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20212026
most citedContinuity and core compactness of topological spaces

1 citations · 1 across the 13 of their papers we have counts for

collaborators

14 papers

cs.LO2026

Finite-valuation approximable structures: a solution to the Jung--Tix problem of probabilistic powerdomains

Yuxu Chen, Hui Kou, Zhenchao Lyu

We introduce the category of finite-valuation approximable domains, a full subcategory of continuous domains contained in the category of pointed countably based FS-do…

math.CT2026

A Natural Fuzzy Order on Fuzzy Numbers

Hui Kou, Mingchun Xie

This paper introduces a natural fuzzy order on fuzzy numbers that extends the natural orders on real numbers and interval numbers. We investigate its completeness properties and sh…

math.GN2026

The reflective hull of the two-element chain in DCPO: properness, maximal Γ-faithfulness, and an internal reflection formula

Xulong He, Zhenchao Lyu, Yuxu Chen +1

Let \(\DCPO\) be the category of dcpos and Scott-continuous maps, and let \(\Rtwo\) be the reflective hull of the two-element chain \(2\). We prove that \(\Rtwo\) is the least non-…

math.GN2026

FS-domains are not always RB-domains

Yuxu Chen, Hui Kou, Zhenchao Lyu

We prove that Lawson's planar closed-disk domain is not an RB-domain. This domain is the dcpo of all closed disks in the Euclidean plane, together with the whole plane as bottom, o…

math.CO2026

Characterizing finite posets whose probabilistic powerdomain are RB-domains

Yuxu Chen, Hui Kou, Zhenchao Lyu

We classify the finite posets whose probabilistic powerdomain is an RB-domain. For a finite nonempty poset \(P\), let \(\Vone(P)\) be the probability powerdomain of , which is t…

cs.LO2023

Free dcpo-algebras via directed spaces

Yuxu Chen, Hui Kou, Zhenchao Lyu

Directed spaces are natural topological extensions of dcpos in domain theory and form a cartesian closed category. We will show that the D-completion of free algebras over a Scott…

cs.LO2022

A note on the category of c-spaces

Z. Lyu, X. Xie, H. Kou

We prove that the category of c-spaces with continuous maps is not cartesian closed. As a corollary the category of locally finitary compact spaces with continuous maps is also not…

math.CT2022

Free algebras over directed spaces

Yuxu Chen, Hui Kou

Directed spaces are natural topological extensions of dcpos in domain theory and form a cartesian closed category. In order to model nondeterministic semantics, the power structure…

math.GN2022

-convergence and locally hypercompact spaces

Yuxu Chen, Hui Kou

In this paper, we give a topological version of Scott convergence theorem for locally hypercompact spaces. We introduce the notion of -convergence on a topol…

math.GN2022

Monotone determined spaces via -generated spaces

Yuxu Chen, Hui Kou, Zhenchao Lyu

The category of monotone determined spaces is an extended topological framework for dcpos in domain theory. We first show that monotone determined spaces are exactly the spaces gen…

math.GN2022

Power structures of directed spaces

Xiaolin Xie, Yuxu Chen, Hui Kou

Powerdomains in domain theory plays an important role in modeling the semantics of nondeterministic functional programming languages.\ In this paper,\ we extend the notion of power…

math.GN2022

The Directed Probabilistic Powerspace

Xiaolin Xie, Hui Kou, Zhenchao Lyu

Probabilistic powerdomain in domain theory plays an important role in modeling the semantics of nondeterministic functional programming languages with probabilistic choice. In this…

math.GN2022★ 1 cited

Continuity and core compactness of topological spaces

Yuxu Chen, Hui Kou, Zhenchao Lyu

We investigate two approximation relations on a T0 topological space, the n-approximation, and the d-approximation, which are generalizations of the way-below relation on a dcpo. D…

math.GN2021

Two topologies on the lattice of Scott closed subsets

Yu Chen, Hui Kou, Zhenchao Lyu

For a poset , let and respectively denote the lattice of its Scott open subsets and Scott closed subsets ordered by inclusion, and set . In this paper…