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151.
It is not too soon to draw cautionary lessons from the inconclusive results of US performance during more than 11 years of Operation ‘Enduring Freedom’ in Afghanistan. As in Vietnam, fundamental difficulties persist in adapting enduring institutions to the requirements of strategy. At the heart of the matter is tension between the assumptions that underlie counterinsurgency as practiced in Afghanistan and organization of the US Armed Forces, State Department, and Agency for International Development. Knowledge of basic principles and necessary changes is available to answer the question, could the US have done better?  相似文献   
152.
Given the nature of global counterinsurgency operations, the demands of military expansion, and the need for cultural, linguistic, and regional expertise, the United States Army should evaluate the establishment of US-led foreign troop units for its evolving force structure. This article proposes the creation of an American foreign legion based upon the recruitment of US-led, ethnically homogeneous tribal force units to meet the grist mill of counterinsurgency operations. This structured approach would be more beneficial than the current reliance on a de facto American Foreign Legion, represented by private military contractors (PMCs), many of them comprised of foreigners. These PMCs carry a number of oversight, accountability, and legal risks not found in a fully integrated, and US-officered foreign legion. The British Brigade of Gurkhas, the South-West African Police Counter-Insurgency Unit (Koevoet), and the Kit Carson Scouts serve as relevant historical examples where foreign troops were used to supplement national manpower resources.  相似文献   
153.
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   
154.
采用人工智能方法求解空间优化问题已成为当前地理学研究领域的热点之一。研究目的在于通过设计一个开放的、可扩展的人工免疫空间优化模型框架,开发基于插件技术的优化工具软件,丰富空间优化决策支持的方法和技术体系。研究从空间优化问题的基本特点和计算需求出发,定义了面向空间优化问题求解的克隆选择优化模型框架。在此基础上,采用"插件-宿主平台"结构设计了人工免疫智能空间优化平台的总体架构,定义免疫算子插件与空间优化问题应用插件开发机制。实验结果表明,平台的架构和功能设计充分考虑了计算平台的开放性和扩展性,通过平台标准接口的功能扩展可实现对不同类型空间优化问题的求解。空间优化问题研究者或政府决策部门无需关系人工免疫优化方法的具体内涵即可基于本平台完成其具体空间优化决策支持任务。  相似文献   
155.
设计了一种用于精密转台的新型自补偿圆锥形液体静压轴承,并完成了轴承的制造与性能测试。采用流量平衡原理推导了轴承设计公式,得到了轴向和径向的最优刚度及其优化条件,计入制造误差对轴承承载性能进行了仿真,并测试了轴承的刚度和回转精度。结果表明:轴承刚度受到节流间隙与承载间隙的流阻比以及油腔间内流系数影响,流阻比存在最优值,而内流系数越小,对刚度越有利;计入制造误差的仿真模型能够有效预测轴承刚度范围。  相似文献   
156.
无人机集群作战概念及关键技术分析   总被引:3,自引:0,他引:3  
无人机集群作战正在从概念走向雏形.文章总结了国外无人机集群作战概念的发展,分析了无人机集群作战的主要关键技术,包括大规模无人机管理与控制、多无人机自主编队飞行、集群感知与态势共享、集群突防与攻击、集群作战任务控制站等技术,并展望了未来无人机集群协同搜索、协同干扰、协同攻击、协同察/打、集群对抗等作战应用.  相似文献   
157.
This paper models transnational terrorism as a three‐way strategic interaction involving a government that faces armed opposition at home, which may spill over in the form of acts of terrorism by the state's opponents against the government's external sponsor. The external sponsor also utilises deterrence against potential terrorists, which only lowers terrorism if terrorists are not intrinsically motivated by a deep‐seated sense of humiliation. The model highlights the importance of intrinsic motivation. A rise in the external power's preference for deterrence against terrorism may backfire in these circumstances. Increases in the government's military efficiency against the rebels, who are also terrorists against the government's sponsor, raises overall levels of violence.  相似文献   
158.
This paper is intended to complement the existing literature on civil wars. First, it presents a simple theoretical model of conflict that defines a two‐sector economy. In a contested sector, two agents struggle to appropriate the maximum possible fraction of a contestable output. In an uncontested sector, they hold secure property rights over the production of some goods. Agents split their resource endowment between ‘butter’, ‘guns’ and ‘ice‐cream’. Following the theoretical insights the empirical analysis focuses on the relationship between civil wars and different sectors of the economy. In particular, a panel probit specification shows that the incidence of a civil war decreases in the size of manufacturing sector.  相似文献   
159.
油料洞库担负着我国未来石油储备的重要任务,为深入研究油料洞库在地震作用下的响应规律,运用FLAC3D软件,采用动力时程法对油料洞库的简化模型进行数值模拟分析。从不同围岩级别、不同埋深、不同地震烈度3个方面分析地震作用时水平峰值位移和最大拉应力峰值的变化规律。结果表明:随着围岩级别从Ⅲ级到Ⅰ级的变化以及埋深的增加,油料洞库的抗震性能逐渐提高;无论何种工况,最大拉应力峰值均发生在主罐室与支通道交接的墙角处;9度地震时各监测点水平峰值位移大幅增加,塑性区已经贯通,故在油料洞库选址时应尽可能避开可能发生9度及以上地震的地区。  相似文献   
160.
为深入了解内初班学生的学习适应性状况,本研究分别在石河子市四所内初班承办学校中,严格按照分层抽样的方法选取了294名学生作为被试,采用《学习适应性测验》量表探求内初班学生的学习适应性特征。结果显示:石河子内初班学生的学习适应性与全国常模基本一致,学习适应不良主要集中在学习技术和学习态度上。在性别上、年级上差异不显著,民考民和民考汉学生的学习适应性在全量表上差异显著,总体上民考民学生的学习适应性优于民考汉学生。  相似文献   
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