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301.
Governments are increasingly recognizing the problem posed by internally weak nuclear-capable states. The problem, however, is under-theorized. This article brings together literature on sovereignty and international order, the nonproliferation regime, and weak states, and introduces new concepts to provide a more structured understanding of this problem. Insight comes from focusing attention on the function and governance of two nuclear estates (termed the production and operational estates), and on their resilience to decay and disorder occurring within the state and society. Drawing on empirical observation, the authors suggest a typology of weakness in nuclear states, involving state fragmentation typified by the former Soviet Union, the “hard weak state” typified by North Korea, and the internally conflicted state typified by Pakistan. Although these types give rise to distinctive difficulties, their alleviation depends heavily on the maintenance of internal authority within the state and estates, the presence or absence of cooperative relations, and the international regulatory framework's vitality.  相似文献   
302.
ABSTRACT

There is growing policy consensus in Washington and other Western capitals that economic sanctions are powerful tools to cope with major foreign policy crises. Are sanctions, particularly targeted sanctions, really the potent instruments optimists suggest? Under what circumstances do punitive economic measures induce policy change in sanctioned countries? To probe these queries, in this article I outline the conditions that have been identified as more likely to lead to successful sanctions outcomes in the literature. I also discuss four major shortcomings of existing scholarship. First, the sender-biased interpretation of sanctions effectiveness renders the treatment of the ‘ineffective’ cases with negative outcomes the same as those cases that induce no discernable change in target behavior. Second, the prevalent use of static data from existing sanctions databases reduces the ability of researchers to study various time-specific factors affecting the probability of sanctions success. Third, the dominant state-centric bargaining model in the literature offers limited insight into contemporary coercive measures directed at non-state actors. Fourth, the study of sanctions in isolation of other instruments that frequently accompany them, such as incentives and diplomatic pressure, leads to a partial understanding of the specific role sanctions play in shaping the outcome of key foreign policy initiatives.  相似文献   
303.
SAVING THE NPT     
For more than forty years, the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) has provided major security benefits to the international community; however, the treaty is suffering from internal and external pressures, and benign neglect on the part of its members is undermining its authority. To ensure the treaty's continued viability, it is time for member states to start showing the NPT the respect it deserves and to renew their commitments to its fundamental purposes. Achieving this requires remedial action in at least four areas of vulnerability: reinvigorating nuclear disarmament; strengthening nonproliferation; overcoming the NPT's institutional deficit; and fostering a rapprochement between NPT and non-NPT states that does not abandon the goal of treaty universalization. There is still time before the 2010 NPT Review Conference for concerted action to restore the NPT's vitality and for the United States to resume its leadership role on behalf of the treaty and its membership.  相似文献   
304.
为合理有效地评估雷达在战场上的生存能力,选取截获概率作为定量评估指标,分析了侦察截获的判断条件,根据截获条件对雷达对抗侦察系统进行功能仿真,建立了基于HLA的评估系统.通过仿真得到了对应时间的截获概率,并以此作为评估雷达生存能力的定量指标.仿真结果表明,采用这种方法得到的截获概率合理,对提高雷达生存能力有一定参考意义.  相似文献   
305.
The Congolese security sector reform – disarmament demobilisation and reintegration (SSR-DDR) process has suffered from setbacks in its military sector during the last 10 years, such as insufficient funding, lack of coordination and domestic reluctance to major changes, with as a result, a very fragile and disjointed Army. These problems have deepened as officers have defected from the Army and caused new instability in the East of the Congo. This article aims to analyse the recent mutinies and the reaction by the Congolese government by applying a capabilities-based approach in combination with a typology of spoilers. The objective is to identify and classify the spoilers and answer the questions of why they emerge now and how they are dealt with on a national level. From the analysis, the author suggests that there are several spoilers involved in the current situation – the most powerful being the Congolese and the Rwandan governments, prompting the question of whether an international involvement is necessary to solve the problem.  相似文献   
306.
Why does peacekeeping sometimes fail? How can effective peacekeepers increase the likelihood of success of a mission? The two main flaws in the current evaluations of peace operations are that they mainly rely on already concluded missions and that they make use of indicators that do not reveal micro-level dynamics. This article introduces an analytical framework relating the effectiveness of soldiers to their actual impact in their area of operation in a peace operation. The framework is called “unit peace operation effectiveness” (UPOE). Focusing on soldiers in peace operations, this article shows that: different units behave differently; emphasize different aspects of the mandate; and are effective in different ways. Ultimately, this has an actual impact on the end-state of the mission. It relies on and adapts classic security studies works to theoretically enrich the peacekeeping literature. The model is tested in an illustrative case study based on ethnographic work on French and Italian units in Afghanistan between 2008 and 2010.  相似文献   
307.
通过设置弹丸初速并研究其对单级磁阻型线圈发射器发射性能的影响,模拟分析前一级线圈弹丸出口速度对后一级线圈发射性能影响的规律;利用Ansoft有限元仿真软件进行了动态仿真,得到弹丸初速对单级磁阻型线圈发射器驱动电流、驱动线圈感应电压、电磁力、弹丸出VI速度、弹丸位移及能量转换效率等影响的规律.研究表明:弹丸初速越大,经过单级线圈加速后弹丸出口速度也越大,但弹丸出口速度增量减小;随着弹丸初速增大,能量转换效率呈现先增大后减小的趋势.  相似文献   
308.
舰船武器装备基准在外界环境作用下产生变化,从而影响武器系统的打击精度。应用ANSYS平台建立舰船有限元模型,利用三维波浪载荷的计算方法模拟航行条件下的波浪力,研究了舰船甲板面武器装备基准在两种极限海况下的变化情况,发现针对此类舰船横摇使武器装备基准产生较大的变化,并且靠近尾部和两舷位置处装备的基准变化较为显著。仿真结果表明:当舰船在风浪中航行使用武器系统时,应尽量采取顶浪航行,减少舰船横摇对武器系统基准的影响。  相似文献   
309.
基于效能的舰艇电子对抗训练效果评估方法   总被引:1,自引:0,他引:1  
摘 要:为解决舰艇电子对抗专业训练缺乏统一评估标准与方法体系等实际评估难题;采用系统分析方法结合舰艇电子对抗专业训练实际;研究提出了基于“任务要求分解”的作战效能量化指标体系构建方法、训练效果表达方法及实用评估指标体系、定量指标评估模型、评估标准等舰艇电子对抗训练效果评估方法体系;能够满足专业训练效果评估所需,对其它专业军事训练效果评估工作亦具有借鉴意义。  相似文献   
310.
针对海洋环境对鱼雷等武器装备战术效能影响的试验数据和案例样本匮乏等普遍性问题,引入信息扩和模糊映射思想,并基于遗传算法改进和发展了最优窗宽扩散模型。该方法可从有限的试验样本中客观拟合出数据结构信息,进而实现有限数据样本信息的合理扩散。利用该方法进行了基于小样本案例的潜射鱼雷战术效能的海洋环境影响评估的信息扩散建模和仿真实验和对比分析。结果表明,窗宽优化的信息扩散模型可有效改进常规信息扩散模型的评估效果,对武器装备环境影响评估中普遍存在的小样本或信息不完备困难有一定参考应用意义。  相似文献   
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