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351.
William Rosenau 《Small Wars & Insurgencies》2013,24(3):65-99
US foreign internal security assistance, that is, support to ‘Free World’ governments threatened by subversion, terrorism, and insurgency, formed a central part of the Kennedy administration's strategy for defeating ‘wars of national liberation’. As part of the administration's counterinsurgency policy, support to police and paramilitary forces abroad was intended to improve the ability of friendly governments to identify and root our perceived threats to the states. Under the tenets of modernization theory embraced by administration officials, strong internal security forces were expected to contribute to nation-building by protecting the fragile development process underway in the developing world. However, in attempting to export the American police model, policymakers failed to consider whether US notions about internal security were appropriate for fractious and unstable regions of the world. 相似文献
352.
Over the past several decades, NATO allies have debated the relative burdens and benefits of NATO membership. Recently, this concern surfaced as members debated the magnitude and distribution of NATO expansion costs. This paper presents an economic model of defence alliances to identify the benefits and burdens of alliance membership. It suggests that defence expenditures provide public benefits if alliance members share common interests and mutual commitment; defence expenditures provide private benefits if countries lack common interests and mutual commitment. The model's results are used to discuss NATO's evolving roles and missions, NATO expansion and burden sharing across NATO members. 相似文献
353.
Abstract What are the consequences of military strikes against nuclear facilities? In particular, do they ‘work’ by delaying the target states ability to build the bomb? This article addresses these questions by conducting an analysis of 16 attacks against nuclear facilities from 1942 to 2007. We analyze strikes that occurred during peacetime and raids that took place in the context of an ongoing interstate war. The findings indicate that strikes are neither as uniformly fruitless as the skeptics would suggest, nor as productive as advocates have claimed. There is evidence that the peacetime attacks delayed the target's nuclear program, although the size of this effect is rather modest. The wartime cases were less successful, as attacks often missed their targets either due to operational failure or limited intelligence on the location of critical targets. In our concluding section we show that many of the conditions that were conducive to past success are not present in the contemporary Iran case. Overall, our findings reveal an interesting paradox. The historical cases that have successfully delayed proliferation are those when the attacking state struck well before a nuclear threat was imminent. Yet, this also happens to be when strikes are the least legitimate under international law, meaning that attacking under these conditions is most likely to elicit international censure. 相似文献
354.
Steven E. Lobell 《战略研究杂志》2013,36(6):747-773
This article challenges the conventional wisdom that Neville Chamberlain rejected the British tradition of balance of power in the 1930s. In contrast to balance of power and balance of threat theories, states do not balance against aggregate or net shifts in power. Instead, leaders define threats based on particular elements of a foreign state's power. The import is that different components of power of a foreign state are more or less threatening and aggregate shifts in power alone may not provoke counterbalancing behavior. In the 1930s, Britain balanced against the most threatening components of power: the German Luftwaffe and the threat of a knock-out air assault against the homeland, Japan's Imperial Navy and its threat to Britain's commercial trade routes and the Dominions in East Asia, and the Italian Navy and the threat to Britain's line of communication through the Mediterranean Sea to India and Asia. Given Britain's difficult financial circumstances, all other components of power, such as the army and the land components of power of Germany, Japan, and Italy were ranked as secondary in terms of its rearmament priorities. Thus, London was able to narrow the gap with Berlin in specific components of power of strategic importance such as aircraft production or to exceed Germany in other areas such as the Royal Navy and its battlefleet. 相似文献
355.
Jacques E. C. Hymans 《战略研究杂志》2013,36(5):769-797
Most historical accounts of the atomic bombings of Japan show little interest in Britain's explicit authorization for the attacks. Meanwhile, the few historians who have attempted to explain it rely on a unitary, rational actor model of the British state that is misleading. This article demonstrates that high-ranking British officials became anxious early on about the strategic consequences of a peremptory use of the new weapon. Therefore, especially over the course of 1944 they sought to engage Washington on the linked questions of the bomb's wartime use and its postwar control. However, these officials' initiatives were rebuffed by Prime Minister Winston Churchill, who paved the way to the bombings based on a fervent desire for Anglo-American integration, and on a dim understanding of the bomb's revolutionary potential. 相似文献
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358.
Passenger prescreening is a critical component of aviation security systems. This paper introduces the Multilevel Allocation Problem (MAP), which models the screening of passengers and baggage in a multilevel aviation security system. A passenger is screened by one of several classes, each of which corresponds to a set of procedures using security screening devices, where passengers are differentiated by their perceived risk levels. Each class is defined in terms of its fixed cost (the overhead costs), its marginal cost (the additional cost to screen a passenger), and its security level. The objective of MAP is to assign each passenger to a class such that the total security is maximized subject to passenger assignments and budget constraints. This paper shows that MAP is NP‐hard and introduces a Greedy heuristic that obtains approximate solutions to MAP that use no more than two classes. Examples are constructed using data extracted from the Official Airline Guide. Analysis of the examples suggests that fewer security classes for passenger screening may be more effective and that using passenger risk information can lead to more effective security screening strategies. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
359.
Approximation schemes for single‐machine scheduling with a fixed maintenance activity to minimize the total amount of late work 下载免费PDF全文
We consider the problem of scheduling n independent and simultaneously available jobs without preemption on a single machine, where the machine has a fixed maintenance activity. The objective is to find the optimal job sequence to minimize the total amount of late work, where the late work of a job is the amount of processing of the job that is performed after its due date. We first discuss the approximability of the problem. We then develop two pseudo‐polynomial dynamic programming algorithms and a fully polynomial‐time approximation scheme for the problem. Finally, we conduct extensive numerical studies to evaluate the performance of the proposed algorithms. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 172–183, 2016 相似文献
360.
Algorithm to solve a chance‐constrained network capacity design problem with stochastic demands and finite support 下载免费PDF全文
Kathryn M. Schumacher Richard Li‐Yang Chen Amy E.M. Cohn Jeremy Castaing 《海军后勤学研究》2016,63(3):236-246
We consider the problem of determining the capacity to assign to each arc in a given network, subject to uncertainty in the supply and/or demand of each node. This design problem underlies many real‐world applications, such as the design of power transmission and telecommunications networks. We first consider the case where a set of supply/demand scenarios are provided, and we must determine the minimum‐cost set of arc capacities such that a feasible flow exists for each scenario. We briefly review existing theoretical approaches to solving this problem and explore implementation strategies to reduce run times. With this as a foundation, our primary focus is on a chance‐constrained version of the problem in which α% of the scenarios must be feasible under the chosen capacity, where α is a user‐defined parameter and the specific scenarios to be satisfied are not predetermined. We describe an algorithm which utilizes a separation routine for identifying violated cut‐sets which can solve the problem to optimality, and we present computational results. We also present a novel greedy algorithm, our primary contribution, which can be used to solve for a high quality heuristic solution. We present computational analysis to evaluate the performance of our proposed approaches. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 236–246, 2016 相似文献