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621.
Recently, post-explosion nuclear forensics, or nuclear attribution, has gained a new spotlight within the nuclear weapons scientific and policymaking community. Academics are beginning to ask whether post-explosion forensics might create a replacement for an international nonproliferation regime, or at least offer a fallback option to deter states and individuals from selling nuclear materials. This paper examines current attribution technology from unclassified literature and finds the technology to be well developed but not foolproof, such that nuclear attribution currently provides little deterrent value. If current capabilities were publicized more thoroughly and if the post-explosion process of assessing the evidence were internationalized, states and intermediate actors might be deterred more effectively. Developing a nuclear fingerprint database is also discussed. While useful, its impact on deterrence would be minimal.  相似文献   
622.
Based on the first-person account of coauthor Pierre Billaud, a prominent French participant, this article describes for the first time in such detail the history of the development of the French hydrogen bomb in the 1960s and the organization of military nuclear research in France. The authors illustrate the extent to which French defense and governmental authorities did not support research on thermonuclear weapons until 1966. Billaud, a project insider, relates the historical episodes that led to France's successful 1968 thermonuclear test, including the names of the individuals involved and how a timely tip from a foreign source hastened the success of the first H-bomb test.  相似文献   
623.
MONGOLIA     
Formed according to broad principles laid out by the United Nations, nuclear-weapon-free zones (NWFZs) play an important role in promoting nuclear nonproliferation, paralleling and complementing the Treaty on the Non-Proliferation of Nuclear Weapons. But the traditional regional treaty-based path to establishing NWFZs is not open to all states. Owing to various factors, some countries cannot realistically follow the path of states that have established traditional NWFZs. Mongolia, having declared itself a single-state NWFZ in 1992 and gained UN General Assembly recognition of this status in 1998, may provide an example for other countries to follow. This viewpoint presents Mongolia's case as a state seeking to acquire a nontraditional nuclear-weapon-free status despite unfavorable geopolitical circumstances. The case of Mongolia clearly demonstrates that the creation of a credible, single-state NWFZ status is possible, but demands the support and flexibility of both neighboring states and the nuclear weapon states.  相似文献   
624.
分析武器装备体系保障需求特征,阐述需求建模的目的,建立需求模型,该模型包括任务模型、任务-节点-能力关系模型及能力需求模型.按照分层思想,定量描述能力需求,为构建未来武器装备体系保障作出探索性研究.  相似文献   
625.
针对一般导引律在载机远距引导中存在的问题,结合远距引导的需求,设计了远距引导的三维变结构导引律。该导引律具有较强自适应性,可以使载机以期望的进入角接近目标。仿真结果表明,载机在该导引律作用下,能以较小过载,平滑轨迹快速接近机动目标,并保证载机引导结束时占有有利的空中战术态势。  相似文献   
626.
射频前端强电磁脉冲前门耦合研究   总被引:1,自引:0,他引:1  
针对强电磁脉冲能量经天线进入射频前端的威胁,给出强电磁脉冲环境的评估方法,通过分析天线-射频前端工作原理,提出全频带脉冲耦合能量的理论计算公式.并以中馈天线-短波电台为例,用电磁仿真软件CST实现了天线仿真与前端电路仿真的有机连接,得出前门耦合数据及其影响因素,此仿真方案也为更深入分析耦合效应、验证防护技术提供了良好平台.最后根据仿真为前门防护提出若干意见.  相似文献   
627.
护理人员良好的人际适应教学能力不仅是临床带教的需要,而且是现代护理服务团队发展的必须。团体辅导对提高护理人员人际适应教学能力方面有很好的作用,主要有完善人际理念,增强护理团队凝聚力,预防团队信息流通障碍,提高临床护理教学质量等。  相似文献   
628.
In the aftermath of September 11, 2001 and Hurricane Katrina, the United States government has spent tens of billions of dollars to improve the nation's ability to respond to a natural disaster or terrorist attack, but the emphasis on immediate first response has left many long-term environmental, political, and technological challenges unaddressed. Although a dirty bomb attack is unlikely to yield the same amount of physical devastation and death as caused by Katrina or a nuclear weapon, the social, psychological, and economic impact would be enormous. At present, however, the United States lacks the technology necessary to decontaminate a large, densely populated urban area under time, political, and economic constraints. This article reviews past cleanup experiences and current decontamination capabilities to consider the long-term implications of a dirty bomb, identifies weaknesses in America's existing response capabilities, notes possible areas of political friction, and considers the implications of the failure to adequately prepare. Having the appropriate decontamination techniques established and long-term plans in place before an incident occurs will significantly improve the government's ability to protect public and environmental security, establish a viable decontamination strategy, allow residents to return to their homes, and get the local economy back on its feet.  相似文献   
629.
基于Gauss伪谱法的空空导弹最优中制导律设计   总被引:3,自引:3,他引:0       下载免费PDF全文
研究Gauss伪谱法在空空导弹最优中制导律设计中的应用。建立空空导弹中制导律设计问题最优控制模型,首次提出采用Gauss伪谱法求解最优中制导律设计问题的思路,详细阐述了求解流程,通过仿真算例验证了求解方法的有效性,并同比例导引、打靶法等传统方法进行了对比。仿真结果表明,综合考虑性能指标、计算精度、计算效率等因素,Gauss伪谱法具有明显优势,Gauss伪谱法求解结果和求解效率与配点个数密切相关。研究结果为空空导弹中制导律设计提供理论参考。  相似文献   
630.
目前求解火力优化配置(WTA)问题的智能算法层出不穷,急需统一的算法评价准则来比较各算法的寻优能力,以得到相对更高精度、更高效率的算法.针对上述问题建立了完善的评价准则体系,从算法代码编制质量、算法精准度和算法执行效率3个方面对智能算法的寻优能力深入讨论,并给出了2个标准测试模型及其初始化参数.实例说明本评价准则科学合理,具有很高的实用价值.  相似文献   
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