首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   13篇
  免费   0篇
  2020年   1篇
  2019年   1篇
  2017年   1篇
  2014年   2篇
  2013年   4篇
  2002年   2篇
  1997年   1篇
  1969年   1篇
排序方式: 共有13条查询结果,搜索用时 343 毫秒
1.
2.
3.
4.
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   
5.
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   
6.
7.
8.
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   
9.
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   
10.
This paper considers a three‐person rendezvous problem on the line which was introduced earlier by the authors. Three agents are placed at three consecutive integer value points on the real line, say 1, 2, and 3. Each agent is randomly faced towards the right or left. Agents are blind and have a maximum speed of 1. Their common aim is to gather at a common location as quickly as possible. The main result is the proof that a strategy given by V. Baston is the unique minimax strategy. Baston's strategy ensures a three way rendezvous in time at most 3.5 for any of the 3!23 = 48 possible initial configurations corresponding to positions and directions of each agent. A connection is established between the above rendezvous problem and a search problem of L. Thomas in which two parents search separately to find their lost child and then meet again. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 244–255, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10005  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号