几乎强次亚紧空间的一种刻画

A kind of characterization of nearly strongly submetacompact spaces

证明了如下结果:对于空间X,下列叙述是等价的:(1)空间X是几乎强次亚紧的;(2)x是几乎离散强次亚可膨胀的,都存在x的一个稠密子集D和X的任开覆盖U的开加细序列Vn n∈ω,使得对于x∈D,存在n x∈ω,使得n≥nx且α∈Σ,有x Uα∈,并且st(x,Vn)∪β≤αUβ.

The following are proved： Let X be a space, then the following are equivalent： （1） X is nearly strongly submetacompact; （2） X is nearly discretely strongly subexpandble and for every open cover 13 of X there is a dense set D and a sequence 〈∨n〉n∈ω of open refinements of 13 such that for each x ∈ D .there are nx ∈ ω such that for each n ≥ nx and α∈∑ with x∈Uα and st（x,∨n） belong to ∪β≤αUβ.