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31.
There is often a perception put forth of a fight for supremacy between China and the USA. This is often the case when discussing the continent of Africa. Both countries have recently increased their involvement in Africa for a variety of reasons. In 2011, China surpassed the USA as Africa's largest trading partner, with Africa predicted to be Beijing's largest trading partner by 2017. As expected, their bilateral and multilateral defence cooperation with strategic countries and organisations has matured and expanded along with it. Washington's own economic interests, al-Qa'ida and threats to maritime security are some of the crucial elements behind the US's presence on the continent. This article analyses both the USA and China's rising defence involvement in Africa. It compares and contrasts their similarities and differences, and argues that cooperation in certain areas can prove beneficial for all parties involved.  相似文献   
32.
Many studies of terrorism explain the use of violence against civilians with political or economic forces, often relegating social variables to the margins. Social factors, specifically societal-level social capital, play a far more important role in explaining patterns of terrorist activity than previously recognized. Social capital can exert pressures that act as both restraint and catalyst for terrorism, making explicit exposition of these differential effects critical. Analysis shows that higher stocks of social capital positively correlate with the number of terrorist groups, but the average attack activity of those groups increase as measures of social capital decline. The complex relationship makes it difficult to draw simple policy implications, but it does offer insight into the role that social dynamics play in terrorist activity.  相似文献   
33.
We consider the problem of safely and swiftly navigating through a spatial arrangement of potential hazard detections in which each detection has associated with it a probability that the detection is indeed a true hazard. When in close proximity to a detection, we assume the ability—for a cost—to determine whether or not the hazard is real. Our approach to this problem involves a new object, the random disambiguation path (RDP), which is a curve‐valued random variable parametrized by a binary tree with particular properties. We prove an admissibility result showing that there is positive probability that the use of an RDP reduces the expected traversal length compared to the conventional shortest zero‐risk path, and we introduce a practically computable additive‐constant approximation to the optimal RDP. The theoretical considerations are complemented by simulation and example. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005  相似文献   
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The United States’ Air Force (USAF) has developed and used unmanned aerial vehicle (UAV) technology to monitor and assassinate dangerous terrorists in Afghanistan, Iraq, Libya, Pakistan, Somalia, Syria, and Yemen. Currently, there are few countries that possess armed UAV and since the US created much of this technology, the USAF is usually part of the training that automatically accompanies the purchase of its UAVs. The research question this article attempts to answer is, “What is the extent of the United States’ Air Force assistance in the training and proliferation of UAV technology to foreign militaries?”  相似文献   
36.
The U.S. Navy Prowler aircraft is designed for electronic surveillance and countermeasures. In this paper, we describe the problem of scheduling Prowler crew training, and we present two integer programming models to solve it. The first model maximizes the number of aviators trained above 75% in each mission area, subject to the available number of flights, over a single month. The second model distinguishes peacetime from mobilization, and minimizes the number of flights done in mobilization subject to the available number of flights in peacetime. Our models distinguish different types of crew and allow more than one qualification to be earned on a given flight. We give numerical results using real data, comparing our results to the actual readiness of a squadron. We found that crew readiness of Prowler squadrons can be increased by 10%, simply by better scheduling. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 289–305, 2003.  相似文献   
37.
BUSTING OUT     
This report explores Iranian popular opinion on the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and the determinants of Iranian attitudes. Using data from a 2008 survey of 710 Iranians administered by the University of Maryland's Program on International Policy Attitudes, we find that that a significant minority of Iranians (10 percent in 2006 and 14 percent in 2008) would prefer that Iran withdraw from the NPT. Our statistical analysis shows that Iranians who fear a US attack on Iranian nuclear facilities and distrust the International Atomic Energy Agency are more likely to want to quit the NPT. We therefore argue that those who do not trust other nations are most likely to oppose the NPT.  相似文献   
38.
This essay reviews seven recent books and reports that focus upon the use of US armed drones in Pakistan's Federally Administered Tribal Areas (FATA). This essay synthesizes a historical account of the program, critically interrogates key arguments and evidence advanced by the authors, and draws attention the particular problems that confront those who live in the FATA and the second-class citizenship that the Pakistani state has bestowed upon them for reasons of domestic and foreign policy concerns. This review essay does not intend to be the final word on any of the ongoing policy debates. But it does hope to enable a wider audience to take part in these important deliberations.  相似文献   
39.
The reoptimization procedure within the shifting bottleneck (SB) involves reevaluation of all previously scheduled toolgroup subproblems at each iteration of the SB heuristic. A real options analysis (ROA) model is developed to value the option to reoptimize in the SB heuristic, such that reoptimization only occurs when it is most likely to lead to a schedule with a lower objective function. To date, all ROA models have sought to value options financially (i.e., in terms of monetary value). The ROA model developed in this paper is completely original in that it has absolutely no monetary basis. The ROA methodologies presented are shown to greatly outperform both full and no reoptimization approaches with respect to both computation time and total weighted tardiness. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
40.
This article describes and presents some results of the analysis of a queueing process where the degree of service given to a customer is subject to control by the management. The control doctrine used is based on the queue length and also on the recent history of the system.  相似文献   
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