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Monitoring of rice crop using ENVISAT ASAR data

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, {3. 100101, china 2. Graduate University of Chinese Academy of Sciences, {3. 10003., china 3. Department of Geography, University of Maryland, College Park, MD 20742, USA 4. Forest Remote Sensing Lab, Research Institute of Forest Resource and Information Technology, Chinese Academy of For-estry, {3. 100091, china 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.

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Joint source channel VL coding/decoding for deep space communication networks based on a space trellis

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Science china(Information Sciences) 2011年第9期54卷 1883-1894页

作者： WU WeiRen 1,TU Juan 2,TU GuoFang 1,GAO ShaoShuai 1 & ZHANG Can 1,3.1 School of Information Science and Engineering,Graduate University of Chinese Academy of Sciences,beijing 100049,china 2 beijing Institute of Electronic System Engineering,china Aerospace Science & Industry Corp.,beijing 100854,china 3.state key laboratory of Information Security,Graduate University of Chinese Academy of Science,beijing 100049,china School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing China beijing Institute of Electronic System Engineering China Aerospace Science & Industry Corp. Beijing China state key laboratory of Information Security Graduate University of Chinese Academy of Science Beijing China

This paper presents joint source channel variable length (VL) coding/decoding based on a space *** constructing a joint decoding plane trellis,better decoding performance can be achieved than by using the bit-level decoding ***,the plane trellis is complicated,which results in high decoding complexity for decoding VL turbo *** solve this problem,we construct a space trellis and design a low-complexity joint decoding algorithm with a variable length symbol-a posteriori probability (VLS-APP) algorithm in resource constrained deep space communication *** results show that the proposed approach reduces the decoding complexity by 10% compared with the plane trellis,and the gain of Eb/N0 is about 0.2 dB at SER=***,it provides substantial error protection for variable-length encoded image data.

关键词： joint coding/decoding VL turbo codes space trellis VLS-APP

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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

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

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Bioinformatics analyses for signal transduction networks

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Science china(Life Sciences) 2008年第11期51卷 994-1002页

作者： LIU Wei1,2, LI Dong2, ZHU YunPing2 & HE FuChu1,2 1 College of Mechanical & Electronic Engineering and Automatization, National University of Defense Technology, Changsha 410073. china 2 state key {3. of Proteomics, {3. Proteome Research Center, {3. Institute of Radiation Medicine, {3. 102206, china College of Mechanical & Electronic Engineering and Automatization National University of Defense Technology Changsha China state key laboratory of Proteomics Beijing Proteome Research Center Beijing Institute of Radiation Medicine Beijing China

Research in signaling networks contributes to a deeper understanding of organism living activities. With the development of experimental methods in the signal transduction field, more and more mechanisms of signaling pathways have been discovered. This paper introduces such popular bioin-formatics analysis methods for signaling networks as the common mechanism of signaling pathways and database resource on the Internet, summerizes the methods of analyzing the structural properties of networks, including structural Motif finding and automated pathways generation, and discusses the modeling and simulation of signaling networks in detail, as well as the research situation and tendency in this area. Now the investigation of signal transduction is developing from small-scale experiments to large-scale network analysis, and dynamic simulation of networks is closer to the real system. With the investigation going deeper than ever, the bioinformatics analysis of signal transduction would have immense space for development and application.

关键词： signal transduction structural motif automated pathways regeneration dynamics simulation

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Insights into correlation between satellite infrared information and fault activities

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Progress in Natural Science:Materials International 2006年第4期16卷 394-402页

作者： MA Jin, WANG Yipeng, CHEN Shunyun, LIU Peixun and LIU Liqiang state key laboratory of Earthquake Dynamics, Institute of Geology,{3. Earthquake Administration, {3. 100029,{3. state key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

Tectonic activities are accompanied with material movement and energy transfer, which definitely change the state of thermal radiation on the ground. Thus it is possible to infer present-day tectonic activities based on variations of the thermal radiation state on the ground. The received satellite infrared information is, however, likely influenced by many kinds of factors. Therefore, the first problem that needs to be solved is to extract information on tectonic activities and eliminate effects of external (non-tectonic) factors. In this study, we firstly make a review of the current studies on this subject, and then present the technical approach and our research goal. Using the data of 20 years from the infrared band of the satellite of National Oceanic and Atmospheric Administration (NOAA) and the method we have developed, we investigate fault activities in western china. The results show that the areas with high residual values of land surface brightness temperature (LSBT), which is presumably related to faultings in{3., accord usually with the locations of followed major earthquakes. The times of their value growing are also roughly consistent with the beginning of active periods of earthquakes. The low frequency component fields of the LSBT, acquired from wavelet analysis, exhibit well the spatial distributions of active faults. The "heat penetrability index" (HPI) related with enhancement of subsurface thermal information has been expressed well for the backgrounds of accelerated tectonic motions, and some correlations exist between HPI and the local faulting and seismicity. This study provides a new approach to study temporal-spatial evolution of recent activities of faults and their interactions.

关键词： infrared emission fault activity residual of land surface brightness temperature heat penetrability index.

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Environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2 1 state key laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,{3. 100093. china 2 School of Geographic and Oceanographic Sciences,Nanjing University,Nanjing 210093.china state key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

Environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 3. kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science china Earth Sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2, WANG Gangsheng1, TAN Ge1, YE Aizhong2 & G. H. Huang3.1. key laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101,{3. 2. {3. key laboratory of Water Resources & Hydropower Engineering Sciences, Wuhan University, Wuhan 43.072,{3. 3. Faculty of Engineering, University of Regina, 3.3. Wascana Parkway, Regina, Sask., S4S 0A2, Canada Correspondence should be addressed to Xia Jun key laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China state key laboratory of Water Resources & Hydropower Engineering Sciences Wuhan University Wuhan China Faculty of Engineering University of Regina Sask Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern china and the Chaobai River basin located in the semihumid region of northern china. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

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Heat flow distribution in Chinese continent and its adjacent areas

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Progress in Natural Science:Materials International 2008年第7期18卷 843-849页

作者： Wei Tao a,*, Zhengkang Shena,b a state key laboratory of Earthquake Dynamics, Institute of Geology,{3. Earthquake Administration, {3. 100029,{3. b Department of Earth and space Sciences, University of California, Los Angeles, CA 90095-1567, USA state key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China Department of Earth and space Sciences University of California Los Angeles CA 90095-1567 USA

Using a compilation of 6980 heat flow measurements, we produce a new heat flow map for the Chinese continent and its adjacent areas. We develop an objective and integrated method to interpolate the heat flow data, taking into account both the uniformity within geological units and coherency of regional heat flow. The geologic units are outlined based on Zhang et al.’s active tectonic block model. Our heat flow model is presented in two formats: a contour map and a heat flow dataset with values on a 1×1° grid for the Chinese continent and its adjacent areas, reflecting detailed variations in some regions. Also provided is a resolution map which helps understand the reliability of the heat flow model. Our results reveal that (1) Heat flows in the eastern part of the Chinese continent are relatively higher than those in the western part except that in the Tibetan Plateau area. (2) Heat flows in the Ordos and North china blocks are around 60 mW/m2, and are 50–55 mW/m2 in South china except for the continental marginal sea regions. (3. Heat flow is the lowest in the Junggar Basin, only 3.–45 mW/m2, and is 45–55 mW/m2 in the Tarim Basin. The results of this study provide an important data- set for studies on thermal and rheological structures of the Chinese continent and its adjacent areas.

关键词： Heat flow Chinese continent and its adjacent areas Geological units Contour map Resolution map

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Synthesis and Crystal Structure of [Cis-1,10phenanthroline-palladium(Ⅱ)(THF)_2]dinitrate (THF = Tetrahydrofuran)

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Chinese Journal of Structural Chemistry 2003年第5期22卷 547-549页

作者： HUANG Hui YU Shu-Yan② (state key laboratory of Polymer Physics and Chemistry, Joint laboratory of Polymer Science and Materials, Institute of Chemistry, The Chinese Academy of Sciences, {3. 100080, china) Institute of Chemistry The Chinese Academy of Sciences State Key Laborator6y of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials CAS 北京 100080

A mononuclear complex, cis-1,10-phenanthroline-palladium(Ⅱ)(THF)2]dinitrate (THF = tetrahydrofuran) [Pd(C10H8N2)(C4H8O)2](NO3.2 1, has been prepared and structurally characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c with a = 7.881(1), b = 27.3.1(3., c = 10.178(1) ? ?= 103.3.3.3.? V = 213..5(4) 3. Mr = 554.83. Dc = 1.725 g/cm3. Z = 4, F(000) = 1128 and (MoK) = 0.926 mm-1. The structure was refined to R = 0.0678 and wR = 0.1651 for 1687 observed reflections with I > 2(I). It is revealed that the central Pd(Ⅱ) ion in the title complex is bonded to two THF and two phenanthroline molecules in a cis-configuration to form the coordination geometry, deviating slightly from the square plane.

关键词： crystal structure Pd(Ⅱ) complex 1,10-phenanthroline

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Quantitative analysis of soil pores under natural vegetation successions on the Loess Plateau

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Science china Earth Sciences 2010年第4期53卷 617-625页

作者： ZHAO ShiWei1,ZHAO YongGang1,2 & WU JinShui3.1 state key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest Agriculture & Forestry University,Yangling 712100,{3. 2 Graduate University of Chinese Academy of Sciences,beijing 100049,{3. 3.Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,{3. state key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Northwest Agriculture & Forestry University Yangling China Graduate University of Chinese Academy of Sciences Beijing China Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha China

Soil pore is a key attribute of the soil structure that affects soil reservoir under natural vegetation recovery on the Loess *** study is to quantitatively analyze soil pore parameters,measured with Computed Tomography(CT) at 15-57 mm depths under five different vegetation succession stages using a concept of substituting "space" for "time" in the Ziwuling Forest Region of the Loess *** results showed that the soil pore parameters,such as pore number,porosity,circularity,and fractal dimension,increased significantly under the natural vegetation successions and varied with the pattern climax community stage>pioneering arbor community stage>scrub community stage>herbaceous community stage>abandoned farmland stage,indicating that natural vegetation recovery could remarkably improve soil pore *** the vegetation succession,this positive effect will be strengthened gradually,which means that the soil pore parameters may appear to be best at the climax community *** organic matter content increased linearly with the soil pore parameters(P<0.001).Increased organic matter accumulation was one of the major reasons for the changes in soil pore characteristics in natural vegetation succession.

关键词： Computed Tomography Loess Plateau natural vegetation succession soil pore soil organic matter

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