A neutrosophic subset
A of a neutrosophic topological space (U, T) is called neutrosophic semi-[alpha]-open set (briefly NS[alpha]-OS) if there exists a N[alpha]-OS K in U such that K [subset
or equal to] N [subset
or equal to] ncl(H) or equivalently if A [subset
or equal to] Ncl([alpha]Nint(A)).
1982), defined a subset
A of (X,[tau]) is called pre-open locally dense or nearly open if A [subset
] Int (Cl (A)) and its complement is called pre-closed set.
If K is a weakly compact subset
of E and K with the relative weak topology is metrizable (for example E could be a Banach space whose dual [E.
The closure (smallest closed set containing F) of a subset
or equal to] [X.
A of a space (X, [tau], I) with an ideal I is said to be pre-I-regular if it is pre-I-open and pre-I-closed.
Let A be a gJ[lambda]-closed subset
of (X, [lambda]).
The sets V [intersection] G, H [intersection] W [intersection] G and K [intersection] W [intersection] G are mutually disjoint open subsets
of G containing p, q and x, respectively.
s,t)] | [there exists]u, v with f [not subset
or equal to] [bar.
m]) be the space of all compact and convex subsets
The semi-closure  of a subset
A of X, denoted by sCl(A), is defined to be the intersection of all semi-closed sets containing A in X.
Effector T cells belonging to both subsets
were found in invasive disease.
of a topological space is called [alpha] open if A is a subset
of int cl int(A).