Supra-Approximation Spaces Using Mixed Degree System in Graph Theory
o-space
i-space
supra-approximation space
near supra-approximation space
m-lower approximation and m-upper
approximation
This paper is concerned with introducing and studying the o-space by using out degree system (resp. i-space by using in degree system) which are the core concept in this paper. In addition, the m-lower approximations, the m-upper approximations and ospace and i-space. Furthermore, we introduce near supraopen (near supraclosed) d. g.'s. Finally, the supra-lower approximation, supraupper approximation, supra-accuracy are defined and some of its properties are investigated.
