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1.
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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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
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Nicholas G. Evans 《The Nonproliferation Review》2013,20(3-4):351-366
ABSTRACTScience and technology (S&T) review is key to anticipating developments in the life sciences that may benefit or run contrary to the aims of the 1972 Biological and Toxin Weapons Convention. It serves as a mechanism for both preparing against novel biological threats and identifying the best opportunities for developing and sharing the life sciences to the fullest extent. In the age of rapidly advancing biotechnology, S&T review needs to be wide ranging, involve a diverse set of inputs, and be transparent about its methods and data. This viewpoint considers four models of S&T review and their capacity to respond to the challenge of the life sciences: standing advisory boards; ad hoc working groups; peer review; and wikis. It then identifies a hybrid model that is suitably broad, diverse, and transparent. 相似文献
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摘要:针对单小批量武器装备保障的特殊需求,对传统的质量屋模型进行了改进,建立了基于装备保障需求与保障规则的质量屋模型,利用整数规划技术进行求解,使得单小批量武器的装备保障规则按照实际保障需求重新排列优先次序,并通过对某型火炮保障方案的筛选验证了模型的正确性.新的质量屋模型发展完善了质量屋的理论与方法,有助于提高单小批量武器的装备保障能力. 相似文献
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将软件设计中的面向对象思想扩展到系统设计中,针对柴油机实车运行在线监测中的变速变载及空间有限等问题,基于CAN总线的可靠性、信息传输的实时性和多主工作方式,设计分布式智能监测节点和上位机监控中心.分布式监测节点同步采集柴油机运行数据并进行降噪和简单特征提取后,将实时采样数据和在线监测结果上传至基于嵌入式PCI04的上位机监控中心,进行二次特征提取和智能模式识别,从而实现柴油机在线状态监测与故障预警和诊断. 相似文献