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A novel method of systematic error compensation for a position and orientation system

Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* School of remote {1. and Information Engineering, Wuhan University, Wuhan 43.079, china School of remote {1. and Information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1.2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1.3.,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

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Efficient visualization techniques for high resolution remotely sensed data in a network environment

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Science china(Technological Sciences) 2008年第S1期51卷 124-134页

作者： WENG JingNong1.WU Lun2,HUANG Jian1.XIA YuBin3.& CAI Heng1.1.College of Software,Beihang University,Beijing 1.0083.china 2 Institute of Geographical Information System and remote sensing,Peking University,Beijing 1.0871.china 3.College of Computer,Beihang University,Beijing 1.0083.china 1. College of Software Beihang University Beijing 100083 China2. Institute of Geographical Information System and Remote Sensing Peking University Beijing 100871 China3. College of Computer Beihang University Beijing 100083 China

There are three major research hotspots in efficient visualization techniques of high resolution remotely sensed data in network environment: the data organiza-tion and access in disk storage,the image data stitching and fitting methods,and the network transfers and access. In this paper a new method of "Big File" organi-zation for improving the storage access efficiency of high resolution remote data is presented; a "virtual data source" concept is introduced to solve the stitching problem of remotely sensed data from different sources with different resolutions; a remotely sensed data access engine design based on ATL technique is discussed to process the network transfers and access of remotely sensed data. All these techniques have been adopted in a prototype of digital china named "chinaStar".

关键词： high resolution remotely sensed data spatial index pyramid model LOD Big File

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Geologic body three-dimensional model generation and visualization method

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中国有色金属学会会刊：英文版 2005年第S1期15卷 190-192页

作者： ZHANG Song-mei~(1, 2), LI Jing~1, ZHAO Wen-ji~3. Gong Hui-li~3. Duan Fu-zhou~3. GONG Zhao-ning~3. LI Jia-hong~4 (1. Beijing Normal University, Beijing 100875, china 2. Jilin University, Changchun 13.061, china 3. The Key Lab of Resource Environment and GIS, Beijing 10003., china 4. National {3. sensing center of china, Beijing 100862, china) Beijing Normal Univ Beijing 100875 Peoples R China Jilin Univ Changchun 130061 Peoples R China Key Lab Resource Environm Beijing 100037 Peoples R China GIS Beijing 100037 Peoples R China Natl remote {1. Ctr china Beijing 100862 Peoples R China

The divergence three-dimensional millet-seed body model and the continuous distributing layer-imitating model were introduced, which were used to express geologic body, and the procedure of generating these two models and their merits and demerits were synthesized. Three methods of geologic body’s three-dimensional expression were separately introduced, and the merits of the continuous distributing layer imitating model were proposed as comparing with the divergence three-dimensional millet-seed body model. The three-dimensional cubes were observed from any direction and any tangle with the application of dealing methods such as peeling, hollowing out, transparent or half-transparent.

关键词： geologic body regular grid net irregular triangle net three-dimensional visualization

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Information flow and controlling in regularization inversion of quantitative remote {1.

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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 {1. sensing and GIS, School of Geography, Beijing Normal University, State Key Laboratory of {1. sensing Science, Beijing Key Laboratory for {1. sensing of Environment and Digital Cities, Beijing 1.0875, china Department of Mathematics, Beijing Normal University, Beijing 1.0875, china 1. Research center for {1. 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 {1. data, it is necessary to understand what the information flow in quantitative remote {1. 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 {1., 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.

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Analysis of forest backscattering characteristics based on polarization coherence tomography

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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 {1.,Chengdu 61.054,{1. 2 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 1.01.1.{1. 3.nstitute of Forest Resources Information Technique of Chinese Academy of Forestry,Beijing 1.0091.{1. 4 School of Electronic Engineering,University of Electronic Science and Technology of {1.,Chengdu 61.054,{1. State Key Lab remote {1. 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

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A new trust region algorithm for image restoration

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Science china Mathematics 2005年第2期48卷 169-184页

作者： WEN Zaiwen & WANG Yanfei State Key Laboratory of Scientific Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 1.0080, china National Key Laboratory on {1. sensing Science, Institute of {1. sensing Applications, Chinese Academy of Sciences, Beijing 1.01.1. china 1. State Key Laboratory of Scientific Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. National Key Laboratory on remote {1. Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China

The image restoration problems play an important role in remote {1. and astronomical image analysis. One common method for the recovery of a true image from corrupted or blurred image is the least squares error (LSE) method. But the LSE method is unstable in practical applications. A popular way to overcome instability is the Tikhonov regularization. However, difficulties will encounter when adjusting the so-called regularization parameter a. Moreover, how to truncate the iteration at appropriate steps is also challenging. In this paper we use the trust region method to deal with the image restoration problem, meanwhile, the trust region subproblem is solved by the truncated Lanczos method and the preconditioned truncated Lanczos method. We also develop a fast algorithm for evaluating the Kronecker matrix-vector product when the matrix is banded. The trust region method is very stable and robust, and it has the nice property of updating the trust region automatically. This releases us from tedious finding the regularization parameters and truncation levels. Some numerical tests on remotely sensed images are given to show that the trust region method is promising.

关键词： trust region algorithm, image restoration, Lanczos method, Kronecker matrix-vector product, preconditioning.

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Positioning localities from spatial assertions based on Voronoi neighboring

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Science china(Technological Sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1.2,3.LI GuiCai 1.LIU Yu 2 & YANG Jian 1.1.Shenzhen Key Lab of Recycling Economy,Peking University Shenzhen Graduate School,Shenzhen 51.055,{1. 2Institute of remote sensing and Geographical Information Systems,Peking University,Beijing 1.0871.{1. 3.ollege of Urban and Environmental Science,Peking University,Beijing 1.0871.{1. Peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China Peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

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Lunar surface dielectric constant,regolith thickness, and ~3.e abundance distributions retrieved from the microwave brightness temperatures of CE-1.Lunar Microwave Sounder

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Science china Earth Sciences 2010年第9期53卷 1365-1378页

作者： WANG ZhenZhan1. LI Yun1.2, JIANG JingShan1.& LI DiHui1.1.National Microwave remote {1. Laboratory, center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 1.01.0, {3. 2 Graduate University of Chinese Academy of Sciences, Beijing 1.0049, {3. 1. National Microwave remote {1. Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1.Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3.e content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43. of them are bigger than 5.0 m. The content of 3.e evaluated by retrieved regolith thickness is about 1.03.million tons.

关键词： CE-1 Lunar Microwave Sounder (CELMS) lunar regolith dielectric constant lunar regolith thickness 3.e retrieval

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Detection of the urban heat island in Beijing using HJ-1. satellite imagery

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Science china Earth Sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1.GONG Peng2,ZHOU JinXing3.HUANG HuaBing2 & WANG Lei2 1.Key Laboratory of Silviculture and Conservation,Ministry of Education,Beijing Forestry University,Beijing 1.0083.china 2 State Key Laboratory of remote sensing Science,jointly sponsored by the Institute of remote sensing Applications,Chinese Academy of Sciences and Beijing Normal University,Beijing 1.01.1.china 3.Institute of Desertification Studies,Chinese Academy of Forestry,Beijing 1.0091.china 1. Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China3. Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1. satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1. data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1. data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1. TIR data present a unique opportunity to study thermal environments in cities in china and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm

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Wave Polarization Scattering and Transmission Property in Randomly Distributed Chiral Spheroids

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Journal of Systems Engineering and Electronics 2001年第2期12卷 23-29页

作者： Chang Mei & Jin Yaqiu center for Wave Scattering and {1. sensing, Dept. of Electronic Engineering, Fudan University, Shanghai 20043., P. R. {3. center for Wave Scattering and {1. sensing Dept. of Electronic Engineering Fudan University Shanghai 200433 P. R. China

In this paper, the scattering amplitude functions of a spatially-oriented chiral spheroid are derived. Polarization scattering from a layer of randomly distributed chiral spheroids in the Mueller matrix solution is obtained. Co-polarized and de-polarized backscattering and polarization degree for any polarized incidence are numerically calculated. Transmissions of coherent waves with four Stokes parameters through the layer are also discussed. Comparisons of polarization scattering from the chiral and achiral particulate media demonstrate the chirality effect on wave scattering and transmission.

关键词： Polarization scattering Transmission Scattering amplitude functions Chirality.

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