Results 91 to 100 of about 1,225 (183)
On Closedness of Some Homotypical Varieties of Semigroups
Journal of Mathematics, Volume 2024, Issue 1, 2024.It is well known that every subvariety of the variety of semigroups need not be absolutely closed. Thus, identifying those subvarieties that are closed in themselves or in larger varieties is an interesting open problem in the theory of semigroup dominions.
Noor Alam +6 more
wiley +1 more source
A construction for pseudocomplemented semilattices and two applications [PDF]
, 1989 A method is given by which pseudocomplemented semilattices can be constructed from graphs. Two consequences of the method are obtained, namely: there exist continuum-many quasivarieties of pseudocomplemented semilattices; for any non-zero cardinal
Matthew Gould, M. E. Adams
core +1 more source
Semilattices on Peano Continua [PDF]
Proceedings of the American Mathematical Society, 1975 A continuum is cell-cyclic if every cyclic element is an n n -cell for some integer
openaire +1 more source
Matrices generated by semilattices [PDF]
, 1995 We give a characterization of 0–1 matrices M which are generated by semilattices in the way that Mij = 0 if and only if xi Λ xj = 0̂ where xi,xj, 0̂ are elements in a ...
Karlander, Johan
core +1 more source
Journal of Applied Non-Classical LogicsContact Boolean algebras are one of the main algebraic tools in region-based theory of space. T. Ivanova provided strong motivations for the study of merely semilattices with a contact relation. Another significant motivation for considering an even weaker underlying structure comes from event structures with binary conflict in the theory of concurrent
openaire +2 more sources
Congruence lattices of semilattices [PDF]
, 1973 The main result of this paper is that the class of congruence lattices of semilattices satisfies no nontrivial lattice identities. It is also shown that the class of subalgebra lattices of semilattices satisfies no nontrivial lattice identities. As a
Nation, J. B., Freese, Ralph
core
Choice principles and lift lemmas [PDF]
Categories and General Algebraic Structures with Applications, 2017 We show that in {bf ZF} set theory without choice, the Ultrafilter mbox{Principle} ({bf UP}) is equivalent to several compactness theorems for Alexandroff discrete spaces and to Rudin's Lemma, a basic tool in topology and the theory of quasi-continuous ...
Marcel Ern'e
doaj +2 more sources
Fuzzy Ideals and Fuzzy Filters of Pseudocomplemented Semilattices
Advances in Fuzzy Systems, 2019 In this paper, we introduce the concept of kernel fuzzy ideals and ⁎-fuzzy filters of a pseudocomplemented semilattice and investigate some of their properties.
Berhanu Assaye Alaba +1 more
doaj +1 more source
c-ideals in complemented posets [PDF]
Mathematica BohemicaIn their recent paper on posets with a pseudocomplementation denoted by $*$ the first and the third author introduced the concept of a $*$-ideal. This concept is in fact an extension of a similar concept introduced in distributive pseudocomplemented ...
Ivan Chajda +2 more
doaj +1 more source
Subject-matter and intensional operators I: conditional-agnostic analytic implication. [PDF]
Philos Stud, 2023 Ferguson TM.
europepmc +1 more source