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Diode pumped Nd: YVO_4.laser at 671 nm with a type-Ⅱ noncritical phase-matched LBO

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chinese Science Bulletin 1999年第15期44卷 1363-1366页

作者： ZHANG Hengli , HOU Wei , WANG Jianming , XU Yao , XU Zuyan WU Baichang CHEN ChuangtianLaboratory of Optical Physics , institute of Physics , chinese academy of sciences , {2. 100080, china Fujian institute of Research on the Structure of Matter , chinese academy of sciences , Fuzhou 350002. china

A diode pumped intracavity frequency-doubled Nd: YVO4.laser emitting at 671 nm with a type- Ⅱ noncritical phase-matched LBO crystal is reported. A maximum output power at 671 nm of 4.4.mW was obtained under an incide... 详细信息

A diode pumped intracavity frequency-doubled Nd: YVO4./sub> laser emitting at 671 nm with a type- Ⅱ noncritical phase-matched LBO crystal is reported. A maximum output power at 671 nm of 4.4.mW was obtained under an incident pump power of 5.16 W, with an optical-to-optical conversion efficiency up to 7.8%. The output power fluctuates less than 5% while the temperature change of the LBO crystal is maintained at ± 0.5℃ at the phase-matched temperature.

关键词： LBO crystal Nd: YV04 crystal diode pump noncritical phase-match.

一种基于证据理论的中国手语单手静态词识别方法

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系统仿真学报 2008年第22期20卷 6142-6145,6150页

作者：邹伟杜清秀原魁徐萍萍中国科学院自动化研究所高技术创新中心北京100190 北京工业大学电控学院电工电子中心北京100022

单手静态词是中国手语词汇库的一个重要组成部分,该类词主要借助于单手的固定姿态和手同身体之间的相对位置关系进行表达。结合单手静态词的特点,提出了一种基于D-S证据理论的中国手语单手静态词汇识别方法:利用数据手套CAS_Glove获取... 详细信息

单手静态词是中国手语词汇库的一个重要组成部分,该类词主要借助于单手的固定姿态和手同身体之间的相对位置关系进行表达。结合单手静态词的特点,提出了一种基于D-S证据理论的中国手语单手静态词汇识别方法:利用数据手套CAS_Glove获取手姿信息,借助于视觉和肘部弯曲传感器融合确定出手在人体空间中的相对位置;在对单手词进行模糊特征空间划分的基础上,利用D-S证据理论实现了多种特征匹配结果的融合。为减少计算复杂度,增强系统实时性,对Dempster规则在特定条件下进行了简化,并从理论的角度对其进行了证明。最后通过实验比较证实了该方法的有效性。

关键词：证据理论单手静态手语词特征匹配识别

Analysis of F, Al, Mn, Zn, Fe, Cu, Ca and Mg concentrations in brick teas from main producing areas in china

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chinese Journal of Geochemistry 2006年第S1期 80-81页

作者： Xiaoyu ZHAO, Wuyi WANG, Hairong LI, Fujian FENG, Lizhen WANG institute of Geographical sciences and Natural Resources Research,{2., beijing 100101,{4.

An Improved Genetic Algorithm for Mobile Robotic Path Planning

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An Improved Genetic Algorithm for Mobile Robotic Path Planni...

第2.届中国控制与决策会议

作者： Zhou Yongnian 1, 2., Zheng Lifang 1 , Li Yongping 1 1. Shanghai institute of Applied Physics, chinese academy of sciences, Shanghai, 2.12.4.{2.2. The Graduate School of chinese academy of sciences, beijing, 100039,{2.

Proposed an improved genetic algorithm based on rough sets reduction theory, optimized the genetic operators, and overcame the weakness of the traditional genetic algorithm, such as huge number of initial population and slow velocity of optimization and convergence. The experiments both in simple and complex environment have been carried on. The simulation result indicated that the method can reduce the scale of the population, minimize the searching scope, and improve the velocity of the convergence and optimization for the mobile robotic path planning.

关键词： Mobile Robot Path Planning Rough Set Genetic Algorithm

并行数据库系统PBASE/2.查询优化机制

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计算机工程 2000年第7期26卷 11-12,187页

作者：陈红王珊文继荣中国人民大学数据与知识工程研究所北京100872 中国科学院计算技术研究所北京100080

并行查询执行计划的搜索空间里指数级增长，如何高效地裁剪搜索空间是并行查询优化的关键所在。ＰＢＡＳＥ／２以流机制为基础，采用基于代价估算和启发式规则的改良的两阶段优化技术，有效地解决了这一问题。

关键词：流机制并行数据库系统查询优化 PBASE/2

Acoustic Experiments and Rock Geophysical Models for Gas Hydrate Sediments

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Acoustic Experiments and Rock Geophysical Models for Gas Hyd...

第二届大陆边缘构造和资源国际学术研讨会

作者： WangDong~1 WangXiuming~1 LiDongliang~2.Zhang Hailan~1 Fan Shuanshi~2.1 institute of Acoustics chinese academy of sciences {2. 100080 china) 2.Guangzhou Center for Gas Hydrate Research and Guangzhou institute of Energy Conversion academy of sciences Guangzhou 51064. china

＜正＞This paper report on P-wave velocity and attenuation measurements of artificial gas hydrate samples at low *** the temperature and pressure dependence of P- wave velocity has also been investigated.

关键词： Methane hydrate P-wave velocity Temperature Pressure Rock models

Meso-Cenozoic tectonothermal evolution of Ordos basin,central china:Insights from newly acquired vitrinite reflectance data and a revision of existing paleothermal indicator data

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Meso-Cenozoic tectonothermal evolution of Ordos basin,centra...

中国科学院地质与地球物理研究所2.07学术年会

作者： Yusong Yuan~(a,*),Shengbiao Hu~a,Hongjun Wang~b,Fenjing Sun~c a institute of geology and Geophysics,{2. academy of {4.,beijing 100029,china b Research institute of Petroleum Exploration,Petrochina,beijing 100083,china c Langfang Branch,Research institute of Petroleum Exploration and Development,CNPC,Langfang 065007,china

Thermal history reconstruction using paleogeothermal indicators,including vitrinite reflectance(Ro) and apatite fission track (AFT) dating in the Ordos basin indicates that the lower subsection,consisting of the Paleozoic to Middle Triassic sediments, reached its maximum paleotemperatures at the end of the Middle Triassic(T) and experienced a paleogeothermal gradient of 4.0}63℃/km with a mean of 4.±9℃/km,while the upper subsection from the Late Triassic to Middle Jurassic,experienced its maximum paleotemperatures at the beginning of Late Jurassic(J3) and a paleogeothermal gradient of 2.-39℃/km with a mean of 31±6℃/***,at least two heating events are recorded in the Ordos basin since the Mesozoic:the first and most intensive in Middle Triassic as recorded by the lower subsection,the other is a moderate Jurassic thermal event as recorded by the upper *** heating events were followed by a Cenozoic rapid cooling starting at about 2. *** the regional geodynamic context,the Triassic thermal event might be ascribed to hydrothermal activity related to the Triassic collision between the North china Block(NCB) and the South china Block(SCB);the Jurassic thermal event to the Pacific subduction and the Cenozoic rapid cooling event to the Indo-Asian collision,respectively.

关键词： Ordos basin Thermal history Paleo-geothermal gradient Tectonics Hydrothermal activity

On the“Eight-Class System”of the Angiosperms

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On the“Eight-Class System”of the Angiosperms

第七届全国系统与进化植物学青年学术研讨会

作者： FU De-Zhi (institute of Botany, chinese academy of sciences, {2. 100093)

Critical comments are provided on an "eight-class system" of the angiosperms, which claimed to be a "polyphyletic-polychronic-polytopic" system. This system is based on eight assumed principal evolutionary lineages existed at a truncated time section of the Early Cretaceous. However, it is lack of both fossil and theoretical evidence. There is little explanation on the relationship between each

关键词： Monophyletic polyphyletic angiospenn eight-class system

A direct and elementary proof of the stabilization for the wave equation with nonlinear internal damping

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A direct and elementary proof of the stabilization for the w...

第十九届中国控制会议

作者： Wei-Tao Zhang institute of Systems Science, academy of Mathematics and Systems Science, The{2., beijing 100080,{4..

Using a technique in [4.7] and some integral inequalities due to Haraux and Komornik, one gave a direct and elementaty proof of the stabilization for the wave equation with nonlinear internal damping, extended and uni... 详细信息

关键词： wave equation internal damping stabilization