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991.
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
992.
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
993.
Wei-Zen Chen Guan-Sheng Huang 《IEEE transactions on circuits and systems. I, Regular papers》2008,55(6):1495-1501
994.
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
995.
Huang-Chung Cheng Fang-Shing Wang Chun-Yao Huang 《Electron Devices, IEEE Transactions on》1997,44(1):64-68
The NH3-plasma passivation has been performed on polycrystalline silicon (poly-Si) thin-film transistors (TFT's), It is found that the TFT's after the NH3-plasma passivation achieve better device performance, including the off-current below 0.1 pA/μm and the on/off current ratio higher than 108, and also better hot-carrier reliability than the H2-plasma devices. Based on optical emission spectroscopy (OES) and secondary ion mass spectroscopy (SIMS) analysis, these improvements were attributed to not only the hydrogen passivation of the defect states, but also the nitrogen pile-up at SiO2/poly-Si interface and the strong Si-N bond formation to terminate the dangling bonds at the grain boundaries of the polysilicon films. Furthermore, the gate-oxide leakage current significantly decreases and the oxide breakdown voltage slightly increases after applying NH3-plasma treatment. This novel process is of potential use for the fabrication of TFT/LCD's and TFT/SRAM's 相似文献
996.
Yuhua Cheng Min-Chie Jeng Zhihong Liu Jianhui Huang Mansun Chan Kai Chen Ping Keung Ko Chenming Hu 《Electron Devices, IEEE Transactions on》1997,44(2):277-287
A new physical and continuous BSIM (Berkeley Short-Channel IGFET Model) I-V model in BSIM3v3 is presented for circuit simulation. Including the major physical effects in state-of-the art MOS devices, the model describes current characteristics from subthreshold to strong inversion as well as from the linear to the saturation operating regions with a single I-V expression, and guarantees the continuities of Ids, conductances and their derivatives throughout all Vgs, Vds, and Tbs, bias conditions. Compared with the previous BSIM models, the improved model continuity enhances the convergence property of the circuit simulators. Furthermore, the model accuracy has also been enhanced by including the dependencies of geometry and bias of parasitic series resistances, narrow width, bulk charge, and DIBL effects. The new model has the extensive built-in dependencies of important dimensional and processing parameters (e.g., channel length, width, gate oxide thickness, junction depth, substrate doping concentration, etc.). It allows users to accurately describe the MOSFET characteristics over a wide range of channel lengths and widths for various technologies, and is attractive for statistical modeling. The model has been implemented in the circuit simulators such as Spectre, Hspice, SmartSpice, Spice3e2, and so on 相似文献
997.
998.
AlGaInP-sapphire glue bonded light-emitting diodes 总被引:1,自引:0,他引:1
Shoou-Jinn Chang Yan-Kuin Su Yang T. Chih-Sung Chang Tzer-Peng Chen Kuo-Hsin Huang 《Quantum Electronics, IEEE Journal of》2002,38(10):1390-1394
A novel method was proposed to glue an AlGaInP-GaAs light-emitting diode (LED) onto a transparent sapphire substrate. The absorbing GaAs was subsequently removed by selective wet etching. It was found that the emission efficiency could reach 401 m/W under 20-mA current injection for the 622-nm glue bonded (GB) AlGaInP-sapphire LED. It was also found that these GB LEDs are highly reliable, with small variations in operation voltage and luminescence intensity during the life test. 相似文献
999.
Fu-ren Lin Sheng-hsiu Huang Sheng-cheng Lin 《Engineering Management, IEEE Transactions on》2002,49(3):258-268
As businesses adopt electronic commerce, information exchange between business partners within a supply chain becomes more essential. Information exchange is often considered when companies implement the Extranet. This study aims to analyze the impact of various levels of information sharing including order, inventory, and demand information, which is based on transaction costs. This study further examines the effects on supply chain performance in electronic commerce. Specifically, the multiagent simulation system Swarm is employed to simulate and analyze the buyer-seller correlation in sharing information among business partners in supply chains. Our findings indicate that the more detailed information shared between firms, the lower the total cost, the higher the order fulfillment rate, and the shorter the order cycle time. In other words, information sharing may reduce the demand uncertainty that firms normally encounter. Firms that share information between trading partners tend to transact with a reduced number of suppliers. In sum, this work illustrates the effects of various levels of information sharing on supply chain performance in electronic commerce. 相似文献
1000.
Computation of full-vector modes for bending waveguide using cylindrical perfectly matched layers 总被引:4,自引:0,他引:4
Ning-Ning Feng Gui-Rong Zhou Chenglin Xu Wei-Ping Huang 《Lightwave Technology, Journal of》2002,20(11):1976-1980
A new full-vector approach to calculate leaky modes on three-dimensional bending waveguides is developed and demonstrated with the help of the cylindrical perfectly matched layer (CPML) numerical boundary conditions. By utilizing the complex coordinate stretching technique in the cylindrical system, a new set of full-vector wave equations for the bending waveguide structures are derived for the perfectly matched layer regions. Numerical solutions by the finite-difference schemes for the new wave equations are shown to yield highly accurate complex propagation constants (e.g., the bending-induced phase shifts and leakage losses) and modal field patterns, due primarily to the effective CPML. 相似文献