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On 3D simulation of moving objects in a digital earth system

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Science china(Technological sciences) 2008年第S2期51卷 123-132页

作者： WENG JingNong1,WU Lun2.HUANG Jian1,WANG Yang1,YANG Xue1 & HU Bin1 1 College of Software,Beihang University,beijing 100191,china 2.{2. of Geographical Information System and remote sensing,Peking University,beijing 100871,china College of Software Beihang University Beijing 100191 China institute of Geographical Information System and remote {2. Peking University Beijing 100871 China

"How do the rescue helicopters find out an optimized path to arrive at the site of a disaster as soon as possible?" or "How are the flight procedures over mountains and plateaus simulated?" and so *** this paper a script language on spatial moving objects is presented by abstracting 3D spatial moving objects' behavior when implementing moving objects simulation in 3D digital Earth scene,which is based on a platform of digital china named "chinaStar".The definition of this script language,its morphology and syntax,its compiling and mediate language generating,and the behavior and {2. control of spatial moving objects are discussed *** addition,the language's applications and implementation are also discussed.

关键词： Digital Earth chinaStar moving object script language

Investigation of Image Fusion Between High-Resolution Image and Multi-spectral Image

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Geo-Spatial Information Science 2003年第2期6卷 31-34页

作者： LI Pingxiang WANG ZhijunLI Pingxiang, professor, state key {2. of Information Engineering in Surveying, Mapping and remote {4., Wuhan University, 12. Luoyu Road, Wuhan 4.0079, china. state key {2. of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

On the basis of a thorough understanding of the physical characteristics of remote sensing image, this paper employs the theories of wavelet transform and signal sampling to develop a new image fusion algorithm. The algorithm has been successfully applied to the image fusion of SPOT PAN and TM of Guangdong province,{2.. The experimental results show that a perfect image fusion can be built up by using the image analytical solution and re-construction in the image frequency domain based on the physical characteristics of the image formation. The method has demonstrated that the results of the image fusion do not change spectral characteristics of the original image.

关键词： image fusion remote sensing wavelet transform signal sampling

一种改进的基于小波变换的SAR图像压缩编码

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计算机工程与应用 2004年第16期40卷 91-93页

作者：桑会勇郭华东王长林中国科学院遥感应用研究所遥感信息科学重点实验室北京100101

由于SAR数据图像与光学传感器数据特点有所不同,因此一般的适合光学图像的压缩算法并不一定适合雷达图像。文章根据SAR图像的特点对SPECK算法进行了改进。用此改进方法对SAR图像进行处理,通过与SPIHT算法的比较分析可以看出,该算法从各... 详细信息

由于SAR数据图像与光学传感器数据特点有所不同,因此一般的适合光学图像的压缩算法并不一定适合雷达图像。文章根据SAR图像的特点对SPECK算法进行了改进。用此改进方法对SAR图像进行处理,通过与SPIHT算法的比较分析可以看出,该算法从各个方面都明显优于传统的SPIHT算法,而且这种方法有较好的视觉特征,有利于进行图像的校准和目视解译。

关键词：小波变换嵌入式编码图像压缩

Spatial pattern of land cover change in china's semiarid environment

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Journal of Arid Land 2009年第1期1卷 16-25页

作者： BaoLin LI1 and QiMing ZHOU2.1 state key {2. of Environment and Resources Information System, {4. of Geographical sciences and Resources Research, Chinese academy of sciences, beijing 100101, china 2.Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong, china Hong Kong Baptist Univ Dept Geog Kowloon Tong Hong Kong Peoples R China Chinese Acad Sci State Key Lab Environm & Resources Informat Syst Inst Geog Sci & Resources Res Beijing 100101 Peoples R China

This study seeks a routine to quantify spatial pattern of land cover changes in semiarid environment of china based on post-classification comparison method. The method consists of three major steps: (1) the image classification and unification of classified results based on two-level land cover classification themes, (2. the establishment of land cover change classes based on an unification land cover classification theme, (3) the reclassification and mapping of land cover change classes with three overall classes including no-change, gain and loss based on the unification land cover class. This method was applied to detect the spatial pattern of land cover changes in Yinchuan Plain, one of famous irrigation agricultural zones of the Yellow River, china. The results showed the land cover had undergone a remarkable change from 1991 to 2.02.in the study area (the changed area was over 30%). Rapid increase of cropland (12.5%), built-up area (131.4.) and rapid decrease of bare ground (51.7%) were alarming. The spatial pattern of land cover changes showed clear regional difference in the study area and was clearly related to human activities or natural factors. Thus, it obtained a better understanding of the human impact on the fragile ecosystem of china’s semiarid environment.

关键词： change detection spatial pattern land cover semiarid zone of china remote sensing human activities

Wetland hydrologic application of satellite altimetry-A case study in the Poyang Lake watershed

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Progress in Natural Science:Materials International 2009年第12期19卷 1781-1787页

作者： Xiaobin Cai~(a,b),Wei Ji~(b,*) a state key {2. of Information Engineering in Surveying,Mapping and remote {4.,Wuhan University,Wuhan 4.0079,china b Department of Geosciences,University of Missouri,Kansas City,Kansas City,MO 64.10,USA [a]state key {2. of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China [b]Department of Geosciences University of Missouri Kansas City Kansas City MO 64110 USA

Hydrologic variation affects many functions of *** and accurately measuring hydrologic dynamics in a wetland watershed has become a fundamental need for estimating functional changes of *** satellite altimeters have become good data sources that can complement the measurements of gauge *** a case project applied in the Poyang Lake watershed,this study has developed a technical approach that integrates the altimeter measurements with the in situ water level *** derived water surface heights with Envisat RA-2.data are compared with the daily observations of in situ water *** average absolute observation difference between the"altimeter station"and its nearest gauge station is 0.307 m,which is comparable to the average differences among the gauge *** results suggest that the derived water surface heights from the altimeter data have a good accuracy,which can be used along with the in situ observations as supplements to fill the ungauged area in Poyang Lake wetlands.

关键词： Satellite altimetry Wetland hydrology Poyang Lake

Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

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Acta Oceanologica Sinica 2010年第1期29卷 79-87页

作者： WANG Zhenyan GAO Shu HUANG Haijun key laboratory of Marine Geology and Environment Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China MOE key laboratory for Coast and Island Development Nanjing University Nanjing 210093China

The exposed area of intertidal zone varies with tidal water level changes, If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the effect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2.January and 7 March 2.02. respectively, were treated by the changing detection analysis using Image Differencing and Post-classification Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly significant in the central Jiangsu coastal waters. The huge differences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the differences in tidal phases for different imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate effectively the effects of water level variations on remote {4. interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote sensing

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., china 2.{2. of Geographic sciences and Resources Research, Chinese academy of sciences, beijing 100101, china 3 School of Geography and Environmental sciences, Jiangxi Normal University, Nanchang 33002., china The key Lab of Poyang Lake Ecological Environment and Resource Development Jiangxi Normal University Nanchang China institute of Geographic sciences and Resources Research Chinese Academy of Sciences Beijing China School of Geography and Environmental sciences Jiangxi Normal University Nanchang China

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 remote 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

Satellite SAR interferometric observations of displacements associated with urban subsidence in Suzhou, Eastern china

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Progress in Natural Science:Materials International 2002年第10期 80-82+84页

作者： WANG Chao, ZHANG Hong, LIU Zhi, CHENG Suozhong and LU Guonian(1. LARSIS, institute of remote sensing applications, Chinese academy of {2., beijing 100101,{4. 2. Department of Geography, Nanjing Normal University, Nanjing 2.0097,{4.) LARSIS Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101China Department of Geography Nanjing Normal University Nanjing 210097 China

SAR interferometry (InSAR) has a high potential for surface displacement mapping in the range from millimeter to meter. In this paper the potential of ERS-1/2.SAR interferometry for mapping subtle land subsidence has been investigated. A time series of ERS-1/2.SAR data from February 1993 to February 2.00 is collected from measurements taken in Suzhou city, Jiangsu Province, china, eight ERS-1/2.SAR images are used to create seven interferograms, and three differential interferograms are produced using the three-pass method, which clearly show the spatial extent of land subsidence. The deformation maps are validated by leveling surveys, the correlation coefficient and standard deviation between them are 0. 94. and 0.1706 respectively. Based on seven benchmarks, the subsidence rates are estimated, the overall trends are in close agreement with InSAR results. The results of study show that for the mapping of land subsidence in urban environments InSAR has a strong potential due to its cost-saving, high res

关键词： SAR interferometry land subsidence Suzhou.

Optimum segmentation of simple objects in high-resolution remote sensing imagery in coastal areas

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Science china Earth sciences 2006年第11期49卷 1195-1203页

作者： CHEN Jianyu1,2. PAN Delu1 & MAO Zhihua1 1. state key {2. of Satellite Ocean Environment Dynamics, Second {4. of Oceanography, state Oceanic Admini- stration, Hangzhou 310012. china 2. Shanghai {4. of Technical Physics, Chinese academy of Science, Shanghai 2.0083, china 1. state key {2. of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China 2. Shanghai institute of Technical Physics Chinese Academy of Science Shanghai 200083 China

The optimum segmentation of ground objects in a landscape is essential for interpretation of high-resolution remotely sensed imagery and detection of objects; and it is also a technical foundation to efficiently use spatial information in remote {2. imagery. Landscapes are complex system composed of a large number of heterogeneous components. There are many explicit homogeneous image objects that have similar spectral character and yet differ from surrounding objects in high-resolution remote {2. imagery. Thereby, a new concept of Distinctive Feature of fractal is put forward and used in deriving Distinctive Feature curve of fractal evolution in multiscale segmentation. Through distinguishing the extremum condition of Distinctive Feature curve and the inclusion relationship of fractals in multiscale representation the Scalar Order is built. This can help to determinate the optimum scale in image segmentation for simple-objects, and the potential meaningful image-object fitting the intrinsic scale of the dominant landscape object can be obtained. Based on the application in high-resolution remote {2. imagery in coastal areas, a satisfactory result was acquired.

关键词： optimum scale, multiscale segmentation, image interpretation, remote sensing, coastal area.