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Chinese science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2, XIA Ming1, KU Tehlung2, PENG Zicheng3. CHEN Yushu4.& ZHANG Zhaofeng3.1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 2. {3. of Earth sciences, University of Southern California, Los Angeles, CA90089-074., USA 3. {3. of Earth and space science, University of science and technology of china, Hefei 23.026, china 4. Beijing Foshan Tourist Service Centre, Beijing 1012.1, china Institute of Geology and Geophysics. Chinese Academy of sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern Beijing over the past 3.00 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3.00—2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3.00 years. During 500—200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13., Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3.00年

Monitoring of rice crop using ENVISAT ASAR data

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science china Earth sciences 2006年第7期49卷 755-763页

作者： DONG Yanfang1, 2, SUN Guoqing1,3.& PANG Yong4.1. State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, Beijing 100101,{3. 2. Graduate University of Chinese Academy of sciences, Beijing 10003.,{3. 3. department of Geography, University of Maryland, College Park, MD 2074., USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information technology, Chinese Academy of For-estry, Beijing 100091,{3. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of sciences Beijing China department of Geography University of Maryland College Park USA Forest Remote Sensing Lab Research Institute of Forest Resource and Information Technology Chinese Academy of Forestry Beijing China

Because of the cloudy conditions during the rice growth period, rice is one of the agri-cultural crops most suited to monitoring with the SAR instruments. Backscatter response measured by SAR is correlated with rice conditions, including height, density, biomass and structure, which are variable at different growing stages. In this paper, multi-date ENVISAT ASAR Alternating Polarization Mode (APMode) imageries were acquired during the rice crop growing cycle. At the same time, the rice parameters were measured in field. A continuous canopy model was used to compute the back-scattering from rice fields during the growth cycle, and the relationship between rice parameters and radar backscattering coefficients from both ASAR and modeling was analyzed. The effects of polari-zation, incidence angle and polarization on radar backscattering coefficients were analyzed. It was found that simulated radar backscatter has similar trends as ASAR data. This will be meaningful for the further research of rice parameters estimation from ASAR data. Different features show signifi-cantly different signatures in ASAR images and they follow some certain laws, so rice area can be accurately mapped by using multi-temporal SAR images, then rice yield can be estimated.

关键词： rice, ASAR, radar backscattering, model.

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3. HUANG Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, china 2. School of Information science and Engineering, Shandong University, Jinan 250100, china 3. department of Chemical Engineering, Light Industry College of Shandong, Jinan 250100, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong University of science and technology, Wuhan 4.0074. china State Key Laboratory of Crystal Materials Shandong University Jinan China School of Information science and Engineering Shandong University Jinan China department of Chemical Engineering Light Industry College of Shandong Jinan China Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 {3. group, while NEt-1 to non-centrosymmetric polar Cc {3. group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 {3. group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Sm-Nd isotopic ages of Tiqiushan eclogites in Xinyi region and its geological significance

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Chinese science Bulletin 1999年第S2期44卷 144-146页

作者： WANG Yinxi~(1,2), YANG Jiedong~(1,2), TAO Xiancong~(1,2), GE Ningjie~4. CHEN Peirong~3. FAN Chunfang~3.and LI Jianhua~5 1. Center of Modern Analysis, Nanjing University, Nanjing 210093. china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing University, Nanjing 210093. china 3. {3. of Earth science, Nanjing University, Nanjing 210093. china 4. {3. of Earth and space sciences, University of science and technology of chian, Hefei 23.026, china 5. No.5 Geological Party of Jiangsu Province, Xuzhou 221005, china Center of Modern Analysis Nanjing University Nanjing 210093 China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China department of Earth and space sciences University of Science and Technology of Chian Hefei 230026 China department of Earth science Nanjing University Nanjing 210093 China No. 5 Geological Party of Jiangsu Province Xuzhou 221005 China

GEOLOGICAL scientists have paid much attention to the suture zones formed by collision between the Sino-Korean and Yangtze blocks because of the discovery of the ultrahigh pressue metamorphic (UHPM) rocksfrom northern Jiangsu Province (Su), southern Shandong Province (Lu) and the Dabie *** the age of 200-24. Ma is probably the best estimation for UHPM metamorphism in the DabieMountains, the primary intrusive and metamorphic ages of the complex from northern Jiangsu Provincehave not been determined before. Using the Sm-Nd isotopic dating method, our study is aimed at datingthe UHPM metanorphic event of northern Jiangsu Province and researching a probable relation between theUHPM rocks from the Dabie Mountains and the UHPM rocks from northern Jiangsu Province.

关键词： northern Jiangsu eclogite rocks Sm-Nd isotopic ages.

Study of Product Quality Information and Construction of Its Decision-Making Support System and Measures to Improve People's Quality Concept

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厦门大学学报（自然科学版） 2002年第S1期41卷 234-235页

作者： RUAN Jin-yuan 1, SUN Shu-tao 2, YU Xin-qi 2, RUAN Xin 3.(1. Ordance Institute of General Equipment department, Shijiazhuang 05 0000, china 2. Graduate School of Chinese Academic of science, Beijing 1000{3., china 3. East china University of science and technology, Shanghai 20023., china {3. Meterology Bureau of Hebei Province, Shijiazhuang 050021, china)

The 21th century is a "quality century". Facing the s evere challenge about quality, all the developed industry countries attach impor tance to the research and education about quality project. With the deepening of the reform of china and it’s joining to WTO, many industries and enterprises wi ll be confronted with severe challenge while being offered the opportunity to wa lk up to the world. The arrival of knowledge economy and web time has provided t he space for the innovation on enterprise management. It has also provided new m ethod and model for enterprise management, that is online management based on th e internet. The online management use an enterprise model including the goal of the enterprise and the scheme to carry out it to represent the whole operational of all the work. The online management is constructed on the integration of exp ert system, database, software and other technical models. How to scientifically manage the entire system of product, precisely master the condition of quantity and quality and analyze the rules of the change of produc t quality in order to carry out the overall control of quality, guarantee the go od condition of product as well as improve product quality and prolong it’s se rvice life was discussed in this thesis. Based on the above research the thesis also discussed how to develop the study on product quality information and const ruct it’s decision making support system. The concrete measures to improve peopl e’s concept of quality are also raised. Based on the type analysis, scientific management of product quality information should start from dynamic information of quality, instruction information as we ll as the information about the use, maintain, management and conservation of pr oduct, and induce them and further propose a design scheme of feedback system on product quality information, and then set up the blueprint of the information s ystem of product quality. This thesis included 7 chapters:*** type of qua

关键词： product guality information decision-making sup port system of management of guality information people’s guality concept

Fuzzy tolerance quotient spaces and fuzzy subsets

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science china(Information sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2,3.4. 1Computer science & technology College, Anhui University, Anhui 23.03.,{3. 2State Key Laboratory of Intelligent technology and Systems, Beijing 100084.{3. 3.singhua National Laboratory of Information science & technology, Beijing 100084.{3. 4.nformation science & technology College, Computer science & technology {12., Tsinghua University, Beijing 100084.{3. Computer science & technology College Anhui University State Key Laboratory of Intelligent technology and Systems Tsinghua National Laboratory of Information science & technology Information science & technology College Computer Science & Technology

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2) the definition of isomorphism of fuzzy tolerance relations; (3. the isomorphic discriminant of fuzzy tolerance relations; (4. the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

TOPOLOGICAL CONFIGURATIONS OF POSSIBLE REAL NETS IN BINARY n+m(m≥3. PHASE MULTISYSTEMS

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science in china,Ser.B 1986年第10期29卷 1096-1109页

作者：程伟基 department of Earth and space sciences University of science and technology of china Hefei

This paper further summarizes the method and results developed to find all possible real nets in binary n+3.phase multisystems, and emphasizes that there is a definite relationship between configurations and symbols of stable and metastable invariant points of nets or positions of phases as symbols on the chemographic bar. On the basis of these, a general principle is developed to construct and check possible neets in binary n+m (m>3. phase multisysterns: this sort of nets must be the reasonable combination of one or more than one distinct binary n+3.phase multisystem subnets, in which the number of points missing respectively same m—3.phases in n+3. Therefore, the binary n-4.3.phase nets are basic construction units of the binary n+m(m>3. phase nets. As an instance, the maximum partially closed net in binary n+4.phase multisystems, which has the most stable invariant points, is constructed, and it is indicated that this sort of net is unique.

关键词： PHASE MULTISYSTEMS TOPOLOGICAL CONFIGURATIONS OF POSSIBLE REAL NETS IN BINARY n+m net NETS

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2,3.& ZHANG Xin1,4.1Kavli Institute for Theoretical Physics china,Chinese Academy of sciences,Beijing 100190,{3. 2Key Laboratory of Frontiers in Theoretical Physics,Institute of Theoretical Physics,Chinese Academy of sciences,Beijing 100190,{3. 3.nterdisciplinary Center for Theoretical Study,University of science and technology of china,Hefei 23.026,{3. 4.9} of Physics,College of sciences,Northeastern University,Shenyang 110004.{3. Kavli Institute for Theoretical Physics china Chinese Academy of Sciences Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Interdisciplinary Center for Theoretical Study University of Sc

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

Competent predicate abstraction in model checking

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science china(Information sciences) 2011年第2期54卷 258-267页

作者： LI Li1,2,3. SONG XiaoYu4. GU Ming2,3.& LUO XiangYu2,3.1department of Computer science & {3., Tsinghua University, Beijing 100084. china 2Key Laboratory for Information System Security, Ministry of Education of china, Beijing 100084. china 3.chool of Software, Tsinghua University, Beijing 100084. china 4.0} of ECE, Portland State University, Portland, Oregon 97207, USA department of Computer science & technology Tsinghua University Key Laboratory for Information System Security Ministry of Education of China School of Software Tsinghua University department of ECE Portland State University

The paper presents a new approach to computing the abstract state and a maximum weight heuristic method for finding the shortest counter-example in verification of imperative programs. The strategy is incorporated in a verification system based on the counterexample-guided abstraction refinement method. The proposed method slashes both the size of the abstract state space and the number of invokes of a decision procedure. A number of benchmarks are employed to evaluate the effectiveness of the approach.

关键词： program model checking predicate abstraction weight heuristic

Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2, QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4. WANG GuangLi1, ZHENG WeiMin1, GUAN Di3. ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, JIANG DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, Chinese Academy of sciences, Shanghai 20003., china 2 Center for {3. science and Applied Research, Chinese Academy of sciences, Beijing 100190, china 3.Lunar Explorer Engineering General department, Chinese Academy of sciences, Beijing 100012. china 4.Beijing Institute of Tracking and Telecommunications technology, Beijing 100094. china Shanghai Astronomical Observatory Chinese Academy of Sciences Center for space science and Applied Research Chinese Academy of Sciences

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four Chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover