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china Communications 2015年第7期12卷 96-107页

作者： HUANG Ying LEI Jing WEI Jibo institute of electronic Science and engineering National University of Defense Technology

In relay-assisted multi-user system, relay coding is important to enhance the robustness and reliability of cooperative transmission. For better adaptability and efficiency, two joint network and fountain coding(JNFC) schemes are proposed. When the condition of all direct channels is worse, JNFC scheme based on distributed LT(DLT) codes is used. Otherwise, JNFC scheme based on multi-dimensional LT(MD-LT) codes is suited. For both two above-mentioned schemes, the united degree distribution design method for short-length fountain codes is proposed. For the latter scheme, MD-LT codes are proposed for equal error protection(EEP) of each user. Simulation results and analysis show that the united degree distribution need less decoding overhead compared with other degree distribution for short-length fountain codes. And then, all users are protected equally in despite of asymmetric uplinks.

关键词： relay coding network coding fountain codes LT codes Raptor codes DLT MD-LT EEP

THE COUNTER-JET FORMATION IN AN AIR BUBBLE INDUCED BY THE IMPACT OF SHOCK WAVES

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Journal of Hydrodynamics 2011年第5期23卷 562-569页

作者： BAI Li-xin XU Wei-lin LI Chao GAO Yan-dong institute of Acoustics Chinese Academy of Sciences Beijing 100190 China State Key Laboratory of Hydraulics and Mountain River engineering Sichuan University Chengdu 610065China School of electronic and information engineering Liaoning Technical University Huludao 125105 China

The interaction of an air bubble （isolated in water or attached to a boundary） with shock waves induced by electric sparks is investigated by high-speed photography. The interaction is closely related to the counter-jet induced by the impact of shock waves. The formation of a counter-jet in an air bubble is related to the liquid jet formed in the same air bubble, but the mechanism is different with that of the counter-jet formation in a collapsing cavitation bubble. The formation of a counter-jet in an air bubble is related to discharge energy, air bubble size and radius of shock wave. With a given energy of the spark discharge, the formation of a counter-jet in an air bubble is related to δ / ε （the ratio of the dimensionless bubble-bubble distance to the dimensionless air bubble radius）. The counter-jet will only be produced when δ / ε is in the range of 1.2-2.2. The counter-jet in an air bubble is of an important nuclei-generating mechanism.

关键词： cavitation bubble shock wave counter-jet high-speed photography

Analysis and Simulation for Capacity of Time Division-Synchronous Code Division Multiple Access System

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Journal of Systems engineering and electronics 2002年第4期13卷 91-97页

作者： Sun Chengjun, Zhang Zhongzhao, Ba Yong2 & Cao Pengzhi (Communication Research ("enter, Harbin institute of technology, Harbin 150001, P. R. china Department of electronic engineering, Tsinghua university, Beijing 100084, P. R. china Research and Development Division, Shanghai Bell Company Limited, Shanghai 200092, P. R. china) Communication Research Center Harbin Institute of Technology Harbin 150001 P. R. China Department ot electronic engineering Isinghua University Beijing 100084 P. R. China Research and Development Division Shanghai Bell Company Lirmted Shanghai 200092 P. R. China

Capcity both in uplink and downlink of TD-SCDMA (time division-synchronous code division multiple access) system is studied in a multi-cell environment. The theoretical expressions of the mean of intercell interference in uplink and the mean of sum of power allocation in downlink are given, by which uplink and downlink capacity is analyzed. Furthermore, we give the simulation models for both uplink and downlink capacity. The results from theoretical analysis and simulation fit very well. In the end, the maximum number of users that TD-SCDMA system can serve for 12.2 k speech service is given.

关键词： Code division multiple access Probability Resource allocation Simulation Time division multiple access

One-Step interpolation Predictive Vector Quantization of LSP Parameters

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The Journal of china Universities of Posts and Telecommunications 1996年第1期3卷 21-26页

作者： Bao Changchun(Department of Telecommunication engineering, Changchun Posts and Telecommunications institute,Changchun 130012,P.R.china)Dai Yisong(Department of electronic engineering,Jinn university of technology,Changchun 130022,P.R.china) Department of Telecommunication engineering Changchun Posts and Telecommunications Institute Changchun 130012 P. R.China rinceton.edu

A new spectral coding approach,one-step interpolation predictive vectorquantimtion of the LineSPectrum Pair(LSP)coding,is proposed. With the use of the sufficient correlation of successive LSP vectorsand because of relatively slow variation of the short term spectrum of the speech waveform, the idea ofpredictive vector quantization and DPCM techniques are used to reduce variance Of the parameters to be quantics.18 bit/home split vector quantization scheme is designed to quantize the prediction *** average spectral distortion of 1.178 dB can be achieved when frame period is 30ms.

关键词： s:speech processing line spectrum Pair vector quantization

The Design, Performance Analysis and Implementation of VCAT in Backbone Networks for Software Radio System

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china Communications 2009年第1期6卷 85-91页

作者： Wang Peng1, JiaDong1, Jin Depeng2 , Zeng Lieguang2 1JiangNan institute of Computer technology, Wuxi, Jiangsu, 214083, P. R. china 2Department of electronic engineering, Tsinghua university, Beijing, 100084, P.R. china JiangNan institute of Computer technology Wuxi Jiangsu 214083 China Department of electronic engineering Tsinghua University Beijing 100084 China

Software Radio is a kind of promising technology in today and future’s communication systems. To share the resources of software radio systems to a large extent, we need to connect the instruments through backbone networks, such as the Multi-Service Transport Platform (MSTP), which is a dominating network technology that adopts both telecom and datacom traffic into existing transport infrastructures — Synchronous Digital Hierarchy (SDH). Virtual concatenation (VCAT) is one of the key technologies in MSTP. Compared with traditional contiguous concatenation, VCAT reduces transmission granularities, provides more flexibility to Network Management System (NMS) and as a result, improves the network efficiency greatly. In this paper, we introduce our design and implementation of VCAT module for a MSTP ASIC. The procedure of theoretical analysis to determine several important performance related parameters is also discussed in detail. The over- all design has been thoroughly simulated and verified through our self-made FPGA board, and has been successfully applied in our MSTP ASICs. We believe our work is significant for future development of software radio technology.

关键词： SRT VCAT NMS MSTP ASIC

Rapid Service Discovery based on Clustering

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Rapid Service Discovery based on Clustering

SR Torque Ripple Control Based on Power Spectrum Evaluation of Magnetic Flux Density of Air Gap

2010 3rd International Conference on Future BioMedical information engineering (FBIE 2010)

作者： Yanbin Peng School of information and electronic engineering Zhejiang university of science and technology hangzhou china

How to discover service from large scale service library precisely and rapidly is an interesting and important research *** efforts search service from the whole service library,ignoring the relationship between services,thus its searching speed is *** paper suggests cluster service library and search service in nearest sub service library,which has fewer *** results show that the new idea can improve service searching speed to a great extent.

关键词： service discovery clustering

来源： cnki会议评论

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SR Torque Ripple Control Based on Power Spectrum Evaluation ...

Improved FOCUSS method for reconstruction of cluster structured sparse signals in radar imaging

2005国际电机与系统学术会议

作者： Guangzhao Cui Xianghong Cao Hua Zhang Department of Cotrol Science and engineering Huazhong university of Science and technology Wuhan 430074 china College of Electrical and information engineering zhengzhou institute of Light Industry zhengzhou 450002 china Department of Electrical engineering Southeast university Nanjing 210096 china

＜正＞ This paper has introduced the SR motor torque ripple control scheme based on power spectrum evaluation of magnetic flux density in air gap. We analyze the feasibility of its realization theoretically and give s...

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Science china(information Sciences) 2012年第8期55卷 1776-1788页

作者： HU ChenXi1,2,LIU YiMin1,LI Gang1&WANG XiQin1 1I ntelligent Sensing Laboratory,Department of electronic engineering,Tsinghua university,Beijing 100084,china 2X i'an electronic engineering Research institute,Xi'an 710100,china Intelligent Sensing Laboratory Department of Electronic Engineering Tsinghua University Beijing China Xi’an electronic engineering Research institute Xi’an China

The high resolution imaging of distributed targets in millimeter-wave radar system is studied in this *** use Gaussian Mrakov random field(GMRF)to represent the clustering property of the *** novel method,called Clustering FOCUSS,incorporate an additional cluster constraint into the process of the focal underdetermined system solver(FOCUSS)*** results indicate that the novel algorithm has a higher imaging accuracy than the methods of Capon beamforming,the l1 norm algorithm and the FOCUSS algorithm.

关键词： antenna array high resolution imaging cluster sparsity GMRF Clustering FOCUSS

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基于密码技术的数字水印研究

计算机工程与应用 2003年第26期39卷 109-111页

作者：张涛汤光明孙怡峰中国人民解放军信息工程大学电子技术学院郑州450004

分析了Cox等人关于水印结构的理论,提出了利用密码技术构造水印序列的方法。利用该方法既实现了对版权信息的直观有效标识、又构造出了具有较强鲁棒性的水印。最后利用该方法实现了JPEG图像的数字水印。

关键词：数字水印序列密码鲁棒性不可见性