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881.
Nancy W. Gallagher 《The Nonproliferation Review》2013,20(3-4):469-498
ABSTRACTSince the end of the Cold War, arms control proponents tried to make the case for deep nuclear reductions and other forms of security cooperation as necessary for strategic stability. While different versions of strategic stability analysis did sometimes produce innovative proposals, constructive negotiations, and successful ratification campaigns in the past, this analytical framework has become more of a hindrance than a help. Treating arms control as a predominantly technical way to make deterrence more stable by changing force structure characteristics, military operations, relative numbers of weapons on either side, or total number of nuclear weapons gives short shrift to political factors, including the fundamental assumptions about world politics that inform different arms control logics, the quality of political relations among leading states, and the political processes that affect negotiation, ratification, and implementation. This article compares two logics for arms control as a means to enhance strategic stability, one developed by the Cambridge community in the 1960s and one used by the Reagan administration and its successors, with current perspectives on strategic stability in which flexibility and freedom of action are preferable to predictability and arms control. It also contrasts what the Barack Obama administration has tried to achieve through strategic stability dialogues with Russia and China with how they envision security cooperation. It then presents an approach developed during the Cold War by Hedley Bull for thinking about both the technical and the political dimensions of arms control, and suggests that the logic of Cooperative Security (which shares important features with Bull's approach) is a more appropriate and productive way to think about arms control in the twenty-first century than strategic stability analysis is. 相似文献
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Russian naval nuclear fuel and reactors pose both proliferation and environmental threats, ranging from the possible theft of highly enriched uranium fuel to the radioactive contamination of the environment, whether due to accident, neglect, or sabotage. Current conditions at Russian naval bases, together with a history of accidents and incidents involving Russia's nuclear fleet, make a convincing case for the large-scale assistance that the G8 is now providing to improve the safety and security of Russian naval reactors and fuel. However, virtually no data has been released to allow accurate, reliable, and independent analysis of reactor and fuel properties, risking misguided international efforts to assist in the areas of nuclear cleanup, nonproliferation, and security. This article identifies and assesses relevant properties and developments related to reactor and fuel design, provides a comprehensive presentation of Russian nuclear naval technologies, and examines technological trends in the context of proliferation and environmental security. 相似文献
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从单无人机机动飞行向多机协同扩展的通用规划框架出发,介绍了其中各模块相关研究的基本原理、代表性方法和前沿研究,主要包括用于环境障碍感知的实时导航地图构建、离散空间的路径规划、连续空间的轨迹规划、基于离散连续混合空间的规划、多航迹或轨迹的协同规划。综合无人机通用规划框架的关键技术,提出了无人机协同机动规划下一步需要重点研究的方向。 相似文献
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近年来,超大体量建设工程大多通过性能化防火设计方法解决超规范设计的问题,虽然性能化防火设计在理论、模拟计算和分析论证上满足设定安全目标,但设计评估过程忽视我国国情、社会环境影响、公民素质及安全管理水平等实际情况,过分依赖后期管理,如处理不当,极易产生新的消防安全隐患.以某商业综合体为例,分析性能化防火设计的建筑物在实际消防监督工作中的局限性,旨在提醒各级消防监管部门、性能化设计评估单位、评审专家充分认识外部环境对性能化设计方案的影响,使性能化设计更加符合实际. 相似文献
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针对线性方程组传统教学中的一些问题,给出了引入线性方程组、解线性方程组、分析解结构的渐进性三步教学设计,同时给出了maple求解线性方程组的两种方法,将理论与实践初步结合了起来,丰富了教学手段,激发了学生的学习兴趣。 相似文献
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