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ENHANCED MULTISTAGE VECTOR QUANTIZATION FOR SAR RAW DATA COMPRESSION

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Journal of Electronics(china) 1996年第2期13卷 97-101页

作者： Zhu Minhui Peng Hailiang Wu Yirong Qi Xuan(institute of Electronics, chinese academy of sciences, beijing 100080)

Multistage Vector Quantization(MSVQ) can achieve very low encoding and storage complexity in comparison to unstructured vector quantization. However, the conventional MSVQ is suboptimal with respect to the overall performance measure. This paper proposes a new technology to design the decoder codebook, which is different from the encoder codebook to optimise the overall performance. The performance improvement is achieved with no effect on encoding complexity, both storage and time consuming, but a modest increase in storage complexity of decoder.

关键词： Vector quantization Data compression Synthetic aperture radar

Selective Cyclooxygenase-2 Inhibitors: Design and Synthesis

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chinese Chemical Letters 1999年第6期10卷 469-472页

作者： Xin Sheng LEI Zong Ru GUO Ling Bo QU Qi Qing ZHU(institute of Materia Medica. chinese academy of Medical sciencesAnd Peking Union Medical College. beijing 100050) chinese Acad Med Sci Inst Mat Med Beijing 100050 Peoples R China Peking Union Med Coll Beijing 100050 Peoples R China

The discovery of COX-2 provides a novel target developing more effective NSAIDs with fewer side effects. On the basis of results from the structure-activity relationships (SAR) of selective COX-2 inhibitors, we have d... 详细信息

关键词： cyclooxygenase cyclooxygenase-2 inhibitor selective

Tectono-chronologic constraints on a Mesozoic slip and thrust belt in the eastern Jiaodong Peninsula

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Science china Earth sciences 2007年第1期50卷 25-32页

作者： ZHANG HongYuan1,2, HOU QuanLin3 & CAO DaiYong 4 1 institute of geology, chinese academy of Geological sciences, beijing 100037, china 2 State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, beijing 100083, china 3 Graduate School of china Acacemy of sciences, beijing 100039, china 4 Key Laboratory of Coal Resources (CUMT), Ministry of Education, beijing 100083, china 1. institute of geology Chinese Academy of Geological Sciences Beijing 100037 China 2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 3. Graduate School of china academy of sciences Beijing 100039 China 4. Key Laboratory of Coal Resources (CUMT) Ministry of Education Beijing 100083 China

A major slip and thrust belt within the eastern Jiaodong Peninsula is located at the eastern terminal of the Qinling-Dabie-Sulu orogenic belt between the Sino-Korea Block and Yangtze Block. Although a lot of isotope chronologic data have been obtained regionally, little structural chronological research has been conducted in this region and this paper corrects that. Syn-deformational minerals were system-atically selected from samples of the NE-ENE trending transpressional shear zones and transpres-sional nappes and carefully analysed using 40Ar/39Ar methods. Two tectonic events were defined with the first event resulting from early movement of transpressional nappes around 190 Ma ago. This ac-cords with the period of syn-orogenic sinistral slip of the Tan-Lu faults and clockwise shear in the Eastern Qinling-Tongbaishan part of the Qinling-Dabie-Sulu orogenic belt. The second event involved strikeslip thrust movement of deep shear zones between 130Ma and 120Ma. This resulted from the onset of Mesozoic tectonic conversion in the eastern Jiaodong Peninsula. The sinistral strikeslip-thrusting in Jiaodong Peninsula and the extensional tectonism (toward ESE) in Liaodong Peninsula probably resulted in the clockwise rotation of Korea Peninsula in late Mesozoic.

关键词： the eastern Jiaodong Peninsula tectono-chronology 40Ar/39Ar strikeslip and thrust belt.

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回眸中国古代地方政治的贪腐与黑暗

史学集刊 2011年第1期 3-19页

作者：王曾瑜中国社会科学院历史研究所北京100021

以马克思主义对等级授职制批判为指导,分五个方面对古代地方政治的主流予以回顾和总结。强调历朝历代地方政治的贪腐与黑暗,简直就是在一个模子里刻出来的。这个模子非它,就是专制主义中央集权的等级授职制,各种贪腐与黑暗的遗传密码正... 详细信息

以马克思主义对等级授职制批判为指导,分五个方面对古代地方政治的主流予以回顾和总结。强调历朝历代地方政治的贪腐与黑暗,简直就是在一个模子里刻出来的。这个模子非它,就是专制主义中央集权的等级授职制,各种贪腐与黑暗的遗传密码正是在这个模子里得到了世世代代的传承和发扬。研究中国古代地方政治,正是为了将古代地方政治制度史,写成活的地方政治制度史。在一般情况下,信息传递对地方政治的好坏,其作用是相当次要的。

关键词：地方政治等级授职制等级授官人治贪腐

COMPILATION OF HEAT FLOW DATA IN THE china CONTINENTAL AREA (2nd Edition)

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地震地质 1990年第4期 364-366页

作者： Wang Ji-yang and Huang Shao-peng(institute of geology, Academia Sinica, beijing 10002.)

During the last 2 years, heat flow data increased significantly in china as a result of implementation of many comprehensive geodynamic (including geothermal) projects and GGT project in china. In this paper, a total of 366 reliable heat flow data is collected from published and in press sources in the Compi-ilation of Heat Flow Data in the china Continental Area (2nd edition). Statistic analysis of these data shows that the heat flow values in china continental area vary from 20 to 140 mWm-2. The mean value appears to be 66 mWm-2.

关键词： Heat flow data Quality category Data distribution china continental area

Photoluminescence Properties of Porous Silicon Based on FZ(H) Si Wafer

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Rare Metals 2001年第1期20卷 38-42,57页

作者： Yuejiao He, Huaixiang Li, Chenghua Guo, Guirong Liu, Yansheng Chen, Shuzhen Duan (institute of Semiconductors, Shandong Normal University, Jinan 250014, china Metallurgy School, University of Science and Technology beijing, beijing 100083, china) Shandong Normal Univ Inst Semicond Jinan 250014 Peoples R China Univ Sci & Technol beijing Met Sch Beijing 100083 Peoples R China

The photoluminescence (PL) properties of porous silicon (PS) have been studied based on n-type single-crystal (111) silicon wafers (80-90 Omega .cm in the resistivity). The porous silicon layers (PSL) were created by anodizing the wafers with a denuded zone of 20-40 mum formed by neutron transmutation doping (NTD) and thermal treatment at 940 degreesC for 4 h and then 700 degreesC for 2 h, two-step heating of the floating-zone silicon (FZ Si) grown in a hydrogen (H,) ambience. By surface modification with stannic chloride or amine immersion and rapid thermal oxidation (RTO), the PL peak position from the PS can be qualitatively controlled factitiously. The as-prepared PS shows an orange-yellow luminescence, while the modified samples emit red, green and blue luminescence. Mechanisms for the different colors of the PL are discussed. Fourier transform infrared (FTIR) is carried out to analyze the differences in the structural configuration of the PS samples.

关键词： porous silicon photoluminescence surface modification rapid thermal oxidation

Clifford Algebras and Homogeneous Geometric Models

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Clifford Algebras and Homogeneous Geometric Models

EXPLOSIVE CONSOLIDATION OF METALLIC FILAMENTS UNDER CYLINDRICAL CONVERGING SHOCK WAVE

CCAST“蛋白质结构分析中的一些问题”研讨会

作者： Hongbo Li academy of Mathematics and System sciences chinese academy of sciences beijing 100080, china Email:hli@***

＜正＞ 1 IntroductionThis paper is based on a talk at the First Conference on Protein Structure in beijing, November 18-22, 2002, and another talk at the Seminar held by Prof. Ke Wu in the institute of Theoretical Physics of the chinese academy of sciences. beijing, December 19, *** talks are on an "old" algebraic language - Clifford algebra, and its applications in geometric computing. Clifford algebra has a history of about 150 years. Its modern definition is as follows.

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Acta Metallurgica Sinica(English Letters) 1991年第8期4卷 121-126页

作者： GAO Juxian SHAO Binghuang ZHANG Ke ZHENG Zhemin institute of Mechanics,Academia Sinica,beijing,china Acad Sinica Beijing China

Two dimensional explosive consolidation under cylindrical converging shock wave has been studied by use of coated fine iron filaments compacts to replace conventional metallic powder, so the randomness of three-dimensional spatial distribution of metallic powder might be *** deformation and surface flow pattern of particles as well as the mechanism of consolidation have been clarified *** distribution of high temperature area is in agreement with the result of numerical simulation by Williamson.A model for the explosive consolidation was given.

关键词： explosive consolidation shock wave metallic powder

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基于DSP56F805的PWM实现

微特电机 2004年第1期32卷 18-20页

作者：奚正平中国科学院电工研究所北京100080

介绍了脉宽调制技术和DSP5 6F80 5内置的PWM模块 ,并通过编程实例和实验、仿真结果说明了该模块的应用方法。

关键词： DSP56F805 PWM 脉宽调制电气传动系统永磁同步电机矢量控制