| Title: | $k$-systems, $k$-networks and $k$-covers (English) | 
| Author: | Li, Jinjin | 
| Author: | Lin, Shou | 
| Language: | English | 
| Journal: | Czechoslovak Mathematical Journal | 
| ISSN: | 0011-4642 (print) | 
| ISSN: | 1572-9141 (online) | 
| Volume: | 56 | 
| Issue: | 1 | 
| Year: | 2006 | 
| Pages: | 239-245 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | The concepts of $k$-systems, $k$-networks and $k$-covers were defined by A. Arhangel’skiǐ in  1964, P. O’Meara in  1971 and R. McCoy, I. Ntantu in  1985, respectively. In this paper the relationships among $k$-systems, $k$-networks and $k$-covers are further discussed and are established by $mk$-systems. As applications, some new characterizations of quotients or closed images of locally compact metric spaces are given by means of $mk$-systems. (English) | 
| Keyword: | $k$-systems | 
| Keyword: | $k$-networks | 
| Keyword: | $k$-covers | 
| Keyword: | $k$-spaces | 
| Keyword: | point-countable families | 
| Keyword: | hereditarily closure-preserving families | 
| MSC: | 54C10 | 
| MSC: | 54D50 | 
| MSC: | 54E45 | 
| idZBL: | Zbl 1164.54359 | 
| idMR: | MR2207015 | 
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| Date available: | 2009-09-24T11:32:34Z | 
| Last updated: | 2020-07-03 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/128062 | 
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