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1.
运用树网结构可以完成矩阵的并行快速求逆,其中迭代法是一种非常重要的方法。本文给出了一种新的迭代格式,对任意非奇异矩阵A,运用新的迭代格式对A求逆相对于经典牛顿迭代法,在同样精度要求下,时间可减少一半。 相似文献
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提出了一种模糊方向神经网络分类器,并应用于液体推进剂火箭发动机故障检测与分离。模糊方向神经网络采用模糊集表示发动机故障模式,模糊集是方向超体聚集形成的集合体,方向超体则由单位方向、夹角和两个半径确定。模糊方向神经网络能在一次循环学习中形成非线性方向边界。故障检测与分离的仿真研究表明:模糊方向神经网络的识别性能是比较优越的。 相似文献
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蔡放 《国防科技大学学报》1994,16(4):102-105
论证了F为收缩算子时,求解X=F(X)的异步迭代方法初值选取范围,提出了异步迭代的大范围收敛方法。 相似文献
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Gabor变换和K-means算法是最为常用的纹理分析方法。然而,采用Gabor变换得到的纹理特征向量具有较高的维数,影响算法的运行效率;K-means算法也易受初始类中心的影响而导致分类精度下降。因此,通过Relief算法对采用Gabor变换所提取的纹理特征进行选择,得到合适的纹理特征子集。进一步采用差分进化算法,对K-means算法的聚类中心进行优化从而提高纹理识别精度和效率。实验结果表明:提出的方法所需用到的纹理特征向量的维数相对于原始特征集有大幅降低,较之基本的K-means算法,纹理识别的精度也有较明显的提高。 相似文献
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Nathaniel L. Moir 《Small Wars & Insurgencies》2017,28(6):909-946
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
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NOEL STOTT 《African Security Review》2013,22(3):4-11
A truly universal ban on anti-personnel mines cannot be realized without engagement of armed non-state actors and armed groups operating outside state control, including rebels and national liberation movements. Events after 9/11 have complicated engagement with organizations that can be classified as ‘terrorists’. Yet, the use of anti-personnel landmines itself can be viewed as an act of terrorism and African leaders have, on various occasions, classified the use of landmines and the presence of unexploded ordnance as engendering insecurity and a serious impediment to development. The success of a total ban ultimately depends upon ensuring that armed non-state actors act in accordance with international humanitarian law. The Geneva Call Deed of Commitment for Adherence to a Total Ban on Anti-Personnel Mines and for Cooperation in Mine Action (DoC) might be described as an alternative instrument to the Anti-Personnel Mine Ban Convention and can serve an important and impartial channel of communication with non-state actors. Already 18 armed groups in Africa have signed the Geneva Call DoC. 相似文献
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Peter Gastrow 《African Security Review》2013,22(1):39-43
This article discusses the validity of national security threats in Botswana and whether they justified the creation of the Directorate of Intelligence and Security Services (DISS), which has been controversial since its formation. Since its inception in 2008, the DISS has been accused of many human rights violations and politicisation. Without fully deliberating on the basis for its creation, some discourses have focused on the politicised operations without relation to what the DISS is supposed to be doing. The author works under the assumption that debates should be shaped by whether it was necessary to create the DISS, and, if so, how we can shape and steer debates on its oversight, management, reform and operations. This article argues that despite the politicisation of the DISS, Botswana's national security threats are both real and imagined; and that domestic threats to national security have moved from the conceptual ‘imagined’ category to the ‘real’. However, that in itself did not warrant the design and mandate of the DISS, and the article argues that it was external threats that really warranted the creation of a civilian intelligence agency. The article concludes that Botswana faces a plethora of external security threats – traditional and non-traditional – that warranted the creation and continuance of the DISS. 相似文献