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801.
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   
802.
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   
803.
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   
804.
《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   
805.
《防务技术》2020,16(4):893-899
Based on the elastic theory of cylindrical shells and the theory of composite laminates, a prediction model for the residual prestress of the simplified round composite barrel for railgun is established. Only the fibre pretension is considered in this model. A three dimensional numerical simulation for the residual prestress in the railgun barrel is carried out, by combining the temperature differential method with the element birth and death technology. The results obtained by the two methods are compared. It reveals that the distribution trends of residual prestress are consistent. And the difference for residual prestress in the filament wound composite housing of barrel is relatively small. The same finite element method is used to analysis the residual prestress in the non-simplified composite barrels for railgun, which are under different control modes of winding tension. The results mean that the residual prestress in barrel will increase while the taper coefficient for winding is decreasing. Therefore, the sealing performance in bore is improved, but the strength of the filament wound composite housing drops. In addition, the axial and circumferential residual prestress in the filament wound composite housing with constant torque winding are close to the ones in iso-stress design for barrel.  相似文献   
806.
《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   
807.
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   
808.
受国际毒潮的影响,我国的毒品犯罪形势日趋严峻和复杂,而在毒品犯罪中,走私、运输毒品犯罪占有相当大的比例。由于毒品的走私和运输,带来了毒品的消费,引发了吸毒的蔓延,我国的毒品问题呈现出“多头入境、多线渗透、多点中转、多地集散、多地消费”的状况。研究走私、运输毒品案件的特点,有助于了解走私、运输毒品案件的规律,指导禁毒部门采取有针对性的侦查对策,有力地打击走私、运输毒品犯罪。  相似文献   
809.
从日本建立创新型国家具有的优势进行研究,并从多方位多角度去发现其具有的特点及意义来论证日本建立创新型国家对我国建立创新型和谐社会所具有的参考价值,从中考虑如何对未来我国发展模式的框架进行构建。  相似文献   
810.
商业建筑火灾荷载调查和统计分析   总被引:1,自引:0,他引:1  
火灾荷载是判断建筑室内火灾危险程度的依据,也是性能化防火设计中设计火灾的重要内容。调查了在廊坊、长治、郑州及天津四个城市的零售类商业店铺火灾荷载情况,调查的对象包括快餐店、服装店、鞋店等商业零售店铺。针对这些店铺常见的可燃物形式,确定了5种可燃物,分析它们在总火灾荷栽中的比重。共计调查了117家商业店铺,总面积4095m^2,面积最小为2.5m^2,最大为185m^2。这117家店铺的火灾荷载密度与样本数之间具有对数正态分布,调查得到的所有店铺火灾荷载密度平均值为1230MJ/m^2,最大值6813.4MJ/m^2,最小值92MJ/m^2,标准偏差1240.5MJ/m^2。  相似文献   
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