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排序方式: 共有1177条查询结果,搜索用时 15 毫秒
61.
研究了一类具S-型分布时滞的模糊细胞神经网络(FCNN)的周期解及全局指数稳定性问题.在不要求激励函数全局L ipsch itz条件下,通过使用指数型二分性和Schauder不动点定理以及构造Lyapunov函数,得到了模糊细胞神经网络模型周期解和指数稳定性的一些充分条件.此外,给出一个实例说明结果是可行的. 相似文献
62.
Alexander R. Pruss 《Stochastic Processes and their Applications》1997,70(2):1547-180
Let X1, X2, … be independent identically distributed random variables. Then, Hsu and Robbins (1947) together with Erdös (1949, 1950) have proved that ,,
if and only if E[X21] < ∞ and E[X1] = 0. We prove that there are absolute constants C1, C2 (0, ∞) such that if X1, X2, … are independent identically distributed mean zero random variables, then
c1λ−2 E[X12·1{|X1|λ}]S(λ)C2λ−2 E[X12·1{|X1|λ}]
for every λ > 0. 相似文献
63.
Loskutov A. Yu. Prokhorov A. K. Rybalko S. D. 《Theoretical and Mathematical Physics》2002,132(1):983-999
A new effective local analysis method is elaborated for coupled map dynamics. In contrast to the previously suggested methods, it allows visually investigating the evolution of synchronization and complex-behavior domains for a distributed medium described by a set of maps. The efficiency of the method is demonstrated with examples of ring and flow models of diffusively coupled quadratic maps. An analysis of a ring chain in the presence of space defects reveals some new global-behavior phenomena. 相似文献
64.
M. Hosseinpour P. Nikdel M.A. Akbari 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):250-262
This article proposes a Takagi–Sugeno (T-S) fuzzy model of single-link rotary flexible joint robot. The proposed control method is based on parallel distributed control. The parameters of T-S controller are improved by distributed population genetic algorithm (GA) with chaos GA. Using Hermite–Biehler theorem in distributed population, GA is made to have a fast convergence. Dividing search space into several sub-spaces causes a better response, and chaos disturbance helps the whole algorithm to reach a best answer. The stability of the controller is analysed via the sum of squares programming, and finally, it is implemented on the plant. 相似文献
65.
Hans van den Berg Michel Mandjes Rudesindo Núñez-Queija 《Operations Research Letters》2007,35(3):297-307
We study a processor-sharing model in which users choose between a high- and a low-priority service, based on their utility functions and prices charged by the service provider. The latter aims at revenue maximization. The model is motivated by file transmissions in data networks with distributed congestion control. 相似文献
66.
LIN Wen-xian 《数学季刊》2005,20(4):418-422
In this paper, the sufficient conditions for the oscillation of all solutions of certain second order nonlinea neutral equations with continuous distributed delay. 相似文献
67.
现代哈萨克语词级标注语料库的构建研究 总被引:2,自引:0,他引:2
建设高质量的标注语料库是现代哈萨克语自然语言信息处理领域的基础性工程,本文根据哈萨克语独特的语言特点,进行词级带标注的哈萨克语语料库构建研究,首先介绍了不同语言语料库的国内外研究现状,随后针对语料库构建中涉及的主要问题,实现了哈萨克语词级基本语料库的设计与构建. 相似文献
68.
We propose a domain embedding method to solve second order elliptic problems in arbitrary two-dimensional domains. The method is based on formulating the problem as an optimal distributed control problem inside a disc in which the arbitrary domain is embedded. The optimal distributed control problem inside the disc is solved rapidly using a fast algorithm developed by Daripa et al. [3,7,10–12]. The arbitrary domains can be simply or multiply connected and the proposed method can be applied, in principle, to a large number of elliptic problems. Numerical results obtained for Dirichlet problems associated with the Poisson equation in simply and multiply connected domains are presented. The computed solutions are found to be in good agreement with the exact solutions with moderate number of grid points in the domain. 相似文献
69.
A. A. Borovkov 《Siberian Mathematical Journal》2005,46(6):1020-1038
Let ξ1,ξ2,... be independent random variables with distributions F1F2,... in a triangular array scheme (F i may depend on some parameter). Assume that Eξ i = 0, Eξ i 2 < ∞, and put \(S_n = \sum {_{i = 1}^n \;} \xi _i ,\;\overline S _n = \max _{k \leqslant n} S_k\). Assuming further that some regularly varying functions majorize or minorize the “averaged” distribution \(F = \frac{1}{n}\sum {_{i = 1}^n F_i }\), we find upper and lower bounds for the probabilities P(S n > x) and \(P(\bar S_n > x)\). We also study the asymptotics of these probabilities and of the probabilities that a trajectory {S k } crosses the remote boundary {g(k)}; that is, the asymptotics of P(maxk≤n(S k ? g(k)) > 0). The case n = ∞ is not excluded. We also estimate the distribution of the first crossing time. 相似文献
70.