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251.
Birte Julia Gippert 《Contemporary Security Policy》2018,39(1):51-71
ABSTRACTThis article explores the interaction between local and international power structures in EU peacebuilding. While citizens in a state only face order from one authority (the state), local actors in a peacebuilding context are subject to orders from two institutions (the domestic state and the peacebuilding mission). This article explores the nature of interactions of these two institutions and their effect on local police officers’ compliance and resistance. Specifically, it analyzes the example of the police restructuring process in Bosnia and Herzegovina. It demonstrates that the choices of local officers to comply or resist depended on whether the interactions between the EU Police Mission and the local police organization were positive and mutually supportive, or whether they were competitive and contradictory. The findings of the article contribute to the debates on the role of local power and the importance of local legitimacy in peacebuilding. 相似文献
252.
Adam D. Bramoweth James Luther Barbara H. Hanusa Jon D. Walker Charles W. Atwood Jr. Anne Germain 《Defence and Peace Economics》2018,29(1):78-90
AbstractInsomnia is prevalent among Veterans with post-traumatic stress disorder (PTSD), it exacerbates PTSD symptoms, and it contributes to impaired functioning and quality of life. To improve treatment outcomes, it is important to identify risk factors for insomnia and sedative-hypnotic use. Classification and regression trees and logistic regression models were used to identify variables associated with insomnia or sedative-hypnotic use. Key findings include low insomnia diagnosis rates (3.5–5.6%) and high rates of sedative-hypnotics (44.2–49.0%). Younger Veterans and those without a breathing-related sleep disorder (BRSD) were more likely to receive an insomnia diagnosis. Veterans with greater service connection and those with an alcohol/substance use disorder were more likely to be prescribed sedative-hypnotics. Interaction terms may have identified potential groups at risk of being under-diagnosed with insomnia (i.e. non-black Veterans with psychiatric co-morbidity, black Veterans without psychiatric co-morbidity) as well as groups at risk for sedative-hypnotic use (i.e. younger Veterans without BRSD). In sum, Veterans with PTSD have high rates of sedative-hypnotic use despite minimal evidence they are effective. This is counter to recommendations indicating behavioral interventions are the first-line treatment. Policy changes are needed to reduce use of sedative-hypnotics and increase access to behavioral insomnia interventions. 相似文献
253.
Carlos Martí Sempere 《Defence and Peace Economics》2018,29(3):225-246
This article surveys the body of available evidence regarding the spill-over effects of defence R&D. It reviews the routes through which defence R&D spills over to the economy with positive externalities – in terms of new products, technologies or processes; the barriers that impede or block such a process; potential negative repercussions, and the measure of such effects. The main conclusion is that the uncertainty of these effects, and the inaccurate appraisal of their value, hardly supports informed decisions concerning defence R&D policies. 相似文献
254.
针对机载航电系统自身辐射源特性,提出一种不依赖敌方探测设备的机载航电系统射频隐身性能评估方法。分析机载航电系统设备在极化域、波形域、能量域中影响射频隐身性能的因素,构建极化域、能量域、波形域射频隐身指标,打破常规的"辐射-接收"模型的隐身性能评估方法,建立基于机载航电系统自身辐射信号工作状态和工作参数的射频隐身定量评估方法。对机载雷达系统进行仿真评估,结果表明,该评估方法能正确反映机载雷达系统的射频隐身性能。 相似文献
255.
Major William Selber 《Small Wars & Insurgencies》2018,29(2):344-366
Since the fall of the Taliban in late 2001, the Islamic Republic of Afghanistan (GIRoA), the United States, the United Nations, and the International Security Assistance Force (ISAF) have funded and led three different Disarmament, Demobilization, and Reintegration (DDR) programs. Despite a significant investment in time and treasure, all of them have failed to significantly reduce the number of insurgents or arbaki (militia). This article explores why these programs failed despite incorporating ideas from the prominent DDR schools of thought. Utilizing Stathis Kalyvas’ theory of The Logic of Violence in Civil War as a lens, this article argues that GIRoA and ISAF did not have sufficient control of territory to entice insurgents or arbaki to reconcile and/or reintegrate with the government. Further, in areas GIRoA nominally controlled in northern and western Afghanistan, regional powerbrokers who controlled these areas balked at these programs. 相似文献
256.
针对具有反作用控制系统(Reaction Control System,RCS)和气动舵两类控制机构的再入飞行器,提出一种基于脉宽脉频(Pulse-Width Pulse-Frequency,PWPF)调节器的最优控制分配方法。将RCS的输入信号转化为连续变化量,RCS与气动舵的控制分配问题被描述为二次规划问题,并采用有效集方法对其求解。采用离散法和PWPF调节器将优化结果转化为RCS的开关机状态。与混合整数规划问题相比,连续二次规划问题更容易求解,计算速度更快。通过对二次规划问题的重构,该算法能有效地应对故障情况。 相似文献
257.
为了实现利用船舶静态电场对船舶进行跟踪的目的,针对传统卡尔曼滤波算法中存在的问题,设计一种新的非线性滤波器。建立船舶的状态空间模型,分析传统卡尔曼滤波算法在船舶跟踪中存在的问题;依据渐进贝叶斯思想,利用连续白噪声与离散白噪声序列噪声协方差之间的关系,设计一种新的渐进更新扩展卡尔曼滤波器。仿真结果表明,该滤波器能有效地抑制由于初始误差较大而造成的滤波性能下降和滤波发散,能够有效地跟踪船舶,具有较高的实用价值。 相似文献
258.
利用COSMIC掩星任务自2010年至2014年的电离层电子密度廓线,使用只考虑廓线自身特性的4种参数进行质量检核,并对廓线质量的时空分布进行分析。发现在廓线质量的空间分布上,廓线不合格率在高纬地区最高,其次是低纬地区,在中纬地区最低,这可能与电子密度分布在磁赤道附近存在赤道异常、两极地区的磁场强度最大有关。廓线质量的季节变化较明显,在南、北半球,冬、春两季的廓线不合格率均显著高于夏、秋两季。另外,廓线质量具有一定昼夜分布特性,不合格率白天明显较夜晚低,且在晨昏分界线上变化较大。合格廓线的电子密度峰值和峰值高度分布在磁赤道附近明显高于其他区域,呈现"双驼峰"现象。 相似文献
259.
260.
航天力量是各主要军事强国重点投入建设的新型作战力量。本文以航天产业军民两用的天然技术属性作为切入点,从各主要军事强国商业、民用航天的规划建设中研判分析航天力量短期、中期、长期的建设节点,对航天力量走向战场需要突破的瓶颈进行思考,就航天力量建设问题提出思考。 相似文献