本文利用点星网的概念,讨论了度量空间的π映象的性质,建立了度量空间的序列商π映象和度量空间的序列覆盖π映象的内在特征,分别推广了 Kofner J、A.和 Tanaka Y.的一些结果.

Abstract In this paper we use the concept of point-star networks, discuss some proper-ties of π-images of metric spaces, establish the characterizations of sequentially quotient π-images and sequence-coveringπ-images of metric spaces, and generalize some corresponding results of Kofner J. A. and Tanaka Y.