Add to ORKGIn this paper, it is proved that a space Y is discrete if and only if every sequentially quotient mapping onto Y is bi-quotient (weak-open). Also, we discuss AP-spaces which are important generalizations of Fréchet-Urysohn spaces. We give a new characterization of AP-spaces and prove that every space is an almost-open image of some AP-space
summary:In this paper $ss$-quotient maps and $ssq$-spaces are introduced. It is shown that (1) count...
summary:The definitions of AP and WAP were originated in categorical topology by A. Pultr and A. Toz...
AbstractSay that a cardinal number κ is small relative to the space X if κ<Δ(X), where Δ(X) is the l...
Summary. A topological space X is called almost discrete if every open subset of X is closed; equiva...
Summary. A topological space X is called almost discrete if every open subset of X is closed; equiva...
We prove that the space of continuous periodic functions is a set of first category in the space of ...
summary:A dense-in-itself space $X$ is called {\it $C_\square$-discrete} if the space of real contin...
We construct a consistent example of a topological space Y= X∪ { ∞} such that: (1) Y is regular. (2)...
Summary. Let X be a topological space and let D be a subset of X. D is said to be discrete provided ...
summary:It is shown that certain weak-base structures on a topological space give a $D$-space. This ...
summary:We prove that every countably compact AP-space is Fréchet-Urysohn. It is also established th...
summary:We show that all continuous maps of a space $X$ onto second countable spaces are pseudo-open...
AbstractContinuing the study initiated by Dow, Tkachenko, Tkachuk and Wilson, we prove that countabl...
AbstractSome new classes of pseudoopen continuous mappings are introduced. Using these, we provide s...
It is shown that certain weak-base structures on a topological space give a D-space. This solves the...
summary:In this paper $ss$-quotient maps and $ssq$-spaces are introduced. It is shown that (1) count...
summary:The definitions of AP and WAP were originated in categorical topology by A. Pultr and A. Toz...
AbstractSay that a cardinal number κ is small relative to the space X if κ<Δ(X), where Δ(X) is the l...
Summary. A topological space X is called almost discrete if every open subset of X is closed; equiva...
Summary. A topological space X is called almost discrete if every open subset of X is closed; equiva...
We prove that the space of continuous periodic functions is a set of first category in the space of ...
summary:A dense-in-itself space $X$ is called {\it $C_\square$-discrete} if the space of real contin...
We construct a consistent example of a topological space Y= X∪ { ∞} such that: (1) Y is regular. (2)...
Summary. Let X be a topological space and let D be a subset of X. D is said to be discrete provided ...
summary:It is shown that certain weak-base structures on a topological space give a $D$-space. This ...
summary:We prove that every countably compact AP-space is Fréchet-Urysohn. It is also established th...
summary:We show that all continuous maps of a space $X$ onto second countable spaces are pseudo-open...
AbstractContinuing the study initiated by Dow, Tkachenko, Tkachuk and Wilson, we prove that countabl...
AbstractSome new classes of pseudoopen continuous mappings are introduced. Using these, we provide s...
It is shown that certain weak-base structures on a topological space give a D-space. This solves the...
summary:In this paper $ss$-quotient maps and $ssq$-spaces are introduced. It is shown that (1) count...
summary:The definitions of AP and WAP were originated in categorical topology by A. Pultr and A. Toz...
AbstractSay that a cardinal number κ is small relative to the space X if κ<Δ(X), where Δ(X) is the l...