Results 211 to 220 of about 846,298 (242)

Complete Quasi-Uniform Spaces

Canadian Mathematical Bulletin, 1980
AbstractAn example is given of a topological space that does not admit a strongly complete quasi-uniform structure.
Huffman, Shirley M., Hicks, Troy L., Carlson, John W.   +2 more
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Separation and Epimorphisms in Quasi-Uniform Spaces

Applied Categorical Structures, 2000
It is well known that the category of uniform spaces allows only for relatively few closure operators in the categorical sense. In contrast to this, the present paper shows that the category \textbf{QUnif} of quasi-uniform spaces carries plenty of different closure operators which then are studied comprehensively.
Dikran Dikranjan, Hans-Peter A. Künzi
openaire   +3 more sources

Uniqueness of Compatible Quasi-Uniformities

Canadian Mathematical Bulletin, 1972
AbstractIt is shown that a topological space has a unique compatible quasi-uniformity if its topology is finite. Examples are given to show the converse is false for T1 and for normal second countable spaces. Two sufficient conditions are given for a topological space to have a compatible quasi-uniformity strictly finer than the associated Császár ...
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Finite Quasi-Uniform Extensions. I

Acta Mathematica Hungarica, 1998
Let \(\mathcal U\) be a quasi-uniformity on a set \(X\) that generates a topology \(\tau\) on \(X\). Let \((Y,\tau')\) be a topological space for which \(X\subseteq Y\), \(\tau'| X=\tau\), and \(Y\smallsetminus X\) is finite. This paper presents a necessary and sufficient condition for the existence of a quasi-uniformity \(\mathcal U'\) on \(Y\) that ...
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Frame quasi-uniformities

Monatshefte f�r Mathematik, 1994
The authors introduce quasi-uniform locales and develop the theory as preliminary to their investigation of totally bounded quasi-uniform locales (or frames) in [Comment. Math. Univ. Carolin. 34, No. 3, 529-537 (1993; Zbl 0786.54028)].
Fletcher, P., Hunsaker, W., Lindgren, W.
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Some Results on Quasi-Uniform Spaces

Canadian Mathematical Bulletin, 1976
Constructions are made of a T1 space which does not have a T1 completion and of a quasi-uniform space which is complete, but not strongly complete. An example relating to a completion due to Popa is given. An alternate definition for Cauchy filter, called C-filter, is examined and a construction of a C-completion is given.
Carter, Karen S., Hicks, T. L.
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Nontransitive quasi-uniformities

Publicationes Mathematicae Debrecen, 1999
The question studied in the paper is to determine the number of quasi-uniformities that various kinds of topological spaces admit. Some questions posed in the basic article of \textit{A. Losonczi} [Acta Math. Hung. 79, No. 1-2, 85-116 (1998; Zbl 0906.54019)] concerning this problem are solved.
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FIBREWISE BICOMPLETE QUASI-UNIFORM SPACES

Far East Journal of Mathematical Sciences (FJMS), 2015
Summary: We introduce the notion of complete quasi-uniform spaces over a base space \(B\) and give some properties of these spaces. We introduce a general method to obtain fibrewise completion of quasi-uniform spaces over \(B\) and give internal descriptions of fibrewise completions for two different types.
Park, Jin Won, Lee, Byung Sik
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A NOTE ON THE RELATIONSHIP BETWEEN HUTTON'S QUASI-UNIFORMITIES AND SHI'S QUASI-UNIFORMITIES

2013
This note studies the relationship between Hutton's quasi-unifor- mities and Shi's quasi-uniformities. It is shown that when L satises\multiple choice principle" for co-prime elements, the category of Hutton's quasi-uniform spaces is a bireective full subcategory of the category of Shi's quasi-uniform spaces.
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Characterizations of Quasi-Uniformities†

Journal of the London Mathematical Society, 1972
Gantner, T. E., Steinlage, R. C.
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