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111.
晶体硅薄膜电池制备技术及研究现状 总被引:2,自引:0,他引:2
晶体硅薄膜太阳电池近些年来得到广泛的研究和初步的商业化探索。根据所采用的晶体硅薄膜沉积工艺中温度范围的不同,晶体硅薄膜电池研究可分为高温路线和低温路线两个不同发展方向。本文分别从这两个方向综述了目前国外晶体硅薄膜电池制备技术的最新进展,最新实验室研究结果。报导了晶体硅薄膜电池商业化进展状况,指出了晶体硅薄膜电池实现产业化必须解决的问题。 相似文献
112.
洋葱路由技术在公网上提供双向、实时的匿名通信,其面向连接和严格的源路由方式导致效率低、扩展性差。利用分布式的概念,采用分段连接技术思想提出了一种安全、高效的分布式洋葱路由机制(DORS),给出了DORS路由实现算法,并从方案实现效率、安全性方面对DORS进行了分析。分析结果表明DORS具有良好的扩展性、鲁棒性、简单性和有效性。 相似文献
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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
116.
三峡—葛洲坝梯级枢纽常规水库调度系统是《长江三峡水利枢纽梯级水库调度自动化系统》的高级应用部分,该系统建立在三峡梯级水利枢纽水库调度自动化系统水调数据平台之上,在洪水预报成果的基础上,根据三峡—葛洲坝梯级枢纽的防洪、发电、航运的综合利用要求,作出三峡、葛洲坝电厂长、中、短期出力预报,相应作出梯级枢纽水库调度计划,确定梯级水库的蓄泄对策及闸门的开启计划,制定闸门的操作命令,完整地实现了三峡—葛洲坝梯级枢纽常规水库调度业务。 相似文献
117.
UV法测定聚甲基丙烯酸酯纳米粒中胰岛素的包封率 总被引:3,自引:0,他引:3
建立一种简便易行的测定聚甲基丙烯酸酯胰岛素纳米粒中游离胰岛素含量方法.用Nanosep OD100C33超滤膜分离纳米粒和游离药物,在276 nm处测定药物的吸光度,建立胰岛素含量测定方法,并对线性、回收率、精密度等指标进行考察,最后测定各种胰岛素和载体比例混合的纳米粒的包封率.结果发现,该超滤膜能较好地分离纳米粒和游离的药物,在0.11~1.10 u/mL范围内,药物在276 nm的吸光度和浓度存在良好的线性关系(r=0.999 8),线性方程为A=0.868 8C-0.001 6,高、中、低3种浓度的回收率和精密度良好.该方法操作简单、结果可靠,可用于胰岛素纳米粒中药物包封率的测定. 相似文献
118.
119.
Chenn-Jung Huang Wei-Kuang Lai Sheng-Yu Hsiao Hao-Yu Liu Rui-Lin Luo 《International Journal of Wireless Information Networks》2004,11(3):131-146
In this paper, a routing protocol which utilizes the characteristics of Bluetooth technology is proposed for Bluetooth-based mobile ad hoc networks. The routing tables are maintained in the master devices and the routing zone radius for each table is adjusted dynamically by using evolving fuzzy neural networks. Observing there exists some useless routing packets which are helpless to build the routing path and increase the network loads in the existing ad hoc routing protocols, we selectively use multiple unicasts or one broadcast when the destination device is out of the routing zone radius coverage of the routing table. The simulation results show that the dynamic adjustment of the routing table size in each master device results in much less reply time of routing request, fewer request packets and useless packets compared with two representative protocols, Zone Routing Protocol and Dynamic Source Routing. 相似文献
120.