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排序方式: 共有547条查询结果,搜索用时 828 毫秒
61.
基于MSP430单片机的海浪水压场自动测量系统 总被引:1,自引:1,他引:0
提出了基于MSP430单片机的水压场自动测量系统的设计方案和实现方法并进行了实际测量.解决了自动测量系统中的低噪声、低功耗、高分辨率、大容量存储等关键技术.实验结果表明:该系统具有自动运行、电池供电、记录时间长等特点.适于高海况条件下的海浪水压场的测量. 相似文献
62.
用有限时间热力学的方法分析具有热阻、热漏、内不可逆性的定常流联合卡诺型热机循环.导出了在傅立叶导热定律下联合循环功率、效率和生态学指标的性能,并进行优化;得到功率、效率和生态学指标之间的优化关系,并由数值计算分析了功率、效率和循环熵产率之间的关系.所得的结果表明,最大生态学指标下的效率十分接近于联合循环可以达到的最大效率;相应的熵产率也要低于以输出功率为优化目标时的熵产率. 相似文献
63.
模糊逻辑系统在船舶风险评估中的应用 总被引:4,自引:2,他引:2
为了合理进行船舶风险评估,提出了一种基于模糊逻辑系统的船舶风险评估方法.根据模糊逻辑系统的基本原理,建立了船舶风险评估的模糊逻辑模型;按照国家标准、规范,并结合经验建立了风险指标的模糊集合、风险矩阵及模糊规则,然后进行了模糊推理,得到了系统的风险等级,并制定了预防风险的措施.以某艇消防系统的风险评估为例,证明了其能够合理地评估出系统的风险,可为决策提供参考. 相似文献
64.
Gerald Felix Warburg 《The Nonproliferation Review》2013,20(3):451-471
On October 1, 2008, Congress enacted a proposal that originated with President George W. Bush in 2005 to approve an unprecedented nuclear trade pact with India by removing a central pillar of US nonproliferation policy. Despite the numerous political challenges confronting the Bush administration, the initiative won strong bipartisan support, including votes from Democratic Senators Joseph Biden, Hillary Clinton, and Barack Obama. The four-year struggle to pass the controversial US-India nuclear trade agreement offers an exceptionally valuable case study. It demonstrates a classic tradeoff between the pursuit of broad multilateral goals such as nuclear nonproliferation and advancement of a specific bilateral relationship. It reveals enduring fault lines in executive branch relations with Congress. It vividly portrays challenges confronting proponents of a strong nonproliferation regime. This article is based on an analysis of the negotiating record and congressional deliberations, including interviews with key participants. It assesses the lessons learned and focuses on three principal questions: how did the agreement seek to advance US national security interests?; what were the essential elements of the prolonged state-of-the-art lobbying campaign to win approval from skeptics in Congress?; and what are the agreement's actual benefits—and costs—to future US nonproliferation efforts? 相似文献
65.
Digby Waller 《Defence and Peace Economics》2013,24(2):225-241
Data limitations arising from non‐transparency in military expenditure reporting impose significant constraints on economists studying country and comparative developments in this field. This article focuses on the case of China. It reviews the recent literature on China's military expenditure, examines the variance in published estimates, and identifies three factors which help explain the variance: budgetary falsification; non‐budgeted PLA revenue; and the US dollar purchasing‐power parity of the yuan. Conclusions emphasize important policy implications of such variance and suggest a more active role for defence economists in a field of research generating considerable attention from international relations scholars. 相似文献
66.
Leonard Weiss 《The Nonproliferation Review》2013,20(2):269-284
The phenomenon of global warming has led to a revival of the prospects for increased nuclear energy production worldwide, yet such increased production carries with it the increased risk of proliferation. To mitigate this risk, various multinational arrangements have been proposed to provide reliable supply of nuclear fuel while at the same time discouraging the construction of national plants for nuclear enrichment and reprocessing. This article provides a brief history of some of these proposals and concludes that the likelihood of success for such schemes as effective tools for nonproliferation is not high at this time. A proposal from the World Council on Renewable Energy to expand the understanding of supplier obligations under Article IV of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) to include the development of non-nuclear energy technologies for NPT parties in good standing is potentially a much better nonproliferation tool. Such an approach tracks the ideas contained in Title V of the Nuclear Non-Proliferation Act of 1978, which has recently received revived congressional interest. 相似文献
67.
基于LDO稳压器在电磁干扰(EMI)下产生直流偏移失效的机理分析,展开敏感度建模与仿真方法研究。使用一款实验芯片,创新地引入片上电压传感器,用于测试EMI在LDO稳压器内部的传播特性。在敏感度建模中,建立等效电路模型,通过直流功能测试,Z参数阻抗特性测试验证模型的正确性,将该模型用于LDO稳压器的敏感度预测。在敏感度仿真过程中,通过分析关键子电路和不断增加寄生元件,仿真不同寄生因素对敏感度影响的权重。将仿真结果与传导直接注入法(DPI)片上测试结果对比,仿真结果与DPI测试在频域1MHz至1GHz匹配。 相似文献
68.
民族地区社会转型推动高校思想政治理论新课程的实施。新课程需要遵循新的教学理念:以学生为主体,教师为主导;以师生互动,关注教学过程为关键;面向生活实际,灵活运用多种教学手段和方法,创新考核方式,加大课外实践力度。创新教学模式,增强教育实效性是一项任重道远的研究课题。 相似文献
69.
70.
考虑到舰船环境限制和高能脉冲负载对储能的需求,有必要对储能装置进行合理的选型和优化配置,来提升综合电力系统性能。为此,基于带权极小模理想点法和层次分析法,提出了一种储能装置性能评价函数,并以其为优化目标,进行储能装置优化配置。所提出的评价函数充分考虑系统需求和脉冲负载特性,以储能装置体积、质量和经济性作为评价函数主要组成部分,同时考虑功率、能量、电压、荷电状态等约束,建立优化配置模型,并采用差分进化算法进行求解。以高性能锂电池和超级电容器为例,对所提模型进行求解计算,结果表明在所给权重系数下锂电池性能更优,更适用于综合电力系统,并给出了优化配置后的指导方案。 相似文献