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A hybrid matching method for geospatial services in a composition-oriented environment

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Science china(Technological sciences) 2010年第S1期53卷 213-220页

作者： LUO An 1,2.WANG YanDong 1,2.& CHEN ShengHua 2.1 state {4. {2. of Software Engineering,Wuhan University,Wuhan 4.0072.china 2.state {4. {2. of Information Engineering in Surveying,Mapping and remote sensing,Wuhan University,Wuhan 4.0079,china 1. state key {2. of Software Engineering Wuhan University Wuhan 430072 China 2. state key {2. of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

With the development of Internet and GIS,large volumes of spatial data,powerful computing resources and many spatial data processing functions are published in the form of Web *** suitable geospatial services in the composition-oriented environment is a crucial *** semantic Web provides a kind of technology to find and compose various service resources automatically through the *** paper proposes a hybrid method for the semantic matching of geospatial *** method includes two *** 1 puts forward a multi-level semantic matching approach,which matches single geospatial service at four levels:classification,input/output,precondition/effect and the quality of service(QoS).This multi-level matching approach makes single service matching quicker and more *** 2.puts forward a matching algorithm for a geospatial service chain based on the *** algorithm adopts a trace algorithm,taking account of the effect of the *** restricts the input/output parameters of the current service by the input/output parameters of service chain,pre-service and *** matches the atomic service dynamically in a composition-oriented environment,and accurately converts the abstract model of geospatial services into an executable geospatial service chain.A case study of the flood analysis for the Poyang Lake illustrates the effectiveness of our context-based matching method for geospatial services.

关键词： geospatial services semantic context composition service match

A suspended sediment satellite sensing algorithm based on gradient transiting from water-leaving to satellite-detected reflectance spectrum

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chinese Science Bulletin 2000年第10期45卷 925-931页

作者： LI Yan & LI Jing1. Second institute of Oceanography, state Oceanic Administration, Hangzhou 310012.{2. 2. institute of remote sensing Technology and Application, Peking University, beijing 100871,{2. Second institute of Oceanography State Oceanic Administration Hangzhou China institute of remote {2. Technology and Application Peking University Beijing China

In order to remove the fluctuating atmospheric effects from the Case 2.water, an algorithm for retrieval of suspended sediment concentration from NOAA weather satellite imagery was developed under a new approach. This model is based on the linear response from water-leaving to satellite-detected reflectance spectra, simply reflected by the gradient for correlation curve between reflectance of the advanced very high resolution radiometer (AVHRR) channels 1 (R1, 580-680 nm) and 2.(R2. 72.-1 100 nm). Proportional factor for this gradient transiting, mathematically represented as (td2.td1) (toz2.toz1), depends on a ratio of atmospheric transmittance for such two channels, including ozone and diffuse transmittance. As a simple but efficient algorithm of gradient, the algorithm of αR1-R2.is selected to retrieve gradient a and then sea surface suspendend sediment concentration.

关键词： marine remote sensing suspended sediment atmospheric effect removal gradient transit AVHRR.

Spatial prediction and analysis of Himalayan marmot plague natural epidemic foci in china based on HJ-1 satellite data

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Science china Earth sciences 2010年第S1期53卷 8-15页

作者： GAO MengXu1,4.LI XiaoWen1,2.CAO ChunXiang1,ZHANG Hao1,LI Qun3,ZHOU Hang3 HE QiSheng1,4.XU Min1,4.ZHAO Jian1,4.ZHENG Sheng1,4.& CHEN Wei1,4.1state key {2. of {4. sensing Science,Jointly Sponsored by the institute of remote sensing applications of chinese academy of sciences and beijing Normal University,beijing 100101,china 2.chool of Geography,beijing Normal University,beijing 100875,china 3Office for Disease Control and Emergency Response,chinese Center for Disease Control and Prevention,beijing 102.06,china 4.raduate University of chinese academy of sciences,beijing 10004.,china 1. state key {2. of remote {4. Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Geography Beijing Normal University Beijing 100875 China3. Office for Disease Control and Emergency Response Chinese Center for Disease Control and Prevention Beijing 102206 China

Plague,caused by the gram-negative bacterium Yersinia pestis,is a serious and rapidly progressing illness in humans that can be fatal if not treated *** Qinghai-Tibet Plateau is the largest area of natural Himalayan marmot(Marmota himalayana) plague foci in china and covers more than 630000 *** County in Gansu Province is a part of this natural focus of plague and was chosen as a study *** study used an ecological niche modeling(ENM) approach to predict the potential distribution of the Himalayan *** and Disaster Monitor Satellite(HJ-1) data was used to investigate environment factors that affect plague host animal *** animal point data from active surveillance was combined with environmental variables from the HJ-1 satellite and other databases,and the models of the potential distribution of Himalayan marmot were produced with the Genetic Algorithm for Rule-Set Production(GARP).The probability of marmot presence was divided into 0-5%,5%-2.%,2.%-4.%,4.%-80%,and 80%-100% *** with 80%-100% probability exhibited the greatest potential for the presence of Himalayan *** to the predicted potential distribution of Himalayan marmot in the study area,active surveillance of plague hosts and plague control and prevention could be more efficient.

关键词： Himalayan marmot plague spatial prediction GARP HJ-1 satellite

Image City sharing platform and its typical applications

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Science china(Information sciences) 2011年第8期54卷 1738-1746页

作者： SHAO ZhenFeng & Li DeRen state key {2. for Information Engineering in Surveying,Mapping and remote {4.,Wuhan University,Wuhan 4.0079,china 1. state key {2. for Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

In this paper,the trend of urban spatial information sharing service from the electronic map to image is analyzed and its sharing framework based on service-oriented architecture is ***,the service implementation,feedback data service procedure and its processing service model are explored. Based on the software with independent intellectual property rights,image city of Taizhou is developed as an example to realize various image data and processing servicesLastly,the bright future prospects of image city are described.

关键词： Image City service-oriented architecture image data service function service model service

An efficient rendering method for large vector data on large terrain models

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Science china(Information sciences) 2010年第6期53卷 1122-1129页

作者： YANG Ling1,ZHANG LiQiang1,KANG ZhiZhong2.XIAO ZhiQiang1,PENG JunHuan2.ZHANG XingMing1 & LIU Liu11state key {2. of remote sensing Science,Jointly Sponsored by beijing Normal University and the institute of remote sensing applications of chinese academy of sciences,beijing 100875,china 2.epartment of Geodesy and Geomatics,School of Land Science and Technology,china University of Geo{14.,beijing 100083,china 1. state key {2. of remote {4. Science Jointly Sponsored by Beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences Beijing 100875 China2. Department of Geodesy and Geomatics School of Land Science and Technology China University of Geosciences Beijing 100083 China

This paper presents an efficient way to render large-scale vector maps on level-of-detail(LOD) digital elevation models(DEMs).By using the frame buffer and Voronoi diagram,we achieve a rapid simplification of large-scale vector maps while keeping their original topological *** the simplified maps,we establish level-of-detail vector map *** the detailed level,we use the stencil shadow volume approach to render the map accurately,and in the coarse level we use substitute techniques to render the map approximately yet more *** method proposed in this paper is universally applicable to rendering vector maps on various LOD terrain models,and the overlaying performance is independent of the complexity of underlying terrain *** use of the view frustum culling and sub-region index techniques,the impact of complexity of vector maps is reduced,and the rendering time is restricted to a certain ***,we can achieve seamless and rapid rendering of large-scale vector maps on LOD terrain surfaces.

关键词： large-scale vector maps LODs view-dependent visualization

Water target based cross-calibration of CBERS-02.CCD camera with MODIS data

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Science china(Technological sciences) 2005年第S2期48卷 61-71页

作者： TANG Junwu1,2. GU Xingfa2. NIU Shengli1, MA Chaofei1 & MIN Xiangjun3 1. National Satellite Ocean Application Service (NSOAS), beijing 100081, china 2. {2. key laboratory of remote sensing Science, beijing 100010, china 3. china Center for Resource Satellite Data and applications (CRESDA), beijing 100083, china 1. National Satellite Ocean Application Service (NSOAS) 100081 Beijing China 2. state key {2. of {4. sensing Science 100010 Beijing China 3. china Center for Resource Satellite Data and applications (CRESDA) 100083 Beijing China

In order to make quantitative watercolor sensing with china-Brazil Earth Resources Satellite (CBERS-02. CCD camera, the MODIS data with higher accuracy is used to cross-calibrate the CCD camera over water targets. In homogeneous clear water area, two pairs of images obtained over the same area on the same day by the two sensors are selected. The top-of-atmosphere (TOA) radiances of the multispectral bands of CCD are calculated with the water and aerosol parameters from MODIS based on a water-atmosphere radiative transfer algorithm. The stripes in CCD image that caused by unequal response of the CCD array detectors are firstly removed before making the cross-calibration. The same part of CCD detectors is selected for the calibrations in the two images to eliminate the residual error of destriping and uniformity correction for the focus plane irradiance. It is shown that the calibration results from two different images are consistent. The error of this method is about 5%.

关键词： CBERS-02 CCD MODIS radiometric calibration cross-calibration. DOI: 10.1360/05ze1006

Quantitative estimation of the shrub canopy LAI from atmosphere-corrected HJ-1 CCD data in Mu Us Sandland

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Science china Earth sciences 2010年第S1期53卷 26-33页

作者： CHEN Wei1,2,CAO ChunXiang1,HE QiSheng1,2,GUO HuaDong3,ZHANG Hao1,2,LI RenQiang4.ZHENG Sheng1,2,XU Min1,2,GAO MengXu1,2,ZHAO Jian1,2,LI Sha1,NI XiLiang1,2,JIA HuiCong1,JI Wei1,TIAN Rong1,2,LIU Cheng1,2,ZHAO YuXing5 & LI JingLu6 1 state key laboratory of remote {4. Science,Jointly Sponsored by the institute of remote sensing applications of chinese academy of sciences and beijing Normal University,beijing 100101,china 2 Graduate University of chinese academy of sciences,beijing 10004.,china 3 Center for Earth Observation and Digital Earth,chinese {14. of sciences,beijing 100190,china 4.18} key laboratory of Ecological Network Observation and Modeling,institute of Geographical sciences and Natural Resources Research,chinese {14. of sciences,beijing 100101,china 5 Ordos Forestry Sand Control Science institute,Dongsheng 017000,china 6 Inner Mongolia Biomass Thermoelectricity Limited Company,Wushen 017300,china 1. state key {2. of remote {4. Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate University of chinese academy of sciences Beijing 100049 China 3. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China 4. china key {2. of Ecological Network Observation and Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 5. Ordos Forestry Sand Control Science institute Dongsheng 017000 China 6. Inner Mongolia Biomass Thermoelectricity Limited Company Wushen 017300 China

The leaf area index(LAI) is an important ecological parameter that characterizes the interface between vegetation canopy and the *** addition,it is used by most process-oriented ecosystem *** paper investigates the potential of HJ-1 CCD data combined with linear spectral unmixing and an inverted geometric-optical model for the retrieval of the shrub LAI in Wushen Banner of Inner Mongolia in the Mu Us ***(Moderate Resolution Atmospheric Radiance and Transmittance Model) was used for atmospheric *** was extracted using the threshold of the normalized difference vegetation index,with which water bodies and farmland were separated,in combination with a vegetation map of the People's Republic of china(1:1000000).Using the geometric-optical model,we derive the per-pixel reflectance as a simple linear combination of two components,namely sunlit background and *** fraction of sunlit background is related to the shrub *** the support of HJ-1 CCD data,we employ linear spectral unmixing to obtain the fraction of sunlit background in an atmospherically corrected HJ *** addition,we use the measured shrub canopy structural parameters for shrub communities to invert the geometric-optical model and retrieve the pixel-based shrub *** total,18 sample plots collected in Wushen Banner of Inner Mongolia are used for *** results of the shrub LAI show good agreement with R2.of 0.817 and a root-mean-squared error of 0.173.

关键词： shrub leaf area index inversion HJ-1 data geometric-optical model MODTRAN Mu Us Sandland

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science china(Technological sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2.3, LI Xiaoying1,2.4. MIN Xiangjun5, YU Tao1,2. SUN Jijuan5, ZENG Yong1,2.4. XU Hua1,2.& GUO Ding2.6 1. state key {2. of remote sensing Science, Jointly Sponsored by the institute of remote sensing applications of chinese academy of sciences and beijing Normal University, beijing 100101, china 2. The Center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 4. Graduate University of chinese academy of sciences, beijing 100039, china 5. china Center for Resource Satellite Data and Application, beijing 100830, china 6. University of Electronic Science and Technology of china, Chengdu 610054. china state key {2. of remote {4. Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China The Center for National Spaceborne Demonstration 100101 Beijing China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France Graduate University of chinese academy of sciences 100039 Beijing China china Center for Resource Satellite Data and Application 100830 Beijing China University of Electronic Science and Technology of china 610054 Chengdu China

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 4.° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 4.° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

A method for blind separation of components information from mixed pixel

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Progress in Natural Science:Materials International 2006年第07期16卷 760-765页

作者： FAN Wenjie and XU Xiru ( institute of remote {2. and Geographical Information System, Peking University, beijing 100871,{4. Center of remote {2. and GIS of beijing Normal University, beijing 100875,{4.) [a]institute of remote {2. and Geographical Information System Peking University Beijing China [b]Center of remote sensing and GIS of {2. Nornal University Beijing China

In the field of remote sensing, it is important to separate the component information from mixed pixel. If the physical process of remote sensing can be expressed by a set of linear equations, the remote sensing information matrix is equal to the weight matrix multiplied by the component information matrix. Generally speaking, the precondition of retrieval of component information matrix is that the weight matrix is known. However, the blind signal separation (BSS) method can separate the matrix unconditionally, whose basic principle is that the additive information needing separation can be achieved from the statistical characteristics contained in a mass of samples in the remotely sensed information matrix. Therefore, the values of the component information matrix and the weight matrix can be estimated. The wave shape of components can be retrieved by BSS, but the amplitude cannot. In this paper, the plant-soil mixed pixels were chosen as the studying targets in this paper to quantitatively separate the component information and solve the uncertainty of BSS. Simulation and field test verify the reliability of the method. Results show that the BSS can be one of the effective methods of mixed pixel separation, and the foreground of application is very promising.

关键词： mixed pixel component information blind signal separation.