Results 151 to 160 of about 106,014,988 (204)
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Categories of Relations and Functional Relations
Applied Categorical Structures, 2000Abstract: "We define relations and their composition in a category with ([Epsilon,Mu])-factorization structure, with [Mu] consisting of monomorphisms, but [Epsilon] not restricted to epimorphisms. We obtain an associativity criterion for composition of relations, and we study functional and induced relations."
Romaine Jayewardene, Oswald Wyler
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Relational Contexts and Relational Concepts
Fundamenta Informaticae, 2010Formal concept analysis (FCA) is a mathematical description and theory of concepts implied in formal contexts. And the current formal contexts of FCA aim to model the binary relations between individuals (objects) and attributes in the real world. In the real world we usually describe each individual by some attributes, which induces the relations ...
Feng Jiang, Yuefei Sui, Cungen Cao
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Relation algebra with multi-relations
International Journal of Computer Mathematics, 1998This report proposes a theory of multi-relations, which are similar to normal mathematical relations, except for the fact that each tuple has a given multiplicity. It is shown that most of the set-oriented operations on relations, such as union and intersection can be generalised (in the same way in which sets can be generalised to multisets).
Feijs, L.M.G., Krikhaar, R.L.
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The clone relation of a binary relation
Information Sciences, 2017zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Raúl Perez-Fernandez +2 more
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On Normalization of Relations in Relational Databases
Programming and Computer Software, 2002zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Relational Computation of Sets of Relations
2021We present a technique for the relational computation of sets \(\mathcal {R}\) of relations. It is based on a specification of a relation R to belong to \(\mathcal {R}\) by means of an inclusion \(\mathfrak {s}\,\subseteq \,\mathfrak {t}\), where \(\mathfrak {s}\) and \(\mathfrak {t}\) are relation-algebraic expressions constructed from a vector model ...
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Relational Databases with Ordered Relations
Logic Journal of the IGPL, 2005Summary: The paper deals with expressing preferences in the framework of the relational data model. Preferences have usually a form of a partial ordering. Therefore the question arises how to provide the relational data model with such an ordering.
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