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61.
Burn‐in procedure is a manufacturing technique that is intended to eliminate early failures of system or product. Burning‐in a component or system means to subject it to a period of use prior to being used in field. Generally, burn‐in is considered expensive and so the length of burn‐in is typically limited. Thus, burn‐in is most often accomplished in an accelerated environment in order to shorten the burn‐in process. A new failure rate model for an accelerated burn‐in procedure, which incorporates the accelerated ageing process induced by the accelerated environmental stress, is proposed. Under a more general assumption on the shape of failure rate function of products, which includes the traditional bathtub‐shaped failure rate function as a special case, upper bounds for optimal burn‐in time will be derived. A numerical example will also be given for illustration. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
62.
借助Z上矩阵A∈Mm×n(Z)的标准形式D=VAU=diag(d1,d2,…,dq,0,…,0),得到了整环上不定方程组AX=B的通解公式以及矩阵初等变换法.  相似文献   
63.
This paper investigates the nature of two military alliances under Chinese threat. The findings are as follows: First, South Korea does not consider China a significant threat while Japan and the United States have recognized China as a serious threat since the 1990s and the 2000s, respectively. Second, the relationship between South Korea and the United States is a true military alliance for all time periods, but the nature of the alliance has changed since the 1970s. Third, although Japan began to form an alliance relationship with the United States in the 1990s, Japan is considered a more significant ally by the United States. This paper implies that, should China provoke a military confrontation, it might be difficult to deduce a common solution among the three countries because of the different response to military threats from China.  相似文献   
64.
Kovenock and Roberson's [2011] comment provides initial work which has the potential, when suitably extended, to advance the research frontier. Kovenock and Roberson's paper consists of three sections. The first section is an interesting introduction. The second section, titled ‘Model and Main Result,’ provides no contribution beyond Hausken [2008a]. It consists of Equations (1)–(10) which are equivalent to equations developed by Hausken, and Equation (11) which is equivalent to the utility requirements u???0 and U???0 provided after Equation (17) in Hausken. The third section provides interesting ideas about mixed-strategy equilibria that can be extended in future research.  相似文献   
65.
分析了战时装备调配保障决策的特点,运用模糊聚类分析法对装备调配保障对象进行了分组和优先级排序,以此为基础,运用目标规划法构建了战时装备调配保障决策模型,最后,通过实例验证了模型的可行性和有效性.  相似文献   
66.
基于ABAQUS有限元软件,采用主从接触算法模拟桩-土相互作用、修正剑桥模型作为土体本构模型,通过在桩顶施加竖向位移荷载以及合适的网格划分技术建立了较为符合压入管桩压桩实际的有限元模型。利用得到的有限元模型模拟了压入管桩压桩产生的挤土位移场,对不同泊松比时压入管桩单桩挤土位移场进行了对比分析。结果表明:不同泊松比时竖向和水平挤土位移场沿深度方向和径向的分布规律趋于一致;土体泊松比的变化会对压入管桩压桩产生的竖向和水平挤土位移场产生较大影响;泊松比越大,压桩产生的竖向和水平挤土位移越大。  相似文献   
67.
Information Management (IM) – the systematic ordering, processing and channelling of information within organisations – forms a critical component of modern military command and control systems. As a subject of scholarly enquiry, however, the history of military IM has been relatively poorly served. Employing new and under-utilised archival sources, this article takes the British Expeditionary Force (BEF) of the First World War as its case study and assesses the extent to which its IM system contributed to the emergence of the modern battlefield in 1918. It argues that the demands of fighting a modern war resulted in a general, but not universal, improvement in the BEF’s IM techniques, which in turn laid the groundwork, albeit in embryonic form, for the IM systems of modern armies.  相似文献   
68.
During the Nigerian Civil War (1967–1970), France chose to support Biafra, but only on a limited scale, providing mercenaries and obsolete weaponry to Ojukwu's regime. General Charles de Gaulle's assistance to Ojukwu was conditioned by the French military drawdown after 1961, the increased power of French secret services on the continent, and the interventions in Katanga (1960–1963), Gabon (1964) and Chad (1968–1972). France supported Biafra primarily to protect its former colonies from Nigeria, stop Soviet subversion and acquire an economic foothold in the oil-rich Niger Delta. De Gaulle chose a limited strategy for two reasons. If Biafra won the war, France would be Biafra's greatest ally. If Nigeria won the war, France could extricate itself from the situation relatively easily and re-establish relations with the Nigerian government, which is what ultimately occurred.  相似文献   
69.
十八大首次将经济、政治、文化、社会和生态五大建设并列,强调“五位一体”建设中国特色社会主义。由此,中国特色社会主义发展布局历经四个阶段,即:“一个中心,两个基本点”的战略布局,“三位一体”发展布局,“四位一体”发展布局,“五位一体”发展布局。“五位一体”总体布局是一个相互联系、相互协调、相互促进、相辅相成的有机整体,对于开创中国特色社会主义事业新局面意义重大,为到本世纪中叶基本实现社会主义现代化,提供了有力支撑。  相似文献   
70.
文化安全的关键在意识形态,意识形态领域中的关键问题是价值观掌控问题。作为文化传播的主要组成部分,网络舆情对文化安全的表层和深层结构都有重要影响。本文从文化安全视角下切入,结合新疆高校网络舆情调研,分析了文化安全面临的冲击与挑战,并提出了基于文化安全保障下的新疆高校网络舆情有效管理方式和路径。  相似文献   
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