Users of GIS are faced with the ongoing and difficult problem of estimating the validity of a GIS output given the uncertainty of the quality of cLgital mapped data. This research project examines the manner in which error from a digital elevation model (DEM) results in error in an estimate of a viewshed. The data set includes two DEMs for the same study area. A 10-metre DEM serves as the contr...

* Corresponding author. E-mail address: [email protected] (B. 1537-5110/$ – see front matter a 2008 IAgrE doi:10.1016/j.biosystemseng.2008.09.010 Digital Elevation Model (DEM) fusion was investigated for improving the overall accuracy of DEMs. The approach was applied to two public domain products: Shuttle Radar Topographic Mission (SRTM) DEM and Advanced Spaceborne Thermal Emission and Refl...

One of the biggest problems faced while analyzing digital elevation models (DEMs), particularly DEMs that are produced using photogrammetry, is to avoid pits and peaks in DEMs. Peaks and pits, which are errors, are generated during the surface generation process. DEM smoothening is an important preprocessing step meant for removing these errors. This paper discusses two linear DEM smoothening m...

Very little work has been done on the systematic evaluation of effect of compression on the accuracy of DEM derived using satellites imageries. Most of studies have been carried out for aerial images and models have been developed which relate DEM accuracy with compression. One such model predicts effect of compression on DEM accuracy as 0.2% of flight height for CR up to 15:1 but these models ...

digital elevation model (dem) is increasingly used these days as an effective tool to extract elevation data in quantitative environmental and land management studies. the improvement of sensors and land resource satellites has made it possible to generate dem from remotely sensed data. dems which are produced from these data are applied not only in the two dimensional (2d) but also in the thre...

BACKGROUND Few personalized e-interventions are available for informal and professional caregivers of people with dementia. The DEMentia Digital Interactive Social Chart (DEM-DISC) is an ICT tool to support customized disease management in dementia. The aim of this study was to improve and evaluate DEM-DISC, its user-friendliness and usefulness and to investigate the future implementation. ME...

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...