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71.
电网无功补偿方式的探讨 总被引:1,自引:0,他引:1
概述了电网无功补偿的基本情况,并对几种无功补偿方式进行了技术分析,结合几种补偿方式的特点,提出了无功补偿配置原则。 相似文献
72.
73.
Palogue油田复合油藏动态响应及特征描述 总被引:1,自引:1,他引:0
以简单的复合油藏模型理论和方法为基础,以Palogue油田的实际测试井为例,介绍了复合油藏模型的试井动态识别与模型拟合,及与地质静态资料相结合的油藏综合描述过程.该描述方法将会对实际试井解释和油藏综合描述工作有所借鉴和帮助. 相似文献
74.
单片机软件模拟SPI接口的解决方案 总被引:3,自引:0,他引:3
SPI接口是一种同步串行通讯接口,具备SPI接口的外围芯片十分丰富,应用非常广泛。但是,具备SPI接口的单片机种类较少。介绍了一种基于单片机的模拟SPI接口的方法,使没有SPI接口的单片机扩展带有SPI接口的外围芯片成为现实。 相似文献
75.
This paper introduces an analytical model to investigate the energy efficiency of the IEEE 802.11 distributed coordinated
function (DCF). This model not only accounts for the number of contending nodes, the contention window, but also the packet
size, and the channel condition. Based on this model, we identify the tradeoff in choosing optimum parameters to optimize
the energy efficiency of DCF in the error-prone environment. The effects of contention window and packet size on the energy
efficiency are examined and compared for both DCF basic scheme and DCF with four-way handshaking. The maximum energy efficiency
can be obtained by combining both the optimal packet size and optimal contention window. To validate our analysis, we have
done extensive simulations in ns-2, and simulation results seem to match well with the presented analytical results.
The Ohio Board of Regents Doctoral Enhancements Funds and the National Science Foundation under Grant CCR 0113361 have supported
this work.
Xiaodong Wang received his B.S. degree in communication engineering from Beijing Information Technical Institute of China in 1995, and
his M.S. degree in electric engineering from Beijing University of Aeronautics and Astronautics of China in 1998. He joined
China Telecom in 1998 where he worked on communication protocols for telecommunication. From June 2000 to July 2002, he worked
on GSM base station software development at Bell-labs China, Beijing, China. Currently he is a Ph.D. student in Computer Engineering
at University of Cincinnati. His research activities include wireless MAC protocols, energy saving for wireless sensor networks.
He is a student member of the IEEE.
Jun Yin received the BS degree in automatic control from Dalian Railway Institute of China in 1997, and the MS degree in flight control
from Beijing University of Aeronautics and Astronautics of China in 2001. Since 2001 she has been a Ph.D. student in the OBR
Research Center for Distributed and Mobile Computing at the University of Cincinnati. Her research interests include performance
evaluation of 802.11 MAC protocol, wireless ad hoc networks and sensor networks. She is a student member of the IEEE.
Dharma P.Agrawal IEEE Fellow, 1987; ACM Fellow, 1998; AAAS Fellow, 2003 Dr. Agrawal is the Ohio Board of Regents Distinguished Professor of
Computer Science and Computer Engineering in the department of Electrical and Computer Engineering and Computer Science, University
of Cincinnati, OH. He has been a faculty member at Wayne State University, (1977–1982) and North Carolina State University
(1982–1998). He has been a consultant to the General Dynamics Land Systems Division, Battelle, Inc., and the U. S. Army. He
has held visiting appointment at AIRMICS, Atlanta, GA, and the AT&T Advanced Communications Laboratory, Whippany, NJ. He has
published a number of papers in the areas of Parallel System Architecture, Multi computer Networks, Routing Techniques, Parallelism
Detection and Scheduling Techniques, Reliability of Real-Time Distributed Systems, Modeling of C-MOS Circuits, and Computer
Arithmetic. His recent research interest includes energy efficient routing, information retrieval, and secured communication
in ad hoc and sensor networks, effective handoff handling and multicasting in integrated wireless networks, interference analysis
in piconets and routing in scatternet, use of smart directional antennas (multibeam) for enhanced QoS, Scheduling of periodic
real-time applications and automatic load balancing in heterogeneous workstation environment. He has four approved patents
and three patent filings in the area of wireless cellular networks. 相似文献
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80.
岩金矿山采空区处理现状及对策 总被引:1,自引:0,他引:1
岩金矿山以浅眼留矿法为代表的空场采矿法为主要开采手段,约占50%,每年形成数百万m^3采空区,并绝大多数未进行专门处理。本文介绍数例岩金矿山采空区处理方法及效果与对策,供有关企业参考。 相似文献