Optimal switchover times between two activities utilizing the same resource

The “gold‐mining” decision problem is concerned with the efficient utilization of a delicate mining equipment working in a number of different mines. Richard Bellman was the first to consider this type of a problem. The solution found by Bellman for the finite‐horizon, continuous‐time version of the problem with two mines is not overly realistic since he assumed that fractional parts of the same mining equipment could be used in different mines and this fraction could change instantaneously. In this paper, we provide some extensions to this model in order to produce more operational and realistic solutions. Our first model is concerned with developing an operational policy where the equipment may be switched from one mine to the other at most once during a finite horizon. In the next extension we incorporate a cost component in the objective function and assume that the horizon length is not fixed but it is the second decision variable. Structural properties of the optimal solutions are obtained using nonlinear programming. Each model and its solution is illustrated with a numerical example. The models developed here may have potential applications in other areas including production of items requiring the same machine or choosing a sequence of activities requiring the same resource. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 186–203, 2002; DOI 10.1002/nav.10008     

对军队院校考核模式改革的思考

考核是军队院校教育教学中的重要组成部分，加强考核模式改革事关军队院校教育的全局。应根据军队院校考核模式的特点、存在的问题以及多元互动式教学模式的构建，为军队院校考核改革提出解决之策。     

有限维修能力下多级保障系统装备时变可用度评估及保障方案优化

备件库存和站点维修能力是影响备件维修周转的重要因素，制约装备使用效果。针对备件需求随任务阶段动态变化的装备保障方案评估和优化问题，考虑站点维修能力对备件维修过程的影响，结合METRIC建模方法和动态排队理论，建立了有限维修能力下多级保障系统装备时变可用度评估模型。在评估模型基础之上，以保障费用为优化目标，装备可用度为约束条件，建立了任务期内多级保障系统保障方案优化模型。以任务期内的最低可用度所对应的备件短缺数为观测值，分析了各项资源的边际效益值，采用边际优化算法对各项资源进行优化计算。算例分析表明，评估模型能够计算多级保障系统任务期内各阶段装备可用度；保障方案优化模型和方法能够得到各项保障资源的优化配置方案。提出的模型和优化方法能够为装备保障人员制定合理的保障方案提供决策支持。     

射线追踪法应用于传播预测的研究

近年来,随着射线追踪法的发展,利用精确的3维数字地图,使精确的电波传播预测成为现实。但是这种方法有很大的缺陷,文中从现阶段城市3维地图建立现状和控制成本的角度考虑,探索了结合射线追踪技术和传统电波传播预测方法,借助计算机辅助设计分析,实现传播覆盖预测的一种新方法,并尝试实现了一个工程案例,进行了相关分析。     

浅谈现代远程教育对武警院校教学的深远影响

武警院校拥有丰富的教育资源，依托武警部队日益健全的内部网络系统，大力开展现代远程教育，能够更加紧密院校与部队的联系，及时了解部队的需求，制定出更加符合部队实际的课程体系，更大限度发挥现有教学资源的效益。由于远程教育具有方便快捷，受时间、空间局限小的特性，弥补了由于武警部队点多、线长、面广，分布相对分散，导致部队官兵学习时间不固定、人员难以集中等不便的问题，为武警部队官兵获取文化知识，学习科学技术提供了新的途径。     

微分对策界栅理论在舰艇作战能力评估中的应用

作战能力是表征战斗舰艇战术技术性能的一项重要指标,如何正确评价舰艇的作战能力一直是军事运筹研究的热点.利用定性微分对策的界栅理论研究了一类作战问题,通过构造捕获区面积和咽喉区域面积,并以此作为动态评估舰艇作战能力的衡量指标.研究结果可为综合评价舰艇作战能力提供一条新途径.     

The effects of model parameter deviations on the variance of a linearly filtered time series

We consider a general linear filtering operation on an autoregressive moving average (ARMA) time series. The variance of the filter output, which is an important quantity in many applications, is not known with certainty because it depends on the true ARMA parameters. We derive an expression for the sensitivity (i.e., the partial derivative) of the output variance with respect to deviations in the model parameters. The results provide insight into the robustness of many common statistical methods that are based on linear filtering and also yield approximate confidence intervals for the output variance. We discuss applications to time series forecasting, statistical process control, and automatic feedback control of industrial processes. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

基于效能分析的工程建设投资分配模型研究

分析了基数滚动切块和层次分析-目标规划(AnalyticHierarchyProcessandGoalProgramming)投资分配模型的利弊,探讨了工程建设投资效能的估计方法,研究建立了基于效能分析的投资分配优化模型.该模型经实际算例分析证明,模型的思路清晰,便于理解和操作,具有较好的实用性.     

A model for step‐stress accelerated life testing

Modern technology is producing high reliability products. Life testing for such products under normal use condition takes a lot of time to obtain a reasonable number of failures. In this situation a step‐stress procedure is preferred for accelerated life testing. In this paper we assume a Weibull and Lognormal model whose scale parameter depends upon the present level as well as the age at the entry in the present stress level. On the basis of that we propose a parametric model to the life distribution for step‐stress testing and suggest a suitable design to estimate the parameters involved in the model. A simulation study has been done by the proposed model based on maximum likelihood estimation. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2003     

一种高效的显式模型检验方法

随着软硬件系统规模和功能的不断扩充,状态空间爆炸问题严重影响了模型检验的进一步发展与应用,成为验证大规模系统的瓶颈.在显式模型检验工具Murphi的基础上,针对其可达状态空间组织存在的问题进行改进,提出了基于整型指针与Fibonacci散列的可达状态空间组织方法,实现了一个高效的显式模型检验原型系统,在确保验证正确的同时有效缩短了验证时间,并能在系统规范不可满足的情况下给出反例,有助于系统设计人员快速定位错误.理论分析和实验结果表明了本方法的有效性.