电子地图中居民地的多尺度显示     

宋国民贾奋励  王光霞 《测绘学院学报》2004,21(1):57-60

探讨了多尺度的含义，并将居民地多尺度表达的研究限定在详细程度的变化上；阐述了电子地图中居民地多尺度表达的基本原理，即在保持原图的分布特征和疏密对比的情况下按照居民地自身的分类分级和重要性程度进行一定数量的取舍；建立了居民地多尺度显示的模型，根据此模型提出了采用二级邻近点判别法结合Voronoi图进行居民地要素的显示等级设置的方法，并进行了相应的实验，结果表明该方法对居民地的分布特征、密度对比和延伸方向均能较好的保持。  相似文献   

Landslide Susceptibility Zoning North of Yenice (NW Turkey) by Multivariate Statistical Techniques   总被引：4，自引：1，他引：4  

M. Ercanoglu  C. Gokceoglu  Th. W. J. Van Asch 《Natural Hazards》2004,32(1):1-23

Dramatic effects resulting from landslides on human life and economy of many nations are observed sometimes throughout the world. Landslide inventory and susceptibility mapping studies are accepted as the first stage of landslide hazard mitigation efforts. Generally, these landslide inventory studies include identification and location of landslides. The main benefit is to provide a basis for statistical susceptibility zoning studies. In the present study, a landslide susceptibility zoning near Yenice (NW Turkey) is carried out using the factor analysis approach. The study area is approximately 64 km² and 57 landslides were identified in this area. The area is covered completely by Ulus Formation that has a flysh-like character. Slope angle, elevation, slope aspect, land-use, weathering depth and water conditions were considered as the main conditioning factors while the heavy precipitation is the main trigger for landsliding. According to the results of factor analysis, the importance weights for slope angle, land-use, elevation, dip direction, water conditions and weathering depth were determined as 45.2%, 22.4%, 12.5%, 8.8%, 8.1% and 3.0% respectively. Also, using these weights and the membership values of each conditioning factor, the membership value for landslide susceptibility was introduced. In the study area, the lowest membership value for landslide susceptibility was calculated as 0.20. Consequently, combining all results, a landslide susceptibility map was obtained. Compared with the obtained map, a great majority of the landslides (86 %) identified in the field were found to be located in susceptible and highly susceptible zones.  相似文献   

中国1∶400万沼泽图的编制研究     

王化群 《湿地科学》2004,(1)

中国 1∶4 0 0万沼泽图是我国第一幅大范围的沼泽图件。本图及其附图以地图图像的形式 ,形象地、系统地总结和反映了我国有关单位近 4 0年来在沼泽方面的研究成果 ,表现了我国及主要典型区的沼泽及诏泽化土地的类型、特征、形成及其分布规律。重点反映适合我国沼泽特点并具有新观点的分类体系和分区体系。全国沼泽分类体系被分为四级 :类 (第一级 )、亚类 (第二级 )、型 (第三级 )、组 (第四级 )。全国沼泽化土地的分类系统也相应分为四级。主图表示沼泽和沼泽化土地的前三级类型 ,在作为插图 (2幅 )和附图 (4幅 )的典型区沼泽图 (1∶2 0万～ 1∶15 0万 )上侧重表示第四级类型。另一幅插图为《中国沼泽分区图》(1∶2 5 0 0万 ) ,全国被分为 8个沼泽区和 4 0个沼泽亚区。中国 1∶4 0 0万沼泽图采用综合图型 ,范围法与符号法 (分级定位符号 )相结合的表现方法 ,室内制图资料综合分析利用与野外验正和缩编相结合的编绘方法。  相似文献   

Cause-Effect Analysis in Assessment of Mineral Resources   总被引：1，自引：0，他引：1  

Sirotinskaya  Susanna V. 《Natural Resources Research》2004,13(1):17-28

Cause-effect analyses is a deterministic methodology intended for processing qualitative (e.g. texts, conventional maps) and mixed, qualitative and quantitative, data. The main idea, employed in cause-effect analysis, is the plurality and interaction of causes. This idea is described by mathematical logic formulae that can be converted into a single Boolean equation. The latter represents a mathematical model of a general shape of cause-effect relations for the study problem. In particular, such a model can express relations between some property of the mineralization and features of other geological phenomena. By processing data, logical dependencies satisfying to the theoretical model are determined in a data file. These dependences, expressed by Boolean function formulae, describe cause-effect relations for a case study, and they are used for predicting. Software realizing the cause-effect analysis is an expert system with artificial intelligence capabilities. There are two methods of using the cause-effect analysis in assessment of mineral resources. The first method consists in detecting the regularity in locations of known mineral deposits and occurrences with the following using the regularity formula for generation of predictive maps. The second method is the evaluation of individual mineral occurrences by obtained Boolean formulae expressing cause-effect relations between deposit sizes and geological environment of deposits. Both methods are illustrated by case studies of predicting gold-bearing deposits of Middle Asia in the former USSR.  相似文献   

TIN模型在地球化学勘查的计算机辅助制图中的研究和应用     

卢社香  崔来运  丁汉铎 《矿产与地质》2004,18(6):604-608

以济源西北部 1∶ 5 0 0 0 0水系沉积物测量和嵩县小南沟金矿区地球化学勘查两个项目为实例 ,总结了 TIN模型在区域化探扫面和矿区化探剖面的辅助制图中的应用特点及需注意的问题 ,着重介绍了数据布局方法和调整 Delaunay三角剖分网技术 ,对在不规则采样区域边界带圈等值线的形状问题 ,首次采用虚设采样点的方法进行处理 ,取得了很好效果  相似文献   

Landslide incidence zonation in the Rio Mendoza valley,Mendoza Province,Argentina     

Stella M. Moreiras 《地球表面变化过程与地形》2004,29(2):255-266

This paper presents a landslide incidence zonation map showing the percentage of underlying material involved in mass‐movement processes in the Rio Mendoza valley, Argentina. The landslide incidence zonation map was derived from an inventory map of landslides and reveals that many areas of the Rio Mendoza valley are implicated in this kind of process. A correlation has been found between the occurrence of landslides, earthquakes, and rainfall. The relation between lithology and landslides is clear: areas covered by friable sedimentary and volcanic rocks of the Choiyoi Group are prone to debris ?ows and complex landslides. The slope map has been ranked and a general relation between slope and type of event is shown. Falls commonly develop in high‐angle slopes. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

LANDSLIDE POTENTIALITY OF THE TSENGWEN RESERVOIR WATERSHED, TAIWAN     

Chin-yu LEE Professor  Department of Soil  Water Conservation  National Pingtung University of Science  Technology  Pingtung    Taiwan  R.O.C. 《国际泥沙研究》2004,(2)

To recognize the geographical characteristics of the landslide areas will be helpful for the watershedmanagement in the reservoir watershed. According to the quantitative analysis, we'll take differentscores and weighting for the potential parameters of the landslide areas in the Tsengwen reservoirwatershed, and in the meanwhile, we'll extract the different factors, including the slope, aspect,altitude, soil and geological textures etc., and the results shown as maximum one--day rainfall, ratio offorests and average relief is the most affecting parameters on the potential risk map of landslide areas.  相似文献   

Self-organizing feature map neural network classification of the ASTER data based on wavelet fusion   总被引：3，自引：0，他引：3  

HASI Bagan  MA Jianwen  LI Qiqing  HAN Xiuzhen & LIU Zhili Laboratory of Remote Sensing Information Science  Institute of Remote Sensing Applications  Chinese Academy of Sciences  Beijing  China 《中国科学D辑(英文版)》2004,47(7):651-658

Remote sensing classification methods can be classified as supervised and unsupervised catalogs. The maximum likelihood method (MLH) is a super-vised classification method,which is widely used in the remote sensing data classification and produces good results[1]. In the MLH, the parameters are esti-mated, assuming that the samples are normally dis-tributed in spectral space, to determine the mean vec-tor and covariance matrix of all classes. In most cases, however, the samples are not norma…  相似文献   

直接写位图实现探地雷达数据显示研究     

陈越刘庆成  吴信民张志勇 杨亚新 《华东地质学院学报》2004,27(3):265-267

有效提高探地雷达(简称GPR)数据的色谱显示速度是GPR软件开发的一个重要项目。由文件头、位图信息头加住图数据组的BMP住图记录格式与由文件头加道数据组成GPR数据记录格式有很强的相似性。本文利用这种相似性，提出了一种有效提高GPR数据显示速度的方法。该方法利用文件头和必要的文件信息生成住图信息，然后完成GPR数据到住图数据的变换，最后通过住图的显示来完成GPR数据的显示。这种方法减少了对磁盘的访问次数，数据变换在内存中完成，数据显示一次完成所以有效提高了数据的显示速度。  相似文献   

区域电子地图工程设计模式研究   总被引：3，自引：0，他引：3  

任福  杜清运  蔡忠亮 《武汉大学学报(信息科学版)》2005,30(4):301-304

在大量实践的基础上，总结并设计了一种任务驱动型工程建设模式，以便使新系统开发者更容易理解其设计思路，作出有利于系统复用的选择，最终为同类实践活动提供可操作的参考方案。  相似文献