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991.
J. Fritz 《Journal of statistical physics》1979,20(4):351-369
The time evolution of an open system of infinitely many two-dimensional classical particles is investigated. Particles are interacting by a singular pair potentialU, and each particle is connected to a heat bath of temperatureT. The heat baths are represented by independent white noise forces and Langevin damping terms. Existence of strong solutions to the corresponding infinite system of stochastic differential equations is proved for initial configurations with a logarithmic order of energy fluctuations. Gibbs states forU at temperatureT are invariant under time evolution. 相似文献
992.
V. Solo 《Stochastic Processes and their Applications》1982,13(2):139-156
The aim here is to show how to obtain many of the well-known limit results (i.e., central limit theorem, law of the iterated logarithm, invariance principle) of stochastic approximation (SA) by a shorter argument and under weaker conditions. The idea is to introduce an artificial sequence, related to the SA scheme, and which clearly obeys the limit law. This sequence is subtracted from the SA scheme and then simple deterministic limit theory is used to show the remainder is negligible. As a consequence of this approach proofs are shorter and the meaning of conditions becomes clearer. Because the difference equations are not summed up it is simple to state results for general an, cn sequences. 相似文献
993.
Linear-quadratic two-person zero-sum differential games,necessary and sufficient conditions: Comment
P. Bernhard 《Journal of Optimization Theory and Applications》1980,31(2):283-284
We give a simpler, easier-to-check, version of the theorem of the paper referred to, i.e., a necessary and sufficient condition for the existence of a saddle point to the linear-quadratic two-person zero-sum perfect information differential game. 相似文献
994.
995.
996.
997.
Nazakat Ullah 《Pramana》1976,7(5):316-318
An exact differential equation is given to evaluate the energy average of the scattering function. The advantage of the differential
equation as compared to the earlier methods based on series expansion is that one has to evaluate only single sums over the
complex poles of the S-matrix. Using Wigner’s semicircle law for the distribution of the real parts of the poles of the scattering
matrix, the earlier expression for the energy average of the scattering function is rederived. 相似文献
998.
The nonlinear Boltzmann equation with a discretized spatial variable is studied in a Banach space of absolutely integrable functions of the velocity variables. Conservation laws and positivity are utilized to extend weak local solutions to a global solution. This is shown to be a strong solution by analytic semigroup techniques.Supported by National Science Foundation Grant ENG-7515882. 相似文献
999.
1000.
Li Li-qing Chen Dong-hua College of Chemistry Life Sciences South Central University for Nationalities Wuhan Hubei China 《武汉大学学报:自然科学英文版》2004,9(2):239-246
0 IntroductionThetechnologyofthermalanalysishasbeenwidelyusedinthestudyofthermalbehaviorandthermalcharacterofsolidstatereaction ,theprimaryintentionofthermalanalysiskineticsistoestablishseparatevaluesofapparentactivationenergyE ,themostprobablemechanism g(α)andthepre exponentialfactorA ,meanwhilethedeterminationofg(α)hasgraduallybeenthefocusofthisfield .Inthisfield ,therearemostlygeneralkineticsmethodsused presently ,suchasCoats Redfern’s[1 ] integralmethod ,Achar’s[2 \〗differentialmet… 相似文献