Communications of the
Korean Mathematical Society CKMS

Cs\'{a}sz\'{a}r [3] introduced the notions of $\gamma$-compact and $\gamma$-opera-tion on a topological space. In this paper, we introduce the notions of almost $\Gamma$-compact, $(\gamma, \tau)$-continuous function and $(\gamma, \tau)$-open function defined by $\gamma$-operation on a topological space and investigate some properties for such notions.

Keywords: $(\gamma, \tau)$-continuous, $(\gamma, \tau)$-open, $\Gamma$-closed graph, strongly $\Gamma$-closed graph, $\gamma$-compact, almost $\Gamma$-compact

MSC numbers: 54A05