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71.
低工作温度的氧化钨气敏材料 总被引:3,自引:0,他引:3
本文报道了一种可以在100℃左右工作的氢化钨气敏材料,它对氢气和一氧化氮有很高的灵敏度和良好的选择性,并可对空气中的一氧化氮进行探测 相似文献
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73.
提出了一种新型的组合式光纤流量传感器,介绍了它的工作原理,详细讨论了光脉冲转换器的设计要点,据此设计了传感头,并给出了它的实验结果。 相似文献
74.
压力传感器的应力计算 总被引:2,自引:0,他引:2
从弹性力学的板壳理论出发,对不同参数的凸型板结构形变膜受压后的应力分布作了近似计算,为高线性度SOI压力传感器的芯片设计提供了理论指导。用BESOI技术研制的凸型板结构集成压力传感器的非线性度达0 09%,样品灵敏度的实测值与应力计算理论值的差别约17%。 相似文献
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Joseph Dunn Michael Neufeld Anmol Sheth Dirk Grunwald John Bennett 《Mobile Networks and Applications》2006,11(1):37-45
Many companies, organizations and communities are providing wireless hotspots that provide networking access using 802.11b wireless networks. Since wireless networks are more sensitive to variations
in bandwidth and environmental interference than wired networks, most networks support a number of transmission rates that
have different error and bandwidth properties. Access points can communicate with multiple clients running at different rates,
but this leads to unfair bandwidth allocation. If an access point communicates with a mix of clients using both 1 Mb/s and
11 Mb/s transmission rates, the faster clients are effectively throttled to 1 Mb/s as well. This happens because the 802.11
MAC protocol approximate “station fairness”, with each station given an equal chance to access the media. We provide a solution
to provide “rate proportional fairness”, where the 11 Mb/s stations receive more bandwidth than the 1 Mb/s stations. Unlike
previous solutions to this problem, our mechanism is easy to implement, works with common operating systems and requires no
change to the MAC protocol or the stations.
Joseph Dunn received an M.S. in computer science from the University of Colorado at Boulder in 2003, and B. S. in coputer science and
mathematics from the University of Arizona in 2001. His research interests are in the general area of computer systems, primarily
focusing on security and scalability in distributed systems. He is currently working on his Ph.D. in computer science from
the University of Colorado at Boulder.
Michael Neufeld received a Ph.D. in Computer Science from the University of Colorado at Boulder in December of 2004, having previously received
an M.S. in Computer Science from the University of Colorado at Boulder in 2000 and an A.B. in Computer Science from Princeton
University in 1993. His research interests are in the general area of computer system, specifically concentrating on wireless
networking, software defind/cognitive radio, and streerable antennas. He is currently a postdoc in the Computer Science department
at the University of Calorado at Boulder pursuing research related to software defined radio and new MAC protocols for steerable
phase array antennas.
Anmol Sheth is a Ph.D. student in Computer Science at the University of Colorado at Boulder. He received his B.S. in Computer Science
from the University of Pune, India in 2001. He has been co-leading the development of the MANTIS operating system. He has
co-authored three papers include MAC layer protocol design, energy-efficient wireless communication, and adapting communications
to mobility.
Dirk Grunwald received his Ph.D. from the University of Illinois in 1989 and joined the University of Colorado the same year. His work
addresses research and teaching in the broad area of “computer systems”, which includes computer architecture, operating systems,
networks, and storage systems. His interests also include issues in pervasive computing, novel computing models, and enjoying
the mountains. He is currently an Associate Professor in the Department of Computer Science and in Electrical and Computer
Engineering and is also the Director of the Colorado Center for Information Storage.
John Bennett is a Professor of Computer Science with a joint appointment in Electrical and Computer Engineering at the University of Colorado
at Boulder. He also serves as Associate Dean for Education in the College of Engineering and Applied Science. He joined the
CU-Boulder faculty in 2000, after serving on the faculty of Rice University for 11 years. While at Rice, Bennett pioneered
a course in engineering design for both engineering and non-engineering students that has been emulated at several universities
and high schools. In addition to other teaching awards, Bennett received the Keck Foundation National Award for Engineering
Teaching Excellence for his work on this course. Bennett received his Ph.D. in 1988 from the University of Washington. Prior
to completing his doctoral studies, he was a U.S. Naval Officer for several years and founded and served as President of Pacific
Mountain Research, Inc., where he supervised the design and development of a number of commercial computing systems. Bennett's
primary research interests are broadly focused in the area of distributed systems, and more narrowly in distributed information
management and distributed robotic macrosensors. 相似文献
77.
78.
The Video Server Estimator (VSE) is an analytical tool which allows a user to perform a cost/performance analysis of video servers with hierarchical storage. The underlying model comprises multiple systems, main memory, expanded storage, disks and a tape library. The main objective of the tool is to optimally allocate the video files to different storage media based on the system parameters and the video file request probability distribution. The cost and the size of the video server that can accommodate a customer profile are determined. Furthermore, the impact of design parameters on the cost and performance are examined through a parametric analysis. 相似文献
79.
光学和传感器的防护技术 总被引:1,自引:0,他引:1
近年来,光电技术发展异常迅速,在这些技术装备中,当用光学聚焦时,辐射能量对光学元件、探测器都会构成威胁。本文讨论辐射对光学和探测器的影响以及降低其影响的防护技术。 相似文献
80.