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181.
本文利用微分对策方法研究了单兵种对多兵种作战时的最优火力分配原则,指出了应首先集中力量攻击敌方交战强度最大的一类作战单位。本文还说明了多兵种对多兵种作战时类似的问题的重要性和困难所在。  相似文献   
182.
为了对对角小跑中四足机器人本体的水平位置进行控制,建立基于沿支撑线方向运动分解的机器人近似动力学模型,将本体和对角支撑腿简化为一个七连杆结构和一个线性倒立摆,并且基于线性倒立摆解析模型提出摆动腿落足点位置计算方法,进而实现对本体水平位置的控制。针对液压作动器伸缩速度受限的问题,利用单腿冗余关节将关节角速度优化问题转化为标准二次型规划问题,通过设计二次型规划问题解法,降低对摆动腿关节角速度的需求,并且避免了传统伪逆方法可能产生的腿部奇异位型。仿真和实验结果表明:该方法能够实现在关节角速度受限的情况下,有效跟踪本体水平位置的期望轨迹。  相似文献   
183.
为了研究运动副间隙对空间4R机构动态特性的影响,间隙处的接触碰撞模型和摩擦的建立分别采用非线性弹簧阻尼模型和修正的库伦摩擦模型。在Solidworks中建立空间4R机构模型,导入ADAMS中进行动力学仿真分析。对比含间隙和不含间隙时系统动力学仿真结果的异同,分析间隙大小和最佳间隙量对空间4R机构动态特性的影响,为机构的设计提供了重要的参考依据,有利于工程实际应用。  相似文献   
184.
Counterterrorism operations in Kenya have often been hindered by a lack of collaboration, coordination and cooperation among the security agencies involved in such operations. This article examines the relationship between neo-elitism and counterterrorism security interagency activity in Kenya. Using neo-elitism as a framework for analysis, with specific reference to the September 2013 Westgate Mall attack counterterrorism operation, it is argued that the lack of collaboration, coordination and cooperation among Kenya’s counterterrorism security agencies often results in unintended adverse consequences. The interagency conflict over the Westgate operation was primarily about command and control, intelligence sharing and official information shared with the public pertaining to the stages of the siege and operation. These security agencies share similar responsibilities and jurisdictions in the rest of the country’s counterterrorism efforts. The interagency conflicts reveal that the country’s security elites pursue personal and agency-specific interests that are aimed at maintaining organisational supremacy over counterterrorism efforts. Recommendations are offered for how to tackle the problem of interagency conflict in order to enhance the effectiveness of counterterrorism operations in Kenya.  相似文献   
185.
This essay recalls the immediate and longer-term responses of the US and its allies to the events of 9/11. It contends that the die for contemporary developments in transnational terrorism was cast in the immediate aftermath of 9/11 – in particular the launching of sustained ‘anti-terrorist’ military combat operations in Afghanistan and Iraq, and more covert ‘kinetic’ operations elsewhere in the Middle East and Africa. The essay seeks specifically to expose the counter-productivity of using military operations as the primary antidote to transnational terrorism. Focusing on the African ‘laboratory’ and the spread of transnational terrorism and Islamic militancy, particularly in West and East Africa, the essay concludes that radical Islamists have mastered the ‘battle of the narrative’ and that the Western penchant for dispensing a kinetic brand of medication is feeding rather than fighting the virus of global terrorism.  相似文献   
186.
NATO burden sharing has become an especially timely issue in the past several years as a result of a number of factors, including Russian annexation of Crimea and destabilization of eastern Ukraine in 2014. This article argues that alliance unity among the great democracies of Europe and North America is indispensable to peace and stability on the Eurasian continent. A fractured NATO, and especially, a large divide in purposes or commitments as between the United States and its European security partners, invites aggression and the possibility of inadvertent escalation. Past successes and failures in US-involved multinational peace and stability operations, within and outside of Europe, show that mission accomplishment requires give and take, including the occasional acceptance of unequal costs and benefits among the members, in order to achieve peace and security objectives.  相似文献   
187.
肖龙  王坤林  潘晓刚 《国防科技》2017,38(3):108-111
研究联合作战自同步指挥问题。本文从自同步指挥的概念入手,阐述了自同步指挥的特点、实现基础和运行机理,分析自同步指挥的应用与发展前景。  相似文献   
188.
This paper considers a warehouse sizing problem whose objective is to minimize the total cost of ordering, holding, and warehousing of inventory. Unlike typical economic lot sizing models, the warehousing cost structure examined here is not the simple unit rate type, but rather a more realistic step function of the warehouse space to be acquired. In the cases when only one type of stock‐keeping unit (SKU) is warehoused, or when multiple SKUs are warehoused, but, with separable inventory costs, closed form solutions are obtained for the optimal warehouse size. For the case of multi‐SKUs with joint inventory replenishment cost, a heuristic with a provable performance bound of 94% is provided. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 299–312, 2001  相似文献   
189.
基于SuperMap的战区油料保障系统设计与实现   总被引:1,自引:1,他引:0  
通过对SuperMap与战区油料保障的结合,研究了基于SuperMap的战区油料保障系统,充分利用信息时代的成果提高油料保障的效能。分析了建立基于GIS的战区油料保障系统的必要性,全面构建了基于SuperMap的战区油料保障任务的数学模型,提出了未来信息化油料保障的可能途径,系统的设计并实现了基于SuperMap的战区油料保障系统,从而达到优化油料保障环节,缩短油料保障时间,提高油料保障透明度的目标。  相似文献   
190.
蔡军  于小红 《国防科技》2018,39(3):105-109
网络空间越来越被世界各国公认为是继陆地、海洋、空中和太空之后的第五个作战域,为获得和保持像其它作战域那样世界领先的军事优势,美国正在大力进行网络空间作战能力建设。提出了美国网络空间作战能力建设框架,从战略规划、作战力量、作战理论、作战训练、武器装备、战场基础环境、人才培养和作战联盟八个方面全面总结了美国近年来在网络空间作战能力建设方面的主要做法。  相似文献   
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