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Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1, NIU Hai-peng1, LIU Jin-ping2.1. College of surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, china 2. College of Geographic Sciences, Chongqing Normal University, Chongqing 400047, china [a] College of surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] College of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, china, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 11.7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62.; and that higher than 60% accounts for 2.%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

A single observer location method under the scatter signals position disturbance situation:the constraint total least square method

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Science china(Information Sciences) 2011年第1期54卷 146-152页

作者： YANG TianChi1,YU ChaoQun2.WANG TianPeng1 & JIN Liang1 1National Digital Switching System Engineering and Technological Research Center, Zhengzhou 450002.china 2.1} and {2. College of Information Engineering University, Zhengzhou 450002.china 1. National Digital Switching System Engineering and Technological Research Center Zhengzhou 450002 China2. Surveying and Mapping College of Information Engineering University Zhengzhou 450002 China

A target position can be estimated using position information from scattered signals in the nonline-of-sight propagation environment in a single observer location *** is always an error in the final estimated result of the position obtained using scatter signals because measurement noise is *** reduce the total error of the system,we propose a method of converting the problem of optimizing location into a one of solving the extremes of the *** the problem of how to solve the extremes of the constraints is converted into an unconstrained problem by using the constrained total least squares(CTLS) ***,the Newton iteration method is used to obtain the optimized *** results also verify the capability of this method.

关键词： scatter position disturbing VOCTLS single observer location Newton iteration

A fusion algorithm for remote sensing images based on nonsubsampled pyramids and bidimensional empirical decomposition

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Science china(Technological Sciences) 2010年第S1期53卷 196-204页

作者： ZHANG XiaoDong 1,WANG WenBo 2.WANG DiFeng 3 & ZHANG Yu 4 1 State Key Laboratory of Information Engineering in surveying,mapping and Remote Sensing,Wuhan University,Wuhan 430079,{2. 2.College of Sciences,Wuhan University of Science and Technology,Wuhan 430065,{2. 3State Key Laboratory of Satellite Ocean Environment Dynamics,Second Institute of Oceanography,State Oceanic Administration,Hangzhou 310012.{2. 4 Spatial Information Technology Application Research Institute,Changjiang River Scientific Research Institute,Wuhan 430010,{2. Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430079 Peoples R China Wuhan Univ Sci & Technol Coll Sci Wuhan 430065 Peoples R China State Ocean Adm Inst Oceanog 2 State Key Lab Satellite Ocean Environm Dynam Hangzhou 310012 Zhejiang Peoples R China Changjiang River Sci Res Inst Spatial Informat Technol Applicat Res Inst Wuhan 430010 Peoples R China

In order to improve the quality of remote sensing image fusion,a new method combining nonsubsampled Laplacian pyramid (NLP)and bidimensional empirical mode decomposition(BEMD)is ***,the high resolution panchromatic image (PAN)is decomposed using NLP until the approximate component and the low resolution multispectral image(MS)contain features with a similar ***,the approximation component and the MS are decomposed by BEMD,resulting in a number of bidimensional intrinsic mode functions(BIMF)and a residue *** instantaneous frequency is computed in 4 directions of the *** the positive or negative coefficients in the corresponding position,a weighted algorithm is designed for fusing the high frequency details using the instantaneous frequency and the coefficient absolute value of the BIMFs as fusion *** fused image is then obtained through inverse BEMD and *** results have illustrated the advantage of this method over the IHS,DWT andà-Trous wavelet in both spectral and spatial detail qualities.

关键词： bidimensional empirical mode decomposition nonsubsampled pyramid instantaneous frequency remote sensing image fusion

Automatic generalization of metro maps based on dynamic segmentation

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Science china(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2.& ZHANG Yi 2.1 Institute of Geography and Remote Sensing,beijing Normal University,beijing 100875,{2. 2.Institute of Remote Sensing and Geographic Information System,Peking University,beijing 100871,{2. 1. Institute of Geography and Remote Sensing Beijing Normal University Beijing 100875 China 2. Institute of Remote Sensing and Geographic Information System Peking University Beijing 100871 China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

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

Precise point positioning and its application in mining deformation monitoring

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中国有色金属学会会刊：英文版 2011年第S3期21卷 499-505页

作者： XU Chang-hui1, 2. WANG Jin-ling2. GAO Jing-xiang1, WANG Jian1, HU Hong1 1. School of Environment and Spatial Information, china University of Mining and Technology, Xuzhou 2.116, china 2. School of {2. and Spatial Information Systems, University of New South Wales, Sydney 2.52. Australia [a] School of Environment and Spatial Information China University of Mining and Technology Xuzhou 22116 China [b] School of surveying and Spatial Information Systems University of New South Wales Sydney 2052 Australia

Precise point positioning (PPP)-based deformation monitoring scheme is presented for the use in mining deformation monitoring. Within the solutions of daily observation, outliers are detected and removed to avoid any potential misinterpretation of the results and then the deformation can be extracted by the coordinate differences between the two consecutive solutions. Meanwhile, because of the special location of a rover station in mining areas, the satellite geometry may be insufficient for a reasonable PPP solution, and the multipath impact an also be significant. Therefore, it is necessary to predict the satellite geometry before any daily observation. To evaluate the ability of extracting the deformation using the PPP-based method, various quality measures were introduced. The results of three datasets of the same station show that the precision of deformation monitored by PPP can reach up to cm level and even mm level.

关键词： precise point positioning deformation monitoring outlier identification geometry multipath

Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN Li-yan, WANG Meng, XUE Hai-bing College of Geosicence and surveying Engineering, china University of Mining & Technology, {2. 100083, china College of Geosicence and surveying Engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion

Velocity and pressure distributions in discharge tunnel of rotary-obstruction composite inner energy dissipation

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Science china(Technological Sciences) 2011年第S1期54卷 111-117页

作者： CAO ShuangLi 1,NIU ZhengMing 1,YANG Jian 2.& LU HongBo 1 1 Xi’an University of Technology,Xi’an 710048,china 2.china Water Resources Pearl River Planning,{2. & Designing Co.Ltd,Guangzhou 510610,china Xian Univ Technol Xian 710048 Peoples R China china Water Resources Pearl River Planning Survey Guangzhou 510610 Guangdong Peoples R China

On the basis of model test and theoretical analysis of velocity and pressure distributions,an hypothesis is presented that the distribution of tangential velocity in radial direction seems to be a combinational distribution of a quasi-free vortex and a quasi-forced vortex for the discharge tunnel of rotary-obstruction composite inner energy *** variations of corresponding parameters about the hypothesis are obtained under test conditions in this *** formula of pressure distribution in radial direction is deduced theoretically,and the theoretical values of pressure distribution computed by the formula are well consistent with the measured ones,showing that the formula is correct and can be applied to the computation and analysis of pressure distribution of this discharge tunnel.

关键词： discharge tunnel rotary-obstruction composite inner energy dissipater model test assumption of velocity distribution the formula of pressure distribution

Multi-source geospatial information integration and sharing in Virtual Globes

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Science china(Technological Sciences) 2010年第S1期53卷 1-6页

作者： GONG JianYa,XIANG LongGang,CHEN Jing & YUE Peng State Key Laboratory of Information Engineering in surveying,mapping and Remote Sensing,Wuhan University,Wuhan 430072.{2. Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R Wuhan 430072 Peoples R China

Massive volumes of global geospatial information are being collected by newly designed acquisition devices and generated by various geospatial *** poses a critical challenge to efficiently organize and effectively integrate global multi-source geospatial *** paper introduces a global seamless data model for the organization of huge multi-source,multi-resolution and multi-temporal geospatial *** on this data model,the management of the global multi-resolution pyramid is discussed in *** integrate geospatial data and processing functions from various GIS systems,a service-oriented framework is presented through the technology of Virtual ***,a Virtual Globe system,GeoGlobe,is developed and illustrated.

关键词： Virtual Globe geospatial information multi-resolution pyramid Web service GeoGlobe