摘要
本文引进了弱开映射,利用它把一类g-第一可数空间刻画为度量空间在不同弱开映射下的象.特别地,本文肯定回答了 Hoshina[1]的一个问题.
in this paper, we will introduce weak open mappings, by using it, certain g-first countable spaces are characterized as images of metric spaces under various weak open mappings. In purticular, this paper affirmatively answers a Hoshina's question[1].
出处
《数学进展》
CSCD
北大核心
2000年第1期61-64,共4页
Advances in Mathematics(China)
关键词
弱开映射
g-第二可数
g-第一可数
弱基
度量空间
weak open mapping, g-second countable, g-first countable, weak base, s-mapping and strong s-mapping