定義
In topological spaces, a subset A is called sg-open (semi-generalized open) if for every semiclosed set F, the semiinterior contains F whenever A contains F.
参考
R. Devi, K. Balachandran and H. Maki, Semigeneralized closed and generalized closed maps, Mem. Fac. Sci. Kochi Univ. Ser.A (Maths), 14 (1993), 41-54.