On the Rough Approximation of Non-Convex Set
Fang'an Deng, Tao Zhou, Yang Xu · 2007
In this article, we have established the concept of the upper and the lower approximation of nonconvex set.Meantime, the properties of rough approximation of non-convex set have been investigated.As we know, every non-convex set can be approached by the upper and lower approximation convex set with respect to a given direct.Finally, the relationship between the shadow of u and u-direction of the rough approximation sets have been given.