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101.
为了对热电联产之中电负荷与热负荷变化进行协调,需对热电供需的不均衡问题进行处理,优化分布式能源的系统之中燃气轮机的热电联产运行方式.同时在传统以热定电与以电定热运行基础上,添加辅助的设备方式,对热电联产运行方式进行补充.本文主要分析了燃气轮机的热电联产两类运行方式,深入研究优化分布式能源的系统之中燃气轮机的热电联产运行方式,为相关研究提供参考. 相似文献
102.
103.
Volkan?KursunEmail author Siva?G.?Narendra Vivek?K.?De Eby?G.?Friedman 《Analog Integrated Circuits and Signal Processing》2005,44(3):231-238
A CMOS OTA-C low-pass notch filter for EEG application is described. The pass-band covers four bands of brain wave and provides
more than 65 dB attenuation for the 50 Hz power line interference. The OTA works in the weak inversion region and a low transconductance
of 3 nA/V is achieved. The low transconductance enables using small capacitors in the OTA-C filter so that the filter is suitable
for the multi-channel EEG integrated circuits. The measured results show the good performance of the filter for filtering
the noise in acquired EEG signals.
Xinbo Qian received the B.Sc. degree from Beijing Institute of Technology, P.R. China, in 1991 and M.Sc. degree from Institute of Physics,
Chinese Academy of Sciences, in 1996. From 1996 to 1999, she was a research engineer in the Institute of Acoustics, Chinese
Academy of Sciences, worked on the sonar signal receiving and processing systems. Since 1999, she has been pursuing the Ph.D.
degree in Electrical and Computer Engineering department, National University of Singapore, with research direction on on-chip
readout circuits for microbolometer focal plane arrays. Now she is employed by Department of Mechanical Engineering and Division
of Bioengineering, National University of Singapore as a research fellow. Her research interest is low-noise integrated circuits
design and bio-medical sensor electronics, including electroencephalography IC, magnetocardiography IC, low-noise amplifier,
filter and data converters etc.
Yong Ping Xu graduated from Nanjing University, P.R. China in 1977. He received his Ph.D. from University of New South Wales (UNSW) Australia,
in 1994. From 1978 to 1987, he was with Qingdao Semiconductor Research Institute, P.R. China, initially as an IC design engineer,
and later the deputy R&D manager and the Director. From 1989 to 1992, he was working on silicon diode based infrared detectors
towards his Ph.D. at School of Electrical Engineering, UNSW Australia. From 1993 to 1995, he worked on an industry collaboration
project with GEC Marconi, Sydney, Australia, at the same university, involved in design of sigma-delta ADCs. He was a lecturer
at University of South Australia, Adelaide, Australia from 1996 to 1998. He has been with the Department of Electrical and
Computer Engineering, National University of Singapore since June 1998 and is now an Associate Professor. His general research
interests are in the areas of mixed-signal and RF integrated circuits, and integrated MEMS and sensing systems. His current
focuses are high-speed wideband ADC, UWB front-end circuits and low-power low-voltage integrated circuits for biomedical applications.
He is a Senior Member of IEEE.
Xiaoping Li received his Ph.D. degree from Department of Mechanical and Manufacturing Engineering, University of New South Wales, Australia
in 1991, and joined the National University of Singapore in 1992, where he is currently an Associate Professor with the Department
of Mechanical Engineering and Division of Bioengineering. He was a visiting professor of Tokyo Institute of Technology, Japan
in 2000, and visiting professor of Georgia Institute of Technology, USA in 2001. He is a member of American Society of Mechanical
Engineers (ASME), a senior member of Society of Manufacturing Engineering (SME) and a senior member of North American Manufacturing
Research Institute/SME, and is currently the Chairman of SME Singapore Chapter. His current research interests include neurosensors
and nanomachining. He is a guest editor of International Journal of Computer Applications in Technology, USA. He is a regular
reviewer of the ASME Journal of Manufacturing Engineering, USA, Transactions of NAMRI/SME, USA, Journal of materials processing
technology, UK, International Journal of Machine Tools and Manufacture, UK, and IMechE Journal of Engineering Manufacture,
UK. 相似文献
104.
电流模带隙基准源(CMBGR)在低电源电压电路中得到广泛的应用,但其启动行为仍值得关注。在启动电路不可靠的情况下,CMBGR会导致芯片失效,使得成品率下降。在分析CMBGR的启动和多个工作点问题后,提出一种只有两个稳定工作点的CMBGR,可通过监测电路状态和控制启动电路的充电来解决简并点问题。采用0.13 μm CMOS工艺,对提出的GMBGR电路进行设计与仿真。仿真结果表明,该电路产生的参考电压小于1.25 V,在-25 ℃~125 ℃之间的温度系数为4.7×10-6/℃,具有良好的启动性能。 相似文献
105.
106.
107.
目前逆合成孔径雷达(ISAR)在军事上的作用越来越突出,是目标分类、辨识和战场上敌我识别以及精确制导强有力的手段,在未来防空和导弹防御系统中具有十分重要的作用。本文分析了ISAR成像原理,建立了ISAR系统的仿真模型,并在此基础上对几种干扰技术进行了仿真。 相似文献
108.
本文提出了一种无需检测电感电流及其过零点的简单数字控制方案,实现了临界连续模式功率因数校正器的控制。取得了功率开关管的ZVZCS,消除了整流二极管和快恢复二极管的反向恢复带来的损耗,提高了变换器的效率和可靠性;另外,数字控制器克服了模拟IC控制器的开关频率限制问题,消除了输入电流的低频畸变,提高了功率因数;同时,也降低了输入电感的值,降低了成本的同时提高了功率密度。为实现中小功率数字控制功率因数校正器的产品化提供了一个良好的解决方案。 相似文献
109.
为了控制对发光二极管(LED)显示屏亮度调制时电 源电流产生的电磁干扰(EMI),对3种脉冲宽度调制(PWM)调光方法下显示 屏的电源电流频谱进行了研究。首先比较了线性、离散和选通3种PWM的调光原理和潜在 EMI,设计了基于电流频谱分析的EMI评估法,并通过对单亮度和亮度均匀渐变图像 的仿真,验证了评 估法的有效性;最后通过对LED显示屏真实图像显示时的电流频谱分析,比较了3种调光方 法的潜在EMI。实验结果表明:线性PWM方式下,同时点亮LED会产生较大的EMI;离 散PWM对消耗电流的 延展和码制对消作用,可以有效地减小EMI;选通PWM随着选通等级的提高,最小点 亮脉冲变窄不利 于减小EMI。本文的分析结果可用于在LED显示屏产品设计时,合理进行EMI分析 与分配,预估产品的电磁兼容性。 相似文献
110.
TMS320VC5402的高性能、低功耗特点使其广泛适用于需要脱机运行的内嵌式系统。为实现脱机运行,其片内掩膜ROM带有一个引导装载程序bootloader,可以实现对用户程序的多种引导装载。文中介绍了TMS320VC5402片内bootloader的引导原理,给出了并行引导方式的设计方案。 相似文献