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Information flow and controlling in regularization inversion of quantitative remote sensing

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Science china Earth Sciences 2005年第1期48卷 74-83页

作者： YANG Hua, XU Wangli, ZHAO Hongrui, CHEN Xue & WANG Jindi Research Center for remote sensing and GIS, School of Geography, beijing Normal University, State {3. {3. of remote sensing Science, beijing {3. {3. for remote sensing of environment and {13. cities, beijing 100875, china Department of Mathematics, beijing Normal University, beijing 100875, china 1. Research Center for remote sensing and GIS School of Geography Beijing Normal University State Key Laboratory of Remote Sensing Science Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities 100875 Beijing China 2. Department of Mathematics Beijing Normal University 100875 Beijing China

In order to minimize uncertainty of the inversed parameters to the largest extent by making full use of the limited information in remote sensing data, it is necessary to understand what the information flow in quantitative remote sensing model inversion is, thus control the information flow. Aiming at this, the paper takes the linear kernel-driven model inversion as an example. At first, the information flow in different inversion methods is calculated and analyzed, then the effect of information flow controlled by multi-stage inversion strategy is studied, finally, an information matrix based on USM is defined to control information flow in inversion. It shows that using Shannon entropy decrease of the inversed parameters can express information flow more properly. Changing the weight of a priori knowledge in inversion or fixing parameters and partitioning datasets in multi-stage inversion strategy can control information flow. In regularization inversion of remote sensing, information matrix based on USM may be a better tool for quantitatively controlling information flow.

关键词： regularization inversion, information flow, Shannon entropy decrease, information matrix.

Synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data

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Science china(Technological Sciences) 2008年第S2期51卷 176-187页

作者： BAO YunFei1,2,CAO ChunXiang1,ZHANG Hao1,CHEN ErXue3.HE QiSheng1,2,HUANG HuaBing1,LI ZengYuan3.LI XiaoWen1,4 & GONG Peng1 1 State key laboratory of remote {3. Science,jointly sponsored by the Institute for remote {3. Applications of Chinese Academy of Sciences and beijing Normal University,beijing 100101,china 2 Graduate University of the Chinese Academy of Sciences,beijing 100049,china 3.Institute of Forest Resource Information Technique,the Chinese Academy of Forestry,beijing 100091,china 4 Research Center for remote {3. and GIS,Department of Geography and beijing key laboratory for remote {3. of environment and digital Sites,beijing Normal University,beijing 100875,china State key laboratory of remote {3. Science jointly sponsored by the Institute for Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Institute of Forest Resource Information Technique the Chinese Academy of Forestry Beijing 100091 China Research Center for remote sensing and GIS Department of Geography and Beijing Key Laboratory for Remote Sensing of Environment and Digital Sites Beijing Normal University Beijing 100875 China

We proposed a method to separate ground points and vegetation points from discrete return,small footprint airborne laser scanner data,called skewness change *** method,which makes use of intensity of laser scanner data,is especially applicable in steep,and forested *** does not take slope of forested area into account,while other algorithms consider the change of slope in steep forested *** ground points and vegetation points can be used to estimate digital terrain model(DTM) and fractional vegetation cover,respectively.A few vegetation points which were classified into the ground points were removed as noise before the generation of *** method was tested in a test area of 10000 square meters.A LiteMapper -5600 laser system was used and a flight was carried out over a ground of 700―800 *** this tested area,a total number of 1546 field measurement ground points were measured with a total station TOPCON GTS-602 and TOPCON GTS -7002 for validation of DTM and the mean error value is -18.5 cm and the RMSE(root mean square error) is ±20.9 cm.A data trap sizes of 4m in diameter from airborne laser scanner data was selected to compute vegetation fraction *** of fractional vegetation cover was carried out using 15 hemispherical photographs,which are georeferenced to centimeter accuracy by differential *** gap fraction was computed over a range of zenith angles 10° using the gap light analyzer(GLA) from each hemispherical *** R2 for the regression of fractional vegetation cover from these ALS data and the respective field measurements is *** this study presents a method for synchronous estimation of DTM and fractional vegetation cover in forested area from airborne LIDAR height and intensity data.

关键词： LIDAR intensity skewness synchronous DTM fractional vegetation cover

The application of hyperspectral remote sensing to coast environment investigation

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Acta Oceanologica Sinica 2009年第2期28卷 1-13页

作者： ZHANG Liang ZHANG Bin CHEN Zhengchao ZHENG Lanfen TONG Qingxi State key laboratory of remote {3. Science Institute of Remote Sensing Applications Chinese Academy of Science Beijing 100101 China Naval Institute of Hydrographic Surveying and Charting Tianjin 300061 China Center for Earth Observation and digital Earth Chinese Academy of Science Beijing 100190 China

Requirements for monitoring the coastal zone environment are first summarized. Then the appli- cation of hyperspectral remote sensing to coast environment investigation is introduced, such as the classification of coast beaches and bottom matter, target recognition, mine detection, oil spill identification and ocean color remote sensing. Finally, what is needed to follow on in application of hyperspectral remote sensing to coast environment is recommended.

关键词： hyperspectral remote sensing coastal zone ocean color remote sensing

Comments on scaling effect of reciprocity in BRDF study

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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 key 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.

Loose architecture of multi-level massive geospatial data based on virtual quadtree

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Science china(Technological Sciences) 2008年第S1期51卷 114-123页

作者： YANG ChongJun,WU Sheng,REN YingChao,FU Li,ZHANG FuQing,WANG Gang,TAN Jian,LIU DongLin,MA ChaoJi & LIANG Li State key laboratory of remote {3. Science,Jointly Sponsored by the Institute of remote {3. Applications of Chinese Academy of Sciences and beijing Normal University,beijing 100101,china 1. State key laboratory of remote {3. Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

This paper proposed a virtual quadtree (VQT) based loose architecture of multi-level massive geospatial data for integrating massive geospatial data dispersed in the departments of different hierarchies in the same sector into a unified GIS (Geographic Information System) platform. By virtualizing the nodes of the quad-tree,the VQT separates the structure of data organization from data storage,and screens the difference between the data storage in local computer and in the re-mote computers in network environment. And by mounting,VQT easily integrates the data from the remote computers into the local VQT so as to implement seam-less integration of distributed multi-level massive geospatial data. Based on that mode,the paper built an application system with geospatial data over 1200 GB distributed in 12 servers deployed in 12 cities. The experiment showed that all data can be seamlessly rapidly traveled and performed zooming in and zooming out smoothly.

关键词： massive geospatial data virtual quadtree loose architecture

Development of distributed time-variant gain model for nonlinear hydrological systems

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Science china Earth Sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2, WANG Gangsheng1, TAN Ge1, YE Aizhong2 & G. H. Huang3.1. key laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101,{3. 2. State key laboratory of Water Resources & Hydropower Engineering Sciences, Wuhan University, Wuhan 43.072,{3. 3. Faculty of Engineering, University of Regina, 3.3. Wascana Parkway, Regina, Sask., S4S 0A2, Canada Correspondence should be addressed to Xia Jun 1. key laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. State key laboratory of Water Resources & Hydropower Engineering Sciences Wuhan University 430072 Wuhan China 3. Faculty of Engineering University of Regina 3737 Wascana Parkway S4S 0A2 Sask Regina Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of digital Elevation Model (DEM), remote sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern{3. and the Chaobai River basin located in the semihumid region of northern{3.. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

Ecological Instream Flow Requirements Calculation of Pihe River by Montana Methodology in Sichuan Basin,china

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Ecological Instream Flow Requirements Calculation of Pihe Ri...

基于Multigen/Vega的校园VR仿真系统的实现——以中国矿业大学为例

2007中国科协年会

作者： W.Ouyang~(1,2) F.H.Hao~1 H.Chen~1 X.Wang~1 S.T.Yang~3.1.School of environment,State key laboratory of Water environment Simulation,2.{3. Normal University 2.International Institute for Geo-Information Science and Earth Observation(ITC),Netherlands 3.State key laboratory of remote sensing Science,{3. key laboratory for remote sensing of environment and digital cities,School of Geography,{3. Normal University

With the rapid economic developments in china,the future water resource developments should be sustainable and that a component of the natural flow of rivers should be reserved to ensure diverse ecological *** last 15 years,ecological instream flow requirements(EIFR)research of river was one of the main and hot fields for eco-hydrology *** this paper,we summarized the research advance of eco-hydrology and also,the conception of the EIFR was also followed and *** ecological instream flow has three main functions:maintain the water ecological environments,dilute pollutants and *** coordinate with the water resource allocation,we evaluated EIFR of Pihe River section in every 12 month of three typical years (1968,1986 and 1987).Pihe River is one of the main waterr sources for the cities in Sichuan Basin and locates in the lower beach of famous Doujiang *** Montana methodology was widely applied in water requirements estimate and proved *** on natural characters of Pihe River,minimum and optimum water requirement of aquatic habitat for the river maintenance were *** water requirement of Pihe River was computed too,which is related with the width of water surface,the river length and evaporation depth. Considering the water quality goal,diluting pollutant water requirement was taken into *** the EIFR of the river of 12 month were ultimateS,*** them,that was 20.64m/s and the minimum eco-environmental water requirement of the river was 25.84m/s.

关键词： Eco-environmental water requirements Water resource allocation Water quality goal Pollutant dilute water requirement

来源： cnki会议评论

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cnki会议

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系统仿真学报 2004年第9期16卷 1995-1998页

作者：宋金玲肖寒盛业华王锦地北京师范大学地理学与遥感科学学院遥感与地理信息系统研究中心遥感科学国家重点实验室环境遥感与数字城市北京市重点实验室北京100875 中国矿业大学环测学院徐州221008 南京师范大学地理科学学院南京210097

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用... 详细信息

虚拟现实技术对于城市规划和城市的可持续发展有着非常重要的意义,它的长足进步,为真实景观的再现提供了有效手段。本论文在已有的二维地理信息系统数据的基础上进行校园数据的获取与组织,利用虚拟现实技术实现校园全景的三维重建,采用层次型与面向对象相结合的三维数据结构,构造了校园全景的仿真模型,并实现了校园全景的驱动显示,为校园规划和可持续发展更可靠的保证。

关键词：虚拟现实 Multigen Vega 仿真

A distributed spatial computing prototype system in grid environment

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Science china(Technological Sciences) 2010年第S1期53卷 25-32页

作者： WU Lun,YAN MengLong,GAO Yong,YANG ZhenZhen,ZHAO Yong & CHEN Bin Institute of remote sensing and Geographic Information System,Peking University,beijing 100871,{3. 1. Institute of remote sensing and Geographic Information System Peking University Beijing 100871 China

digital Earth has been a hot topic and research trend since it was proposed,and digital china has drawn much attention in *** a {3. technique to implement digital china,grid is an excellent and promising concept to construct a dynamic,inter-domain and distributed computing *** is appropriate to process geographic information across dispersed computing resources in networks effectively and cooperatively.A distributed spatial computing prototype system is designed and implemented with the Globus *** important aspects are discussed in *** architecture is proposed according to the characteristics of grid firstly,and then the spatial resource query and access interfaces are designed for heterogeneous data *** open-up hierarchical architecture for resource discovery and management is represented to detect spatial and computing resources in grid.A standard spatial job management mechanism is implemented by grid service for convenient *** addition,the control mechanism of spatial datasets access is developed based on *** prototype system utilizes the Globus Toolkit to implement a common distributed spatial computing framework,and it reveals the spatial computing ability of grid to support digital china.

关键词： distributed geographic information processing grid computing digital china GIS