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271.
In this letter, a new auxiliary function method is presented for constructing exact travelling wave solutions of nonlinear partial differential equations. The main idea of this method is to take full advantage of the solutions of the elliptic equation to construct exact travelling wave solutions of nonlinear partial differential equations. More new exact travelling wave solutions are obtained for the generalized coupled Hirota–Satsuma KdV system. 相似文献
272.
In this paper, a theorem on the moderate deviation principle for random arrays under m-dependence with unbounded m is established. This partially extends the results of Chen (Stat. Probab. Lett. 35:123–134, 1997). As an application, the moderate deviation principle for the truncation estimator of the variance in the analysis of time
series is obtained.
相似文献
273.
The notions of exhausters were introduced in (Demyanov, Exhauster of a positively homogeneous function, Optimization 45, 13–29
(1999)). These dual tools (upper and lower exhausters) can be employed to describe optimality conditions and to find directions
of steepest ascent and descent for a very wide range of nonsmooth functions. What is also important, exhausters enjoy a very
good calculus (in the form of equalities). In the present paper we review the constrained and unconstrained optimality conditions
in terms of exhausters, introduce necessary and sufficient conditions for the Lipschitzivity and Quasidifferentiability, and
also present some new results on relationships between exhausters and other nonsmooth tools (such as the Clarke, Michel-Penot
and Fréchet subdifferentials). 相似文献
274.
The cyclic projections algorithm is an important method for determining a point in the intersection of a finite number of closed convex sets in a Hilbert space. That is, for determining a solution to the “convex feasibility” problem. This is the third paper in a series on a study of the rate of convergence for the cyclic projections algorithm. In the first of these papers, we showed that the rate could be described in terms of the “angles” between the convex sets involved. In the second, we showed that these angles often had a more tractable formulation in terms of the “norm” of the product of the (nonlinear) metric projections onto related convex sets.In this paper, we show that the rate of convergence of the cyclic projections algorithm is also intimately related to the “linear regularity property” of Bauschke and Borwein, the “normal property” of Jameson (as well as Bakan, Deutsch, and Li’s generalization of Jameson’s normal property), the “strong conical hull intersection property” of Deutsch, Li, and Ward, and the rate of convergence of iterated parallel projections. Such properties have already been shown to be important in various other contexts as well. 相似文献
275.
276.
刘自伟 《微电子学与计算机》2005,22(12):110-112
在传统主动数据库的基础上,提出了主动WEB_DB的概念,讨论了主动WEB_DB的体系结构、实现途径以及在客户关系管理系统中的应用。 相似文献
277.
改进802.1x认证技术的研究 总被引:2,自引:0,他引:2
文章介绍了802.1x协议的基本概念和原理,对802.1x协议在以太网安全认证管理中的实际应用进行了分析,指出了802.1x协议存在的漏洞。为解决权限管理、地址分配等方面存在的问题,提出了新的方法和实用的改进方案。 相似文献
278.
279.
全分布式位置管理策略的负载和位置更新性能研究 总被引:1,自引:1,他引:0
分布式位置管理策略及其分布式数据库结构与传统位置管理策略和HLR-VLR结构有显著区别,本文基于一种对DDB结构新的性能估计方法,从用户的移动性概率分布出发,对DDB结构下的数据库负载和位置更新性能进行了研究。 相似文献
280.
In this paper, a high-order iterative scheme is established in order to get a convergent sequence at a rate of order N(N?1) to a local unique weak solution of a nonlinear Kirchhoff-Carrier wave equation associated with mixed nonhomogeneous conditions - the boundary conditions are Dirichlet in one part and Robin in other part of boundary. On the other hand, some numerical results were presented. 相似文献