Access control in multi-domain environments is one of the important questions of building coalition between domains.On the basis of RBAC access control model, t
This paper gives an overall introduction to the basic concept of LAC(location-aware computing) and its development status, puts forward an integrated location-a
In the automation of identification of landscape features the vagueness arises from the fact that the attributes and parameters that make up a landscape vary ov
The policy of the Chinese government concerning the horizontal expansion of the cultivated land through the reclamation of desert soils result in a total increa
A contour tree is a good graphical tool for representing the spatial relations of contour lines and has many applications in map generalization, map annotation,