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201.
Martin Thomas 《战略研究杂志》2013,36(2):172-198
Unlike France, Britain viewed the Algerian conflict from 1958 to 1962 primarily as a colonial war. The British government regarded Algérie française as an anachronism, which France would have to relinquish one day. Though Britain was no stranger to ‘dirty’ colonial wars, as simultaneous operations against EOKA nationalists in Cyprus continued to prove, it was not averse to displaying a certain smugness at having averted the kind of mess Algeria seemed to represent. Britain's interest in the latter stages of the Algerian conflict centred on four major areas: Perceptions of colonial warfare; de Gaulle's Algeria policy; Algeria and Britain's view of France in Europe and NATO; Negotiating the ceasefire and ending the conflict. 相似文献
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This paper examines whether non-lethal weapons (NLWs) enhance the capability of the US armed forces to conduct irregular warfare (IW) operations. With expectations that the operational environment will only continue to become more complex in the future, NLWs may reduce the level of violence received, as well as dispensed, by US forces while performing tasks in the IW spectrum. We argue that NLWs increase the ability of US forces to address the long tail of warfare and their deployment should be increased in the near term. 相似文献
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In this article we introduce a 2‐machine flowshop with processing flexibility. Two processing modes are available for each task: namely, processing by the designated processor, and processing simultaneously by both processors. The objective studied is makespan minimization. This production environment is encountered in repetitive manufacturing shops equipped with processors that have the flexibility to execute orders either individually or in coordination. In the latter case, the product designer exploits processing synergies between two processors so as to execute a particular task much faster than a dedicated processor. This type of flowshop environment is also encountered in labor‐intensive assembly lines where products moving downstream can be processed either in the designated assembly stations or by pulling together the work teams of adjacent stations. This scheduling problem requires determining the mode of operation of each task, and the subsequent scheduling that preserves the flowshop constraints. We show that the problem is ordinary NP‐complete and obtain an optimal solution using a dynamic programming algorithm with considerable computational requirements for medium and large problems. Then, we present a number of dynamic programming relaxations and analyze their worst‐case error performance. Finally, we present a polynomial time heuristic with worst‐case error performance comparable to that of the dynamic programming relaxations. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
207.
为实现空中机动单站对运动目标的快速无源定位,提出了一种基于测向交叉定位方法的混合粒子滤波算法.针对粒子滤波初始化存在的问题,该算法从测向交叉定位方法得到建议分布,利用角度测量对状态变量的约束关系产生所需粒子,避免了粒子滤波产生粒子时的随机性,减少了高维情况下所需的粒子数目,降低了运算成本,提高了粒子滤波的实时性能.与粒... 相似文献
208.
在对自主车辆进行运动学分析的基础上,结合反应式行为规划方法和昆虫利用触角进行避障行走的思想,提出了一种使用圆弧形虚拟触角进行运动规划算法,并规划出在各圆弧轨迹片段车辆前轮摆角的参考值。仿真和实验结果表明:通过设置适当的初始参数,该算法能够使自主车辆在行驶过程中完全避开障碍物到达目标点,且轨迹光滑,满足车辆的运动学约束条件。该算法计算简洁、实时性强,适用于底层的实时控制,为自主车辆运动规划提供了一种简便、有效的策略。 相似文献
209.
Kavita Ghosh L.V. Gaikwad R.K. Kalal P.A. Kulkarni Arvind Kumar Shaibal Banerjee Manoj Gupta 《防务技术》2021,17(2):559-570
In the present study,organically modified Montmorillonite clay with polar moiety,the Cloisite 30B,is used for preparation of Hydroxyl terminated polybutadiene(HTPB)-clay nanocomposites(HCN)by dispersion of nanoclay in polymer matrix under high shear mixing.The nanocomposites thus prepared are evaluated in composite propellants as inhibitor material for their functional utility.Several inhibition formulations containing 5 wt%-15 wt%of nanoclay,with or without the conventional filler Sb2O3,were prepared.All these formulations were evaluated for their physical,mechanical,thermal,and ablative properties.Ablation rate and density of the compositions containing Cloisite 30B is around 23%and 5%lower respectively in comparison of the base composition.Strain capability of these compositions is twofold higher than that of base composition.These compositions have also been evaluated for their smoke generation tendency by measuring infra red(IR)attenuation in the wavelength range 1.3 μm-5.6 μm and 8 μm-13 μm and thereby compared with the base composition.The corresponding results confirmed that the compositions containing Cloisite 30B as filler have much lower IR attenuation than compositions with conventional filler,Sb2O3.Replacement of 5%Sb2O3 by nanoclay showed 8%reduction in IR attenuation rate which further reduced to 16%on replacement of 15%of Sb2O3.Interfacial bonding of HCN based inhibitors is also comparable or even better than conventional inhibitors.Precisely,the nanoclay composites with Cloisite 30B as filler exhibit all desirable properties of an inhibitor. 相似文献
210.
Chemical warfare agents (CWA) are stockpiled in large quantities across the globe. Agents stored in inaccessible facilities need to be destroyed rapidly without dispersing the compounds to surrounding areas. Metal-based energetic formulations are used in such prompt defeat applications to rapidly decompose the CWA by generating a high temperature environment. An alternate, and possibly a more effective decomposition pathway could be provided by chemicidal action of aerosolized condensed combustion products, which typically consist of metal oxides. Toxic fumes that escape the high tem-perature blast zone can be neutralized by smoke generated during combustion, depending on the par-ticle size, surface characteristics, chemical properties, and concentration of this smoke. This review considers relevant experimental and modeling studies quantifying decomposition of CWA comprising organophosphorus compounds and their surrogates on the surface of various metal oxides. Dimethyl methylphosphonate (DMMP), a sarine surrogate, was used most commonly for such experiments. Many reported efforts focused on the mechanisms of adsorption of DMMP to various metal oxides and initial reaction steps cleaving various bonds from the chemisorbed molecules. For selected oxides, these ex-periments were supported by quantum-mechanical calculations. In other studies, the capacity of oxide surfaces to adsorb and decompose DMMP was quantified. In most cases, porous catalysts were used although limited experimental data are available for aerosolized nonporous oxide particles. The reported experimental data applicable to scenarios involving prompt decomposition of CWA are summarized. It is noted that information is lacking describing respective heterogeneous reaction kinetics. Preliminary estimates of aerosolized smoke particle concentrations required to destroy CWA are made considering gas phase diffusion rates and reported values of the oxide capacity to decompose CWA or their surrogates. 相似文献