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Science china(Information Sciences) 2010年第6期53卷 1242-1250页

作者： JIANG YongQuan 1 , SHEN MinFen 1 & ZHOU YuanPing 2 1 department of electronic engineering, Shantou University, Shantou 515063, china.2.department of electronic engineering, Sichuan University, Chengdu 610064, china 1. department of electronic engineering Shantou University Shantou 515063 China2. Department of Electronic Engineering Sichuan University Chengdu 610064 China

Departing from the narrowband channel model, more and more researchers have recently considered the application of multiple-input multiple-output(MIMO) systems over frequency-selective fading channels in combination with the orthogonal frequency-division multiplexing(OFDM) *** this paper, we focus on the capacity of MIMO-OFDM systems and how to increase the *** has been proved that the capacity of a MIMO system with space-dimensional water-filling power allocation is greater than that of the system with uniform power *** MIMO-OFDM systems, there is an additional degree of freedom to allocate power with respect to MIMO systems:the OFDM sub-channels in *** the singular value decomposition(SVD) applied to the channel frequency response matrix, the two-dimensional water-filling power allocation algorithm for MIMO-OFDM systems is proposed based on the Lagrange method, and the corresponding capacity analysis formula is *** results show that the capacity of a MIMO-OFDM system with the proposed two-dimensional water-filling power allocation is greater than that of the system with uniform power allocation and also greater than that of the system with the one-dimensional water-filling power allocation.

关键词： MIMO-OFDM two-dimensional water-filling power allocation capacity analysis singular value decomposition(SVD)

Self-Organizing Tunnel Peers

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计算机工程 2002年第S1期28卷 7-12页

作者： CHEN Maoke , LI Xing (department of electronic engineering, Tsinghua University, Beijing 100084,china ) department of electronic engineering Tsinghua University Beijing 100084China

Tunneling is an important approach in IPv6 transition techniques. The tunnel broker model provides a way to build virtual IPv6 networks without manual ***, neither it adapts performance variation on the IPv4 infrastructure, norit is a scalable solution for a wide-area IPv6 networking environment. In this paper, a self-organizing tunnel peer (SOTP) model is *** peers are clustered in the SOTP system so that optimization is scalable. Four primitive operations related to --cluster constructionarrest,release,division and deathendow the system with the nature of self-organization. Occurrence and behavior of the operations are decided by criteria on the IPv4 end-to-end performance; hence measurement is an indispensable component of the system. The metabolism of cluster relaxes the requirement to accuracy of measurement and optimization.

关键词： S elf-organizationTunnelingEnd-to-end measurementIPv6

A fast stereoscopic video coding algorithm based on JMVM

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Science china(Information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2 , JIA KeBin 1 , CHAN YuiLam 2 , FU ChangHong 2 & SIU WanChi 2 1 department of electronic Information & Control engineering, Beijing University of Technology, Beijing 100124, china.2.department of electronic Information engineering, Hong Kong Polytechnic University, Hong Kong, china 1. department of electronic Information & Control engineering Beijing University of Technology Beijing 100124 China2. Department of Electronic Information Engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.264 stereoscopic video coding disparity estimation motion estimation

Migration Effect of Temperature on Formaldehyde in Porous Building Materials

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湖南大学学报（自然科学版） 2009年第S1期36卷 1-4页

作者： SHEN Xiao-zhong1,2,CHEN Zhen-qian1(1.School of Energy and Environment,Southeast University,Nanjing,Jiangsu 210096,china.2.department of electronic engineering,Wuxi Institute of Commerce,Wuxi,Jiangsu 214153,china) School of Energy and Environment Southeast University Nanjing 210096 China department of electronic engineering Wuxi Institute of Commerce Wuxi 214153 China

A coupled heat and formaldehyde migration model based on the non-equilibrium thermodynamic theory and molecule movement theory was *** effect of temperature on the transport coefficients was simulated,and the simulation results were validated with experimental data from the *** calculation shows that air exchange rate larger than 2 h-1 should be prevented,if the purpose is only for formaldehyde emissions *** effects of temperature on formaldehyde migration are obvious.

关键词： formaldehyde migration temperature gradient porous building materials

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On the TOPS mode spaceborne SAR

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Science china(Information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2 , HONG Wen 3 & MAO ShiYi 2 1 department of electronic engineering, Beijing Institute of Technology, Beijing 100081, china.2.department of electronic engineering, Beihang University , Beijing 100191, china 3 Institute of electronics,Chinese Academy of Sciences, Beijing 100190, china 1. department of electronic engineering Beijing Institute of Technology Beijing 100081 China2. Department of Electronic Engineering Beihang University Beijing 100191 China3. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS

Research on dual-stator winding multi-phase high-speed induction generator with rectifier load

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Science china(Technological Sciences) 2008年第6期51卷 683-692页

作者： WANG XiangHeng1 & WU XinZhen2 1 department of Electrical engineering, Tsinghua University, Beijing 100084, china.2.department of Electrical engineering, Qingdao University, Qingdao 266071, china 1. department of Electrical engineering Tsinghua University Beijing 100084 China 2. department of Electrical engineering Qingdao University Qingdao 266071 China

Based on analysis and calculation of the relation between current harmonics and MMF harmonics in the dual-stator winding multi-phase high-speed induction gen-erator with a rectifier load, a new idea, which divides the generator system into two sub-systems to be analyzed individually, is presented. For the sub-system of the 12-phase power winding with a rectifier load, the loop current method is used to establish network equation set in terms of the network graph theory. The numerical stability problem is solved by alternating use of fixed time-step and varied time-step, and the voltage and current with their fundamental components of the power winding are obtained. For the other sub-system of the induction generator with dual-stator winding and solid cage rotor, the electromagnetic field analysis method and the multi-variable optimization approach are combined to get the con-trol winding current and stator frequency. Calculated results well match experiment results, indicating that the new proposed method is of effectiveness and high ac-curacy.

关键词： dual-stator winding induction generator rectifier load MMF analysis loop current method finite element method optimization approach

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An optimal adaptive filtering algorithm with a polynomial prediction model

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Science china(Information Sciences) 2011年第1期54卷 153-162页

作者： TAN JiaJia & ZHANG JianQiu department of electronic engineering,Fudan University,Shanghai 200433,china 1. department of electronic engineering Fudan University Shanghai 200433 China

A new approach to the optimal adaptive filtering is proposed in this *** this approach,a polynomial prediction model is used to describe the time-variant/invariant impulse response coeffcients of an identified *** the polynomial prediction model is viewed as the state equations of the identified impulse response coeffcients and the relationships between the inputs and outputs of the system are regarded as the measurements of the states,our adaptive filtering can be achieved in the framework of the Kalman filter. It is understood that Kalman filter is optimal in the sense of the MAP(maximum a posteriori),ML(most likelihood)and MMSE(minimum mean square error)under the linear and Gaussian white noise *** a result,our algorithm is also optimal in the statistical senses as Kalman filter does,provided that the impulse response coeffcients can be modeled by a *** only do the analytical results of the algorithm but also the simulation results show that our algorithm outperforms the traditional known algorithms.

关键词： adaptive filters polynomial prediction model impulse response coeffcients process equation Kalman filter optimal

Compact High-performance Bulk Optical Isolator

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Chinese Journal of Lasers 1998年第2期B7卷 31-36页

作者： WANG Lindou(department of electronic engineering,Tianjin University,Tianjin 300072,china) Tianjin Univ Tianjin China

ＣｏｍｐａｃｔＨｉｇｈ┐ｐｅｒｆｏｒｍａｎｃｅＢｕｌｋＯｐｔｉｃａｌＩｓｏｌａｔｏｒＷＡＮＧＬｉｎｄｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａ... 详细信息

ＣｏｍｐａｃｔＨｉｇｈ┐ｐｅｒｆｏｒｍａｎｃｅＢｕｌｋＯｐｔｉｃａｌＩｓｏｌａｔｏｒＷＡＮＧＬｉｎｄｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＥｌｅｃｔｒｏｎｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｉａｎｊｉｎＵｎｉｖｅｒｓｉｔｙ，Ｔｉａｎｊｉｎ３０００７２，Ｃｈｉｎａ）...

关键词： isolaton fiber optic communication bulk isolator

Reconfigurable design and implementation of the MD6 Hash function

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 109-115页

作者： GAO Xian-wei department of electronic and Information engineering,Beijing electronic Science and Technology Institute,Beijing 100070,china [a] department of electronic Information engineering Beijing Electronic Science Technology Institute Beijing 100070 China

Efficient reconfigurable field programmable gate array （FPGA） architectures for the MD6-224/256/384/512 Hash algorithm are proposed in this article. The basic iterative compact design requires 923 ALMs and achieves a throughput ranging from 225 Mbit/s to 394 Mbit/s at a maximum frequency of 198 MHz. The 32-step-urtrolled high-throughput design requires 7 090 ALMs and achieves a throughput ranges from 5 776 Mbit/s to 9 490 Mbit/s at a maximum frequency of 173 MHz. The simulation results show that high flexibility and efficient FPGA implementation of the MD6 Hash function is achieved.

关键词： SHA-3 MD6 reconfigurable iterative loop-unrolling

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