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841.
Abstract

This article analyses changes and failures in the northern Mali system of security governance, taking into account the period running from the declaration of the Malian Third Republic (1992) to the present. Considering northern Mali as an area of limited statehood, the article develops a comparative diachronic analysis, distinguishing between three phases, namely Militiarisation (1992–2002), Fragmentation (2002–2012) and Multiplication (2013–ongoing). For every phase the focus is on (1) the mechanisms of coordination among actors, (2) the distribution of coercive capacities and ruling power and (3) the forms of authority. Unintended consequences and collective problems are highlighted, in order to understand the current situation of insecurity in the area.  相似文献   
842.
ABSTRACT

While some Foucault-inspired studies construe local ownership in international interventions as a form of liberal governmentality that aims to govern through freedom, others lambast it as an illiberal governmentality that is likely to be resisted because it undermines local autonomy. However, we still do not know what is the rationality behind local ownership, how it is being operationalized, and why a principle that aims to govern through freedom ends up curtailing it. I argue that local ownership, echoing the colonial principle of indirect rule, is driven by the rationality of advanced democracies on how best to govern global insecurities at a distance. Consequently, ownership is operationalized as responsibilization for externally designed objectives. This often gives rise to local resistance which undermines international efforts to achieve ownership. I illustrate my arguments with evidence from the EU Mission on Regional Maritime Capacity Building in the Horn of Africa (EUCAP Nestor).  相似文献   
843.
ABSTRACT

The slow moving conflict in the South China Sea has been characterized by some as “not worth the candle.” China claims the entirety of the South China Sea pursuant to a nine-dash line, the legal impact of which has been limited by international courts. At the same time, China has changed the reality of control over the South China Sea by building a number of fortified islands in the Spratly Islands and elsewhere. The US has either refused to stand up to China's behavior (Obama) or responded unevenly (Trump). This paper examines the impact of China's behaviour on local parties, US interests, and the liberal international system.  相似文献   
844.
《防务技术》2020,16(1):96-106
The numerical simulation of a blast wave of a multilayer composite charge is investigated. A calculation model of the near-field explosion and far-field propagation of the shock wave of a composite charge is established using the AUTODYN finite element program. Results of the near-field and far-field calculations of the shock wave respectively converge at cell sizes of 0.25–0.5 cm and 1–3 cm. The Euler––flux-corrected transport solver is found to be suitable for the far-field calculation after mapping. A numerical simulation is conducted to study the formation, propagation, and interaction of the shock wave of the composite charge for different initiation modes. It is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the composite charge. Additionally, it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation, and the peak pressure of the shock wave exponentially decays, fitting the calculation formula of the peak overpressure attenuation under different initiation modes, which is obtained and verified by experiment. The difference between numerical and experimental results is less than 10%, and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation.  相似文献   
845.
《防务技术》2020,16(5):969-979
Shock wave is emitted into the plate and sphere when a sphere hypervelocity impacts onto a thin plate. The fragmentation and phase change of the material caused by the propagation and unloading of shock wave could result in the formation of debris cloud eventually. Propagation models are deduced based on one-dimensional shock wave theory and the geometry of sphere, which uses elliptic equations (corresponding to ellipsoid equations in physical space) to describe the propagation of shock wave and the rarefaction wave. The “Effective thickness” is defined as the critical plate thickness that ensures the rarefaction wave overtake the shock wave at the back of the sphere. The “Effective thickness” is directly related to the form of the debris cloud. The relation of the “Effective thickness” and the “Optimum thickness” is also discussed. The impacts of Al spheres onto Al plates are simulated within SPH to verify the propagation models and associated theories. The results show that the wave fronts predicted by the propagation models are closer to the simulation result at higher impact velocity. The curvatures of the wave fronts decrease with the increase of impact velocities. The predicted “Effective thickness” is consistent with the simulation results. The analysis about the shock wave propagation and unloading in this paper can provide a new sight and inspiration for the quantitative study of hypervelocity impact and space debris protection.  相似文献   
846.
Military units can become to some extent self-governing in war-time battle. At times, they may take the discipline of their soldiers into their own hands and such discipline may be severe. This paper examines incidents in the British military, in both World Wars, where British soldiers were killed by their comrades because they would not fight in the heat of battle. The judicial execution by the military authorities of deserters in the First World War led to much controversy in Britain. It may be much less well-known that in both World Wars there was, on occasion, an extra-judicial practice within the British military of executing soldiers who would not fight in the heat of battle. In such situations ethical dilemmas become very difficult indeed and some of the relevant issues are examined here.  相似文献   
847.
武器装备维修是武器装备维修保障的重要内容,加强装备维修绩效评价,建立科学规范的绩效评价指标体系,对深入推进装备维修工作健康发展将发挥积极作用。以平衡计分卡为研究手段,运用"5M1E"分析法,从一个内核和四个维度出发,分析武器装备维修绩效评价的影响因素,据此建立评价指标体系,并应用于装备维修管理实践,为有效提高装备维修保障效益提供有益借鉴。  相似文献   
848.
中国现代文学史的教学应该有文献史料运用的意识,在文学作品解读的基础上充分利用教材中所列的文献史料,并认真查阅,从文学史现象的历史和文学史叙述本身的过程中掌握现代文学史的知识脉络。同时也需结合时代发展下教材的编写特点和学生学习的新习惯,在互联网教学平台上使用编写者提供的文献史料资源,多方面、多层次地进入到现代文学史的教学中。  相似文献   
849.
以舰船棱柱形的全封闭桅杆为研究对象,利用计算流体力学软件ANSYS ICEMCFD和ANSYSCFX对模型进行数值实验。在雷诺数为5.74×105和7.66×105,桅杆的攻角从0°变化到90°,以15°为间隔的条件下,研究了表面倾斜且前后不对称的四边形棱柱状结构在均匀流场中所受的流体载荷。通过对桅杆绕流进行数值模拟,得到了漩涡发放随时间的变化规律;发现模型由于表面倾斜的原因,除了受到阻力和升力外,还受到垂直方向上的垂向力,这在以往的柱状结构中是没有的;同时分析了模型所受的定常力和脉动力系数随雷诺数和攻角的变化规律。  相似文献   
850.
研究地网对垂直偶极子天线辐射特性的影响。建立了该天线的仿真模型,采用基于矩量法的仿真软件计算了铺设地网后垂直偶极子天线增益、输入阻抗、最大辐射仰角、3 dB波瓣宽度等辐射特性。结果表明,地网中心偏离天线振子正下方0.75λ时能显著提高天线的增益,改变地网大小和铺设密度也能在一定程度上提高天线的增益。  相似文献   
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