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261.
作战功能是作战节点具备的履行作战活动的能力,作战任务是作战节点履行作战活动的原因和目的.首先,从研究作战任务、作战功能、作战活动等基本概念着手,分析作战任务、作战功能和作战活动三者之间的关系.然后,建立模型,通过数学关系式a=A(f,t)说明作战活动是作战功能、作战任务的二维函数,作战节点履行什么作战活动由作战功能和需要完成的作战任务共同决定;在此基础上,构建作战功能、作战任务、作战活动三者的关系矩阵,用关系矩阵的形式分析、描述作战节点履行的作战活动;最后,结合IDEF0建模方法,给出分析、确定作战活动的基本步骤.  相似文献   
262.
Operational processes are usually studied in terms of stochastic processes. The main information measure used for predictability of stochastic processes is the entropy rate, which is asymptotic conditional entropy, thus not suitable for application over a finite horizon. We use the conditional entropy to study the predictability of stochastic processes over the finite horizon. It is well‐known that the conditional entropies of stationary processes decrease as the processes evolve, implying that, on average, their pasts become more informative about prediction of their future outcomes. Some important operational processes such as martingale, models for maintenance policies, nonhomogeneous Poisson, and mixed Poisson processes are nonstationary. We show that as a nonstationary process evolves, it may provide more information or less information about the future state of the system. We develop results for comparing the predictability of stochastic processes. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
263.
在分析武器装备使用中实际可靠性水平的基础上,论述了外界因素和操作人员对武器装备可靠性的影响,提出了在使用维护中武器装备可靠性保障的思路和措施。  相似文献   
264.
变异系数在可靠性中的应用   总被引:6,自引:0,他引:6  
对使用变异系数描述随机变量的离散程度进行分析,推导了可靠性工程中常用的4种概率分布的变异系数与分布参数之间的关系.以机械产品整机及其零部件不同失效模式的寿命变异系数的取值范围为实例,说明了变异系数在可靠性工程中的应用.  相似文献   
265.
简要阐述了建筑消防设施的主要分类、作用、维护管理要求等,着重分析了消防供电、供水、设施联动、人机协调等方面可靠性存在的问题,从落实检测保养、人员素质、预案演练、监督检查等方面分析问题形成的原因,并提出解决问题的几点措施。  相似文献   
266.
The primary objective of this work is to introduce and perform a detailed study of a class of multistate reliability structures in which no ordering in the levels of components' performances is necessary. In particular, the present paper develops the basic theory (exact reliability formulae, reliability bounds, asymptotic results) that will make it feasible to investigate systems whose components are allowed to experience m ≥ 2 kinds of failure (failure modes), and their breakdown is described by different families of cut sets in each mode. For illustration purposes, two classical (binary) systems are extended to analogous multiple failure mode structures, and their reliability performance (bounds and asymptotic behavior) is investigated by numerical experimentation. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 167–185, 2002; DOI 10.1002/nav.10007  相似文献   
267.
268.
The significance of integrating reliability into logistics performance has been established [The Logistics Performance Index and Its Indicators, World Bank International Trade and Transport Departments, (2010)]. Hence, as a response to the work by the World Bank, the present article aims to evaluate the performance index Rb,d of logistics systems as the probability that a specified demand d can be distributed successfully through multistate arc capacities from the source to the destination under the constraint that the total distribution cost should not exceed the cost limitation b. This article provides a pioneering approach for a straightforward computation of the performance index Rb,d. The proposed algorithm is a hybrid between the polynomial time capacity‐scaling algorithm, which was presented by Edmonds and Karp [JACM 19 (1972)], and the decomposition algorithm, which was presented by Jane and Laih [IEEE (2008)]. Currently, the proposed approach is the only algorithm that can directly compute Rb,d. An illustration of the proposed algorithm is presented. The results of the computational experiments indicate that the presented algorithm outperforms existing algorithms. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012  相似文献   
269.
武器雷达装备RCM分析决策系统   总被引:1,自引:0,他引:1  
详细介绍了武器雷达装备RCM分析决策系统的体系结构、功能模块划分和数据库设计方法,并给出了系统的实现方案以及后续开发的设想。  相似文献   
270.
A 2‐dimensional rectangular k‐within‐consecutive‐(r, s)‐out‐of‐(m, n):F system consists of m × n components, and fails if and only if k or more components fail in an r × s submatrix. This system can be treated as a reliability model for TFT liquid crystal displays, wireless communication networks, etc. Although an effective method has been developed for evaluating the exact system reliability of small or medium‐sized systems, that method needs extremely high computing time and memory capacity when applied to larger systems. Therefore, developing upper and lower bounds and accurate approximations for system reliability is useful for large systems. In this paper, first, we propose new upper and lower bounds for the reliability of a 2‐dimensional rectangular k‐within‐consecutive‐(r, s)‐out‐of‐(m, n):F system. Secondly, we propose two limit theorems for that system. With these theorems we can obtain accurate approximations for system reliabilities when the system is large and component reliabilities are close to one. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005  相似文献   
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