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241.
The current nuclear nonproliferation order is no longer sustainable. The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) has weakened considerably over the years, with nuclear have-nots displaying increased dissatisfaction with the status quo. Meanwhile, demands for civilian nuclear technology have led to increased proliferation risks in the form of dual-use technologies. Arms control as we currently understand it—piecemeal treaties and agreements—is no longer sufficient to address the growing threat of proliferation and the frailty of the NPT. This article calls for a bolder nonproliferation agenda pursuing multilateral nuclear disarmament. Disarmament is, in fact, technologically achievable; a lack of political will stands as the only remaining roadblock to a world free of nuclear weapons. A better understanding of the technological feasibility of disarmament, as well as recognition of the diminishing strategic value of nuclear weapons, will help to erode this political reluctance.  相似文献   
242.
This paper discusses how crises and war may “disrupt” company activities, and how companies adapt to these disruptions. Croatia is used as a case study. The original hypothesis was that war led to breaks in physical flows: in other words, that companies experienced difficulties in importing and obtaining supplies of goods. Instead, it appears that loss of customers and severely worsened conditions of payment were the principal problems for Croatian companies. Although it does not fall within the scope of this investigation, it is interesting to note that the Croatian government has not imposed any direct rationing on the industrial sector, but rather via the banking system.  相似文献   
243.
There are n boxes with box i having a quota value Balls arrive sequentially, with each ball having a binary vector attached to it, with the interpretation being that if Xi = 1 then that ball is eligible to be put in box i. A ball's vector is revealed when it arrives and the ball can be put in any alive box for which it is eligible, where a box is said to be alive if it has not yet met its quota. Assuming that the components of a vector are independent, we are interested in the policy that minimizes, either stochastically or in expectation, the number of balls that need arrive until all boxes have met their quotas. © 2014 Wiley Periodicals, Inc. 62:23–31, 2015  相似文献   
244.
245.
We present methods for optimizing generation and storage decisions in an electricity network with multiple unreliable generators, each colocated with one energy storage unit (e.g., battery), and multiple loads under power flow constraints. Our model chooses the amount of energy produced by each generator and the amount of energy stored in each battery in every time period in order to minimize power generation and storage costs when each generator faces stochastic Markovian supply disruptions. This problem cannot be optimized easily using stochastic programming and/or dynamic programming approaches. Therefore, in this study, we present several heuristic methods to find an approximate optimal solution for this system. Each heuristic involves decomposing the network into several single‐generator, single‐battery, multiload systems and solving them optimally using dynamic programming, then obtaining a solution for the original problem by recombining. We discuss the computational performance of the proposed heuristics as well as insights gained from the models. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 493–511, 2015  相似文献   
246.
The extensive timespan of evolving assumptions about future adversaries, US military engagements, and technology inherent in the US Army's 30-year modernization strategy can overwhelm the management capacity of planners, and misdirect acquisition investments. Some military scholars have argued that long-range planning is futile due to the complexities of the global security environment. So how can the US Army manage the evolving assumptions inherent in its 30-year modernization strategy to ensure it remains a superior global force? This study will answer the above question by arguing that the US Army's 30-year modernization strategy, while emulative of a similar modernization approach in the threat-based planning environment of the Cold War, is viable if supported by a method and a tool that manage investments and planning assumptions.  相似文献   
247.
This paper presents several models for the location of facilities subject to congestion. Motivated by applications to locating servers in communication networks and automatic teller machines in bank systems, these models are developed for situations in which immobile service facilities are congested by stochastic demand originating from nearby customer locations. We consider this problem from three different perspectives, that of (i) the service provider (wishing to limit costs of setup and operating servers), (ii) the customers (wishing to limit costs of accessing and waiting for service), and (iii) both the service provider and the customers combined. In all cases, a minimum level of service quality is ensured by imposing an upper bound on the server utilization rate at a service facility. The latter two perspectives also incorporate queueing delay costs as part of the objective. Some cases are amenable to an optimal solution. For those cases that are more challenging, we either propose heuristic procedures to find good solutions or establish equivalence to other well‐studied facility location problems. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
248.
Adopting the analytical framework of the established interpretive “schools” of Anglo-American relations, this article offers several reflections on UK–US defense relations as they occurred over the significant years of 2000–2005. During those years, trajectories were established on which UK–US defense relations continue to travel today and outcomes emerged which are still being navigated. This article concludes that the Latin phrase, “Flectas Non Frangas” (essentially translated as: “Bend not Break”), is the most appropriate to adopt to characterize the developments undergone in recent UK–US defense relations. Many historical and strategic lessons with contemporary relevance are drawn.  相似文献   
249.
We propose an algorithm for generating normal random variates that is based on the acceptance–rejection method and uses a piecewise majorizing function. The piecewise function has 2048 equal‐area pieces, 2046 of which are constant, and the two extreme pieces are curves that majorize the tails. The proposed algorithm has not only good performance from correlation induction perspective, but also works well from a speed perspective. It is faster than the inversion method by Odeh and Evans and most other methods. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
250.
The 2003 conflict between Iraq and the US-led Coalition resulted in liberation for the country, enabling its citizens to experience freedom they have not had for decades. While the US-led operation was successful, insurgent movements have hindered the reconstruction efforts and the rebuilding of the government in Iraq. The tactics used by these insurgent groups are not that of 'traditional' warfare, therefore the US and Coalition forces adapted their tactics to respond to this new threat. It is argued that with the application of the Manwaring Paradigm (also known as the SWORD Model), the US and Coalition forces successfully responded to the insurgent movements during the period leading up to the Iraqi elections in January 2005.  相似文献   
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