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471.
472.
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   
473.
    
In the years since the 2003 Rose Revolution, the popularly elected leadership of the Republic of Georgia has responded to organized protests with a variety of repressive tactics. These reactions suggest that former challengers to authoritarian elites may utilize similar methods of retaining power during crisis periods. Yet, the alleged involvement of agencies of the Russian Federation in fomenting domestic instability has also occupied a central position in the national security policies of the outgoing Saakashvili government. These conditions both preceded and were reinforced by the South Ossetia War of August 2008. This article proposes a theoretical model that represents the intervening effect of interstate conflicts on state–society relations in Georgia from 2003 to present. It presents several hypotheses and possible indicators, data sources, and techniques for analyzing the interaction between characteristics of opposition groups, external threats, and the domestic security practices of contemporary Georgian political elites.  相似文献   
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476.
From 2006 to 2011, al-Qaeda's East African proxy, al-Shabaab, served as the de facto ruling party of Somalia despite the efforts of the internationally recognised Transitional Federal Government (TFG). During these five years, a violent struggle between al-Shabaab and the peacekeeping force of the African Union Mission in Somalia (AMISOM) resulted in thousands of dead civilians, hundreds of thousands of internally displaced persons and a strategic environment inhospitable to reconciliation, recovery or development. By 2012, AMISOM was able to break the deadlock and force al-Shabaab from Mogadishu and Kismayo. In order to continue the momentum, the African Union and other partner nations must support the TFG in neutralising al-Shabaab throughout Somalia and providing good governance to its constituents. Al-Shabaab's revenue streams must be shut down and its offensive capability must be degraded while the strategic environment is shaped to ensure that conditions conducive to a revival do not exist. Failure to do so will likely see Somalia continuing to produce Islamist extremists and pirates to menace international maritime traffic in the western Indian Ocean, destabilise East Africa and adversely impact millions.  相似文献   
477.
A national recycling and waste management company provides periodic services to its customers from over 160 service centers. The services are performed periodically in units of weeks over a planning horizon. The number of truck‐hours allocated to this effort is determined by the maximum weekly workload during the planning horizon. Therefore, minimizing the maximum weekly workload results in minimum operating expenses. The perfectly periodic service scheduling (PPSS) problem is defined based on the practices of the company. It is shown that the PPSS problem is strongly NP‐hard. Attempts to solve large instances by using an integer programming formulation are unsuccessful. Therefore, greedy BestFit heuristics with three different sorting schemes are designed and tested for six real‐world PPSS instances and 80 randomly generated data files. The heuristics provide effective solutions that are within 2% of optimality on average. When the best found BestFit schedules are compared with the existing schedules, it is shown that operational costs are reduced by 18% on average. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 59: 160–171, 2012  相似文献   
478.
对潜搜索模型有很多种,并且这些搜索模型可能因为进一部的完善、优化而发生改变;根据装备的发展及部队作战、训练的需要,也可能有新的模型不断加入。这些模型的作战效果指标是决定其是否可用的重要依据之一,而作战效果的计算应基于统一的方法,而不能各自不同,这样,得出的结论才具有可比性。为了实现这个目的,建立了基于蒙特卡罗法的通用计算搜索效率指标的仿真算法原理和计算步骤,并给出基于该样式的实际应用例子。  相似文献   
479.
It is shown that two recent results of Baxter and Harche [1] on monotone and balanced optimal assemblies hold only under conditions that are more restrictive than those originally proposed by the authors. We describe such additional conditions, illustrate why they are needed, and establish their sufficiency. We also consider a recent result by Malon [11] and demonstrate that, while the result itself is correct, its two proofs were incomplete. A complete proof of an extension of the result is then suggested. © 1995 John Wiley & Sons, Inc.  相似文献   
480.
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