失效单调关联系统的条件存活元件数量

单调关联系统在可靠性,生存分析和其他生命科学中扮演着非常重要的角色.在本文中,我们考虑了n中取(n-k+1)系统中存活元件的数量,假设在时刻t时存活的元件至少有(n-m+1)个,且系统在时刻t处于失效状态.在此条件下,我们计算系统中存活元件数量为i(i=n-m+1,…,n-k)的概率,从而获得了其可靠性与几个随机性质.此外,我们将结果扩展到具有绝对连续可交换元件的一般单调关联系统.     

单调关联系统的条件失效元件数量

Coherent systems are very important in reliability,survival analysis and other life sciences.In this paper,we consider the number of failed components in an(n-k+1)-out-of-n system,given that at least m(m相似文献   

一类不同可靠度部件非单调关联系统的最优设计

本文对航天系统中应用广泛的一类典型的非单调关联系统（ｎ中取ｒ至ｓ系统）进行了可靠性分析,比较了目前对系统进行可靠度计算的几种方法的优劣,详细研究了给定ｒ,ｓ及不同部件可靠度ｐ_ｉ的情况下,使系统效益达到最高的条件ｎ值的最优配置问题,并结合国外某类航天系统工程中的计算机集成系统给出了一个数值例子,并用面向 Ｗｉｎｄｏｗｓ的 ＶＢ６． ０实现了一个图形交互的求解系统最优配置和系统可靠度的软件．     

多状态可靠性系统动态signature及其剩余寿命分析

系统signature是分析系统可靠性的一个强有力的工具。本文研究了多状态系统的动态signature。Signature概念被拓展到多维的情形,并将其应用于两状态元件下多态关联系统的分析,得到系统在每一状态下的联合生存函数的表达式,探究了系统在时刻的动态signature,为处于工作状态的多状态系统在时刻t接受检查,发现其处于l(t)状态并且恰好已发生了q(t)次元件失效,分别给出了两状态元件多态关联系统动态signature及其剩余寿命的表达式。     

基于随机滤波法的滚动轴承剩余寿命预测

使用剩余寿命描述滚动轴承的潜在状态,基于随机滤波方法建立滚动轴承的剩余寿命预测模型,给出了建模步骤和方法,并讨论了模型的参数估计问题.实例分析结果验证了该建模方法和参数估计方法的有效性和准确性.     

一类并联系统的剩余寿命和平均剩余寿命

研究了n个独立但不同分布的元件构成的一类并联系统的剩余寿命和平均剩余寿命,即在t_1时刻有l个元件失效,第k个元件的寿命恰好是t_2(0≤lkn,0≤t_1t_2),系统在t_2时刻仍然工作的条件下并联系统的可靠性函数和平均剩余寿命.     

离散时间下马氏可修系统剩余寿命的极限分布

本文对离散马氏可修系统剩余寿命的极限分布进行了研究，指出此分布为几何分布，同时，对一些特殊的马氏可修系统给出其极限分布的参数，并给出了算例。     

基于分散型和扩散型随机序对几种寿命分布类的刻画

本文基于分散型和(或)扩散型随机序，利用随机变量的剩余寿命给出了寿命分布类ILR，IFR，DMRL和IFR(2)及其对偶类的刻画．作为主要结果的一个应用，用k／n-系统的剩余寿命对IFR和DMRLS及其对偶类进行了刻画．这些结果拓宽和加强了文献中已有的结果．     

一类混合单调算子的不动点定理

运用锥理论与迭代方法,讨论了在较弱条件下一类混合单调算子的不动点的存在唯一性,所得结果是某些已有结果的本质改进和推广.     

半序度量空间中单调映射的不动点定理及混合单调映射的耦合不动点定理

本文在度量空间中引入半序,证明了半序度量空间中单调增加映射的不动点定理及混合单调映射的耦合不动点定理．     

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??Coherent systems are very important in reliability,survival analysis and other life sciences. In this paper, we consider the number of working components in an $(n-k+1)$-out-of-$n$ system, given that at least $(n-m+1)$ components are working at time $t$, and the system has failed at time $t$. In this condition, we compute the probability that there are exactly $i$ working components. First the reliability and several stochastic properties are obtained. Furthermore, we extend the results to general coherent systems with absolutely continuous and exchangeable components.     

Mixture representation for the residual lifetime of a repairable system

In this paper, we consider a repairable system in which two types of failures can occur on each failure. One is a minor failure that can be corrected with minimal repair, whereas the other type is a catastrophic failure that destroys the system. The total number of failures until the catastrophic failure is a positive random variable with a given probability vector. It is assumed that there is some partial information about the failure status of the system, and then various properties of the conditional probability of the system failure are studied. Mixture representations of the reliability function for the system in terms of the reliability function of the residual lifetimes of record values are obtained. Some stochastic properties of the conditional probabilities and the residual lifetimes of two systems are finally discussed. Copyright © 2017 John Wiley & Sons, Ltd.     

排队系统平稳等待时间的性质

讨论了M/G/1排队系统平稳等待时间的随机序关系及利用Mathematica 4.0软件探讨了爱尔朗排队系统Er/M/1（r≤6）的平稳等待时间的分布。     

Stochastic Comparisons and Dependence among Concomitants of Order Statistics

Let (X_i, Y_i) i=1, 2, …, n be n independent and identically distributed random variables from some continuous bivariate distribution. If X_(r) denotes the rth ordered X-variate then the Y-variate, Y_[r], paired with X_(r) is called the concomitant of the rth order statistic. In this paper we obtain new general results on stochastic comparisons and dependence among concomitants of order statistics under different types of dependence between the parent random variables X and Y. The results obtained apply to any distribution with monotone dependence between X and Y. In particular, when X and Y are likelihood ratio dependent, it is shown that the successive concomitants of order statistics are increasing according to likelihood ratio ordering and they are TP₂ dependent in pairs. If we assume that the conditional hazard rate of Y given X=x is decreasing in x, then the concomitants are increasing according to hazard rate ordering and are dependent according to the right corner set increasing property. Finally, it is proved that if Y is stochastically increasing in X, then the concomitants of order statistics are stochastically increasing and are associated. Analogous results are obtained when the variables X and Y are negatively dependent. We also prove that if the hazard rate of the conditional distribution of Y given X=x is decreasing in x and y, then the concomitants have DFR (decreasing failure rate) distributions and are ordered according to dispersive ordering.     

不确定性对混合CVaR约束库存系统的影响

运用应用概率中的随机占优研究需求不确定性对混合CVaR约束库存系统最优订购量和最优利润的影响。引入刻画决策者风险态度的“风险偏好系数”,得到系统最优订购量和最优利润关于风险偏好系数的单调性。研究表明随机大需求总会导致系统较高的最优订购量和最优利润;在割准则序意义下,最优订购量可能随需求可变性的增加而增加也可能随需求可变性的增加而减少;在二阶随机占优且风险偏好系数大于等于1的情况下系统最优利润具有随机单调性,然而当风险偏好系数小于1时最优利润在二阶随机占优意义下的结论不一定成立,我们通过一个数值例子来说明。     

多值微分系统及动态规划中的泛函方程的可解性

本文利用不动点定理获得了完备距离空间中多值微分方程的非线性过值问题的解的存在性定理,同时给出了动态规划中的一类泛函方程的解存在性的充分条件。     

Representing the mean residual life in terms of the failure rate

In survival or reliability studies, the mean residual life or life expectancy is an important characteristic of the model. Whereas the failure rate can be expressed quite simply in terms of the mean residual life and its derivative, the inverse problem—namely that of expressing the mean residual life in terms of the failure rate—typically involves an integral of a complicated expression. In this paper, we obtain simple expressions for the mean residual life in terms of the failure rate for certain classes of distributions which subsume many of the standard cases. Several results in the literature can be obtained using our approach. Additionally, we develop an expansion for the mean residual life in terms of Gaussian probability functions for a broad class of ultimately increasing failure rate distributions. Some examples are provided to illustrate the procedure.     

Relationships between pure tail orderings of lifetime distributions and some concepts of residual life

The concepts of pure-tail orderings as defined by sq- and D-orderings are shown to order the family of reliability life distributions which age smoothly in a natural way. This ordering extends to comparisons regarding the limiting behavior of the residual life, mean residual life, sojourn time between perfect repairs in repairable systems, failure rate and, through the preservation of sq- and D-orderings by various reliability operations, to certain coherent systems of components that age smoothly. Possible applications of the results to the industrial practice of cannibalization are also noted.