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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 43.079,china 2 State Key Laboratory of Subtropical Building Science,South{3. University of Technology,Guangzhou 510640,china State Key Laboratory of Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China State Key Laboratory of Subtropical Building Science South China University of Technology Guangzhou 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

Study on the detection of abnormal sounding data based on LS-SVM

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Acta Oceanologica Sinica 2010年第6期29卷 115-120页

作者： HUANG Xianyuan ZHAI Guojun SUI Lifen CHAI Hongzhou Institute of surveying and mapping Information Engineering University Zhengzhou 450052 China Naval Institute of Hydrographic surveying and Charting Tianjin 300061 China

A new method of detecting abnormal sounding data based on LS-SVM is *** theorem proves that the trend surface filter is the especial result of *** order to depict the relationship of trend surface filter and LS-SVM,a contrast is *** example shows that abnormal sounding data could be detected effectively by LS-SVM when the training samples and kernel function are reasonable.

关键词： LS-SVM trend surface filter kernel function abnormal sounding data

An Evaluation of BeiDou Navigation Satellite System

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An Evaluation of BeiDou Navigation Satellite System

The retrieval of two-dimensional distribution of the earth's surface aerodynamic roughness using SAR image and TM thermal infrared image

第三届中国卫星导航学术年会

作者： Gao Weiguang1,2, Su Mudan1, Li Chang1, Li Junzheng3. Hu Zhigang4, Feng Laiping5 (1. beijing Institute of Tracking and Telecommunication Technology, beijing 100094, china 2. School of Electronic and Information Engineering, beijing University of Aeronautics and Astronautics, beijing, 100191,china 3. Institute of surveying and mapping, University of Information Engineering, Zhengzhou 450052, china 4. GNSS research center of Wuhan University, Wuhan, 43.079, china 5. Xian Research Institute of surveying and mapping, Xian 710054, china 5. Xian Research Institute of surveying and mapping, Xian 710054, china)

＜正＞The performance evaluation of Beidou satellite navigation system is the preconditions and basic elements of Beidou service. According to the integrated test task of Beidou system, the evaluation methods and algo... 详细信息

关键词： 1. Beidou satellite navigation system. 2. accuracy. 3. continuity. 4. availability. 5. evaluation

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Science china Earth Sciences 2004年第12期47卷 1134-1146页

作者： ZHANG Renhua 1 ,WANG Jinfeng 1 ,ZHU Caiying 1,2 ,SUN Xiaomin 1 & ZHU Zhilin 1 1.Institute of Geographical Sciences and Natural Resources,Chinese Academy of Sciences,beijing 100101,china 2.Institute of surveying and {3.,Information Engineering University of the Chinese People’s Liberation Army,Zhengzhou 450052,china Chinese Academy of Sciences Institute of Geographical Sciences and Natural Resources Beijing China Information Engineering University of the Chinese People’s Liberation Army Institute of Surveying and Mapping Zhengzhou China

After having analyzed the requirement on the aerodynamic earth’s surface rough- ness in two-dimensional distribution in the research field of interaction between land surface and atmosphere, this paper presents a new way to calculate the aerodynamic roughness using the earth’s surface geometric roughness retrieved from SAR (Synthetic Aperture Radar) and TM thermal infrared image data. On the one hand, the SPM (Small Perturbation Model) was used as a theoretical SAR backscattering model to describe the relationship between the SAR back- scattering coefficient and the earth’s surface geometric roughness and its dielectric constant re- trieved from the physical model between the soil thermal inertia and the soil surface moisture with the simultaneous TM thermal infrared image data and the ground microclimate data. On the basis of the SAR image matching with the TM image, the non-volume scattering surface geo- metric information was obtained from the SPM model at the TM image pixel scale, and the ground pixel surface’s equivalent geometric roughness—height standard RMS (Root Mean Square) was achieved from the geometric information by the transformation of the typical to- pographic factors. The vegetation (wheat, tree) height retrieved from spectrum model was also transferred into its equivalent geometric roughness. A completely two-dimensional distribution map of the equivalent geometric roughness over the experimental area was produced by the data mosaic technique. On the other hand, according to the atmospheric eddy currents theory, the aerodynamic surface roughness was iterated out with the atmosphere stability correction method using the wind and the temperature profiles data measured at several typical fields such as bare soil field and vegetation field. After having analyzed the effect of surface equivalent geo- metric roughness together with dynamic and thermodynamic factors on the aerodynamic surface roughness within the working area, this paper first establishe

关键词： surface geometric roughness, aerodynamic surface roughness, SAR backscattering model, moisture retrieval model, roughness transformation model.

A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin

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Science china Earth Sciences 2006年第12期49卷 1299-1310页

作者： SONG Xianfang1, LIU Xiangchao1, 2, XIA Jun1, YU Jingjie1 & TANG Changyuan1, 3.1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Re- sources Research, Chinese Academy of Sciences, beijing 100101, china 2. College of River and Ocean, Chongqing Jiaotong University, Chongqing 400074, china 3. Chiba University, Chiba 263.8522, Japan Key Laboratory of Water Cycle and Related Land Surface Processes Institut of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China College of River and Ocean Chongqing Jiaotong University Chongqing China Chiba University Chiba Japan

The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, environmental isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, beijing. The field surveying and sampling for spring, river and well water were finished in 2002 and 2003. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly.

关键词： environmental isotope,hydrochemistry,surface water,groundwater,interaction.

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 2052 and 2203.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 = 1.921 and R2 = 0.627. 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

Methods of 3. map storage based on geo-referenced image database

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中国有色金属学会会刊：英文版 2011年第S3期21卷 654-658页

作者： YUAN Zhan-liang1, 2, LI Xun1, WANG Jin-ling1, YUAN Qi-qi1, XU Dan2, DIAO Jing-jing2 1. School of surveying and Spatial Information Systems, University of New South Wales, NSW 203., Australia 2. School of surveying and mapping, Henan Polytechnic University, Jiaozuo 454000,{3. School of surveying and Spatial Information Systems University of New South Wales NSW 2032 Australia School of surveying and mapping Henan Polytechnic University Jiaozuo 454000 China

In order to store and manage a large amount of ground and indoor image data with high resolution, an integrated data management system needs to be developed. Possible strategies for this purpose were discussed together with initial test on the newly defined 3. maps. The features of such 3. maps, data organization, key techniques used for the map storage, such as image compression based on wavelet transformation, quadtree index, update and retrieval, were analyzed, with the goals of bringing some profits to the storage and management of the digital data in the visual construction of digital mine, digital city and digital community.

关键词： 3. map geo-referenced image image database storage technology

Ionosphere-free Combinations for Triple-frequency GNSS with Application in Rapid Ambiguity Resolution over Medium-Long Baselines

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Ionosphere-free Combinations for Triple-frequency GNSS with ...

A new method for mining deformation monitoring with GPS-RTK

第三届中国卫星导航学术年会

作者： Li Jinlong1, Yang Yuanxi2, Xu Junyi1, He Haibo3. Guo Hairong3. Institute of surveying and mapping, Information Engineering University, Zhengzhou 450052, china 2 Xi’an Research Institute of surveying and mapping, Xi’an 7100545, china 3.beijing Global Information Center of Application and Exploitation, beijing 100094, china

Aiming at rapid precise positioning by triple-frequency Global Navigation Satellite System （GNSS） over medium-long baselines, the application of triple-frequency ionosphere-free combinations in ambiguity resolution and precise positioning is analyzed. The analytical expression of linear coefficients of them is deduced, and the influences of various errors on ambiguity resolution and precise positioning are evaluated. Considering that the wavelength of optimal ionosphere-free combinations is too small, a method for decomposing the ambiguity of triple-frequency ionosphere-free combinations is presented, and the formula to calculate the virtual wavelength of them is given. In addition, an algorithm for narrow-lane ambiguity resolution is proposed, which is immune to systematic errors. It is proved that the resolutions of narrow-lane ambiguity by this proposed method are equal, with any wide-lane combinations that the sum of linear coefficients of them is equal to zero.

关键词： triple-frequency ionosphere-free combination geometry-free and ionosphere-free combination medium-long baseline ambiguity resolution

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中国有色金属学会会刊：英文版 2011年第S3期21卷 659-664页

作者： GAO Jing-xiang1, 2, LIU Chao2, WANG Jian1, 2, LI Zeng-ke2, MENG Xiang-chao2 1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of surveying and mapping, china University of Mining and Technology, Xuzhou 221116, china 2. School of Environment and Spatial Informatics, china University of Mining and Technology, Xuzhou 221116, china Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of surveying and mapping China University of Mining and Technology Xuzhou 221116 China School of Environment and Spatial Informatics China University of Mining and Technology Xuzhou 221116 China

Based on ranging intersection theory, a new method which is simple and easy to operate was proposed for data collection in the mine surface deformation monitoring with GPS-RTK centering rod measurements. It can fully eliminate the inevitable shaking error and the vertical deflection, and to some extent weaken the multipath effect on the estimates of coordinates in a relatively short period of time, using high-frequency observations. The results show that three-dimensional coordinates with a height accuracy better than 1 cm, horizontal accuracy better than 2-4 cm can be achieved through only 15-3. s continuous observation by 20 Hz high-frequency and effectively improve the measurement accuracy and efficiency of RTK, fully satisfying the high-speed and high-precision data acquisition in mine surface subsidence deformation monitoring.

关键词： GPS rover pole multipath delay deformation monitoring

Variational solution about over-determined geodetic boundary value problem and its related theories

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Science china Earth Sciences 2007年第4期50卷 555-562页

作者： YU JinHai1,2 & PENG FuQing3.1 Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 43.077, china 2 College of Earth Scienc, Graduate University of Chinese Academy of Sciences, beijing 100049, china 3.Zhenghou Institute of {3. and mapping, Zhengzhou 450052, china Institute of Geodesy and Geophysics Chinese Academy of SciencesWuhan 430077China College of Earth Scienc Graduate University of Chinese Academy of SciencesBeijing 100049China Zhenghou Institute of surveying and mapping Zhengzhou 450052China

A new solving method for Laplace equation with over-determined geodetic boundary conditions is pro- posed in the paper, with the help of minimizing some kinds of quadratic functional in calculus of variation. At first, the so-called variational solution for over-determined geodetic boundary value problem is defined in terms of principles in calculus of variation. Then theoretical properties related with the solution are derived, especially for its existence, uniqueness and optimal approximation. And then the computational method of the solution is discussed, and its expression is exhibited under the case that all boundaries are spheres. Finally an arithmetic example about EGM96 gravity field model is given, and the computational results show that the proposed method can efficiently raise accuracy to deal with gravity data. In all, the variational solution of over-determined geodetic boundary value problem can not only fit to deal with many kinds of gravity data in a united form, but also has strict mathematical basements.

关键词： earth’s gravity field over-determined boundary value problem quadratic functional. variational solution optimal approximation