Capacity expansion under a service‐level constraint for uncertain demand with lead times

For a service provider facing stochastic demand growth, expansion lead times and economies of scale complicate the expansion timing and sizing decisions. We formulate a model to minimize the infinite horizon expected discounted expansion cost under a service‐level constraint. The service level is defined as the proportion of demand over an expansion cycle that is satisfied by available capacity. For demand that follows a geometric Brownian motion process, we impose a stationary policy under which expansions are triggered by a fixed ratio of demand to the capacity position, i.e., the capacity that will be available when any current expansion project is completed, and each expansion increases capacity by the same proportion. The risk of capacity shortage during a cycle is estimated analytically using the value of an up‐and‐out partial barrier call option. A cutting plane procedure identifies the optimal values of the two expansion policy parameters simultaneously. Numerical instances illustrate that if demand grows slowly with low volatility and the expansion lead times are short, then it is optimal to delay the start of expansion beyond when demand exceeds the capacity position. Delays in initiating expansions are coupled with larger expansion sizes. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009     

基于Floyd算法的常规导弹连续波次作战运输规划

为提高常规导弹连续波次作战效能，对常规导弹连续波次作战运输规划问题进行研究。以Floyd算法为基础，首先生成了作战机动区域的交通网络最短路径、距离矩阵；其次将常规导弹连续波次作战运输过程分解为不同阶段，以运输过程中的整体暴露时间最短为目标，构建了初始规划方案0-1整数规划模型；然后考虑道路通行量及地域容量限制，对初始规划方案中存在的地域容量超过限制及单行道路中会车、超车情况进行逐步循环优化，以得到最佳运输规划方案；最后选择了一个作战案例想定，通过Matlab编程对案例进行了求解，得到了针对此案例的最佳运输规划方案，验证了模型的正确性和算法的有效性。     

指挥院校英语课堂团队教学策略的实验研究

培养指挥类军事院校学员的团队精神，强化团队意识，把建立有效的激励机制等方法贯穿于教学的各个环节中。团队教学方法不仅可以提高指挥类军校学员的团队协作精神，同时团队教学策略又能显著提高指挥类军校学员的英语口语能力。     

集团军跨域应急作战装备保障能力建设研究

加强应急作战装备保障能力建设,是提高战斗力的重要组成部分。本文针对新体制、新形势下的军队战争形态、使命任务和训练要求,分析了集团军跨域应急作战装备保障的主要特点和当前装备保障存在的不足,并在此基础上,从构建理论体系和装备保障平台、人才队伍建设,装备保障模式以及装备保障实战化训练五个方面给出了集团军跨域应急作战装备保障能力建设和应对措施。     

More military base closure? Considering the alternatives*

Despite multiple base closing rounds, the United States Department of Defense still has excess base capacity, and thus President Trump and high-level Defense Department officials are calling for more base closure through the Base Realignment and Closure (BRAC) process. However, another BRAC may not be the optimal solution, because simple base closure is not an efficient way to reduce surplus base capacity. Thus, Defense Department officials should consider other methods to reduce surplus capacity, including reduction in base size, leasing excess base property, or transferring it to another government agency for a variety of alternative uses. The surplus capacity issue also offers an opportunity to DOD to reassess base utilization, to update base requirements with current and future force structure. While BRAC focuses on American military bases, the process and alternatives also have international applications.