relatively countably compact subset

The text applies the covering theory to the study and discussion of the relative compact,the relative countably compact and the relative Lindelff compact.

运用覆盖理论,对相对紧、相对可数紧和相对Lindel ff紧进行研究和讨论,给出了它们之间的一些关系,并且结合相对分离性,获得某些传递等性质。

To obtain the function and imbedding properties about relative countable tightness spaces,in this paper the question whether the relative countable tightness space can be adversely preserved by a closed map is studied by means of function and imbedding theories.

为了得到相对可数紧度空间的映射及嵌入性质,借助映射方法和紧化理论讨论了相对可数紧度空间被闭映射逆保持问题及嵌入紧空间问题,得到了相对可数紧度空间被闭映射逆保持的一个充分条件、局部紧的可数紧度空间可嵌入紧空间的几个充分条件以及某一类局部紧空间在任意紧化中不具有可数紧度等结果。