A comparative study of three tool replacement/operation sequencing strategies in a flexible manufacturing system

This paper studies three tool replacement/operation sequencing strategies for a flexible manufacturing system over a finite time horizon: (1) failure replacement—replace the tool only upon failure, (2) optimal preventive tool replacement for a fixed sequence of operations, and (3) joint scheduling of the optimal preventive tool replacement times and the optimal sequence of operations. Stochastic dynamic decision models are used for strategies 2 and 3. The optimization criterion for strategies 2 and 3 is the minimization of the total expected cost over the finite time horizon. We will show through numerical studies that, with the same amount of information, the total expected costs can be reduced considerably by choosing an optimal strategy. Our conclusion is that in flexible manufacturing, optimal tool replacement and optimal operations sequencing are not separate issues. They should be considered jointly to minimize the expected total cost. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 479–499, 2000     

战略决策模拟中的态势表现

战略决策模拟中,态势表现是实现模拟可视化的关键,具有举足轻重的作用,其研究与实现是一项具有相当难度的课题.首先分析战略态势表现所要解决的两个基本问题,即态势数据和可视化表现;其次着眼于两者的分离,按照面向对象的设计思想,提出了一种面向对象的战略态势表现实现思路;最后,给出了开发战略态势表现系统的基本工作思路.在决胜系列战略决策模拟系统的开发中,按照该思路实现了态势表现子系统,较好的满足了模拟需求.     

前苏联发展反卫星武器的回顾

随着军用卫星的种类变化和性能提高 ,以及为谋求外层空间作战的军事优势 ,前苏联一直在积极发展反卫星武器。介绍了前苏联反卫星武器的组成、特点、技术方案及其发展情况 ,最后归纳了关于前苏联反卫星武器的几点看法。     

BP神经网络的收敛问题

研究了BP神经网络的收敛问题。基于随机理论 ,提出了解决网络收敛性问题的随机优选法。该方法不仅在任何条件下都能得到问题的具有一定精度的解答 ,而且收敛速度很快     

Optimal nonmyopic gambling strategy for the generalized Kelly criterion

We consider the optimal wagers to be made by a gambler who starts with a given initial wealth. The gambler faces a sequence of two-outcome games, i.e., “win” vs. “lose,” and wishes to maximize the expected value of his terminal utility. It has been shown by Kelly, Bellman, and others that if the terminal utility is of the form log x, where x is the terminal wealth, then the optimal policy is myopic, i.e., the optimal wager is always to bet a constant fraction of the wealth provided that the probability of winning exceeds the probability of losing. In this paper we provide a critique of the simple logarithmic assumption for the utility of terminal wealth and solve the problem with a more general utility function. We show that in the general case, the optimal policy is not myopic, and we provide analytic expressions for optimal wager decisions in terms of the problem parameters. We also provide conditions under which the optimal policy reduces to the simple myopic case. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 639–654, 1997     

陆军武器装备建设智能化转型思考

智能化战争形态加速演变,为新时代陆军装备建设带来严峻挑战。必须充分认清陆军武器装备建设智能化转型形势任务,正确把握智能化陆战的基本内涵、典型特性和能力要求等需求牵引,科学确立陆军武器装备体系智能化转型总体思路和发展目标,加快推进陆军武器装备体系智能化建设发展,为新型陆军“迈向智能”奠定基础。     

英语教学中自主学习能力的培养

自主学习是语言学习的关键,学生是否能够学好外语取决于自主学习能力的培养。本文阐述了自主学习的理论基础及使用价值,如何培养学生自主学习的能力,更多关注学习方法的相互作用。     

两人多冲突环境下的双矩阵对策集结模型

针对用多个双矩阵对策来描述的两人多冲突环境,首先基于局中人所受到的约束条件,构造局中人面向多冲突环境的可行策略串集合;其次以所有局中人的可行策略串集合建立新的结局空间,构造局中人在新结局空间上的支付函数,进而建立两人多冲突环境下的对策综合集结模型;最后给出了一个军事例子,该算例说明了模型的实用性.     

一类非完整系统的输出反馈控制问题研究

针对一类具有虚拟控制方向和非线性不确定项的非完整系统,研究了其输出反馈控制器的设计问题。采用状态转换技术和反推方法,设计了只依赖于输出值的输出反馈控制器。同时为了处理初值为零的情况,提出了基于第一个子系统输出值的切换控制策略,通过仿真算例说明了控制器的有效性。