Results 211 to 220 of about 6,919 (266)
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Modern Physics Letters B, 1987
The concept of a spiral lattice is introduced, and some mathematical properties derived. This is relevant to the prediction and characterization of states of matter intermediate between crystals, quasicrystals and glasses.
L.A. Bursill, Peng Ju Lin, Xudong Fan
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The concept of a spiral lattice is introduced, and some mathematical properties derived. This is relevant to the prediction and characterization of states of matter intermediate between crystals, quasicrystals and glasses.
L.A. Bursill, Peng Ju Lin, Xudong Fan
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Decompositions of Concept Lattices
1999A complex concept lattice can possibly be split up into simpler parts. Here the mathematical model must prove its worth by providing efficacious and versatile methods for the decomposition. Every such decomposition principle can be reversed to make a construction method.
Bernhard Ganter, Rudolf Wille
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The approximations in rough concept lattice and approximable concept lattice
Journal of Intelligent & Fuzzy Systems, 2017In a formal context, the lower and upper approximations of an arbitrary set of objects are constructed by object-oriented concepts, attribute-oriented concepts, approximable concepts and weak approximable concepts, respectively. We first define the concept of approximations based on lattice-theoretic operators, and the properties of them are discussed.
Xiao, Qimei +3 more
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CHARACTERIZING TREES IN CONCEPT LATTICES
International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems, 2008Concept lattices are systems of conceptual clusters, called formal concepts, which are partially ordered by the subconcept/superconcept relationship. Concept lattices are basic structures used in formal concept analysis. In general, a concept lattice may contain overlapping clusters and need not be a tree.
Bělohlávek, Radim +3 more
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Constraint heterogeneous concept lattices and concept lattices with heterogeneous hedges
Fuzzy Sets and Systems, 2016zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Lubomir Antoni +2 more
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Logic Journal of the IGPL, 2005
Summary: We describe a new approach to fuzzify a concept lattice and we show that it is a generalization and common platform for already known approaches: the classical crisp Ganter \& Wille [\textit{B. Ganter} and \textit{R. Wille}, Formal concept analysis. Berlin: Springer (1999; Zbl 0909.06001)] case, the fuzzy Pollandt [\textit{S. Pollandt}, in: G.
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Summary: We describe a new approach to fuzzify a concept lattice and we show that it is a generalization and common platform for already known approaches: the classical crisp Ganter \& Wille [\textit{B. Ganter} and \textit{R. Wille}, Formal concept analysis. Berlin: Springer (1999; Zbl 0909.06001)] case, the fuzzy Pollandt [\textit{S. Pollandt}, in: G.
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Constructions of concept lattices
1999A construction method by means of which we obtain from two contexts K1 and K2 a new context, let us say K, can only be a useful construction principle for concept lattices, if it is invariant under reduction. This means that, if the same construction is applied to contexts whose concept lattices are isomorphic to those of K1 and K2, then the concept ...
Bernhard Ganter, Rudolf Wille
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Properties of concept lattices
1999Mathematical lattice theory classifies lattices according to their structural properties. The most important such property, namely distributivity, has already been mentioned in Section 0.3 and has been used several times since then. Now we shall examine it a little more closely. For this purpose, we concentrate on doubly founded lattices, a choice that
Bernhard Ganter, Rudolf Wille
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Concept Approximation in Concept Lattice
2007In this paper we present a novel approach to the concept approximations in concept lattice. Using the similar idea of rough set theory and unique properties of concept lattice, upper and lower approximations of any object or attribute set can be found by exploiting meet-(union-)irreducible elements in concept lattice, the approximations can be ...
Keyun Hu1 +4 more
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Variable threshold concept lattices
Information Sciences, 2007A fuzzy formal context may be defined as a triple \((U,A,\tilde I)\) with \(U\) and \(A\) finite sets (of objects and of attributes, respectively), and \(\tilde I\colon U \times A \to L\) a binary fuzzy relation, where \(L\) is the unit interval \([0,1]\).
Zhang, Wen-Xiu +2 more
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