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921.
This article proposes two dual‐ascent algorithms and uses each in combination with a primal drop heuristic embedded within a branch and bound framework to solve the uncapacitated production assembly distribution system (i.e., supply chain) design problem, which is formulated as a mixed integer program. Computational results indicate that one approach, which combines primal drop and dual‐ascent heuristics, can solve instances within reasonable time and prescribes solutions with gaps between the primal and dual solution values that are less than 0.15%, an efficacy suiting it for actual large‐scale applications. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
922.
923.
根据传热学理论和热网络法,以某型直升机尾减速器弧齿锥齿轮传动系统为研究对象,建立了其温度场Simulink仿真计算模型。基于该模型,计算获得该传动系统正常润滑条件下的稳态温度场,并以它作为初始条件计算分析该传动系统失去润滑条件下的瞬态温度场,为预测该弧齿锥齿轮传动系统在失去润滑条件下的干运转生存能力提供理论依据。  相似文献   
924.
针对航空导航的特点,对现有航空导航装备的特点进行了分析,并结合未来作战的需求,给出了航空导航技术的发展方向,主要是组合式导航体制,将卫星导航与惯导的组合进一步与地形辅助导航、地球物理导航、地磁导航等方式结合起来.  相似文献   
925.
信息化条件下防空兵作战依托防空兵指挥信息系统,已经将防空兵各个作战要素联结到了一起,初步具备了网络化作战的雏形.而恰当的指挥控制方式是实施高效防空兵网络化作战的关键问题之一.首先剖析了防空兵网络化作战给指挥控制带来的新特点,而后构建了防空兵网络化作战指挥控制方式的概念模型,在此基础上提出了适应防空兵网络化作战的指挥控制方式是自适应指挥控制方式.并研究了防空兵网络化作战实施自适应指挥控制方式的必要性、可行性、内在机理以及实现的途径.  相似文献   
926.
Measuring the relative importance of components in a mechanical system is useful for various purposes. In this article, we study Birnbaum and Barlow‐Proschan importance measures for two frequently studied system designs: linear consecutive k ‐out‐of‐ n and m ‐consecutive‐ k ‐out‐of‐ n systems. We obtain explicit expressions for the component importance measures for systems consisting of exchangeable components. We illustrate the results for a system whose components have a Lomax type lifetime distribution. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
927.
This study develops the concepts of fourth generation operations and the associated principles. First, the concept of fourth generation operations is introduced and defined. Fourth generation operations are the evolution and extension of third and fourth generation warfare based on a change of tactics, technology, and combatants. These operations are currently ongoing in Afghanistan and Iraq, and with the global war on terrorism. Based on the framework of US joint doctrine, the supporting principles of fourth generation operations are developed. This requires the introduction of the principle of Population Perception.  相似文献   
928.
We consider the single server Markovian queue subject to Poisson generated catastrophes. Whenever a catastrophe occurs, all customers are forced to abandon the system, the server is rendered inoperative and an exponential repair time is set on. During the repair time new arrivals are allowed to join the system. We assume that the arriving customers decide whether to join the system or balk, based on a natural linear reward‐cost structure with two types of rewards: A (usual) service reward for those customers that receive service and a (compensation) failure reward for those customers that are forced to abandon the system due to a catastrophe. We study the strategic behavior of the customers regarding balking and derive the corresponding (Nash) equilibrium strategies for the observable and unobservable cases. We show that both types of strategic behavior may be optimal: to avoid the crowd or to follow it. The crucial factor that determines the type of customer behavior is the relative value of the service reward to the failure compensation. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
929.
ABSTRACT

This article discusses the Rhodesian Front regime propaganda warfare strategy during Zimbabwe’s war of liberation. It uses the case of the Chilonga area of Chiredzi located in the south-east of Zimbabwe to demonstrate that propaganda warfare was introduced as a measure to counter guerrilla infiltration and civilian cooperation with them. Drawing on ideas of military anthropology vis-à-vis the importance of cultural awareness in counterinsurgency, the paper argues that the efforts of the Rhodesian Front regime to use propaganda were fruitless. This is because they mostly ignored the culture of the Shangani, local people. Despite that, there were other reasons for the failure of the Rhodesian Front’s propaganda strategy, including the lack of conformity between politics and military action.  相似文献   
930.
Croatia's successful bid for independence was one of the defining moments of the immediate post-Cold War period. Nevertheless, the means that Croatia used to obtain independence remains relatively unexamined by academics. This article focuses on the early period of Croatia's bid for secession, and specifically the role that Yugoslavia's policy of Total National Defence played in facilitating its independence. Unlike in Slovenia, where the legacies of Total National Defence facilitated Slovenia's bid for secession, in Croatia the decision of its political leaders meant that the country largely neglected its positive legacies, resulting in a protracted four-year struggle.  相似文献   
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