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951.
城市信息化离不开城市信息高速公路 ,宽带城域网的建设为城市信息化提供了高速通道。IP网和ATM网将是宽带城域网的核心平台 ,宽带接入技术将成为城域网接入的主要手段 ,宽带城域网整体解决方案离不开IP软技术的应用 ,三网融合将是宽带城域网发展方向。增值业务是网络不断发展的动力所在 相似文献
952.
953.
954.
ZrO2/SiO2双层膜膜间渗透行为初步研究 总被引:4,自引:0,他引:4
用溶胶-凝胶技术,采用提拉镀膜法在K9玻璃基片上镀制了ZrO2/SiO2双层膜和SiO2/ZrO2双层膜,研究了这两种膜层之间的渗透问题。用X射线光电子能谱仪(XPS)测量了薄膜的成分随深度方向的变化,用反射式椭偏仪对X射线光电子能谱仪测得的实验结果进行模拟与验证。结果表明,用X射线光电子能谱仪测得的实验结果建立的椭偏模型,模拟出来的椭偏曲线和用椭偏仪测量出来的椭偏曲线十分吻合;对于ZrO2/SiO2双层薄膜,膜层间的渗透情况不是很严重,在薄膜界面处薄膜的成分比变化非常明显,到达一定深度后薄膜的成分不再随深度的变化而变化;SiO2/ZrO2双层膜膜层界面间的渗透十分严重,渗透层的深度比较大,底层几乎发生了完全渗透。 相似文献
955.
考虑到温度和工艺参数浮动的影响,对休眠双阈值footed多米诺电路的漏电流特性进行了系统的量化研究和比较,得到了不同温度下的最佳休眠状态.基于65和45nm BSIM4模型的HSPICE仿真表明:与业已提出的CHIL(时钟为高,输入均为低电平)状态和CHIH(时钟和输入均为高电平)状态相比,本文提出的CLIL(时钟和输入均为低电平)状态更有利于减小低温下电路的漏电流和高温下的多扇入电路的漏电流.而且,分析了工艺参数的浮动对双阈值footed多米诺电路的漏电流特性的影响,并给出了温度和工艺参数浮动下,双阈值footed多米诺电路漏电流最小的休眠状态. 相似文献
956.
957.
In this paper, we propose a new combinative scheme to combine with parity check and block coding methods for the reduction
of the peak to average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) system. In the proposed schemes,
the simulation results shown that Peak-to-Average Power Ratio (PAPR) can be reduced by 3.502 dB. The results of this mapped
can be shown that PAPR is reduced. The principle of the scheme is illustrated with the specific example of an eight-carriers
signal and its computer simulation results. All simulation results have compare with ideal channel case and AWGN case separately;
both of cases are shown the PAPR reduced indeed.
Do Horng Guo received his B.S. Degree in Electronic Engineering from National Taiwan Marine Science University, Keelung, Taiwan, in 1983,
and M.S. Degree in Computer Communication from Northrop University, Los Angeles, USA, in 1986. He is enrolled in Ph.D program
in Graduate Institute of Communication Engineering of Tatung University from 2001. His current interest includes wireless
communication system and digital signal processing.
Chau-Yun Hsu received his B.S. degree M.S. and Ph.D in Electrical Engineering from Tatung Institute of Technology, Taipei, Taiwan, in
1981, 1983 and 1988, respectively.
He was the lecturer in Department of Electrical Engineering of Tatung University from 1983 to 1985. From 1988 to 1997, he
served as the Associate professor of Tatung University. Since 1998, he has been the Chair Professor of Graduate Institute
of Communication Engineering of Tatung University. Now he is also the chair of department of Electrical Engineering of Tatung
University. His current interest includes Wireless Channel Model and Estimation, Machine Learning, Digital Signal Processing
and Image Processing. 相似文献
958.
959.
Weiping Wu Hongliang Zhang Ying Wang Shanghui Ye Yunlong Guo Chongan Di Gui Yu Daoben Zhu Yunqi Liu 《Advanced functional materials》2008,18(17):2593-2601
High‐performance organic transistor memory elements with donor‐polymer blends as buffer layers are presented. These organic memory transistors have steep flanks of hysteresis with an ON/OFF memory ratio of up to 2 × 104, and a retention time in excess of 24 h. Inexpensive materials such as poly(methyl methacrylate), ferrocene and copper phthalocyanine are used for the device fabrication, providing a convenient approach of producing organic memory transistors at low cost and high efficiency. 相似文献
960.
Pu Guo Zubin Wang Liping Heng Yuqi Zhang Xuan Wang Lei Jiang 《Advanced functional materials》2019,29(11)
Smart manipulation of liquid/bubble transport has garnered widespread attention due to its potential applications in many fields. Designing a responsive surface has emerged as an effective strategy for achieving controllable transport of liquids/bubbles. However, it is still challenging to fabricate stable amphibious responsive surfaces that can be used for the smart manipulation of liquid in air and bubbles underwater. Here, amphibious slippery surfaces are fabricated using magnetically responsive soft poly(dimethylsiloxane) doped with iron powder and silicone oil. The slippery gel surface retains its magnetic responsiveness and demonstrates strong affinity for bubbles underwater but shows small and switching resistance forces with the water droplets in air and bubbles underwater, which is the key factor for achieving the controllable transport of liquids/bubbles. On the slippery gel surface, the sliding behaviors of water droplets and bubbles can be reversibly controlled by alternately applying/removing an external magnetic field. Notably, compared with slippery liquid‐infused porous surfaces, the slippery gel surface demonstrates outstanding stability, whether in air or underwater, even after 100 cycles of alternately applying/removing the magnetic field. This surface shows potential applications in gas/liquid microreactors, gas–liquid mixed fluid transportation, bubble/droplet manipulation, etc. 相似文献