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151.
One of the most important questions affecting U.S. national security is the future size of the U.S. nuclear stockpile. While there is clear consensus within the U.S. government on the need to reduce the size of the arsenal, there is none on the best path to achieve these cuts; on the type of deterrent necessary to deal with future threats; or on the size of the production complex needed to support that arsenal. Creating a strategic commission to review these questions, as contemplated in the Fiscal 2008 House Defense Authorization bill, is a necessary first step to establish a sensible nuclear policy. The Reliable Replacement Warhead, which has the potential to transform the complex while preserving the current moratorium on nuclear testing, is a program worth exploring further if it stays within congressionally mandated bounds. As Congress considers both programmatic and policy matters related to U.S. nuclear weapons, it is vital that we also renew and strengthen U.S. leadership on nuclear nonproliferation.  相似文献   
152.
We revisit the causal relationship between military spending and unemployment in the G7 countries applying a bootstrap panel causality analysis that accounts for both cross-sectional dependence and for heterogeneity across countries. Using per capita real GDP as a controlled variable, we found a unidirectional causality running from military spending to unemployment for Canada, Japan, and the US, one-way causality running from unemployment to military spending for France and Germany, and bidirectional causality for Italy and the UK. The empirical evidence does not seem to provide consistent results regarding the causal relationship between military spending and unemployment in G7 countries.  相似文献   
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154.
Consider a patrol problem, where a patroller traverses a graph through edges to detect potential attacks at nodes. An attack takes a random amount of time to complete. The patroller takes one time unit to move to and inspect an adjacent node, and will detect an ongoing attack with some probability. If an attack completes before it is detected, a cost is incurred. The attack time distribution, the cost due to a successful attack, and the detection probability all depend on the attack node. The patroller seeks a patrol policy that minimizes the expected cost incurred when, and if, an attack eventually happens. We consider two cases. A random attacker chooses where to attack according to predetermined probabilities, while a strategic attacker chooses where to attack to incur the maximal expected cost. In each case, computing the optimal solution, although possible, quickly becomes intractable for problems of practical sizes. Our main contribution is to develop efficient index policies—based on Lagrangian relaxation methodology, and also on approximate dynamic programming—which typically achieve within 1% of optimality with computation time orders of magnitude less than what is required to compute the optimal policy for problems of practical sizes. © 2014 Wiley Periodicals, Inc. Naval Research Logistics, 61: 557–576, 2014  相似文献   
155.
The construction of convex and concave envelopes of real‐valued functions has been of interest in mathematical programming for over 3 decades. Much of this interest stems from the fact that convex and concave envelopes can play important roles in algorithms for solving various discrete and continuous global optimization problems. In this article, we use a simplicial subdivision tool to present and validate the formula for the concave envelope of a monomial function over a rectangle. Potential algorithmic applications of this formula are briefly indicated. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
156.
We analyze the moments of the random time required for a vehicle to traverse a transportation network link of arbitrary length when its speed is governed by a random environment. The problem is motivated by stochastic transportation network applications in which the estimation of travel time moments is of great importance. We analyze this random time in a transient and asymptotic sense by employing results from the field of fluid queues. The results are demonstrated on two example problems. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
157.
In this paper, we discuss two‐dimensional failure modeling for a system where degradation is due to age and usage. We extend the concept of minimal repair for the one‐dimensional case to the two‐dimensional case and characterize the failures over a two‐dimensional region under minimal repair. An application of this important result to a manufacturer's servicing costs for a two‐dimensional warranty policy is given and we compare the minimal repair strategy with the strategy of replacement of failure. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
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159.
本篇译稿节选了美国空军中校卡伦·O·杜尼文《军事文化——一个范式的转换?》一书的部分内容,作者考察了美国军事文化中的社会性变化,探究了美国军事文化中一种介于军事的传统与非传统之间的,介于男性战士为主的范式或信仰体系和以平等主义与兼容并蓄为特征的充满矛盾的进化军事文化模式之间的斗争。这是一场旧思想和新思想之间的竞赛。译者选编了作者战斗部队中的女性(战争中的女性)这一典型案例来阐述美国军事文化中范式与模式之间的差异。杜尼文中校在本书中还考察了美国军事文化中存在的长期冲突,她建议美国军方现在开始需再一次进行文化范式的转换———从传统的以男性士兵为主的排他性价值观向一种兼容并蓄的从军观念转变。作者强调美国军方必须在其发展过程中,削减其分离主义和排外性的倾向。她提出实施这一范式转换的三个对策(战略部署):改变军方的占主导地位的关于“战斗着的,充满阳刚之气”的具有排他性而非包容性的标准和想法;主动接受并控制正在持续的主要的社会性变化;同时接受与个人和组织对范式转换的职责。范式转换的先驱们必须特别地推崇一种兼容并蓄与平等主义的文化。杜尼文中校也强调了美国高级军事将领是产生美国军事范式转换的最佳催化剂———他们是真正的先驱,他们能够使兼容并蓄的文化范式制度化。杜尼文中校提出如下结论:如果美国希望其军方成为美国社会的一面镜子,无疑要接受一种兼容并蓄的文化范式。  相似文献   
160.
Since 2012, China’s assertion of its sovereignty claim to the contested Senkaku/Diaoyu Islands has significantly raised the risk of a potentially escalatory political-military crisis with Japan. As circumstances worsen, Japanese Prime Minister Shinzo Abe has championed major institutional reforms aimed at centralizing Japanese security policy decision-making and vastly improving crisis management. This article assesses these reforms’ significance for ameliorating Japan’s long-standing internal crisis management weaknesses, and enhancing its ability to communicate with Beijing promptly under challenging conditions. While significant issues remain, recent developments – especially the establishment of Japan’s first-ever National Security Council – demonstrate significant progress. Bilaterally, however, important firebreaks remain conspicuously absent.  相似文献   
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