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741.
D. J. White 《海军后勤学研究》1993,40(4):553-568
In this article we study the quadratic assignment problem by embedding the actual data in a data space which satisfies an extension of the metric triangle property. This leads to simpler computations for the determination of heuristic solutions. Bounds are given for the loss of optimality which such heuristic solutions would involve in any specific instance. © 1993 John Wiley & Sons, Inc. 相似文献
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Since 1975 “offsets” have begun to appear frequently in contracts covering international sales of aircraft and other products incorporating advanced technology. Offsets involve reciprocity beyond that normally found in an exchange of goods for money. They may involve co‐production or co‐design of the principal item to be exchanged, or acceptance by the seller of goods or services unrelated to it as partial payment (indirect offsets or countertrade). The United States has become the major provider of offsets and anti‐offset sentiment has grown. Economists interpret them as trade diverting. Politicians from regions suffering loss of employment view them as bestowing unfair advantage to foreign competitors. The authors examine offsets from both theoretical and policy perspectives and conclude that in such noncompetitive markets, second‐best considerations dominate, requiring case‐by‐case evaluation of impacts and rendering across‐the‐board determinations of welfare loss suspect. 相似文献
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B.K. GREENER-BARCHAM 《Small Wars & Insurgencies》2013,24(1):90-112
Some scholars would have us believe that the distinctions between military and policing roles, methods and objectives have become increasingly blurred by the security demands of a post-Cold War and post-11 September global and domestic order. This article explores the current state of the police–military divide through a conceptual and case study analysis. It concludes that, in this case, there is some conflation occurring at a macro-level as international and domestic affairs have become increasingly indistinct, but the article also demonstrates that the actual ethos and practice of these agencies still differs strongly. Most importantly, the article argues that this distinction is in fact a very useful one in planning for future peace support operations 相似文献
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Nathan A. Jennings 《Small Wars & Insurgencies》2013,24(2):313-334
This essay explores how federalized Texas Rangers, in the form of scout companies and larger mounted rifle regiments, provided controversial, and ultimately cost-effective, versatility to the US Army during its campaign in Northern Mexico between 1846 and 1848. It argues that their contributions centered on three tactical tasks that enhanced the invading army's maneuvers: reconnaissance, direct assault, and counterguerrilla patrolling. Each of these actions reflected a distinctive skill-set at which the auxiliaries excelled, marking them as exceptionally multifunctional assets. The Texans' augmentation coincided with, and was necessitated by, the evolving stages of the war in Northern Mexico, beginning with the American army's initial invasion, then transitioning to the assault on Monterrey, and finally ending with a troubled occupation where the rangers' brutality both enabled and undermined American pacification efforts. 相似文献
746.
Jeffrey S. Lantis 《The Nonproliferation Review》2013,20(2):389-409
The 2010 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) produced a Final Document calling for an extension of the principles of the nonproliferation norm as well as steps toward complete disarmament. This article looks beyond the rhetoric, however, to examine recent decisions by great powers to expand nuclear trade with non-NPT countries and the implications of these decisions on the traditional nonproliferation norm of restraint. This article seeks to contribute to constructivist theory by supplementing existing accounts of norm creation and establishment with a new model of norm change. The article develops a case study of the 2008 US-India nuclear deal to highlight the role of elite agency in key stages of norm change, including redefinition and constructive substitution through contestation. It concludes that the traditional nonproliferation norm may be evolving in new directions that are not well captured by existing theoretical frames. 相似文献
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Let X be a positive random variable. The distribution F of X is said to be “new better than used in expectation,” or “NBUE,” if E(X) ⩾ E(X – t|X > t) for all t ⩾ 0. Suppose X1, …, Xn, is a random sample from an NBUE distribution F. The problem of estimating F by a distribution which is itself NBUE is considered. The estimator Gn, defined as the NBUE distribution supported on the sample which minimizes the (sup norm) distance between the NBUE class and the empirical distribution function, is studied. The strong uniform consistency of Gn, is proven, and a numerical algorithm for obtaining Gn, is given. Our approach is applied to provide an estimate of the distribution of lifetime following the diagnosis of chronic granulocytic leukemia based on data from a National Cancer Institute study. 相似文献
750.
We consider the burglar problem in which a burglar can either retire or choose among different types of burglaries, with each type having its own success probability and reward distribution. Some general structural results are established and, in the case of exponentially distributed reward distributions, a solution technique is presented. The burglar problem's relationship to a stochastic knapsack problem with a random exponentially distributed knapsack capacity is shown. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 359–364, 2014 相似文献