اختيار مواقع لإنشاء سدود صغيرة في منخفض الكعرة باستخدام تقنيات التحسس النائي والتحليل المكاني

Abstract

Feature extraction from the surface topography is the creation of a bitmap representing the earth's surface elevations based on Digital Elevation Model, which is the base of the analyzing of topographical surfaces. The digital elevation models are mainly derived by stereo pair images (a pair of images) available from the Photogrammetry data and remote sensing, or from topographical maps, and we use a digital elevation model derived from topographical maps, and we derived a number of important properties from digital elevations model such as gradient direction and the Earth's shadow using a ArcGIS ver. 9.3 , which represent the input data to extract the hydrological characteristics such as determining the flow direction , also calculating the flow accumulation , producing the output map Stream to determine the valleys in the region and the production of Basin map to determine the basin of nutrition , the locations of the small dams can be selected using Arc GIS ver. 9.3 and its extension Arc Hydro.