تقييم دقة نماذج الارتفاعات الرقمية العالمية من بيانات المساحة الجوية (دراسة مقارنة بين مناسيب خريطة طبوغرافية وملفات DEMنوع SRTM1لمدينة الكفرة

الملخص

The aim of this study is to evaluate the accuracy of the levels of global digital elevation files deduced from the models of global digital elevation files DEM type (SRTM 1) for the study area located in southeastern Libya (the city of Kufra and its suburbs) by comparing them with high accuracy measurements of the helmet from an old topographic map produced in 1975 by the German Group for Water Engineering using aerial photography for the Agricultural

Development Council and under the supervision of the Libyan Survey Department with a total area of (125 km ×125 km) for the area, after being numbered with a scanner, where the ground control points in the aerial map were 350 control points with a spatial clarity of approximately 17 meters for the topographic map used.

Four Global Digital Elevation (DEM) models covering the study area were used to compare these models with the topographic map used from aerial photography of the area.

It is also known that the topographic survey mission of the radar shuttle (SRTM 1) is an abbreviation of the word Shuttle Radar Topography Mission is the acquisition of global digital altitude models around the Earth to be made available free of charge for three-dimensional modeling, environmental and other applications. These data provide a baseline of information that can be used in spatial applications such as hydrological mapping, navigation, reconnaissance surveys and preliminary studies of engineering projects.

The quality of this data produced was also evaluated through a number of comparisons with the values of contour lines from topographic maps and from field investigation points. Maps representing the topography and surfaces of the numerical model were also produced, the quantities of excavation and backfill required to level the site for one level were calculated, and standard deviation, arithmetic mean and mode were calculated.