装备结构演化规律及重要度分析

以装备设计模块化的现状为依据,运用重要度理论,分析了装备结构演化及其重要度排序的规律。从单一部件逐步演化到5部件结构,以及N部件串并联结构,在此基础上,对演化规律进行了梳理,并对典型结构进行了重要度分析,得到了关于装备结构演化与各部件重要度排序规律,填补了对装备重要度漂移规律的研究空白,为装备可靠性优化设计提供了技术支撑。     

Dynamic signatures and their use in comparing the reliability of new and used systems

The signature of a system with independent and identically distributed (i.i.d.) component lifetimes is a vector whose ith element is the probability that the ith component failure is fatal to the system. System signatures have been found to be quite useful tools in the study and comparison of engineered systems. In this article, the theory of system signatures is extended to versions of signatures applicable in dynamic reliability settings. It is shown that, when a working used system is inspected at time t and it is noted that precisely k failures have occurred, the vector s [0,1]^n‐k whose jth element is the probability that the (k + j)th component failure is fatal to the system, for j = 1,2,2026;,n ‐ k, is a distribution‐free measure of the design of the residual system. Next, known representation and preservation theorems for system signatures are generalized to dynamic versions. Two additional applications of dynamic signatures are studied in detail. The well‐known “new better than used” (NBU) property of aging systems is extended to a uniform (UNBU) version, which compares systems when new and when used, conditional on the known number of failures. Sufficient conditions are given for a system to have the UNBU property. The application of dynamic signatures to the engineering practice of “burn‐in” is also treated. Specifically, we consider the comparison of new systems with working used systems burned‐in to a given ordered component failure time. In a reliability economics framework, we illustrate how one might compare a new system to one successfully burned‐in to the kth component failure, and we identify circumstances in which burn‐in is inferior (or is superior) to the fielding of a new system. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009     

小子样多失效模式系统可靠性竞争模型

为解决小子样多失效模式系统可靠性模型参数的估计问题,首先应用支持向量积建立小子样条件下各故障模式的规律模型,其次利用模型将各故障模式的故障数据由小子样扩充成大样本,再次采用常规的参数估算方法估算各故障模式的分布参数,最后建立多失效模式系统的可靠性竞争模型。利用所提方法,建立了小子样条件下具有两种失效模式的柴油机汽缸套可靠性竞争模型,计算结果与大样本条件下的故障预测数据吻合度较高,说明了方法的有效性。     

软件系统的可靠性综合评估模型研究*

主要研究了软件系统可靠性的评估方法。基于软件系统的基本结构和体系,对软件系统层次可靠性进行分析,并对影响可靠性的因素进行了分析;根据各分系统失效对整体系统失效影响程度的大小,通过事件测试分析得到实际参数,在给出重要度系数的基础上,建立了串并联系统间权重系数模型,并通过Bayes分析建立了软件系统的可靠性综合评估模型,从而达到对软件系统可靠性综合评估的目的。算例表明该可靠性综合评估模型具有一定的工程应用价值。     

基于灰色理论的鱼雷装载可靠性分析

为解决在鱼雷装载可靠度试验数据较少的情况下进行装载可靠性分析困难的问题,利用灰色系统理论及 GM(1,2)建模的思想,研究了鱼雷装载可靠度和工作可靠度之间的灰色关系,基于灰色系统理论建立了两者之间关系的数学模型.计算实例表明,该方法简单实用,可在鱼雷装载可靠度数据样本量较少的情况下对鱼雷装戢可靠度进行有效预测,为鱼雷装载可靠度的评定提供了理论参考.     

装甲火控可靠性建模

装甲武器是陆军及其两栖机械化部队实施地面突击的主要兵器,也是海军陆战部队实施抢滩登陆、岛屿攻防的主要兵器。装甲火控是装甲武器的重要组成部分,其可靠性直接影响装甲武器的打击效能。两栖装甲武器肩负海上、陆上的作战使命,使用环境更加恶劣,可靠性问题更加突出。描述了装甲火控的一般组成、功能及工作方式,基于两栖装甲武器的使用特点,分析了装甲火控基本任务、工作方式和作战环境的关系,建立了不同任务剖面的可靠性模型,为装甲火控可靠性设计、分析提供了一种参考。     

型号研制与产品数据管理

介绍了产品数据管理(PDM)的概念和基本功能,结合当前型号研制的特点和计算机信息技术应用的状况、发展,研究了型号研制产品数据管理的需求、功能及实施,为当前型号研制依靠CIMS技术实现产品数据管理提出了8条基本原则。     

Does Military Spending Nonlinearly Affect Economic Growth in South Africa?

Using annual data collected from 1988 to 2015, this study provides evidence of a non-linear relationship between military spending, economic growth and other growth determinants for the South African economy. The empirical study is based on estimates of a logistic smooth transition regression (LSTR) model and our empirical results point to an inverted U-shaped relationship between military spending and economic growth for the data. Furthermore, our empirical results suggest that the current levels of military spending, as a component of total government expenditure, are too high in the South African economy and need to be transferred towards more productive non-military expenditure in order to improve the performance of economic growth and other growth determinants.     

无源RFID系统中推断式二进制搜索算法

在现有的RFID标准中，一般标签ID都由几个不同含义区间组成。针对这种特点，提出推断式二进制防碰撞算法：在识别每个区间段的ID时，利用某个特定读写器中的前缀库推断该区间段各个位的取值，以便减少待识别标签ID的位数。同时，通过调整参数u，可以对系统可靠性进行控制。仿真实验表明，在没有新前缀出现的情况下，推断式二进制防碰撞算法能够将QT算法的识别速度提高3倍、标签平均响应次数降低3／4。