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71.
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
72.
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
73.
This article outlines the widespread needs of South African military veterans and the possible consequences if the promises made in the recent Military Veterans Act are not met. The first part of the article defines who generally qualifies as a military veteran, how they are typically compensated in various countries with specific reference to neighbouring southern African countries, and what the consequences are when veterans become disenchanted with the state. The second part focuses on South Africa and the recent debates on military veterans and their entitlements. With reference to the findings of a qualitative study conducted among military veterans, parliamentary debates and media reports, an assessment is made of the demands and affordability of promised benefits and the consequences should the state not deliver. The conclusion is reached that heightened expectations are presently frustrated by slow roll-outs, and this is likely to increase the possibility of protest action. This has now the potential to create further tension within the ruling party and civil society, as the pressure on public finances mounts and demands become unsustainable. The effect this may have on political stability will depend on how the government manages this issue. 相似文献
74.
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
75.
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
76.
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
77.
机动飞行条件下,运动误差的幅度较大,频域运动补偿精度难以满足机载超宽带合成孔径雷达(UWB SAR)高精度成像的要求,需要采用精确的时域后向投影(Back Projection,BP)算法,然而原始BP算法的巨大计算量限制了其实际应用。提出了一种基于子图像快速因式分解BP(Sub-image Fast Factorized BackProjection,SIFFBP)算法的机动飞行条件下机载UWB SAR成像方案,并对其子孔径和子图像划分的约束关系进行了推导,给出了算法步骤,并分析了算法的计算量。仿真和实测数据处理结果表明,SIFFBP算法能够在保证处理精度的同时,大幅度提高处理效率,非常适合于机动飞行条件下的机载UWB SAR成像处理。 相似文献
78.
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
79.
80.
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