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171.
This study presents a framework and models for the analysis of government budget allocation into defense and civilian expenditures in situations of uncertainty about the incidence of war. The models display the intricate relationships between security levels, subjective probabilities of the occurrence of war, and potential war damages. We show that poor countries tend to perceive greater probabilities of war than their richer rivals, and that the psychological burden of insecurity is larger when the country’s wealth is larger and when its preference for security is higher. We apply our models to the Israeli–Syrian arms race and show that the higher rate of growth of Israel’s gross domestic product relative to that of Syria is expected to lead to an increase in Syria’s perception of the likelihood of war and to a decrease in Israel’s perception of such a likelihood. We also show that if Syria’s regime becomes ideologically more extreme, the monetary cost of maintaining Israel’s security at the level that it enjoyed prior to the change will be very high, whereas the monetary cost of maintaining Israel’s welfare will be moderate.  相似文献   
172.
任务分配是多导弹协同攻击目标的重要前提,在充分考虑满足复杂战场环境各种约束的条件下,提出了基于混沌粒子群算法的实时动态算法,使得算法在求解WTA问题时具有处理意外目标和任意时刻响应当前战场状态的实时动态特性。并为了解决战场环境中各不确定性因子对新加入目标优先级的影响,提出基于三元区间数表示关联熵的复合物元目标排序方法。  相似文献   
173.
基于故障率和设计特性动态加权的维修性分配法   总被引:1,自引:0,他引:1  
针对国军标中"按故障率和设计特性的维修性分配方法",当可更换单元故障率相差较大时,分配结果与实际明显不符的问题,采用动态加权模型,对国军标的分配方法进行了改进,提出了"基于故障率和设计特性动态加权的维修性分配法",弥补了国军标分配方法的不足。通过理论分析、论证、算例比较和维修性试验验证,证明该方法合理可行。  相似文献   
174.
由于"语义鸿沟"的存在,自动图像标注是一项极具挑战性的工作。考虑到图像低层视觉特征与高层语义概念的差异,分别从图像表示与语义建模两个方面来实现自动图像标注。在图像表示方面,提出了一种正则化约束下的非负张量表示方法,用以提取符合人眼视觉直观理解的图像高阶结构特征。在语义建模方面,提出了一种三层贝叶斯模型——扩展隐Dirichlet分配。该模型利用隐变量来实现图像与标注词的关联,并通过一种基于变分推理的期望最大值方法来估计参数。实验结果表明,ELDA模型在大规模数据库NUS-WIDE上的标注结果相较于现有方法有了显著的提高。  相似文献   
175.
战时弹药供应协同调运模型研究   总被引:1,自引:0,他引:1  
弹药协同调运是战时弹药保障工作中的重要环节,其协同调运的合理性将直接影响到弹药保障工作的顺利进行.针对弹药的调运问题,从战时技术实施与应用角度研究弹药的调运问题,以到达需求点的运输时间、弹药输送车数量以及弹药损失量为优化目标,建立一种多目标决策模型,为缩短运输时间、减少弹药输送车数量、提高安全到达需求点的弹药量提供一种实用的方法.  相似文献   
176.
新型装备列装部队,对部队维修保障能力建设提出了更高更新的要求。为加速新型装备战斗力形成,急需一套科学、合理的方法用以确定装备维修任务和规划维修保障资源配置。针对这一问题,本文紧密结合我军实际,构建了新型装备维修任务分配与保障资源规划分析方法体系,规范了新型装备维修分析流程,并对分析过程中的关键技术进行了研究,最后开发了计算机辅助决策分析系统。  相似文献   
177.
基于对军事权潜在危险性和强大破坏力的忧虑,近代宪法力图将其安定在预设的框架之内。但军事权并非与人类的宪政文明天然相容。所以,现代宪法需要以分权理念来消解军事权的集权性、以平等理念来消解军事权的强隶属性、以正义理念来消解军事权的极端性。于是,各国的宪法文本通常需要在军事权的增强与节制、区隔与融合、明确与模糊间作出权衡。另外,理解军事权的宪法规制还应当超越宪法文本,探究那些行宪过程中能够影响甚至决定军事权的隐性规则。从而真正理解政治制度、文化传统、风俗习惯乃至人们之间以默会的方式发挥作用的信念和原则对军事权运作的重大影响。  相似文献   
178.
依据防空反导作战理论和目标分配的要求,对防空导弹反TBM作战指挥中目标分配的关键问题进行了研究。分别对威胁排序方法、拦截可行性条件、目标分配原则和目标分配算法进行了分析,提出了一种反TBM作战指挥中目标分配问题的算法,最后讨论了目标分配的评价问题。通过实际应用表明此方法是切实可行的。  相似文献   
179.
A two‐echelon distribution inventory system with a central warehouse and a number of retailers is considered. The retailers face stochastic demand and replenish from the warehouse, which, in turn, replenishes from an outside supplier. The system is reviewed continuously and demands that cannot be met directly are backordered. Standard holding and backorder costs are considered. In the literature on multi‐echelon inventory control it is standard to assume that backorders at the warehouse are served according to a first come–first served policy (FCFS). This allocation rule simplifies the analysis but is normally not optimal. It is shown that the FCFS rule can, in the worst case, lead to an asymptotically unbounded relative cost increase as the number of retailers approaches infinity. We also provide a new heuristic that will always give a reduction of the expected costs. A numerical study indicates that the average cost reduction when using the heuristic is about two percent. The suggested heuristic is also compared with two existing heuristics. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
180.
Spatial pricing means a retailer price discriminates its customers based on their geographic locations. In this article, we study how an online retailer should jointly allocate multiple products and facilitate spatial price discrimination to maximize profits. When deciding between a centralized product allocation ((i.e., different products are allocated to the same fulfillment center) and decentralized product allocation (ie, different products are allocated to different fulfillment centers), the retailer faces the tradeoff between shipment pooling (ie, shipping multiple products in one package), and demand localization (ie, stocking products to satisfy local demand) based on its understanding of customers' product valuations. In our basic model, we consider two widely used spatial pricing policies: free on board (FOB) pricing that charges each customer the exact amount of shipping cost, and uniform delivered (UD) pricing that provides free shipping. We propose a stylized model and find that centralized product allocation is preferred when demand localization effect is relatively low or shipment pooling benefit is relatively high under both spatial pricing policies. Moreover, centralized product allocation is more preferred under the FOB pricing which encourages the purchase of virtual bundles of multiple products. Furthermore, we respectively extend the UD and FOB pricing policies to flat rate shipping (ie, the firm charges a constant shipping fee for each purchase), and linear rate shipping (ie, the firm sets the shipping fee as a fixed proportion of firm's actual fulfillment costs). While similar observations from the basic model still hold, we find the firm can improve its profit by sharing the fulfillment cost with its customers via the flat rate or linear rate shipping fee structure.  相似文献   
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