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421.
基于有源诱偏原理,推导出反辐射导弹在有源诱偏条件下的弹落点计算公式;并由已知的导弹毁伤模型,利用计算机仿真获得对目标雷达或其有源诱饵的毁伤效能。通过仿真结果分析不同的攻击角和末速度对导弹毁伤效能的影响,由此获得反辐射导弹在干扰条件下的最佳攻击角和末速度范围,对于在诱偏条件下研究反辐射导弹毁伤能力的有效性和实用性提供一定的理论和实用参考。  相似文献   
422.
跟踪变形目标包括假定目标的全局运动和时间方程的局部变形。粒子滤波算法依靠参数化法选择,但是不能处理曲线的拓扑变化。活动轮廓模型是独立参数化,可以比较好地适应拓扑变化。基于上面两个方法的局限性,将上述两种方法相结合,运用于变形目标的跟踪。实验结果证明,该方法有很强的鲁棒性,对部分遮挡的物体有很强的适应性,证明了该方法的有效性。  相似文献   
423.
国外坦克装甲车辆主动防护系统   总被引:2,自引:0,他引:2  
从陆军装甲主动防护系统的产生、发展和应用进行了阐述;对陆军装甲主动防护系统的国际通用分类、应用现状及发展现状进行了分类介绍;就国际几种典型的陆军装甲主动防护系统进行了详细介绍;最后就陆军装甲主动防护系统进行了发展和应用前景的分析。  相似文献   
424.
为了对多波长激光主动式相干合成做出初步的理论描述,揭示影响合成效果的关键因素,根据相干合成的基本原理,建立了计算模型.并以9波长7路相干合成系统为实例,仿真计算了光程差取不同值的情况下,各频率成分的合成效果和总体合成效果.当各路间存在较大的光程差时,只有中心频率成分实现了相干相长,其他频率成分处于"混乱"状态,总体合成...  相似文献   
425.
分析Rayleigh信道下分集/无分集的AF( Amplify and Forward)和DF( Decode and Forward)模式单中继传输的平均中断概率,给出解析表达式.在总功率约束下推导了4种模式下的统计最优功率分配的解析表达式来最小化系统的平均中断概率,并提出通过最佳中继选择进一步降低系统的平均中断概率...  相似文献   
426.
目前,我国公安机关在处置群体性事件过程中,在警察权定位及适用权限判断上存在着警察权适用程序失准、绩效不足、角色失当、制度不完善等困境。应从明确公安机关的处置原则、角色定位、建立权力规制和权利救济制度、构建公安机关分级应对策略等方面加以完善。  相似文献   
427.
The world is mired in history again, as historical modes of competition return and historical grievances fuel the policies of multiple revisionist actors. If the end of history has ended, then it follows that the time is ripe for an engagement with history’s wisdom. We argue that the making of American statecraft—the deliberate, coordinated use of national power to achieve important objectives—can be significantly enhanced by a better understanding of the past. This essay, which draws on the extensive literature on history and statecraft, U.S. foreign policy, and the author’s own research and experiences, offers a defense of the use of history to improve statecraft, as well as a typology of ten distinct ways in which an understanding of history can improve government policy.  相似文献   
428.
A nation's structure and culture of civil-military relations are important and largely overlooked factors in explaining the performance of armed forces involved in complex expeditionary operations. The US model of ‘Huntingtonian’, divided civil-military structures and poor interagency cooperation, makes the US military less suited for complex expeditionary operations. British civil-military relations involve a Defence Ministry that conscientiously integrates military and civilian personnel, as well as extensive interagency cooperation and coordination. This ‘Janowitzean’, integrated form of civil-military relations makes the British military more likely to provide for the planning and implementation of comprehensive campaigns that employ and coordinate all instruments of power available to the state, as well as troops in the field displaying the flexibility and cultural and political understanding that are necessary in complex expeditionary operations.  相似文献   
429.
The story of the demise of Canada's remarkable CF-105 Arrow jet-fighter interceptor has been told and retold by numerous Canadian writers. As told by most, it is a tragic tale. Canadian Prime Minister John Diefenbaker, in an act as unforgivable as it was incomprehensible, not only destroyed a highly promising all-Canadian state-of-the-art aircraft but ruined all hopes of Canada ever being an important player in the North American defense industry. This article offers a contrasting interpretation — locating the problems leading to the aircraft's cancellation further back in history, and in particular in serious and determinative failures in strategic thinking and analysis by senior Canadian military officials at the time of the Arrow program's birth in 1953.  相似文献   
430.
In this article, we consider a problem in which two suppliers can sell their respective products both individually and together as a bundle, and study the impact of bundle pricing. Four pricing models (centralized, decentralized, coop–comp, and comp–coop) are analyzed with regard to the competition formats and sequences. As one would expect, the firms are always better off when pricing decisions are centralized. However, rather surprisingly, we find that firms may be worse off if the bundle prices are set in a cooperative way; we provide analytical characterization of those instances. Numerical studies show that these insights also hold for some nonlinear demand. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
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