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991.
介绍了中波和长波“红外小光点扫描测试系统”。该系统由红外聚焦光学子系统,六维精密扫描工件台及数据采集子系统构成。可用于红外焦平面器件重要性能参数如串音、响应均匀性、转移效率的测量,也可用于单元红外探测器有效响应面积和响应均匀性等参数的测量。 相似文献
992.
介绍了多阳极微道板阵列(MAMA)紫外探测器系统的最新结构与性能,以及高增益MCP工作的基本特性,并给出了对各类高增益MCP测试的结果。 相似文献
993.
采用有限深对称方势阱近似模型求解薛定谔方程得到Ge/Si量子阱中的子能级分布,并基于迭代法数值求解泊松方程模拟计算了量子阱结构样品在不同偏压下的载流子浓度分布和C-V特性.C-V曲线上电容平台的存在是量子阱结构C-V特性的显著特征,它与量子阱结构参数有密切的关系.随着覆盖层厚度的减小,C-V曲线上平台起始点的电容值增加,并且向低电压方向移动直至其消失.随着量子阱中的掺杂浓度提高,阱中的载流子浓度也会相应增加,那就需要更高的外加电压才能耗尽阱中的载流子,因此平台宽度也就随着掺杂浓度的增加而增加.当覆盖层厚度增加时,由于电压的分压作用,使得降在量子阱上的分压相应减少,因此需要更大的外加偏压才能使阱中载流子浓度全部耗尽,这就使平台的宽度增大.同样地,当覆盖层掺杂浓度增加时,覆盖层中更多的载流子转移到阱内,也就需要更高的外加偏压才能使阱中载流子全部耗尽,平台的宽度也就随之增大. 相似文献
994.
995.
Ju Huang Quan Liu Jian‐Hua Zou Xu‐Hui Zhu Ai‐Yuan Li Jun‐Wen Li Sha Wu Junbiao Peng Yong Cao Ruidong Xia Donal D. C. Bradley Jean Roncali 《Advanced functional materials》2009,19(18):2978-2986
Soluble molecular red emitters 1a / 1b are synthesized by Stille coupling from 2‐(3,5‐di(1‐naphthyl)phenyl)thiophene precursors. The compounds show emission maxima at ca. 610 nm in CH2Cl2 solution and 620 nm in solid films. Replacing the n‐hexyl substituent by 4‐sec‐butoxyphenyl produces a marked increase of glass transition temperature (Tg) from 82 °C to 137 °C and increases the solubility in toluene and p‐xylene, thus improving the film‐forming properties. Cyclic voltammetry shows that the compounds can be reversibly oxidized and reduced around +1.10 and ?1.20 V, respectively. A two‐layered electroluminescent device based on 1b produces a pure red light emission with CIE coordinates (0.646, 0.350) and a maximal luminous efficiency of 2.1 cd A?1. Furthermore, when used as a solution‐processed red emitter in optically pumped laser devices, compound 1b successfully produces a lasing emission at ca. 650 nm. 相似文献
996.
997.
矿用隔爆型变频器散热方式的选择 总被引:2,自引:0,他引:2
根据变频器功率和使用环境的不同,为矿用隔爆型变频器提出几种适合的散热方式。 相似文献
998.
Ca4GdO(BO3)3(GdCOB)是一种新型的自倍频晶体.利用氙灯作泵浦源,对单掺的Nd∶GdCOB和双掺的Cr∶Nd∶GdCOB两种自倍频晶体实现了1061nm~530.5nm自由运转的自倍频转换.单掺和双掺晶体的泵浦阈值能量分别为1.0J和0.92J,自倍频光的最大输出能量分别为1.96mJ和2.46mJ.利用脉冲染料激光作泵浦源,对Nd∶GdCOB晶体获得了1331nm基频光和655nm自倍频红光运转,并获得了530.5nm自倍频绿光输出. 相似文献
999.
Wei-Zen Chen Guan-Sheng Huang 《IEEE transactions on circuits and systems. I, Regular papers》2008,55(6):1495-1501
1000.
Sensor nodes are densely deployed to accomplish various applications because of the inexpensive cost and small size. Depending
on different applications, the traffic in the wireless sensor networks may be mixed with time-sensitive packets and reliability-demanding
packets. Therefore, QoS routing is an important issue in wireless sensor networks. Our goal is to provide soft-QoS to different
packets as path information is not readily available in wireless networks. In this paper, we utilize the multiple paths between
the source and sink pairs for QoS provisioning. Unlike E2E QoS schemes, soft-QoS mapped into links on a path is provided based
on local link state information. By the estimation and approximation of path quality, traditional NP-complete QoS problem
can be transformed to a modest problem. The idea is to formulate the optimization problem as a probabilistic programming,
then based on some approximation technique, we convert it into a deterministic linear programming, which is much easier and
convenient to solve. More importantly, the resulting solution is also one to the original probabilistic programming. Simulation
results demonstrate the effectiveness of our approach.
This work was supported in part by the U.S. National Science Foundation under grant DBI-0529012, the National Science Foundation
Faculty Early Career Development Award under grant ANI-0093241 and the Office of Naval Research under Young Investigator Award
N000140210464.
Xiaoxia Huang received her BS and MS in the Electrical Engineering from Huazhong University of Science and Technology in 2000 and 2002,
respectively. She is completing her Ph.D. degree in the Department of Electrical and Computer Engineering at the University
of Florida. Her research interests include mobile computing, QoS and routing in wireless ad hoc networks and wireless sensor
networks.
Yuguang Fang received a Ph.D. degree in Systems Engineering from Case Western Reserve University in January 1994 and a Ph.D degree in
Electrical Engineering from Boston University in May 1997. He was an assistant professor in the Department of Electrical and
Computer Engineering at New Jersey Institute of Technology from July 1998 to May 2000. He then joined the Department of Electrical
and Computer Engineering at University of Florida in May 2000 as an assistant professor, got an early promotion to an associate
professor with tenure in August 2003 and to a full professor in August 2005. He holds a University of Florida Research Foundation
(UFRF) Professorship from 2006 to 2009. He has published over 200 papers in refereed professional journals and conferences.
He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator
Award in 2002. He has served on several editorial boards of technical journals including IEEE Transactions on Communications,
IEEE Transactions on Wireless Communications, IEEE Transactions on Mobile Computing and ACM Wireless Networks. He have also
been activitely participating in professional conference organizations such as serving as The Steering Committee Co-Chair
for QShine, the Technical Program Vice-Chair for IEEE INFOCOM’2005, Technical Program Symposium Co-Chair for IEEE Globecom’2004,
and a member of Technical Program Committee for IEEE INFOCOM (1998, 2000, 2003–2007). 相似文献