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901.
902.
903.
The literature about maximum of entropy for Markov processes deals mainly with discrete-time Markov chains. Very few papers dealing with continuous-time jump Markov processes exist and none dealing with semi-Markov processes. It is the aim of this paper to contribute to fill this lack. We recall the basics concerning entropy for Markov and semi-Markov processes and we study several problems to give an overview of the possible directions of use of maximum entropy in connection with these processes. Numeric illustrations are presented, in particular in application to reliability. 相似文献
904.
We present a detailed study of the first simple mechanical system that shows fully realistic transport behavior while still being exactly solvable at the level of equilibrium statistical mechanics. The system under consideration is a Lorentz gas with fixed freely-rotating circular scatterers interacting with point particles via perfectly rough collisions. Upon imposing a temperature and/or a chemical potential gradient, a stationary state is attained for which local thermal equilibrium holds for low values of the imposed gradients. Transport in this system is normal, in the sense that the transport coefficients which characterize the flow of heat and matter are finite in the thermodynamic limit. Moreover, the two flows are non-trivially coupled, satisfying Onsager's reciprocity relations to within numerical accuracy as well as the Green–Kubo relations. We further show numerically that an applied electric field causes the same currents as the corresponding chemical potential gradient in first order of the applied field. Puzzling discrepancies in higher order effects (Joule heating) are also observed. Finally, the role of entropy production in this purely Hamiltonian system is shortly discussed. 相似文献
905.
周焯华 《数学的实践与认识》2004,34(12):100-106
可计算一般均衡 (CGE)模型的参数估计或校准要求一个一致性的数据 ,而这个一致性的数据集则由社会核算矩阵 SAM(Social Accounting Matrix)所构成 .由于在许多国家特别是发展中国家 ,由于构成SAM的各种数据来源不同可能使这些来源不同的数据不一致 ,因此如何平衡和估计 SAM则是一个困难和关键的问题 .本文用交互熵方法如何建立和平衡 SAM. 相似文献
906.
本文提出了应用广义最大熵(Generalized Maximum Entropy,简称 GME)的方法对顾客满意度进行测评,该方法能够处理有限的或者不完全数据.采用了一个应用于美国顾客满意指数(ACSI)的简单模型生成仿真数据,比较GME和PLS两种方法的性能.仿真结果表明,与PLS方法相比,GME方法具有更高的拟合精度和较低的预测误差,在样本数据较少时,表现更为明显. 相似文献
907.
The collocation method based on quartic B‐spline interpolation is studied for numerical solution of the regularized long wave (RLW) equation. The time‐split RLW equation is also solved with the quartic B‐spline collocation method. Numerical accuracy is tested by obtaining the single solitary wave solution. Then, interaction, undulation and evolution of solitary waves are studied. Solutions are compared with available results. Conservation quantities are computed for all test experiments. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2007 相似文献
908.
通过一个简单的具体问题,对内能和机械能之间的本质区别进行了解析,这对于深入理解热力学中的概念及其规律的本质是极有意义的。 相似文献
909.
B. V. Lebedev K. B. Zhogova Ya. V. Denisova G. P. Belov O. N. Golodkov 《Russian Chemical Bulletin》1998,47(2):277-281
The temperature dependence of the heat capacity of the alternating copolymer (ACP) of carbon monoxide with ethylene was studied,
and temperatures and enthalpies of its phase transformations were measured by adiabatic vacuum, dynamic, and isothermal calorimetry
in the temperature range from 8 to 600 K. The energy of burning of ACP was measured at 298.15 K in a calorimeter with the
static bomb and isothermal shell. The thermodynamic parameters of transformation of the α-form of ACP crystals into the β-form
and fusion of the β-form were determined. The thermodynamic functions for the 0–507 K range and thermodynamic characteristics
atT=298.15 K andp=101.325 kPa were calculated. The thermodynamic parameters of the alternating copolymerization of ethylene and CO at 0–507
K and standard pressure were calculated for the bulk reaction.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 284–288, February, 1998. 相似文献
910.
本文定义并证明了Markov链的收敛性,在此基础上得到了与能耗系统“熵增加原理”相对应的Markov链信息系统熵增加定理. 相似文献