检索结果-南通市图书馆

A new approach toward object-based change detection

在线全文

学校读者我要写书评

暂无评论

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 43007.,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 university,wuhan 43007.,china 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

A new relative radiometric consistency processing method for change detection based on wavelet transform and a low-pass filter

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第S1期53卷 7-14页

作者： SUN KaiMin1,SUI HaiGang1,2,li DeRen1 & XU Chuan1,2 1 state key laboratory of information engineering in surveying,mapping and remote sensing,wuhan university,wuhan 43007.,china 2 state key laboratory of Subtropical Building Science,South china university of Technology,Guangzhou 510640,china 1. state key laboratory of information engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. state key laboratory of Subtropical Building Science South China University of Technology Guangzhou 510640 China

The research purpose of this paper is to show the limitations of the existing radiometric normalization approaches and their disadvantages in change detection of artificial objects by comparing the existing approaches,on the basis of which a preprocessing approach to radiometric consistency,based on wavelet transform and a spatial low-pass filter,has been *** approach first separates the high frequency information and low frequency information by wavelet ***,the processing of relative radiometric consistency based on a low-pass filter is conducted on the low frequency *** processing,an inverse wavelet transform is conducted to obtain the results *** experimental results show that this approach can substantially reduce the influence on change detection of linear or nonlinear radiometric differences in multi-temporal images.

关键词： wavelet transform radiometric normalization low-pass filter change detection

Image City sharing platform and its typical applications

在线全文

学校读者我要写书评

暂无评论

Science china(information Sciences) 2011年第8期54卷 1738-1746页

作者： SHAO ZhenFeng & li DeRen state key laboratory for information engineering in surveying,mapping and remote sensing,wuhan university,wuhan 43007.,china 1. state key laboratory for information engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

In this paper,the trend of urban spatial information sharing service from the electronic map to image is analyzed and its sharing framework based on service-oriented architecture is ***,the service implementation,feedback data service procedure and its processing service model are explored. Based on the software with independent intellectual property rights,image city of Taizhou is developed as an example to realize various image data and processing servicesLastly,the bright future prospects of image city are described.

关键词： Image City service-oriented architecture image data service function service model service

Post-earthquake assessment of building damage degree using liDAR data and imagery

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2008年第S2期51卷 133-143页

作者： li ManChun1,CHENG liang1,2,GONG JianYa2,liU YongXue1,CHEN ZhenJie1,li FeiXue1,CHEN Gang1,CHEN Dong1 & SONG XiaoGang3 1 Department of Geographic information Science,Nanjing university,Nanjing 210093,china 2 state key laboratory of information engineering in surveying,mapping and remote sensing,wuhan university,wuhan 43007.,china 3 state key laboratory of Earthquake Dynamics,Institute of Geology,china Earthquake Administration,Beijing 100029,china Department of Geographic information Science Nanjing University Nanjing 210093 China state key laboratory of information engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China state key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

Various methods have been developed to detect and assess building's damages due to earthquakes using remotely sensed *** the launch of the high resolution sensors such as IKONOS and QuickBird,it becomes realistic to identify damages on the scale of individual *** the low accuracy of the results has often led to the use of visual interpretation ***,it is very difficult to estimate the degree of building damage(*** damage,moderate damage,or severe damage) in detail using the existing ***,a novel approach integrating liDAR data and high resolution optical imagery is proposed for evaluating building damage degree *** approach consists of two steps:3D building model reconstruction and rooftop patch-oriented 3D change ***,a method is proposed for automatically reconstructing 3D building models with precise geometric position and fine details,using pre-earthquake liDAR data and high resolution ***,focusing on each rooftop patch of the 3D building models,the pre- and post-earthquake liDAR points belonging to the patch are collected and compared to detect whether it was destroyed or not,and then the degree of building damage can be identified based on the ratio of the destroyed rooftop patches to all rooftop *** novelty of the proposed approach is to detect damages on the scale of building's rooftop patch and realize quantitative estimation of building damage degree.

关键词： post-earthquake assessment building damage degree rooftop patch liDAR imagery

A multi-scale and multi-orientation image retrieval method based on rotation-invariant texture features

在线全文

学校读者我要写书评

暂无评论

Science china(information Sciences) 2011年第4期54卷 732-744页

作者： SHAO ZhenFeng,li DeRen & ZHU XianQiang state key laboratory for information engineering in surveying,mapping and remote sensing,wuhan university,129 Luoyu Road,wuhan 43007.,china 1. state key laboratory for information engineering in surveying Mapping and Remote Sensing Wuhan University 129 Luoyu Road Wuhan 430079 China

Texture retrieval is a vital branch of content-based image ***-invariant texture retrieval plays a key role in texture *** paper addresses three major issues in rotation-invariant texture retrieval: how to select the texture measurement methods,how to alleviate the influence of rotation for texture retrieval and how to apply the proper multi-scale analysis theory for texture ***,the spectrum influence between a Radon transform and a Log-polar transform was compared after the rotation effect was *** average retrieval performance of wavelet and NSCT with different retrieval parameters was also *** on such analysis,we developed a multi-scale and multi-orientation texture transform spectrum,as well as a rotation-invariant feature vector and its measurement criteria,which can represent the human visual perception sensitive to texture *** a new rotation-invariant texture retrieval algorithm was *** algorithm was developed based on non-parametric statistical features and it applies low band and high frequency directional bands of NSCT coefficients for coarse filtering and fine retrieval,*** on the Brodatz image database show that the constructed rotation-invariant feature vector is appropriate for capturing major orientations and describing detail ***,the combination of the two-step progressive retrieval strategy and multi-scale analysis method can effectively improve retrieval efficiency while ensuring a high precision compared with traditional algorithms.

关键词： NSCT Log-polar Radon rotation-invariant texture retrieval

GRACE detection of the medium-to far-field coseismic gravity changes caused by the 2004 Mw9.3 Sumatra-Andaman earthquake

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Earthquake Science 2012年第3期25卷 235-240页

作者： Jin li1,2,3 and Wenbin Shen1,3,4, 1 Department of Geophysics, School of Geodesy and Geomatics, wuhan university, wuhan 43007., china 2 key laboratory of Geodynamic Geodesy of Chinese Academy, wuhan 43007., china 3 key laboratory of Geospace Environment and Geodesy (Ministry of Education), wuhan university, wuhan 43007., china 4 state key laboratory of information engineering in surveying, mapping and remote sensing, wuhan 43007., china 1. Department of Geophysics School of Geodesy and Geomatics Wuhan University Wuhan 430079 China 2. key laboratory of Geodynamic Geodesy of Chinese Academy Wuhan 430077 China 3. key laboratory of Geospace Environment and Geodesy (Ministry of Education) Wuhan University Wuhan 430079 China 4. state key laboratory of information engineering in surveying Mapping and Remote Sensing Wuhan 430079 China

Large earthquakes cause observable changes in the Earth’s gravity field, which have been detected by the Gravity Recovery and Climate Experiment (GRACE). Since most previous studies focus on the detection of near-field gravity effects, this study provides the results from the medium- to far-field gravity changes caused by the 2004 Sumatra-Andaman earthquake that are recorded within GRACE monthly solutions. Utilizing a spherical-earth dislocation model we documented that large-scale signals predominate in the global field of the coseismic gravity changes caused by the earthquake. After removing the near-field effects, the coseismic gravity changes show a negative anomaly feature with an average magnitude of -0.18×10-8 m·s-2 in the region ranging ～40° from the epicenter, which is considered as the 'medium ffield' in this study. From the GRACE data released by Center for Space Research from August 2002 to December 2008, we retrieved the large-scale gravity changes smoothed with 3 000 km Gaussian ffilter. The results show that the coseismic gravity changes detected by GRACE in the medium field have an average of (-0.20±0.06)×10-8 m·s-2, which agrees with the model prediction. The detection confirms that GRACE is sensitive to large-scale medium-field coseismic gravitational effects of mega earthquakes, and also validates the spherical-earth dislocation model in the medium field from the perspective of satellite gravimetry.

关键词： GRACE medium-to far-field coseismic gravity change 2004 Sumatra-Andaman earthquake spherical-Earth dislocation model

Processing Approach of Non-linear Adjustment Models in the Space of Non-linear Models

在线全文

学校读者我要写书评

暂无评论

Geo-Spatial information Science 2003年第2期6卷 25-30页

作者： li Chaokui ZHU Qing SONG Chengfangli Chaokui,associate professor,Ph.D,state key laboratory of information engineering in surveying,mapping and remote sensing,wuhan university,129 Luoyu Road,wuhan 43007.,china. state key laboratory of information engineering in surveying Mapping and Remote Sensing Wuhan University

This paper investigates the mathematic features of non-linear models and discusses the processing way of non-linear factors which contributes to the non-linearity of a non-linear model. On the basis of the error definition,this paper puts forward a new adjustment criterion, ***,this paper investigates the solution of a non-linear regression model in the non-linear model space and makes the comparison between the estimated values in non-linear model space and those in linear model space.

关键词： non-linear adjustment model model space multi-robustness

Analysis of forest backscattering characteristics based on polarization coherence tomography

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,li XiaoWen 1,2,CHEN ErXue 3,CHENG Jian 4 & CAO ChunXiang 21 Institute of Geo-Spatial information Science and Technology,university of Electronic Science and Technology of china,Chengdu 610054,china 2 state key laboratory of remote sensing Science,Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of Sciences and Beijing Normal university,Beijing 100101,china 3Institute of Forest Resources information Technique of Chinese Academy of Forestry,Beijing 100091,china 4 School of Electronic engineering,university of Electronic Science and Technology of china,Chengdu 610054,china state key Lab remote sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ Beijing 100101 Peoples R China Univ Elect Sci & Technol china Inst Geospatial Informat Sci & Technol Chengdu 610054 Peoples R China Chinese Acad Forestry Inst Forest Resources Informat Tech Beijing 100091 Peoples R China Univ Elect Sci & Technol china Sch Elect Engn Chengdu 610054 Peoples R China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolinSAR)simulation of forest scene and PolinSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POlinSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POlinSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POlinSAR PCT vertical structure function

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3, li Xiaoying1,2,3, ZHANG Yong1,2,3, ZHAO Feng1,2,3, GU Xingfa1,3,4, ZHU li1,2,3, wang Pengxin5 & MIN Xiangjun6 1. state key laboratory of remote sensing Science Institute of remote sensing Application, CAS, Bei- jing 100101, china 2. Graduate university of Chinese Academy of Sciences, Beijing 100039, china 3. The Center for National Spaceborne Demonstration, Beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of information and Electrical engineering, china Agricultural university, Beijing 100083, china 6. china Center for Resource Satellite Data and Application, Beijing 100830, china 1. state key laboratory of remote sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The Center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate university of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of information and Electrical engineering China Agricultural University 100083 Beijing China 6. china Center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.