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991.
Peiyuan Lee Yongtao Gong Wanyi Gu 《Communications Letters, IEEE》2004,8(6):397-399
This letter studies routing and wavelength assignment (RWA) problem in wavelength-routed wavelength-division multiplexing networks with both uniform and nonuniform traffic model. Our research shows that the potential traffic load information is a crucial factor for routing algorithm design. Based on our analysis, an adaptive RWA algorithm is proposed. The simulation shows that the proposed algorithm performs much better than other adaptive RWA algorithms. 相似文献
992.
993.
Jianying Gong Tieyu Gao Xiuling Yuan Dong Huang 《Energy Conversion and Management》2008,49(6):1645-1651
The effects of air flow maldistribution on the performance of an air source heat pump chiller under frosting conditions were investigated experimentally. The results indicated that air flow maldistribution was the dominant factor leading to hunting of the thermostatic expansion valve for medium and/or large size finned tube evaporators. With air flow maldistribution degree (AMD) increasing, frost occurred earlier, and the frost layer grew faster. The operating characteristics became lower when AMD was increased. We found such phenomenon seemed to be related to both the difference of refrigerant outlet superheat and the frosting velocity. In the hunting stage, the frost block effect became the main factor degrading the refrigeration system performance. With AMD increasing, the heat pump system pertinent performance data (suction pressure, evaporation temperature, discharge pressure, refrigerant outlet temperature, etc.) were degraded more dramatically. 相似文献
994.
995.
996.
Gong Shengrong Guo Li Cui Zhiming 《电子科学学刊(英文版)》2007,24(6):815-820
Block matching has been used for motion estimation and motion compensation in the Audio and Video Standard (AVS) for years. While having an acceptable performance in describing motion between frames, it requires quite a few bits to represent the motion vectors. In certain circumstances, the use of global motion estimation and compensation would perform equally well or even better than the block matching in terms of motion accuracy, while it results in the coding of global motion model parameters. In this letter, we modify an AVS coder by adding (1) six global motion model parameters to the frame header, and (2) mode selection among INTRA, SKIP, INTER-16×16, INTER-16×8, INTER-8×16, INTER-8×8, and Global Motion Compensation (GMC) modes by Lagrange optimal rate-distortion criteria. Simulation results demonstrate that over 0.1dB improvement in PSNR is obtained compared to the AVS coder for an average coded P-frame with the same bitrate. 相似文献
997.
998.
低功耗、高性能多米诺电路电荷自补偿技术 总被引:1,自引:0,他引:1
提出了一种电荷自补偿技术来降低多米诺电路的功耗,并提高了电路的性能.采用电荷自补偿技术设计了具有不同下拉网络(PDN)和上拉网络(PUN)的多米诺电路,并分别基于65,45和32nm BSIM4 SPICE模型进行了HSPICE仿真.仿真结果表明,电荷自补偿技术在降低电路功耗的同时,提高了电路的性能.与常规多米诺电路技术相比,采用电路自补偿技术的电路的功耗延迟积(PDP)的改进率可达42.37%.此外,以45nm Zipper CMOS全加器为例重点介绍了功耗分布法,从而优化了自补偿路径,达到了功耗最小化的目的.最后,系统分析了补偿通路中晶体管宽长比,电路输入矢量等多方面因素对补偿通路的影响. 相似文献
999.
1000.
Hong‐Mei Gong Li Zhou Xiong‐Rui Su Si Xiao Shao‐Ding Liu Qu‐Quan Wang 《Advanced functional materials》2009,19(2):298-303
The chemical growth of silver nanorings that possess singly twinned crystals and a circular cross section via a reductive reaction solution is reported. The wire and ring diameters of the synthesized nanorings are in the ranges 80–200 nm and 4.5–18.0 μm, respectively. By lighting up the multipolar dark plasmons with slanted illumination, the silver nanoring exhibits unique focused scattering and large local‐field enhancement. We also demonstrate strong exciton–plasmon interactions between a monolayer of CdSe/ZnS semiconductor quantum dots and a single silver antenna‐like nanoring (nanoantenna) at the “hot spots” located at the cross points of the incident plane and nanoring; the position of these spots are tunable by adjusting the incidence angle of illumination. The tunable plasmonic behavior of the silver nanorings could find applications as optical nanoantennae or plasmonic nanocavities. 相似文献