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221.
N+1式高频电力开关电源设计   总被引:3,自引:0,他引:3  
探讨了N+1式高频电力开关电源的组成和工作原理。开关电源由监控模块和整流模块组成,重点研究了均流技术和开关电源的抗干扰措施,论述了整流模块数量N+1的选择。实际运行证明,N+1式高频电力开关电源工作可靠,达到了预期效果。  相似文献   
222.
研究了基于解析冗余的容错控制--控制率重构方法,分析了控制系统中传感器出现故障时其输出信息重构的问题,并针对核反应堆控制系统进行了仿真试验.由试验结果看出,传感器输出信息重构方法是正确的.  相似文献   
223.
介绍了目前国外在核现场处理方面的技术途径以及采用的放射性去污和治理方法,分析了这些方法的优点和效果,并提出了适合中国国情的治理技术。  相似文献   
224.
结合核电站火灾危险的特殊性,阐述了核电站常规岛中网控楼、蓄电池室、汽轮机厂房、电缆隧道、输变电变压器等建筑的火灾自动报警系统设备的特殊配置及选用特点,以发挥火灾自动报警系统的监控作用。  相似文献   
225.
In February 2012, Iran announced its willingness to resume negotiations with the Western powers. This statement followed in the wake of a damning report by the International Atomic Energy Agency (IAEA) Board of Governors and the imposition of additional sanctions by the international community on an Iranian economy already under pressure. Tehran's announcement also coincided with increased speculation regarding an Israeli military strike on Iranian nuclear facilities. At the same time, however, this seemingly positive step appeared to be undermined by Iran's concomitant announcement that “huge” technical progress has been made on Iran's nuclear programme. This article will explore the significance of the recent political, diplomatic and technical developments in the Iranian nuclear affair and situate them in the broader context of Tehran's nuclear strategy. The analysis will assess the potential for this latest phase in the Iranian nuclear crisis to reverse Iran's current trajectory and initiate a rapprochement between Iran and Western powers.  相似文献   
226.
Ian Bellany, an Emeritus Professor of Politics at Lancaster University, died in July 2011 at the age of 70, after a long and painful struggle with myelofibrosis, a rare and invariably terminal blood cancer. Between early 2009 and August 2010, under contract to Hurst & Co., he worked intermittently on a book about nuclear terrorism, which he provisionally entitled Before the Storm. The editor and I are grateful to Michael Dwyer at Hurst & Co. for releasing the draft. What is published here is an edited version of that draft. It may seem presumptuous to speak for Ian, but I am sure he would also have liked to thank the doctors and nurses of the NHS Morecambe Bay Universities Hospital Trust, whose skill, knowledge, and flair for improvisation kept him alive and writing for much longer than anyone expected. Alastair Bellany, Rutgers University, New Jersey, USA.
In the past, terrorists have tended to eschew acts of extreme violence for fear of alienating those whom they wish to persuade and attract to their cause. The first to discard this philosophy was the Aum group in Japan, which sought to use anthrax and acquire a nuclear weapon. Since then, attitudes have changed, spurred on by the impact on public perception of the successful Al Qaeda 9/11 attack on New York and Washington. By crossing the line between moderation and extreme violence, terrorist groups retain one valuable capability: they are much less easily deterred and have few inhibitions. This article considers the three nuclear options open to terrorists – produce a radiological contaminant bomb; build a nuclear bomb; or steal or get given a nuclear device. It examines the possibilities and probabilities of each option and considers how the implementation of the Nuclear Non-proliferation Treaty (NPT) provisions might impose some constraints on terrorists’ nuclear ambitions. By examining the doubtful nuclear security practices of different states and providing statistical evidence of an increase in levels of international terrorist violence, this article points to determined terrorists in time acquiring the means to acquire one or other variants of a nuclear weapon. It concludes that it is not a matter of “if” but “when.”  相似文献   
227.
The idea of ‘clean’ bombs, nuclear weapons with a reduced amount of radioactive fallout resulting from their fission part, has met much ridicule since its public inauguration in 1956. Many scholars have regarded the bombs as a propaganda tool, stopping short of analyzing their role in the transformative phase of US nuclear strategy in the 1950s. This paper reexamines the clean bomb episode through 1958, shedding light upon the dynamic relationship between the development of nuclear weapons technology and the evolution of nuclear strategy from massive retaliation to flexible response. It also discusses the mechanism and momentum of nuclear weapons technology innovation until the US suspended nuclear testing in late 1958.  相似文献   
228.
229.
This note implements the sensitivity analysis suggested by Sandler and re‐examines the robustness of the concordance between NATO benefits and burdens.  相似文献   
230.
This note refutes criticism raised by Solomon about past tests used to ascertain the concordance between NATO benefits and burdens. In so doing, a case is made for keeping the benefit proxy based on exposed borders. Moreover, a truer sensitivity analysis than that offered by Solomon is suggested.  相似文献   
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