Techniques to Generate Digital Elevation Model (DEM)

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Techniques to Generate Digital Elevation Model
(DEM)
A Digital Elevation Model is a bare-earth raster
grid referenced to a vertical datu 1. Ground
Survey Techniques Ground Survey Techniques are
the most widely
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1. Existing Topographic Maps Topography is one of
   the major factors in most types of hazard a
2. Stereo Photogrammetry For both aerial
   photography and satellite imagery, photogrammetry

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4. Stereoscopic 3-D images (aerial photos,
optical satellite images) Various optical
satellite sen
5. RADAR DEMs are also available using radar
satellites such as RADARSAT, TerraSAR-X, ALOS PAL
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1. Airborne Laser Scanning (LiDAR) The most
   detailed DEMs today are available using LiDAR.
   Usu
2. DGPS measurements GPS or DGPS, people conduct
   field campaigns with special devices that us
3. Digital contour lines Use of contour maps, DTMs
   (DEM subset) can be easily digitized and inter

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9. Spatial Interpolation Spatial Interpolation
uses known value points to estimate values ??in
oth Major Types of Spatial Interpolation IDW I
DW is an exact interpolation because it is based
on weightage, the weightage of each sample poi
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Kriging
Kriging is a geospatial method for spatial
interpolation. It predicts the quality of
predictio Spline The Spline tool estimates the
values ??using a mathematical function that
reduces the ov
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How is Satpalda Contributing to DEM?
SATPALDA provides high-resolution elevation
data. It contains locations with
elevations Satellite image Orthorectification
Military and civil aviation Management of oil
and gas fields Defence and security related
missions Watershed analysis