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On the fundamental equation of nonequilibrium statistical physics—Nonequilibrium entropy evolution equation and the formula for entropy production rate

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2194-2215页

作者： XING XiuSan Department of Physics, beijing Institute of Technology, beijing 100081, China 1. Department of Physics Beijing Institute of Technology Beijing 100081 China

In this paper the author presents an overview on his own research works. More than ten years ago, we proposed a new fundamental equation of nonequilibrium statistical physics in place of the present Liouville equation. That is the stochastic velocity type’s Langevin equation in 6N dimensional phase space or its equivalent Liouville diffusion equation. This equation is time-reversed asymmetrical. It shows that the form of motion of particles in statistical thermodynamic systems has the drift-diffusion duality, and the law of motion of statistical thermodynamics is expressed by a superposition of both the law of dynamics and the stochastic velocity and possesses both determinism and probability. Hence it is different from the law of motion of particles in dynamical systems. The stochastic diffusion motion of the particles is the microscopic origin of macroscopic irreversibility. Starting from this fundamental equation the BBGKY diffusion equation hierarchy, the Boltzmann collision diffusion equation, the hydrodynamic equations such as the mass drift-diffusion equation, the Navier-Stokes equation and the thermal conductivity equation have been derived and presented here. What is more important, we first constructed a nonlinear evolution equation of nonequilibrium entropy density in 6N, 6 and 3 dimensional phase space, predicted the existence of entropy diffusion. This entropy evolution equation plays a leading role in nonequilibrium entropy theory, it reveals that the time rate of change of nonequilibrium entropy density originates together from its drift, diffusion and production in space. From this evolution equation, we presented a formula for entropy production rate (i.e. the law of entropy increase) in 6N and 6 dimensional phase space, proved that internal attractive force in nonequilibrium system can result in entropy decrease while internal repulsive force leads to another entropy increase, and derived a common expression for this entropy decrease rate or anothe

关键词： stochastic velocity type’s Langevin equation in 6N dimensional phase space drift-diffusion duality nonequilibrium entropy evolution equation entropy diffusion formula for entropy production rate entropy change from internal interaction a

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Reliability analysis of M/G/1 queues with general retrial times and server breakdowns

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Progress in Natural Science:Materials International 2006年第5期16卷 464-473页

作者： WANG Jinting (Department of Mathematics, beijing Jiaotong University, beijing 100044, China) Department of Mathematics Beijing Jiaotong University Beijing 100044 China

This paper concerns the reliability issues as well as queueing analysis of M/G/1 retrial queues with general retrial times and server subject to breakdowns and repairs. We assume that the server is unreliable and customers who find the server busy or down are queued in the retrial orbit in accordance with a first-come-first-served discipline. Only the customer at the head of the orbit queue is allowed for access to the server. The necessary and sufficient condition for the system to be stable is given. Using a supplementary variable method, we obtain the Laplace-Stieltjes transform of the reliability function of the server and a steady state solution for both queueing and reliability measures of interest. Some main reliability indexes, such as the availability, failure frequency, and the reliability function of the server, are obtained.

关键词： retrial queues general retrial times reliability server breakdowns and repairs.

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Neighborhood-following algorithms for linear programming

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Science China Mathematics 2004年第6期47卷 812-820页

作者： Al WenbaoSchool of Science, beijing University of Posts and Telecommunications, beijing 100876, China 1. School of Science Beijing University of Posts and Telecommunications 100876 Beijing China

In this paper, we present neighborhood-following algorithms for linear programming. When the neighborhood is a wide neighborhood, our algorithms are wide neighborhood primal-dual interior point algorithms. If the neighborhood degenerates into the central path, our algorithms also degenerate into path-following algorithms. We prove that our algorithms maintain the O9√nL) -iteration complexity still, while the classical wide neighborhood primal-dual interior point algorithms have only the O(nL-iteration complexity. We also proved that the algorithms are quadratic convergence if the optimal vertex is nondegenerate. Finally, we show some computational results of our algorithms.

关键词： linear programming primal-dual interior point methods wide neighborhood methods quadratic convergence

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CABOSFV algorithm for high dimensional sparse data clustering

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Journal of University of Science and Technology beijing 2004年第3期11卷 283-288页

作者： Sen Wu Xuedong Gao Management School, University of Science and Technology beijing, beijing 100083, China Mgmt. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

An algorithm, Clustering Algorithm Based On Sparse Feature Vector (CABOSFV),was proposed for the high dimensional clustering of binary sparse data. This algorithm compressesthe data effectively by using a tool 'Sparse Feature Vector', thus reduces the data scaleenormously, and can get the clustering result with only one data scan. Both theoretical analysis andempirical tests showed that CABOSFV is of low computational complexity. The algorithm findsclusters in high dimensional large datasets efficiently and handles noise effectively.

关键词： clustering data mining sparse high dimensionality

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SELF-CONSISTENT TOTAL ENERGIES AND ELECTRONIC STRUCTURES OF HYDROGENIZED Ni,Al AND Ni_3Al

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Acta Metallurgica Sinica(English Letters) 1994年第3期7卷 220-228页

作者： XIE Qian, CHEN NanxianUniversity of Science and Technology beijing. beijing, China beijing Univ of Science and Technology Beijing China

By use of the self-consistent method of linear muffin-tin orbitals with the atomic sphere approximation on the basis of density functional theory, the total energies and the electron-ic sTructures ofNi, Al, and their hydrides NiH. A1H and Ni3AlH are calculated. The theoretical excess energies and the lattice strains due to hydrogen absorption consequently obtained from the ah initio results indicate that Ni is a better hydrogen absorber than Al, an. the absorptivity of Ni3Al dramatically decreases owing to the repulsion between Al and H On the other hand, the changes of band structures due to hydrogenation are found to be remparkable except that tor Al. and they are shown to be the qualitative manifestation of existing conclusions from photoemission experiments.

关键词： total energy electronic structure hydrogenized Ni. Ai. Ni3Al

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Chaotic attitude and reorientation maneuver for completely liquid-filled spacecraft with flexible appendage

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Acta Mechanica Sinica 2009年第2期25卷 271-277页

作者： B. Yue Department of Mechanics, School of Science,beijing Institute of Technology, 100081 beijing, China Department of Mechanics School of Science Beijing Institute of Technology 100081 Beijing China

The present paper investigates the chaotic attitude dynamics and reorientation maneuver for completely viscous liquid-filled spacecraft with flexible appendage. All of the equations of motion are derived by using Lagrangian mechanics and then transformed into a form consisting of an unperturbed part plus perturbed terms so that the system＇s nonlinear characteristics can be exploited in phase space. Emphases are laid on the chaotic attitude dynamics produced from certain sets of physical parameter values of the spacecraft when energy dissipation acts to derive the body from minor to major axis spin. Numerical solutions of these equations show that the attitude dynamics of liquid-filled flexible spacecraft possesses characteristics common to random, non- periodic solutions and chaos, and it is demonstrated that the desired reorientation maneuver is guaranteed by using a pair of thruster impulses. The control strategy for reorientation maneuver is designed and the numerical simulation results are presented for both the uncontrolled and controlled spins transition.

关键词： Nonlinear attitude dynamics Attitude reorientation maneuver Control strategyLiquid-filled spacecraft

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Synthesis and Structural Characterization of One-dimensional Polynuclear Complex [La(bipyN_2O_2)(TFA)_3]_n

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Chinese Chemical Letters 2000年第10期11卷 935-936页

作者： Wen Xiang ZHU, Yun HE (Department of Chemistry, beijing Normal University, beijing 100875) (Department of Pharmacy, beijing Staff Medical College, beijing 1.003.) Department of Chemistry Beijing Normal University Beijing 100875 China Department of Pharmacy Beijing Staff Medical College Beijing 100036 China

A novel polymeric complex [La(bipyN2O2)(TFA)3]n(TFA= trifluoroacetylacetone) was prepared. The X-ray structure analysis revealed that the complex has an infinite one-dimensional supramolecule structure with the 4,4'-bipyridyl-N,N'-dioxide as a bridge. La(III) is coordinated to eight oxygen atoms, six from three trifluoroacetylacetonate anions, two from two 4,4'-bipyridyl-N,N'-dioxide molecules.

关键词： Lanthanum polynuclear complex trifluoroacetylacetone 4,4'-bipyridyl-N,N'-dioxide.

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SINGLE BIRTH PROCESSES

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 77-82页

作者： CHEN MUFA(Department of Mathematics,beijing Normal University,beijing 100875,China) beijing Normal Univ Dept Math Beijing 100875 Peoples R China

The single birth process is a Markov chain, either time-continuous or time-discrete, valuedin the non-negative integers: the system jumps with positive rate from k to k + 1 but not tok +j for all j 2 (this explains the meaning of 'single birth') . However, there is no restrictionfor the jumps from k to k - j(1 j< k). This note mainly deals with the uniqueness problemfor the time-continuous processes with an extension: the jumps from k to k + 1 may also beforbidden for at most finite number of k. In both cases (time-continuous or -discrete), thehitting probability and the first moment of the hitting time are also studied

关键词： Markov chains Single birth process Uniqueness criterion

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Mathematical-Physical Modelling of Seismic Response of the beijing Depression

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Acta Geologica Sinica(English Edition) 1988年第2期1卷 141-158页

作者： Peng Yimin Sun Jinzhong Hao Xiansheng China University of Geoscience, beijing Central Research Institute of Building and Construction, Ministry of Metallurgical Industry, beijing China University of Geoscience Beijing China

There is a NE-trending earthquake hazard anomalous zone in the western part of the area of the city ofbeijing proper. A comprehensive study of it has been made. In the study the two-dimensional finite element dy-namic analysis and supersonic seismic model experiments were conducted for the first time. and some prelimi-nary results have been achieved. The beijing depression, a lower order tectonic unit in the beijing downwarp, is just located below theearthquake hazard anomalous zone. Analysis of the experimental results shows that the topography of the bu-ried bedrock is the main factor responsible for the presence of the anomalous zone. Besides. thetwo-dimensional mathematical analysis has more marked advantages in reflecting the lateral inhomogeneity ofthe foundation as compared with the one-dimensional one. and the supersonic seismic model experiments mayreflect the integrated effects of the earthquake sources, path of wave propagation and site geological structurein an all-round way.

关键词： mode In show

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Fractal Structure of the Core Loss Spectrum of Co-based Amorphous Soft Magnetic Alloy with Constant Permeability

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 54-56页

作者： Yiping Chen (Applied Science School, University of Science and Technology beijing, beijing 100083, China) Applied Science School University of Science and Technology Beijing Beijing 100083 China

In order to check the traditional core loss formula, the core loss spectrum P(f) of Co-based amorphous soft magnetic alloy with constant permeability has been studied. It is found that within a high frequency range from 10 kHz to 200 kHz and at Bm = 0. 1 T,the P(f) has the fractal structure P (f) = Po, and with the increasing of induced anisotropy energy Ku, the fractal dimension Dfrises, thus the total power loss at high frequency increases and the frequency characteristic of P(f) becomes worse.

关键词： amorphous soft magnetic alloy constant permeability core loss fractal

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