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231.
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
232.
辛越 《中国人民武装警察部队学院学报》2014,(7):31-34
2012年9月颁布的《联合国维和警察防暴队行动能力评估标准作业程序》对联合国防暴队甄选及行动能力评估的组织、实施程序、考查标准等方面都进行了较大的调整。从联合国维和警察防暴队甄选标准作业程序的改革入手,以考试为突破口和着眼点,研究程序的改革对维和警察防暴队培训的影响,制定应对策略,以时维和培训工作具有指导作用和借鉴意义。 相似文献
233.
利用变形协调方程,推导了复合材料帽形加筋梁的等效弯曲刚度公式,建立了复合材料帽形加筋梁的应力、挠度计算公式.计算了均布荷载作用下,不同边界条件下复合材料帽形加筋梁的应力和挠度,并进行了帽形加筋梁的三点弯曲强度试验.对比分析了数值计算结果和试验结果,结果表明:理论计算结果和试验结果吻合较好,说明该方法以及推导的计算公式是可靠的,易于在复合材料船体初步设计阶段中使用. 相似文献
234.
测试序列优化设计是故障诊断中的重要组成部分,最优测试序列能提高故障诊断的效率,常见的故障诊断系统均基于二值属性,而多值属性系统的测试优化问题研究的较少。针对多值属性系统测试序列优化问题的特点,提出了一种改进蚁群算法,结合二值属性系统和多值属性系统的关系,设计了适应于多值属性优化的状态转移规则和信息素更新机制。针对在等测试费用和故障先验概率的情况下不能寻优的问题,制定了对应的优化标准,符合实际的测试需求。通过对比试验,证明了其能解决电子系统多值属性系统的序列优化问题,扩展了多值属性电子系统的测试优化策略。 相似文献
235.
This study revisits the causal linkages between military spending and economic growth in China and G7 countries (i.e. Canada, France, Germany, Italy, Japan, the UK, and the USA) by focusing country-specific analysis for the period 1988–2010. The panel causality analysis, which accounts for both cross-country dependency and heterogeneity across countries, is employed in this study. Our results find evidence of the neutrality hypothesis for Italy, France, and Germany, the military spending–growth detriment hypothesis for both Canada and the UK, and one-way Granger causality running from economic growth to military spending for China. Furthermore, we find a feedback between military spending and economic growth in both Japan and the USA. Thus, our results do not support that one size fits all. 相似文献
236.
Mwita Chacha 《African Security Review》2013,22(4):38-50
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
237.
Lyndon Burford 《The Nonproliferation Review》2013,20(2):229-239
The funding of international nuclear risk mitigation is ad hoc, voluntary, and unpredictable, offering no transparent explanation of who is financially responsible for the task or why. Among many non-nuclear-armed states, this exacerbates a sense of injustice surrounding what they see as a discriminatory nuclear regime. The resulting erosion of the regime's legitimacy undermines support for efforts to prevent nuclear weapons dissemination and terrorism. This article proposes a transparent, equitable “nuclear-user-pays” system as a logical means of reversing this trend. This system envisions states contributing financially to international efforts to mitigate nuclear risks at a level relative to the degree of nuclear risks created by each state. “National nuclear risk factors” would be calculated by tabulating the risks associated with each state's civilian and military nuclear activities, as well as advanced dual-use and nuclear-capable missile activities, multiplying the severity of each risk by the probability of it occurring, and combining these results. A nuclear-user-pays model would create financial incentives for national and corporate nuclear risk mitigation, boost legitimacy and support for nuclear control efforts among non-nuclear-armed states, assist in preventing nuclear weapons dissemination and terrorism, and advance nuclear disarmament by helping progressively devalue nuclear weapons. 相似文献
238.
Sumit Ganguly 《The Nonproliferation Review》2013,20(3):577-581
South Asian Security and International Nuclear Order: Creating a Robust Indo-Pakistani Nuclear Arms Control Regime, by Mario Esteban Carranza. Ashgate, 2009. 208 pages, $99.95. 相似文献
239.
Henry Sokolski 《The Nonproliferation Review》2013,20(1):179-184
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
240.
Ephraim Asculai 《The Nonproliferation Review》2013,20(3):391-400
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