Scheduling and due‐date quotation in a make‐to‐order supply chain

We consider a manufacturer, served by a single supplier, who has to quote due dates to arriving customers in a make‐to‐order production environment. The manufacturer is penalized for long lead times and for missing due dates. To meet due dates, the manufacturer has to obtain components from a supplier. We model this manufacturer and supplier as a two‐machine flow shop, consider several variations of this problem, and design effective due‐date quotation and scheduling algorithms for centralized and decentralized versions of the model. We perform extensive computational testing to assess the effectiveness of our algorithms and to compare the centralized and decentralized models to quantify the value of centralized control in a make‐to‐order supply chain. Since complete information exchange and centralized control is not always practical or cost‐effective, we explore the value of partial information exchange for this system. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Nash bargaining over allocations in inventory pooling contracts

When facing uncertain demand, several firms may consider pooling their inventories leading to the emergence of two key contractual issues. How much should each produce or purchase for inventory purposes? How should inventory be allocated when shortages occur to some of the firms? Previously, if the allocations issue was considered, it was undertaken through evaluation of the consequences of an arbitrary priority scheme. We consider both these issues within a Nash bargaining solution (NBS) cooperative framework. The firms may not be risk neutral, hence a nontransferable utility bargaining game is defined. Thus the physical pooling mechanism itself must benefit the firms, even without any monetary transfers. The firms may be asymmetric in the sense of having different unit production costs and unit revenues. Our assumption with respect to shortage allocation is that a firm not suffering from a shortfall, will not be affected by any of the other firms' shortages. For two risk neutral firms, the NBS is shown to award priority on all inventory produced to the firm with higher ratio of unit revenue to unit production cost. Nevertheless, the arrangement is also beneficial for the other firm contributing to the total production. We provide examples of Uniform and Bernoulli demand distributions, for which the problem can be solved analytically. For firms with constant absolute risk aversion, the agreement may not award priority to any firm. Analytically solvable examples allow additional insights, e.g. that higher risk aversion can, for some problem parameters, cause an increase in the sum of quantities produced, which is not the case in a single newsvendor setting. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Technical note: Reexamination of all‐or‐none inspection policies in a supply chain with endogenous product quality

This note studies the optimal inspection policies in a supply chain in which a manufacturer purchases components from a supplier but has no direct control of component quality. The manufacturer uses an inspection policy and a damage cost sharing contract to encourage the supplier to improve the component quality. We find that all‐or‐none inspection policies are optimal for the manufacturer if the supplier's share of the damage cost is larger than a threshold; otherwise, the manufacturer should inspect a fraction of a batch. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Asia-Pacific Demand for Military Expenditure: Spatial Panel and SUR Estimates

This article investigates the demand for military expenditure for a sample of key Asia-Pacific countries. Spatial panel demand estimates are presented for three joined spatial units using a fixed-coefficient spatial lag model based on a two-step efficient GMM estimator. Spatial autoregression estimates are next presented for 1991–2015, founded on alternative kinds of country connectivities, such as contiguity, inverse distance, discrete distance, and power-projection considerations. Finally, 11 select countries’ demands for defense equations are estimated using seemingly unrelated regressions. From alternative perspectives, these estimated models indicate how Asia-Pacific countries respond to the defense spending of other countries. In the spatial runs, free riding is prevalent despite the growing military might of China, which apparently is not generally viewed as a threat. For the sample period, the projection of Chinese or American power is a relevant spatial factor. The main threat is reflected in non-U.S. allies’ reaction to U.S. allies’ defense spending during 1991–2015 and to Chinese defense spending after 2002.     

Praying for Rain? Water Scarcity and the Duration and Outcomes of Civil Wars

Recent anecdotal evidence from the civil wars in Somalia and Yemen suggest that water scarcity may shape the dynamics of civil wars. While a considerable body of research has examined the connection between water scarcity (such as low rainfall) and the onset of civil war, very little research has examined how water scarcity may shape the duration and outcomes of civil wars. Looking specifically at rainfall, this paper argues that changes in access to water play a key role in the duration of civil wars. As rainfall declines, there is a reduction in resources available to both the government and the rebel group, leading to a stalemate in fighting. Furthermore, this paper argues that declines in rainfall are felt more acutely by rebel groups who seek to challenge the government through conventional warfare. This paper tests these propositions using hazard models. The results provide robust support for the propositions.     

装备器材保障资源调度决策模型及算法

装备器材保障资源调度问题是一个非常复杂的问题,根据其优化目标要求,从保障时间最短、保障耗费最低、安全性最高3个方面建立了该问题的多目标优化模型,并通过目标优先度决策将其转化为单目标模型;接着,采用两阶段法进行求解,将其分为最优路径决策、器材分配决策两个阶段进行决策优化,在明确资源点到需求点之间的最优路径后再进行器材资源的分配;并分别采用基于小生境的自适应遗传算法和基于生成树的遗传算法进行求解。通过实例分析,求解结果能够满足装备器材保障的要求,表明所构建的决策模型和算法是有效的。     

公共服务均等化视域下新疆南疆教育扶持政策研究

新疆南疆落后的经济社会造成教育发展缓慢、水平低下,大力发展南疆教育具有极端重要性,近年来国家对南疆教育实施了一系列扶持政策并且取得了良好的效果。本文运用公共服务均等化的分析框架,对南疆教育扶持政策所体现出的价值取向、政府职能转变,以及教育公共服务均等化的物质基础和逻辑起点等四个方面进行了理性分析,并从大力发展国民经济、优化资源配置机制和完善转移支付制度三个角度提出优化南疆教育均等化的建议。     

飞机运动态势对航空深弹入水点散布影响分析

航空自导深弹具有结构简单、可靠性高、不受水文条件限制等特点,而且还具有自导捕获和跟踪目标能力,对于提高航空兵部队反潜能力具有重要作用。反潜机投放高度、投放速度等运动态势关系到使用航空自导深弹对目标实施准确打击。针对航空自导鱼雷攻潜实际过程,建立其入水点的散布误差模型和空中弹道模型,并仿真分析反潜机投弹高度、投弹速度对航空自导深弹入水点的影响。     

基于电容式噪声传感器的信号调理电路设计

在航空航天的飞行器遥测试验中,大推力火箭和导弹飞行时,由燃气射流引起的噪声会对飞行器的结构以及载荷造成巨大的危害。电容式噪声传感器由于其频率响应范围宽,被广泛应用于飞行试验中。电容式传感器工作时需要用恒压源供电,且其采集的信号受到外界干扰较大,输出电压值不满足大多数模数芯片转换要求。针对以上问题,设计了恒压源供电模块和隔直分压电路、低通滤波电路等调理模块,使其最终输出电压范围在0~2.5 V,满足模数转换芯片的要求。该噪声传感器的信号调理电路可靠性高,已经成功应用于飞行器发射试验中。     

武器装备效能评估指标体系分析与研究

详细介绍了武器装备效能评估指标的类型,并对它们之间的关系进行了分析。描述了几种效能评估指标的选取方案,并根据指标体系建立的原则,以炮兵装备为例建立了其指标体系,这种指标体系较为全面地反映了炮兵装备的各类效能,为效能评估奠定了基础。