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Cotton pixel identification with CBERS-02 CCD data based on spectral knowledge

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science china(Technological sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1,2,3, LIU Qinhuo1,3, LIU Qiang1, CHEN Liangfu1, BO Junhua3 & LI Shaokun3 1. state key laboratory of remote sensing science, IRSA, Chinese Academy of sciences, beij.ng 100101, china 2. Graduate University of Chinese Academy of sciences, beij.ng 100049, china 3. The key Oasis Eco-agriculture laboratory of Xinjiang Production and Construction Corps, Shi Hezi 832000, china 1. state key laboratory of remote sensing science IRSA Chinese Academy of Sciences 100101 Beijing China 2. Graduate University of Chinese Academy of sciences 100049 Beijing China 3. The key Oasis Eco-agriculture laboratory of Xinjiang Production and Construction Corps 832000 Shi Hezi China

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02 CCD and took them as the reference spectra for spectra fitting. Then No.143 Regiment of No.8 Agricultural Division of Xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02 CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data

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science china Earth sciences 2010年第S1期53卷 16-25页

作者： GUO ZhiFeng1,CHI Hong1,2 & SUN GuoQing1,3 1state key laboratory of remote sensing science,Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of sciences and beij.ng Normal University,Institute of remote sensing Applications,Chinese Academy of sciences,beij.ng 100101,china 2Graduate University of Chinese Academy of sciences,beij.ng 100049,china 3Department of Geography University of Maryland,College Park,MD 20742,USA 1. state key laboratory of remote sensing science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Geography University of Maryland College Park MD 20742 USA

The ecosystem in northeastern china and the Russian Far East is a hotspot of scientific research into the global carbon *** aboveground biomass(AGB) is an important component in the land surface carbon *** this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern china by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory *** resulted statistical regression models have a R2=0.68 for conifer and R2=0.71 for broadleaf *** models were used to estimate biomass for all GLAS footprints of forest located in the study *** GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2=0.55 and R2=0.52 for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 *** data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2=0.71).About 80% of biomass samples had an error less than 20 t ha-1,and the mean error of all validation samples is 5.74 t *** pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this *** was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estim

关键词： Disaster and Environment Monitoring and Forecast Satellite ICESat GLAS waveform boreal forest forest aboveground biomass multiple linear regression

Improvement of a 3D radar backscattering model using matrix-doubling method

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science china Earth sciences 2010年第7期53卷 1029-1035页

作者： NI WenJian1,2, GUO ZhiFeng1 & SUN GuoQing3 1 state key laboratory of remote sensing science, jointly sponsored by the Institute of remote sensing Applications of Chinese Academy of sciences and beij.ng Normal University, beij.ng 100101, china 2 Graduate University of Chinese Academy of sciences, beij.ng 100049, china 3 Department of Geography, University of Maryland, College Park, MD 27042, USA 1. state key laboratory of remote sensing science jointly sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Geography University of Maryland College Park MD 27042 USA

Radiative transfer models have been widely used to simulate the radar backscattering from forested areas. A three-dimensional radar backscatter model of forest canopy developed in previous studies takes full account of spatial position of trees in a forest stand, and the interactions among crown, trunk and ground surface. The model predicted well for the co-polarized backscatter measurements, but underestimated the backscattering for cross-polarization, primarily because only the first-order scattering within tree crowns was considered in the model. The backscattering at cross-polarization depends strongly on multiple scatter- ing within tree crowns. To produce good estimations for cross-polarized component, the matrix-doubling method is employed here to compute multiple-scattering within the crown. The modified model is compared with the original model, and the field forest measurements and AIRSAR data are used for validation of the modified model. The cross-polarization backscattering is improved in different degrees for different crown structures and at different bands.

关键词： remote sensing forestry electromagnetic propagation radar backscattering model matrix-doubling

Matrix calculation of high-dimensional cross product and its application in automatic recognition of the endmembers of hyperspectral imagary

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science china(Information sciences) 2011年第1期54卷 197-203页

作者： GEng XiuRui1,ZHAO YongChao1,LIU SuHong2 & WAng FuXiang3 1key laboratory of Technology in Geo-spatial Information Processing and Application System, Institute of Electronics,Chinese Academy of sciences,beij.ng 100080,china 2state key laboratory of remote sensing science,Jointly Sponsored by beij.ng Normal University and the Institute of remote sensing Applications of Chinese Academy of sciences, School of Geography,beij.ng Normal University,beij.ng 100875,china 3School of Electronics and Information Engineering,Beihang University,beij.ng 100191,china 1. key laboratory of Technology in Geo-spatial Information Processing and Application System Institute of Electronics Chinese Academy of Sciences Beijing 100080 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by Beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences School of Geography Beijing Normal University Beijing 100875 China3. School of Electronics and Information Engineering Beihang University Beijing 100191 China

This paper gives the definition of the high-dimensional cross product and its calculation by extending the 3-D cross product definition into the high-dimensional vector *** on the properties of the cross product,the volume variance index(VVI)is proposed to be used in extracting automatically the endmembers of the hypherspectral imagery which eliminates the shortcoming of the traditional method of using simplex only where the extraction results were easily impacted by the abnormal pixels.A case study of endmembers extraction experiment using the VVI method with the AVIRIS data for Cuprite has shown a very good result.

关键词： endmember simplex hyperspectral imagery cross product

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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science china Earth sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2 1.Institute of remote sensing and GIS of Peking University,beij.ng 100871,china 2.Center of remote sensing and GIS of beij.ng Normal University,beij.ng 100875,china 1. Institute of remote sensing and GIS of Peking University 100871 Beijing China 2. Center of remote sensing and GIS of beij.ng Normal University 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.

GRACE detection of the medium-to far-field coseismic gravity changes caused by the 2004 Mw9.3 Sumatra-Andaman earthquake

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Earthquake science 2012年第3期25卷 235-240页

作者： Jin Li1,2,3 and Wenbin Shen1,3,4, 1 Department of Geophysics, School of Geodesy and Geomatics, Wuhan University, Wuhan 430079, china 2 key laboratory of Geodynamic Geodesy of Chinese Academy, Wuhan 430077, china 3 key laboratory of Geospace Environment and Geodesy (Ministry of Education), Wuhan University, Wuhan 430079, china 4 state key laboratory of Information Engineering in Surveying, Mapping and remote sensing, Wuhan 430079, china 1. Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan 430079 China 2. key laboratory of Geodynamic Geodesy of Chinese Academy Wuhan 430077 China 3. key laboratory of Geospace Environment and Geodesy (Ministry of Education) Wuhan University Wuhan 430079 China 4. state key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan 430079 China

Large earthquakes cause observable changes in the Earth’s gravity field, which have been detected by the Gravity Recovery and Climate Experiment (GRACE). Since most previous studies focus on the detection of near-field gravity effects, this study provides the results from the medium- to far-field gravity changes caused by the 2004 Sumatra-Andaman earthquake that are recorded within GRACE monthly solutions. Utilizing a spherical-earth dislocation model we documented that large-scale signals predominate in the global field of the coseismic gravity changes caused by the earthquake. After removing the near-field effects, the coseismic gravity changes show a negative anomaly feature with an average magnitude of -0.18×10-8 m·s-2 in the region ranging ～40° from the epicenter, which is considered as the 'medium ffield' in this study. From the GRACE data released by Center for Space Research from August 2002 to December 2008, we retrieved the large-scale gravity changes smoothed with 3 000 km Gaussian ffilter. The results show that the coseismic gravity changes detected by GRACE in the medium field have an average of (-0.20±0.06)×10-8 m·s-2, which agrees with the model prediction. The detection confirms that GRACE is sensitive to large-scale medium-field coseismic gravitational effects of mega earthquakes, and also validates the spherical-earth dislocation model in the medium field from the perspective of satellite gravimetry.

关键词： GRACE medium-to far-field coseismic gravity change 2004 Sumatra-Andaman earthquake spherical-Earth dislocation model

Integrative inversion of land surface component temperature

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science china Earth sciences 2005年第11期48卷 2011-2019页

作者： FAN Wenjie1 & XU Xiru1,2 1. Institute of remote sensing and Geographical Information System, Peking University, beij.ng 100871, china 2. Center of remote sensing and GIS of beij.ng Normal University, beij.ng 100875, china 1. Institute of remote sensing and Geographical Information System Peking University 100871 Beijing China 2. Center of remote sensing and GIS of beij.ng Normal University 100875 Beijing China

In this paper, the row winter wheat was selected as the example to study the com-ponent temperature inversion method of land surface target in detail. The result showed that the structural pattern of row crop can affect the inversion precision of component temperature evi-dently. Choosing appropriate structural pattern of row crop can improve the inversion precision significantly. The iterative method combining inverse matrix was a stable method that was fit for inversing component temperature of land surface target. The result of simulation and field ex-periment showed that the integrative method could remarkably improve the inversion accuracy of the lighted soil surface temperature and the top layer canopy temperature, and enhance inver-sion stability of components temperature. Just two parameters were sufficient for accurate at-mospheric correction of multi-angle and multi-spectral thermal infrared data: atmospheric trans-mittance and the atmospheric upwelling radiance. If the atmospheric parameters and component temperature can be inversed synchronously, the really and truly accurate atmospheric correction can be achieved. The validation using ATSRII data showed that the method was useful.

关键词： components temperature, inverse pattern, atmospheric correction

Research on the Earth system multi-body force system dynamical model

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science china(Technological sciences) 2006年第z2期49卷 11-22页

作者： CHEN Xiaofei, BI Siwen, WU Fei & DOng Qianlin state key laboratory of remote sensing science, Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of sciences and beij.ng Normal University, beij.ng 100101, china laboratory of 3D Information Access and Application of Capital Normal University, beij.ng 100037, china Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beij.ng Normal Univ Beijing 100101 Peoples R China Capital Normal Univ Lab D Informat Access & Applicat 3 Beijing 100037 Peoples R China

This paper presents an overview of the binding force and freedom force of Earth system, and describes force moment to point and line and force system in the Earth system. It introduces the force theory of the Earth system multi-body force system from special or equivalent force system of Earth system mechanics, general force and no-power force of Earth system. Finally it describes the force and moment of nodes of Earth system and provides basic model for the research of the Earth system multi-body dynamics.

关键词： Earth system, multi-body system force, dynamics, basic models.

ON IMPROVEMENT OF BARE SURFACE SOIL MOISTURE ESTIMATION WITH L-BAND DUAL-POLARIZATION RADAR

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ON IMPROVEMENT OF BARE SURFACE SOIL MOISTURE ESTIMATION WITH...