价值工程在引信方案论证中的应用

本文结合我国引信产品方案论证的实际,论述了应用价值工程原理,综合考虑引信战术性能、可靠性、安全性、寿命、费用等进行引信方案论证的方法、步骤和原则。     

Evasion policies for a vessel being chased by pirate skiffs

Piracy attack is a serious safety problem for maritime transport worldwide. Whilst various strategic actions can be taken, such as rerouting vessels and strengthening navy patrols, this still cannot completely eliminate the possibility of a piracy attack. It is therefore important for a commercial vessel to be equipped with operational solutions in case of piracy attacks. In particular, the choice of a direction for rapidly fleeing is a critical decision for the vessel. In this article, we formulate such a problem as a nonlinear optimal control problem. We consider various policies, such as maintaining a straight direction or making turns, develop algorithms to optimize the policies, and derive conditions under which these policies are effective and safe. Our work can be used as a real‐time decision making tool that enables a vessel master to evaluate different scenarios and quickly make decisions.     

微波系统前端放大器的计算机辅助设计与实现

本文介绍了微波放大器机辅设计的各种方法,介绍了考虑各种因素后所编制的LCAD软件及其特点。用LCAD软件设计制作了两个放大器,一个已成功地用于某雷达中,其指标达到国内同类产品领先水平,另一个也有较高的性能指标,而且两者的理论值与实测数据十分吻合。这在微波放大器的设计中是很难达到的,说明了LCAD软件是十分成功的。     

Estimating the lead-time demand distribution for an autocorrelated demand by the pearson system and a normal approximation

The exact first four moments of lead-time demand L are derived for an AR(1) and a MA(1) demand structures where the arbitrary lead-time distribution is assumed to be independent of the demand structure. These moments then form a basis for the Pearson curve-fitting procedure for estimating the distribution of L. A normal approximation to L, a version of the central limit theorem, is obtained under some general conditions. Reorder points (ROPs) of an inventory system are then estimated based on the Pearson system and a normal approximation. Their performances are evaluated. Numerical investigation shows that the Pearson system performs extremely well. The normal approximation, however, is good only for some limited cases, and is sensitive to the choice of the lead-time distribution. A possible improvement is noted.     

机动式指挥自动化系统电磁兼容性设计

电磁兼容性设计是机动式指挥自动化系统的重要环节。电磁屏蔽、滤波、接地等技术是电磁兼容性设计的重要方法。电磁屏蔽是抑制辐射干扰的一种有效隔离方法。滤波是抑制传导干扰最直接、最有效的方法,对于瞬态脉冲干扰,最有效的办法是采用脉冲吸收技术。接地的综合考虑,对产品电磁兼容性有至关重要的意义。针对机动式指挥自动化系统的结构和组成特点,给出了一些具体的电磁干扰抑制设计,对满足实际的电磁兼容性方面作出了有意义的尝试。     

美军军法官制度简介

美军的政治性工作一般由两“师”完成,一个是牧师,另一个则是随军律师。而随军律师是处理法律问题的军官的泛称,主要指的就是军法官(JudgeAdvocate)和其领导下的法律助手、律师等。2003年的伊拉克战争中,美军约有103位军法官、62名法律专职助手深入战场。①他们在拘押战犯,发表对外声明,与英军建立联合军事司法系统和提供交战规则,促使官兵遵守国际战争法、军事行动法上起了相当大的作用。一、起源与概念在美军中没有法律战的明确词汇和概念,但是这并不意味着美军不运用法律武器以达到军事目的。相反,他们相当擅长和重视这一工作,而且已有…     

椭圆型方程曲线网格的快速生成方法

本文在用椭圆型方程的网格生成方法生成曲线网格时,通过比较四种常用的计算格式,得到了收敛速度较快的生成方法。在计算流体力学领域,对于边界形状随时间变化的流动问题的数值计算,及自适应网格的生成等同题,生成网格的收敛速度直接影响流场的计算速度。在上述情况下使用本文的结果,能有效的减少机时,提高计算效率。     

Workload distribution of discrete‐time parallel queues with two servers

We study discrete‐time, parallel queues with two identical servers. Customers arrive randomly at the system and join the queue with the shortest workload that is defined as the total service time required for the server to complete all the customers in the queue. The arrivals are assumed to follow a geometric distribution and the service times are assumed to have a general distribution. It is a no‐jockeying queue. The two‐dimensional state space is truncated into a banded array. The resulting modified queue is studied using the method of probability generating function (pgf) The workload distribution in steady state is obtained in form of pgf. A special case where the service time is a deterministic constant is further investigated. Numerical examples are illustrated. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 440–454, 2000     

弹炮混编防空群兵力分配模型

针对对付现代日益发展的空袭手段的一种有效方法--弹炮混编防空布势中存在的防空武器种类繁多,兵力分配复杂,难以充分发挥各自效能的问题,建立了非线性规划模型,利用动态规划对该模型进行分析,运用拉格朗日降维法进行降维,将三维降为二维.经防空作战的实例验证该算法不但能将两维降到单维,而且还可以将多维降到单维,能节省计算机的内存使用率,提高仿真计算的速度,符合信息化条件下指挥决策实时化的要求且分配效果较好.     

大空间建筑防火设计应注意的问题

大空间建筑是近年发展起来的新兴建筑。本文分析了大空间建筑的火灾危险性 ,并就其防火设计提出了对策。