فهرست نشریات علمی دسترسی آزاد ایران

Let $X$ be a Hausdorff topological space and let $\I=\fc(X)$ denote the collection of all non empty compact subsets of $X$. Let $\beta I$ denote the collection of all ultrafilters on the set $I$ and let $(\beta \I,\uplus)$ be the compact Hausdorff right topological semigroup that is the Stone-$\check{C}$ech compactification of the semigroup $(\I, \cup)$ equipped with discrete topology. A. D. Grainger and S. Koppelberg  considered $(\beta \I,\uplus)$ when $X$ is a discrete space and obtained some results about it. In this paper we study $(\beta \I,\uplus)$ when $X$ is a topological space and obtain some results from [2,3,6] .