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Progress in Natural science:Materials International 2004年第3期 95-96页

作者： ZHAO Hongrui* and WANG Jindi(Research Center for remote sensing and GIS, Department of Geography, beijing Normal University, beijing {4. laboratory for remote sensing of Environment and Digital Cities, beijing 100875, china) ResearchCenterforremotesensingandGIS DepartmentofGeographyBeijingNormalUniversityBeijingKeyLaboratoryforRemoteSensingofEnvironmentandDigitalCitiesBeijing100875China

Reciprocity principle is a common theory in electromagnetics and optics. It is also one of the general principles of the radiation transformation theory. However, in many remote sensing studies, this principle cannot be always supported by experimental data, especially when the scaling effect of the remote sensing image pixel is considered. The debate over the issue of whether the reciprocity principle can be used as a fundamental standard in evaluating the effectiveness of remote sensing observations has lasted for years. Using geometrical optics model, Li and Wan proved the existence of the scaling effect in applying the reciprocity principle to a remote sensing image pixel in 1998. In 2002, Snyder challenged Li’s proof, and attempted to prove that reciprocity principle is universally valid without any scale limitation. In this paper, we will argue with Snyder’s theory and point out that Snyder’s theory had neglected an important condition used in Li’s proof and, as a result, drawn the wrong conclusion. Here we will restate Li’s condition in his demonstration and offer a further proof to verify that reciprocity principle cannot be applied unconditionally to the study of bi directional reflectance distribution function (BRDF) of land surfaces in field or satellite remote sensing observation scale.

关键词： BRDF reciprocity scaling effect.

Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

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science china Earth sciences 2006年第6期49卷 632-640页

作者： QIN Jun1, YAN Guangjian1, LIU Shaomin1, LIANG Shunlin2, ZHANG Hao1, WANG Jindi1 & LI Xiaowen1 1. State key laboratory of remote sensing {4., School of Geography and remote sensing, Research Center for RS&GIS, beijing Normal University, beijing 100875, china 2. Department of Geography, 2181 Lefrak Hall, University of Maryland, College Park, MD2074., USA 1. State key laboratory of remote sensing {4. School of Geography and Remote Sensing Research Center for RS&GIS Beijing Normal University Beijing 100875 China 2. Department of Geography 2181 Lefrak Hall University of Maryland College Park MD20742 USA

The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion.

关键词： remote sensing inversion, a priori knowledge, posterior distribution, ensemble kalman filter, BRDF, kernel-driven model, albedo.

A new approach toward object-based change detection

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science china(Technological sciences) 2010年第S1期53卷 105-110页

作者： ZHANG Guo1,2,LI Yang1 & LI ZhiJiang3 1 State key laboratory of Information Engineering in Surveying,Mapping and remote sensing,Wuhan University,Wuhan 4.0079,{4. 2 Satellite of Surveying and Mapping Application center,State Bureau of Surveying and Mapping,beijing 100830,{4. 3 School of Printing and Packaging,Wuhan University,Wuhan 4.0079,{4. Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China State Bur Surveying & Mapping Satellite Surveying & Mapping Applicat Ctr Beijing 100830 Peoples R China Wuhan Univ Sch Printing & Packaging Wuhan 430079 Peoples R China

Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is *** two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding *** change detection is implemented based on the integration of corresponding objects’ intensity and texture *** are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and *** color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral *** verification work is carried out to show the accuracy of the proposed approach.

关键词： mean shift united segmentation change detection object-based intensity texture integration

Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3 & PENG Jian4.1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2 national Satellite Meteorological Center, china Meteorological Administration, beijing 100081, china 3 institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 4.School of Environmental sciences, Peking University, beijing 100871, china 1. School of Water Resource and Hydropower Sichuan University Chengdu 610065 China 2. national Statellite Meteorological Center China Meteorological Administration Beijing 100081 China 3. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 4. School of Environmental sciences Peking University Beijing 100871 China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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science china Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2,3,HUANG JiKun 1,3 & DENG XiangZheng 1,3 1 institute of Geographic sciences and Natural Resources Research,chinese academy of sciences,beijing 100101,china 2 Department of Economics and Management,Zhejiang Forestry University,Linan 311300,china 3 Center for chinese Agricultural Policy,chinese academy of sciences,beijing 100101,china 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote {4. data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

Spatial heterogeneity of the driving forces of cropland change in china

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science china Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2,3 1. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 3. College of Arts and sciences of beijing Union University, beijing 100083, china 4. School of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL3684., USA 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China 3. School of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

Multi-channel SAR imaging based on distributed compressive sensing

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science china(Information sciences) 2012年第2期55卷 245-259页

作者： LIN YueGuan1,2,3,ZHANG BingChen1,2,JIANG Hai1,2,3,HONG Wen1,2 & WU YiRong1,2 1national key laboratory of science and Technology on Microwave Imaging,{4. 100190,china 2institute of Electronics,chinese academy of sciences,{4. 100190,china 3Graduate University of chinese academy of sciences,{4. 10004.,china 1. national key laboratory of science and Technology on Microwave Imaging Beijing 100190 China2. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

The rapid development of compressive sensing(CS)shows that it is possible to recover a sparse signal from very limited *** aperture radar(SAR)imaging based on CS can reconstruct the target scene with a reduced number of collected samples by solving an optimization *** multi-channel SAR imaging based on CS,each channel requires sufficient samples for separate imaging and the total number of samples could still be *** propose an imaging algorithm based on distributed compressive sensing(DCS)that reconstructs scenes jointly under multiple ***-channel SAR imaging based on DCS not only exploits the sparsity of the target scene,but also exploits the correlation among *** requires significantly fewer samples than multi-channel SAR imaging based on *** multiple channels offer different sampling rates,DCS joint processing can reconstruct target scenes with a much more flexible allocation of the number of measurements offered by each channel than that used in separate CS processing.

关键词： synthetic aperture radar multi-channel synthetic aperture radar compressive sensing distributed compressive sensing

Study of attenuation depths for MODIS bands in the Bohai Sea in china

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Acta Oceanologica Sinica 2009年第5期28卷 39-48页

作者： LIU Ying LI Guosheng institute of Geographic sciences and Natural Resources Research Chinese Academy of Science Beijing 100101 China Xinjiang institute of Ecology and Geogrphy Chinese Academy of Science Urumqi 830011 China

An attenuation depth is defined for remote sensing purposes as a depth above which 90% of the arising light leaving the water surface is originated. The deeper the attenuation depth, the more information of water is detectable by remote sensing, then the more precise information of water is extracted. Meanwhile, the attenuation depth is helpful to know water layer （by its thickness） from which remote sensing will be able to extract information. A number of investigators are using the moderate resolution imaging spectroradiometer （or MODIS） for remote sensing of ocean color. It is necessary to have a rough idea of the effective attenuation depth of imagery in each of the spectral bands employed by the MODIS. The attenuation depth is directly determined from MODIS data. Though analyzing the spectral distribution of the attenuation depth on 7 August 2003 and the seasonal variation of the attenuation depth （551 nm） in the Bohai Sea indicated that： the spectral distribution of the attenuation depth for the spectral range between 4.0 to 700 nm is single-peak curve, and it’s similar and difference in different regions is consistent with other scholars’ results of zoning, moreover, it supports the Bohai Sea is Case 2 water; the maximum attenuation depth shifts toward longer wavelengths, liking the red shift, with increase of turbidity of water, just like the maximum attenuation depth in the outside of the northwest coast of the Bohai Sea and the Bohai Strait is at 531nm, in the central of the Bohai Sea is at 551nm, in the region controlled by the Huanghe （Yellow） River, the region impacted by the old Huanghe River, the western side of the Liaodong Bay and the eastern side of the Liaodong Bay is at 555 nm; the seasonal change of the attenuation depth is the largest in the summer, followed by the fall, and the ranking of winter and spring in different regions is distinct. The attenuation depth in different regions is dissimilar： the order of the attenuation depth in different

关键词： attenuation depth MODIS Bohai Sea

Efficient visualization techniques for high resolution remotely sensed data in a network environment

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science china(Technological sciences) 2008年第S1期51卷 124-134页

作者： WENG JingNong1,WU Lun2,HUANG Jian1,XIA YuBin3 & CAI Heng1 1 College of Software,Beihang University,beijing 100083,china 2 institute of Geographical Information System and remote {4.,Peking University,beijing 100871,china 3 College of Computer,Beihang University,beijing 100083,china 1. College of Software Beihang University Beijing 100083 China2. Institute of Geographical Information System and Remote Sensing Peking University Beijing 100871 China3. College of Computer Beihang University Beijing 100083 China

There are three major research hotspots in efficient visualization techniques of high resolution remotely sensed data in network environment: the data organiza-tion and access in disk storage,the image data stitching and fitting methods,and the network transfers and access. In this paper a new method of "Big File" organi-zation for improving the storage access efficiency of high resolution remote data is presented; a "virtual data source" concept is introduced to solve the stitching problem of remotely sensed data from different sources with different resolutions; a remotely sensed data access engine design based on ATL technique is discussed to process the network transfers and access of remotely sensed data. All these techniques have been adopted in a prototype of digital china named "chinaStar".

关键词： high resolution remotely sensed data spatial index pyramid model LOD Big File