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51.
介绍了桃林口水库大坝人工监测项目管理软件研制的意义。对软件结构、开发环境、基本计算原理、主要功能进行了详细阐述;并以大坝垂直位移分析为例,详细讲述了回归分析在资料分析中的具体应用。该软件的应用使工程管理水平上了一个新台阶。 相似文献
52.
A Study of Shadowing on Indoor Visible-Light Wireless Communication Utilizing Plural White LED Lightings 总被引:3,自引:1,他引:2
Toshihiko Komine Shinichiro Haruyama Masao Nakagawa 《Wireless Personal Communications》2005,34(1-2):211-225
White LED is considered as a strong candidate for the future lighting technology. We have proposed an optical wireless communication
system that employs white LEDs for indoor wireless networks. In this system, LED is used not only as a lighting device, but
also as a communication device. The transmitter has large optical power and large emission characteristics to function as
lighting device. And the system has specific wireless channel impulse response differing from infrared wireless communication.
In this paper, we discuss about shadowing effect on the system utilizing plural LED lightings including the performance of
ISI based on the impulse response. We consider the downlink transmission based on TDMA and evaluate the shadowing effect caused
by pedestrians with computer simulation. When the shadowing often occurs at 800 Mb/s, the performance of outage call duration
rate and blocking rate are improved by using 3 LED lightings compared with 1 or 2 LED lightings. And, we show that the system
with the optimal number of the LED lighting is robust against shadowing and can accommodate more calls.
Toshihiko Komine was born in Shizuoka, Japan, on November 17, 1978. He received the B.E. and M.E. degrees in Information and Computer Science
from Keio University, Yokohama, Japan, in 2001 and 2003 respectively. He is currently studying for the Ph.D. degree at Department
of Information and Computer Science, Keio University. His current research interests are optical wireless communications and
LED communications.
Shinichiro Haruyama is a professor at Department of Information and Computer Science, Faculty of Science and Technology, Keio University, Yokohama,
Japan. He received an M.S. in engineering science from University of California at Berkeley in 1983 and a Ph.D. in computer
science from the University of Texas at Austin in 1990. He worked for Bell Laboratories of AT{&}T and Lucent Technologies,
U.S.A from 1991 to 1996, and for Sony Computer Science Laboratories, Inc. from 1998 to 2002. His research interests include
reconfigurable system, system design automation, wireless communication, and visible light communication.
Masao Nakagawa was born in Tokyo, Japan in 1946. He received the B.E., M.E. and Ph.D. degrees in electrical engineering from Keio University,
Yokohama, Japan, in 1969, 1971 and 1974 respectively. Since 1973, he has been with the Department of Electrical Engineering,
Keio University, where he is now a Professor. His research interests are in CDMA, consumer Communications, Mobile communications,
ITS (Intelligent Transport Systems), Wireless Home Networks, and Visible light Communication. He received 1989 IEEE Consumer
Electronics Society Paper Award, 1999-Fall Best Paper Award in IEEE VTC, IEICE Achievement Award in 2000, IEICE Fellow Award
in 2001. He was the executive committee chairman on International Symposium on Spread Spectrum Techniques and Applications
in 1992 and the technical program committee chairman of ISITA (International Symposium on Spread Spectrum Techniques and Applications)
in 1994. He is an editor of Wireless Personal Communications and was a guest editor of the special issues on “CDMA Networks
I, II, III and IV” published in IEEE JSAC in 1994 (I and II) and 1996 (III and IV). He chairs the Wireless Home Link sub-committee
in MMAC (Multimedia Mobile Access Communication Promotion Committee). 相似文献
53.
54.
通过实例,对管理信息系统的功能模块、关系数据库进行了分析、设计和实现,并总结了其实现过程中的有关技巧。 相似文献
55.
56.
The paper presents a derivation of the dynamic impedance of a PV module. At each bias voltage, the general form of the impedance describes a semicircular locus in the complex impedance plane. Intercepts of each impedance locus yield series, shunt and dynamic resistance of a module. Determinations of the dynamic impedance of a x-Si PV module in the dark with five reverse bias voltages and over a frequency range of 1 Hz to 60 kHz are made. The experimental results validate the derived general form of dynamic impedance. 相似文献
57.
58.
叙述了利用MS-EXCEL通用电子表格软件中的规划求解模块优化油品调合的方法,并以汽油调合为例,说明构造数学模型的方法,以及实施优化求解的具体过程。 相似文献
59.
根据我国专利法的原则,在对我国催化重整和芳烃生产专利检索过程和结果进行分析的基础上,阐述了对目前我国催化重整工艺专利市场的几点看法并提出对策。 相似文献
60.