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161.
The current approach to countering the threat of improvised explosive devices (IEDs) in Afghanistan has met with limited success. The relative lack of success may be in part because the current approach is not holistic and discounts the social systems that foster the IEDs. Insurgents are using IEDs as a tool to further their strategic aims, but the coalition and to a lesser extent the Government of the Islamic Republic of Afghanistan (GIRoA) are attacking the IEDs as if they are an end in and of themselves. Combining network disruption with information change maximizes the opportunities for mitigating the IED threat. More specifically, to mitigate the IED threat requires disrupting the social and economic systems associated with IEDs, and at the same time providing alternative economic opportunities and improving rule of law and governance at the local level. In other words, counter-IED (C-IED) must be Counter-Insurgency (COIN) centric to be successful. This paper reviews the current state of C-IED efforts, identifies five main problems with the current approach, and suggests changes to reduce or mitigate the IED threat in Afghanistan.  相似文献   
162.
The British provided unprecedented shelter, training and supplies that made possible the revival of a new and better Belgian Army after the crushing German victories in 1940. Starting in Wales in 1940 as a small and disunited group, the Belgians improved more than any of the Allied exile ground forces. By 1944, their independent brigade fought well in Normandy and Belgium, restoring national pride and proving the worth of British help. The parallel and interdependent processes between the British and their Continental guests allows this analysis of the Anglo‐Belgian experience to be useful in considering British Army interactions with the other exiles as well.  相似文献   
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164.
Etzioni both exaggerates and minimizes the influence of my book Learning to Eat Soup with a Knife on different components of US military doctrine, mischaracterizes my treatment of the Malayan Emergency, and unfairly denigrates the successes of counterinsurgency in Iraq from 2007 to 2011 while misattributing the reasons for its failures in both Iraq and Afghanistan.  相似文献   
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166.
The second session of the Preparatory Committee for the 2015 Review Conference (RevCon) of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) highlighted two issues in particular—progress toward a Middle East Weapons of Mass Destruction–Free Zone and the Joint Statement on the humanitarian impact of nuclear weapons—that may not only greatly affect the health and vitality of the NPT and the 2015 RevCon, but possibly also have implications for the international nonproliferation regime as a whole. Dr. William Potter, director of the James Martin Center for Nonproliferation Studies, interviewed Ambassador Cornel Feruta, chairman of the 2013 PrepCom, to discuss these and other issues related to the meeting and the future of the treaty and its review process.  相似文献   
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168.
Multi-echelon logistic systems are essential parts of the service support function of high technology firms. The combination of technological developments and competitive pressures has led to the development of services systems with a unique set of characteristics. These characteristics include (1) low demand probabilities: (2) high cost items; (3) complex echelon structures; (4) existence of pooling mechanisms among stocking locations at the same echelon level; (5) high priority for service, which is often expressed in terms of response time service levels for product groups of items: (6) scrapping of failed parts; and (7) recycling of issued stock due to diagnostic use. This article develops a comprehensive model of a stochastic, multi-echelon inventory system that takes account of the above characteristics. Solutions to the constrained optimization problem are found using a branch and bound procedure. The results of applying this procedure to a spare parts inventory system for a computer manufacturer have led to a number of important policy conclusions.  相似文献   
169.
This article presents a branch and bound method for solving the problem of minimizing a separable concave function over a convex polyhedral set where the variables are restricted to be integer valued. Computational results are reported.  相似文献   
170.
We consider the problem of rescheduling n jobs to minimize the makespan on m parallel identical processors when m changes value. We show this problem to be NP-hard in general. Call a list schedule totally optimal if it is optimal for all m = 1, …,n. When n is less than 6, there always exists a totally optimal schedule, but for n ≥ 6 this can fail. We show that an exact solution is less robust than the largest processing time first (LPT) heuristic and discuss implications for polynomial approximation schemes and hierarchical planning models.  相似文献   
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