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Study of thin cloud removal method for CBERS-02.image

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Science china(Technological sciences) 2005年第S2期48卷 91-99页

作者： MA Jianwen1, GU Xingfa1, FENG Chun2.& GUO Jianning2.1. institute of Remote Sensing Application, chinese Academy of {2., beijing 100101, china 2. china Center for Resource Satellite Data and Applications, beijing 100073, china 1. institute of Remote Sensing Application Chinese Academy of Sciences 100101 Beijing China 2. china Center for Resource Satellite Data and Applications 100073 Beijing China

The china Brazil Earth Resources Satellite (CBERS) ended the dependence on foreign satellites. Along with the series of CBERS and the enhancement of satellite applications, it is necessary to search correlative data processing methods. Because cloud appears in the atmosphere, an image with clear sky conditions is often hard to obtain. How to remove cloud is an important sector of increasing image quality. An improved homomorphism filtering method is adopted to remove thin cloud qualitatively at first, and all bands are selected to classify pixels. Based on the fact that visible band images contain more aerosol effects than infrared bands, visible bands are used to determine clear or hazy regions and the reflectances of different surface classes in clear regions are calculated. At last the mean reflectance of the same classes in clear and hazy regions is matched to remove cloud. The image visual effect is improved; meanwhile, the ground reflectance is retrieved to meet the needs of remote sensing quantification.

关键词： CBERS-02 cloud removal surface reflectance mean reflectance matching.

Two-dimensional Riemann problems of simplified Euler equation

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chinese Science Bulletin 1998年第6期43卷 441-444页

作者： YANG Xiaozhou 1,2.and HUANG Feimin+1 1. institute of Applied Mathematics, chinese Academy of {2., beijing 100080, china 2. Department of Mathematics, Shantou University, Guangdong 515063, china institute of Applied Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Shantou University Guangdong China

The two-dimensional Riemann problem of simplifed Euler equation is discussed, in which initial value contains two different constant states that are separated by a smooth curve. This problem is a natural description of realistic phenomena, but it is hard to study by conventional idea. So a new approach is proposed. Some new properties about two-dimensional rarefaction wave, shock wave and intermediate state of solutions are disclosed.

关键词： D Riemann problem implicit functions cylindrical surface pencil of cylindrical surface.

A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,china

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chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. institute of Vertebrate Paleontology and Paleoanthropology, chinese Academy of {2., beijing 100044, china 2. College of Earth {2. and Resources, china University of Geo-{2., beijing 100083, china institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China College of Earth sciences and Resources China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

δD values of escaped H_2.from hot springs at the Tengchong Rehai geothermal area and its origin

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chinese Science Bulletin 2002年第2期47卷 146-149页

作者： SHANGGUAN Zhiguan & HUO Weiguo institute of geology,{2. Seismological Bureau, beijing 10002.,{2. institute of geology and geophysics, chinese Academy of sciences, beijing 10002.,{2. institute of geology China Seismological Bureau Beijing 100029 China

Here we give the δD values of escaped H2.from hot springs at the Tengchong Rehai and adjacent regions, and deal with a genetic correlation between the increment H2.in escaped gases from middle-shallow reservoirs and the H2., CH4 derived from deep sources. Isotopic compositions of H2.indicate that the generation of increment H2.may be related to recent strong activity of N-W trending fault at the Rehai area. Trace monitoring the H2.release could be significant in order to keep watch on present activity of that fault.

关键词： Rehai geothermal area hydrogen stable isotopic composition.

Genesis of excess argon in phengite and significance of ^(40)Ar-^(39)Ar age spectra for omphacite:A case study on UHP eclogite of South Dabie Terrain,china

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chinese Science Bulletin 2000年第15期45卷 1345-1351页

作者： WANG Songshan, GE Ningjie, SANG Haiqing & QIU Ji1. institute of geology and {2., chinese Academy of sciences, beijing 10002., china 2. Department of Earth and Space Science, University of Science and Technology of china, Hefei 2.002., china Correspondence should be addressed to Wang Songshan institute of geology and {2. Chinese Academy of Sciences Beijing China Department of Earth and Space Science University of Science and Technology of China Hefei China

The Ar-Ar dating of phengite and omphacite in ultrahigh-pressure (UHP) eclogite of Bixiling and Hengchong in the South Dabie Terrain shows that the content range of excess argon is as high as (0.4-1.3)×10 8 mol· g 1. The genesis of the excess argon is discussed. The Ar-Ar age spectra of omphacite could not support the opinion that the UHP metamorphism occurred in Caledon epoch and pre-Caledon epoch.

关键词： South Dabie Terrain ultrahigh-pressure metamorphics phengite omphacite excess argon.

The tectonic setting and geochemical characteristics of metamorphic basement in the southwest of the Yangtze Plate

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chinese Science Bulletin 1999年第S2期44卷 266-268页

作者： ZHANG Hongxiang~1, LIU Congqiang~2. HUANG Zhilong~2.and XU Zhifang~1 1. institute of geophysics, {2. Academy of sciences, beijing 100101, china 2. institute of Geochemistry, {2. Academy of sciences, Guiyang 550002. china institute of geophysics Chinese Academy of Sciences Beijing 100101 China institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE Dahongshan Group (in short DG) and its basement Dibadu Formation (in short DF) in the southeastof the Yangtze Plate are one of the oldest geological units in the Yangtze Plate. It is established in thisnote by means of geochemistry that the system of trench-arc-basin was formed by the subducting at thesouthwestern boundary of the Yangtze Plate in Lower Proterozoic Subera. And the existence of enrichedmantle EMI is argued by the way of trace elements geochemistry. 1 Regional geological setting There is a unit of the typical two-layer structure platform in the southwest of the Yangtze Plate. Themetamorphic basement of this platform is made up of Suberathem Dahongshan Group and SuberathemKunyang Group. Above them, there have covered expansive continental deposits from Mesozoic. The primary rocks of DG are composed of deposited limestone, sandstone and basalts. The basalts represent

关键词： Dahongshan Group(DG) Dibadu Formation(DF) tectonic geochemistry.

Y_CΩ_(2.)are easy terms

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chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2.1. Department of Mathematics, Nanjing University, Nanjing 2.0093, china 2. institute of Software, {2. Academy of sciences, beijing 100080, china Department of Mathematics Nanjing University Nanjing China institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2. is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2. =M is consistent, where Y C is Curry fixed point combinator, Ω 2. ≡ω 2. ω 2. and ω 2. ≡λ***...x (there are 2. occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Climatic and environmental changes over the last millennium recorded in the Malan ice core from the northern Tibetan Plateau

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Science china Earth sciences 2006年第10期49卷 1079-1089页

作者： WANG Ninglian1,2. YAO Tandong2.1, PU Jianchen1, ZHANG Yongliang1 & SUN Weizhen1 1. Key Laboratory of Cryosphere and Environment, Cold and Arid Regions Environmental and Engineering Research institute, chinese Academy of {2., Lanzhou 730000, china 2. institute of Tibetan Plateau Research, chinese Academy of {2., beijing 100085, china 1. Key Laboratory of Cryosphere and Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

In this paper, climatic and environmental changes were reconstructed since 112.A.D. based on the Malan ice core from Hol Xil, the northern Tibetan Plateau. The record of δ 18O in the Malan ice core indicated that the warm-season air temperature variations displayed a general increase trend, the 2.th-century warming was within the range of natural climate variability, and the warmest century was the 17th century while the warmest decade was the 1610s, over the entire study period. The “Medieval Warm Epoch” and “Little Ice Age” were also reflected by the ice core record. The dust ratio in the Malan ice core is a good proxy for dust event frequency. The 870-year record of the dust ratio showed that dust events occurred much frequently in the 19th century. Comparing the variations of δ 18O and the dust ratio, it is found that there was a strong negative correlation between them on the time scales of 101―102.years. By analyses of all the climatic records of ice cores and tree rings from the northern Tibetan Plateau, it was revealed that dust events were more frequent in the cold and dry periods than in the warm and wet periods.

关键词： the Tibetan Plateau, the Malan ice core, climate changes, dust event frequency.

Evaluation of the Interfacial Adhesion between Brittle Coating and Ductile Substrate by Cross-Sectional Indention

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材料热处理学报 2004年第5B期25卷 1187-1190页

作者： SUJian-yu ZHANGKun CHENGuang-nan instituteofMechanics ChineseAcademyofSciencesBeijingChina／／GraduateSchooloftheChineseAcademyofSciencesBeijingChina instituteofMechanics ChineseAcademyofSciencesBeijingChina

The cross-sectional indentation method is extended to evaluate the interfacial adhesion between brittle coating and ductile substrate. The experimental results on electroplated chromium coating/steel substrate show that the interfacial separation occurs due to the edge chipping of brittle coating. The corresponding models are established to elucidate interfacial separation processes. This work further highlights the advantages and potential of this novel indentation method.

关键词：分界面附着刻痕可锻衬底应力涂层铬钢