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71.
本文提出的热爆炸临界参数的数值解法是一种变分方法.这种方法依据的是文献[1]给出的热爆炸临界参数的一个变分原理。数值计算的结果表明,这种方法是一种简便、经济而又精确度较高的方法。 相似文献
72.
We propose a simple game whose solution contains a singular focal line, i.e., a focal line reached by optimal trajectories in a nontangential fashion. We also provide a discussion of how the optimal discriminating strategy can be approximated by a pure feedback.This work was prepared while the first author was visiting at INRIA-Sophia Antipolis, Valbonne, France. 相似文献
73.
A class of service stage Petri net models whose equilibrium probabilities satisfy local balance equations is presented. Examples of their applicability include bus oriented multiprocessor interconnections, the classical dining philosophers problem and the alternating bit protocol. The natural topological space for embedding the state transition lattice for this class of SSPN is shown to be a multidimensional toroidal manifold. 相似文献
74.
Solution differentiability for variational inequalities 总被引:1,自引:0,他引:1
Jerzy Kyparisis 《Mathematical Programming》1990,48(1-3):285-301
In this paper we study solution differentiability properties for variational inequalities. We characterize Fréchet differentiability of perturbed solutions to parametric variational inequality problems defined on polyhedral sets. Our result extends the recent result of Pang and it directly specializes to nonlinear complementarity problems, variational inequality problems defined on perturbed sets and to nonlinear programming problems. 相似文献
75.
This paper investigates the existence of positive solutions of a singular boundary value problem with negative exponent similar
to standard Emden-Fowler equation. A necessary and sufficient condition for the existence of C[0, 1] positive solutions as
well as C1[0, 1] positive solutions is given by means of the method of lower and upper solutions with the Schauder fixed point theorem. 相似文献
76.
We study the system of nonlinear differential equations which expresses the constancy of the algebraic invariants of the Jacobian matrix for smooth vector fields in three-dimensional space. This system is equivalent to the equations of gas dynamics which describe the barochronous motions of a gas (the pressure and density depend only on the time). We present the results of computation of the admissible local Lie group and construction of the general solution of the system. We mention a few new problems that arise here. 相似文献
77.
We construct a fundamental solution for a parabolic equation with drift on a Riemannian manifold of nonpositive curvature. We obtain some estimates for this fundamental solution that depend on the conditions on the drift field. 相似文献
78.
Given a closed convex set K in Rn; a vector function F:K×K Rm; a closed convex (not necessarily pointed) cone P(x) in m with non-empty interior, PP(x) Ø, various existence results to the problemfind xK such that F(x,y)- int P(x) y K
under P(x)-convexity/lower semicontinuity of F(x,) and pseudomonotonicity on F, are established. Moreover, under a stronger pseudomonotonicity assumption on F (which reduces to the previous one in case m=1), some characterizations of the non-emptiness of the solution set are given. Also, several alternative necessary and/or sufficient conditions for the solution set to be non-empty and compact are presented. However, the solution set fails to be convex in general. A sufficient condition to the solution set to be a singleton is also stated. The classical case P(x)=m
+ is specially discussed by assuming semi-strict quasiconvexity. The results are then applied to vector variational inequalities and minimization problems. Our approach is based upon the computing of certain cones containing particular recession directions of K and F. 相似文献
79.
We study a GI/M/c type queueing system with vacations in which all servers take vacations together when the system becomes empty. These servers keep taking synchronous vacations until they find waiting customers in the system at a vacation completion instant.The vacation time is a phase-type (PH) distributed random variable. Using embedded Markov chain modeling and the matrix geometric solution methods, we obtain explicit expressions for the stationary probability distributions of the queue length at arrivals and the waiting time. To compare the vacation model with the classical GI/M/c queue without vacations, we prove conditional stochastic decomposition properties for the queue length and the waiting time when all servers are busy. Our model is a generalization of several previous studies. 相似文献
80.
Oleg Palumbíny 《Czechoslovak Mathematical Journal》2003,53(2):467-477
The paper deals with oscillation criteria of fourth order linear differential equations with quasi-derivatives. 相似文献