Flow computations past a triangular boattailed projectile

This paper presents a computational study of the air flow past a triangular boattailed projectile. The study shows that there is a single normal shock wave impinges the projectile at transonic speeds. At supersonic speeds, the formed shock waves are smeared compared to a conical boattailed projectile. Also, there is a reduction of the wake region behind the triangular base and the rear stagnation point is nearer to the projectile base resulting in base drag reduction. Moreover, there is an improvement of the stability of the triangular boattailed projectile since a lower overturning moment is incurred.     

Newsvendor bounds and heuristics for serial supply chains with regular and expedited shipping

We study an infinite‐horizon, N‐stage, serial production/inventory system with two transportation modes between stages: regular shipping and expedited shipping. The optimal inventory policy for this system is a top–down echelon base‐stock policy, which can be computed through minimizing 2N nested convex functions recursively (Lawson and Porteus, Oper Res 48 (2000), 878–893). In this article, we first present some structural properties and comparative statics for the parameters of the optimal inventory policies, we then derive simple, newsvendor‐type lower and upper bounds for the optimal control parameters. These results are used to develop near optimal heuristic solutions for the echelon base‐stock policies. Numerical studies show that the heuristic performs well. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

基于云-神经网络的液体火箭发动机故障检测方法

根据故障检测原理,研究和实现了基于云-神经网络的液体火箭发动机故障检测方法。根据训练结果、测试结果和故障检测结果可以看出,云-神经网络用于液体火箭发动机的故障检测是可行的,经过历次试车数据验证,该方法没有误报警和漏报警。     

优化边防情报资源管理模式探析

边防情报在公安边防部门开展对敌斗争,维护沿边沿海地区政治、社会稳定和预防打击犯罪中发挥着越来越重要的作用。对边防情报进行科学管理,更好地发挥边防情报的服务功能,需要对边防情报资源管理模式进行优化。引入知识管理模式,以期实现边防情报资源管理模式的优化。     

武警总队应急车辆故障诊断系统研究

将人工神经网络和基于案例推理技术结合用于车辆故障诊断系统中,构建了ANN与CBR结合模型,阐述了各子系统的基本功能及相互关系,并对关键技术进行了详细解释。实例诊断表明,ANN和CBR方法的结合有效地弥补了它们各自的缺陷,提高了应急条件下车辆的维修保障能力。     

Intellectual spring cleaning: it’s time for a military “Do Not Read” list; and some sources that should be on that list

Military reading lists, intended to promote professional reading and in turn enhance education and develop critical thinking skills and sound judgement, recommend key texts to military personnel. This is a noble intent but the lists themselves, while generally good, are not flawless. Critiques of military reading lists often focus on what sources they are missing. This article offers its own critique but from a different perspective. It does so by analysing why some sources, which have become outdated, are based on faulty or incomplete research, have been thoroughly disproven, or some combination of the above, nevertheless linger on military reading lists. It then offers a short list of such sources, which it recommends be either removed from existing reading lists or accompanied by other sources that place the original source in appropriate historical context. Where applicable, it also recommends alternative sources that provide insights into the same subject matter. In so doing, this article is intended generate debate and to assist militaries to achieve a better balance between evaluation, induction and retention of valid knowledge on one hand, and rejection of outdated or flawed knowledge on the other.     

基于动态模糊综合评判的反后坐装置故障预测模型

针对反后坐装置故障预测中的诸多模糊信息和模糊因素,基于传统的模糊综合评判方法,提出将动态模糊综合评判方法用于故障预测,给出了动态权重系数及模糊关系矩阵的确定方法,以反后坐装置为例对动态模糊综合评判方法予以说明。并将模糊综合评判与产生式规则融合,利用复合推理机制提高预测结果的准确性。     

基于系统分层与故障树的故障诊断方法

提出了一种新的故障诊断与定位方法 ,该方法利用产品在结构和功能上具有一定层次的特点进行结构和功能的分解 ,这样将故障缩小在一定的功能范围内 ,然后在一个较小范围内利用故障树进行诊断和故障定位。该方法比较适合于电子系统的故障诊断和定位 ,具有简洁、高效的特点。     

如何读懂英美报刊的标题

迅速读懂英美报刊的标题对搜集处理信息,了解世界动态意义重大.要达到这一目的,就必须了解报刊英语标题的特点,具备一定的西方国家社会发展和文化历史等背景知识.     

基于模糊推理的舰炮故障检测方法研究

基于模糊推理知识和模糊神经网络的理论,根据舰炮运转时发出的声音信号,提出了舰炮系统的故障检测诊断方案,详细介绍了信号提取的方法和故障分析的算法.