الفهرس 
Geographical information systemsOnly 14 pages are availabe for public view
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Abstract
The combination of GIS and Remote Sensing process problems in items of the insufficiency of available commercial 2 1/2-D GISs (3-D MAP PRODUCED/DISPLAYED ON A 2-D media).Research into GIS theory, based on point set,is isufficient without convolution with sample ellipsoids or other 3-D primitives.
Also, in the conventional models, outdated information is deleted from time to time in order to keep the system up-to date. But it is not appropriate to discard old information.In the temporal model, time value are associated with cash data items to indicate its period of validity.
3-D representation is not limited perciption. The viewing mechanism is,generally,a 2-d screen. However,the conceptual motion of representing 3-D intrinsic in the data structure, rather than as an attribute. This would define ”true 3-D”.
The most general way of storing temporally-referenced three-dimensional(3-D) data is in the form of four-Dimensional
4-D)objicts in a 4-D space-time. This allows the complete integration of space and time with all elements in the GISs domain.
the physical implimentation of spatio-temporal data is topic of study, the research on the logical view and the physical implementation of spatio-temporal data is considerd. The users are given a simple view of data and be freed of the worry of how it is physically represented. Using this approach, space and time can coexist seamlessly, providing unrestricted navigation for querying.
As most of the current GIS theories are not based on modelling and simulation, an alternative 4-D GIS ,based on the concept of physical modelling and virtual eality, is modelling, sampling, and measurements.