Quantification of topological concepts using ideals.
Quantifying completion.
Quasi continuous selections of upper Baire continuous mappings
Quasi -compact spaces
Quasi-bounded trees and analytic inductions
A tree T on ω is said to be cofinal if for every there is some branch β of T such that α ≤ β, and quasi-bounded otherwise. We prove that the set of quasi-bounded trees is a complete Σ¹₁-inductive set. In particular, it is neither analytic nor co-analytic.
Quasicoincidence for intuitionistic fuzzy points.
Quasicone metric spaces and generalizations of Caristi Kirk's theorem.
Quasicontinuity and related properties of functions and multivalued maps
The main results presented in this paper concern multivalued maps. We consider the cliquishness, quasicontinuity, almost continuity and almost quasicontinuity; these properties of multivalued maps are characterized by the analogous properties of some real functions. The connections obtained are used to prove decomposition theorems for upper and lower quasicontinuity.
Quasi-continuous fuzzy-valued maps
Quasi-continuous multivalued mappings
Quasicontinuous selections for closed-valued multifunctions
Quasicontinuous selections for compact-valued multifunctions
Quasicontinuous spaces
We lift the notion of quasicontinuous posets to the topology context, called quasicontinuous spaces, and further study such spaces. The main results are: (1) A space is a quasicontinuous space if and only if is locally hypercompact if and only if is a hypercontinuous lattice; (2) a space is an -continuous space if and only if is a meet continuous and quasicontinuous space; (3) if a -space is a well-filtered poset under its specialization order, then is a quasicontinuous space...
Quasicontraction nonself-mappings on convex metric spaces and common fixed point theorems.
Quasi-equivalence of compacta and spaces of components.
Let X, Y be two compacta with Sh(X) = Sh (Y). Then, the spaces of components of X, Y are homeomorphic. This does not happen, in general, when X, Y are quasi-equivalent. In this paper we give a sufficient condition for the existence of a homeomorphism between the spaces of components of two quasi-equivalent compacta X, Y which maps each component in a quasi-equivalent component.
Quasi-homeomorphisms, Goldspectral spaces and Jacspectral spaces
In this paper, we deal with the study of quasi-homeomorphisms, the Goldman prime spectrum and the Jacobson prime spectrum of a commutative ring. We prove that, if is a quasi-homeomorphism, a sober space and a continuous map, then there exists a unique continuous map such that . Let be a -space, the injection of onto its sobrification . It is shown, here, that , where is the set of all locally closed points of . Some applications are also indicated. The Jacobson prime spectrum...
Quasi-homogeneous associative functions.
Quasi-metrizable spaces with a bicomplete structure.
Quasi-metrization and completion for Pervin's quasi-uniformity.
R. Stoltenberg characterized in [2] those quasi-uniformities which are quasi-pseudometrizable, as well as those quasi-metric spaces which have a quasi-metric completion. In this paper we follow Stoltenberg's work by giving characterizations for quasi-metrizability and quasi-metric completion for a particular type of quasi-uniform spaces, the Pervin's quasi-uniform space.
Quasi-metrization and hereditary normality of compact bitopological spaces