Results 271 to 280 of about 607,497 (301)

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   +2 more sources

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 ...
openaire   +3 more sources

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.
openaire   +1 more source

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.
openaire   +2 more sources

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
openaire   +2 more sources

On Optimization Problems in Quasi-uniform Spaces

Third International Conference on Natural Computation (ICNC 2007), 2007
This paper is concerned with optimization problems in T0 quasi-uniform spaces. Many optimization problems such as vector optimization, set-valued optimization, are unified in the quasi-uniform space to have a simple expression. Firstly, the proposition that a quasi-uniform space is T0 if and only if the intersection of all entourages of the quasi ...
Shao-ai Chen, Wen Li, Du Zou, Shaobai Chen   +3 more
openaire   +1 more source

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.
openaire   +2 more sources

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.
openaire   +1 more source

Characterizations of Quasi-Uniformities†

Journal of the London Mathematical Society, 1972
Gantner, T. E., Steinlage, R. C.
openaire   +2 more sources

Special Simultaneous Quasi-uniform Extensions

Acta Mathematica Hungarica, 1999
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +2 more sources