几何分布定数截尾步加试验的最优设计

在逐步type-II结尾场合下,研究产品简单步进应力加速寿命试验的优化设计。假定产品服从几何分布,讨论了几何分布产品加速方程如何建立,利用次序统计量的大样本性质,得到相应的Fisher信息矩阵,以对数特征寿命极大似然估计的渐进方差最小为准则结合Fisher信息矩阵,给出了步进应力加速寿命试验的最优分配比例,通过模拟验证最优设计的有效性。     

基于模糊层次分析法的雷达导引头干扰效能评估

为评估对主动雷达导引头的干扰效能,结合导引头工作原理和功能特性,运用模糊数学理论,构建了对雷达导引头干扰效能进行评估的指标体系,建立了二级模糊评判模型,采用正态分布形式构造隶属函数,并利用指数标度的层次分析法(AHP)确定各因素的权重,使得判断矩阵的一致性指标得到改善,实现对雷达导引头的量化评估。最后选择噪声干扰为例进行模糊综合评判,实例分析结果表明该雷达导引头干扰效能模糊评判模型具有实用性,其评估结果可为干扰措施的选择提供参考。     

Damage accumulation and probability of kill for gun and target engagements

Determination of the gunfire probability of kill against a target requires two parameters to be taken into consideration: the likelihood of hitting the target (susceptibility) and the conditional probability of kill given a hit (vulnerability). Two commonly used methods for calculating the latter probability are (1) treating each hit upon the target independently, and (2) setting an exact number of hits to obtain a target kill. Each of these methods contains an implicit assumption about the probability distribution of the number of hits‐to‐kill. Method (1) assumes that the most likely kill scenario occurs with exactly one hit, whereas (2) implies that achieving a precise number of hits always results in a kill. These methods can produce significant differences in the predicted gun effectiveness, even if the mean number of hits‐to‐kill for each distribution is the same. We therefore introduce a new modeling approach with a more general distribution for the number of hits‐to‐kill. The approach is configurable to various classes of damage mechanism and is able to match both methods (1) and (2) with a suitable choice of parameter. We use this new approach to explore the influence of various damage accumulation models on the predicted effectiveness of weapon‐target engagements.     

The structural origins of social cohesion: the dynamics of micro-solidarity in 1991–1995 Wars of Yugoslav Succession

This article explores the dynamics of social cohesion on the frontline. It attempts to show how micro-level solidarities largely depend on macro level organisational processes. I argue that frontline social cohesion is often the product of social development linked with the organisational structure. This general argument is applied to the case studies of two armed forces involved in the 1991–1995 Wars of Yugoslav Succession – the Croatian Army (HV) and the Bosnian Serb Army (VRS). Drawing on in-depth interviews with the former combatants I show how HV social cohesion played an important role in winning the war and how these networks of micro-level solidarity were shaped by long term organisational development.     

基于神经网络TSP算法的防空作战火力分配

基于神经网络TSP算法建立了防空作战火力分配模型,并通过在计算机上仿真运行了实例,优化了火力分配方案.这是对解决防空作战火力分配问题的一种有益的尝试与探索,同时也对防空作战指挥决策和理论研究以及指挥自动化系统建设提供了参考.     

防空智能火力分配的实现方法

防空指挥当中火力分配的原则有很多,从目标威胁度和射击有利度等方面对火力分配原则加以分析.同时介绍了在Windows环境下,利用Visual C 开发工具对智能火力分配原则进行代码编程的实现方法,重点阐述了基于面向对象的编程思想,运用多线程和对象链表的编程手法解决了火力分配过程中各目标对象和火力单位对象的属性参数实时处理问题.     

高技术条件下炮兵作战火力优化模型

由于能给敌军造成大量的毁伤 ,炮兵被誉为“战争之神”。但是 ,由于可得到的炮兵部队数量、弹药和时间所限 ,炮兵不可能对战场所有可得到的目标射击。炮兵必须决定哪些目标可用炮兵射击 ,以及如何射击。考虑到未来战场将充斥着大量目标 ,炮兵要求使用一种自动目标处理系统。将提出一个炮兵优化模型 ,模型的目的是快速对目标价值排序 ,然后以最佳的炮兵兵力、火力分配对选择的目标进行射击。     

Log‐concave and concave distributions in reliability

Nonparametric classes of life distributions are usually based on the pattern of aging in some sense. The common parametric families of life distributions also feature monotone aging. In this paper we consider the class of log‐concave distributions and the subclass of concave distributions. The work is motivated by the fact that most of the common parametric models of life distributions (including Weibull, Gamma, log‐normal, Pareto, and Gompertz distributions) are log‐concave, while the remaining life of maintained and old units tend to have a concave distribution. The classes of concave and log‐concave distributions do not feature monotone aging. Nevertheless, these two classes are shown to have several interesting and useful properties. We examine the closure of these classes under a number of reliability operations, and provide sharp reliability bounds for nonmaintained and maintained units having life distribution belonging to these classes. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 419–433, 1999     

基于RBF神经网络的背景估计及红外小目标检测

利用RBF神经网络的函数逼近特性,得到了一种红外图像背景估计算法,进而提出了一种检测红外小目标的方法。利用有目标和没有目标的真实红外图像对此算法进行检测,背景估计效果理想,小目标检测效果理想,证明该算法是可行有效的。     

Parametric inference for component distributions from lifetimes of systems with dependent components

In system reliability analysis, for an n ‐component system, the estimation of the performance of the components in the system is not straightforward in practice, especially when the components are dependent. Here, by assuming the n components in the system to be identically distributed with a common distribution belonging to a scale‐family and the dependence structure between the components being known, we discuss the estimation of the lifetime distributions of the components in the system based on the lifetimes of systems with the same structure. We develop a general framework for inference on the scale parameter of the component lifetime distribution. Specifically, the method of moments estimator (MME) and the maximum likelihood estimator (MLE) are derived for the scale parameter, and the conditions for the existence of the MLE are also discussed. The asymptotic confidence intervals for the scale parameter are also developed based on the MME and the MLE. General simulation procedures for the system lifetime under this model are described. Finally, some examples of two‐ and three‐component systems are presented to illustrate all the inferential procedures developed here. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012