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161.
为研究悬臂式围护桩结构的内力、弯矩、位移和嵌固段的变化规律及特点,结合西宁火车站综合改造工程,对该深基坑支护结构在不同开挖工况条件下悬臂桩的受力性状与内力传递特征进行现场动态测试试验。试验结果表明:悬臂桩的受力特征与理论值有所差异,在实际设计中可对其在配筋方式、混凝土强度设计、嵌固段长度等方面进行优化。试验结果可以有效优化桩身设计,为复杂基坑在开挖过程中的支护结构受力及变形提供参考性依据。  相似文献   
162.
增强信誉机制对信誉信息的有效聚合能力是信誉系统成功的基础。已有的基于局部信誉信息的信誉系统难以有效处理节点的复杂策略不诚实推荐行为,并且可能把提供诚实推荐的节点错误划分为不诚实节点。对此,提出了一种可信度增强的信誉机制CERep。该机制中,节点基于自身的经验产生的直接信任评价,包含直接信任评价值和关于此评价值的信心因子两个部分。在此基础上,提出了新的基于信誉的信任评价算法和推荐可信度计算模型,并给出了信誉机制的分布式实现策略。分析和模拟实验表明,CERep信誉机制能够有效应对复杂策略的不诚实推荐行为,提高信任评价的准确性,实现对节点推荐可信度更公平的评价。  相似文献   
163.
The authors propose five principles for addressing the major deficiencies of the current treaty-based approach to nonproliferation. These involve: effectively closing the door to withdrawals from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT); defining which nuclear technologies fall within the NPT's “inalienable right” provision, so as to maintain a reasonable safety margin against possible military application; expansion of International Atomic Energy Agency inspections to include greater readiness to use its “special” inspection authority; creation of an NPT enforcement regime, to include a secretariat; and universalizing the NPT so as to apply to all states, while creating a path for current non-parties to come into compliance. There is no illusion here about the prospects for the adoption of this approach. At a minimum, the world needs to be frank about the gap between nuclear programs and current nonproliferation protection. Encouragement of greater use of nuclear power should be predicated on closing that gap.  相似文献   
164.
为研究复杂电磁环境对某引信的影响,从双源连续波入手,运用双源连续波对工作状态某引信辐照的实验方法进行实验.实验结果表明,在以引信工作频率为中心的150MHz频率范围内对加电引信进行双源连续波辐照实验可使引信发火,辐照结束后引信工作正常,实验的重复性较好.两连续波频率间隔不同,可使引信发火的场强组合数值大小不相同,实验中当两连续波远离引信工作频率且频差10MHz以上时,发火场强组合近似呈线性.最后对双源连续波对引信的辐照效应机理作了分析,两连续波频率间隔不同,引信发火机理不同.  相似文献   
165.
Landau用序参量的幂级数展开来表示相变温度附近的自由能,强调对称性与序参量在相变中的作用.正确书写自由能形式,可以计算可能相的温度曲线,得到关于序参量的方程,从而推知系统的结构.  相似文献   
166.
African states are hampered by unreliable electric energy that has not complemented economic development efforts. Recently, several African states announced plans to pursue nuclear energy in the future. However, several challenges remain for these states, notably insecurity and financial deficiencies. This paper proposes the use of regional integration arrangements to address these challenges faced by African states, as a way of complementing other efforts enabling African states to obtain nuclear energy. The existence of these arrangements and their institutional mechanisms can enable African states to enhance security and cost-effectively develop nuclear power infrastructure.  相似文献   
167.
ATOMS FOR PEACE     
Atomic Assistance: How “Atoms for Peace” Programs Cause Nuclear Insecurity, by Matthew Fuhrmann, Cornell University Press, 2012, 344 pages, $29.95.  相似文献   
168.
With the exception of Iran, no Middle Eastern state has an operating nuclear power reactor. Several states, including the United Arab Emirates, Saudi Arabia, Qatar, Kuwait, Israel, Syria, Jordan, Turkey, and Egypt are considering constructing such reactors; some have even taken steps towards commencing nuclear power projects. There exist, however, considerable economic, technical, safety, and security challenges to achieving these goals, many of which are acute in the Middle East region. Regional and international cooperation on nuclear technology could not only help regional states meet their energy objectives, but it could also help to build trust among states as a basic step towards a future Middle East Weapons of Mass Destruction-Free Zone.  相似文献   
169.
Indonesia, Thailand, and Vietnam recently announced that they are launching nuclear energy programs, and Malaysia and the Philippines soon may follow suit. As a result, by 2020, at least three states in Southeast Asia could possess latent nuclear capabilities—the option to pursue military applications of dual-use nuclear technology. Analysis of the nuclear programs, domestic proliferation pressures, and the external threat environment in Southeast Asia leads the authors to conclude that the nuclear intentions of states in that region are entirely peaceful and the probability of future nuclear breakout there is low. However, this finding does not justify complacency. In the long term, the benign outlook for regional security may change, and in the near term weak regulatory regimes present serious challenges to nuclear safety and create opportunities that non-state actors may exploit. To minimize these risks, the authors recommend creating a “proliferation firewall” around the region, which would combine strong global support for Southeast Asian nuclear energy programs with innovative regional multilateral nuclear arrangements.  相似文献   
170.
枪械机构故障可靠性分析方法研究   总被引:2,自引:0,他引:2  
介绍枪械机构组成、机构动作和作用,利用可靠性故障分析法中常用的FMECA分析法和FTA分析法对枪械机构产生的故障进行定性分析,并通过某典型自动步枪可靠性试验数据进行统计分析,找出枪械机构动作的主要故障,设计出FMECA分析表和FTA故障树.通过以上分析,提出一些对枪械机构的设计要求.  相似文献   
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