الفهرس 
Geodetic Datums (Reference Ellipsoids) and AssociatedOnly 14 pages are availabe for public view
 |  | from | 203 |  |  |
| | | from | 203 | | |
Abstract
Geodetic control networks are the main frames of all surveying and mapping works for any country, such as Egypt, to which surveying and mapping works as well as engineering projects and utilities are connected in a unified national coordinate system. The basic Egyptian geodetic control networks were established early in the 20th century, using classical terrestrial technique, relative to the Egyptian Geodetic Datum (EGD). Such networks cover mainly the North coast, the Nile valley, the Red Sea coast, and some parts of Sinai region, while other remaining regions are lacking such geodetic control.
In addition, one should be certain that the geodetic framework should be accurate enough for the recent requirements of geodetic accuracy standards and associated applications. Of course, the use of traditional terrestrial positioning techniques for such purpose will be cost and time consuming besides its associated troublesome.
Instead, the modern space techniques using artifical satellites, particularly the most recent Global Positioning System (GPS), are employed. This Global Positioning System has revolutionized the navigation and positioning application because it is all-weather, world wide, and very accurate navigation and positioning system. It provides three-dimensional positions and velocities on a 24 hour a day. Therefore the combination of GPS data with the existing terrestrial data in the network computations is essential to benefit from the satellite modern measuring technology and accuracy.