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计算机工程与应用 2001年第4期37卷 21-22,111页

作者：张占军韩承德杨学良中国科学院计算技术研究所系统结构研究室北京100080 中国科学技术大学研究生院计算机学部北京100039

文章介绍了未来Ｉｎｔｅｒｎｅｔ中存在的两种服务模型，综合服务（Ｉｎｔ－Ｓｅｒｖ）和分类服务（Ｄｉｆｆ—Ｓｅｒｖ），并对它们进行了评价。

关键词： Internet 综合服务分类服务多媒体路由器

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论巴赫金文体进化观的成因及意义

思想战线 2002年第4期28卷 80-83页

作者：王珂北京师范大学中文系北京100875

巴赫金文体进化观是在他受到政治独裁和文体独裁双重压迫的特定历史语境下提出的 ,具有相当的合理性。巴赫金表面上是重视传统、秩序和法则的文体学家 ,实质上是激进的文体改革者。他对复调、杂语的重视 ,是为了通过对文体的多元化的吁... 详细信息

巴赫金文体进化观是在他受到政治独裁和文体独裁双重压迫的特定历史语境下提出的 ,具有相当的合理性。巴赫金表面上是重视传统、秩序和法则的文体学家 ,实质上是激进的文体改革者。他对复调、杂语的重视 ,是为了通过对文体的多元化的吁求来达到政治的多极化。借鉴巴赫金的文体理论 ,不但要弄清巴赫金文体理论生成的历史背景 ,还要正视中国的具体国情。

关键词：巴赫金文体自由法则文体进化

ACTIVE CONTROL OF WIND-INDUCED VIBRATION OF FEED SUPPORTING SYSTEM FOR LARGE SPHERICAL RADIO TELESCOPE USING ELECTRORHEOLOGICAL VARIABLE DAMPER

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ACTIVE CONTROL OF WIND-INDUCED VIBRATION OF FEED SUPPORTING ...

第一届国际机械工程学术会议

作者： Su Yuxin Duan Baoyan (School of Mechanical and Electronic Engineering Xidian university) Nan Rendong Peng Bo (beijing Astronomical Observatory chinese Science of {3.)

＜正＞ Based on the introduction of the electrorheological （ER） fluid and the various models of dampers using ER fluid,and considering wind induced vibration of the feed supporting system with cables for large spherical radio telescope,a novel ER damper is designed to realize the semi-active control of mis *** model of the designed ER variable damper is described detailed,and the strategy of the active control is *** numerical simulation results have shown the validity of the designed adaptive ER damper to suppress the wind vibration of the feed supporting system for next generation large spherical radio telescopes.

关键词： Electrorheological fluid Large spherical radio telescope Wind-induced vibration ER variable damper Active control of vibration

Invariant Joint Transform CorrelatorⅠ: Mapping Filter

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chinese Journal of Lasers 1997年第1期B6卷 64-70页

作者： FENG Jihong WU Minxian JIN Guofan YAN Shuhua(Tainghua university, Precision Department,100084.beijing, China) Tsinghua Univ Beijing China

A joint transform correlator incorporating coordinate transformation technique is propescd to perform invariant pattern recognition. Instead of an input image or its Fourier transform intensity, the Fourier transform of the input image is directly transformed from rectangular into logarithmic-polar coordinate. All of information is saved, and as a result, multiple objects can be proceased simulataneously. A binary optical component is designed and fabricated to perform coordinate transformation in high efficiency.

关键词： invariant optical pattern recognition cyclic shift joint transform correlator binary optical component

Major types,characteristics and geodynamic mechanism of Upper Paleozoic copper deposits in northern Xinjiang,northwestern China

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Major types,characteristics and geodynamic mechanism of Uppe...

中国科学院地质与地球物理研究所2006学术年会

作者： Chunming Han~a,Wenjiao Xiao~3.Guochun Zhao~b,Jingwen Mao~c,Sanzhong Li~d, Zhen Yan~a,Qigui Mao~a a State Key Laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,chinese academy of sciences,{3. 100029,P.R.China b Department of Earth sciences,The university of Hong Kong,Pokfulam Road,Hong Kong,China c Institute of Mineral Deposits,chinese academy of Geological sciences,26 Baiwanzhuang Road,{3., 10003.,P.R.China d College of Marine Geosciences,Ocean university of China,Qingdao 266003.Shangdong,P.R.China

Syn- and post-orogenic Cu mineralization in the northern Xinjiang Paleozoic accretionary and collisional orogenic belt in northwestern China is of great economic interest. About 4. Cu-bearing deposits have been discovered in the area,making it one of the most important metallogenic belts in *** to their host rocks,these deposits can be classified into four principal types:(1) volcanic-hosted massive sulfide Cu-Pb-Zn deposits;(2) porphyry Cu-Mo-(Au) deposits;(3. magmatic Cu-Ni sulfide deposits;and(4. Cu-Mo-Au-Ag skarn ***,the development of these Upper Paleozoic deposits was closely associated with subduction and collision of the ancient Asian Ocean between the Siberian Block and the Tarim *** important metallogenic epoch involving formation of Cu-Pb-Zn-polymetallic deposits formed during southwestern rollback and associated slab-detachment during Devonian time(4.0-3.0 Ma).In southern Altay,southwestern-direct rollback and associated slab-detachment occurred during the Devonian(4.0-3.0 Ma),in response to later collision at the accreted continetal margin[Xiao,W.J.,Windley,B.F.,Badarch,G.,Sun,S., Li,J.L.,Qin,K.Z.,Wang,Z.H.,*** accretionary and convergent tectonics of the southern Altaids:implications for the lateral growth of Central *** of the Geological Society of London 161,3.9-3.0}],during which the Ashele Cu-Pb-Zn and Keketale Pb-Zn deposits *** led to the accretion of the Junggar Ocean arc system in the Middle *** the Lower to Middle Carboniferous,north-dipping subduction beneath the Dananhu arc triggered the emplacement of granitic porphyries in the Tousuquan and Dananhu island arc belt in the east Tianshan,leading to the formation of the Tuwu and Yandong porphyry Cu-Mo-Au-Ag *** the Upper Carboniferous to Lower Permian,large mafic-ultramafic complexes were emplaced during closure of the ancient Tianshan Ocean,resulting in the formation of several magmatic Cu-Ni sulfide deposi

关键词： Copper deposits Metallogenic belts Tectonic setting Xinjiang China

The synthesis and crystal structure of heteronuclear complex of lanthanide with sulfo-salicylic acid [Na3.La2(C7H3.O6)4.26H2O]n

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chinese Journal of Chemistry 1995年第2期13卷 150-155页

作者： SUN, Hong-Ye HUANG, Chun-Hui GAN, Liang-Bing XU, Guang-XianState Key Laboratory of Rare Earth Material Chemistry and Applications, Peking university, beijing 100871, ChinaMA, Zhe-Sheng SHI, Ni-Cheng China university of Geoscience, beijing 100083.China China university of Geoscience Beijing 100083 China

The titled complex has been synthesized by the reaction of sodium sulfo-salicylate with lanthanum and yttrium perchlorate. The crystal structure has been determined by single crystal X-ray diffractometry. The crystal is monoclinic with space group C2/c. The unit cell parameters are as follows: a=16.289(8), b=18.3.3.8), c=22.04.(8) A, β=106.3.0}2)°, V=63.4.6) A3. Z=4.and Dc=1.764.g/cm3. The structure was solved by direct method. The least-square refinement based on 3.76 observed reflections [F > 6σ(F)] converged to a final R=8.6% and F(000) is 3.4.. Yttrium ion with eight-coordinate is located in central of the molecule, the two lanthanum ions with ten-coordinate are located at the two sides of yttrium ion. There are two positions for Na in the molecule, one is in the C2 axis with six coordinate, the other one is in a general position with five-coordinate.

关键词： Crystal structure heteronucleax complex lanthanide elements sulfo-salicylic acid.

Synthesis and Fluorescence Quenching of Copolymer Containing3. 4. 9, 10-Perylenetetracarboxyl Diimide Side Chains

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chinese Chemical Letters 1999年第11期10卷 953-956页

作者： Zhao ZHANG Zhao Bin CHEN Feng Lian BAI Yue Ping ZHANG Yi Ming MO Min ZHENG Xiao Lin YAN Yu hang LI(Department of Chemistry, Shanxi university, Taiyuan 03.006)(Lab of Organic Solid, Institute of Chemistry, academy Sinica, beijing 100080) Shanxi Univ Dept Chem Taiyuan 030006 Peoples R China Acad Sinica Inst Chem Lab Organ Solid Beijing 100080 Peoples R China

A photoluminescence material, copolymer of N-vinylcarbazole (VCz) and N,N'- bisallyl-3. 4. 9, 10-ferylenetetracarboxyl diimide (APTC) chromophores P(VCz-APTC) was synthesized. The fluorescence quenching of P(VCz-APTC)... 详细信息

关键词： 3. 4. 9, 10-perylenetetracarboxyl diimide copolymer fluorescence quenching

Robust Stabilization of a Class of Nonlinear Networked Control Systems

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Robust Stabilization of a Class of Nonlinear Networked Contr...

第25届中国控制会议

作者： Sun Jian,Liu Guoping Institute of Automation,chinese academy of sciences,{3. 100080 School of Electronics,{4. of Glamorgan,Pontypridd CF3. 1DL,UK NCS Lab in the Central South {4.,Changsha,4.0083.China

＜正＞This paper is concerned with the robust stabilization problem for a class of networked control systems with nonlinear perturbations. The perturbations are assumed to be time-varying and satisfying quadratic constraints. Such networked control systems are modeled as systems with time-varying delays. Based on this model, observerbased controllers are designed to stabilize the nonlinear systems subject to the network-induced delay and data dropout. Sufficient conditions on existences of the stabilizing controllers are established. The controller gains can be obtained by solving a set of linear matrix inequalities. An illustrative example is given to demonstrate the effectiveness of the proposed method.

关键词： Networked control systems Network-induced delay Linear matrix inequality (LMI) Stability

Changes in hot days and heat waves in China during 1961-2007

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Changes in hot days and heat waves in China during 1961-2007

作者： Ting Ding,~a Weihong Qian~(a*) and Zhongwei Yan~b a Monsoon and Environment Research Group,Department of Atmospheric sciences,School of Physics,Peking university,beijing,China b Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,{3. {4. of sciences,beijing,China

Based on the daily maximum temperature(DMT) records at 512 stations during 1961 -2007,the geographical patterns and temporal variations of hot days(HDs) and heat waves(HWs,including those persisting for 3.5 days and longer) over China’s mainland were *** HD(and hence HW) was defined in two ways,one by an absolute criterion,DMT >3.℃,as applied in the nationwide meteorological agencies and another in a relative sense,DMT > the 90th percentile threshold of a local daily temperature distribution around the *** centers of high frequencies(over 5 days per year) of the absolute HDs during June-September were found in the regions of Xinjiang and the mid-lower reaches of the Yangtze *** highest frequencies of the absolute HWs were about 1.5 times per year in the Xinjiang region and to the south of the mid-lower reaches of the Yangtze *** frequencies of the relative HWs were about 1-1.5 times per year in most of *** HDs and HWs increased significantly during the studied period in most of China,especially over the southeastern coast and northern China(by over 4.days per decade for relative HDs and 0.4.times per decade for relative HWs),but decreased significantly at some stations in the lower reaches of the Yellow *** most of China except northwestern China,the frequency of HDs was high during the 1960s-1970s,low in the 1980s,and high afterwards,with strong intcrannual variations.A remarkable increasing trend of HDs occurred after the 1990s in all *** changes in HDs and HWs were closely related to those in rain days and atmospheric circulation patterns at the interannual and interdecadal *** ? 2009 Royal Meteorological Society

关键词： climate extremes climate trend hot days heat waves China

甲烷催化部分氧化制合成气固定床反应器的研究进展

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石油与天然气化工 2008年第2期37卷 105-109,114页

作者：刘淑红陈燕馨徐恒泳王玉忠李文钊中国科学院大连化学物理研究所

简要回顾了合成气的生产历史。与传统的甲烷水蒸气重整制合成气相比,甲烷催化部分氧化制合成气在过程能耗和产物组成等方面具有一定的优势,反应器是甲烷催化部分氧化制合成气工艺过程的关键。本文对1990年以来甲烷催化部分氧化制合成气... 详细信息

简要回顾了合成气的生产历史。与传统的甲烷水蒸气重整制合成气相比,甲烷催化部分氧化制合成气在过程能耗和产物组成等方面具有一定的优势,反应器是甲烷催化部分氧化制合成气工艺过程的关键。本文对1990年以来甲烷催化部分氧化制合成气8种新型结构固定床反应器进行了归纳和评述。

关键词：甲烷催化部分氧化合成气反应器