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81.
结合天津电力公司供用电大厦方案设计,强调在滨水地区建筑设计中应寻求建筑与环境的协调,寻求对自然环境因素的充分利用,突出滨水特点。 相似文献
82.
根据三电源的设计依据和要求 ,主要介绍了两个市电电源的防并联联锁 ,互为备用的备件 ,柴油发电机与市电防误并网的联锁 ,低压电气主接线型式 ,柴油发电机自动控制原理。 相似文献
83.
为解决现有传动系疲劳寿命试验台能耗大的问题,研制开发了一种以直流测功电机为加载器、数字直流可逆调速器为控制器,将直流测功电机产生的电能回馈到电网的传动系疲劳寿命试验台。该装置的电能回馈率达76%左右,节能效果显著。 相似文献
84.
文章是以新一代中国建筑师的视角对2006年6月至9月荷兰鹿特丹“中国当代”建筑展的一次观察,作者对本次展览的文化背景和策展方式与1997年纽约的“从内到外”展和2005年的深圳的“城市开门”展做了比较,在从多重角度讨论本次展览的策展态度、布展设计、和关注点的同时,文章反思了策展人费拉森罗德提出的种种关于骤变中的中国城市与建筑的关键问题。 相似文献
85.
86.
权宜建筑--青年建筑师与中国策略 总被引:7,自引:0,他引:7
文章试图在杨永生先生关于四代建筑师划分的基础上分出第五代青年建筑师,分析他们所受的影响,以及应对当代中国特定问题时的独特策略。并将这种中国特殊条件下发展出的“权宜建筑”的策略看作中国创造性地接受并改造西方建筑模式而发展出的具有当代中国特征的建筑文化。 相似文献
87.
88.
《Journal of the European Ceramic Society》2022,42(9):3913-3919
Artificially tilted multilayer thermoelectric devices (ATMTDs) have attracted growing attention due to their ease in miniaturization and high flexibility in device design. However, most of these devices are inefficient due to the lack of effective strategy to optimize their material matching and geometrical configurations. Herein, a high-throughput optimization approach is employed to screen high-performance Bi2Te2.7Se0.3-based ATMTDs from a material genome database covering 230 kinds of candidates. 14 kinds of ATMTDs are found to have ZTzx,max values exceeding 0.3 and tilt angles greater than 15°. Bi0.1Sb1.9Te3/Bi2Te2.7Se0.3 ATMTD is screened out and fabricated because of its excellent transverse figure of merit, large tilt angle, and good interface compatibility. Consequently, transverse figure of merit over 0.3, thermal sensitivity greater than 0.11 mV·K?1, and power density up to 1.1 kW·m?2 are recorded in Bi0.1Sb1.9Te3/Bi2Te2.7Se0.3 ATMTD. This indicates that ATMTDs have great potential for application in the fields of temperature detection and power generation. 相似文献
89.
P. Macías 《The Science of the total environment》2010,408(20):4511-4523
This paper presents an estimate of the externalities produced in the Mexico City Metropolitan Area (MCMA) through the impacts on health caused by secondary pollutants attributed to seven electric power plants located outside this area. An original method was developed to make possible a simplified application of the impact pathway approach to estimate the damage costs in the specified area. Our estimate shows that the annual costs attributed to secondary pollutants total 71 million USD (min/max 20/258 million USD). Finally, this paper discusses basic ideas on the implications for energy policy arising from this exercise in externality valuation. 相似文献
90.
Brazil’s electricity market is the largest in Latin America and the ninth largest in the world. It has been implemented as a mixed market in which regulated and deregulated contracting environments coexist. The volume of transactions in the deregulated market has experienced steep growth over the last few years and is expected to surpass the regulated market. Different programs to diversify the country’s energy matrix have been devised, especially by integrating intermittent renewable sources to address the deregulated market expansion. Consequently, such an energy policy path has prompted the need to increase the granularity of the Brazilian deregulated market’s spot price, namely the Difference Settlement Price (DSP). The DSP had been weekly defined accounting for three loading levels and four submarkets, and, as of 2021, it has been hourly defined accounting for four submarkets; the weekly DSP is inefficient in actually signaling prices based on ex-ante marginal cost of operation of the interconnected Brazilian power system. Besides such granularity alteration, Brazil has also undergone a severe hydrological crisis in 2021 that led to significantly lower water inflows into major hydrographic watersheds and, as a result, most hydroelectric power plant reservoirs hit a 91-year low. The described scenario is relevant in utility policies and energy economics since it depicts a significant paradigm shift experience in such a large electricity market. This study presents the first hourly DSP behavior analysis since its implementation in the Brazilian electricity market and explores its statistical characteristics and relationships with exogenous variables throughout 2021. Additionally, we discuss the hourly DSP’s volatility observed in the year 2021 and how it has resulted in price spikes. At last, we compare the behavior of the Brazilian hourly DSP with the energy prices of five other countries’ electricity markets. Despite being a significant market improvement, the DSP granularity increase per se could not accurately represent the actual marginal cost of operation over the year 2021 since, besides instabilities observed in the hourly DSP, market intervention mechanisms had to be applied by Brazilian regulatory agencies to minimize the hydrological crisis’ impacts. 相似文献