الفهرس | Only 14 pages are availabe for public view |
Abstract Cities and villages in Egypt are subjected to rapid growth. Growth can be beneficial economically, but it also has significant effects on the environment, and if it is left unchecked can have negative impacts. Rapid population increase led to replace agriculture by new buildings, roads and highways. In Egypt, cities and villages are usually surrounded by agricultural areas. The changes are in particularly harmful when urban expansion occurs against surrounding agricultural areas. So the expansion of cities and villages must be monitored. Recent developments in remote sensing enable us to use high resolution satellite images for different purposes. One of the main applications for remotely sensed data is the production of large-scale topographic maps and map revisions, for which it is necessary to detect and extract features from such imagery. High resolution space images available now from IKONOS and Quick Bird do have a resolution which is partially in competition to aerial images. This thesis presents an evaluation of using IKONOS satellite images for large scale mapping purpose. This evaluation is mainly based on two elements, the first is geometric potential and the second is the information contents. The results of this study show that correcting IKONOS imagery using one or two Ground Control Points (GCPs) gives about 1.6m horizontal accuracy, higher accuracy can be obtained using more GCPs. The feature extraction is performed by manual on screen digitizing. The results are verified against a 1:25000 topographic map, features such as roads and water canals can be extracted with about 70-99% accuracy. |