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Indoor thermal comfort research on the hybrid system of radiant cooling and dedicated outdoor air system

Weiliang WANG, Zhe TIAN

《能源前沿（英文）》 2013年第7卷第2期页码 155-160 doi: 10.1007/s11708-013-0244-z

摘要： The radiant cooling system generally operates with the dedicated outdoor air system (DOAS). Air supply modes and the corresponding setting parameters of the hybrid system may substantially influence the indoor thermal comfort. With target indexes of air diffusion performance index (ADPI) and predicted mean vote (PMV), the Taguchi method was used to choose the optimal air supply mode and to analyze the significance of different factors on the thermal comfort. The results are expected for conducting the future design and regulation of the hybrid system. Computation fluid dynamics (CFD) simulation as well as verified experiments was performed during the research. Based on the ADPI studies, it is found that the air supply mode of ceiling delivery with ceiling exhaust is an optimized option to apply in DOAS of the hybrid system. Variance analysis results show that influence fact of air supply temperature is the most dominant one to impact the indoor thermal comfort index of PMV.

关键词： radiant cooling system dedicated outdoor air system (DOAS) thermal comfort Taguchi method variance analysis

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A glance of excellence in chemical science and engineering at Tianjin University: A special issue dedicated

《化学科学与工程前沿（英文）》 2015年第9卷第3期页码 259-261 doi: 10.1007/s11705-015-1537-z

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致力于创新与发展的中国石化工程建设公司

null

《中国工程科学》 1999年第1卷第2期页码 97-98

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Toward a nonlinear control of an AC-DC-PWM converter dedicated to induction heating

Amel HADRI-HAMIDA, S. ZEROUALI, A. ALLAG

《能源前沿（英文）》 2013年第7卷第2期页码 140-145 doi: 10.1007/s11708-013-0243-0

摘要： In this paper, a nonlinear control strategy applied to an AC-DC-pulse width modulation (PWM) converter is developed and simulated. First a nonlinear system modeling is derived with state variables of the input current and the output voltage by using power balance of the input and output. The system is linearized and decoupled, and then a state feedback law is obtained. For robust control of parameter perturbation, integrators are added to the exact feedback control law. The simulation is provided to verify the validity of the control algorithm.

关键词： DC-DC converter AC-DC-pulse width modulation (PWM) converter induction heating nonlinear control

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不辱历史使命致力民族强盛的中国工程物理研究院

《中国工程科学》 2001年第3卷第8期页码 91-92

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Modeling and control of a permanent magnet synchronous generator dedicated to standalone wind energy

Louar FATEH,Ouari AHMED,Omeiri AMAR,Djellad ABDELHAK,Bouras LAKHDAR

《能源前沿（英文）》 2016年第10卷第2期页码 155-163 doi: 10.1007/s11708-016-0410-1

摘要： The interest for the use of renewable energies has increased, because of the increasing concerns of the environmental problems. Among renewable energies, wind energy is now widely used. Wind turbines based on an asynchronous generator with a wound rotor present the inconvenience of requiring a system of rings and brooms and a multiplier, inferring significant costs of maintenance. To limit these inconveniences, certain manufacturers developed wind turbines based on synchronous machines with large number of pairs of poles coupled directly with the turbine, avoiding using the multiplier. If the generator is equipped with permanent magnets, the system of rings and brooms is eliminated. The control of the permanent magnet synchronous generator (PMSG) can be affected with the implementation of various techniques of control. This paper presented a new approach mainly based on the control strategy of power production system based on the PMSG. In fact, a mathematical model that simulates the Matlab chain was established with the introduction of control techniques, such as direct control of the torque (DTC) to control the load side converter (LSC), the control of the speed of the turbine and the DC-bus voltage ensured by PI regulators. To show the performance of the correctors used, some simulation results of the system were presented and analyzed.

关键词： wind turbine permanent magnet synchronous generator (PMSG) converter proportional-integral (PI) control direct control of the torque (DTC) regulation

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Life cycle analysis and choice of natural gas-based automotive alternative fuels in Chongqing Municipality, China

WU Rui, LI Guangyi, ZHANG Zongyi, REN Yulong, HAN Weijian

《环境科学与工程前沿（英文）》 2007年第1卷第3期页码 292-298 doi: 10.1007/s11783-007-0049-6

摘要： Road transport produces significant amounts of emissions by using crude oil as the primary energy source. A reduction of emissions can be achieved by implementing alternative fuel chains. The objective of this study is to carry out an economic, environmental and energy (EEE) life cycle study on natural gas-based automotive fuels with conventional gasoline in an abundant region of China. A set of indices of four fuels/vehicle systems on the basis of life cycle are assessed in terms of impact of EEE, in which natural gas produces compressed natural gas (CNG), methanol, dimethylether (DME) and Fischer Tropsch diesel (FTD). The study included fuel production, vehicle production, vehicle operation, infrastructure and vehicle end of life as a system for each fuel/vehicle system. A generic gasoline fueled car is used as a baseline. Data have been reviewed and modified based on the best knowledge available to Chongqing local sources. Results indicated that when we could not change electric and hydrogen fuel cell vehicles into commercial vehicles on a large scale, direct use of CNG in a dedicated or bi-fuel vehicle is an economical choice for the region which is most energy efficient and more environmental friendly. The study can be used to support decisions on how natural gas resources can best be utilized as a fuel/energy resource for automobiles, and what issues need to be resolved in Chongqing. The models and approaches for this study can be applied to other regions of China as long as all the assumptions are well defined and modified to find a substitute automotive energy source and establish an energy policy in a specific region.

关键词： dedicated primary economic alternative abundant

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客运专线无砟轨道铁路线下结构沉降变形观测与评估技术

李明领

《中国工程科学》 2009年第11卷第1期页码 48-59

摘要：

为满足高速列车安全、舒适性的需要，保证线路的高平顺性，无碴轨道的铺设与运营对路基、桥涵、隧道等线下结构的工后沉降要求非常严格, 追求“零沉降”理念。以武广铁路客运专线为基础，系统地介绍了线下结构物沉降变形观测关键技术，数据管理与分析预测系统，提出了工后沉降的预测方法及评估条件与标准，合理确定无碴轨道开始铺设时间，以保证客运专线无碴轨道结构铺设的质量。并提出了一些体会和建议，为正在建设的无砟轨道客运专线提供借鉴。

关键词：客运专线无砟轨道沉降变形观测分析评估无碴轨道铺设条件