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941.
针对孤立脉冲群电磁超声系统信号特征容易被噪声淹没的问题,提出基于改进的非负矩阵分解(INMF)优选特征的支持向量机(SVM)方法.首先,用3种不同的方法提取高维特征;其次,用NMF方法实现特征降维,并保证降维结果的唯一性,避免对特征的直接选择;最后,应用支持向量机方法对降维特征进行分类.对孤立脉冲群电磁超声系统采集的4种信号特征进行提取、选择和分类,实验结果表明:INMF方法能有效提取微弱信号的特征,减少运算量,提高电磁超声系统特征采集的准确率. 相似文献
942.
从材料破坏机理与规律出发研究结构性土体工程的渐进破坏过程,是实际工程研究的重要方向。针对结构性土的变形特点和传统本构模型解决结构性土体工程渐进破坏过程的不足,采用作者以前提出的结构性土损伤本构模型对边坡工程算例的渐进破坏过程进行模拟分析。算例计算结果分析表明:边坡在破坏过程中会形成一个贯通剪切带,剪切带土体完全损伤;剪切带上方土体损伤相对较小,且有距离剪切带越远损伤越小的趋势;剪切带下方土体损伤也较小,主要因为开挖对其影响很小且处于稳定的坡体内。研究证明,运用结构性土损伤本构模型能较好地解决实际工程损伤破坏问题。 相似文献
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可能性决策能较好地应对军事领域常常出现的概率难以获得,或者强调“出奇制胜”而有意规避概率风险的情形,是解决知识不完备情况下敌对行动预测的有力手段。从可能性理论基本公理体系出发,结合动态规划方法,提出并证明可能性决策的最优化定理,给出多步条件下可能性决策的实现算法,结合危机条件下敌对行动预测的范例和仿真分析,与传统概率风险决策进行比较,体现可能性决策的优越性,为该方法的推广应用创造条件。 相似文献
946.
在声纳搜索水雷任务中,为提高剩余雷数估计的准确性,加强作战辅助决策能力,针对现有评估模型未考虑漏搜区和重叠区,评估结果误差和离散性较大的问题,提出一种修正发现雷数的方法:对任务区建立网格,根据记录航迹获得的覆盖次数分布情况,从中提取出漏搜信息,并用其修正发现雷数向量。该方法有效解决了评估向量误差大、维数偏低的缺陷,显著提高了合理性。对典型情况的大量仿真试验证明,该方法能大幅度提高评估结果的准确性,降低离散性,并具有更强的适应性。 相似文献
947.
Quint Hoekstra 《Small Wars & Insurgencies》2013,24(5-6):981-1005
ABSTRACTState support for foreign rebel groups has become more salient, yet it remains unclear how this affects armed conflict. This paper therefore analyses the effect of foreign government assistance and does so in the typical case of the Angolan War (1975–1991). It argues that South African and United States support greatly helped the National Union for the Total Independence of Angola (UNITA) wage a large and sustained insurgency campaign but was ultimately insufficient to overthrow the People’s Movement for the Liberation of Angola (MPLA) government because it enabled the incumbent government to obtain similar foreign assistance and because the level of aid awarded to UNITA fluctuated strongly, preventing it from engaging in meaningful long-term planning. 相似文献
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Mustafa Cosar Unal 《Small Wars & Insurgencies》2013,24(3):432-455
The PKK has been a prolonged problem in Turkey, and various measures have been adopted to diminish and end the violence. In addition to the impacts on violence, these policies have also had an impact on public opinion and ethnic awareness of Kurds in Turkey. This article analyzes these policies and their effects on electoral support for the PKK by examining the vote shares of the pro-PKK political parties in national and local elections. It concludes that Turkey has conceptualized the issue solely as a problem of terrorism, but the goal, strategy, organization, and format of violence used by the PKK reflect the nature of an insurgency. Therefore, it is argued that Turkey, by ignoring the insurgency features, has disregarded the legitimate parts of the cause and related popular support, and thus has responded mostly with deterrent measures apart from the reforms of recent years. Results have shown that policies of deterrence culminated in a steady level of support for the PKK indicating that low level of legitimacy – as they were perceived by the people – of the policies resulted in viable popular and political support for the PKK. Despite the recent accommodative reforms, the existence of pro-PKK parties rallying electoral support in the political arena provided sustained level activities in the conventional politics in Turkey's municipal and national political system, in which they pursue pro-PKK agendas, such as ‘Autonomy’ and ‘Confederation’ as well as activities to increase the distinction in identity around the ethnic consciousness for more popular support. Yet, no clear pattern is identified between violence level and popular support in the macro-scale. 相似文献