节点文献
关于序列覆盖紧映射
On Sequence-Covering Compact Mappings
【摘要】 本文利用了cs网、序列邻域网、序列开网和弱基的概念,讨论了空间中点正则覆盖,一致覆盖和点有限覆盖的点星网之间的关系.建立了度量空间在几类序列覆盖(紧)映射下象空间的特征,特别地证明了度量空间的序列覆盖(或1序列覆盖)紧映象等价于具有点正则cs网的空问,回答了Tanaka等提出的一个问题.
【Abstract】 In this paper authors use the concepts of cs-networks, sequential-neighbor- hood networks, sequential-open networks and weak bases, discuss the relations among point-regular covers, uniform covers and point-star networks of point-finite covers in spaces, and establish the characterizations of images of metric spaces under some sequence-covering (compact) mappings. In particular, it is shown that the image of metric spaces under sequence-covering (or 1-sequence-covering) compact mappings is equivalent to the space with point-regular cs-networks, which answers a Tanaka’s question.
【Key words】 Point-regular cover; cs-networks; Sequential-neighborhood networks; Sequence covering mappin;
- 【文献出处】 数学学报 ,Acta Mathematica Sinica , 编辑部邮箱 ,2001年01期
- 【分类号】O189.1
- 【被引频次】27
- 【下载频次】65