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71.
探讨了无人飞行器(UAV)编队的任务分配问题。任务分配是UAV协同控制的基础,其解是任务区域内各任务的一个排列。求解UAV任务分配问题的有效方法是能在合理的计算时间内找到近似最优解的启发式算法。用对称群描述UAV任务分配的搜索空间,基于右乘运算构造搜索邻域。仿真结果验证了群论禁忌搜索算法的有效性。  相似文献   
72.
Under quasi‐hyperbolic discounting, the valuation of a payoff falls relatively rapidly for earlier delay periods, but then falls more slowly for longer delay periods. When the salespersons with quasi‐hyperbolic discounting consider the product sale problem, they would exert less effort than their early plan, thus resulting in losses of future profit. We propose a winner‐takes‐all competition to alleviate the above time inconsistent behaviors of the salespersons, and allow the company to maximize its revenue by choosing an optimal bonus. To evaluate the effects of the competition scheme, we define the group time inconsistency degree of the salespersons, which measures the consequence of time inconsistent behaviors, and two welfare measures, the group welfare of the salespersons and the company revenue. We show that the competition always improves the group welfare and the company revenue as long as the company chooses to run the competition in the first place. However, the effect on group time inconsistency degree is mixed. When the optimal bonus is moderate (extreme high), the competition motivates (over‐motivates) the salesperson to work hard, thus alleviates (worsens) the time inconsistent behaviors. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 357–372, 2017  相似文献   
73.
During the period 1996–2006, the Communist Party of Nepal (Maoist) waged overt people’s war to seize state power and institute a new order that realized the party’s understanding of ‘New Democracy’ as posited by Mao Tse-tung. Contextual shifts led to a crucial strategic turning point in September 2005, when the Maoists agreed to a united front with estranged legal parties to oust the monarchy and establish a republic. Though touted as acceptance of political reintegration, the move was tactical rather than strategic. The party had no intention of supporting a parliamentary version of democracy and thus, 2006–2016, engaged in a covert effort to seize power. Central to this effort was the paramilitary Young Communist League (YCL), the members of which responded to inflammatory party verbiage and exhortations with attacks upon rival political actors. These attacks, academically and legally, were terrorism and offered a salient illustration of intra-state unrestricted warfare. Ultimately, organizational, national, and regional circumstances caused the main Maoist movement to move decisively away from its covert approach. By that time, however, radical splinters had embraced the use of terrorism against rival political actors, creating a situation whereby local politics is yet a dangerous endeavor in certain areas and at certain times.  相似文献   
74.
In his 1987 work Strategy: The Logic of War and Peace (Harvard University Press, Cambridge, MA, 1987), Edward Luttwak described strategy as a field of activity characterised not only by an innately complex relationship between designs, actions and outcomes, but so too by the frequent disparity between its theory and praxis. Similar observations on this subject have since been made by Richard K. Betts, Lawrence Freedman and Antulio Echevarria II. This article will use the Allied invasion of Sicily in July–August 1943 as a vehicle through which to test these theories against a signal event in the European theatre of the Second World War. It will illustrate how Operation Husky and its aftermath are a paradigm of the confusing and often illogical course of events associated with the process of formulating strategy and waging war. In so doing it demonstrates the benefits of using strategic theory to illuminate events and so move beyond the often insular focus of campaign histories, and simultaneously reinforces the importance of military history in informing a theoretical understanding of strategy.  相似文献   
75.
This article assesses Bernard Fall’s concept of Vietnamese Revolutionary Warfare in Indochina between 1953 and 1958. It also investigates differences in the conceptualization of Revolutionary Warfare between Fall and proponents of French military doctrine known as la guerre révolutionnaire. The last component of the article considers limits of Fall’s influence on counterinsurgency doctrine.  相似文献   
76.
Jacques Maritain (1882–1973) is widely recognized as one of the foremost Catholic philosophers of modern times. He wrote groundbreaking works in all branches of philosophy. For a period of about 10 years, beginning in 1933, he discussed matters relating to war and ethics. Writing initially about Gandhi, whose strategy of non-violence he sought to incorporate within a Christian conception of political action, Maritain proceeded to comment more specifically on the religious aspects of armed force in “On Holy War,” an essay about the civil war then ongoing in Spain (1936–1939). After the outbreak of World War II in September 1939, Maritain penned a series of essays that sought to explain why the Anglo–French declarations of war were warranted on Christian just war principles. While the secondary literature on Maritain’s thought is extensive, thus far there has been little systematic exploration of his writings on war. In what follows I seek to remedy this lacuna, by examining how he conceptualized just war in the three phases outlined above.  相似文献   
77.
Insurgencies thrive in regions where government legitimacy is absent. In the post-war Philippines, Captain Charles T. R. Bohannan of the Army’s Counter Intelligence Corps became actively aware of this dynamic. Bohannan is best known for his later work with Edward Lansdale and Ramon Magsaysay in defeating the Huk Rebellion (1950–1954). Here the author examines Bohannan’s early investigative work against Japanese war criminals, wartime Filipino collaborators, and the rising threat of communist subversion most associated with the Huk. All of these experiences fed into what would be the successful campaign against the Huk, chronicled in his seminal work, Counter Guerrilla Operations: The Philippines Experience, and offers lessons on the investigative (as opposed to tactical or psychological) nature of effective counter-insurgency work, as it relates to both legitimacy in governance and the rise of insurgencies.  相似文献   
78.
The paper explores terrorist choice by applying two well-known theoretical frameworks: stochastic dominance and prospect theory (PT). We analyse each pair of attack methods that can be formed from the RAND-MIPT database and the Global Terrorism Database. Instances of stochastic dominance are identified. PT orderings are computed. Attention is accorded to the identification of ‘trigger points’ and the circumstances that may lead to an increased likelihood that a terrorist will select an attack method associated with a higher expected number of fatalities, i.e. a potentially more damaging attack method.  相似文献   
79.
基于应变路径法和球孔扩张理论,结合真实源与虚拟源、真实源与虚拟汇的相互作用,在假定土体变形为小应变的前提下,将压入实心桩单桩挤土位移的求解方法应用于压入管桩,通过求解真实源与虚拟汇共同作用下产生的竖向挤土位移,并修正地表面处的附加剪应力,得到压入管桩单桩竖向挤土位移的解析解;通过求解真实源与虚拟源共同作用下产生的水平挤土位移,并修正地表面处的附加正应力,得到压入管桩单桩水平挤土位移的解析解。由挤土位移的解析解可知,桩长、管桩内外径和土塞高度最大值的变化都会对压入管桩挤土位移产生影响。  相似文献   
80.
三维均匀化理论预测多孔混凝土等效弹性模量   总被引:2,自引:0,他引:2  
应用多尺度渐进展开的均匀化理论,推导三维均匀化理论的有限元解法,求解复合材料等效弹性系数。假设多孔混凝土由光滑均匀一致的球孔与水泥石基质组成,提出改进的随机投放方法,生成三维均匀化理论求解的随机单胞模型。以聚苯乙烯泡沫(EPS)混凝土为数值算例,生成6组不同体积分数的EPS混凝土随机单胞模型,通过三维均匀化理论的有限元法计算得到其等效弹性模量。计算结果表明:随机单胞模型能反映细观的非均质性,三维均匀化理论的有限元法计算得到的等效弹性模量变化趋势比较符合Miled的试验结果。  相似文献   
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