There are many kinds of DEM (Digital Elevation Model) generation methods such as a stereomatching from aerial photograph or satellite image, an interferometry from SAR data and an interpolation of topographic maps. On the other hand, we can use some accomplished DEMs. For example, NGDC NOAA offers global land one-km base elevation (GLOBE). And USGS offers Digital Chart of the World that has ele...

In this work, a new partition-collocation strategy for the parallel execution of CFD–DEM couplings is investigated. Having a good parallel performance is a key issue for an Eulerian-Lagrangian software that aims to be applied to solve industrially significant problems, as the computational cost of these couplings is one of their main drawback. The approach presented here consists in co-locating...

Digital Elevation Model (DEM) is an important input for geo-spatial analysis. For various applications like flood management, ortho rectification of remote sensing images, navigation, architectural works, defence, etc., high resolution DEM is required. TanDEM-X mission was launched in 2010 to obtain high resolution global DEM with HTRI-3 standard. SAR interferometry (InSAR) technique is used fo...

preparation of the topographic factor (ls) map in rusle model is a very tedious step because of the complicated effects of topography on soil loss. the objective of this study was to determine the suitable cell size of digital elevation model (dem) for computing ls factor by the method of moore and wilson (1992) in a 5326 ha area, northwest of tehran province. towards this end, cell sizes of 30...

Assessment of a DEM’s quality is usually undertaken by deriving a measure of DEM accuracy – how close the DEM’s elevation values are to the true elevation. Measures such as Root Mean Squared Error and standard deviation of the error are frequently used. These measures summarise elevation errors in a DEM as a single value. A more detailed description of DEM accuracy would allow better understand...

McClure, A.; Liu, X.-H.; Hines, E., and Ferner, M.C., 0000. Evaluation of error reduction techniques on a LIDAR-derived salt marsh digital elevation model. Journal of Coastal Research, 00(0), 000–000. Coconut Creek (Florida), ISSN 07490208. Accurate elevation information is a necessity for conservation and management of tidal salt marshes where elevation differences can be as little as 2 m and ...

This paper proposes the localization algorithm that estimates translation parameters of an aircraft by comparing the sampled elevation map recovered from aerial sequence images, and the digital elevation model (DEM) with the given orientation and altitude parameters obtained from a gyroscope. It consists of two stages: recovering the sampled elevation map from multiple aerial image pairs and ma...

Aerial photographs and satellite imagery have been evaluated manually by the operators for a long time for the extraction of the contour line and DEM data. Computer technology and digital image processing technologies have been developed and this development provides to perform these extraction processes automatically or semi-automatically. The aim of making the processes automatic is to increa...

Soil Salinity has been a large problem in arid and semi arid regions. Preparation of such maps is useful for Natural resource managers. Old methods of preparing such maps require a lot of time and cost. Multi-spectral remotely sensed dates due to the broad vision and repeating of these imageries is suitable for provide saline soil maps. This investigation is conducted to provide saline soil map...

The aim of this tutorial is to show how to easily create a Digital Elevation Model (DEM) and orthorectified image from free ASTER satellite imagery. PCI Geomatica OrthoEngine is the software package used to perform the processing. The imagery used in this tutorial is from Southern Scotland, around Loch Doon in the United Kingdom. These web sites provide contextual pictures of the area….