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空分多址系统的码本设计

上海交通大学学报 2009年第3期43卷 385-388页

作者：陈磊罗汉文佘锋刘仁茂上海交通大学电子信息与电气工程学院上海200240 夏普电子上海有限公司高科技研发中心上海201203

提出了一种新的空分多址多天线系统码本设计算法.该算法改进了通用型Lloyd算法,并基于改进型Lloyd算法生成了由一系列正交码本子集组成的空分多址系统的码本.仿真结果表明,本文的码本设计算法降低了信道状态信息的矢量量化误差,同时,基... 详细信息

提出了一种新的空分多址多天线系统码本设计算法.该算法改进了通用型Lloyd算法,并基于改进型Lloyd算法生成了由一系列正交码本子集组成的空分多址系统的码本.仿真结果表明,本文的码本设计算法降低了信道状态信息的矢量量化误差,同时,基于本算法生成的码本,可以提高带有限反馈的空分多址系统的多用户速率和.

关键词：多天线空分多址 Lloyd算法有限反馈矢量量化

维普期刊数据库

Preparative isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high-speed counter-current chromatography

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Journal of Pharmaceutical Analysis 2012年第4期2卷 258-263页

作者： Mei Yang a,b , Xin-Jun Xu a,b,Chun-Yan Xie a,b , Jie-Yun Huang a,b , Zhi-Sheng Xie a,b , De-Po Yang a,b a School of Pharmaceutical Sciences, Sun Yat-Sen university, Guangzhou 510006, China b Guangdong Technology research center for advanced Chinese Medicine, Guangzhou 510006, China School of Pharmaceutical Sciences Sun Yat-Sen University Guangzhou 510006 China. Guangdong Technology research center for advanced Chinese Medicine Guangzhou 510006 China.

An efficient method for the isolation and purification of 12,13-dihydroxyeuparin from Radix Eupatorii Chinensis by high speed counter-current chromatography (HSCCC) was established in this paper. The ether extracts of Radix Eupatorii Chinensis were purified by HSCCC with a solvent system of hexyl hydride-ethyl acetate-methanol-water (1:2:1:2, v/v/v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase. About 8.4 mg of 12, 13-dihydroxyeuparin was obtained from 200 mg of ether extracts from Radix Eupatorii Chinensis in one-step HSCCC separation, with the purity of 96.71%, as determined by HPLC. After methanol- water recrystallization, the purity of 12,13-dihydroxyeuparin reached 99.83%. Such a simple and effective method was fairly useful to prepare pure compound as reference substances for related study on Radix Eupatorii Chinensis.

关键词： Radix Eupatorii Chinensis High speed counter- current chromatography (HSCCC) 12,13-dihydroxyeuparin

维普期刊数据库

Approaches to Delay-Dependent Robust H∞ Control of Uncertain Discrete-Time T-S Fuzzy Systems with Interval Time-Varying Delay

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Approaches to Delay-Dependent Robust H∞ Control of Uncertai...

第二十七届中国控制会议

作者： Qiu Jianbin1,Feng Gang2,Yang Jie3,Fan Yuan1 1.Department of manufacturing Engineering and Engineering Management,university of Science and Technology of China(USTC) & City university of Hong Kong(CityU) Joint advanced research center,Suzhou 215123,P.R.China 2.Department of manufacturing Engineering and Engineering Management,City university of Hong Kong,Kowloon,Hong Kong 3.Department of Precision Machinery and Instrumentation,university of Science and Technology of China,Hefei 230026,P.R.China

This paper investigates the problem of delay-dependent robust H∞ state-feedback control for a class of uncertain discrete-time state-delayed T-S fuzzy *** on a novel delay and fuzzy-basis-dependent Lyapunov-Krasovskii functional incorporating a free-weighting matrix approach,some new delay-dependent sufficient conditions for robust H∞ controller synthesis are derived in terms of linear matrix inequalities（LMIs） .Numerical examples are also provided to illustrate the effectiveness of the proposed approaches.

关键词： Discrete-time T-S fuzzy systems Time-delay systems Delay-dependent Robust control Linear-fractional uncertainties Linear matrix inequalities

The precipitation strengthening behavior of Cu-rich phase in Nb contained advanced Fe-Cr-Ni type austenitic heat resistant steel for USC power plant application

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Progress in Natural Science:Materials International 2012年第3期22卷 175-185页

作者： Cheng-yu Chi a, Hong-yao Yu b, Jian-xin Dong b, Wen-qing Liu c, Shi-chang Cheng d, Zheng-dong Liu d, Xi-shan Xie b a School of Metallurgical and Ecological Engineering, university of Science & Technology Beijing, Beijing 100083, China b School of Materials Science and Engineering, university of Science & Technology Beijing, Beijing 100083, China c Instrumental Analysis & research center, Shanghai university, Shanghai 200444, China d Central Iron and Steel research Institute, Beijing 100081, China [a] School of Metallurgical and Ecological Engineering University of Science & Technology Beijing Beijing 100083 China [b] School of Materials Science and Engineering University of Science & Technology Beijing Beijing 100083 China [c] Instrumental Analysis & research center Shanghai University Shanghai 200444 China [d] Central Iron and Steel research Institute Beijing 100081 China

Copper has been used as a strengthening element in newly developed Fe-Cr-Ni type austenitic heat resistant steel for inducing Cu-rich phase precipitation to meet high temperature strength requirement for 600 ℃ Ultra Super-Critical (USC) coal fired power plants for many years. However, the precipitation behavior and strengthening mechanism of Cu-rich phase in these advanced austenitic heat resistant steels is still unclear. In order to understand the precipitation strengthening behavior of Cu-rich phase and to promote high strength austenitic heat resistant steel development, 18 Cr9 NiCuNb steel which is a Cu-added Nb contained advanced Fe-Cr-Ni type austenitic heat resistant steel has been selected for this study to be aged at 650 ℃ till to 10,000 h. Micro-hardness and room temperature tensile test were conducted after long-time aging. SEM, TEM, HRTEM and three dimensional atom probe (3DAP) technology accompanying with thermodynamic calculation have been used to investigate the Cu-rich phase precipitation behavior during 650 ℃ aging. The experimental results showed that Cu atoms can quickly concentrate in clusters at very early precipitation stage to form the fine nano-size Cu-rich "segregation areas" within less than 1 h at 650 ℃. With increasing aging time at 650 ℃ Cu atoms continuously concentrate to Cu-rich segregation areas (clusters) and simultaneously other kinds of atoms such as Fe, Cr and Ni diffuse away from Cu-rich segregation areas to austenitic matrix, and finally to complete the transformation from Cu-rich segregation areas to Cu-rich phase. However, there is only Cu atoms concentration but not crystallographic transformation from early stage of Cu-rich clusters forming to the final Cu-rich phase formation. Even the Cu atom becomes the main composed element after 500 h aging at 650 ℃ the Cu-rich phase still keeps coherent relationship with austenitic matrix. According the experimental results in this study, Cu-rich phase precipitation sequence which st

关键词： USC power plant Austenitic heat resistant steel Microstructure Cu-rich phase TEM 3DAP

Bounds of performance of normalized throughput in WDM+OCDMA system

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Bounds of performance of normalized throughput in WDM+OCDMA ...

Asia-pacific Optical Communications 2004

作者： Ji Jianhua Xu Ming Ma Junxian Wang Ke Yang Fang Yang Shuwen advanced Technology research center of Shenzhen university Shenzhen P.R.China 518060

The performance of normalized throughput in WDM+OCDMA system is studied. When all simultaneous users are equally allocated to different wavelength channels, upper bound of normalized throughput is obt

关键词： optical code-division multiple-access(OCDMA) wavelength division multiplxing(WDM) bit error rate throughput

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基于区分服务的IP QoS实现技术

计算机工程与应用 2001年第18期37卷 47-49页

作者：蔡茂国杨淑雯深圳大学新技术研究中心深圳518060

文章讨论了基于区分服务（DiffServ）的IP网络中，路由器转发IP分组的三种模式（EF、AF、DE），讨论了边缘路由器对IP分组进行分类、测量、标记、整形和丢包的处理方法，分析了区分服务与服务水平协议（SLA）结合的重要性，给出了支持... 详细信息

文章讨论了基于区分服务（DiffServ）的IP网络中，路由器转发IP分组的三种模式（EF、AF、DE），讨论了边缘路由器对IP分组进行分类、测量、标记、整形和丢包的处理方法，分析了区分服务与服务水平协议（SLA）结合的重要性，给出了支持端到端实时业务传输QoS的基于区分服务的IP网络结构。

关键词：互联网区分服务服务质量网络通信路由器

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An Artificial Compound Eyes Imaging System Made by MEMS Technology

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An Artificial Compound Eyes Imaging System Made by MEMS Tech...

第11届粤港机械电子工程技术与应用研讨会

作者： DI Si~(1,2),LIN Hui~1,DU Ruxu~(1,2) 1.Precision Engineering research center,Shenzhen Institute cf advanced Technology, Shenzhen,China 2.Institute of Precision Engineering,the Chinese university of Hong Kong, Hong Kong SAR,China

This paper introduces an artificial compound eyes imaging *** planar structure can be easily using MEMS fabrication ***,we used the photo-resist reflow method to fabricate a 9×9microlens array on a planar glass substrate,as the lenses of the compound *** transverse size is 0.9×0.9 cm and thickness is about 0.7 *** we built an imaging system where object images are captured by the micro- lens array using a CMOS *** an example,the imaging system is used to view a character "A".It is found that each microlens can image the character "A" *** a result,a 9×9 multiple-image is ***,the object image is reconstructed from the multiple-image by digital process *** experimental results indicate that our system can effectively imitate the imaging mechanism of the compound *** system has a number of advantages such as simple and compact in size.

关键词： Compound eyes computer vision MEMS