With the rapid development of Earth observation technologies, raster data has become the main Geographic Information System (GIS) data source. GIS should be able to manage and process huge raster data sets. In this paper, the problem of 3-dimensional visualization of huge DEM data sets and its corresponding image data sets in GIS was addressed. A real-time delamination method based on raster ch...

SAR Interferometry (InSAR) provides data that contain information relating to the phase and coherence components of the backscattered radar signals. Phase information is used to derive Digital Elevation Models (DEM). This paper presents the results of an analysis of the accuracy of InSAR DEM derived from ESAR L-band airborne repeat-pass fully polarimetric InSAR data, which were acquired over Th...

the aim of the study is the classification of landform based on elevation, slope, relief and curvature inputs (old method) and topographic position index (tpi) (new method) in the south of bojnoord. the input data for the two methods is a digital elevation model (dem). the results of topographic position index (tpi) model showed that most area of landform were covered by class 5 (plains small) ...

Information about the shape of the Earth’s surface is important in many applications as it helps users to visualize and analyze geographic problems accurately in 3D. This paper focuses on the InSAR technique of generating Digital Elevation Models (DEM) by using InSAR data acquired from an airborne platform. The data cover a study area of 4 km x 3 km located in Thetford Forest, East Anglia, Unit...

Algorithms are presented which use a digital elevation model (DEM) to extract topographic patterns. The algorithms have been applied to extracting natural topographic automatically from the regular grid DEM of a testing area. The experimental results have proved that the automatic extracting algorithms are effective.

Topography is a crucial surface characteristic in soil erosion modeling. Soil erosion studies use a digital elevation model (DEM) to derive the topographical characteristics of a study area. Majority of the times, a DEM is incorporated into erosion models as a given parameter and it is not tested as extensively as are the parameters related to soil, land-use and climate. This study compares ero...

Coastal managers require reliable spatial data on the extent and timing of potential coastal inundation, particularly in a changing climate. Most sea level rise (SLR) vulnerability assessments are undertaken using the easily implemented bathtub approach, where areas adjacent to the sea and below a given elevation are mapped using a deterministic line dividing potentially inundated from dry area...

This paper describes a new fast and scalable parallel algorithm to compute global flow accumulation for automatic drainage network extraction in large digital elevation models (DEM for short). Our method uses the D8 model to compute the flow directions for all pixels in the DEM (except NODATA and oceans). A parallel spanning tree algorithm is proposed to compute hierarchical catchment basins to...

The digital elevation model derived from SAR Interferometry is prone to atmospheric, penetration into soil medium, system noise and decorrelation errors. Eight ASAR images are selected for this study which have unique data set forming 7 InSAR pairs with single master image. It is expected that all the DEMs should have the same elevation values spatially with in the noise limits. However, they d...