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31.
在II型双截尾删失计划下,讨论了当系统被独立的随机施加指数Pareto (EP)压力时的系统可靠性问题.作者给出了系统可靠性参数的不同点估计和区间估计,其中点估计包括一致最小方差无偏估计(UMVUE)和最大似然估计(MLE);区间估计包括精确置信区间,近似置信区间和bootstrap的区间估计.为了评价不同估计方法效果,作者提供数值模拟结果;最后提供了一个真实数据的分析结果来演示本文提出的方法. 相似文献
32.
Heyman gives an interesting factorization of I-P, where P is the transition probability matrix for an ergodic Markov chain. We show that this factorization is valid if and only if
the Markov chain is recurrent. Moreover, we provide a decomposition result which includes all ergodic, null recurrent as well
as the transient Markov chains as special cases. Such a decomposition has been shown to be useful in the analysis of queues.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
33.
We consider a doubly nonlocal nonlinear parabolic equation which describes phase-segregation of a two-component material in a bounded domain. This model is a more general version than the recent nonlocal Cahn–Hilliard equation proposed by Giacomin and Lebowitz [26], such that it reduces to the latter under certain conditions. We establish well-posedness results along with regularity and long-time results in the case when the interaction between the two levels of nonlocality is strong-to-weak. 相似文献
34.
Qian Lin 《数学学报(英文版)》2010,26(8):1525-1534
In this paper, we deal with a class of one-dimensional backward doubly stochastic differential equations (BDSDEs). We obtain a generalized comparison theorem and a generalized existence theorem of BDSDEs. 相似文献
35.
36.
In this paper, we study one-dimensional reflected backward doubly stochastic differential equations (RBDSDEs) with one continuous barrier and discontinuous (left or right continuous) generator. We obtain an existence theorem and a comparison theorem for solutions of the class of RBDSDEs. 相似文献
37.
Wei-jun Lu 《高校应用数学学报(英文版)》2013,28(2):240-252
In this paper, we study f-harmonicity of some special maps from or into a doubly warped product manifold. First we recall some properties of doubly twisted product manifolds. After showing that the inclusion maps from Riemannian manifolds M and N into the doubly warped product manifold M × μ,λ N can not be proper f-harmonic maps, we use projection maps and product maps to construct nontrivial f-harmonic maps. Thus we obtain some similar results given in [21], such as the conditions for f-harmonicity of projection maps and some characterizations for non-trivial f-harmonicity of the special product maps. Furthermore, we investigate non-trivial f-harmonicity of the product of two harmonic maps. 相似文献
38.
Richard A. Brualdi 《Linear and Multilinear Algebra》2013,61(3):393-408
We consider a class of matrices whose row and column sum vectors are majorized by given vectors b and c, and whose entries lie in the interval [0,?1]. This class generalizes the class of doubly stochastic matrices. We investigate the corresponding polytope Ω(b|c) of such matrices. Main results include a generalization of the Birkhoff–von Neumann theorem and a characterization of the faces, including edges, of Ω(b|c). 相似文献
39.
40.
依据最弱受约束电子势模型及其微扰修正理论,计算了铍原子1s22pnd 1Po1 (n=3-50)双激发态系列能级和量子亏损。计算结果与已有的实验结果符合得很好。 相似文献