At present, computers, lasers, radars, planes and satellite technologies make possible very fast and accurate topographic data acquisition for the production of maps. However, the problem of managing and manipulating this data efficiently remains. One particular type of map is the elevation map. When stored on a computer, it is often referred to as a Digital Elevation Model (DEM). A DEM is usua...

The digital elevation model (DEM) is the name given to a structure used indicate surface. Determination of features such as elevation, basin slope and area are very important in engineering applications. These properties determined by DEM their power represent accuracy or truth vital In addition latitude (X), longitude(Y) coordinate information, altitude information required, intermediate value...

Introduction The application of geographic information systems (GISs) to natural hazard risk management is a relatively new and emerging science. Coppock (1995) notes that GIS has made a contribution to various facets of natural hazard risk management since risk is a multi-dimensional and multidisciplinary phenomenon, which have a spatial component, whatever their initial focus. Hence, the succ...

Under increased urban settlement density, access to a high resolution (land-parcel scale) bare-earth Digital Elevation Model (DEM) is a pre-requisite for much decision support for planning: stormwater assessment, flood control, 3D visualisation, automatic delineation of flow paths, sub watersheds and flow networks for hydrological modelling. In these terms, a range of options face the DEM-build...

Digital Elevation Model (DEM) is a kind of method and means describing three-dimension terrain visualization in computer graphics and visualization. However, there are plenty of redundant data in DEM that is described by grid or TIN (triangulated Irregular Network). The main content of this paper is the study about 3D surface simplification in terrain visualization model based on triangulated n...

A new digital elevation model (DEM) is presented for accurate surface representation in photogrammetric processing of stereo ground-based imagery. This model is named the continuative variable resolution DEM (cvrDEM). In contrast to traditional grid-based DEMs that have only one fixed resolution, this new model can provide resolutions that vary depending on the range represented in the groundba...

In order to assess the impact of natural and anthropogenic stresses on forest ecosystems, it is necessary to interpolate air temperature and tropospheric ozone (O3) exposure values at high spatial resolution over complex terrain. The proposed interpolation approach was selected because of its ability to (1) account for the effect of elevation on temperature and their effects on tropospheric ozo...

The block adjustment method can correct systematic errors in the bistatic Synthetic Aperture Radar Interferometry (InSAR) satellite system and effectively improve accuracy of InSAR-generated Digital Elevation Model (DEM). Presently, non-parametric methods, which use polynomial to model DEMs, are most frequently used spaceborne InSAR-DEM adjustment. However, methods not directly related physical...

The launch of ERS-l provides coverage, by satellite altimetry, of 80% of the Antarctic ice sheet, allowing topographic mapping of areas which previously had a dearth of accurate elevation data. Four 35 d repeat cycles of fastdelivery altimeter data were used in this study, comprising a total of approximately 1000000 height estimates. About 40% of these were rejected during a careful filtering p...

Number: 11 User Lastname: Adam User Firstname: Nico User e-mail: [email protected] Affiliation: German Aerospace CenterGerman Remote Sensing Data Center User Address: German Aerospace CenterGerman Remote Sensing Data CenterOberpfaffenhofen User Telephone: +49 8153 281326 User Fax: +49 8153 281446 Theme: Topographic Mapping and Digital Elevation Models Special Requirements: User Type: Presenter (v...