Affiliation:
1. School of Mathematics & Physics, Anhui University of Technology, Maanshan, P.R. China
Abstract
In [6], a sufficient condition for a space to be ?-stratifiable was presented
and it was asked whether the condition is necessary. Jin et al [4] gave a
negative answer to the question by showing that a space with the condition
is zero-dimensional. In this paper, we show that a space with the condition
is precisely an almost discrete space. Moreover, we introduce the notions of
strongly lower (upper) semi-continuous functions, with which the
characterizations of ?-stratifiable spaces are presented.
Publisher
National Library of Serbia
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