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881.
分析AM波通过LC谐振放大器时的不失真条件,提出解决失真的办法.  相似文献   
882.
Clausewitz was much preoccupied with the apparent contradiction between real and absolute war. Why did war in history so rarely exhibit the extremes of violence and energy implied in the pure concept of war? Clausewitz’s commentators have usually followed him in thinking that this was a genuine problem in need of a solution, but I want to question that view. I will argue that Clausewitz did not have a coherent philosophy of absolute war, and therefore the contradiction he posited between real and absolute war was equally meaningless – as, too, was his effort to resolve it by claiming that some real wars approached or even attained the absolute form of war. The real problem was not the opposition of real and absolute war, but the self-contradictory theory of absolute war.  相似文献   
883.
The search continues for methods to improve security for development in Sub-Saharan Africa. One of the important actors in this security arena is Sub-Saharan African governments’ armies. Much of their capability to meet security challenge depends on how militarily professional they are. The wave of democratic evolution in Africa since 1990 also affected military professionalism. This article reviews three models for assessing how democratisation might affect military professionalism in Sub-Saharan Africa, with special attention to post-conflict states. This should make it possible to decide which analytical methods are most appropriate to measure military professionalism in the particular circumstances of Sub-Saharan African post-conflict democratisation. Depending upon the particular nation-state in question, this decision on analytical methods may be useful for other Sub-Saharan states as well.  相似文献   
884.
In June 2016, the Colombian Government and the FARC insurgent movement signed a ceasefire agreement, which brings the two sides one step closer to putting an end to over five decades of war. Unfortunately, Latin America has a rich history of insurgent movements, particularly during the cold war era, some of which continue to operate today. Most of these movements disappeared due to military operations, though some did so via peace negotiations. This essay aims to discuss the various ends of Latin American insurgencies to answer whether, indeed, insurgents can be negotiated with.  相似文献   
885.
Abstract

The Sahel has gained attention in international politics as one of the central theatres in the war on terrorism. International actors in this war seek alliances with states in the region, reinforcing the latter’s military strength and their legitimacy from outside. At the same time, increasingly-connected young populations question the legitimacy of their states, and contest that legitimacy from within and below. In the absence of states delivering any reasonable form of social contract, young people become torn between different governing orders and find themselves in a liminal space. In this article we present the cases of youth in Mali and Chad, who find themselves in a period of re-definition of their position in society and hence search for legitimate structures representation. In this search they may frame their belonging in terms of ethnicity, religion or political opposition – and increasingly also in adherence to global citizenship. New information flows and connectivity among young people in these regions, and between them and the diaspora, has given a new turn to their search for citizenship/belonging and rightful representation. However, whether their search will be successful in this geopolitical context is questionable.  相似文献   
886.
缩比模型试验是获取大型运载火箭动特性的一种有效途径,其中一项重要内容是动力学缩比模型设计。本文以某型运载火箭为原型对象,首先根据其结构组成分别推导各部件的相似关系;然后,利用横向刚度和质量相似系数保持一致性,联立形成了运载火箭横向动特性相似关系;同时,考虑实际加工制造条件,分析了横向刚度和质量相似系数的约束;最后,根据上述相似关系和相似系数约束设计了1/5缩比模型,并对该缩比模型的动特性相似进行了有限元数值计算验证。验证结果表明,设计所得1/5缩比模型在动特性方面与原型具有较高的相似性,相关方法能够有效应用于运载火箭的动力学缩比模型设计。  相似文献   
887.
针对动态多属性方案排序优选决策问题,提出了一种基于累积前景理论的时间矩阵序列动态多属性综合评判系统模型。依据累积前景理论,将时间矩阵序列动态多属性决策转化为关于属性期望的益损时间矩阵序列动态决策,综合考虑各属性权重、各时间点的权重,计算各方案的最终综合前景值,并依据其大小对方案进行综合评判排序。最后给出了一个决策实例。  相似文献   
888.
通信侦察过程积累了大量电台通信记录,对这些数据进行分析、推理,可以识别电台的数量、装载平台等,为了提高识别正确率,提出了基于灰关联分析和粗糙集的通信电台识别方法。首先,依据粗糙集理论将信息表划分等价类,得到电台航迹;再根据灰关联分析计算雷达航迹和电台航迹的灰关联度,最后按照最大灰关联度原则进行通信电台关联。实验结果表明该方法适用范围更广,在多个平台的运动轨迹交叉且在交叉时刻各有电台通联、同一平台上的多个电台在不同时间通联这两种情况下,均能较好地对电台进行关联。  相似文献   
889.
为探讨固支方形钢板结构在空爆冲击波和高速破片联合作用下的动态响应过程及变形破坏模式,利用有限元分析软件ANSYS/LS-DYNA,开展了空爆冲击波和高速破片对固支方板的联合作用数值模拟计算,阐述了固支方板在联合载荷作用下动态响应过程的2个阶段,以及在不同爆距下的变形破坏模式和特点。结果表明,随着爆距增加,在破片密集作用区内,钢板的破坏模式存在从集团冲塞破口到部分穿孔边界撕裂联通,再到无穿孔边界撕裂现象的转换。  相似文献   
890.
针对D-S证据理论在高冲突下失效的问题,在比较修正原始证据源和重新分配冲突两种方法的基础上,提出一种新的合成规则,新方法用可信度修正证据的同时,把全局冲突分为两部分,并依据"全局冲突在全局分配、局部冲突在局部分配"的原则对冲突进行细化分配。通过仿真分析,并与其他方法比较,新的合成方法能更好地融合冲突证据,收敛速度快,具有较强的抗干扰能力。  相似文献   
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