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排序方式: 共有311条查询结果,搜索用时 62 毫秒
101.
固态变压器作为能源互联网中实现能量转换和控制的关键设备,有很多方面需要进行深入研究,文章结合固态变压器的自身特点,对其主要发展的核心技术,包括基于SiC新型宽禁带材料的研制、基于SiC的固态功率器件和固态变压器设计与实现、固态变压器的先进控制策略研究等进行了详细阐述。 相似文献
102.
伴随高速可编程逻辑器件的广泛应用,实时快速可靠地对系统状态信号进行处理,实现对复杂机电系统运行状态的实时监控成为用户追求的目标。基于数字电位器由于可调精度高,控制方便,性能稳定等优点,给出了一种基于CPLD可编程器件,通过数字电位器实现在半实物仿真系统中对PT100热电阻的阻值变化进行等效模拟的工程应用。利用本研究内容,通过上位机界面对系统温度参数进行人工设定,即可轻易实现对PT100热电阻在不同温度下阻值的真实模拟,检验实际系统温度监测装置软硬件的可靠性,确保系统安全运行。 相似文献
103.
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
104.
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
105.
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
106.
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
107.
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
108.
Jonathan B. Tucker 《The Nonproliferation Review》2013,20(1):25-42
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
109.
后勤工程学院绿色建筑示范楼是“超低能耗”理论的实践成果。通过理论研究和对当地气候以及建筑能耗的现状分析,综合采用自然通风采光技术、墙体自保温技术、建筑自遮阳设计等被动式节能技术,地源热泵应用、太阳能利用、楼宇智能控制等主动式节能技术,对示范楼进行了设计、建造。经过两年多的使用,各项节能数据的测定表明:示范楼节约能耗75.4%,实现了公共建筑超低能耗的节能要求。 相似文献
110.
针对阀控式海水淡化能量回收装置增泄压过程中压力波动和浓盐水海水掺混导致反渗透膜组件工作负担变大的问题,对增压容器和增压过程建立模型,使用流体力学软件Fluent仿真增压过程,得到了增压过程液压缸内部流域的压力和速度分布。探究了混合段液柱活塞的形成过程和长度变化,通过对比液压缸结构和进水口流速变化对混合程度的影响,给出了用混合段做液柱活塞的参数特性和适用性,为海水淡化系统余压能回收设计提供依据。 相似文献