Results 271 to 280 of about 116,063 (308)
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On integrable systems close to the toda lattice
Letters in Mathematical Physics, 1993The authors study the generalized discrete self-trapping system formulated in terms of the \(\text{u}(n)\) Lie-Poisson algebra as well as as its noncompact analog given on the \(\text{gl}(n)\) algebra. The Hamiltonian is a quadratic-linear function of the algebra generators where the quadratic part consists of the squared generators of the Cartan ...
Christiansen, Peter L. +2 more
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Which distributive lattices are lattices of closed sets?
Mathematical Proceedings of the Cambridge Philosophical Society, 19591. An elegant theorem due to Tarski states that a completely distributive complete Boolean algebra is isomorphic with a lattice of sets, and in fact the lattice of all the subsets of some aggregate. The obvious generalization of the question underlying this theorem is to ask whether one can pick out by means of a distributivity condition those lattices
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Boolean Closed Inverse Submonoid Lattices
Semigroup Forum, 1997This paper is a continuation of the author's article reviewed above (see Zbl 0887.20031). Let \(\breve H\) be the union of subgroups of an inverse monoid \(S\), let \(E\) be its semilattice of idempotents, and let \(H\) be the group of units. The main result is a characterization of those inverse monoids \(S\) whose lattice of closed inverse ...
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On the spectrum of the closed-set lattice of a graph [PDF]
Australas. J Comb., 1992 This 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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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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Semi-supervised learning on closed set lattices [PDF]
Intelligent Data Analysis, 2013 We propose a new approach for semi-supervised learning using closed set lattices, which have been recently used for frequent pattern mining within the framework of the data analysis technique of Formal Concept Analysis (FCA). We present a learning algorithm, called SELF (SEmi-supervised Learning via FCA), which performs as a multiclass classifier and a
Mahito Sugiyama, Akihiro Yamamoto
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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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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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