Zobrazeno 1 - 10
of 136
pro vyhledávání: '"Šlapal Josef"'
Autor:
Šlapal Josef
Publikováno v:
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, Vol 32, Iss 3, Pp 161-172 (2024)
We introduce a connectedness in the digital space ℤ3 induced by a quaternary relation. Using this connectedness, we prove a digital 3D Jordan-Brouwer separation theorem for boundary surfaces of the digital polyhedra that may be face-to-face tiled w
Externí odkaz:
https://doaj.org/article/d314293be1d74021bd868a39e8e88bdf
Autor:
Šlapal Josef
Publikováno v:
Open Mathematics, Vol 21, Iss 1, Pp 146-160 (2023)
After introducing a graph connectedness induced by a given set of paths of the same length, we focus on the 2-adjacency graph on the digital line Z{\mathbb{Z}} with a certain set of paths of length nn for every positive integer nn. The connectedness
Externí odkaz:
https://doaj.org/article/6cfa36cc012d4c4c811b615bdb91c27a
Autor:
Šlapal Josef
Publikováno v:
Open Mathematics, Vol 20, Iss 1, Pp 682-688 (2022)
We discuss certain closure operators that generalize the Alexandroff topologies. Such a closure operator is defined for every ordinal α>0\alpha \gt 0 in such a way that the closure of a set AA is given by closures of certain α\alpha -indexed sequen
Externí odkaz:
https://doaj.org/article/7834025308184bc69b59d19cb6c44517
Autor:
Šlapal Josef
Publikováno v:
Open Mathematics, Vol 17, Iss 1, Pp 1374-1380 (2019)
Given a simple graph with the vertex set X, we discuss a closure operator on X induced by a set of paths with identical lengths in the graph. We introduce a certain set of paths of the same length in the 2-adjacency graph on the digital line ℤ and
Externí odkaz:
https://doaj.org/article/9dc19ca15401488fbe17030f8c4b7eae
Autor:
Šlapal Josef
Publikováno v:
Open Mathematics, Vol 16, Iss 1, Pp 1573-1581 (2018)
For every positive integer n,we introduce and discuss an isotone Galois connection between the sets of paths of lengths n in a simple graph and the closure operators on the (vertex set of the) graph. We consider certain sets of paths in a particular
Externí odkaz:
https://doaj.org/article/bcbe27713876406f9dabc34b27bb6e0d
Autor:
Chaisansuk Nitima, Šlapal Josef
Publikováno v:
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, Vol 23, Iss 2, Pp 71-81 (2015)
We introduce and study a new operation of product of universal hyperalgebras which lies, with respect to set inclusion, between the cartesian product of the hyperalgebras and the cartesian product of their idempotent hulls. We give sufficient conditi
Externí odkaz:
https://doaj.org/article/467e67b4c37b4c3489513524afe06506
Departing from a suitable categorical concept of topogenous orders defined relative to the bifibration of subobjects, this note introduces and studies topogenous orders on faithful and amnestic functors. Amongst other things, it is shown that this ap
Externí odkaz:
http://arxiv.org/abs/2301.12722
Autor:
Šlapal Josef
Publikováno v:
ITM Web of Conferences, Vol 9, p 01012 (2017)
We discuss certain ternary relations, called plain, and show that each of them induces a connectedness on its underlying set. This connectedness allows for definitions of concepts of simple closed and Jordan curves. We introduce a particular plain te
Externí odkaz:
https://doaj.org/article/d47013105cbc47e9a6fa732f2f11341e
Autor:
ŠLAPAL, Josef1 slapal@fme.vutbr.cz, RICHMOND, Tom2 tom.richmond@wku.edu, IRAGI, Minani1 84miragi2016@gmail.com
Publikováno v:
Turkish Journal of Mathematics. 2024, Vol. 48 Issue 3, p469-476. 9p.