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Unequal error protection scheme for layered sources transmission over MIMO systems using spatial diversity and multiplexing technology

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The Journal of China Universities of Posts and Telecommunications 2015年第3期22卷 56-63页

作者： Zhang Yongjian Zhang Kexin Kang Yanmei yang dacheng School of Telecommunication Engineering Beijing University of Posts and Telecommunications University of International Relations Academic office Beijing University of Posts and Telecommunications

This paper proposes a hybrid scheme of the Alamouti coding and vertical bell labs layered space-time （V-BLAST） with the zero-forcing （ZF） receiver, which can achieve the unequal error protection （UEP） transmission in terms of the differences of importance in the layered sources. We analyze the tradeoff between spatial diversity and multiplexing in a mathematical manner, and prove the monotonic behavior of the crosspoint. Based on this scheme, we adopt V-BLAST to provide high data rates for the enhancement layer （EL） bitstreams, and adopt Alamouti coding to guarantee high reliability for the base layer （BL） bitstreams. Meanwhile, to improve the transmission reliability for the layered sources under the multiple-input multiple-output （MIMO） system with the limited-bandwidth and the total limited power, and to raise the frequency bandwidth efficiency, we take the power allocation considered in this proposed scheme. The simulation results show that the hybrid scheme has the average 1.9 dB and 1.3 dB gain in video peak signal-to-noise ratio （PSNR）, compared with the pure spatial diversity and pure spatial multiplexing scheme, respectively.

关键词： unequal error protection spatial diversity and multiplexing outage probability multiple-input multiple-output (MIMO) powerallocation

Superposition Effect of Passive Intermodulation for Cable Assemblies with Discrete Point-Sources

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China Communications 2015年第4期12卷 97-105页

作者： ZHAO Pei ZHANG Xupu yang dacheng HU Xiaoyan Wireless Theory & Technology Laboratory (WT&T) Beijing University of Posts & Telecommunication (BUPT) R&D center Jointcom Communication Technology Co. Ltd Division of Research China Mobile Group Design Institute Co.Ltd

In order to expand the cell coverage of wireless cellular systems, the number of passive components in wireless systems has been substantially increased. There can be many passive intermodulation(PIM) pointsources even in a device or a radio link, which may add up constructively or destructively. A modified point-source model with lossy components is proposed to evaluate the superposition effect of the forward and refl ected PIM in case of series connection. The index of the series connection factor(SCF) is employed for systems that incorporate multiple PIM sources to predict the important characteristics of the cumulative PIM, such as the maximum and minimum values and the limit form. Furthermore, some initial experimental results are given out and the deviation in the above-mentioned prediction is also analyzed.

关键词： nonlinearities passive inter-modulation(PIM) superposition effect seriesconnection

Increased complexity of gene structure and base composition in vertebrates

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Journal of Genetics and Genomics 2011年第7期38卷 297-305页

作者： Ying Wu Huizhong Yuan Shengjun Tan Jian-Qun Chen dacheng Tian Haiwang yang State Key Laboratory of Pharmaceutical Biotechnology Department of Biology Nanjing University Nanjing 210093 China

How the structure and base composition of genes changed with the evolution of vertebrates remains a puzzling question. Here we analyzed 895 orthologous protein-coding genes in six multicellular animals： human, chicken, zebrafish, sea squirt, fruit fly, and worm. Our analyses reveal that many gene regions, particularly intron and 3~ UTR, gradually expanded throughout the evolution of vertebrates from their invertebrate ancestors, and that the number of exons per gene increased. Studies based on all protein-coding genes in each genome provide consistent results. We also find that GC-content increased in many gene regions （especially 5＇ UTR） in the evolution of endotherms, except in coding-exons. Analysis of individual genomes shows that 3t UTR demonstrated stronger length and GC-content correlation with intron than 5~ UTR, and gene with large intron in all six species demonstrated relatively similar GC-content. Our data indicates a great increase in complexity in vertebrate genes and we propose that the requirement for morphological and functional changes is probably the driving force behind the evolution of structure and base composition complexity in multicellular animal genes.

关键词： GC-content Gene structure Intron UTR Vertebrate Endotherm

Electrodeposition of Ni-W Amorphous Alloy and Ni-W-SiC Composite Deposits

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Journal of Materials Science & Technology 2000年第3期16卷 323-326页

作者： Zhongcheng GUO, Xiaoyun ZHU, dacheng ZHAI and Xianwan yang (Department of Metallurgy, Kunming University of Science and Technology, Kunming 650093, China) Department of Metallurgy Kunming University of Science and Technology Kunming 650093 China

Ni-W alloys and their composite deposits are electroplated on the metals when an appropriate complex agent is selected on the base of the theories of electrochemistry and complex chemistry, and the principle of induced codeposition. Effects of the bath composition, pH value, temperature and current density on the electrode position of Ni-W alloys and their composite deposits have been investigated, and the effect of heat treatment temperature on the hardness, structure and cohesive force of the amorphous Ni-W alloys and their composite deposits are also discussed. Results showed that the alloys containing more than 44 wt pct W content and the composite deposits containing 7.8 wt pct SiC content could be obtained by making use of the appropriate bath composition and plating conditions. Alloys and their composite deposits with over 44 wt pct W content show amorphous structure. The hardness of amorphous Ni-W alloys and their composite deposits increases obviously when heated, and can reach to 1350 HV and 1520 HV respectively for 46 wt pct W content. The cohesion on Cu, carbon steel and stainless steel is very good.

关键词： SiC Electrodeposition of Ni-W Amorphous Alloy and Ni-W-SiC Composite Deposits Ni

Synthesis of novel β-amino ketones containing a p-aminobenzoic acid moiety and evaluation of their antidiabetic activities

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Science China Chemistry 2013年第4期56卷 490-504页

作者： TANG GuangXia YAN JuFang FAN Li XU Jin SONG XiaoLi JIANG Li LUO LingFei yang dacheng School of Chemistry and Chemical Engineering Southwest University Drug Screening Center Chengdu Di Ao Pharmaceutical Group Co. Ltd. Schlumberger Technology Corporation School of Life Science Southwest University

The synthesis of two series of [3-amino ketones containing a p-aminobenzoic acid moiety （TM.1 and TM-2） using a modified protocol of the Mannich reaction is reported. The molecular structures of a total of tweenty three new target compounds were characterized by ~H NMR, 1~C NMR, ESI-MS and HR-MS. Subsequently, their antidiabetic activities were screened in vitro. The c^-glucodase inhibition （c^-GI） activity of compound le reached a remarkable level of 66.50%. The peroxisome proliferator- activated receptor （PPAR） relative activation activities of six compounds are above 80%, and in particular 2i displays an un- precedentedly high PPAR of 130.91%. The structure-activity relationships of the compounds were established. 2i is also sub- ject to further in-depth investigation.

关键词： diabetes mellitus ot-glucosidase peroxisome proliferator-activated receptor β-amino ketone Mannich reaction

Dynamic System Level Frequency Spectrum Allocation Scheme Based on Cognitive Radio Technology

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China Communications 2014年第7期11卷 84-91页

作者： WEI Zaixue yang dacheng SANG Lin Wireless Theories and Technologies Lab (WT&T) Beijing University of Posts and TelecommunicationsBeijing 100876 Beijing P. R. China

Cognitive radio is being widely discussed,and resource allocation scheme is drawing a lot of *** the existed resource allocation strategies have successfully enhanced spectrum efficiency,some critical challenges still remain unanswered such as the jointly consideration of the efficiency and fairness,the rational description of the spectrum resources,and the execution mode of the spectrum *** paper presents a system level dynamic frequency spectrum allocation scheme based on a central heterogeneous network architecture,evaluates the matching degree of the spectrum demand and the available spectrum resources with corresponding matrices,jointly considers the efficiency and fairness of different cognitive radio *** results and the application scenario are also presented and analyzed.

关键词： frequency spectrum allocationscheme heterogeneous network cognitiveradio spectrum resource manage center

Asymptotic performance of amplify-and-forward MIMO relaying with transmit antenna selection

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Science China(Information Sciences) 2010年第12期53卷 2631-2641页

作者： CAO Lei ,yang dacheng,yang HongWen,FENG Chao & ZHANG Xin School of Information and Communication,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information and Communication Beijing University of Posts and Telecommunications Beijing China

This paper proposes two schemes,TAS-SD&RD and TAS-SR&RD,in which transmit antenna selection(TAS) strategies are combined with amplify-and-forward(AF) protocol in MIMO relaying scenario considering the destination has only limited channel state information(CSI) of the source-to-relay channel,and analyzes asymptotic performance of the two *** source,destination,and relay are equipped with multiple antennas,denoted by N S,N D,and N R,***,the paper derives the asymptotic outage probability and symbol error rate(SER) of the proposed schemes in the cooperative AF MIMO relaying *** analyses in high SNR regime lead to the conclusion that TAS-SD&RD and TAS-SR&RD can achieve full diversity order,N S N D + N R min{N S,N D },in some antenna configurations of the cooperative *** results that confirm our analyses are also presented in the paper.

关键词： cooperative amplify-and-forward(AF) multiple-input multiple-output(MIMO) relaying transmit antenna selection(TAS)

A CONFIGURATION FOR REALIZATION OF THE MULTICHANNEL AND HIGH-ORDER IIR ADAPTIVE FILTERS

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Journal of Electronics(China) 1990年第1期7卷 45-53页

作者：杨大成王德隽 Beijing University of Posts and Telecommunications Beijing

This paper develops a new hyperstable adaptive algorithm which can be used inthe multichannel ⅡR conflguration and/or the high-order ⅡR or zero-pole configuration for jointprocess estimation.

关键词： Filter IIR filter Adaptive filter

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含RGD序列环肽以及类似物的合成方法研究

有机化学 2002年第4期22卷 239-247页

作者：杨宇杨大成肖晴钟裕国四川大学华西药学院成都610041

通过文献检索 ,总结了含RGD序列环肽以及类似物的合成方法 .该类化合物的合成方法较多 ,生物活性较好。

关键词： RGD序列类似物环肽合成 DMP728 Cyclo 含硫环肽