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Multiresolution Terrian Model in GIS

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测绘学报 2002年第Z1期31卷 92-98页

作者： ZHANG Jin 1,TONG Xiao hua 2 (1. department of surveying and mapping, taiyuan {4. of Technology, taiyuan 03.02.,china 2. department of surveying and Geo informatics, Tongji {4., Shanghai 200092,china) department of surveying and mapping Taiyuan University of Technology Taiyuan 030024 department of surveying and Geo-informatics Tongji University 上海 200092

DEM, which becomes a major component of geographic information processing in earth and engineering sciences, has been studied in the GIS literature for a long time. We use DEM to represent the terrain in GIS. The more data are available, the better representations of a terrain can be built. But not all tasks in the framework of a given application necessarily require the same accuracy, and even a single task may need different levels of accuracy in different areas of the domain. Multiresolution models, such as LOD, offer the possibility of representing and analyzing a terrain at a range of different levels of detail. In this paper, some key issues in multiresolution DEM model are studied. Three main models are focused on Hierarchical TIN(HTIN), multiresolution terrain model based Delaunay and Hierarchical Dynamic Simplification. The advantages and disadvantages of these methods are analyzed. The technology of tile to tile edge match is studied to maintain the consistency between adjacent edges and tile edges in HTIN model. And the Hypergraph based Objected oriented Model(HOOM) is presented to divide and code spatial area and describe the terrain feature in adding and deleting points based on Delaunay rule retriangulating. The conclusions have been drawn in the end.

关键词： DEM multiresolution LOD GIS

High-accuracy topographical information extraction based on fusion of ASTER stereo-data and ICESat/GLAS data in Antarctica

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Science china Earth Sciences 2009年第5期52卷 714-722页

作者： E DongChen1,3,SHEN Qiang2,XU Ying1,3 & CHEN Gang4.1 Chinese Antarctic Center of surveying and mapping,Wuhan university,Wuhan 4.0079,china 2 Institute of Seismology{4. Earthquake Administration,Wuhan 4.0071,china 3 Key Laboratory of Polar surveying and mapping,State Bureau of surveying and mapping,Wuhan university,Wuhan 4.0079,china 4.department of Geography,university of Calgary,Calgary,Alberta T2N 1N4.Canada Chinese Antarctic Center of surveying and mapping Wuhan University Wuhan 430079 China Institute of Seismology china Earthquake Administration Wuhan 430071 China Key Laboratory of Polar surveying and mapping State Bureau of Surveying an

In order to better support Antarctic inland ice sheet expedition from Zhongshan Station to Dome A,the topographic data are *** present,although the entire Antarctic DEM provided by RAMP(Ra-darsat Antarctic mapping Project) was estimated at the highest horizontal(spatial) resolution of about 200 m,the real horizontal resolution of the DEM varies from place to place depending on the density and scale of the original source *** ice shelves and the inland ice sheet,the horizontal resolution is about 5 km;the vertical accuracy is estimated to be ±50 m in interior East Antarctic ice sheet and away from the mountain ***,more accurate topographic data are unavailable in *** order to meet the requirements of high-accuracy topographic information for further researches,this paper mainly addresses a fusion study of ASTER stereo pairs and ICESat/GLAS altimetry data for extraction of high-accuracy DEM in East Antarctica,based on the high horizontal resolution(15 m) of ASTER and vertical accuracy(13.8 cm) of ICESat/***,some altimetry data were selected as vertical control points to reduce errors of image correlation matching during the extraction of ASTER-based ***,ice sheet altimetry data derived from ICESat were used to generate DEM ranging from 75° to 81°S because existing ASTER data do not cover this area and high density of the coverage of ICESat altimetry ***,the DEM in coverage of the expedition route was *** analysis of result reveals that the DEM accuracy is improved *** absolute vertical accuracy of DEM is higher than 15 m in some cases and higher than 30 m for all the areas along the expedition route except from the 009-001 scene;the interior accuracy is higher than 15 m and higher than 7 m in some *** can meet the requirements of topographic map at 1:50000 scale,which is an economic and advantageous method to produce the topographic products.

关键词： DEM Antarctica Zhongshan Station Dome A ASTER ICESat GLAS

VERTEX-PRIMITIVE 1/2-TRANSITIVE GRAPHS

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Systems Science and Mathematical Sciences 1996年第1期9卷 76-82页

作者： DU Shaofei(department of Mathematics, Shanxi university, taiyuan 030006, china) 山西大学数学系山西太原 030006

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ＶＥＲＴＥＸ－ＰＲＩＭＩＴＩＶＥ１／２－ＴＲＡＮＳＩＴＩＶＥＧＲＡＰＨＳ￥ＤＵＳｈａｏｆｅｉ（ＤｅｐｏｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｈａｎｘｉＵｎｉｖｅｒｓｉｔｙ，Ｔａｉｙｕａｎ０３０００６，Ｃｈｉｎａ）Ａｂｓｔｒａｃｔ：Ｉｎｔｈｉｓｐａ...

关键词： transitive graph orbital graph primitive group.

Error matching detection and robust estimation adjustment approach for map conflation

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Science china(Technological Sciences) 2008年第S1期51卷 48-61页

作者： TONG XiaoHua & DENG SuSu department of surveying and Geo-informatics,Tongji university,Shanghai 200092,china Tongji Univ Dept Surveying & Geoinfromat Shanghai 200092 Peoples R China

The conflation of geographic datasets is one of the key technologies in the realm of spatial data capture and integration in geographic information system (GIS). Map conflation is a complex process of matching and merging spatial data. Due to various reasons such as errors in original data related to map data discrepancies,a great amount of uncertainties exists during the process and this will result in errors in featuring matching,especially point feature. Thus,it is vital to develop the method to detect the errors in feature matching and further the conflation results will not be affected. In this paper,error matching detection and robust estimation adjustment methods are proposed for map conflation. The characteristics of errors in feature matching are first analyzed,then a new approach for map conflation based on the least-squares adjustment is presented,and a robust estimation adjustment method is further proposed to detect and process matching errors. The results of the map conflation test show that the proposed method not only determines the errors in feature matching,but also obtains the optimal merging results in map conflation.

关键词： map conflation robust estimation error feature matching uncertainty

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4. LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3, ZHANG Qin4.1. School of Survey and Land Information Engineering, Henan Polytechnic university, Jiaozuo 4.4.03, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of surveying and mapping, Henan Polytechnic university, Jiaozuo 4.4.03, china 3. College of Resources and Civil Engineering, Northeastern university, Shenyang 110819, china 4. College of Geology Engineering and Geomatics, Chang’an university, Xi’an 710054. china [a] School of Survey and Land Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of surveying and mapping Henan Polytechnic University Jiaozuo 454003 China [c] College of Resources and Civil Engineering Northeastern University Shenyang 110819 China [d] College of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3 & WANG YingYing4.1 Institute of Geophysics and Geomatics,china university of Geosciences,Wuhan 4.0074.china 2 department of Geography,Hong Kong Baptist university,Hong Kong 3 State Key Laboratory of Information Engineering in surveying,mapping and Remote Sensing,Wuhan university,Wuhan 4.0074.china 4.Hubei Provincial Bureau of Meteorology,Wuhan 4.0074.china 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

Changes in Autoantibodies against β1-Adrenoceptor and M2-Muscarinic Receptor during Development of Renovascular Hypertension in Rats

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 793-797页

作者： Jian-Ming ZHI*, Rong-Fang CHEN1, Heng WU2, Hui-Rong LIU2, and Rong-Rui ZHAO2 department of Physiology, Shanghai Second Medical university, Shanghai 200025, china 1department of Toxicology, Second Military Medical university, Shanghai 2004.3, china 2 department of Physiology, Shanxi Medical university, taiyuan 030001, china department of Physiology Shanghai Second Medical UniversityShanghai 200025 China department of Toxicology Second Military Medical UniversityShanghai 200433 China department of Physiology Shanxi Medical UniversityTaiyuan 030001 China

In an experimental rat’s renovascular hypertension model, we studied the genesis of anti- cardiac β1-adrenoceptor and M2-muscarinic receptor autoantibodies in relation to the changes in immunological function during the development of renal hypertension. The biological activities of these autoantibodies were also examined. It was shown that after two weeks of operation both the frequency of occurrence and the titre of autoantibodies to cardiac β1-adrenoceptor and M2-muscarinic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 10 weeks. Meanwhile the ratio of CD4./CD8 + + was also undergone an initial increase followed by gradual recovery and correlated well with the changes in antibody titre. The biological effects of these autoantibodies displayed an “agonistic-like” activities on the beating frequency of cultured neonatal cardiomyocyte. It is suggested that autoimmune mechanisms are involved in the pathogenesis of renal hypertension and the cardiac receptor autoantibodies might be one of the mechanisms leading to cardiac dysfunction.

关键词： autoantibody renal hypertension cardiac receptor immunology

Improved threshold retracker for satellite altimeter waveform retracking over coastal sea

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Progress in Natural Science:Materials International 2006年第7期16卷 732-738页

作者： GUO Jinyun, HWANG Cheiway, CHANG Xiaotao and LIU Yuting ( department of Land Information and surveying Engineering, Xuzhou Normal university, Xuzhou 221116, china Departmenl of Civil Engineering, National Chiao Tung university, Hsinchu 30050, Taiwan, china Institute of Geodesy, china Academy of surveying and mapping, Beijing 100039, china) [a]department of Land information and surveying Engineering Xuzhou Normal University Xuzhou China [b]department of Civil Engineering National Chiao Tung University Taiwan China [c]Institute of Geodesy China Academy of Surveying and Mapping Beijing China

Data quality is a key factor for the application of satellite altimetry to geodesy and oceanography. Accuracy of altimetry is limited in the coastal area because the altimeter waveforms are seriously contaminated by topography and environmental pollution. So waveform retracking is needed to compute the range correction of geophysical data records (GDRs) for better accuracy. In this paper, a new waveform retracker named the improved threshold retracker (ITR) is put forward. The retracker first builds sub-waveforms based on leading edges detected in a waveform, then determines the middle point of each leading edge to compute the retracking range correction, finally calculates the referenced sea surface heights according to the geoid undulation from a local geopotential model and tide heights from an ocean tide model, and compares it with all retracking ranges to determine the best one. As a test, altimeter waveforms of Geosat/GM are retracked around the Taiwan coastal area. The result shows that accuracy of ITR method is two times better than that of theβ-5-pa-rameter function-fitting method and threshold method, and three times better than that of GDRs. ITR can efficiently improve the altimetry accuracy of the coastal sea area.

关键词： satellite altimetry waveform retracking improved threshold retracker sub-waveform.

“有效降低全社会物流成本”研讨会专家观点综述

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中国流通经济 2024年第5期38卷 3-17页

作者：本刊编辑部《中国流通经济》编辑部

2024.2月24.,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024.4.24.,北京物资学院党委宣传部、杂志社、科研处... 详细信息

2024.2月24.,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024.4.24.,北京物资学院党委宣传部、杂志社、科研处联合主办了“有效降低全社会物流成本”研讨会。本次研讨会邀请我国流通物流领域的专家学者,围绕物流服务实体经济和人民群众、物流成本构成、交通运输体系改革、统一高效物流市场构建和现代商贸流通体系完善等问题,发表观点,为探索有效降低全社会物流成本可行路径,构建现代流通体系提供理论支持和实践指导。本刊编辑部对专家阐述的主要观点进行了归纳整理,以飨读者。

关键词：全社会社会物流成本新质生产力流通体系降本增效