独立元件组成的n中取k系统剩余寿命的年龄性质

研究了独立元件组成的n中取k系统的剩余寿命长度的年龄性质,该系统在时刻t＜0有n-k个元件失效.对于几类寿命分布元件,讨论了元件仅仅独立的情形下,n中取k个系统剩余寿命的特征.     

平均样本间隔的性质及其在拍卖中的应用

研究了平均样本间隔E(Xk+1:n-Xk:n)的性质.证明了当X具有DRHR年龄性质时,E(Xk+1:n-Xk:n)关于样本容量n递减.而当X具有IFR年龄性质时,E(Xk+1:n-Xk:n)-E(Xk+2:n+1-Xk+1:n+1)非负.最后,讨论了主要结果在拍卖模型中的应用.     

Optimal replacement strategies for repairable systems

This paper considers repair-replacement models introduced by Lam Yeh [6] and [7], and Stadje and Zuckerman [9]. Without imposing reliability theory conditions on the repair and operating distributions, the optimal replacement problem is first solved in a finite horizon setting and then extensions are given to the infinite horizon case.     

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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.     

关于DMRL序及其相关序的若干性质

证明了DMRL偏序关系在平移和尺度变换下的不变性,并获得了一个充分必要条件.同时考虑了DMRL序与IFR及IFRA序之间的关系.     

A measure of discrimination between two residual life-time distributions and its applications

A measure of discrepancy between two residual-life distributions is proposed on the basis of Kullback-Leibler discrimination information. Properties of this measure are studied and the minimum discrimination principle is applied to obtain the proportional hazards model.Northern Illinois University on a professional development leave.     

A note on expected rent in auction theory

The expected rent in a reverse (buyer's) auction is shown to be monotonically nonincreasing in the number of bidders if the distribution of valuations is DRHR (IFR). Conditions under which an increase in the spread of bids results in an increase in the expected rent are established as well.     

随机时间剩余寿命的分布类性质

得出了随机时间剩余寿命XY的随机比较性质和矩不等式．当Y是指数分布时求出了XY的故障率的界．     

Stochastic Comparison of Age-Dependent Block Replacement Policies

The age-dependent block replacement policy is a modified block replacement policy with an age limit for preventive replacements. Under this policy, any failed component is repaired, but only the components whose ages exceed a fixed age limit are replaced preventively at the scheduled maintenance times. Using the compensator method, we compare stochastically the failure counting processes of the age-dependent block replacement policies with different parameters, and show that the age-dependent block replacement policy, although cost effective, leads to more failures than the age and block replacement policies. AMS 2000 Subject Classification 60K10