaies, Agnès
2010-05-01
This paper analyzes a binary channel by means of information measures based on the Rényi entropy. The analysis extends, and contains as a special case, the classic reference model of binary information transmission based on the Shannon entropy measure. The extended model is used to investigate further possibilities and properties of stochastic resonance or noise-aided information transmission. The results demonstrate that stochastic resonance occurs in the information channel and is registered by the Rényi entropy measures at any finite order, including the Shannon order. Furthermore, in definite conditions, when seeking the Rényi information measures that best exploit stochastic resonance, then nontrivial orders differing from the Shannon case usually emerge. In this way, through binary information transmission, stochastic resonance identifies optimal Rényi measures of information differing from the classic Shannon measure. A confrontation of the quantitative information measures with visual perception is also proposed in an experiment of noise-aided binary image transmission.
Risks, Information and Short-Run Timber Supply
Directory of Open Access Journals (Sweden)
Francesca Rinaldi
2013-12-01
Full Text Available Efforts to increase wood mobilization have highlighted the need to appraise drivers of short-run timber supply. The current study aims to shed further light on harvesting decisions of private forest owners, by investigating optimal harvesting under uncertainty, when timber revenues are invested on financial markets and uncertainty is mitigated by news releases. By distinguishing between aggregate economic risk and sector specific risks, the model studies in great detail optimal harvesting-investment decisions, with particular emphasis on the non-trivial transmission of risk on optimal harvesting, and on the way private forest owners react to news and information. The analysis of the role played by information in harvesting decisions is a novelty in forest economic theory. The presented model is highly relevant from a policy—information is a commonly used forest policy instrument—as well as a practical perspective, since the mechanism of risk transmission is at the basis of timber pricing.
Information Space, Information Field, Information Environment
Directory of Open Access Journals (Sweden)
Victor Ya. Tsvetkov
2014-08-01
Full Text Available The article analyzes information space, information field and information environment; shows that information space can be natural and artificial; information field is substantive and processual object and articulates the space property; information environment is concerned with some object and acts as the surrounding in relation to it and is considered with regard to it. It enables to define information environment as a subset of information space. It defines its passive description. Information environment can also be defined as a subset of information field. It corresponds to its active description.
Energy Technology Data Exchange (ETDEWEB)
Gulminelli, F
2003-05-01
In this work the general theory of first order phase transitions in finite systems is discussed, with a special emphasis to the conceptual problems linked to a thermodynamic description for small, short-lived systems de-exciting in the vacuum as nuclear samples coming from heavy ion collisions. After a short review of the general theory of phase transitions in the framework of information theory; we will present the different possible extensions to the field of finite systems. The concept of negative heat capacity, developed in the early seventies in the context of self-gravitating systems, will be reinterpreted in the general framework of convexity anomalies of thermo-statistical potentials. The connection with the distribution of the order parameter will lead us to a definition of first order phase transitions in finite systems based on topology anomalies of the event distribution in the space of observations. A careful study of the thermodynamic limit will provide a bridge with the standard theory of phase transitions and show that in a wide class of physical situations the different statistical ensembles are irreducibly inequivalent. In the second part of the paper we will apply the theoretical ideas developed in the first part to the possible observation of a liquid-to-gas-like phase transition in heavy ion collisions. The applicability of equilibrium concepts in a dynamical collisional process without boundary conditions will first be critically discussed. The observation of abnormally large partial energy fluctuations in carefully selected samples of collisions detected with the MULTICS-Miniball array will then be reported as a strong evidence of a first order phase transition with negative heat capacity in the nuclear equation of state. (author)
Two applications of Berry's phase in fermionic field theory
International Nuclear Information System (INIS)
Goff, W.E.
1989-01-01
When quantized fermions are coupled to a background field, nontrivial effects may arise due to the geometry and/or topology of the space of background field configurations. In this thesis, two examples of Berry's geometrical phase in a fermionic sea are studied: the anomalous commutator in gauge field theory and the intrinsic orbital angular momentum in superfluid 3 He-A. Chapter 1 is a brief introduction. Chapter 2 reviews Berry's Phase and several toy models. Effective actions are calculated for two models in gradient expansions and the role of a geometric term is discussed. Chapter 3 investigates the anomalous commutator in the generators of gauge symmetry in field theory. Using an idea introduced by Sonoda, the Berry phase of the vacuum state is found to be the sum of the Berry phases of the individual states in the sea plus a piece due to the infinite nature of the Dirac sea. The latter is the anomalous commutator. Also found is a relative minus sign between the commutator of the total gauge symmetry generators and the commutator of the fermionic charge generators. Examples are given. In Chapter 4, a geometric way of deriving the intrinsic orbital angular momentum term in the 3 He-A equations of motion is presented. Homogeneous, adiabatically evolving textures at zero temperature are found to pick up a nonzero groundstate Berry phase, where the ground state is taken to be a filled sea of Bogoliubov quasiparticles. Interpreting the phase as a Wess-Zumino effective action for the condensate provides a geometric origin for the intrinsic angular momentum. The idea of a ground-state phase is then extended to other gap functions and a more general result is obtained. Chapter 5 concludes with a discussion of the possibility of unifying the two problems in a more general framework and directions for further work
Strain-induced topological magnon phase transitions: applications to kagome-lattice ferromagnets
Owerre, S. A.
2018-06-01
A common feature of topological insulators is that they are characterized by topologically invariant quantity such as the Chern number and the index. This quantity distinguishes a nontrivial topological system from a trivial one. A topological phase transition may occur when there are two topologically distinct phases, and it is usually defined by a gap closing point where the topologically invariant quantity is ill-defined. In this paper, we show that the magnon bands in the strained (distorted) kagome-lattice ferromagnets realize an example of a topological magnon phase transition in the realistic parameter regime of the system. When spin–orbit coupling (SOC) is neglected (i.e. no Dzyaloshinskii–Moriya interaction), we show that all three magnon branches are dispersive with no flat band, and there exists a critical point where tilted Dirac and semi-Dirac point coexist in the magnon spectra. The critical point separates two gapless magnon phases as opposed to the usual phase transition. Upon the inclusion of SOC, we realize a topological magnon phase transition point at the critical strain , where D and J denote the perturbative SOC and the Heisenberg spin exchange interaction respectively. It separates two distinct topological magnon phases with different Chern numbers for and for . The associated anomalous thermal Hall conductivity develops an abrupt change at , due to the divergence of the Berry curvature in momentum space. The proposed topological magnon phase transition is experimentally feasible by applying external perturbations such as uniaxial strain or pressure.
Unconventional spin texture of a topologically nontrivial semimetal Sb(110)
DEFF Research Database (Denmark)
Strózecka, A.; Eiguren, A.; Bianchi, Marco
2012-01-01
The surfaces of antimony are characterized by the presence of spin-split states within the projected bulk band gap and the Fermi contour is thus expected to exhibit a spin texture. Using spin-resolved density functional theory calculations, we determine the spin polarization of the surface bands...... signal.We identify the allowed scattering vectors and analyze their bias evolution in relation to the surface-state dispersion....
Non-trivial pursuit - new approaches to Nordic deliciousness
DEFF Research Database (Denmark)
Evans, Joshua David
2012-01-01
Nordic Food Lab was founded in 2008 as a research and development lab with the purpose of exploring food in the Nordic region. Chef René Redzepi and gastronomic entrepreneur Claus Meyer, co-owners of the restaurant Noma in Copenhagen, realised this investigation could not be undertaken...... in the restaurant kitchen alone. What they needed was a space where chefs, scientists, and other researchers could come together to investigate raw materials, traditional processes, and modern techniques more deeply than the pressure of daily service would allow....
Multiplicity of nontrivial solutions for elliptic equations with ...
Indian Academy of Sciences (India)
3Department of Mathematics, National Technical University, Zografou Campus, ... For concrete applications we refer to the book of Naniewicz and ...... [24] Lebourg G, Valeur mayenne pour gradient gén`eralisé, CRAS Paris 281 (1975) 795– ...
Non-Euclidean Geometry, Nontrivial Topology and Quantum Vacuum Effects
Directory of Open Access Journals (Sweden)
Yurii A. Sitenko
2018-01-01
Full Text Available Space out of a topological defect of the Abrikosov–Nielsen–Olesen (ANO vortex type is locally flat but non-Euclidean. If a spinor field is quantized in such a space, then a variety of quantum effects are induced in the vacuum. On the basis of the continuum model for long-wavelength electronic excitations originating in the tight-binding approximation for the nearest-neighbor interaction of atoms in the crystal lattice, we consider quantum ground-state effects in Dirac materials with two-dimensional monolayer structures warped into nanocones by a disclination; the nonzero size of the disclination is taken into account, and a boundary condition at the edge of the disclination is chosen to ensure self-adjointness of the Dirac–Weyl Hamiltonian operator. We show that the quantum ground-state effects are independent of the disclination size, and we find circumstances in which they are independent of parameters of the boundary condition.
High-order noise filtering in nontrivial quantum logic gates
CSIR Research Space (South Africa)
Green, T
2012-07-01
Full Text Available composed of arbitrary control sequences. We present a general method to calculate the ensemble-averaged entanglement fidelity to arbitrary order in terms of noise filter functions, and provide explicit expressions to fourth order in the noise strength...
The Cherenkov Radiation for Non-Trivial Systems
International Nuclear Information System (INIS)
Grau Carles, A.
2002-01-01
The charge pathways and the dielectric properties of the medium are two essential aspects to be considered in the study of the emission of Cherenkov radiation. We described the evolution of the Cherenkov wavefront when the charges follow circular or helical pathways. Also we derive expressions for the refractive Index in different transparent media (solid, liquid or gas), focusing our attention on optically active plasmas. The optical analogies between the plasma and the birefringent crystals is studied in detail. Finally, we list some examples of plasmas, which can be considered emitters of Cherenkov radiation. (Author) 52 refs
Nontrivial topological states on a Möbius band
Beugeling, W.; Quelle, A.; Morais Smith, C.
2014-01-01
In the field of topological insulators, the topological properties of quantum states in samples with simple geometries, such as a cylinder or a ribbon, have been classified and understood during the past decade. Here we extend these studies to a Möbius band and argue that its lack of orientability
Selecting and Using Mathematics Methods Texts: Nontrivial Tasks
Harkness, Shelly Sheats; Brass, Amy
2017-01-01
Mathematics methods textbooks/texts are important components of many courses for preservice teachers. Researchers should explore how these texts are selected and used. Within this paper we report the findings of a survey administered electronically to 132 members of the Association of Mathematics Teacher Educators (AMTE) in order to answer the…
Interplay between cost and benefits triggers nontrivial vaccination uptake
Steinegger, Benjamin; Cardillo, Alessio; Rios, Paolo De Los; Gómez-Gardeñes, Jesús; Arenas, Alex
2018-03-01
The containment of epidemic spreading is a major challenge in science. Vaccination, whenever available, is the best way to prevent the spreading, because it eventually immunizes individuals. However, vaccines are not perfect, and total immunization is not guaranteed. Imperfect immunization has driven the emergence of antivaccine movements that totally alter the predictions about the epidemic incidence. Here, we propose a mathematically solvable mean-field vaccination model to mimic the spontaneous adoption of vaccines against influenzalike diseases and the expected epidemic incidence. The results are in agreement with extensive Monte Carlo simulations of the epidemics and vaccination coevolutionary processes. Interestingly, the results reveal a nonmonotonic behavior on the vaccination coverage that increases with the imperfection of the vaccine and after decreases. This apparent counterintuitive behavior is analyzed and understood from stability principles of the proposed mathematical model.
International Nuclear Information System (INIS)
Qi, Jingshan; Li, Xiao; Qian, Xiaofeng
2016-01-01
Electrically controlled band gap and topological electronic states are important for the next-generation topological quantum devices. In this letter, we study the electric field control of band gap and topological phase transitions in multilayer germanane. We find that although the monolayer and multilayer germananes are normal insulators, a vertical electric field can significantly reduce the band gap of multilayer germananes owing to the giant Stark effect. The decrease of band gap eventually leads to band inversion, transforming them into topological insulators with nontrivial Z_2 invariant. The electrically controlled topological phase transition in multilayer germananes provides a potential route to manipulate topologically protected edge states and design topological quantum devices. This strategy should be generally applicable to a broad range of materials, including other two-dimensional materials and ultrathin films with controlled growth.
A non-classical phase diagram for virus-bacterial co-evolution mediated by CRISPR
Han, Pu; Deem, Michael
CRISPR is a newly discovered prokaryotic immune system. Bacteria and archaea with this system incorporate genetic material from invading viruses into their genomes, providing protection against future infection by similar viruses. Due to the cost of CRISPR, bacteria can lose the acquired immunity. We will show an intriguing phase diagram of the virus extinction probability, which when the rate of losing the acquired immunity is small, is more complex than that of the classic predator-prey model. As the CRISPR incorporates genetic material, viruses are under pressure to evolve to escape the recognition by CRISPR, and this co-evolution leads to a non-trivial phase structure that cannot be explained by the classical predator-prey model.
Boundary induced phase transition with stochastic entrance and exit
International Nuclear Information System (INIS)
Mitra, Mithun Kumar; Chatterjee, Sakuntala
2014-01-01
We study an open-chain totally asymmetric exclusion process (TASEP) with stochastic gates present at the two boundaries. The gating dynamics has been modeled with the physical system of ion-channel gating in mind. These gates can randomly switch between an open state and a closed state. In the open state, the gates are highly permeable such that any particle arriving at the gate immediately passes through. In the closed state, a particle becomes trapped at the gate and cannot pass through until the gate switches open again. We calculate the phase-diagram of the system and find important and non-trivial differences with the phase-diagram of a regular open-chain TASEP. In particular, depending on the switching rates of the two gates, the system may or may not admit a maximal current phase. Our analytic calculations within mean-field theory capture the main qualitative features of our Monte Carlo simulation results. We also perform a refined mean-field calculation where the correlations at the boundaries are taken into account. This theory shows significantly better quantitative agreement with our simulation results. (paper)
Phase behavior of charged colloids on spherical surfaces
Kelleher, Colm; Guerra, Rodrigo; Chaikin, Paul
For a broad class of 2D materials, the transition from isotropic fluid to crystalline solid is described by the theory of melting due to Kosterlitz, Thouless, Halperin, Nelson and Young. According to this theory, long-range order is achieved via elimination of the topological defects which proliferate in the fluid phase. However, many natural and man-made 2D systems posses spatial curvature and/or non-trivial topology, which require the presence of defects, even at T = 0 . In principle, the presence of these defects could profoundly affect the phase behavior of such a system. In this presentation, we describe experiments and simulations we have performed on repulsive particles which are bound to the surface of a sphere. We observe spatial structures and inhomogeneous dynamics that cannot be captured by the measures traditionally used to describe flat-space phase behavior. We show that ordering is achieved by a novel mechanism: sequestration of topological defects into freely-terminating grain boundaries (``scars''), and simultaneous spatial organization of the scars themselves on the vertices of an icosahedron. The emergence of icosahedral order coincides with the localization of mobility into isolated ``lakes'' of fluid or glassy particles, situated at the icosahedron vertices.
Glare Spot Phase Doppler Anemometry
Hespel, Camille; Ren, Kuan Fang; Gréhan, Gérard; Onofri, Fabrice
2006-01-01
International audience; The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index is also necessary since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemo...
Nanoscale phase change memory materials.
Caldwell, Marissa A; Jeyasingh, Rakesh Gnana David; Wong, H-S Philip; Milliron, Delia J
2012-08-07
Phase change memory materials store information through their reversible transitions between crystalline and amorphous states. For typical metal chalcogenide compounds, their phase transition properties directly impact critical memory characteristics and the manipulation of these is a major focus in the field. Here, we discuss recent work that explores the tuning of such properties by scaling the materials to nanoscale dimensions, including fabrication and synthetic strategies used to produce nanoscale phase change memory materials. The trends that emerge are relevant to understanding how such memory technologies will function as they scale to ever smaller dimensions and also suggest new approaches to designing materials for phase change applications. Finally, the challenges and opportunities raised by integrating nanoscale phase change materials into switching devices are discussed.
Phase-sensitive flow cytometer
Energy Technology Data Exchange (ETDEWEB)
Steinkamp, J.A.
1992-12-31
This report describes phase-sensitive flow cytometer (FCM) which provides additional FCM capability to use the fluorescence lifetime of one or more fluorochromes bound to single cells to provide additional information regarding the cells. The resulting fluorescence emission can be resolved into individual fluorescence signals if two fluorochromes are present or can be converted directly to a decay lifetime from a single fluorochrome. The excitation light for the fluorochromes is modulated to produce an amplitude modulated fluorescence pulse as the fluorochrome is excited in the FCM. The modulation signal also forms a reference signal that is phase-shifted a selected amount for subsequent mixing with the output modulated fluorescence intensity signal in phase-sensitive detection circuitry. The output from the phase-sensitive circuitry is then an individual resolved fluorochrome signal or a single fluorochrome decay lifetime, depending on the applied phase shifts.
Phase transition in finite systems
International Nuclear Information System (INIS)
Chomaz, Ph.; Duflot, V.; Duflot, V.; Gulminelli, F.
2000-01-01
In this paper we present a review of selected aspects of Phase transitions in finite systems applied in particular to the liquid-gas phase transition in nuclei. We show that the problem of the non existence of boundary conditions can be solved by introducing a statistical ensemble with an averaged constrained volume. In such an ensemble the microcanonical heat capacity becomes negative in the transition region. We show that the caloric curve explicitly depends on the considered transformation of the volume with the excitation energy and so does not bear direct informations on the characteristics of the phase transition. Conversely, partial energy fluctuations are demonstrated to be a direct measure of the equation of state. Since the heat capacity has a negative branch in the phase transition region, the presence of abnormally large kinetic energy fluctuations is a signal of the liquid gas phase transition. (author)
Fundamentals of ultrasonic phased arrays
Schmerr, Lester W
2014-01-01
This book describes in detail the physical and mathematical foundations of ultrasonic phased array measurements.?The book uses linear systems theory to develop a comprehensive model of the signals and images that can be formed with phased arrays. Engineers working in the field of ultrasonic nondestructive evaluation (NDE) will find in this approach a wealth of information on how to design, optimize and interpret ultrasonic inspections with phased arrays. The fundamentals and models described in the book will also be of significant interest to other fields, including the medical ultrasound and
Communication complexity and information complexity
Pankratov, Denis
Information complexity enables the use of information-theoretic tools in communication complexity theory. Prior to the results presented in this thesis, information complexity was mainly used for proving lower bounds and direct-sum theorems in the setting of communication complexity. We present three results that demonstrate new connections between information complexity and communication complexity. In the first contribution we thoroughly study the information complexity of the smallest nontrivial two-party function: the AND function. While computing the communication complexity of AND is trivial, computing its exact information complexity presents a major technical challenge. In overcoming this challenge, we reveal that information complexity gives rise to rich geometrical structures. Our analysis of information complexity relies on new analytic techniques and new characterizations of communication protocols. We also uncover a connection of information complexity to the theory of elliptic partial differential equations. Once we compute the exact information complexity of AND, we can compute exact communication complexity of several related functions on n-bit inputs with some additional technical work. Previous combinatorial and algebraic techniques could only prove bounds of the form theta( n). Interestingly, this level of precision is typical in the area of information theory, so our result demonstrates that this meta-property of precise bounds carries over to information complexity and in certain cases even to communication complexity. Our result does not only strengthen the lower bound on communication complexity of disjointness by making it more exact, but it also shows that information complexity provides the exact upper bound on communication complexity. In fact, this result is more general and applies to a whole class of communication problems. In the second contribution, we use self-reduction methods to prove strong lower bounds on the information
Phase sensitive multichannel OCT
International Nuclear Information System (INIS)
Trasischker, W.
2015-01-01
The main aim of this thesis was to develop and improve phase sensitive, multichannel methods for optical coherence tomography (OCT) using light in the 840 nm and 1040 nm regime. Conventional OCT provides purely structural information by illuminating the sample by one beam and recording the backscattered signal with one detection channel. Combination of this approach with a raster scan enables the acquisition of 2D and 3D structural information with a resolution in the micrometer regime. However, sometimes additional image contrast or information is desired. Amongst other approaches, this can be provided by a phase sensitive analysis of the interference pattern. Combining phase sensitivity with the illumination of the sample by more than one beam and/or by recording the data using more than one data acquisition channel allows for even more enhanced imaging. While phase sensitive OCT gives access to additional contrast and information, multichannel OCT can provide higher imaging speed, scan eld size and exible dierential measurements. Amongst the dierential, phase sensitive approaches, Doppler OCT (DOCT) and polarization sensitive OCT (PS-OCT) are two of the most promising OCT modalities. While the former targets information on the movement of backscattering particles, the latter measures alterations of the polarization state of the light induced by the sample. Both techniques provide additional image contrast and are, due to the non-invasive and fast character of OCT, well suited for in vivo imaging of the human eye. In the course of this thesis, two dierent multichannel, phase sensitive OCT systems will be presented. First, a D-OCT system with three dierent sampling beams is described. With a central wavelength of 840 nm these three beams are emitted by three individual laser sources. This eectively eliminates any cross talk and provides the full depth range for each channel. Furthermore, by illuminating the sample from three dierent directions, the absolute
Phase diagrams of exceptional and supersymmetric lattice gauge theories
Energy Technology Data Exchange (ETDEWEB)
Wellegehausen, Bjoern-Hendrik
2012-07-10
In this work different strongly-coupled gauge theories with and without fundamental matter have been studied on the lattice with an emphasis on the confinement problem and the QCD phase diagram at nonvanishing net baryon density as well as on possible supersymmetric extensions of the standard model of particle physics. In gauge theories with a non-trivial centre symmetry, as for instance SU(3)-Yang-Mills theory, confinement is intimately related to the centre of the gauge group, and the Polyakov loop serves as an order parameter for confinement. In QCD, this centre symmetry is explicitly broken by quarks in the fundamental representation of the gauge group. But still quarks and gluons are confined in mesons, baryons and glueballs at low temperatures and small densities, suggesting that centre symmetry is not responsible for the phenomenon of confinement. Therefore it is interesting to study pure gauge theories without centre symmetry. In this work this has been done by replacing the gauge group SU(3) of the strong interaction with the exceptional Lie group G{sub 2}, that has a trivial centre. To investigate G{sub 2} gauge theory on the lattice, a new and highly efficient update algorithm has been developed, based on a local HMC algorithm. Employing this algorithm, the proposed and already investigated first order phase transition from a confined to a deconfined phase has been confirmed, showing that indeed a first order phase transition without symmetry breaking or an order parameter is possible. In this context, also the deconfinement phase transition of the exceptional Lie groups F4 and E6 in three spacetime dimensions has been studied. It has been shown that both theories also possess a first order phase transition.
Phase diagrams of exceptional and supersymmetric lattice gauge theories
International Nuclear Information System (INIS)
Wellegehausen, Bjoern-Hendrik
2012-01-01
In this work different strongly-coupled gauge theories with and without fundamental matter have been studied on the lattice with an emphasis on the confinement problem and the QCD phase diagram at nonvanishing net baryon density as well as on possible supersymmetric extensions of the standard model of particle physics. In gauge theories with a non-trivial centre symmetry, as for instance SU(3)-Yang-Mills theory, confinement is intimately related to the centre of the gauge group, and the Polyakov loop serves as an order parameter for confinement. In QCD, this centre symmetry is explicitly broken by quarks in the fundamental representation of the gauge group. But still quarks and gluons are confined in mesons, baryons and glueballs at low temperatures and small densities, suggesting that centre symmetry is not responsible for the phenomenon of confinement. Therefore it is interesting to study pure gauge theories without centre symmetry. In this work this has been done by replacing the gauge group SU(3) of the strong interaction with the exceptional Lie group G 2 , that has a trivial centre. To investigate G 2 gauge theory on the lattice, a new and highly efficient update algorithm has been developed, based on a local HMC algorithm. Employing this algorithm, the proposed and already investigated first order phase transition from a confined to a deconfined phase has been confirmed, showing that indeed a first order phase transition without symmetry breaking or an order parameter is possible. In this context, also the deconfinement phase transition of the exceptional Lie groups F4 and E6 in three spacetime dimensions has been studied. It has been shown that both theories also possess a first order phase transition.
Verma, Surender; Bhardwaj, Shankita
2018-05-01
We have investigated a possible connection between the Majorana phases and geometric parameters of Majorana unitarity triangle (MT) in two-texture zero neutrino mass matrix. Such analytical relations can, also, be obtained for other theoretical models viz. hybrid textures, neutrino mass matrix with vanishing minors and have profound implications for geometric description of C P violation. As an example, we have considered the two-texture zero neutrino mass model to obtain a relation between Majorana phases and MT parameters that may be probed in various lepton number violating processes. In particular, we find that Majorana phases depend on only one of the three interior angles of the MT in each class of two-texture zero neutrino mass matrix. We have also constructed the MT for class A , B , and C neutrino mass matrices. Nonvanishing areas and nontrivial orientations of these Majorana unitarity triangles indicate nonzero C P violation as a generic feature of this class of mass models.
Böhm, Arno; Koizumi, Hiroyasu; Niu, Qian; Zwanziger, Joseph
2003-01-01
Aimed at graduate physics and chemistry students, this is the first comprehensive monograph covering the concept of the geometric phase in quantum physics from its mathematical foundations to its physical applications and experimental manifestations It contains all the premises of the adiabatic Berry phase as well as the exact Anandan-Aharonov phase It discusses quantum systems in a classical time-independent environment (time dependent Hamiltonians) and quantum systems in a changing environment (gauge theory of molecular physics) The mathematical methods used are a combination of differential geometry and the theory of linear operators in Hilbert Space As a result, the monograph demonstrates how non-trivial gauge theories naturally arise and how the consequences can be experimentally observed Readers benefit by gaining a deep understanding of the long-ignored gauge theoretic effects of quantum mechanics and how to measure them
Topological phases of interacting fermions in one-dimensional superconductor - normal metal geometry
Energy Technology Data Exchange (ETDEWEB)
Meidan, Dganit [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universitaet Berlin, 14195 Berlin (Germany); Romito, Alessandro; Brouwer, Piet W. [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)
2015-07-01
One-dimensional superconductors can be in non-trivial topological phases harboring Majorana end-states, which possess non-abelian statistics. It has been recently established that in the presence of interactions the classification of topological superconducting phases can be significantly altered. Specifically, for one-dimensional superconductors possessing a time reversal symmetry (BDI class), interactions reduce the infinitely many non-interacting phases (Z topological index) to eight distinct ones (Z{sub 8} topological index). In this talk I will consider multi-mode superconducting wires in such BDI class when probed by an external contact, and discuss their low temperature and voltage bias transport properties. I will first show that the Andreev reflection component of the scattering matrix of the probing lead provides a topological index, r=-4,.., 4, which distinguish the eight topological phases. The two topologically equivalent phases with r= 4,-4 support emergent many-body end states, which are identified to be a topologically protected Kondo-like resonance. The path in phase space that connects these equivalent phases crosses a non-fermi liquid fixed point where a multiple channel Kondo effect develops.
Selected cerium phase diagrams
International Nuclear Information System (INIS)
Gschneidner, K.A. Jr.; Verkade, M.E.
1974-09-01
A compilation of cerium alloy phase equilibria data based on the most reliable information available is presented. The binary systems selected are those of cerium with each of the following twenty nine elements which might be commonly found in steels: Al, Sb, As, Bi, Ca, C, Cr, Co, Nb, Cu, Fe, Pb, Mg, Mn, Mo, Ni, N, O, P, Se, Si, Ag, S, Te, Sn, Ti, W, and Zn. A brief discussion, a summary of crystal lattice parameters where applicable, and a list of references is included for each element surveyed. (U.S.)
Ricks, Wendell; Corker, Kevin
1990-01-01
Primary Flight Display (PFD) information management and cockpit display of information management research is presented in viewgraph form. The information management problem in the cockpit, information management burdens, the key characteristics of an information manager, the interface management system handling the flow of information and the dialogs between the system and the pilot, and overall system architecture are covered.
Final Report: Sensorpedia Phase 3
Energy Technology Data Exchange (ETDEWEB)
Gorman, Bryan L [ORNL; Resseguie, David R [ORNL
2011-02-01
This report is a summary of the Oak Ridge National Laboratory s (ORNL s) Phase 3 development of Sensorpedia, a sensor information sharing platform. Sensorpedia is ORNL s Wikipedia for Sensors. The overall goal of Sensorpedia is to enable global scale sensor information sharing for scientific research, national security and defense, public health and safety, emergency preparedness and response, and general community awareness and outreach.
Aligning business processes and information systems new approaches to continuous quality engineering
Heinrich, Robert
2014-01-01
Business processes and information systems mutually affect each other in non-trivial ways. Frequently, processes are designed without taking the systems' impact into account, and vice versa. Missing alignment at design-time results in quality problems at run-time. Robert Heinrich gives examples from research and practice for an integrated design of process and system quality. A quality reference-model characterizes process quality and a process notation is extended to operationalize the model. Simulation is a powerful means to predict the mutual quality impact, to compare design alternatives,
Higher-order phase transitions on financial markets
Kasprzak, A.; Kutner, R.; Perelló, J.; Masoliver, J.
2010-08-01
Statistical and thermodynamic properties of the anomalous multifractal structure of random interevent (or intertransaction) times were thoroughly studied by using the extended continuous-time random walk (CTRW) formalism of Montroll, Weiss, Scher, and Lax. Although this formalism is quite general (and can be applied to any interhuman communication with nontrivial priority), we consider it in the context of a financial market where heterogeneous agent activities can occur within a wide spectrum of time scales. As the main general consequence, we found (by additionally using the Saddle-Point Approximation) the scaling or power-dependent form of the partition function, Z(q'). It diverges for any negative scaling powers q' (which justifies the name anomalous) while for positive ones it shows the scaling with the general exponent τ(q'). This exponent is the nonanalytic (singular) or noninteger power of q', which is one of the pilar of higher-order phase transitions. In definition of the partition function we used the pausing-time distribution (PTD) as the central one, which takes the form of convolution (or superstatistics used, e.g. for describing turbulence as well as the financial market). Its integral kernel is given by the stretched exponential distribution (often used in disordered systems). This kernel extends both the exponential distribution assumed in the original version of the CTRW formalism (for description of the transient photocurrent measured in amorphous glassy material) as well as the Gaussian one sometimes used in this context (e.g. for diffusion of hydrogen in amorphous metals or for aging effects in glasses). Our most important finding is the third- and higher-order phase transitions, which can be roughly interpreted as transitions between the phase where high frequency trading is most visible and the phase defined by low frequency trading. The specific order of the phase transition directly depends upon the shape exponent α defining the stretched
Universal scattering response across the type-II Weyl semimetal phase diagram
Rüßmann, P.; Weber, A. P.; Glott, F.; Xu, N.; Fanciulli, M.; Muff, S.; Magrez, A.; Bugnon, P.; Berger, H.; Bode, M.; Dil, J. H.; Blügel, S.; Mavropoulos, P.; Sessi, P.
2018-02-01
The discovery of Weyl semimetals represents a significant advance in topological band theory. They paradigmatically enlarged the classification of topological materials to gapless systems while simultaneously providing experimental evidence for the long-sought Weyl fermions. Beyond fundamental relevance, their high mobility, strong magnetoresistance, and the possible existence of even more exotic effects, such as the chiral anomaly, make Weyl semimetals a promising platform to develop radically new technology. Fully exploiting their potential requires going beyond the mere identification of materials and calls for a detailed characterization of their functional response, which is severely complicated by the coexistence of surface- and bulk-derived topologically protected quasiparticles, i.e., Fermi arcs and Weyl points, respectively. Here, we focus on the type-II Weyl semimetal class in which we find a stoichiometry-dependent phase transition from a trivial to a nontrivial regime. By exploring the two extreme cases of the phase diagram, we demonstrate the existence of a universal response of both surface and bulk states to perturbations. We show that quasiparticle interference patterns originate from scattering events among surface arcs. Analysis reveals that topologically nontrivial contributions are strongly suppressed by spin texture. We also show that scattering at localized impurities can generate defect-induced quasiparticles sitting close to the Weyl point energy. These give rise to strong peaks in the local density of states, which lift the Weyl node, significantly altering the pristine low-energy spectrum. Remarkably, by comparing the WTe2 and the MoTe2 cases we found that scattering response and topological transition are not directly linked. Visualizing the existence of a universal microscopic response to scattering has important consequences for understanding the unusual transport properties of this class of materials. Overall, our observations provide
Losavio, Michael
2012-01-01
Information Crisis discusses the scope and types of information available online and teaches readers how to critically assess it and analyze potentially dangerous information, especially when teachers, editors, or other information gatekeepers are not available to assess the information for them. Chapters and topics include:. The Internet as an information tool. Critical analysis. Legal issues, traps, and tricks. Protecting personal safety and identity. Types of online information.
Rules for Phase Shifts of Quantum Oscillations in Topological Nodal-Line Semimetals
Li, Cequn; Wang, C. M.; Wan, Bo; Wan, Xiangang; Lu, Hai-Zhou; Xie, X. C.
2018-04-01
Nodal-line semimetals are topological semimetals in which band touchings form nodal lines or rings. Around a loop that encloses a nodal line, an electron can accumulate a nontrivial π Berry phase, so the phase shift in the Shubnikov-de Haas (SdH) oscillation may give a transport signature for the nodal-line semimetals. However, different experiments have reported contradictory phase shifts, in particular, in the WHM nodal-line semimetals (W =Zr /Hf , H =Si /Ge , M =S /Se /Te ). For a generic model of nodal-line semimetals, we present a systematic calculation for the SdH oscillation of resistivity under a magnetic field normal to the nodal-line plane. From the analytical result of the resistivity, we extract general rules to determine the phase shifts for arbitrary cases and apply them to ZrSiS and Cu3 PdN systems. Depending on the magnetic field directions, carrier types, and cross sections of the Fermi surface, the phase shift shows rich results, quite different from those for normal electrons and Weyl fermions. Our results may help explore transport signatures of topological nodal-line semimetals and can be generalized to other topological phases of matter.
Quantum phase transitions between a class of symmetry protected topological states
Energy Technology Data Exchange (ETDEWEB)
Tsui, Lokman; Jiang, Hong-Chen; Lu, Yuan-Ming; Lee, Dung-Hai
2015-07-01
The subject of this paper is the phase transition between symmetry protected topological states (SPTs). We consider spatial dimension d and symmetry group G so that the cohomology group, Hd+1(G,U(1)), contains at least one Z2n or Z factor. We show that the phase transition between the trivial SPT and the root states that generate the Z2n or Z groups can be induced on the boundary of a (d+1)-dimensional View the MathML source-symmetric SPT by a View the MathML source symmetry breaking field. Moreover we show these boundary phase transitions can be “transplanted” to d dimensions and realized in lattice models as a function of a tuning parameter. The price one pays is for the critical value of the tuning parameter there is an extra non-local (duality-like) symmetry. In the case where the phase transition is continuous, our theory predicts the presence of unusual (sometimes fractionalized) excitations corresponding to delocalized boundary excitations of the non-trivial SPT on one side of the transition. This theory also predicts other phase transition scenarios including first order transition and transition via an intermediate symmetry breaking phase.
Nonlocal optical response in topological phase transitions in the graphene family
Rodriguez-Lopez, Pablo; Kort-Kamp, Wilton J. M.; Dalvit, Diego A. R.; Woods, Lilia M.
2018-01-01
We investigate the electromagnetic response of staggered two-dimensional materials of the graphene family, including silicene, germanene, and stanene, as they are driven through various topological phase transitions using external fields. Utilizing Kubo formalism, we compute their optical conductivity tensor taking into account the frequency and wave vector of the electromagnetic excitations, and study its behavior over the full electronic phase diagram of the materials. In particular, we find that the resonant behavior of the nonlocal Hall conductivity is strongly affected by the various topological phases present in these materials. We also consider the plasmon excitations in the graphene family and find that nonlocality in the optical response can affect the plasmon dispersion spectra of the various phases. We find a regime of wave vectors for which the plasmon relations for phases with trivial topology are essentially indistinguishable, while those for phases with nontrivial topology are distinct and are redshifted as the corresponding Chern number increases. The expressions for the conductivity components are valid for the entire graphene family and can be readily used by others.
Phase Transitions in Geomorphology
Ortiz, C. P.; Jerolmack, D. J.
2015-12-01
Landscapes are patterns in a dynamic steady-state, due to competing processes that smooth or sharpen features over large distances and times. Geomorphic transport laws have been developed to model the mass-flux due to different processes, but are unreasonably effective at recovering the scaling relations of landscape features. Using a continuum approximation to compare experimental landscapes and the observed landscapes of the earth, one finds they share similar morphodynamics despite a breakdown of classical dynamical similarity between the two. We propose the origin of this effectiveness is a different kind of dynamic similarity in the statistics of initiation and cessation of motion of groups of grains, which is common to disordered systems of grains under external driving. We will show how the existing data of sediment transport points to common signatures with dynamical phase transitions between "mobile" and "immobile" phases in other disordered systems, particularly granular materials, colloids, and foams. Viewing landscape evolution from the lens of non-equilibrium statistical physics of disordered systems leads to predictions that the transition of bulk measurements such as particle flux is continuous from one phase to another, that the collective nature of the particle dynamics leads to very slow aging of bulk properties, and that the dynamics are history-dependent. Recent results from sediment transport experiments support these predictions, suggesting that existing geomorphic transport laws may need to be replaced by a new generation of stochastic models with ingredients based on the physics of disordered phase transitions. We discuss possible strategies for extracting the necessary information to develop these models from measurements of geomorphic transport noise by connecting particle-scale collective dynamics and space-time fluctuations over landscape features.
Photoinduced Topological Phase Transitions in Topological Magnon Insulators.
Owerre, S A
2018-03-13
Topological magnon insulators are the bosonic analogs of electronic topological insulators. They are manifested in magnetic materials with topologically nontrivial magnon bands as realized experimentally in a quasi-two-dimensional (quasi-2D) kagomé ferromagnet Cu(1-3, bdc), and they also possess protected magnon edge modes. These topological magnetic materials can transport heat as well as spin currents, hence they can be useful for spintronic applications. Moreover, as magnons are charge-neutral spin-1 bosonic quasiparticles with a magnetic dipole moment, topological magnon materials can also interact with electromagnetic fields through the Aharonov-Casher effect. In this report, we study photoinduced topological phase transitions in intrinsic topological magnon insulators in the kagomé ferromagnets. Using magnonic Floquet-Bloch theory, we show that by varying the light intensity, periodically driven intrinsic topological magnetic materials can be manipulated into different topological phases with different sign of the Berry curvatures and the thermal Hall conductivity. We further show that, under certain conditions, periodically driven gapped topological magnon insulators can also be tuned to synthetic gapless topological magnon semimetals with Dirac-Weyl magnon cones. We envision that this work will pave the way for interesting new potential practical applications in topological magnetic materials.
Development of phase lock loop system for synchronisation of a ...
African Journals Online (AJOL)
Phase locked loop (PLL) is an important part of the control unit of the grid connected power converter. The method of zero crossing detection (ZCD) does not produce accurate phase information when grid is non-ideal. In this work, a synchronous reference frame (SRF) PLL method to obtain accurate phase information when ...
Phase contrast image synthesis
DEFF Research Database (Denmark)
Glückstad, J.
1996-01-01
A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase funct...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....
Binding by asynchrony: the neuronal phase code
Directory of Open Access Journals (Sweden)
Zoltan Nadasdy
2010-09-01
Full Text Available Neurons display continuous subthreshold oscillations and discrete action potentials. When action potentials are phase-locked to the subthreshold oscillation, we hypothesize they represent two types of information: the presence/absence of a sensory feature and the phase of subthreshold oscillation. If subthreshold oscillation phases are neuron-specific, then the sources of action potentials can be recovered based on the action potential times. If the spatial information about the stimulus is converted to action potential phases, then action potentials from multiple neurons can be combined into a single axon and the spatial configuration reconstructed elsewhere. For the reconstruction to be successful, we introduce two assumptions: that a subthreshold oscillation field has a constant phase gradient and that coincidences between action potentials and intracellular subthreshold oscillations are neuron-specific as defined by the "interference principle." Under these assumptions, a phase coding model enables information transfer between structures and reproduces experimental phenomenons such as phase precession, grid cell architecture, and phase modulation of cortical spikes. This article reviews a recently proposed neuronal algorithm for information encoding and decoding from the phase of action potentials (Nadasdy 2009. The focus is given to the principles common across different systems instead of emphasizing system specific differences.
Equations of State and Phase Diagrams of Ammonia
Glasser, Leslie
2009-01-01
We present equations of state relating the phases and a three-dimensional phase diagram for ammonia with its solid, liquid, and vapor phases, based on fitted authentic experimental data and including recent information on the high-pressure solid phases. This presentation follows similar articles on carbon dioxide and water published in this…
High pressure phase transformations revisited.
Levitas, Valery I
2018-04-25
theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.
High pressure phase transformations revisited
Levitas, Valery I.
2018-04-01
theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.
Advances in intelligent process-aware information systems concepts, methods, and technologies
Oberhauser, Roy; Reichert, Manfred
2017-01-01
This book provides a state-of-the-art perspective on intelligent process-aware information systems and presents chapters on specific facets and approaches applicable to such systems. Further, it highlights novel advances and developments in various aspects of intelligent process-aware information systems and business process management systems. Intelligence capabilities are increasingly being integrated into or created in many of today’s software products and services. Process-aware information systems provide critical computing infrastructure to support the various processes involved in the creation and delivery of business products and services. Yet the integration of intelligence capabilities into process-aware information systems is a non-trivial yet necessary evolution of these complex systems. The book’s individual chapters address adaptive process management, case management processes, autonomically-capable processes, process-oriented information logistics, process recommendations, reasoning over ...
2012-03-01
This report introduces the design and implementation of a Web-based bridge information visual analytics system. This : project integrates Internet, multiple databases, remote sensing, and other visualization technologies. The result : combines a GIS ...
Saeidi, Parviz; Nourbakhsh, Zahra
2018-04-01
Topological phase of Gd1-xYxAuPb (x = 0, 0.25, 0.5, 0.75, 1) alloys have been studied utilizing density function theory by WIEN2k code. The generalized gradient approximation (GGA), generalized gradient approximation plus Hubbard parameter (GGA + U), Modified Becke and Johnson (MBJ) and GGA Engel-vosko in the presence of spin orbit coupling have been used to investigate the topological band structure of Gd1-xYxAuPb alloys at zero pressure. The topological phase and band order of these alloys within GGA and GGA + U approaches under hydrostatic pressure are also investigated. We find that under hydrostatic pressure in some percentages of Gd1-xYxAuPb (x = 0, 0.25, 0.5, 0.75, 1) alloys in both GGA and GGA + U approaches, the trivial topological phase is converted into nontrivial topological phase. In addition, the band inversion strength versus lattice constant of these alloys is studied. Moreover, the schematic plan is represented in order to show the trivial and nontrivial topological phase of Gd1-xYxAuPb (x = 0, 0.25, 0.5, 0.75, 1) alloys in both GGA and GGA + U approaches.
Energy Technology Data Exchange (ETDEWEB)
R. Wigeland; T. Taiwo; M. Todosow; W. Halsey; J. Gehin
2010-09-01
The Options Study has been conducted for the purpose of evaluating the potential of alternative integrated nuclear fuel cycle options to favorably address the issues associated with a continuing or expanding use of nuclear power in the United States. The study produced information that can be used to inform decisions identifying potential directions for research and development on such fuel cycle options. An integrated nuclear fuel cycle option is defined in this study as including all aspects of the entire nuclear fuel cycle, from obtaining natural resources for fuel to the ultimate disposal of used nuclear fuel (UNF) or radioactive wastes. Issues such as nuclear waste management, especially the increasing inventory of used nuclear fuel, the current uncertainty about used fuel disposal, and the risk of nuclear weapons proliferation have contributed to the reluctance to expand the use of nuclear power, even though it is recognized that nuclear power is a safe and reliable method of producing electricity. In this Options Study, current, evolutionary, and revolutionary nuclear energy options were all considered, including the use of uranium and thorium, and both once-through and recycle approaches. Available information has been collected and reviewed in order to evaluate the ability of an option to clearly address the challenges associated with the current implementation and potential expansion of commercial nuclear power in the United States. This Options Study is a comprehensive consideration and review of fuel cycle and technology options, including those for disposal, and is not constrained by any limitations that may be imposed by economics, technical maturity, past policy, or speculated future conditions. This Phase II report is intended to be used in conjunction with the Phase I report, and much information in that report is not repeated here, although some information has been updated to reflect recent developments. The focus in this Options Study was to
SGA Phase 2 Reach Segment Breaks
Vermont Center for Geographic Information — The stream geomorphic assessment (SGA) is a physical assessment competed by geomorphologists to determine the condition and sensitivity of a stream. The SGA Phase 2...
On the effect of the lattice asymmetry parameter on the phase structure of SU(N) pure gauge theories
International Nuclear Information System (INIS)
Averchenkova, L.A.; Petrov, K.V.; Petrov, V.K.; Zinovjev, G.M.
1998-01-01
The role of the lattice asymmetry parameter ξ in the phase structure description of the SU(2) and SU(3) gluodynamics at finite temperature has been studied analytically in the SU(N)∼Z(N) approach. The properties of thermodynamic quantities have been investigated near the physical border. The effective action which includes the first non-trivial order from the space-like part allows estimates to be made of the phase structure not only close to the physical border but in the whole area of couplings. We find that thermodynamic quantities depend on ξ and this dependence may be strong enough, up to discontinuity over this parameter for some of them. The Hamiltonian formulation of the SU(2) gauge theory on the asymmetric lattice is presented. (orig.)
Drift flux model as approximation of two fluid model for two phase dispersed and slug flow in tube
Energy Technology Data Exchange (ETDEWEB)
Nigmatulin, R.I.
1995-09-01
The analysis of one-dimensional schematizing for non-steady two-phase dispersed and slug flow in tube is presented. Quasi-static approximation, when inertia forces because of the accelerations of the phases may be neglected, is considered. Gas-liquid bubbly and slug vertical upward flows are analyzed. Non-trivial theoretical equations for slip velocity for these flows are derived. Juxtaposition of the derived equations for slip velocity with the famous Zuber-Findlay correlation as cross correlation coefficients is criticized. The generalization of non-steady drift flux Wallis theory taking into account influence of wall friction on the bubbly or slug flows for kinematical waves is considered.
Drift flux model as approximation of two fluid model for two phase dispersed and slug flow in tube
International Nuclear Information System (INIS)
Nigmatulin, R.I.
1995-01-01
The analysis of one-dimensional schematizing for non-steady two-phase dispersed and slug flow in tube is presented. Quasi-static approximation, when inertia forces because of the accelerations of the phases may be neglected, is considered. Gas-liquid bubbly and slug vertical upward flows are analyzed. Non-trivial theoretical equations for slip velocity for these flows are derived. Juxtaposition of the derived equations for slip velocity with the famous Zuber-Findlay correlation as cross correlation coefficients is criticized. The generalization of non-steady drift flux Wallis theory taking into account influence of wall friction on the bubbly or slug flows for kinematical waves is considered
International Nuclear Information System (INIS)
Brottes, Francois
2011-01-01
The first part of this report describes the progress made on local dialogue and information within the frame of the setting up of relay antennas. It describes the implemented method with a selection of nine local communities, the main results of the dialogue (establishment of an information file, development of a tool set for the pilot communities, and operation, steering and assessment of experimentations). The second part describes the progress made on the exposure of population to electromagnetic waves emitted by mobile phone relay antennas (context, method, exposure status, simulation of the decreasing of relay antenna power, site experimentations). The third part proposes a set of recommendations related to local dialogue and information and to exposure
Brignole, Esteban Alberto
2013-01-01
Traditionally, the teaching of phase equilibria emphasizes the relationships between the thermodynamic variables of each phase in equilibrium rather than its engineering applications. This book changes the focus from the use of thermodynamics relationships to compute phase equilibria to the design and control of the phase conditions that a process needs. Phase Equilibrium Engineering presents a systematic study and application of phase equilibrium tools to the development of chemical processes. The thermodynamic modeling of mixtures for process development, synthesis, simulation, design and
International Nuclear Information System (INIS)
Sikka, S.K.; Vohra, Y.K.; Chidambaram, R.
1982-01-01
The subject is reviewed under the headings: introduction; occurrence and some systematics of omega phase; crystallography; physical properties; kinetics of formation, synthesis and metastability of omega phase; electronic structure of omega phase; electronic basis for omega phase stability; omega phase formation under combined thermal and pressure treatment in alloys; transformation mechanisms and models for diffuse omega phase; conclusion. The following elements of nuclear interest (or their alloys) are included: Zr, Hf, Nb, V, Mo. (U.K.)
Assessment of autonomous phase unwrapping of isochromatic ...
Indian Academy of Sciences (India)
An excellent summary of phase unwrapping techniques applied to ... to fully exploit the advantage of these new developments, in this paper, ..... Madhu K R, Ramesh K 2007 New boundary information encoding and auto ... Ramesh K, Mangal S K 1999 Phase-shifting calculations in 2-D photoelasticity: revisited. J. Aero-.
The topological Anderson insulator phase in the Kane-Mele model
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.
Construction of the Lyapunov Spectrum in a Chaotic System Displaying Phase Synchronization
Energy Technology Data Exchange (ETDEWEB)
Carlo, Leonardo De, E-mail: neoleodeo@gmail.com [Gran Sasso Science Institute (GSSI) (Italy); Gentile, Guido, E-mail: gentile@mat.uniroma3.it; Giuliani, Alessandro, E-mail: giuliani@mat.uniroma3.it [Università degli Studi Roma Tre, Dipartimento di Matematica e Fisica (Italy)
2016-06-15
We consider a three-dimensional chaotic system consisting of the suspension of Arnold’s cat map coupled with a clock via a weak dissipative interaction. We show that the coupled system displays a synchronization phenomenon, in the sense that the relative phase between the suspension flow and the clock locks to a special value, thus making the motion fall onto a lower dimensional attractor. More specifically, we construct the attractive invariant manifold, of dimension smaller than three, using a convergent perturbative expansion. Moreover, we compute via convergent series the Lyapunov exponents, including notably the central one. The result generalizes a previous construction of the attractive invariant manifold in a similar but simpler model. The main novelty of the current construction relies in the computation of the Lyapunov spectrum, which consists of non-trivial analytic exponents. Some conjectures about a possible smoothening transition of the attractor as the coupling is increased are also discussed.
Effects of the phase periodicity on the quantum dynamics of a resistively shunted Josephson junction
International Nuclear Information System (INIS)
Zwerger, W.; Dorsey, A.T.; Fisher, M.P.A.
1986-01-01
A phenomenological model is introduced for the dissipative quantum dynamics of the phase phi across a current-biased Josephson junction. The model is invariant under phi→phi+2π. This enables us to restrict phi to the interval 0 to 2π, equating phi+2π with phi, and study the role played by the resulting nontrivial topology. Using Feynman's influence functional theory it is shown that the dissipation suppresses interference between paths with different winding numbers. For Ohmic dissipation this interference is completely destroyed, and phi can effectively be treated as an extended coordinate. This justifies the use of the usual washboard potential description of a current-biased junction even in the quantum case, provided an Ohmic dissipation mechanism is present
G2 holonomy, mirror symmetry and phases of N = 1 SYM
International Nuclear Information System (INIS)
Hosomichi, Kazuo; Page, David C.
2005-01-01
We study the phase structure of four-dimensional N = 1 super Yang-Mills theories realized on D6-branes wrapping the RP 3 of a Z 2 orbifold of the deformed conifold. The non-trivial fundamental group of RP 3 allows for the gauge group to be broken to various product groups by Z 2 Wilson lines. We study the classical moduli space of theories in various pictures related by dualities including an M-theory lift. The quantum moduli space is analyzed in a dual IIB theory, where a complex curve contained in the target space plays a key role. We find that the quantum moduli space is made up of several branches, characterized by the presence or absence of a low energy U(1) gauge symmetry, which are connected at points of monopole condensation. The resulting picture of the quantum moduli space shows how the various gauge theories with different product gauge groups are connected to one another
Dean, David S.; Majumdar, Satya N.
2002-08-01
We study a fragmentation problem where an initial object of size x is broken into m random pieces provided x > x0 where x0 is an atomic cut-off. Subsequently, the fragmentation process continues for each of those daughter pieces whose sizes are bigger than x0. The process stops when all the fragments have sizes smaller than x0. We show that the fluctuation of the total number of splitting events, characterized by the variance, generically undergoes a nontrivial phase transition as one tunes the branching number m through a critical value m = mc. For m mc they are anomalously large and non-Gaussian. We apply this general result to analyse two different search algorithms in computer science.
Nonequilibrium Physics and Phase-Field Modeling of Multiphase Flow in Porous Media
Energy Technology Data Exchange (ETDEWEB)
Juanes, Ruben [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
2016-09-01
The overarching goal of this project was to develop a new continuum theory of multiphase flow in porous media. The theory follows a phase-field modeling approach, and therefore has a sound thermodynamical basis. It is a phenomenological theory in the sense that its formulation is driven by macroscopic phenomena, such as viscous instabilities during multifluid displacement. The research agenda was organized around a set of hypothesis on hitherto unexplained behavior of multiphase flow. All these hypothesis are nontrivial, and testable. Indeed, a central aspect of the project was testing each hypothesis by means of carefully-designed laboratory experiments, therefore probing the validity of the proposed theory. The proposed research places an emphasis on the fundamentals of flow physics, but is motivated by important energy-driven applications in earth sciences, as well as microfluidic technology.
Imaginary geometric phases of quantum trajectories in high-order terahertz sideband generation
Yang, Fan; Liu, Ren-Bao
2014-03-01
Quantum evolution of particles under strong fields can be described by a small number of quantum trajectories that satisfy the stationary phase condition in the Dirac-Feynmann path integral. The quantum trajectories are the key concept to understand the high-order terahertz siedeband generation (HSG) in semiconductors. Due to the nontrivial ``vacuum'' states of band materials, the quantum trajectories of optically excited electron-hole pairs in semiconductors can accumulate geometric phases under the driving of an elliptically polarized THz field. We find that the geometric phase of the stationary trajectory is generally complex with both real and imaginary parts. In monolayer MoS2, the imaginary parts of the geometric phase leads to a changing of the polarization ellipticity of the sideband. We further show that the imaginary part originates from the quantum interference of many trajectories with different phases. Thus the observation of the polarization ellipticity of the sideband shall be a good indication of the quantum nature of the stationary trajectory. This work is supported by Hong Kong RGC/GRF 401512 and the CUHK Focused Investments Scheme.
Sato, Katsuhiko; Shima, Shin-ichiro
2015-10-01
We investigate a phase model that includes both locally attractive and globally repulsive coupling in one dimension. This model exhibits nontrivial spatiotemporal patterns that have not been observed in systems that contain only local or global coupling. Depending on the relative strengths of the local and global coupling and on the form of global coupling, the system can show a spatially uniform state (in-phase synchronization), a monotonically increasing state (traveling wave), and three types of oscillations of relative phase difference. One of the oscillations of relative phase difference has the characteristic of being locally unstable but globally attractive. That is, any small perturbation to the periodic orbit in phase space destroys its periodic motion, but after a long time the system returns to the original periodic orbit. This behavior is closely related to the emergence of saddle two-cluster states for global coupling only, which are connected to each other by attractive heteroclinic orbits. The mechanism of occurrence of this type of oscillation is discussed.
Chiral and color-superconducting phase transitions with vector interaction in a simple model
International Nuclear Information System (INIS)
Kitazawa, Masakiyo; Koide, Tomoi; Kunihiro, Teiji; Nemoto, Yukio
2002-01-01
We investigate effects of the vector interaction on chiral and color superconducting (CSC) phase transitions at finite density and temperature in a simple Nambu-Jona-Lasinio model. It is shown that the repulsive density-density interaction coming from the vector term, which is present in the effective chiral models but has been omitted, enhances the competition between the chiral symmetry breaking (χSB) and CSC phase transition, and thereby makes the thermodynamic potential have a shallow minimum over a wide range of values of the correlated chiral and CSC order parameters. We find that when the vector coupling is increased, the first order transition between the χSB and CSC phases becomes weaker, and the coexisting phase in which both the chiral and color-gauge symmetry are dynamically broken comes to exist over a wider range of the density and temperature. We also show that there can exist two endpoints, which are tricritical points in the chiral limit, along the critical line of the first order transition in some range of values of the vector coupling. Although our analysis is based on a simple model, the nontrivial interplay between the χSB and CSC phases induced by the vector interaction is expected to be a universal phenomenon and might give a clue to understanding results obtained with two-color QCD on the lattice. (author)
Extremal rotating black holes in the near-horizon limit: Phase space and symmetry algebra
Directory of Open Access Journals (Sweden)
G. Compère
2015-10-01
Full Text Available We construct the NHEG phase space, the classical phase space of Near-Horizon Extremal Geometries with fixed angular momenta and entropy, and with the largest symmetry algebra. We focus on vacuum solutions to d dimensional Einstein gravity. Each element in the phase space is a geometry with SL(2,R×U(1d−3 isometries which has vanishing SL(2,R and constant U(1 charges. We construct an on-shell vanishing symplectic structure, which leads to an infinite set of symplectic symmetries. In four spacetime dimensions, the phase space is unique and the symmetry algebra consists of the familiar Virasoro algebra, while in d>4 dimensions the symmetry algebra, the NHEG algebra, contains infinitely many Virasoro subalgebras. The nontrivial central term of the algebra is proportional to the black hole entropy. The conserved charges are given by the Fourier decomposition of a Liouville-type stress-tensor which depends upon a single periodic function of d−3 angular variables associated with the U(1 isometries. This phase space and in particular its symmetries can serve as a basis for a semiclassical description of extremal rotating black hole microstates.
Directory of Open Access Journals (Sweden)
Luiz Fernando de Barros Campos
Full Text Available Based on Erving Goffman's work, the article aims to discuss a definition of information centered on the type conveyed by individuals in a multimodal way, encompassing language and body in situations of co-presence, where face-to-face interaction occurs, and influencing inter-subjective formation of the self. Six types of information are highlighted: material information, expressive information, ritualized information, meta-information, strategic information, and information displays. It is argued that the construction of this empirical object tends to dissolve the tension among material, cognitive and pragmatic aspects, constituting an example of the necessary integration among them. Some vulnerable characteristics of the theory are critically mentioned and it is suggested that the concept of information displays could provide a platform to approach the question of the interaction order in its relations with the institutional and social orders, and consequently, to reassess the scope of the notion of social information analyzed.
Power inverter implementing phase skipping control
Somani, Utsav; Amirahmadi, Ahmadreza; Jourdan, Charles; Batarseh, Issa
2016-10-18
A power inverter includes a DC/AC inverter having first, second and third phase circuitry coupled to receive power from a power source. A controller is coupled to a driver for each of the first, second and third phase circuitry (control input drivers). The controller includes an associated memory storing a phase skipping control algorithm, wherein the controller is coupled to receive updating information including a power level generated by the power source. The drivers are coupled to control inputs of the first, second and third phase circuitry, where the drivers are configured for receiving phase skipping control signals from the controller and outputting mode selection signals configured to dynamically select an operating mode for the DC/AC inverter from a Normal Control operation and a Phase Skipping Control operation which have different power injection patterns through the first, second and third phase circuitry depending upon the power level.
Spline based iterative phase retrieval algorithm for X-ray differential phase contrast radiography.
Nilchian, Masih; Wang, Zhentian; Thuering, Thomas; Unser, Michael; Stampanoni, Marco
2015-04-20
Differential phase contrast imaging using grating interferometer is a promising alternative to conventional X-ray radiographic methods. It provides the absorption, differential phase and scattering information of the underlying sample simultaneously. Phase retrieval from the differential phase signal is an essential problem for quantitative analysis in medical imaging. In this paper, we formalize the phase retrieval as a regularized inverse problem, and propose a novel discretization scheme for the derivative operator based on B-spline calculus. The inverse problem is then solved by a constrained regularized weighted-norm algorithm (CRWN) which adopts the properties of B-spline and ensures a fast implementation. The method is evaluated with a tomographic dataset and differential phase contrast mammography data. We demonstrate that the proposed method is able to produce phase image with enhanced and higher soft tissue contrast compared to conventional absorption-based approach, which can potentially provide useful information to mammographic investigations.
On the role of spatial phase and phase correlation in vision, illusion, and cognition.
Gladilin, Evgeny; Eils, Roland
2015-01-01
Numerous findings indicate that spatial phase bears an important cognitive information. Distortion of phase affects topology of edge structures and makes images unrecognizable. In turn, appropriately phase-structured patterns give rise to various illusions of virtual image content and apparent motion. Despite a large body of phenomenological evidence not much is known yet about the role of phase information in neural mechanisms of visual perception and cognition. Here, we are concerned with analysis of the role of spatial phase in computational and biological vision, emergence of visual illusions and pattern recognition. We hypothesize that fundamental importance of phase information for invariant retrieval of structural image features and motion detection promoted development of phase-based mechanisms of neural image processing in course of evolution of biological vision. Using an extension of Fourier phase correlation technique, we show that the core functions of visual system such as motion detection and pattern recognition can be facilitated by the same basic mechanism. Our analysis suggests that emergence of visual illusions can be attributed to presence of coherently phase-shifted repetitive patterns as well as the effects of acuity compensation by saccadic eye movements. We speculate that biological vision relies on perceptual mechanisms effectively similar to phase correlation, and predict neural features of visual pattern (dis)similarity that can be used for experimental validation of our hypothesis of "cognition by phase correlation."
On the role of spatial phase and phase correlation in vision, illusion and cognition
Directory of Open Access Journals (Sweden)
Evgeny eGladilin
2015-04-01
Full Text Available Numerous findings indicate that spatial phase bears an important cognitive information. Distortion of phase affects topology of edge structures and makes images unrecognizable. In turn, appropriately phase-structured patterns give rise to various illusions of virtual image content and apparent motion. Despite a large body of phenomenological evidence not much is known yet about the role of phase information in neural mechanisms of visual perception and cognition. Here, we are concerned with analysis of the role of spatial phase in computational and biological vision, emergence of visual illusions and pattern recognition. We hypothesize that fundamental importance of phase information for invariant retrieval of structural image features and motion detection promoted development of phase-based mechanisms of neural image processing in course of evolution of biological vision. Using an extension of Fourier phase correlation technique, we show that the core functions of visual system such as motion detection and pattern recognition can be facilitated by the same basic mechanism. Our analysis suggests that emergence of visual illusions can be attributed to presence of coherently phase-shifted repetitive patterns as well as the effects of acuity compensation by saccadic eye movements. We speculate that biological vision relies on perceptual mechanisms effectively similar to phase correlation, and predict neural features of visual pattern (dissimilarity that can be used for experimental validation of our hypothesis of 'cognition by phase correlation'.
2006-01-01
This month has seen the launch of the second two-year phase of the Enabling Grids for E-sciencE project (EGEE-II), with a transition meeting for the partners held at CERN on 12-13 April. Co-funded by the European Commission and coordinated by CERN, the EGEE project is providing an international Grid computing infrastructure - now numbering some 200 sites and 20 000 CPUs in 39 countries - to support the scientific community worldwide. 'We are all very happy about the smooth start of the second phase of EGEE,' said Project Director Bob Jones. 'The project builds on the successes of its first two years and we are now focussing on the stability of the deployed infrastructure. Growing beyond our pilot application areas of HEP and biomedicine, we now see increasing use by researchers from other fields. Recently we've added finance and fusion to the list of disciplines we support, and we are always looking for new users.' More information on EGEE can be found at www.eu-egee.org.
Schleich, Wolfgang P.
2001-04-01
Quantum Optics in Phase Space provides a concise introduction to the rapidly moving field of quantum optics from the point of view of phase space. Modern in style and didactically skillful, Quantum Optics in Phase Space prepares students for their own research by presenting detailed derivations, many illustrations and a large set of workable problems at the end of each chapter. Often, the theoretical treatments are accompanied by the corresponding experiments. An exhaustive list of references provides a guide to the literature. Quantum Optics in Phase Space also serves advanced researchers as a comprehensive reference book. Starting with an extensive review of the experiments that define quantum optics and a brief summary of the foundations of quantum mechanics the author Wolfgang P. Schleich illustrates the properties of quantum states with the help of the Wigner phase space distribution function. His description of waves ala WKB connects semi-classical phase space with the Berry phase. These semi-classical techniques provide deeper insight into the timely topics of wave packet dynamics, fractional revivals and the Talbot effect. Whereas the first half of the book deals with mechanical oscillators such as ions in a trap or atoms in a standing wave the second half addresses problems where the quantization of the radiation field is of importance. Such topics extensively discussed include optical interferometry, the atom-field interaction, quantum state preparation and measurement, entanglement, decoherence, the one-atom maser and atom optics in quantized light fields. Quantum Optics in Phase Space presents the subject of quantum optics as transparently as possible. Giving wide-ranging references, it enables students to study and solve problems with modern scientific literature. The result is a remarkably concise yet comprehensive and accessible text- and reference book - an inspiring source of information and insight for students, teachers and researchers alike.
International Nuclear Information System (INIS)
Koizumi, Hiroyasu
2013-01-01
When Schrödinger solved the Schrödinger equation for the hydrogen atom, he assumed the single-valuedness of the electronic wave function. Thereafter, this assumption has been one of the fundamental postulates of quantum mechanics. When wave functions are multi-component, however, the imposing of the single-valued condition may become nontrivial. The spin-degree-of-freedom of electron makes electronic wave functions two-component. When spin-vortices are created by the conduction electrons and they move in the self-consistent field with the spin-vortices, the twisting of the spin basis occurs; then, the imposing of the single-valued condition becomes nontrivial, and a vector potential is induced. As a consequence, the effective vector potential becomes the sum of the vector potential from the induced one and that originates from the electric current. This effective vector potential is gauge invariant and the persistent current is generated by it. In the present work, we argue that if interactions that are omitted in the BCS reduced Hamiltonian are included, spin-vortices may be generated upon the application of a magnetic field. Then, the vector potential is induced and provides with the phase variable, θ, of the electron pair amplitude. The appearance of the spin-vortex provides with a new origin of θ; it originates from the induced gauge potential. This origin is compatible with the superselection rule for charge in contrast to the currently-accepted origin.
Zhang, Qianfan
2012-03-27
Topological insulator is a new state of matter attracting tremendous interest due to its gapless linear dispersion and spin momentum locking topological states located near the surface. Heterostructures, which have traditionally been powerful in controlling the electronic properties of semiconductor devices, are interesting for topological insulators. Here, we studied the spatial distribution of the topological state in Sb 2Se 3-Bi 2Se 3 heterostructures by first-principle simulation and discovered that an exotic topological state exists. Surprisingly, the state migrates from the nontrivial Bi 2Se 3 into the trivial Sb 2Se 3 region and spreads across the entire Sb 2Se 3 slab, extending beyond the concept of "surface" state while preserving all of the topological surface state characteristics. This unusual topological state arises from the coupling between different materials and the modification of electronic structure near Fermi energy. Our study demonstrates that heterostructures can open up opportunities for controlling the real-space distribution of the topological state and inducing quantum phase transitions between topologically trivial and nontrivial states. © 2012 American Chemical Society.
Marchionini, Gary
2010-01-01
Information is essential to all human activity, and information in electronic form both amplifies and augments human information interactions. This lecture surveys some of the different classical meanings of information, focuses on the ways that electronic technologies are affecting how we think about these senses of information, and introduces an emerging sense of information that has implications for how we work, play, and interact with others. The evolutions of computers and electronic networks and people's uses and adaptations of these tools manifesting a dynamic space called cyberspace. O
Directory of Open Access Journals (Sweden)
Nadi Helena Presser
2016-04-01
Full Text Available This article reflects on the ways of appropriation in organizations. The notion of Information Myopia is characterized by the lack of knowledge about the available informational capabilities in organizations, revealing a narrow view of the information environment. This analysis has focused on the process for renewing the software licenses contracts of a large multinational group, in order to manage its organizational assets in information technology. The collected, explained and justified information allowed to elaborate an action proposal, which enabled the creation of new organizational knowledge. In its theoretical dimension, the value of information was materialized by its use, in a collective process of organizational learning.
DEFF Research Database (Denmark)
Skouvig, Laura
2017-01-01
The purpose of this article is to suggest a genealogy of the concept of information beyond the 20th century. The article discusses how the concept of information culture might provide a way of formulating such a genealogic strategy. The article approaches this purpose by providing a general...... narrative of premodern information cultures, examining works on early-modern scholars and 18th century savants and discussion of what seems to be a Foucauldian rupture in the conceptualization of information in 19th century England. The findings of the article are situated in the thinking that a genealogy...... of information would reveal that information had specific purposes in specific settings....
Dare we rethink informed consent?
African Journals Online (AJOL)
2017-06-26
Jun 26, 2017 ... the current phase of human societal development as fundamentally complex ... and informed decisions. This is ... contained or containable, packaged or like data on a memory stick/ ... Our intention is finally to promote patient autonomy ... verb 'to inform' (to shape, like a sculptor) illustrates the multifaceted,.
DEFF Research Database (Denmark)
Glückstad, Jesper; Palima, Darwin
Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast...
African Journals Online (AJOL)
USER
Use of Online Information Sources in Federal University Medical Libraries in North West Geo-Political Zone of Nigeria. By ... on the quality of information services provided to clients. .... North West Zone need to identify the importance of.
Directory of Open Access Journals (Sweden)
Wolfgang G. Stock
2015-10-01
Full Text Available Contemporary and future cities are often labeled as "smart cities," "ubiquitous cities," "knowledge cities" and "creative cities." Informational urbanism includes all aspects of information and knowledge with regard to urban regions. "Informational city" is an umbrella term uniting the divergent trends of information-related city research. Informational urbanism is an interdisciplinary endeavor incorporating on the one side computer science and information science and on the other side urbanism, architecture, (city economics, and (city sociology. In our research project on informational cities, we visited more than 40 metropolises and smaller towns all over the world. In this paper, we sketch the theoretical background on a journey from Max Weber to the Internet of Things, introduce our research methods, and describe main results on characteristics of informational cities as prototypical cities of the emerging knowledge society.
... Here: Home → Copyright Information URL of this page: https://medlineplus.gov/copyright.html Copyright Information To use ... the Magazine and NIH MedlinePlus Salud The FAQs ( https://medlineplus.gov/faq/faq.html ) The same content ...
African Journals Online (AJOL)
ian
The paper also discusses some challenges faced in the teaching ... groups, language and cultural barriers and time and lack of computers. The paper ... administrative staff, researchers and librarians work with information. ...... The role of Information and Communication Technologies in Harnessing Information for women in.
Phase-Modulated Optical Communication Systems
Ho, Keang-Po
2005-01-01
Fiber-optic communication systems have revolutionized our telecommunication infrastructures – currently, almost all telephone land-line, cellular, and internet communications must travel via some form of optical fibers. In these transmission systems, neither the phase nor frequency of the optical signal carries information – only the intensity of the signal is used. To transmit more information in a single optical carrier, the phase of the optical carrier must be explored. As a result, there is renewed interest in phase-modulated optical communications, mainly in direct-detection DPSK signals for long-haul optical communication systems. When optical amplifiers are used to maintain certain signal level among the fiber link, the system is limited by amplifier noises and fiber nonlinearities. Phase-Modulated Optical Communication Systems surveys this newly popular area, covering the following topics: The transmitter and receiver for phase-modulated coherent lightwave systems Method for performance analysis o...
Agent review phase one report.
Energy Technology Data Exchange (ETDEWEB)
Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell
2009-12-01
This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.
Energy Technology Data Exchange (ETDEWEB)
Su, Fang [Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China, Institute of Theoretical Physics, Beijing (China); Huazhong Normal University, Institute of Particle Physics, Wuhan, Hubei (China); Wu, Yue-Liang; Zhuang, Ci [Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China, Institute of Theoretical Physics, Beijing (China); Yang, Yi-Bo [Chinese Academy of Sciences, State Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China, Institute of Theoretical Physics, Beijing (China); Chinese Academy of Sciences, Institute of High Energy Physics, Beijing (China)
2012-03-15
We provide a systematic study of charmless B{sub s}{yields}PP, PV, VV decays (P and V denote pseudoscalar and vector mesons, respectively) based on an approximate six-quark operator effective Hamiltonian from QCD. The calculation of the relevant hard-scattering kernels is carried out, the resulting transition form factors are consistent with the results of QCD sum-rule calculations. By taking into account important classes of power corrections involving ''chirally enhanced'' terms and the vertex corrections as well as weak annihilation contributions with non-trivial strong phase, we present predictions for the branching ratios and CP asymmetries of B{sub s} decays into PP, PV and VV final states, and also for the corresponding polarization observables in VV final states. It is found that the weak annihilation contributions with non-trivial strong phase have remarkable effects on the observables in the color-suppressed and penguin-dominated decay modes. In addition, we discuss the SU(3) flavor symmetry and show that the symmetry relations are generally respected. (orig.)
Absorbing phase transitions in deterministic fixed-energy sandpile models
Park, Su-Chan
2018-03-01
We investigate the origin of the difference, which was noticed by Fey et al. [Phys. Rev. Lett. 104, 145703 (2010), 10.1103/PhysRevLett.104.145703], between the steady state density of an Abelian sandpile model (ASM) and the transition point of its corresponding deterministic fixed-energy sandpile model (DFES). Being deterministic, the configuration space of a DFES can be divided into two disjoint classes such that every configuration in one class should evolve into one of absorbing states, whereas no configurations in the other class can reach an absorbing state. Since the two classes are separated in terms of toppling dynamics, the system can be made to exhibit an absorbing phase transition (APT) at various points that depend on the initial probability distribution of the configurations. Furthermore, we show that in general the transition point also depends on whether an infinite-size limit is taken before or after the infinite-time limit. To demonstrate, we numerically study the two-dimensional DFES with Bak-Tang-Wiesenfeld toppling rule (BTW-FES). We confirm that there are indeed many thresholds. Nonetheless, the critical phenomena at various transition points are found to be universal. We furthermore discuss a microscopic absorbing phase transition, or a so-called spreading dynamics, of the BTW-FES, to find that the phase transition in this setting is related to the dynamical isotropic percolation process rather than self-organized criticality. In particular, we argue that choosing recurrent configurations of the corresponding ASM as an initial configuration does not allow for a nontrivial APT in the DFES.
Using phase for radar scatterer classification
Moore, Linda J.; Rigling, Brian D.; Penno, Robert P.; Zelnio, Edmund G.
2017-04-01
Traditional synthetic aperture radar (SAR) systems tend to discard phase information of formed complex radar imagery prior to automatic target recognition (ATR). This practice has historically been driven by available hardware storage, processing capabilities, and data link capacity. Recent advances in high performance computing (HPC) have enabled extremely dense storage and processing solutions. Therefore, previous motives for discarding radar phase information in ATR applications have been mitigated. First, we characterize the value of phase in one-dimensional (1-D) radar range profiles with respect to the ability to correctly estimate target features, which are currently employed in ATR algorithms for target discrimination. These features correspond to physical characteristics of targets through radio frequency (RF) scattering phenomenology. Physics-based electromagnetic scattering models developed from the geometrical theory of diffraction are utilized for the information analysis presented here. Information is quantified by the error of target parameter estimates from noisy radar signals when phase is either retained or discarded. Operating conditions (OCs) of signal-tonoise ratio (SNR) and bandwidth are considered. Second, we investigate the value of phase in 1-D radar returns with respect to the ability to correctly classify canonical targets. Classification performance is evaluated via logistic regression for three targets (sphere, plate, tophat). Phase information is demonstrated to improve radar target classification rates, particularly at low SNRs and low bandwidths.
International Nuclear Information System (INIS)
2011-12-01
As previous works performed by the CODIRPA proposed the creation of Centres for public reception and information (CAIs) within the population protection area, and as local groups have been created in three districts (Vienne, Haut-Rhin, Drome) to work on the preparation of the implementation of such centres, this report proposes a synthesis of these previous works, examines the doctrine related to the support to victims of collective accidents by the ministry of interior and by the ministry of justice, and finally makes recommendations and proposals for the implementation of CAIs in a post-accidental situation
Olken, Benjamin A; Singhal, Monica
2011-10-01
Informal payments are a frequently overlooked source of local public finance in developing countries. We use microdata from ten countries to establish stylized facts on the magnitude, form, and distributional implications of this "informal taxation." Informal taxation is widespread, particularly in rural areas, with substantial in-kind labor payments. The wealthy pay more, but pay less in percentage terms, and informal taxes are more regressive than formal taxes. Failing to include informal taxation underestimates household tax burdens and revenue decentralization in developing countries. We discuss various explanations for and implications of these observed stylized facts.
Olken, Benjamin A.; Singhal, Monica
2011-01-01
Informal payments are a frequently overlooked source of local public finance in developing countries. We use microdata from ten countries to establish stylized facts on the magnitude, form, and distributional implications of this “informal taxation.” Informal taxation is widespread, particularly in rural areas, with substantial in-kind labor payments. The wealthy pay more, but pay less in percentage terms, and informal taxes are more regressive than formal taxes. Failing to include informal taxation underestimates household tax burdens and revenue decentralization in developing countries. We discuss various explanations for and implications of these observed stylized facts. PMID:22199993
The Cost of Enforcing Building Energy Codes: Phase 2
Energy Technology Data Exchange (ETDEWEB)
Williams, Alison [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Sarah K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Vine, Ed [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
2014-10-15
The purpose of this study is to present key findings regarding costs associated with enforcing building energy code compliance–primarily focusing on costs borne by local government. Building codes, if complied with, have the ability to save a significant amount of energy. However, energy code compliance rates have been significantly lower than 100%. Renewed interest in building energy codes has focused efforts on increasing compliance, particularly as a result of the 2009 American Recovery and Reinvestment Act (ARRA) requirement that in order for states to receive additional energy grants, they must have “a plan for the jurisdiction achieving compliance with the building energy code…in at least 90 percent of new and renovated residential and commercial building space” by 2017 (Public Law 111-5, Section 410(2)(C)). One study by the Institute for Market Transformation (IMT) estimated the costs associated with reaching 90% compliance to be $810 million, or $610 million in additional funding over existing expenditures, a non-trivial value. [Majersik & Stellberg 2010] In this context, Lawrence Berkeley National Laboratory (LBNL) conducted a study to better pinpoint the costs of enforcement through a two-phase process.
Quantum Walks on the Line with Phase Parameters
Villagra, Marcos; Nakanishi, Masaki; Yamashita, Shigeru; Nakashima, Yasuhiko
In this paper, a study on discrete-time coined quantum walks on the line is presented. Clear mathematical foundations are still lacking for this quantum walk model. As a step toward this objective, the following question is being addressed: Given a graph, what is the probability that a quantum walk arrives at a given vertex after some number of steps? This is a very natural question, and for random walks it can be answered by several different combinatorial arguments. For quantum walks this is a highly non-trivial task. Furthermore, this was only achieved before for one specific coin operator (Hadamard operator) for walks on the line. Even considering only walks on lines, generalizing these computations to a general SU(2) coin operator is a complex task. The main contribution is a closed-form formula for the amplitudes of the state of the walk (which includes the question above) for a general symmetric SU(2) operator for walks on the line. To this end, a coin operator with parameters that alters the phase of the state of the walk is defined. Then, closed-form solutions are computed by means of Fourier analysis and asymptotic approximation methods. We also present some basic properties of the walk which can be deducted using weak convergence theorems for quantum walks. In particular, the support of the induced probability distribution of the walk is calculated. Then, it is shown how changing the parameters in the coin operator affects the resulting probability distribution.
International Nuclear Information System (INIS)
Waldahl, R.
1995-01-01
The Chernobyl accident in 1986 uncovered serious information problems in many Western countries, and started a debate on crisis communication and information strategies in relation to radiation danger in society. The information problem focuses on four main perspectives. The first is related to information as a persuasion process in which an efficient strategy would influence both the public's knowledge of radiation danger, their attitude towards it and their behaviour. The second perspective calls attention to the importance of the different elements of the information process. How important are different characteristics of the information source; the message itself, and the receiver? The third perspective concentrates on different types of information. What is this issue all about, why is the situation as it is, and how should people behave to protect themselves? The fourth perspective points to the various phases of a crisis. The information needed is obviously not the same in the period before a crisis emerges when no one knows what is going to happen, in the warning period when one knows that something may happen, and during the crisis itself. (Author)
Floquet engineering of Haldane Chern insulators and chiral bosonic phase transitions
Plekhanov, Kirill; Roux, Guillaume; Le Hur, Karyn
2017-01-01
The realization of synthetic gauge fields has attracted a lot of attention recently in relation to periodically driven systems and the Floquet theory. In ultracold atom systems in optical lattices and photonic networks, this allows one to simulate exotic phases of matter such as quantum Hall phases, anomalous quantum Hall phases, and analogs of topological insulators. In this paper, we apply the Floquet theory to engineer anisotropic Haldane models on the honeycomb lattice and two-leg ladder systems. We show that these anisotropic Haldane models still possess a topologically nontrivial band structure associated with chiral edge modes. Focusing on (interacting) boson systems in s -wave bands of the lattice, we show how to engineer through the Floquet theory, a quantum phase transition (QPT) between a uniform superfluid and a Bose-Einstein condensate analog of Fulde-Ferrell-Larkin-Ovchinnikov states, where bosons condense at nonzero wave vectors. We perform a Ginzburg-Landau analysis of the QPT on the graphene lattice, and compute observables such as chiral currents and the momentum distribution. The results are supported by exact diagonalization calculations and compared with those of the isotropic situation. The validity of high-frequency expansion in the Floquet theory is also tested using time-dependent simulations for various parameters of the model. Last, we show that the anisotropic choice for the effective vector potential allows a bosonization approach in equivalent ladder (strip) geometries.
International Nuclear Information System (INIS)
Ramos, Rudnei O.
2006-01-01
Topological excitations are believed to play an important role in different areas of physics. For example, cases of topical interest are the study of contributions of nonhomogeneous field configurations, in particular those of topological nature (like kinks, vortices and monopoles) in phase transitions associated to spontaneous symmetry breaking, the use of topological excitations in dual models of QCD to understand properties of its vacuum and confinement through the condensation of magnetic monopoles and vortices and also the relevance of these nonhomogeneous type of configurations in cosmology, again associated to possible phase transitions that are expected to have happened in the early universe. Here we show a derivation of a model dual to the scalar Abelian Higgs model where its topological excitations, namely vortex-strings, become manifest and can be treated in a quantum field theory way. The contribution of these nontrivial vacuum excitations in the phase transition for the scalar Abelian Higgs model in a thermal background is then studied and the results interpreted from the computation of the partition function taking into account the vortice-strings in the functional integration. This is made possible from the derived dual action. The relevance of the obtained results in cosmology, the analogy with phase transitions in superconductors, the relevance also for the study of confinement and other extensions of our calculations are briefly discussed here. (author)
Phase space and jet definitions in soft-collinear effective theory
International Nuclear Information System (INIS)
Cheung, William Man-Yin; Luke, Michael; Zuberi, Saba
2009-01-01
We discuss consistent power counting for integrating soft and collinear degrees of freedom over arbitrary regions of phase space in the soft-collinear effective theory, and illustrate our results at one-loop with several jet algorithms: JADE, Sterman-Weinberg and k perpendicular . Consistently applying soft-collinear effective theory power counting in phase space, along with nontrivial zero-bin subtractions, prevents double counting of final states. The resulting phase space integrals over soft and collinear regions are individually ultraviolet divergent, but the phase space ultraviolet divergences cancel in the sum. Whether the soft and collinear contributions are individually infrared safe depends on the jet definition. We show that while this is true at one-loop for JADE and Sterman-Weinberg, the k perpendicular algorithm does not factorize into individually infrared safe soft and collinear pieces in dimensional regularization. We point out that this statement depends on the ultraviolet regulator, and that in a cutoff scheme the soft functions are infrared safe.
Phase transition in a quark-gluon plasma and hydrodynamic theory
International Nuclear Information System (INIS)
Chernavskaya, O.D.; Chernavskij, D.S.
1988-01-01
A wide range of problem concerning the phase transition of a quark-gluon plasma to the hadron matter is considered in connection with the hardronization problem within the frame of the hydrodynamical theory of ultra-relativistic collisions. A short review of the present hadron models and possible mechanisms of thermalization is given. The character of the phase transition within the bag model is analysed, effects of the surface interaction result in a nontrivial character of the phase transition: the metastable states of matter become possible. The review of the possible scenaria of hadronization of the cooling hydrodynamical matter is given, the choice between them is determined by a kinetic analysis. The systems with the energy density near the critical point (∼ 4 GeV/Fm 3 ) are shown to be hadronized by the mechanism based on a strong plasma supercooling (with a considerable transverse momentum increase). The traditional hadronization mechanism (mixed phase) is preferable for more hot systems. Theoretical estimations are compared with the JACEE (cosmic rays) data
Parallel imaging with phase scrambling.
Zaitsev, Maxim; Schultz, Gerrit; Hennig, Juergen; Gruetter, Rolf; Gallichan, Daniel
2015-04-01
Most existing methods for accelerated parallel imaging in MRI require additional data, which are used to derive information about the sensitivity profile of each radiofrequency (RF) channel. In this work, a method is presented to avoid the acquisition of separate coil calibration data for accelerated Cartesian trajectories. Quadratic phase is imparted to the image to spread the signals in k-space (aka phase scrambling). By rewriting the Fourier transform as a convolution operation, a window can be introduced to the convolved chirp function, allowing a low-resolution image to be reconstructed from phase-scrambled data without prominent aliasing. This image (for each RF channel) can be used to derive coil sensitivities to drive existing parallel imaging techniques. As a proof of concept, the quadratic phase was applied by introducing an offset to the x(2) - y(2) shim and the data were reconstructed using adapted versions of the image space-based sensitivity encoding and GeneRalized Autocalibrating Partially Parallel Acquisitions algorithms. The method is demonstrated in a phantom (1 × 2, 1 × 3, and 2 × 2 acceleration) and in vivo (2 × 2 acceleration) using a 3D gradient echo acquisition. Phase scrambling can be used to perform parallel imaging acceleration without acquisition of separate coil calibration data, demonstrated here for a 3D-Cartesian trajectory. Further research is required to prove the applicability to other 2D and 3D sampling schemes. © 2014 Wiley Periodicals, Inc.
Two-dimensional phase fraction charts
International Nuclear Information System (INIS)
Morral, J.E.
1984-01-01
A phase fraction chart is a graphical representation of the amount of each phase present in a system as a function of temperature, composition or other variable. Examples are phase fraction versus temperature charts used to characterize specific alloys and as a teaching tool in elementary texts, and Schaeffler diagrams used to predict the amount of ferrite in stainless steel welds. Isothermal-transformation diagrams (TTT diagrams) are examples that give phase (or microconstituent) amount versus temperature and time. The purpose of this communication is to discuss the properties of two-dimensional phase fraction charts in more general terms than have been reported before. It is shown that they can represent multi-component, multiphase equilibria in a way which is easier to read and which contains more information than the isotherms and isopleths of multi-component phase diagrams
Weak-light phase locking for LISA
International Nuclear Information System (INIS)
McNamara, Paul W
2005-01-01
The long armlengths of the LISA interferometer, and the finite aperture of the telescope, lead to an optical power attenuation of ∼10 -10 of the transmitted to received light. Simple reflection at the end of the arm is therefore not an optimum interferometric design. Instead, a local laser is offset phase locked to the weak incoming beam, transferring the phase information of the incoming to the outgoing light. This paper reports on an experiment to characterize a weak-light phase-locking scheme suitable for LISA in which a diode-pumped, Nd:YAG, non-planar ring oscillator (NPRO) is offset phase locked to a low-power (13 pW) frequency stabilized master NPRO. Preliminary results of the relative phase noise of the slave laser shows shot noise limited performance above 0.4 Hz. Excess noise is observed at lower frequencies, most probably due to thermal effects in the optical arrangement and phase-sensing electronics
The CEBAF fiber optic phase reference system
International Nuclear Information System (INIS)
Crawford, K.; Simrock, S.; Hovater, C.; Krycuk, A.
1995-01-01
The specified phase stability of the CEBAF RF distribution system is 2.9 degree rms per linac. Stability is achieved through the use of a temperature and pressure regulated coaxial drive line. Purpose of the fiber optic phase reference system is to monitor the relative phase at the beginning and ending of this drive line, between linacs, injector and separator to determine drift due to ambient temperature fluctuations. The system utilizes an Ortel 1310 nm single mode laser driving Sumitumo optical fiber to distribute a reference signal at 1497 MHz. Phase of this reference signal is compared to the 1427 MHz (LO) and the 70 MHz (IF) via a 360 degree phase detector. The detected information is then routed to the CEBAF control system for display with a specified resolution of ±0.2 degree over a 20 degree phase delta
Energy Technology Data Exchange (ETDEWEB)
O' Brien, Karen; Sygna, Linda; Naess, Lars Otto; Kingamkono, Robert; Hochobeb, Ben
2000-05-01
Since the mid-1980s, long-lead climate forecasts have been developed and used to predict the onset of El Nino events and their impact on climate variability. This report discusses user responses to seasonal climate forecasts in southern Africa, with an emphasis on small-scale farmers in Namibia and Tanzania. The study examines how farmers received and used the forecasts in the agricultural season of 1997/1998. It also summarises a workshop on user responses to seasonal forecasts in southern Africa. Comparison of case studies across south Africa revealed differences in forecast dissemination strategies and in the capacity to respond to extreme events. However, improving these strategies and the capacity to respond to the forecasts would yield net profit to agriculture in southern Africa. In anticipation of potential changes in the frequency or magnitude of extreme events associated with global climate change, there clearly is a need for improved seasonal forecasts and improved information dissemination.
Esina, Zoya; Miroshnikov, Aleksandr; Korchuganova, Margarita
2014-01-01
The PCEAS model was used to study the liquid-solid and liquid-vapor phase transitions at constant pressure in systems containing glycols and glycol ethers. This method is based on minimizing the excess Gibbs energy over the solvation parameter, which takes into account the processes of association of molecules in various phases. To compute the diagrams, the data on enthalpy and phase transition temperatures of pure components are required, while the information about the interactions in the b...
Atele-Williams , Tosan; Marsh , Stephen
2017-01-01
Part 7: IFIPTM 2017 Graduate Symposium; International audience; Information has been an essential element in the development of collaborative and cooperative models, from decision making to the attainmentof varying goals, people are adept at making judgment on the trustworthiness of information, based on knowledge and understanding of a normative model of information. Contemporary narrative especially in high-impact contexts like politics, health, business, government and technology, is erodi...
Mehta, Shalin B.; Sheppard, Colin J. R.
2010-05-01
Various methods that use large illumination aperture (i.e. partially coherent illumination) have been developed for making transparent (i.e. phase) specimens visible. These methods were developed to provide qualitative contrast rather than quantitative measurement-coherent illumination has been relied upon for quantitative phase analysis. Partially coherent illumination has some important advantages over coherent illumination and can be used for measurement of the specimen's phase distribution. However, quantitative analysis and image computation in partially coherent systems have not been explored fully due to the lack of a general, physically insightful and computationally efficient model of image formation. We have developed a phase-space model that satisfies these requirements. In this paper, we employ this model (called the phase-space imager) to elucidate five different partially coherent systems mentioned in the title. We compute images of an optical fiber under these systems and verify some of them with experimental images. These results and simulated images of a general phase profile are used to compare the contrast and the resolution of the imaging systems. We show that, for quantitative phase imaging of a thin specimen with matched illumination, differential phase contrast offers linear transfer of specimen information to the image. We also show that the edge enhancement properties of spiral phase contrast are compromised significantly as the coherence of illumination is reduced. The results demonstrate that the phase-space imager model provides a useful framework for analysis, calibration, and design of partially coherent imaging methods.
High temperature phase equilibria and phase diagrams
Kuo, Chu-Kun; Yan, Dong-Sheng
2013-01-01
High temperature phase equilibria studies play an increasingly important role in materials science and engineering. It is especially significant in the research into the properties of the material and the ways in which they can be improved. This is achieved by observing equilibrium and by examining the phase relationships at high temperature. The study of high temperature phase diagrams of nonmetallic systems began in the early 1900s when silica and mineral systems containing silica were focussed upon. Since then technical ceramics emerged and more emphasis has been placed on high temperature
Micropatch Antenna Phase Shifting
National Research Council Canada - National Science Library
Thursby, Michael
2000-01-01
.... We have been looking at the ability of embedded element to adjust the phase shift seen by the element with the goal of being able to remove the phase shifting devices from the antenna and replace...
Micropatch Antenna Phase Shifting
National Research Council Canada - National Science Library
Thursby, Michael
1999-01-01
.... We have been looking at the ability of embedded element to adjust the phase shift seen by the element wit the goal of being able to remove the phase shifting devices from the antenna and replace...
Digital quadrature phase detection
Smith, J.A.; Johnson, J.A.
1992-05-26
A system for detecting the phase of a frequency or phase modulated signal that includes digital quadrature sampling of the frequency or phase modulated signal at two times that are one quarter of a cycle of a reference signal apart, determination of the arctangent of the ratio of a first sampling of the frequency or phase modulated signal to the second sampling of the frequency or phase modulated signal, and a determination of quadrant in which the phase determination is increased by 2[pi] when the quadrant changes from the first quadrant to the fourth quadrant and decreased by 2[pi] when the quadrant changes from the fourth quadrant to the first quadrant whereby the absolute phase of the frequency or phase modulated signal can be determined using an arbitrary reference convention. 6 figs.
Second phase in steel AISI 316 tested at 8000C
International Nuclear Information System (INIS)
Silveira, V.L.A.; Monteiro, S.N.
The nature of second phases in type 316 stainless steel samples tested in creep to rupture at 800 0 C has been discussed. These phases were identified by experimental techniques completed with the available information in the literature. The role of these phases in the creep properties of the type 316 steel at 800 0 C is analysed [pt
78 FR 76789 - Additional Connect America Fund Phase II Issues
2013-12-19
... inspection and copying during normal business hours in the FCC Reference Information Center, Portals II, 445... Phase I to Phase II. 2. Timing of Phase II Support Disbursements. In the USF/ICC Transformation Order... language in paragraph 180 of the USF/ICC Transformation Order. We now seek to more fully develop the record...
Bowers, Michael T
1979-01-01
Gas Phase Ion Chemistry, Volume 2 covers the advances in gas phase ion chemistry. The book discusses the stabilities of positive ions from equilibrium gas-phase basicity measurements; the experimental methods used to determine molecular electron affinities, specifically photoelectron spectroscopy, photodetachment spectroscopy, charge transfer, and collisional ionization; and the gas-phase acidity scale. The text also describes the basis of the technique of chemical ionization mass spectrometry; the energetics and mechanisms of unimolecular reactions of positive ions; and the photodissociation
Brookner, E.
1985-02-01
The operating principles, technology, and applications of phased-array radars are reviewed and illustrated with diagrams and photographs. Consideration is given to the antenna elements, circuitry for time delays, phase shifters, pulse coding and compression, and hybrid radars combining phased arrays with lenses to alter the beam characteristics. The capabilities and typical hardware of phased arrays are shown using the US military systems COBRA DANE and PAVE PAWS as examples.
International Nuclear Information System (INIS)
Anon.
1991-01-01
RIMNET (Radioactive Incident Monitoring Network) is the key element in the British government's National Response Plan, which was established in the wake of the Chernobyl accident. It raises an alert if abnormal radioactivity increases are detected and provides a national communications system through which it is intended to give information and advice rapidly to the public, local authorities and other interested parties. In the event of an overseas nuclear accident with potential consequences for the UK, a technical co-ordination centre would be convened which would have at its disposal a pre-established database to hold the radiological data that would need to be collected at the time of the incident to assess its impact. Phase 1 of RIMET has been operating since 1988. It uses manually read radiation monitors. The second phase consists of: doubling the number of monitoring sites from 46 to 92; fully automating data analysis and collection; and providing more powerful information systems and friendly displays to help those advising and informing the public. Those supplying data to the system, for example on foodstuff analysis, will do so via portable computers, and only minimum manual intervention will be required from those using the system to support incident response. The end result should be one of the most advanced systems of its kind in the world, giving continuous automated monitoring of radioactivity levels throughout the UK and integrating the data with meteorological information to predict the effect of incidents. (author)
Computation of Phase Equilibrium and Phase Envelopes
DEFF Research Database (Denmark)
Ritschel, Tobias Kasper Skovborg; Jørgensen, John Bagterp
formulate the involved equations in terms of the fugacity coefficients. We present expressions for the first-order derivatives. Such derivatives are necessary in computationally efficient gradient-based methods for solving the vapor-liquid equilibrium equations and for computing phase envelopes. Finally, we......In this technical report, we describe the computation of phase equilibrium and phase envelopes based on expressions for the fugacity coefficients. We derive those expressions from the residual Gibbs energy. We consider 1) ideal gases and liquids modeled with correlations from the DIPPR database...... and 2) nonideal gases and liquids modeled with cubic equations of state. Next, we derive the equilibrium conditions for an isothermal-isobaric (constant temperature, constant pressure) vapor-liquid equilibrium process (PT flash), and we present a method for the computation of phase envelopes. We...
International Nuclear Information System (INIS)
1997-02-01
The document summarizes the Information Circulars published by the IAEA for the purpose of bringing matters of general interest to the attention of all Member States. This revision contains INFCIRCs published up to February 1997, grouped by field of activity. A complete list of information circulars in numerical order is given in an annex
International Nuclear Information System (INIS)
2002-05-01
Information circulars are published from time to time under the symbol INFCIRC/... for the purpose of bringing matters of general interest to the attention of all Members of the Agency. The present revision contains INFCIRCs published up to the end of April 2002. A complete numerical list of information circulars is reproduced with their titles in the Annex
International Nuclear Information System (INIS)
1999-06-01
The document summarizes the Information Circulars published by the IAEA for the purpose of bringing matters of general interest to the attention of all Member States. This revision contains INFCIRCs published up to the end of May 1999, grouped by field of activity. A complete list of information circulars in numerical order is given in an annex
International Nuclear Information System (INIS)
1994-08-01
Information circulars are published from time to time under the symbol INFCIRC/... for the purpose of bringing matters of general interest to the attention of all Members of the Agency. The present revision contains INFCIRCs published up to mid-August 1994. A complete numerical list of information circulars is reproduced with their titles in the Annex
International Nuclear Information System (INIS)
1992-08-01
The document summarizes the Information Circulars published by the IAEA for the purpose of bringing matters of general interest to the attention of all Members of the Agency. This revision contains INFCIRCs published up to mid-August 1992. A complete numerical lift of Information Circulars with their titles is reproduced in an Annex
African Journals Online (AJOL)
USER
This study investigated the effectiveness and impact of library instruction (GST 111 – the use of ... information literacy of the students for lifelong .... competency of freshman business students of a ... strategies, information sources, proper use of library ..... P. Remark. Library skill. Secondary school attended. 47.5846. 01.3600.
International Nuclear Information System (INIS)
Sikka, S.K.; Vohra, Y.K.; Chidambaram, R.
1982-01-01
The subject is covered in sections, entitled: introduction; occurrence and some systematics of omega phase (omega phase in Ti, Zr and Hf under high pressures; omega phase in Group IV transition metal alloys; omega in other systems; omega embryos at high temperatures); crystallography (omega structure; relationship of ω-structure to bcc (β) and hcp (α) structures); physical properties; kinetics of formation, synthesis and metastability of omega phase (kinetics of α-ω transformation under high pressures; kinetics of β-ω transformation; synthesis and metastability studies); electronic structure of omega phase (electronic structure models; band structure calculations; theoretical results and experimental studies); electronic basis for omega phase stability (unified phase diagram; stability of omega phase); omega phase formation under combined thermal and pressure treatment in alloys (Ti-V alloys under pressure - a prototype case study; P-X phase diagrams for alloys; transformation mechanisms and models for diffuse omega phase (is omega structure a charge density distortion of the bcc phase; nature of incommensurate ω-structure and models for diffuse scattering); conclusion. (U.K.)
Information technology: management issues in outsource contracts.
2008-01-01
This study concerns the investigation of management issues within information technology outsourcing contracts. The information technology outsourcing life cycle is used as the flow structure for the investigation. The associated user expectations that occur in each of the phases of the information technology outsourcing life cycle are identified. Following the identification of the management and user expectation issues in each phase of the outsource life cycle, the “Coetzee solution framewo...
Zhao, Bo
Phase transitions are one of the most exciting physical phenomena ever discovered. The understanding of phase transitions has long been of interest. Recently eigenstate phase transitions have been discovered and studied; they are drastically different from traditional thermal phase transitions. In eigenstate phase transitions, a sharp change is exhibited in properties of the many-body eigenstates of the Hamiltonian of a quantum system, but not the thermal equilibrium properties of the same system. In this thesis, we study two different types of eigenstate phase transitions. The first is the eigenstate phase transition within the ferromagnetic phase of an infinite-range spin model. By studying the interplay of the eigenstate thermalization hypothesis and Ising symmetry breaking, we find two eigenstate phase transitions within the ferromagnetic phase: In the lowest-temperature phase the magnetization can macroscopically oscillate by quantum tunneling between up and down. The relaxation of the magnetization is always overdamped in the remainder of the ferromagnetic phase, which is further divided into phases where the system thermally activates itself over the barrier between the up and down states, and where it quantum tunnels. The second is the many-body localization phase transition. The eigenstates on one side of the transition obey the eigenstate thermalization hypothesis; the eigenstates on the other side are many-body localized, and thus thermal equilibrium need not be achieved for an initial state even after evolving for an arbitrary long time. We study this many-body localization phase transition in the strong disorder renormalization group framework. After setting up a set of coarse-graining rules for a general one dimensional chain, we get a simple "toy model'' and obtain an almost purely analytical solution to the infinite-randomness critical fixed point renormalization group equation. We also get an estimate of the correlation length critical exponent nu
Informal information for web-based engineering catalogues
Allen, Richard D.; Culley, Stephen J.; Hicks, Ben J.
2001-10-01
Success is highly dependent on the ability of a company to efficiently produce optimal designs. In order to achieve this companies must minimize time to market and possess the ability to make fully informed decisions at the early phase of the design process. Such decisions may include the choice of component and suppliers, as well as cost and maintenance considerations. Computer modeling and electronic catalogues are becoming the preferred medium for the selection and design of mechanical components. In utilizing these techniques, the designer demands the capability to identify, evaluate and select mechanical components both quantitatively and qualitatively. Quantitative decisions generally encompass performance data included in the formal catalogue representation. It is in the area of qualitative decisions that the use of what the authors call 'Informal Information' is of crucial importance. Thus, 'Informal Information' must often be incorporated into the selection process and selection systems. This would enable more informed decisions to be made quicker, without the need for information retrieval via discussion with colleagues in the design environment. This paper provides an overview of the use of electronic information in the design of mechanical systems, including a discussion of limitations of current technology. The importance of Informal Information is discussed and the requirements for association with web based electronic catalogues are developed. This system is based on a flexible XML schema and enables the storage, classification and recall of Informal Information packets. Furthermore, a strategy for the inclusion of Informal Information is proposed, and an example case is used to illustrate the benefits.
DEFF Research Database (Denmark)
Golestan, Saeed; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez
2017-01-01
Single-phase phase-locked loops (PLLs) are popular for the synchronization and control of single-phase gridconnected converters. They are also widely used for monitoring and diagnostic purposes in the power and energy areas. In recent years, a large number of single-phase PLLs with different stru......-PLLs). The members of each category are then described and their pros and cons are discussed. This work provides a deep insight into characteristics of different single-phase PLLs and, therefore, can be considered as a reference for researchers and engineers....
International Nuclear Information System (INIS)
Hartle, J.B.
1995-01-01
In usual quantum theory, the information available about a quantum system is defined in terms of the density matrix describing it on a spacelike surface. This definition must be generalized for extensions of quantum theory which neither require, nor always permit, a notion of state on a spacelike surface. In particular, it must be generalized for the generalized quantum theories appropriate when spacetime geometry fluctuates quantum mechanically or when geometry is fixed but not foliable by spacelike surfaces. This paper introduces a four-dimensional notion of the information available about a quantum system's boundary conditions in the various sets of decohering, coarse-grained histories it may display. This spacetime notion of information coincides with the familiar one when quantum theory is formulable in terms of states on spacelike surfaces but generalizes this notion when it cannot be so formulated. The idea of spacetime information is applied in several contexts: When spacetime geometry is fixed the information available through alternatives restricted to a fixed spacetime region is defined. The information available through histories of alternatives of general operators is compared to that obtained from the more limited coarse grainings of sum-over-histories quantum mechanics that refer only to coordinates. The definition of information is considered in generalized quantum theories. We consider as specific examples time-neutral quantum mechanics with initial and final conditions, quantum theories with nonunitary evolution, and the generalized quantum frameworks appropriate for quantum spacetime. In such theories complete information about a quantum system is not necessarily available on any spacelike surface but must be searched for throughout spacetime. The information loss commonly associated with the ''evolution of pure states into mixed states'' in black hole evaporation is thus not in conflict with the principles of generalized quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Bruce, G.M.; Buddenbaum, J.E.; Lamb, J.K.; Widner, T.E.
1993-09-01
The Phase I feasibility study has focused on determining the availability of information for estimating exposures of the public to chemicals and radionuclides released as a result of historical operation of the facilities at the Oak Ridge Reservation (ORR). The estimation of such past exposures is frequently called dose reconstruction. The initial project tasks, Tasks 1 and 2 were designed to identify and collect information that documents the history of activities at the ORR that resulted in the release of contamination and to characterize the availability of data that could be used to estimate the magnitude of the contaminant releases or public exposures. A history of operations that are likely to have generated off-site releases has been documented as a result of Task 1 activities. The activities required to perform this task involved the extensive review of historical operation records and interviews with present and past employees as well as other knowledgeable individuals. The investigation process is documented in this report. The Task 1 investigations have led to the documentation of an overview of the activities that have taken place at each of the major complexes, including routine operations, waste management practices, special projects, and accidents and incidents. Historical activities that appear to warrant the highest priority in any further investigations were identified based on their likely association with off-site emissions of hazardous materials as indicated by the documentation reviewed or information obtained in interviews.
Glare Spot Phase Doppler Anemometry
Hespel, Camille; Ren, Kuanfang; Gréhan, Gérard; Onofri, Fabrice
2007-06-01
The Phase Doppler anemometry has been developed to measure simultaneously the velocity and the size of droplets. The measurement of the refractive index would be also interesting since it depends on the temperature and the composition of the particle and its measurement permits both to increase the quality of the diameter measurement and to obtain information on the temperature and/or the composition of the droplets. In this paper, we introduce a Glare Spot Phase Doppler Anemometry which uses two large beams. In this case, the images of the particle formed by the reflected and refracted light, known as glare spots, are separated in space. When a particle passes in the probe volume, the two parts in a signal obtained by a detector in forward direction are then separated in time. If two detectors are used the phase differences between two signals, the distance and the intensity ratio of reflected and refracted parts can be obtained and they provide rich information about the particle diameter and its refractive index, as well as its velocity. This paper is devoted to the numerical study of such a configuration with two theoretical models: geometrical optics and rigorous electromagnetism solution.
International Nuclear Information System (INIS)
1971-01-01
The Agency has a statutory mandate to foster 'the exchange of scientific and technical information on the peaceful uses of atomic energy'. The prime responsibility for this work within the Agency lies with the Division of Scientific and Technical Information, a part of the Department of Technical Operations. The Division accomplishes its task by holding conferences and symposia (Scientific Conferences Section), through the Agency Library, by publishing scientific journals, and through the International Nuclear Information System (INIS). The Computer Section of the Division, which offers services to the Agency as a whole, provides resources for the automation of data storage and retrieval. (author)
Capet, Philippe
2014-01-01
During the reception of a piece of information, we are never passive. Depending on its origin and content, from our personal beliefs and convictions, we bestow upon this piece of information, spontaneously or after reflection, a certain amount of confidence. Too much confidence shows a degree of naivety, whereas an absolute lack of it condemns us as being paranoid. These two attitudes are symmetrically detrimental, not only to the proper perception of this information but also to its use. Beyond these two extremes, each person generally adopts an intermediate position when faced with the recep
Phase transitions in finite systems
Energy Technology Data Exchange (ETDEWEB)
Chomaz, Ph. [Grand Accelerateur National d' Ions Lourds (GANIL), DSM-CEA / IN2P3-CNRS, 14 - Caen (France); Gulminelli, F. [Caen Univ., 14 (France). Lab. de Physique Corpusculaire
2002-07-01
In this series of lectures we will first review the general theory of phase transition in the framework of information theory and briefly address some of the well known mean field solutions of three dimensional problems. The theory of phase transitions in finite systems will then be discussed, with a special emphasis to the conceptual problems linked to a thermodynamical description for small, short-lived, open systems as metal clusters and data samples coming from nuclear collisions. The concept of negative heat capacity developed in the early seventies in the context of self-gravitating systems will be reinterpreted in the general framework of convexity anomalies of thermo-statistical potentials. The connection with the distribution of the order parameter will lead us to a definition of first order phase transitions in finite systems based on topology anomalies of the event distribution in the space of observations. Finally a careful study of the thermodynamical limit will provide a bridge with the standard theory of phase transitions and show that in a wide class of physical situations the different statistical ensembles are irreducibly inequivalent. (authors)
Phase transitions in finite systems
International Nuclear Information System (INIS)
Chomaz, Ph.; Gulminelli, F.
2002-01-01
In this series of lectures we will first review the general theory of phase transition in the framework of information theory and briefly address some of the well known mean field solutions of three dimensional problems. The theory of phase transitions in finite systems will then be discussed, with a special emphasis to the conceptual problems linked to a thermodynamical description for small, short-lived, open systems as metal clusters and data samples coming from nuclear collisions. The concept of negative heat capacity developed in the early seventies in the context of self-gravitating systems will be reinterpreted in the general framework of convexity anomalies of thermo-statistical potentials. The connection with the distribution of the order parameter will lead us to a definition of first order phase transitions in finite systems based on topology anomalies of the event distribution in the space of observations. Finally a careful study of the thermodynamical limit will provide a bridge with the standard theory of phase transitions and show that in a wide class of physical situations the different statistical ensembles are irreducibly inequivalent. (authors)
Geometric phases and quantum computation
International Nuclear Information System (INIS)
Vedral, V.
2005-01-01
Full text: In my lectures I will talk about the notion of the geometric phase and explain its relevance for both fundamental quantum mechanics as well as quantum computation. The phase will be at first introduced via the idea of Pancharatnam which involves interference of three or more light beams. This notion will then be generalized to the evolving quantum systems. I will discuss both pure and mixed states as well as unitary and non-unitary evolutions. I will also show how the concept of the vacuum induced geometric phase arises in quantum optics. A simple measurement scheme involving a Mach Zehnder interferometer will be presented and will be used to illustrate all the concepts in the lecture. Finally, I will expose a simple generalization of the geometric phase to evolving degenerate states. This will be seen to lead to the possibility of universal quantum computation using geometric effects only. Moreover, this contains a promise of intrinsically fault tolerant quantum information processing, whose prospects will be outlined at the end of the lecture. (author)
Phase transition phenomenon: A compound measure analysis
Kang, Bo Soo; Park, Chanhi; Ryu, Doojin; Song, Wonho
2015-06-01
This study investigates the well-documented phenomenon of phase transition in financial markets using combined information from both return and volume changes within short time intervals. We suggest a new measure for the phase transition behaviour of markets, calculated as a return distribution conditional on local variance in volume imbalance, and show that this measure successfully captures phase transition behaviour under various conditions. We analyse the intraday trade and quote dataset from the KOSPI 200 index futures, which includes detailed information on the original order size and the type of each initiating investor. We find that among these two competing factors, the submitted order size yields more explanatory power on the phenomenon of market phase transition than the investor type.
International Nuclear Information System (INIS)
Wide, L.
1977-01-01
Solid phase coupled antibodies were introduced to facilitate the separation of bound and free labelled ligand in the competitive inhibition radioimmunoassay. Originally, the solid matrix used was in the form of small particles and since then a number of different matrices have been used such as very fine powder particles, gels, paper and plastic discs, magnetic particles and the inside surface of plastic tubes. The coupling of antibodies may be that of a covalent chemical binding, a strong physical adsorbtion, or an immunological binding to a solid phase coupled antigen. New principles of radioimmunoassay such as the solid phase sandwich techniques and the immunoradiometric assay were developped from the use of solid phase coupled antigens and antibodies. The solid phase sandwich techniques are reagent excess methods with a very wide applicability. Several of the different variants of solid phase techniques are suitable for automation. Advantages and disadvantages of solid phase radioimmunoassays when compared with those using soluble reagents are discussed. (orig.) [de
Glückstad, Jesper
2009-01-01
Generalized Phase Contrast elevates the phase contrast technique not only to improve phase imaging but also to cross over and interface with diverse and seemingly disparate fields of contemporary optics and photonics. This book presents a comprehensive introduction to the Generalized Phase Contrast (GPC) method including an overview of the range of current and potential applications of GPC in wavefront sensing and phase imaging, structured laser illumination and image projection, optical trapping and manipulation, and optical encryption and decryption. The GPC method goes further than the restrictive assumptions of conventional Zernike phase contrast analysis and achieves an expanded range of validity beyond weak phase perturbations. The generalized analysis yields design criteria for tuning experimental parameters to achieve optimal performance in terms of accuracy, fidelity and light efficiency. Optimization can address practical issues, such as finding an optimal spatial filter for the chosen application, ...
How Informed Are Informal Educators?
Lederman, Norman G.; Niess, Margaret L.
1998-01-01
Explores current reforms in both mathematics and science education that emphasize the importance of learning in informal settings. Suggests that informal education must include planned and purposeful attempts to facilitate students' understanding of mathematics and science in community settings other than the local school. (Author/CCM)
International Nuclear Information System (INIS)
Sachdev, S.
1999-01-01
Phase transitions are normally associated with changes of temperature but a new type of transition - caused by quantum fluctuations near absolute zero - is possible, and can tell us more about the properties of a wide range of systems in condensed-matter physics. Nature abounds with phase transitions. The boiling and freezing of water are everyday examples of phase transitions, as are more exotic processes such as superconductivity and superfluidity. The universe itself is thought to have passed through several phase transitions as the high-temperature plasma formed by the big bang cooled to form the world as we know it today. Phase transitions are traditionally classified as first or second order. In first-order transitions the two phases co-exist at the transition temperature - e.g. ice and water at 0 deg., or water and steam at 100 deg. In second-order transitions the two phases do not co-exist. In the last decade, attention has focused on phase transitions that are qualitatively different from the examples noted above: these are quantum phase transitions and they occur only at the absolute zero of temperature. The transition takes place at the ''quantum critical'' value of some other parameter such as pressure, composition or magnetic field strength. A quantum phase transition takes place when co-operative ordering of the system disappears, but this loss of order is driven solely by the quantum fluctuations demanded by Heisenberg's uncertainty principle. The physical properties of these quantum fluctuations are quite distinct from those of the thermal fluctuations responsible for traditional, finite-temperature phase transitions. In particular, the quantum system is described by a complex-valued wavefunction, and the dynamics of its phase near the quantum critical point requires novel theories that have no analogue in the traditional framework of phase transitions. In this article the author describes the history of quantum phase transitions. (UK)
Unwrapped phase inversion with an exponential damping
Choi, Yun Seok
2015-07-28
Full-waveform inversion (FWI) suffers from the phase wrapping (cycle skipping) problem when the frequency of data is not low enough. Unless we obtain a good initial velocity model, the phase wrapping problem in FWI causes a result corresponding to a local minimum, usually far away from the true solution, especially at depth. Thus, we have developed an inversion algorithm based on a space-domain unwrapped phase, and we also used exponential damping to mitigate the nonlinearity associated with the reflections. We construct the 2D phase residual map, which usually contains the wrapping discontinuities, especially if the model is complex and the frequency is high. We then unwrap the phase map and remove these cycle-based jumps. However, if the phase map has several residues, the unwrapping process becomes very complicated. We apply a strong exponential damping to the wavefield to eliminate much of the residues in the phase map, thus making the unwrapping process simple. We finally invert the unwrapped phases using the back-propagation algorithm to calculate the gradient. We progressively reduce the damping factor to obtain a high-resolution image. Numerical examples determined that the unwrapped phase inversion with a strong exponential damping generated convergent long-wavelength updates without low-frequency information. This model can be used as a good starting model for a subsequent inversion with a reduced damping, eventually leading to conventional waveform inversion.
Informed consent: information or knowledge?
Berger, Ken
2003-01-01
A fiduciary relationship should be nurtured between patient and physician. This requires effective communication throughout all aspects of care - especially pertaining to treatment decisions. In the context of illness as experienced by the patient a unique set of circumstances is presented. However, communication in an illness context is fraught with problems. The patient is vulnerable and the situation may be overwhelming. Voluminous amounts of information are available to patients from a host of health care providers, family members, support groups, advocacy centers, books, journals, and the internet. Often conflicting and confusion, frequently complex, this information may be of greater burden than benefit. Some information is of high validity and reliability while other information is of dubious reliability. The emotional freight of bad news may further inhibit understanding. An overload of information may pose an obstacle in decision-making. To facilitate the transformation of information into knowledge, the health care provider must act on some occasions as a filter, on other occasions as a conduit, and on still other occasions simply as a reservoir. The evolution of patient rights to receive or refuse treatment, the right to know or not to know calls for a change in processing of overwhelming information in our modem era. In this paper we will discuss the difference between information and knowledge. How can health care providers ensure they have given their patients all necessary and sufficient information to make an autonomous decision? How can they facilitate the transformation of information into knowledge? The effect of knowledge to consent allows a more focused, relevant and modern approach to choice in health care.
African Journals Online (AJOL)
USER
1996-10-01
Oct 1, 1996 ... locate and access information from current awareness sources such as newspapers and radio. Legislators (35%) ... law-making and supervision for a viable democracy .... from a parliamentary library is a major concern for.
Social Security Administration — The Position Information Data Asset provides the ability to search for active SSA position descriptions using various search criteria. An individual may search by PD...
African Journals Online (AJOL)
USER
information but also quickly access and retrieve large volume of ... created their management becomes a challenge for most institutions .... continuous upgrade of operating system, .... Tammro, A.M (2006) the Digital Library Users: Case.