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1.
讨论了一个由两个部件和一个储备部件并且具有临界人为错误和常规故障的随机模型,故障系统修复时间是任意分布的.运用泛函分析的方法,通过分析系统主算子谱特征,给出了系统稳定性的证明.  相似文献   

2.
讨论了一个由于常规原因和人为错误引起故障的两不同部件并行系统的模型,修复后的故障系统恢复正常.在假设修复率非常数的前提下,运用纯分析的方法给出了两不同部件并行系统解的性质,绕过了该系统解是否存在的问题.  相似文献   

3.
针对线性连续k-out-of-n:F系统提出定期检测策略,每隔固定周期对系统中各部件状态进行检查并以新部件更换故障部件,若系统发生故障则立即停机并更换故障部件.由于受到负载共享的影响,各工作部件故障率不仅与系统中发生故障的部件数量相关,还与其相邻部件状态有关;为此,引入损伤故障率模型描述部件故障率.基于故障序列图和更新报酬理论建立定期检测策略优化模型以最小化单位时间内的期望成本,确定最优检测周期.最后,通过算例分析验证模型的有效性.  相似文献   

4.
研究由两个部件串联组成的系统的预防维修策略,当系统的工作时间达到T时进行预防维修,预防维修使部件恢复到上一次故障维修后的状态.当部件发生故障后进行故障维修,因为各种原因可能会延迟修理.部件在每次故障维修后的工作时间形成随机递减的几何过程,且每次故障后的维修时间形成随机递增的几何过程.以部件进行预防维修的间隔T和更换前的故障次数N组成的二维策略(T,N)为策略,利用更新过程和几何过程理论求出了系统经长期运行单位时间内期望费用的表达式,并给出了具体例子和数值分析.  相似文献   

5.
讨论冷贮备可修系统与单部件可修系统在可靠性指标方面的关系,具有理论价值和实际意义.首先讨论由两部件组成的冷贮备可修系统与单部件可修系统的关系,假设冷贮备可修系统的每个部件的工作寿命都服从一般分布,部件故障后的修理时间服从指数分布,得到在稳态可用度、稳态故障频度、瞬时可用度和瞬时故障频度等指标方面冷贮备可修系统等价于相应的单部件可修系统,推导了若干个定理和推论,给出了相应结论;然后探讨带有冷贮备的多部件串联系统在求解可靠性指标时转化为相应单部件系统的思路:将带有一个冷贮备的多部件串联可修系统等价为一般的串联系统,进一步等价单部件可修系统.为工程上广泛存在的带有冷贮备的多部件系统的可靠性指标计算提供基础及相应公式.  相似文献   

6.
考虑两同型部件组成的并联可修系统,每个部件有两类故障状态,部件故障后修理有延迟,且修理设备在修理故障部件的过程中也可能发生故障.假定部件的寿命和修理设备的寿命服从指数分布,部件发生故障后的修理延迟时间、修理时间和修理设备故障后的更换时间均服从一般分布,利用马尔可夫更新过程理论和拉普拉斯变换工具,求得了系统有关的可靠性指标.  相似文献   

7.
讨论了两个部件并联和一个储备部件,并且具有临界认为错误和故障的可修系统稳态解中p_0的最优控制问题.  相似文献   

8.
研究了由两个运行部件和一个储备部件并且具有常规故障和临界人为错误的随机模型,故障系统的修复时间是任意分布的.先把系统方程的解转化为Volterra 积分方程的形式,证明了系统方程中正解的存在唯一性,再以泛数指标泛函作为衡量系统可控性的标准,研究该系统的最优控制问题.  相似文献   

9.
研究了两个不同型部件串联带有一个冷贮备部件的可修型冷贮备系统.假定三个部件的工作时间和维修时间均服从指数分布,对部件2的修理是几何维修而对部件1和3的修理则是修复如新,且部件2比部件3有优先使用权和优先维修权.在这些假设下,运用补充变量法与几何过程理论,得出了系统可靠度,首次故障前平均时间,可用度,瞬时故障频度和修理工空闲的概率等可靠性指标.  相似文献   

10.
泊松冲击下冷贮备可修系统的可靠性分析   总被引:1,自引:0,他引:1  
本文研究了一类由有限个同质部件和一个修理工组成的冷贮备可修系统在随机冲击下的可靠性问题。假设冲击以泊松过程到达。当冲击到达时,它会独立地对系统中工作的部件产生影响,而不会对冷贮备部件产生影响。每次冲击的量都服从某一确定的分布,受冲击的部件以一定的概率发生故障,其故障概率是冲击量的函数,当工作的部件发生故障时,下一个冷贮备部件立即开始工作,当所有部件故障时,系统故障,故障部件按故障顺序进行修理,修理时间服从指数分布,故障部件能被修理如新。本文显式给出了系统首次故障前平均时间、稳态可用度、稳态故障频度等可靠性指标。  相似文献   

11.
Redundancy or standby is a technique that has been widely applied to improving system reliability and availability in system design. In this paper, a general method for modelling standby system is proposed and system performance measures are derived. It is shown that the proposed general standby system includes the cases of cold, hot and warm standby systems with units of exponential distribution, which were studied in the literature, as special cases. An optimal allocation problem for a standby system is also discussed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

12.
It is well recognized that using the hot standby redundancy provides fast restoration in the case of failures. However the redundant elements are exposed to working stresses before they are used, which reduces the overall system reliability. Moreover, the cost of maintaining the hot redundant elements in the operational state is usually much greater than the cost of keeping them in the cold standby mode. Therefore, there exists a tradeoff between the cost of losses associated with the restoration delays and the operation cost of standby elements. Such a trade-off can be obtained by designing both hot and cold redundancy types into the same system. Thus a new optimization problem arises for the standby system design. The problem, referred to in this work as optimal standby element distributing and sequencing problem (SE-DSP) is to distribute a fixed set of elements between cold and hot standby groups and select the element initiation sequence so as to minimize the expected mission operation cost of the system while providing a desired level of system reliability. This paper first formulates and solves the SE-DSP problem for 1-out-of-N: G heterogeneous non-repairable standby systems. A numerical method is proposed for evaluating the system reliability and expected mission cost simultaneously. This method is based on discrete approximation of time-to-failure distributions of the system elements. A genetic algorithm is used as an optimization tool for solving the formulated optimization problem. Examples are given to illustrate the considered problem and the proposed solution methodology.  相似文献   

13.
Two-unit warm standby redundant systems have been investigated extensively in the past. The most general model is the one in which both the lifetime and repair time distributions of the units are arbitrary. However the study of standby systems with more than two units, though very important, has received much less attention, possibly because of the built-in difficulties in analyzing them. Such systems have been studied only when either the lifetime or the repair time is exponentially distributed. When both these distributions are general, the problem appears to be intractable even in the case of cold standby systems. The present contribution is an improvement in the state of art in the sense that a three unit warm standby system is shown to be capable of comprehensive analysis. In particular we show that there are imbedded renewal points that render the analysis possible. Using these imbedded renewal points we obtain the reliability and availability functions. Emeritus Deceased 23rd December 2003.  相似文献   

14.
研究的是泊松冲击下由三同型部件组成的单部件混合贮备系统可靠性.在系统三部件分别为工作部件、温贮备部件和冷贮备部件假定下,且假定三部件在工作过程中都是接着工作、修理、冷贮备、温贮备、工作依次进行状态转移,同时假设部件寿命和维修时间都服从指数分布,利用基本概率理论和马尔可夫过程理论分别对不可修和可修两类系统进行讨论得到相关可靠性指标.  相似文献   

15.
为了讨论由n个同型部件和一个转换开关组成的冷贮备不可修系统的可靠度,假设部件的工作时间和转换开关的寿命均服从指数分布、所有随机变量均相互独立,首先根据系统的特征和可靠度的定义研究并求出三部件冷储备系统可靠度的解析式,然后在三部件冷储备系统可靠度研究的基础上建立了n部件冷贮备系统的可靠性关于部件个数n的递推关系式,最终得到系统的可靠度的解析表达式.计算过程对其他多部件系统可靠度的推导有一定的借鉴作用,计算结果具有一定的理论价值.  相似文献   

16.
This paper is concerned with a coherent system consisting of active components and equipped with warm standby components. In particular, we study the random quantity which denotes the number of surviving warm standby components at the time of system failure. We represent the distribution of the corresponding random variable in terms of system signature and discuss its potential utilization with a certain optimization problem.  相似文献   

17.
为了解决开关寿命为连续随机变量且部件工作故障的修理时间与贮备故障后的修理时间各不相同的问题,利用Markov过程理论和Laplace变换方法,研究了有优先权的两不同型部件和两不同修理工组成的温贮备可修系统.假定部件的工作寿命、贮备寿命、工作故障的修理时间和贮备故障的修理时间均服从不同的指数分布,得到了该系统的可靠度Laplace变换和系统的首次故障前平均时间的解析表达式.  相似文献   

18.
An n-unit system provisioned with a single warm standby is investigated. The individual units are subject to repairable failures, while the entire system is subject to a nonrepairable failure at some finite but random time in the future. System performance measures for systems observed over a time interval of random duration are introduced. Two models to compute these system performance measures, one employing a policy of block replacement, and the other without a block replacement policy, are developed. Distributional assumptions involving distributions of phase type introduce matrix Laplace transformations into the calculations of the performance measures. It is shown that these measures are easily carried out on a laptop computer using Microsoft Excel. A simple economic model is used to illustrate how the performance measures may be used to determine optimal economic design specifications for the warm standby.  相似文献   

19.
一类具有备用部件的可修人机系统解的渐近稳定性   总被引:2,自引:0,他引:2  
运用泛函分析的方法 ,通过分析系统主算子的谱特征 ,给出一类具有备用部件的可修人机系统解的渐近稳定性证明 .  相似文献   

20.
This paper proposes a procedure to construct the membership functions of the system characteristics of a redundant repairable system with two primary units and one standby in which the coverage factor is the same for an operating unit failure as that for a standby unit failure. Times to failure and times to repair of the operating and standby units are assumed to follow fuzzified exponential distributions. The α-cut approach is used to extract from the fuzzy repairable system a family of conventional crisp intervals for the desired system characteristics, determined with a set of parametric nonlinear programs using their membership functions. A numerical example is solved successfully to illustrate the practicality of the proposed approach. Because the system characteristics are governed by the membership functions, more information is provided for use by management, and because the redundant system is extended to the fuzzy environment, general repairable systems are represented more accurately and the analytic results are more useful for designers and practitioners.  相似文献   

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