利用Kullback-Laible信息量的空间数据几何纠正模型选择

由于地图数字化数据在采集和制图过程中存在系统误差的影响,导致其空间位置精度较低。在实测较高精度的GPS控制点的基础上,基于Kullback-Laible(KL)信息量改进的赤池信息标准(AICc)来选择最佳的转换模型,实现地图数字化数据的几何纠正,从而达到提高其位置精度的目的。     

地图扫描数字化中的图形纠正

地图扫描数字化是GIS数据采集的重要手段，地图上的图形经扫描数字化后，其几何形状和面积因误差的存在而发生改变。文中利用几何纠正与面积会合的方法建立数字化点的误差模型，并根据解算结果对GIS中的图形进行纠正，使数字化的图形面积与实测面积相一致，以满足土地管理及城市规划等部门的需要。     

浅析扫描地形图纠正方法与常用地图纠正软件的使用

主要介绍了图像数字化原理,扫描地形图纠正原理和常用地形图纠正软件的使用方法。     

基于总体最小二乘的相似变换模型及其在地图扫描数字化中的应用

在地图扫描数字化中,图纸定向的精度直接影响后续地图要素数字化的精度,而在图纸定向中较为常用的相似变换模型未能周全考虑地图定向点的采集误差以及原始地理坐标的测量误差。引进总体最小二乘方法,建立基于总体最小二乘的相似变换模型,结合地图扫描数字化实验,分析基于总体最小二乘方法的相似变换模型的适用性及优越性。     

数字科普馆建设对防震减灾科普宣传的启示——以海南省地震局防震减灾数字科普馆为例

随着数字化技术的发展和互联网的普及,互联网+防震减灾科普已成为实现防震减灾科普社会化的最有效途径。数字地震科普馆作为计算机技术发展的产物,在更深更广的时空范围内进行地震知识的普及,能够极大地提高地震科普宣传的质量和效率。本文以海南省地震局防震减灾数字科普馆为例,介绍其构建及实现技术,说明其应用情况,探讨了数字科普馆对防震减灾科普宣传的启示及其对未来宣传防震减灾科学知识的促进作用。     

扫描数字化地图数据的误差分析及控制

分析了基于扫描数字化GIS数据生产过程中的误差来源,针对各种误差提出了质量控制方法和一些质量控制指标,并结合实例作了精度分析。可以为地图扫描数字化减小误差、进行质量控制提供一定的借鉴。     

Common problems in automatic digitization of strong motion accelerograms

Common problems encountered in automatic digitization of strong motion accelerograms, recorded on film, are presented and discussed. These include synchronization of the time scale for the three components of motion, non-uniform film speed, trace following in case of scratches or trace crossings, distortions from high contrast preprocessing of the scanned image, and trace “rotation” resulting from rotated position of the scanned film record. Procedures for correcting or eliminating these problems are suggested. The image processing hardware has developed so much during the past 20 years, that at present it exceeds the technical requirements for processing strong motion accelerograms. The problems described in this paper result from lack of training of the operators and lack of quality control in the process, which still seems to be esoteric and highly specialized. This situation may have been caused by the low demand by the engineering profession for high quality and large volume of strong motion data.     

厦门市地震遥测台网监测能力检验

通过对厦门台网实测资料的分析,检验了台网的监测能力。认为距中心１００￣１５０ｋｍ发生的大于ＭＬ２．５地震和距中心４５０ｋｍ内（包括台湾东带）发生的大于ＭＬ３．５地震处于该台网有产监测范围内。     

The scheme for the database building and updating of 1∶10 000 digital elevation models

［1］Balce A E. Determination of optimum sampling interval in grid digital elevation models (DEM) data acquisition.Photogrammetric Engineering and Remote Sensing,1987,531:323～330 ［2］Li Z L. Sampling strategy and accuracy assessment for digital terrain modelling: [Ph. D Thesis]. UK: University of Glasgow, 1990 ［3］Li Z L. Variation of the accuracy of digital terrain models with sampling interval. Photogrammetric Record, 1992,14:113～128 ［4］Li Z L. A comparative study of the accuracy of digital terrain models(DTMs) based on various data models. ISPRS Journal of Photogrammetry and Renote Sensing,1994,49(1):2～11 ［5］Li Z L. Scale issues in geographic information science. In:Proceeding of International Workshop on Dynamic and Multi-dimensional GIS. Hong Kong, 1997. 143～158 ［6］SISM. Specification of geospatial data (Provisional) for 1:10 000 digital elevation models. The Standard Institute of Surveying and Mapping (SISM), National Bureau of Surveying and Mapping, China, 1997(in Chinese) ［7］USGS. National Mapping Program: Geospatial Data Standard, 1992 ［8］Zhu Q, Cheng C J. The fast generation and dynamic updating of TIN. Journal of Wuhan Technical University of Surveying and Mapping, 1998(in Chinese)     

区域化探室内工作方法的探讨

利用计算机技术对区域化探室内工作方法进行改进,可以减轻劳动强度,省去大量的手工操作环节和工作量,提高工作效率和质量,使区域化探工作上一个新台阶。