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An improved line-of-sight method for visibility analysis in 3D complex landscapes

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Science china(Information Sciences) 2010年第11期53卷 2185-2194页

作者： LIU Liu1, ZHANG LiQiang1, MA JingTao2. ZHANG Liang3, ZHANG XingMing1, XIAO ZhiQiang1 & YANG Ling1 1State Key Laboratory of remote sensing Science, Jointly Sponsored by{2. and the Institute of remote sensing Applications of Chinese Academy of Sciences, beijing 100875, china 2.TV America, Inc. 1145 Broadway Plaza Ste 605, Tacoma, WA 98407, USA 3School of Geomatics and Urban Information, beijing university of Civil Engineering and Architecture, beijing 100044, china 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 PTV America Inc.

This paper presents an efficient method for implementing visibility analysis on complex landscapes based on an improved LOS (line of sight) algorithm. The method determines the viewshed by analyzing the geometric relationship between the target points and viewpoint. It differentiates the visibility of the target points by the elevation information. Eventually the visual results related to the given viewpoint are rendered on three-dimensional landscapes. The visibility of some target points is computed by comparing their elevations with the viewpoint's height, thus is able to enhance the efficiency of the visibility analysis. This method can not only be applied in the visibility analysis of forest scenes, but also used in the analysis of the urban environment. Experiments show that the proposed method results in high efficiency and precision.

关键词： line of sight visibility analysis complex landscapes visual permeability

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2.3 & BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and Resource Development, Jiangxi normal university, Nanchang 33002.,{2. 2.Institute of Geographic Sciences and Resources research, Chinese Academy of Sciences, beijing 100101,{2. 3 School of geography and Environmental Sciences, Jiangxi normal university, Nanchang 33002.,{2.

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 31, 2.05 was combined with gis thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by {2. sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

An Earth multi-body system elasticity and plasticity dynamics model

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Science china(Technological Sciences) 2006年第Z2期49卷 23-29页

作者： ZHANG Qingxian, BI Siwen & GONG Huili Education Ministry Key Laboratory of Three-Dimensional Information Extraction and Application, Capital normal university, {2. 100037, china State Key Laboratory of remote sensing Science, IRSA, Chinese Academy of Sciences, {2. 100101, china Capital normal Univ Educ Minist Key Lab Dimens Informat Extract & App Beijing 100037 Peoples R China Chinese Acad Sci IRSA State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China

research on the elasticity and plasticity dynamics of the Earth multi-body system, including the Earth multi-body system stratum-block's equivalent inertia force system and generalized inertia force, the Earth multi-body system stratum-block's equivalent inertia force system expressed with partial velocity and partial palstance, and Earth multi-body system generalized inertia force expressed with partial velocity and partial palstance. This research provides a theoretical foundation for further investigation of Earth multi-body dynamics.

关键词： Earth multi-body system, equivalent inertia force system, generalized inertia force, elasticity and plasticity, dynamics model.

A Spectral Index for Estimating Soil Salinity in the Yellow River Delta Region of china Using EO-1 Hyperion Data

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Pedosphere 2010年第3期20卷 378-388页

作者： WENG Yong-Ling GONG Peng ZHU Zhi-Liang department of Surveying and Mapping Engineering College of Transportation Southeast University Nanjing 210096(China) State Key Laboratory of remote sensing Science Institute of Remote Sensing Applications of the Chinese Academy ofSciences and Beijing Normal University Beijing 100101 (China) department of Environment Science Policy and Management University of California Berkeley CA 94720 (USA) EROS Data center U.S. Geological Survey Sioux Falls SD 57198 (USA)

Soil salinization is one of the most common land degradation processes. In this study, spectral measurements of saline soil samples collected from the Yellow River Delta region of china were conducted in laboratory and hyperspectral data were acquired from an EO-1 Hyperion sensor to quantitatively map soil salinity in the region. A soil salinity spectral index (SSI) was constructed from continuum-removed reflectance (CR-reflectance) at 2.52.and 2.03 nm, to analyze the spectral absorption features of the salt-affected soils. There existed a strong correlation (r = 0.91) between the SSI and soil salt content (SSC). Then, a model for estimation of SSC with SSI was established using univariate regression and validation of the model yielded a root mean square error (RMSE) of 0.986 and an R2.of 0.873. The model was applied to a Hyperion reflectance image on a pixel-by-pixel basis and the resulting quantitative salinity map was validated successfully with RMSE = 1.92. and R2.= 0.62.. These suggested that the satellite hyperspectral data had the potential for predicting SSC in a large area.

关键词： hyperspectral reflectance soil salt content spectral absorption features

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 {2.,Wuhan 430079,china 2.Satellite of Surveying and Mapping Application center,State Bureau of Surveying and Mapping,beijing 100830,china 3 School of Printing and Packaging,Wuhan {2.,Wuhan 430079,china State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China Satellite of Surveying and Mapping Application center State Bureau of Surveying and Mapping Beijing China School of Printing and Packaging Wuhan University Wuhan 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

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on remote sensing and {2.

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4 1. The Faculty of geography and Resources Science, Sichuan normal {2., Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, china 3. Graduate {2. of the Chinese Academy of Sciences, beijing 100049, china 4. Information center of Land and Resources department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of geography and Resources Science Sichuan Normal University Chengdu Sichuan China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences Beijing China Information center of Land and Resources department of Sichuan Province Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (gis) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Regional differences and determinants of built-up area expansion in china

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Science china Earth Sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2.ZHU LiFen3,1 & DENG XiangZheng1,2.1 center for Chinese Agricultural Policy,Chinese Academy of Sciences,beijing 100101,{2. 2.Institute of Geographic Sciences and Natural Resources research,Chinese Academy of Sciences,beijing 100101,{2. 3 research center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business university,Chongqing 400067,{2. center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing China Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing China research center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing China

Based on remote sensing data on land use provided by the Chinese Academy of Sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in{2. from the late 1980s to 2.00,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2.00,although{2.'s overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, china

Response of remotely sensed normalized Difference Water Deviation Index to the 2.06 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 {2., 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 School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological center China Meteorological Administration Beijing China Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing China School of Environmental Sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2.06 (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 2.01―2.06 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 2.06 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,{2. 2.department of Economics and Management,Zhejiang Forestry university,Linan 311300,{2. 3 center for Chinese Agricultural Policy,Chinese Academy of Sciences,beijing 100101,{2. Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing China department of Economics and Management Zhejiang Forestry University Linan China center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 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 {2. sensing 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