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Steve Carpenter 《Defense & Security Analysis》2014,30(3):283-295
The US strategy in Afghanistan has fallen short of neutralizing the insurgency that threatens the future stability. The primary insurgency's leadership council, the Quetta Shura, has effectively managed influence through a shadow government and superior tactics in recruiting marginalized tribal leaders, leading to a questionable outcome once Coalition forces withdraw in 2014. This article summarizes the threat posed by the Quetta Shura, coinciding with the deficiencies in the current US policy, and recommends a more viable strategy conducive to the current circumstances, based on historical and cultural precedence. Coalition forces have put a great amount of time, money, and effort into establishing a more stable Afghanistan. The USA needs a more aggressive strategy to counter the aspirations of the insurgency, thereby giving the Afghans the opportunity to further progress in the future. Under the current circumstances and policies, a peaceful transition after the Coalition withdrawal is becoming more unlikely. 相似文献
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Following the 11 September 2001 attacks, the US government increased its counterterrorism (CT) funding and created several Federal Agencies such as the Department of Homeland Security; Transportation Security Administration; and National Counterterrorism Center. Similarly, the 7 July 2005, London bombings also compelled the British government to increase its CT funding. These examples illustrate a phenomenon that when states experience terrorism, they dramatically increase public safety spending in order to reduce or eliminate the incidents of and casualties resulting from acts of terror. Using statistical data collected from 34 countries covering nine years, this article examines recent CT spending increases. Critically, the authors explore whether recent public safety expenditures can measurably reduce the number of domestic and international terrorist attacks. The implications of their findings should be salient for policy-makers’ assessments of their countries’ current CT strategies and policies concerning their respective Intelligence and Security Communities. 相似文献
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Terrorists could acquire nuclear weapons by using weapon-usable nuclear material that was stolen or otherwise diverted from legitimate authorities. Multiple well-documented seizures suggest the existence of a black market that draws on an unknown stock of weapon-usable nuclear material that is not under the control of authorities. We estimate the total amount of uncontrolled material based on publicly reported seizures and several different statistical methods and models. We estimate that 90 to 250 kilograms—sufficient for up to ten nuclear weapons—remain outside the control of legitimate authorities. While this estimate is subject to large uncertainties and potential bias, governments may have additional information about nuclear material seizures that could be used to improve estimates. 相似文献
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We address a single-machine scheduling problem in which penalties are assigned for early and tardy completion of jobs. These penalties are common in industrial settings where early job completion can cause the cash commitment to resources in a time frame earlier than needed, giving rise to early completion penalties. Tardiness penalties arise from a variety of sources, such as loss of customer goodwill, opportunity costs of lost sales, and direct cash penalties. Accounting for earliness cost makes the performance measure nonregular, and this nonregularity has apparently discouraged researchers from seeking solutions to this problem. We found that it is not much more difficult to design an enumerative search for this problem than it would be if the performance measure were regular. We present and demonstrate an efficient timetabling procedure which can be embedded in an enumerative algorithm allowing the search to be conducted over the domain of job permutations.© 1993 John Wiley & Sons, Inc. 相似文献
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Steve Alpern 《海军后勤学研究》2002,49(3):256-274
Two players are independently placed on a commonly labelled network X. They cannot see each other but wish to meet in least expected time. We consider continuous and discrete versions, in which they may move at unit speed or between adjacent distinct nodes, respectively. There are two versions of the problem (asymmetric or symmetric), depending on whether or not we allow the players to use different strategies. After obtaining some optimality conditions for general networks, we specialize to the interval and circle networks. In the first setting, we extend the work of J. V. Howard; in the second we prove a conjecture concerning the optimal symmetric strategy. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 256–274, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10011 相似文献