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281.
采用量子粒子群求解声压和质点振速组成的非线性相关方程组,实现多目标声源方位的估计。为提高精度,应用最小二乘法对测量结果进行拟合并建立预测模型,通过卡尔曼滤波对方位轨迹进行优化。结果表明:单矢量水听器能够同时分辨多个目标方位,解算结果应使用统计特性表示;采用本方法最多能分辨7个目标,目标个数越多,方位误差越大;信噪比越高,分辨率和精度越高,偏差越小;通过数据拟合然后卡尔曼滤波的方法能够有效提高目标方位跟踪精度。 相似文献
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Thomas H. Johnson 《Small Wars & Insurgencies》2013,24(5-6):1006-1039
ABSTRACTThis article systematically assesses the 2014 Afghanistan Presidential Election, the first transfer of power from President Hamid Karzai to an elected successor, using provincial voting data as well as explicit data from polling centers. The analysis finds unusual voting results in the April election, where no candidate received 50%+1 votes required by the Afghan constitution, versus the voting results realized for the June ‘runoff election.’ As in other Afghan voting analyses, this article finds voting based on ethno-linguistic preferences, and interestingly found Dr. Ashraf Ghani receiving almost all the swing votes in the runoff election even though the other leading candidate from the April election all endorsed Dr. Abdullah Abdullah. More importantly, however, the research presented here clearly finds extremely strange voting patterns. For example, the polling data center analysis finds 606 polling places where Ghani received all 600 votes and Abdullah received none and another 900 polling centers that gave virtually all its votes to Ghani. These results in combination with other analyses raise the very real possibility that the election results were illegitimate. The article concludes with a discussion of the implications of the research to future Afghan elections and their processes as well as to the long-standing conflict in the country. 相似文献
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Riley M. Moore 《Small Wars & Insurgencies》2013,24(5):857-878
As a consequence of intervention in Iraq and Afghanistan, force ratio for counterinsurgency (COIN) has come under increased scrutiny. Reduced to its essence, the issue is simply, ‘How many troops does it take to get the job done?’ This answer has been sought by the US military, academia, and think tanks. There have been numerous responses, culminating in several ‘plug-and-play’ equations for minimum force ratios in COIN operations. Due to the impossibility of determining precisely how many insurgent forces there are, it has become common to base force ratios on the population of the country. In the realm of policy, the question above is posed as, ‘How many of our troops does it take to get the job done?’ 相似文献
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\"新三论\"(包括耗散结构论、协同学和突变论)作为一种新的世界观,给研究作战系统这个复杂的非线性系统提供了新的视角。运用\"新三论\"的思想和方法指出作战系统的序参量,建立序参量方程,分析序参量演化稳定性与途径,得出一些有价值的结论,对于探索作战系统发展演变的规律具有重要意义。 相似文献
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