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241.
In the absence, to date, of an exact method for solving the linear programming problem with fixed charges, two heuristic methods have been proposed and extensively investigated, computationally, for moderate sized problems. The results indicate that the heuristic methods produce optimal solutions in well over 90 percent of the several hundred problems investigated and very close to optimal (a few percent) in the remaining cases. Hence it should be of practical significance to practitioners in the field. 相似文献
242.
243.
本文以实验结果为依据,首先分析了塑料弹体影响弹丸膛内运动的物理性能,然后结合旋转弹丸的膛内运动特征,经过模拟试验,采用数学拟合法,初步建立旋转稳定弹塑料弹体工程设计计算的数学模型(包括结构尺寸设计计算、强度计算和内弹道计算)。 相似文献
244.
On-site verification of ICBMs in the context of an arms control agreement might involve a situation where an inspector would choose one or more of a number of identical areas to inspect and would have confidence that the other areas had the same characteristics. This article considers optimal attack and defense of missiles deceptively based in a number of identical areas. The attacker may allocate warheads across areas as he desires and uniformly within areas. The defender may allocate interceptors across areas as he desires and either uniformly or preferentially within areas. The effect of restricting the defender to uniform allocation across areas is explored for various assumptions. Robustness of surviving missiles with respect to the number of attacking warheads is studied. Results are presented for a wide range of cases. 相似文献
245.
A promising approach to failure modeling, in particular to developing failure-time distributions, is discussed. Under this approach, system state or wear and tear is modeled by an appropriately chosen random process—for example, a diffusion process—and the occurrences of fatal shocks are modeled by a Poisson process whose rate function is state dependent. The system is said to fail when either wear and tear accumulates beyond an acceptable or safe level or a fatal shock occurs. This approach has significant merit. First, it provides revealing new insights into most of the famous and frequently used lifetime distributions in reliability theory. Moreover, it suggests intuitively appealing ways for enhancing those standard models. Indeed, this approach provides a means of representing the underlying dynamics inherent in failure processes. Reasonable postulates for the dynamics of failure should lend credence to the prediction and estimation of reliability, maintainability, and availability. In other words, accuracy of representation could lead to better, more reliable prediction of failure. 相似文献
246.
Peter C. Fishburn 《海军后勤学研究》1967,14(1):1-13
A theory of additive utilities is discussed for cases where the set X, on which an individual's preference-indifference relation is defined, is a subset of the Cartesian product of n finite sets. A number of potential applications of additive utilities in decision making are presented. 相似文献
247.
Richard L. Russell 《战略研究杂志》2013,36(1):136-155
Some scholars counter-intuitively argue that the proliferation of nuclear weapons increases international security by substantially reducing the chances for inter-state armed conflict. This school of thought draws heavily on the history of the American-Soviet Cold War rivalry to inform its analysis. The security dilemmas in the contemporary Middle East and South Asia where numerous states have or want nuclear weapons, however, are profoundly different than the competition between the United States and the Soviet Union. States in the Middle East and South Asia today may see nuclear weapons as usable instruments of warfare in contrast to conventional wisdom in the West that views them as weapons of deterrence and last resort. As common sense would have it, American and Allied policy designed to stem the proliferation of nuclear weapons is prudent. American diplomatic intervention, moreover, in regional crises as a third party may be needed in the future in the Middle East and South Asia to lessen the risks of nuclear warfare. Nevertheless, American policy-makers are likely in the future to find themselves facing a nuclear-armed nation-state-or soon to be nuclear weapons-capable state-in a crisis and will have to grapple with the risks of pre-emptive or preventive military action. 相似文献
248.
Pakistan confronts numerous domestic security challenges including jihadist extremism, Sunni-Shi'a sectarian violence, drug trafficking, illegal commodity smuggling, endemic corruption, and systemic problems with the provision of justice and law enforcement. While much has been written about US military assistance to the Government of Pakistan (GOP) and the ever-evolving political relations between the two countries, basic questions of highest policy significance related to Pakistan's internal security have never been fully studied or considered. This essay begins to address these empirical lacunae. It first provides a comprehensive examination of Pakistan's internal security environment and the effectiveness of the GOP's criminal justice structures in dealing with these challenges. The paper then goes on to assess the impact and utility of the current suite of US law enforcement assistance in helping to fortify Pakistan's domestic security environment. The study raises a number of difficult questions pertinent to the long-term impact of this support, particularly in terms of its effect on fostering a viable, accountable and transparent system of civilian governance and policing. 相似文献
249.
O. Peter St. John 《Small Wars & Insurgencies》2013,24(2):196-219
Much of the literature on the decolonization of Namibia is set in a narrative mode and demonizes one or the other of the protagonists. This article, organized in a topical fashion, concerns the diplomatic, military, and economic facets of the Namibian war and draws upon the literature of comparable twentieth century colonial and anti-colonial wars in Algeria, Angola, Kenya, Mozambique, the Philippines, South Africa, Vietnam and Zimbabwe. It explores the changing discourse of legitimacy concerning independence for Namibia, the conduct of insurgency and counterinsurgency in the bush war, and economic aspects of that war. 相似文献
250.
Peter J. Lyth 《战略研究杂志》2013,36(2):230-238
Catherine Andreyev, Vlasov and the Russian Liberation Movement: Soviet Reality and Emigre Theories. Cambridge: Cambridge University Press, 1987. Pp.251; $34.50. Sergej Froehlich, General Wlassow: Russen und Deutsche zwischen Hitler und Stalin (revised and edited by Edel von Freier). Koeln: Markus Verlag, 1987. Pp.403; DM.39.80. Joachim Hoffmann, Die Geschichte der Wlassow‐Armes. Freiburg: Verlag Rombach, 1986. Pp.468; DM32. 相似文献