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71.
A sojourn time analysis is provided for a cyclic-service tandem queue with general decrementing service which operates as follows: starting once a service of queue 1 in the first stage, a single server continues serving messages in queue 1 until either queue 1 becomes empty, or the number of messages decreases to k less than that found upon the server's last arrival at queue 1, whichever occurs first, where 1 ≤ k ≤ ∞. After service completion in queue 1, the server switches over to queue 2 in the second stage and serves all messages in queue 2 until it becomes empty. It is assumed that an arrival stream is Poissonian, message service times at each stage are generally distributed and switch-over times are zero. This paper analyzes joint queue-length distributions and message sojourn time distributions. 相似文献
72.
赵晓强 《应用数学学报(英文版)》1995,11(3):263-267
ONTHEEXISTENCEOFGLOBALGENERALSOLUTIONSOF POLYNOMIALSYSTEMSZHAOXIAOQIANG(赵晓强)(InstituteofAppliedMathematics,theChineseAcademyo... 相似文献
73.
A general solution of the three-dimensional equilibrium problem of spherically isotropic magnetoelectroelastic media is presented. Base on the obtained general solution, exact and compact form solutions are obtained for (1) a spherically isotropic magnetoelectroelastic cone subjected to concentrated force, concentrated couple, a point charge and a point electric current at its apex; (2) a spherically isotropic magnetoelectroelastic space with a concentrated force at the origin; (3) a spherical shell under spherically symmetric deformation; and (4) stress concentration around a spherical cavity subjected to remote uniform tensile force, electric charge and electric current. 相似文献
74.
1.引言数值方法的动力特征近年引起了人们的广泛关注。其中之一就是系统的平衡态和数值方法的平衡态相一致的问题,即用一个数值方法沿定步长求解系统时,是否会出现伪平衡。不可能出现伪平衡的方法称为是正则的。RK方法和线性多步法的正则性已被众多的文献研究[2,3,4],其它方法的正则性显然是一亟待研究的问题。本文讨论较RK方法和线性多步法远为广泛的一般线性方法的正则性。设f:R~(N)→R~(N)是一充分光滑的映射,考虑求解初值问题:的一般线性方法[1]:其中步长逼近于逼近于关于微分方程真解y(t)在第n层… 相似文献
75.
HILBERT空间中散逸动力系统一般线性方法的散逸稳定性 总被引:9,自引:0,他引:9
1.引言 1994年,Stuart与 Humphries[4,5]首先考察了用 Runge-Kutta方法求解 Rm中的散逸动力系统(2.1)-(2.2)时数值解是否继承真解具有的散逸稳定性,并表明代数稳定且不可约的 Runge-Kutta方法是散逸稳定的且有一有界吸引集.1996年,本文作者[1]把这一工作推广到了两类特殊的一般线性方法.1997年,Hill在[3]中证明了A-稳定是单支方法散逸稳定的充要条件,在[2]中又把文[4,5]的工作推广到了 Hilbert空间中的散逸动力系统(2.1)-(… 相似文献
76.
Jean-Franois Renaud 《Insurance: Mathematics and Economics》2009,45(2):242-246
We study the distribution of tax payments in the model of Kyprianou and Zhou [Kyprianou, A.E., Zhou, X., 2009. General tax structures and the Lévy insurance risk model. J. Appl. Probab. (in press)], that is a Lévy insurance risk model with a surplus-dependent tax rate. More precisely, after a short discussion on the so-called tax identity, we derive a recursive formula for arbitrary moments of the discounted tax payments until ruin and we identify the distribution of the tax payments when there is no force of interest. 相似文献
77.
Yutsis graphs are connected simple graphs which can be partitioned into two vertex-induced trees. Cubic Yutsis graphs were introduced by Jaeger as cubic dual Hamiltonian graphs, and these are our main focus.Cubic Yutsis graphs also appear in the context of the quantum theory of angular momenta, where they are used to generate summation formulae for general recoupling coefficients. Large Yutsis graphs are of interest for benchmarking algorithms which generate these formulae.In an earlier paper we showed that the decision problem of whether a given cubic graph is Yutsis is NP-complete. We also described a heuristic that was tested on graphs with up to 300,000 vertices and found Yutsis decompositions for all large Yutsis graphs very quickly.In contrast, no fast technique was known by which a significant fraction of bridgeless non-Yutsis cubic graphs could be shown to be non-Yutsis. One of the contributions of this article is to describe some structural impediments to Yutsisness. We also provide experimental evidence that almost all non-Yutsis cubic graphs can be rapidly shown to be non-Yutsis by applying a heuristic based on some of these criteria. Combined with the algorithm described in the earlier paper this gives an algorithm that, according to experimental evidence, runs efficiently on practically every large random cubic graph and can decide on whether the graph is Yutsis or not.The second contribution of this article is a set of construction techniques for non-Yutsis graphs implying, for example, the existence of 3-connected non-Yutsis cubic graphs of arbitrary girth and with few non-trivial 3-cuts. 相似文献
78.
In this article, some generalized multi-valued variational-like inequality problems and their related general auxiliary problems in real reflexive Banach spaces are introduced. An existence theorem for one of the general auxiliary problems is proved. Furthermore, by exploiting this theorem, an algorithm for the corresponding generalized multi-valued variational-like inequality problem is constructed. The theorems of this article generalize, improve and unify many known corresponding results. 相似文献
79.
Moshe Jarden 《代数通讯》2013,41(4):1467-1494
In this paper we establish several equivalent conditions for a commutative ring in which every principal ideal is a finite intersection of prime power ideals to be a general ZPI-ring. Using these results, we establish some equivalent conditions for a commutative ring in which every principal ideal is a finite intersection of primary ideals to be a general ZPI-ring. 相似文献
80.