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The Medvedev lattice of computably closed sets
Archive for Mathematical Logic, 2005zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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A Note on Closed Degrees of Difficulty of the Medvedev Lattice
Mathematical Logic Quarterly, 1996AbstractWe consider some nonprincipal filters of the Medvedev lattice. We prove that the filter generated by the nonzero closed degrees of difficulty is not principal and we compare this filter, with respect to inclusion, with some other filters of the lattice.
Bianchini C., Sorbi A.
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Measure of the closeness of crystal lattices
Technical Physics, 1999A numerical measure of the difference between crystal lattices is determined. The fruitfulness of the definition is demonstrated for a specific example concerning the prominence of an orientational correspondence between the body-centered crystal lattice [bcc(bct)] of α-martensite and the face-centered crystal lattice (fcc) of γ-austenite in cases ...
Vereshchagin, V. P., Kashchenko, M. P.
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Distributive Closed Inverse Subsemigroup Lattices
Semigroup Forum, 1997The closure of a subset \(H\) of an inverse semigroup \(S\) consists of all those members of \(S\) which lie above or are equal to some member of \(H\) in the natural partial order. The poset of closed inverse subsemigroups of \(S\) forms a lattice and the central result is a four-way characterization of those inverse monoids \(S\) for which this ...
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Algebraically closed and existentially closed Abelian lattice-ordered groups
Algebra universalis, 2016zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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On the spectrum of the closed-set lattice of a graph
Australas. J Comb., 1992This paper is dedicated to the study of the closed-set lattice of a graph. Main Theorem: For any finite set \(A\) of natural numbers greater than one, there exists a graph \(G\) having spectrum \(A\). It should be observed that the proofs make use of some clever ideas.
Khee Meng Koh, K. S. Poh
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Closed Patterns and Abstraction Beyond Lattices
2014Recently pattern mining has investigated closure operators in families of subsets of an attribute set that are not lattices. In particular, various authors have investigated closure operators starting from a context, in the Formal Concept Analysis (FCA) sense, in which objects are described as usual according to their relation to attributes, and in ...
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Identities in the lattices of closed classes
Discrete Mathematics and Applications, 1993Summary: The paper is devoted to the investigation of the lattice \({\mathcal L} (P_ k)\) of closed classes of functions of \(k\)-valued logic. In particular, it is proved that the lattice of subsemigroups of a free semigroup of rank \(n\) can be embedded into the lattice \({\mathcal L}(P_ k)\) for any \(k\geq 3\) if \(n=1\), and for any \(k\geq 4\) if
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Coproduct Transformations on Lattices of Closed Partial Orders
2004In the field of Knowledge Discovery, graphs of concepts are an expressive and versatile modeling technique that provides ways to reason about information implicit in the data. Typically, nodes of these graphs represent unstructured closed patterns, such as sets of items, and edges represent the relationships of specificity among them.
Gemma Casas-Garriga, José L. Balcázar
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