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21.
城市建设出现了地形图图式未规定的地物要素,地形测量、地理信息系统、数字制图技术的应用给图式的设计提出了新的课题,本文旨在探讨设计和修订图式的思路和方法。 相似文献
22.
Validation of Landslide Susceptibility Maps; Examples and Applications from a Case Study in Northern Spain 总被引:9,自引:3,他引:9
Remondo Juan González Alberto De Terán José Ramón Díaz Cendrero Antonio Fabbri Andrea Chung Chang-Jo F. 《Natural Hazards》2003,30(3):437-449
A procedure for validating landslide susceptibility maps wasapplied in a study area in northern Spain and the results obtained compared. Validationwas used to carry out sensitivity analysis for individual variables and combinationsof variables. The validity of different map-making methods was tested, as well as theutility of different types of Favourability Functions. The results obtained show thatvalidation is essential to determine the predictive value of susceptibility maps. Italso helps to better select the most suitable function and significant variables, thus improving the efficiency of the mapping process. Validation based on a temporal strategy makes it possible to derive hazard maps from susceptibility maps. 相似文献
23.
用历史数据库实现对GIS时态属性的管理 总被引:4,自引:0,他引:4
从有效管理GIS时态属性数据的目的出发,设计了一个历史数据库系统,详细 了时态属性以及它的更新操作规则,并提供了历史关系的5种基本运算和历史查询语言。 相似文献
24.
在地图内容和形式数学表示的基础上研究了地图的数学定义。由于引入隐式地图和变换条件,故所有储存地图信息的载体均可属于地图的范围,从而使地图定义获得了广义的解释和精确的表达 相似文献
25.
26.
Walter Lorenz 《Natural Resources Research》1997,6(1):5-10
For those who deal with aspects of regional planning that are affected by the extraction of near-surface mineral resources,
a simple map that shows the distribution of these resources accompanied by explanatory notes is essential; a preliminary 1:1
million-scale map was published in 1982. The Geological Surveys of the Federal States of Germany, in conjunction with the
Federal Institute for Geosciences and Natural Resources, are compiling a series of maps that will cover the country at a scale
of 1:200,000. When completed by the end of the next decade, this set of maps will consist of 57 sheets, each of which will
be accompanied by explanatory notes. By the end of 1995, 17 sheets had been published
BGR reports on the status of a Federal mineral-resource mapping program. 相似文献
27.
Management of Historical Seismic Data Using GIS: The Island of Ischia (Southern Italy) 总被引:1,自引:0,他引:1
This paper presents the results of the use of Geographic Information Systems (GIS) inmanaging information on the effects of earthquakes in historical times on the island ofIschia. The unpublished sources on the Casamicciola earthquake of 28 July 1883 andthe extensive bibliography documenting the island's seismicity from 1228 showed theneed to proceed towards a type of data storage that would also allow management ofthe same data. Application of GIS techniques allowed us to insert, extract, handle,manage and analyse the data for the zoning of seismic damage on the island of Ischia.The end-product consists of information layers, such as maps of isoseismals, the damage, and hazard involved, as well as numerical tables associated to maps.The study was developed using GIS Arc-View 3.2 software (ESRI) and is structured inthematic vectorial levels and rasters. The overlapping themes constitute a cartographicdata base of the island. The damaged sites are located on a map at a scale of 1:10,000,with all the information on the 1883 earthquake (total number of houses, number ofcollapsed houses, collapsed or damaged rooms, photographs, plans of buildings, etc.)being associated to each site. The GIS is structured in such a way as to be able to beintegrated with further georeferenced data and with other databases. It is thus able toprovide support both for in-depth analyses of the dynamic processes on the island andextend the assessment to other natural risks (volcanic, landslides, flooding, etc.). 相似文献
28.
The relative importance of the contribution of the lower crust and of the lithospheric mantle to the total strength of the continental lithosphere is assessed systematically for realistic ranges of layer thickness, composition, and temperature. Results are presented as relative strength maps, giving the ratio of the lower crust to upper mantle contribution in terms of crustal thickness and surface heat flow. The lithosphere shows a “jelly sandwich” rheological layering for low surface heat flow, thin to average crustal thickness, and felsic or wet mafic lower crustal compositions. On the other hand, most of the total strength resides in the seismogenic crust in regions of high surface heat flow, crust of any thickness, and dry mafic lower crustal composition. 相似文献
29.
30.
山西大同-阳高地震活动背景 总被引:2,自引:1,他引:2
通过对大同盆地历史地震活动及大同盆地历史地震活动与华北地震区、山西地震带强震活动的关系的研究,得出山西大同-阳高1989年6.1级地震活动是这一地区历史地震的延续,是华北北部中强地震活动的重要组成部分,具有广义前震的重要意义,其后对应发生的河北张北6.2级地震。标志着华北地震区的地震活动期已进入尾声。 相似文献