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101.
From the Editors     
Israel's policy of military reprisals has never seemed to follow any consistent pattern of tit‐for‐tat. On the one hand, not every violent incident was answered with a counterattack. On the other hand, when Israel responded, frequently it employed an excessive amount of force, which was disproportional to the Arab provocation. This behavior has not been the consequence of a premeditated and rational strategy. Instead, it appears to have been the result of a political dispute between alternative approaches regarding the use of military force. The following research analyzes the development of this controversy and how these differences of opinion were resolved.  相似文献   
102.
This paper systematically analyzes the causes of the escalation of violence during the initial stages of the Jeju Island Rebellion and the failure of South Korean counterinsurgency operations. It is argued that four interrelated factors provided the conditions for armed insurgency in the small island of Jeju: inter-agency tension between the Korean National Police (KNP) and the Korean Constabulary; the mainlanders' misinterpretation of the insurgency; the effect of systematic police brutality; and the role of youth groups. Consequently, two counterinsurgency lessons will be drawn from this study: that inter-agency cooperation and coordination at the tactical level between security branches and the incorporation of local population at the micro-level is essential in conducting efficient and effective counterinsurgency operations.  相似文献   
103.
燃烧加热型煤油加热器工作特性试验   总被引:2,自引:1,他引:1       下载免费PDF全文
针对冲压发动机地面试验应用需求,设计了基于燃气加热方式的煤油加热器,通过试验的方法研究了多个因素对其工作特性的影响规律。研究结果表明,该煤油加热器加热能力强,响应时间短,可在线制备超临界/裂解态煤油;其中,燃气温度、流量和煤油流量是影响煤油加热器工作特性的主要因素,通过控制燃气温度和流量可以大范围调节煤油温度,能满足冲压发动机不同试验工况的应用需求。  相似文献   
104.
针对HLA/RTI在接口规范、对象模型模板等关键技术建立分布式仿真平台的复杂性,提出了利用数字武器开发平台进行开发的方法,构建防区外空面导弹攻防对抗系统体系结构,实现了该体系结构联邦成员划分、设计联邦/仿真对象模型表等HLA仿真关键技术,并采用面向对象建模与仿真技术建立了各联邦成员的数学模型.该仿真结果表明,各联邦成员的数学模型与底层支撑环境能够相互分离,仿真模型具有良好的交互性和互操作性,可通过添加或删除联邦成员仿真不同的复杂战场想定,并可作为验证不同算例的仿真平台.  相似文献   
105.
The responses of AI/PTFE reactive materials (RMs) under shock compression were investigated by a single-stage gas gun.A 3D mesoscale-model was established based on micro-computed tomography(micro-CT) slice images and confirmed with experimental results.In the high-pressure stage,the com-posites reacted partially,whereas there were no deviations between the partially reacted Hugoniot and the inert simulation results.The simulation reveals that the Teflon matrix melting on the high shock pressure.Melts and decomposition of the PTFE accelerated the diffusion of the atoms.Thus,the reactions of the Al/PrFE composites are more like a combustion rather than a detonation.  相似文献   
106.
Building on prior work on optimal replacement of aging aircraft, this paper presents three methodologies to evaluate prospective aviation Service Life Extension Programs (SLEPs) and applies these methodologies to US Navy F/A-18E/F data. While considerable uncertainty remains as to the values of key parameters (e.g. the cost of F/A-18E/F SLEPs), the preponderance of the evidence available at this juncture favors undertaking SLEPs on F/A-18E/Fs rather than replacing them with new Joint Strike Fighters.  相似文献   
107.
基于有限元法(FEM)和光滑粒子流体动力学(SPH)结合的算法,用数值模拟了钢质弹丸对钢筒约束土体的侵彻过程。基于ANSYS/LS-DYNA显式动力分析和LS-PrePost后处理软件,形象再现了钢质弹丸冲击作用下土体飞溅形成漏斗坑和直线通道的物理过程。侵彻深度计算结果与实验数据吻合较好,钢质弹丸的速度和加速度时程曲线图与理论分析一致,体现了FEM/SPH算法的精确性。研究结果表明FEM/SPH算法在模拟侵彻土体方面具有可行性和有效性。  相似文献   
108.
以基于N2O/C7H8的燃烧驱动混合型气动CO2激光器点火试验为研究背景,设计了液态N2O供应系统及N2O/C7H8单喷嘴燃气发生器.对液态N2O供应系统、N2O/C7H8的点火及燃烧性能进行了研究.试验结果表明:设计的N2O供应系统能够实现液态N2O的稳定供应;在设定的时序下,两个设计工况(余氧系数分别为0.3和0....  相似文献   
109.
We consider preventive transshipments between two stores in a decentralized system with two demand subperiods. Replenishment orders are made before the first subperiod, and the stores may make transshipments to one another between the subperiods. We prove that the transshipment decision has a dominant strategy, called a control‐band conserving transfer policy, under which each store chooses a quantity to transship in or out that will keep its second‐subperiod starting inventory level within a range called a control band. We prove that the optimal replenishment policy is a threshold policy in which the threshold depends on the capacity level at the other store. Finally, we prove that there does not exist a transfer price that coordinates the decentralized supply chain. Our research also explains many of the differences between preventive and emergency transshipments, including differences in the optimal transfer policies and the existence or nonexistence of transfer prices that coordinate the system. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
110.
In this paper, a single‐machine scheduling problem with weighted earliness and tardiness penalties is considered. Idle time between two adjacent jobs is permitted and due dates of jobs could be unequal. The dominance rules are utilized to develop a relationship matrix, which allows a branch‐and‐bound algorithm to eliminate a high percentage of infeasible solutions. After combining this matrix with a branching strategy, a procedure to solve the problem is proposed. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 760–780, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10039  相似文献   
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