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Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china.information Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2 & FENG GuangZeng3 1department of electronic and information Engineering, zhejiang Institute of media and communications, hangzhou 310018, china.2department of information Engineering, Jiangsu City Vocation College, Nanjing 210036, china.3College of Communication and information Engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, china 1. department of electronic and information Engineering Zhejiang Institute of Media and Communications Hangzhou 310018 China2. Department of Information Engineering Jiangsu City Vocation College Nanjing 210036 China3. College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding

Effect of surface passivation on optical and electronic properties of ultrathin silicon nanosheets

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Science china.information Sciences) 2012年第6期55卷 1469-1474页

作者： WANG Le 1,2,WU Ke 2,DONG QianMin 1,LI XiaoYan 1,XIONG SiYu 1,XU LeiTing 3 & LIANG Pei 1 1 College Of electronic Science and Engineering,china.Jiliang university,hangzhou 310018,china.2 department of engineering,zhejiang university,hangzhou 310000,china.3 Hang Zhou Urban Infrastructure Construction and Development Center,hangzhou 310000,china 1. College Of electronic Science and Engineering China Jiliang University Hangzhou 310018 China2. Department of engineering Zhejiang University Hangzhou 310000 China3. Hang Zhou Urban Infrastructure Construction and Development Center Hangzhou 310000 China

The binding energy,electronic structure and optical properties of H-,H 3 C-,and HS-cluster-passivated ultrathin silicon (single-layer and double-layer) nanosheets were calculated using density functional theory based on the plane-wave ultra-soft ***,the most stable configuration was selected from passivated configurations according to the principle of lowest energy after calculating their total *** the density of state and the band structure of the different passivated systems were *** was found that different passivation clusters could affect the forbidden band,theremore the passivated cluster with sulfur could greatly decrease the width of the forbidden band through electron ***,the light absorption and reflection properties were also *** results were conducive to the development of silicon-based optoelectronic devices.

关键词： density functional theory surface passivation super-thin silicon nanosheets electronic structure

A study of the crystallization kinetics of Ge-Te amorphous systems

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International Journal of Minerals,Metallurgy and Materials 2007年第S1期15卷 64-67页

作者： Feng Yan1), Tiejun Zhu1), Xinbing Zhao1), and Shurong Dong2) 1) State Key Laboratory of Silicon Materials, department of Materials Science and Engineering, zhejiang university, hangzhou 310027, china.2) department of information and electronics Engineering, zhejiang university, hangzhou 310027, china

The glass-forming ability of binary GexTe100-x (x=15, 20, 30) alloys was investigated. The crystallization mechanism of these amorphous bulks was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calo- rimetry (DSC). The temperature of glass transition, the temperature of crystallization, the activation energy for glass transition and crystallization, and the order of the crystallization mechanism were calculated from the different heating-rates.

关键词： Ge-Te glass glass transformation activation energy crystallization mechanism

DESIGN AND RESEARCH OF QUASI-PLANAR SELF-ALIGNED SILICON AVALANCHE electron EMISSION ARRAY

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Journal of electronics(china. 1999年第1期16卷 88-92页

作者： Zhu Dazhong( Institute of Power Devices, department of information and electronic Engineering, zhejiang university, hangzhou 310027)

The device structure and technical processings of quasi-planar self-aligned silicon avalanche electron emission array arc introduced. The processing step at the edge of electron emission region is about 10nm only and the width of self-aligned current channel of shallow As implantation is about 3μm. Its I-V characteristics show a larger linear region and lower series resistance than that of the previous silicon avalanche electron emission devices. Some of the electron emission characteristics are also discussed in this paper.

关键词： Vacuum microelectronics electron emission Cold cathode

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无线信道视频流编码与自适应传输方案

计算机工程与应用 2004年第20期40卷 158-160页

作者：乔耿嘉王洪玉浙江大学信息与电子工程学系杭州310027

由于无线信道的时变特性和移动设备有限的能量资源,保证无线网络视频流传输的Qos是一项比较困难的任务。文章提出了一种基于无线网络的视频流自适应传输架构。这个架构不仅动态的估计了无线网络的状态进行自适应传输,而且同时执了差错... 详细信息

由于无线信道的时变特性和移动设备有限的能量资源,保证无线网络视频流传输的Qos是一项比较困难的任务。文章提出了一种基于无线网络的视频流自适应传输架构。这个架构不仅动态的估计了无线网络的状态进行自适应传输,而且同时执了差错控制和功率控制。通过分析网络的状态和视频流的特性来动态分配资源,提高了端到端的QoS。

关键词：无线视频自适应传输功率控制 QoS

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家兔甲状腺内淋巴管铸型扫描电镜观察

解剖学报 1995年第1期26卷 9-13页

作者：章明韩永坚浙江医科大学解剖学教研室

用自行研制的水溶性淋巴管铸型剂（合成树脂三元共聚体的乳状溶液，共聚体含量占５０％），作器官实质注射，得到完整的兔甲状腺淋巴管铸型。甲状腺内淋巴管比相应的血管粗大，形状不规则。最显著的特点是许多淋巴管呈囊状膨大，且多位... 详细信息

用自行研制的水溶性淋巴管铸型剂（合成树脂三元共聚体的乳状溶液，共聚体含量占５０％），作器官实质注射，得到完整的兔甲状腺淋巴管铸型。甲状腺内淋巴管比相应的血管粗大，形状不规则。最显著的特点是许多淋巴管呈囊状膨大，且多位于小叶之间，称淋巴小囊，其大小与形状变化较大。这些淋巴小囊与其他淋巴管相互连接，构成三维的淋巴管系统，淋巴管铸型中呈盲端的淋巴管及一些淋巴小囊属于起始淋巴管（ｉｎｉｔｉａｌｌｙｍｐｈａｔｉｃｓ）。

关键词：淋巴管铸型剂甲状腺扫描电镜

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面对面和计算机群体决策运用排序法上的比较

心理科学 2004年第2期27卷 304-306页

作者：郑全全肖虹浙江大学心理学系杭州310028

通过人员选拔的实验室模拟实验,比较面对面的和以计算机为中介的决策群体在信息是否完全分享及是否采用排序法决策条件下对于决策效标的影响。结果表明:(1)决策前的信息分享通过决策前偏好的人数构成影响了最终的决策准确率。(2)排序法... 详细信息

通过人员选拔的实验室模拟实验,比较面对面的和以计算机为中介的决策群体在信息是否完全分享及是否采用排序法决策条件下对于决策效标的影响。结果表明:(1)决策前的信息分享通过决策前偏好的人数构成影响了最终的决策准确率。(2)排序法在面对面交流时只在信息非分享的情况下才显著增加了关键信息交流;排序法在计算机交流和信息完全分享下显著增加了关键信息交流。弥补了Hollingshead的研究不足之处。排序法不损害成员对于讨论的满意感。(3)计算机交流更关注文本信息,有更多争论、自我观点阐述和申诉。在关键信息交流上与面对面交流没有差异。(4)在决策准确性上,不同的交流方式没有差异。

关键词：面对面群体计算机群体决策排序法实验室模拟实验信息交流冒险性倾向产生式障碍决策效能

Influence of supports on the oxidation of glucose on nano-gold catalysts

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Influence of supports on the oxidation of glucose on nano-go...

变形链球菌黏附对2种不同抛光方式的纯钛、钛合金表面腐蚀的影响

2011 World Congress on Engineering and Technology(CET 2011)

作者： Yue Tang 1 Mingqiao Zhu 2 Lin Huang 3 Yangyi Shen 4 Yangyang Yang 5 department of Chemical and Biochemical Engineering zhejiang university hangzhou china.310027

Several kinds of nano-gold catalysts such as Au/TiO 2 ,Au/γ-Al 2 O 3 ,Au/SiO 2 and Au/MCM-41 were prepared by deposition precipitation method,using chloroauric acid as *** effects of supports on the catalytic performance for glucose oxidation were investigated and the catalysts were characterized by Transmission electron Microscope （TEM）,X-Ray Diffraction （XRD）,Inductively Coupled Plasma-Atomic Emission Spectrometry （ICP-AES） and BET *** better catalyst is Au（1.0 wt%）/TiO 2 and the glucose conversion of approximately 100% in 1.5h was obtained.

关键词： glucose oxidation sodium gluconate gold catalyst

来源： cnki会议评论

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上海口腔医学 2008年第6期17卷 633-637页

作者：沈晓艇刘丽莫康楠章燕珍梁伯贵浙江大学医学院附属口腔医院修复科浙江杭州310006

目的:研究在厌氧环境下变形链球菌粘附对2种抛光方式的纯钛及钛合金表面腐蚀的影响。方法:将牙科用纯钛、钛合金材料制备成30mm×8mm×1mm板片,各32片,分为2组,分别进行机械抛光和电化学抛光。再将每组试件随机分为空白对照组、培养基... 详细信息

目的:研究在厌氧环境下变形链球菌粘附对2种抛光方式的纯钛及钛合金表面腐蚀的影响。方法:将牙科用纯钛、钛合金材料制备成30mm×8mm×1mm板片,各32片,分为2组,分别进行机械抛光和电化学抛光。再将每组试件随机分为空白对照组、培养基对照组、3个月实验组和6个月实验组。将试件放入各组对应的试管,置于95%N2、5%CO2、37℃环境中,细菌每周传代1次,试件按各组预定时间取出,消毒灭菌。以表面轮廓仪测试各组试件表面粗糙度变化,扫描电镜观察各组试件表面形态变化,采用SPSS11.0软件包对结果进行方差分析。结果:纯钛实验组较对照组粗糙度无显著差异(P>0.05),钛合金实验组较对照组粗糙度有显著差异(P<0.05)。同种材料2种抛光方式下的实验组和对照组粗糙度变化无显著差异。扫描电镜下可见纯钛及钛合金试件表面存在腐蚀,纯钛表面腐蚀孔较钛合金少。结论:变形链球菌黏附对纯钛、钛合金表面产生腐蚀,单纯机械抛光和电化学抛光对变形链球菌腐蚀作用的影响无显著差异。

关键词：变形链球菌微生物腐蚀电化学抛光表面粗糙度