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81.
以UniGear type ZS3.2型铠装式金属封闭开关设备为例,详细阐述了普通35kV开关设备经过科学的工频耐压和雷电冲击耐压试验,通过绝缘加强及元器件的修改,使之安全可靠地在高原地区使用。并缜密筛选出一套先进的技术改造方案,同时展望了其市场应用前景。 相似文献
82.
This article employed a standard LCC to conduct economic analysis of upgrading the aging residential buildings in China. According to the current situation, an interest rate of 6%, an inflation rate of 3%, an increase rate of annual energy savings of 2% and an increase rate of electricity price of 2% were assumed in the method. The results indicated that only relying on gradually increasing electricity price and governments' subsidies was not enough. After detailed analysis of the energy saving measures and the distribution of all benefits from building energy retrofit, it was found that actually only 1/3 of original cost was spent only for energy savings, the second 1/3 for both energy savings and good façade appearance and occupants should share the last 1/3 because even if without energy retrofit, they would have to pay the part too. The corresponding results proved that the first 1/3 of investment cost could be drawn back within the residue life cycle, and so the investment could be accepted in a sheer market economy. In the end, a model about distribution of investment cost of and benefits was proposed to adapt the market economy to overcome the financial problems in China. 相似文献
83.
对某炼厂延迟焦化辐射进料泵的运行情况进行了分析,论证了切割叶轮、拆去个别叶轮、变频调速3种改造方案的优劣,发现实施拆除个别叶轮的方案较好,并按此法对某炼厂延迟焦化辐射进料泵实施改造,改造后泵性能完全可以满足生产要求,电机运行电流降低了10A,经济效益明显。最后提出了拆去个别叶轮与叶轮切割组合实施的方案最具经济性。 相似文献
84.
为研究扇形铅黏弹性阻尼器与加固框架结构之间的匹配关系及其对加固框架抗震性能的影响规律,用ABAQUS软件建立了对比空框架和加固框架的精细化有限元模型,结合试验试件骨架曲线及破坏形态验证了其合理性。提出扇形铅黏弹性阻尼器加固框架的综合设计原则,设定阻尼器扇形有效半径与框架柱净高之比为设计尺寸比,在此基础上,对不同设计尺寸比的加固框架进行对比分析。分析结果表明,合理设置的扇形铅黏弹性阻尼器可以显著提高加固框架的抗震性能,保护梁柱节点核心区;当设计尺寸比取值超过0.24时,会导致加固试件较早达到峰值荷载,但其后承载力又急剧衰减;建议扇形铅黏弹性阻尼器加固框架的设计尺寸比宜控制在0.1~0.2之间,实际设计中应依据不同加固需求选取相应的设计尺寸比。 相似文献
85.
Displacement‐dependent dampers with relatively low post‐yielding stiffness exhibits abrupt stiffness loss and can even induce notable damage concentrations under strong vibrations. A lattice‐shaped friction unit (LSFU) composed of steel strips and friction discs is proposed and it can dissipate most input energy through translational friction and rotational friction and provide post‐yielding stiffness through the axial strength of vertical strips. Measurements of the friction coefficient and torque coefficient ratio and quasi‐static analysis of the LSFU are conducted, the results indicate that the ratio rises first and then drops to a constant value. Under cyclic loading, the two friction mechanisms could work together effectively and the contribution of each component contained in the restoring force could be controlled by adjusting design parameters of the LSFU; the assembly accuracy of the components affect the resistance of vertical strips. The experiment results of two specimens are compared with those obtained from the developed formulas and numerical simulations. A design procedure and applicable style are proposed. Nonlinear seismic response analysis results show that these devices can reduce the displacement response effectively under small and moderate earthquakes and can also prevent concentrated damage and weak‐story occurrence in the structure relative to friction‐damped brace frame in strong earthquakes. 相似文献
86.
通过4根短柱(1根RC方柱和3根钢管自密实混凝土加固柱)的偏心受压试验,研究外套钢管自密实混凝土加固法对RC方柱承载力和延性性能的影响,结果表明加固后RC柱的承载力与延性得到大幅提高,且加固柱的承载力随偏心距的增大而减小。为进一步研究钢管壁厚和后浇混凝土强度对加固效果的影响,采用了通用有限元软件ANSYS对加固偏压柱的受力全过程进行了计算分析。经验证,计算所得试件的荷载-变形曲线与试验结果吻合良好。在此基础上对加固柱进行参数分析研究,研究结果表明:偏心距对加固偏压柱的承载力影响最为明显,其次是钢管壁厚,自密实混凝土强度的影响较小。 相似文献
87.
To benefit and protect the populace, government policies often promise aspirational changes to current practice. Different kinds of narratives are important in the framing, explanation, motivation, and understanding of policies and strategies. For example, the UK government's 2008 Climate Change Act proclaimed that all new homes will be zero carbon by 2016. This ‘hero story’, where society is ‘saved’ by clever technologies, is inspiring, positive and familiar. An alternative is the ‘learning story’, where things are not quite as simple as they first seemed. In a learning story, protagonists are normal people who need to overcome a challenge. In energy policy, the learning story could address the gap between the technical potential and what is achieved in practice. Three real-world examples from retrofit and new-build projects are used to show how implicit narratives can create conflict when the tellers (e.g. researchers) have to tell one kind of story but have data for the other. Recommendations are provided for a balanced approach to the deployment of different kinds of tales by policy-makers, researchers, implementers and users. Harnessing the learning story and developing a ‘caring story’ could motivate policy-makers and the public to invest effort in building performance. 相似文献
88.
89.
说明尿素装置原料脱氢技术改造原理,介绍了湖北化肥脱氢改造过程,分析在不同工况下,脱氢系统效果不同的原因,提出了改进意见。 相似文献
90.
当前大学校园改扩建工程中存在着新旧建筑及建筑与环境如何协调的问题,本文以辽宁科技大学新校区的扩建及旧建筑的改造为例,通过理论研究和实例剖析,总结归纳了处理大学校园新旧建筑关系及建筑与环境相互协调的5种手法:确立中心、协调、对比、存留及整合景观与环境。本文结论进一步丰富和提高处理新旧建筑与校园环境协调方面的经验和手法,可为广大关注大学校园建设问题的相关人员提供借鉴和参考。 相似文献