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Britain's failure to cut military commitments in spite of escalating defence costs was not the result of blocking policies by disgruntled services. Rather, there was no determination among Whitehall's political departments to cut commitments even before the service departments could obstruct a decision on force levels. The Conservative governments under Macmillan and Douglas‐Home showed a propensity for substantial force reductions in Europe rather than in out‐of NATO areas. This remained London's long‐term aim even after it had been accepted to build up British troops in Europe to agreed force levels. During Alec Douglas‐Home's premiership Britain's global military role, especially east of Suez, gained a greater significance. An Anglo‐American military axis operating in the Far East and the Indian Ocean became a prominent feature. Ultimately, Anglo‐American military interdependence outside NATO was to ensure that Britain would be able to pursue a policy with more room for independent action.  相似文献   
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Dying to Win is one of the most important works on suicide terrorism. It purports to unravel the strategic, social, and individual logic that gives suicide terrorism its coercive value. The methodology that Pape uses to support his various assertions is problematic for three reasons. First, he defines his key terms in such a way as to artificially set suicide terrorism apart from other forms of political violence. Second, in a number of cases Pape selects data from single sources to support particular assertions when other sources of data, used together, could provide more rigorous and useful insights into the phenomenon of suicide bombing. Finally, Pape codes his data on suicide attacks according to a loose set of criteria which, if recoded, calls into question some of his broader conclusions about the strategic utility of suicide terrorism campaigns.  相似文献   
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History teaches that counterinsurgency and counterterrorism campaigns have never been won through purely military action. Defeating an opponent who avoids open battle, but who uses force to reach his goals, including terrorist action, requires a combination of police, administrative, economic and military measures. As a counterinsurgency campaign should pursue a comprehensive political objective, it requires high levels of civil–military cooperation. However, current NATO doctrine for Civil–Military Cooperation (CIMIC) as it emerged from the 1990s is founded in conventional war-fighting and outdated peacekeeping doctrine. CIMIC's focus is on supporting military objectives rather than enabling the military to make a coherent contribution to political objectives. This makes CIMIC unfit for the Alliance's main operational challenges that have expanded from peace operations on the Balkans to countering insurgent terrorism in Afghanistan. When developing CIMIC, the Alliance obviously neglected the historical lessons from counterinsurgency campaigns.  相似文献   
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深度学习容易被对抗样本所攻击。以通信调制识别为例,在待传输的通信信号中加入对抗性扰动,可以有效防止非合作的用户利用深度学习方法识别信号的调制方式,进而提升通信安全。针对现有对抗样本生成技术难以满足自适应和实时性的问题,通过对数据集中抽取的小部分数据产生的对抗扰动进行主成分分析,得到适用于整个数据集的通用对抗扰动。通用对抗扰动的计算可以在离线条件下进行,然后实时添加到待发射的信号中,可以满足通信的实时性要求,实现降低非合作方调制识别准确率的目的。实验结果表明该方法相对基线方法具有更优的欺骗性能。  相似文献   
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A rule that constrains decision‐makers is enforced by an inspector who is supplied with a fixed level of inspection resources—inspection personnel, equipment, or time. How should the inspector distribute its inspection resources over several independent inspectees? What minimum level of resources is required to deter all violations? Optimal enforcement problems occur in many contexts; the motivating application for this study is the role of the International Atomic Energy Agency in support of the Treaty on the Non‐Proliferation of Nuclear Weapons. Using game‐theoretic models, the resource level adequate for deterrence is characterized in a two‐inspectee problem with inspections that are imperfect in the sense that violations can be missed. Detection functions, or probabilities of detecting a violation, are assumed to be increasing in inspection resources, permitting optimal allocations over inspectees to be described both in general and in special cases. When detection functions are convex, inspection effort should be concentrated on one inspectee chosen at random, but when they are concave it should be spread deterministicly over the inspectees. Our analysis provides guidance for the design of arms‐control verification operations, and implies that a priori constraints on the distribution of inspection effort can result in significant inefficiencies. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
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We consider a generalization of the well‐known generalized assignment problem (GAP) over discrete time periods encompassed within a finite planning horizon. The resulting model, MultiGAP, addresses the assignment of tasks to agents within each time period, with the attendant single‐period assignment costs and agent‐capacity constraint requirements, in conjunction with transition costs arising between any two consecutive periods in which a task is reassigned to a different agent. As is the case for its single‐period antecedent, MultiGAP offers a robust tool for modeling a wide range of capacity planning problems occurring within supply chain management. We provide two formulations for MultiGAP and establish that the second (alternative) formulation provides a tighter bound. We define a Lagrangian relaxation‐based heuristic as well as a branch‐and‐bound algorithm for MultiGAP. Computational experience with the heuristic and branch‐and‐bound algorithm on over 2500 test problems is reported. The Lagrangian heuristic consistently generates high‐quality and in many cases near‐optimal solutions. The branch‐and‐bound algorithm is also seen to constitute an effective means for solving to optimality MultiGAP problems of reasonable size. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012  相似文献   
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