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21.
Matthew J. Thomas 《Small Wars & Insurgencies》2013,24(3):413-435
On 9 February 2012 the Somali terrorist organization al-Shabaab officially merged with al-Qaeda. While the significance of the merger is highly contested, it does expose internal weaknesses within the two organizations along ideological, clan, and sectarian lines. The article identifies three key weaknesses of the merger and concludes with a discussion of al-Qaeda's growing presence in trans-Saharan Africa. 相似文献
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Matthew S. Goldberg 《海军后勤学研究》1987,34(4):535-545
If material failures follow a Poisson distribution, then the expected number of failures is exactly proportional to flight hours. However, this article demonstrates that proportionality will not be revealed by simple correlation or regression analysis between monthly flight hours and the number of monthly failures. To test for proportionality, one must instead test the underlying hypothesis that the data follow a Poisson distribution. This article presents three simple tests that may be used for this purpose. The Poisson distribution requires that the mean and variance of the number of failures be equal. This article suggests several alternative models that may be used for samples in which the variance exceeds the mean. First, the mean of the Poisson distribution may itself be randomly distributed across the observational units according to a gamma distribution. If so, the number of failures will have a negative binomial distribution. Second, the mean of the Poisson distribution may depend systematically upon a set of observable explanatory variables. In this case, the Poisson regression model is appropriate. Finally, the mean of the Poisson distribution may contain both a systematic component that depends upon observable variables and a random component. This situation yields a generalized Poisson regression model. 相似文献
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The individual and social optimum control policies for entry to an M/M//1 queue serving several classes of customers have been shown to be control-limit policies. The technique of policy iteration provides the social optimum policy for such a queue in a straightforward manner. In this article, the problem of finding the optimal control policy for the M/Ek/1 system is solved, thereby expanding the potential applicability of the solutions developed. The Markovian nature of the queueing system is preserved by considering the service as having k sequential phases, each with independent, identically distributed, exponential service times, through which a customer must pass to be serviced. The optimal policy derived by policy iteration for such a system is likely to be difficult to use because it requires knowledge of the number of phases rather than customers in the system when an arrival occurs. To circumvent this difficulty, a heuristic is used to find a good usable (implementable) solution. In addition, a mixed-integer program is developed which yields the optimal implementable solution when solved. 相似文献
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Military Helicopters. By E. J. Everett‐Heath, G. M. Moss, A. W. Mowat and K. E. Reid. Brassey's, London (1990), ISBN 0–08–037341–0 (hardcover), ISBN 0–08–036716‐X (flexicover), £22.50 (hardcover), £12.95 (flexicover)
The Killing Ground: the British Army, the Western Front and the Emergence of Modern Warfare 1900–1918. By Tim Travers. Unwin‐Hyman, London (1990), ISBN 0–04–4457367, £11.95
The Influence of S. L. A. Marshall on the United States Army. By Major F. D. G. Williams. TRADOC Historical Monograph Series, Fort Monroe, VA (1990) 相似文献
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Matthew J. Morgan 《Small Wars & Insurgencies》2013,24(3):97-110
The controversy over banning landmines in the past decade has removed matters of military technical expertise to the purview of civilian interest groups. According to a Huntingtonian perspective, this could be an indicator of unhealthy civil-military relations. Evidence of this includes political leaders' disregard of senior military advice and the initiation of a program to develop landmine alternatives after having already committed to banning them. The desire to ban landmines may represent a pragmatic revision of pacifist attempts to ban warfare altogether. Because of the development of self-destructing or deactivating mines, the landmine ban movement intrudes on technical military matters without redeeming humanitarian value. This intrusion may have further ramifications for civil-military relations. 相似文献
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Matthew S. Seligmann 《战略研究杂志》2013,36(3):454-479
In the 1990s no-fly zones were introduced as a new way to utilize airpower in the context of Peace Support Operations (PSOs). During that time, they were put to use over Iraq and over Bosnia. However, it is unclear to what extent the no-fly zones were successful in those two instances. This article examines the capabilities of no-fly zones and analyzes the Iraq and Bosnia cases of enforcement. It concludes that no-fly zones can be very effective if properly implemented and offers guidance for policy-makers on how to achieve maximum efficacy. 相似文献
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Matthew S. Seligmann 《战略研究杂志》2013,36(2):114-147
This essay traces the image of Germany that emerges from the reports of Colonel Frederick Trench (1857–1942), British military attache in Berlin from 1906 to 1910. At this time, the British Army possessed only the most limited intelligence‐gathering apparatus and had to rely heavily on the reports of military attaches for information about their continental rivals. Trench, who believed that Germany planned to wage war against Britain and said so categorically in his reports, was the main source of data on the German Army. From the limited surviving records of who read these reports and how they responded to them, this essay posits that Trench's views contributed to the growing British perception of a German threat, a perception that did much to influence British strategic planning in this period. 相似文献
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Matthew Bunn 《The Nonproliferation Review》2013,20(3):533-538
Defusing Armageddon: Inside NEST, America's Secret Nuclear Bomb Squad, by Jeffrey T. Richelson. W.W. Norton & Company, 2009. 318 pages, $27.95. 相似文献