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排序方式: 共有3593条查询结果,搜索用时 15 毫秒
1.
试论新世纪地理信息科学的发展 总被引:1,自引:0,他引:1
本文重点分析了当前国内外地理信息科学的形成与发展趋势和地理信息科学不断发展的历程 ,提出近期发展的前沿 ,以及当前地理信息产业化面临的一些重要问题。最后提出对地理信息科学发展的意见。 相似文献
2.
T.-C. Jim Yeh 《水文研究》1992,6(4):369-395
This paper presents an introductory overview of recently developed stochastic theories for tackling spatial variability problems in predicting groundwater flow and solute transport. Advantages and limitations of the theories are discussed. Lastly, strategies based on the stochastic approaches to predict solute transport in aquifers are recommended. 相似文献
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严格论证了在对空间或地面目标的定位中,利用伪距测量观测模型的几何因子大于用台站间一次差分观测模型的几何因子.此外,台站间完全差分测量观测的定位精度优于不完全测量情形的定位精度.这些结果给人们在实际工作中采取何种定位方式提供了可靠的理论依据. 相似文献
6.
Galileo系统及其在中国的应用 总被引:9,自引:0,他引:9
较详细地介绍了Galileo系统的全面体系结构、频率设计、服务内容及其广泛的应用范围,指出了它与GPS系统相比的优点,并对开发和增强Galileo系统在我国多层次、全方位的应用提出了建议。 相似文献
7.
Atlas of karst area based on Web GIS technology 总被引:1,自引:0,他引:1
Leszek Litwin 《Environmental Geology》2008,54(5):1029-1036
8.
Development of a 3D GIS and its application to karst areas 总被引:1,自引:0,他引:1
There is a growing interest in modeling and analyzing karst phenomena in three dimensions. This paper integrates geology,
groundwater hydrology, geographic information system (GIS), database management system (DBMS), visualization and data mining
to study karst features in Huaibei, China. The 3D geo-objects retrieved from the karst area are analyzed and mapped into different
abstract levels. The spatial relationships among the objects are constructed by a dual-linker. The shapes of the 3D objects
and the topological models with attributes are stored and maintained in the DBMS. Spatial analysis was then used to integrate
the data in the DBMS and the 3D model to form a virtual reality (VR) to provide analytical functions such as distribution
analysis, correlation query, and probability assessment. The research successfully implements 3D modeling and analyses in
the karst area, and meanwhile provides an efficient tool for government policy-makers to set out restrictions on water resource
development in the area. 相似文献
9.
R. K. Prasad N. C. Mondal Pallavi Banerjee M. V. Nandakumar V. S. Singh 《Environmental Geology》2008,55(3):467-475
Remote Sensing and Geographic Information System has become one of the leading tools in the field of hydrogeological science,
which helps in assessing, monitoring and conserving groundwater resources. It allows manipulation and analysis of individual
layer of spatial data. It is used for analysing and modelling the interrelationship between the layers. This paper mainly
deals with the integrated approach of Remote Sensing and geographical information system (GIS) to delineate groundwater potential
zones in hard rock terrain. The remotely sensed data at the scale of 1:50,000 and topographical information from available
maps, have been used for the preparation of ground water prospective map by integrating geology, geomorphology, slope, drainage-density
and lineaments map of the study area. Further, the data on yield of aquifer, as observed from existing bore wells in the area,
has been used to validate the groundwater potential map. The final result depicts the favourable prospective zones in the
study area and can be helpful in better planning and management of groundwater resources especially in hard rock terrains. 相似文献
10.
Spatial data for landslide susceptibility, hazard, and vulnerability assessment: An overview 总被引:30,自引:0,他引:30
The aim of this paper is to discuss a number of issues related to the use of spatial information for landslide susceptibility, hazard, and vulnerability assessment. The paper centers around the types of spatial data needed for each of these components, and the methods for obtaining them. A number of concepts are illustrated using an extensive spatial data set for the city of Tegucigalpa in Honduras. The paper intends to supplement the information given in the “Guidelines for Landslide Susceptibility, Hazard and Risk Zoning for Land Use Planning” by the Joint ISSMGE, ISRM and IAEG Technical Committee on Landslides and Engineered Slopes (JTC-1). The last few decades have shown a very fast development in the application of digital tools such as Geographic Information Systems, Digital Image Processing, Digital Photogrammetry and Global Positioning Systems. Landslide inventory databases are becoming available to more countries and several are now also available through the internet. A comprehensive landslide inventory is a must in order to be able to quantify both landslide hazard and risk. With respect to the environmental factors used in landslide hazard assessment, there is a tendency to utilize those data layers that are easily obtainable from Digital Elevation Models and satellite imagery, whereas less emphasis is on those data layers that require detailed field investigations. A review is given of the trends in collecting spatial information on environmental factors with a focus on Digital Elevation Models, geology and soils, geomorphology, land use and elements at risk. 相似文献