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281.
Christopher Kinsey 《Small Wars & Insurgencies》2013,24(4):584-614
This article sets out to investigate the impact of Private Security Companies (PSCs)1 on civil wars. In doing so, it has taken an historical line, outlining the way the industry has developed from when it first emerged on the international stage in the late 1960s, to the present. Importantly, the article is able to identify three broad strands of involvement in civil wars that include substituting for state military forces, propping up weak governments, and supplementing state militaries. Moreover, in each of these situations, the involvement of PSCs raises both moral and legal questions, as well as challenges for government. This is especially so in light of their activities in Iraq and Afghanistan and the likelihood that governments will increasingly turn to them for niche capabilities. 相似文献
282.
Kenneth M Pollack Dr 《战略研究杂志》2013,36(3):471-503
In the aftermath of Israel's stunning victory over Egyptian, Jordanian and Syrian forces during the 1967 Six-Day War, accolades for the victory were often showered upon the Israeli Air Force (IAF). Indeed, many believed that it had been Israeli air power that had been the decisive element in the war by first eliminating the Arab air forces and then obliterating the Arab armies in turn. While the IAF did play an extremely important role in the fighting, it was not the decisive element of Israeli victory, and its impact was felt in very different ways from the common perception. Indeed, an appreciation of the true role of Israeli air power in the war reinforces both the importance of psychological factors in combat, and the ability of air forces to have a psychological impact disproportionate to their physical impact. 相似文献
283.
We propose an algorithm for generating normal random variates that is based on the acceptance–rejection method and uses a piecewise majorizing function. The piecewise function has 2048 equal‐area pieces, 2046 of which are constant, and the two extreme pieces are curves that majorize the tails. The proposed algorithm has not only good performance from correlation induction perspective, but also works well from a speed perspective. It is faster than the inversion method by Odeh and Evans and most other methods. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
284.
Hassan M. Kamara 《Defense & Security Analysis》2015,31(3):260-269
The extensive timespan of evolving assumptions about future adversaries, US military engagements, and technology inherent in the US Army's 30-year modernization strategy can overwhelm the management capacity of planners, and misdirect acquisition investments. Some military scholars have argued that long-range planning is futile due to the complexities of the global security environment. So how can the US Army manage the evolving assumptions inherent in its 30-year modernization strategy to ensure it remains a superior global force? This study will answer the above question by arguing that the US Army's 30-year modernization strategy, while emulative of a similar modernization approach in the threat-based planning environment of the Cold War, is viable if supported by a method and a tool that manage investments and planning assumptions. 相似文献
285.
Factor screening is performed to eliminate unimportant factors so that the remaining important factors can be more thoroughly studied in later experiments. Controlled sequential bifurcation (CSB) and controlled sequential factorial design (CSFD) are two new screening methods for discrete‐event simulations. Both methods use hypothesis testing procedures to control the Type I Error and power of the screening results. The scenarios for which each method is most efficient are complementary. This study proposes a two‐stage hybrid approach that combines CSFD and an improved CSB called CSB‐X. In Phase 1, a prescreening procedure will estimate each effect and determine whether CSB‐X or CSFD will be used for further screening. In Phase 2, CSB‐X and CSFD are performed separately based on the assignment of Phase 1. The new method usually has the same error control as CSB‐X and CSFD. The efficiency, on the other hand, is usually much better than either component method. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
286.
There are n boxes with box i having a quota value Balls arrive sequentially, with each ball having a binary vector attached to it, with the interpretation being that if Xi = 1 then that ball is eligible to be put in box i. A ball's vector is revealed when it arrives and the ball can be put in any alive box for which it is eligible, where a box is said to be alive if it has not yet met its quota. Assuming that the components of a vector are independent, we are interested in the policy that minimizes, either stochastically or in expectation, the number of balls that need arrive until all boxes have met their quotas. © 2014 Wiley Periodicals, Inc. 62:23–31, 2015 相似文献
287.
We present methods for optimizing generation and storage decisions in an electricity network with multiple unreliable generators, each colocated with one energy storage unit (e.g., battery), and multiple loads under power flow constraints. Our model chooses the amount of energy produced by each generator and the amount of energy stored in each battery in every time period in order to minimize power generation and storage costs when each generator faces stochastic Markovian supply disruptions. This problem cannot be optimized easily using stochastic programming and/or dynamic programming approaches. Therefore, in this study, we present several heuristic methods to find an approximate optimal solution for this system. Each heuristic involves decomposing the network into several single‐generator, single‐battery, multiload systems and solving them optimally using dynamic programming, then obtaining a solution for the original problem by recombining. We discuss the computational performance of the proposed heuristics as well as insights gained from the models. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 493–511, 2015 相似文献
288.
M. Amarjeet Singh 《Small Wars & Insurgencies》2013,24(5):795-812
Soon after India attained its independence from British colonial administration in 1947 the Nagas started waging an armed conflict against India to establish a sovereign independent state in Nagaland in the country's Northeast region. The conflict is today one of the world's longer running and little known armed conflicts. India's central government has tried unsuccessfully to tackle the problem through political reconciliation, use of force, and several development measures. Over the years, it has also undergone several changes in which the situation of conflict deepened whenever India's central government intervened. And yet, the road ahead also faces severe challenges because the demand for bringing the Nagas of India together into a single political entity will not go unchallenged from other ethnic groups. Moreover, a bitter leadership battle divides the Naga rebels and hence any future agreement is likely to be difficult due to factional politics as have happened in the past. Thus one way to satisfy the aspirations of different ethnic groups while protecting the boundaries of the existing states in India is to explore the option of cultural autonomy. This idea is not entirely new, but has lost significance over the years. 相似文献
289.
290.
AbstractWe study the differential impacts of combat and humanitarian assistance/disaster relief (HA/DR) missions on the mental health of U.S. Marine Corps members. The deployment experiences of any individual Marine are plausibly random conditional on the observable characteristics which are used to assign Marines into units. Leveraging this exogenous variation, we compare the incidence of post-traumatic stress disorder (PTSD) and suicide deaths among Marines who deployed to either Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) or HA/DR missions between 2001 and 2011. We find that the hazard of PTSD is close to eight times higher among Marines returning from OEF/OIF compared to those never deployed, and just 1.33 times higher among those returning from HA/DR (and never participated in OEF/OIF). Those returning from OEF/OIF missions are 1.81 times more likely than those never deployed to die by suicide when they were still active duty, and the hazard increases to almost 3 after they have left the military. In contrast, we find no difference in the hazards of suicide death between those that deployed to only HA/DR missions and non-deployed Marines. 相似文献