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Quantum corrections for Boltzmann equation

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Science China(Physics,Mechanics & Astronomy) 2008年第9期51卷 1229-1239页

作者： M. levy PETEr Department of Physics New York University

We present the lowest order quantum correction to the semiclassical Boltzmann distribution function,and the equation satisfied by this correction is given. Our equation for the quantum correction is obtained from the conventional quantum Boltzmann equation by explicitly expressing the Planck constant in the gradient approximation,and the quantum Wigner distribution function is expanded in pow-ers of Planck constant,too. The negative quantum correlation in the Wigner dis-tribution function which is just the quantum correction terms is naturally singled out,thus obviating the need for the Husimi’s coarse grain averaging that is usually done to remove the negative quantum part of the Wigner distribution function. We also discuss the classical limit of quantum thermodynamic entropy in the above framework.

关键词： quantum Boltzmann equation Wigner distribution function quantum correction

Development of an operational land water mask for MODIS Collection 6,and influence on downstream data products

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International journal of Digital Earth 2017年第2期10卷 207-218页

作者： M.L.Carroll C.M.DiMiceli j.r.G.Townshend r.A.Sohlberg A.I.Elders S.Devadiga A.M.Sayer r.C.levy NASA/GSFC Biospheric Sciences Laboratory GreenbeltMDUSA Science Systems and Applications Inc. LanhamMDUSA Department of Geographical Sciences University of MarylandCollege ParkMDUSA Atmospheric Oceanic and Earth SciencesGeorge Mason UniversityFairfaxVAUSA NASA/GSFC Terrestrial Information Systems Laboratory GreenbeltMDUSA fGoddard Earth Sciences Technology and research Universities Space Research AssociationGreenbeltMDUSA NASA/GSFC Climate and radiation Laboratory GreenbeltMDUSA

Data from the Moderate resolution Imaging Spectro-radiometer(MODIS)on-board the Earth Observing System Terra and Aqua satellites are processed using a land water mask to determine when an algorithm no longer needs to be run or when an algorithm needs to follow a different *** the fourth reprocessing(Collection 6(C6))the MODIS team replaced the 1 km water mask with a 500 m water mask for improved representation of the continental *** new water mask represents more small water bodies for an overall increase in water surface from 1%to 2%of the continental *** this is still a small fraction of the overall global surface area the increase is more dramatic in certain areas such as the Arctic and Boreal regions where there are dramatic increases in water surface area in the new *** products generated by the on-going C6 reprocessing using the new land water mask show significant impact in areas with high concentrations of change in the land water *** differences between the Collection 5(C5)and C6 water masks and the impact of these differences on the MOD04 aerosol product and the MOD11 land surface temperature product are shown.

关键词： Earth observation image processing land cover remote sensing water resources

ADVANCES IN SUSTAINABLE SECUrITY SYSTEMS ENGINEErING WITH DrAMA THEOrY (DT) Ⅱ

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journal of Systems Science and Systems Engineering 2009年第4期18卷 403-422页

作者： jason K. levy Nigel HOWArD Wilder School of Government and Public Affairs Virginia Commonwealth University Sheffield Hallam University

We put forth Drama Theory II （DT II） as a formal multiple participant decision making framework that can be used to systematically model complex security challenges, and advance the field of Sustainable Security Systems Engineering. DT II is defined as a theory of ＂large world＂ pre-game communication and equilibrium selection. While game theoretic tools have been widely applied to resolve environmental conflicts and promote global security, traditional game theory assumes that decision makers, options, and preferences are fixed. A mathematical treatment of key drama theoretic concepts （i.e. positions, intentions, doubts and dilemmas） is provided. The dynamics of the drama theoretic process are discussed and the expected equilibrium set is derived. The fundamental theorem of drama theory is proven and all theoretical results are applied to promote sustainable security solutions. It is emphasized that DT II represents a flexible systems engineering technique to address time-sensitive, multi-faceted, and complex multiple participant negotiations.

关键词： Drama Theory II sustainable security systems engineering game theory

Accelerating CFD–DEM simulation of processes with wide particle size distributions

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Particuology 2014年第1期12卷 113-121页

作者： Tamir Brosh Haim Kalman Avi levy Pearlstone Centre for Aeronautical Engineering Studies Department of Mechanical Engineering Ben-Gurion University of the Negev School of Mechanical and Systems Engineering Stephenson Building Claremont Road Newcastle University

Sizereduction systems have been extensively used in industry for many years. Nevertheless, reliable engi neering tools to be used to predict the comminution of particles are scarce. Computational fluid dynamics （CFD）discrete element model （DEM） numerical simulation may be used to predict such a complex phe nomenon and therefore establish a proper design and optimization model for comminution systems, They may also be used to predict attrition in systems where particle attrition is significant. Therefore, empirical comminution functions （which are applicable for any attrition/comminution process）, such as： strength distribution, selection, equivalence, breakage, and fatigue, have been integrated into the three dimensional CFDDEM simulation tool. The main drawback of such a design tool is the long computational time required owing to the large number of particles and the minute timestep required to maintain a steady solution while simulating the flow of particulate materials with very fine particles. The present study developed several methods to accelerate CFDDEM simulations： reducing the num ber of operations carried out at the singleparticle level, constructing a DEM grid detached from the CFD grid enabling a no binary search, generating a subgrid within the DEM grid to enable a no binary search for fine particles, and increasing the computational timestep and eliminating the finest particles in the simulation while still tracking their contribution to the process. The total speedup of the simulation process without the elimination of the finest particles was a factor of about 17. The elimination of the finest particles gave additional speedup of a factor of at least 18. Therefore, the simulation of a grinding process can run at least 300 times faster than the conventional method in which a standard no binary search is employed and the smallest particles are tracked.

关键词： Computational fluid dynamicsDiscrete element modelSearch algorithmIncreased time-step

Posttesticular sperm maturation, infertility, and hypercholesterolemia

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Asian journal of Andrology 2015年第5期17卷 742-748,I0007页

作者： Marjorie Whitfield Xavier PoUet-Villard rachel levy joel r Drevet Fabrice Saez Team 'Mechanisms of post-testicular infertility' Genetique Reproduction et Developpement UMR CNRS 6293 INSERM U1103 Clermont Universite 24 Avenue des Landais BP80026 63171 Aubiere Codex France Service d'Histologie-Embryologie-Cytogenetique-CECOS Hopital Jean Verdier (AP-HP) Avenue du 14 Juillet 93143 Bondy France Service de Medecine de la reproduction Hopital Tenon (AP-HP) 4 Rue de la Chine 75020 Paris France Unite de recherche en Epidemiologie Nutritionnelle INSERM U557 INRA CNAM Universite Paris 13 CRNH IdF 93017 Bobigny France

Cholesterol is a key molecule in the mammalian physiology of especial particular importance for the reproductive system as it is the common precursor for steroid hormone synthesis. Cholesterol is also a recognized modulator of sperm functions, not only at the level of gametogenesis. Cholesterol homeostasis regulation is crucial for posttesticular sperm maturation, and imbalanced cholesterol levels may particularly affect these posttesticular events. Metabolic lipid disorders （dyslipidemia） affect male fertility but are most of the time studied from the angle of endocrine/testicular consequences. This review will focus on the deleterious effects of a particular dyslipidemia, Le., hypercholesterolemia, on posttesticular maturation of mammalian spermatozoa.

关键词： cholesterol dyslipidemia epididymis fertility posttesticular maturation spermatozoa

Genome evolution in allopolyploid wheat—a revolutionary reprogramming followed by gradual changes

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journal of Genetics and Genomics 2009年第9期36卷 511-518页

作者： Moshe Feldman Avraham A. levy Plant Sciences The Weizmann Institute of Science

Allopolyploidy accelerates genome evolution in wheat in two ways： 1） allopolyploidization triggers rapid genome alterations （revolutionary changes） through the instantaneous generation of a variety of cardinal genetic and epigenetic changes, and 2） the allopolyploid condition facilitates sporadic genomic changes during the life of the species （evolutionary changes） that are not attainable at the diploid level. The revolutionary alterations, occurring during the formation of the allopolyploid and leading to rapid cytological and genetic diploidization, facilitate the successful establishment of the newly formed allopolyploid in nature. On the other hand, the evolutionary changes, occurring during the life of the allopolyploids, increase the intra-specific genetic diversity, and consequently, increased fimess, adaptability and competitiveness. These phenomena, emphasizing the dynamic plasticity of the allopolyploid wheat genome with regards to both structure and function, are described and discussed in this review.

关键词： allopolyploidization cytological diploidization epigenetics genetic diploidizafion Triticum wheat

The initial stages of Li_(2)O_(2) formation during oxygen reduction reaction in Li-O_(2) batteries:The significance of Li_(2)O_(2) in charge-transfer reactions within devices

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journal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela M.josepetti Bianca P.Sousa Simone A.j.rodrigues renato G.Freitas Gustavo Doubek Advanced Energy Storage Division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of Physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(Orr)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)O_(2))was observed with operando raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)O_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)O_(2) forms a hetero-phase between Li_(2)O_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)O_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-O_(2)battery Operando raman analysis Equivalent circuit modeling Time-constant distribution

INTELLIGENT SECUrITY SYSTEMS ENGINEErING FOr MODELING FIrE CrITICAL INCIDENTS:TOWArDS SUSTAINABLE SECUrITY

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journal of Systems Science and Systems Engineering 2009年第4期18卷 477-488页

作者： Ali ASGArY Ali SADEGHI NAINI jason levy Emergency Management York University Faculty of Geography University of Tehran Department of Electrical and Computer Engineering University of Western Ontario Homeland Security and Emergency Preparedness Virginia Commonwealth University

An intelligent security systems engineering approach is used to analyze fire and explosive critical incidents, a growing concern in urban communities. A feed-forward back-propagation neural network models the damages arising from these critical incidents. The overall goal is to promote fire safety and sustainable security. The intelligent security systems engineering prediction model uses a fully connected multilayer neural network, and considers a number of factors related to the fire or explosive incident including the type of property affected, the time of day, and the ignition source. The network was trained on a large number of critical incident records reported in Toronto, Canada between 2000 and 2006. Our intelligent security systems engineering approach can help emergency responders by improving cr^tical incident analysis, sustainable security, and fire risk management.

关键词： Intelligent security systems engineering fire feed-forward neural networks critical incidents

Effect of oxygen and nitrogen functionalization on the physical and electronic structure of graphene

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Nano research 2015年第8期8卷 2620-2635页

作者： Alexander j. Marsden Peter Brommer james j. Mudd M. Adam Dyson robert Cook Maria Asensio jose Avila Ana levy jeremy Sloan David Quigley Gavin r. Bell Neil r. Wilson Department of Physics University of Warwick Coventry UK Centre for Scientific Computing University of Warwick Coventry UK Synchrotron SOLEIL L'Orme des Merisiers Saint Aubin-BP 48 91192 Gifsur Yvette Cedex France

Covalent functionalization of graphene offers opportunities for tailoring its properties and is an unavoidable consequence of some graphene synthesis techniques. However, the changes induced by the functionalization are not well understood. By using atomic sources to control the extent of the oxygen and nitrogen functionalization, we studied the evolution in the structure and properties at the atomic scale. Atomic oxygen reversibly introduces epoxide groups whilst, under similar conditions, atomic nitrogen irreversibly creates diverse functionalities including substitutional, pyridinic, and pyrrolic nitrogen. Atomic oxygen leaves the Fermi energy at the Dirac point （i.e., undoped）, whilst atomic nitrogen results in a net n-doping; however, the experimental results are consistent with the dominant electronic effect for both being a transition from delocalized to localized states, and hence the loss of the signature electronic structure of graphene.

关键词： graphene functionalization chemical vapor deposition density functional theory