Results 11 to 20 of about 1,225 (183)
Theoretical Computer Science, 1986 A subset system \({\mathcal Z}\) is an operator assigning to each poset P a collection \({\mathcal Z}(P)\) of subsets of P such that for each \(X\in {\mathcal Z}(P)\) and each order-preserving \(f: P\to Q\) we have f(X)\(\in {\mathcal Z}(Q)\). A poset P is \({\mathcal Z}\)-complete iff each \(X\in {\mathcal Z}(P)\) has a join in P.
Jirí Adámek +2 more
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Transactions of the American Mathematical Society, 1981 summary:Sectionally pseudocomplemented semilattices are an extension of relatively pseudocomplemented semilattices—they are meet-semilattices with a greatest element such that every section, i.e., every principal filter, is a pseudocomplemented ...
R. Halaš +3 more
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Discrete Mathematics, 1995 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Leonid Libkin, Vladimir Gurvich
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Canadian Mathematical Bulletin, 1980 AbstractSeveral characterizations for prime semilattices are obtained. Prime semilattices that are compactly packed by filters have been characterized. Solution to the problem, “Find a condition on a semilattice by which every filter can be expressed as the intersection of all prime filters containing it”, is furnished.
Pawar, Y. S., Thakare, N. K.
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Orthomodular semilattices [PDF]
Discrete Mathematics, 2007 Quantum structures are usually bounded posets, but attempts were made to introduce also generalizations having only the lower bound,~\(0\). Then the orthocomplement is replaced by the relative complement, \(x^a\), of \(x\) in the interval \([0,a]\).
Chajda, Ivan
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Contact Join-semilattices [PDF]
Studia Logica, 2022 Contact algebra is one of the main tools in region-based theory of space. In \cite{dmvw1, dmvw2,iv,i1} it is generalized by dropping the operation Boolean complement. Furthermore we can generalize contact algebra by dropping also the operation meet. Thus we obtain structures, called contact join-semilattices (CJS) and structures, called distributive ...
Ivanova, Tatyana
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H-Fuzzy Ideals and H-Fuzzy Filters in Distributive Join-Semilattices
Journal of MathematicsThis paper investigates H-fuzzy ideals of distributive join-semilattices with least element 0 whose codomain is a complete lattice that satisfies the infinite meet distributive law.
Mohammed Amare Mohammed +3 more
doaj +2 more sources
Bulletin of the Section of Logic, 2018 In this paper we study pseudo-BCH algebras which are semilattices or lattices with respect to the natural relations ≤; we call them pseudo-BCH join-semilattices, pseudo-BCH meet-semilattices and pseudo-BCH lattices, respectively. We prove that the class of all pseudo-BCH join-semilattices is a variety and show that it is weakly regular, arithmetical at
Walendziak, Andrzej
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Information Sciences, 1987 Properties of fuzzy ideals were considered by \textit{Y. Zhang} [BUSEFAL 27, 43-51 (1986; Zbl 0602.13002)]. Here the lattice of all fuzzy ideals of a given semilattice is considered. It has properties similar to the lattice of crisp ideals [cf. \textit{G. Grätzer}, Universal algebra (1968; Zbl 0182.342)].
Ying, M
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Reflexive Topological Semilattices [PDF]
Canadian Mathematical Bulletin, 1981 The duality between compact 0-dimensional semilattices and discrete semilattices studied by K. H. Hofmann et al. [2] is here extended to larger categories of topological semilattices.We regard topological semilattices as objects in the category CvSl of convergence semilattices, believing CvSl to be the appropriate setting for this study.
Hong, S. S., Nel, L. D.
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