منابع مشابه
Categories of relational structures
The paper characterises compositional homomorphims of relational structures. A detailed study of three categories of such structures { viewed as multialgebras { reveals the one with the most desirable properties. In addition, we study analogous categories with homomorphisms mapping elements to sets (thus being relations). Finally, we indicate some consequences of our results for partial algebra...
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The relational complexity, introduced by G. Cherlin, G. Martin, and D. Saracino, is a measure of ultrahomogeneity of a relational structure. It provides an information on minimal arity of additional invariant relations needed to turn given structure into an ultrahomogeneous one. The original motivation was group theory. This work focuses more on structures and provides an alternative approach. ...
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The rippling heuristic has been rather successfully used to guide inductive proofs in a functional framework. We present here how that heuristic can be formalized in a relational framework, more adapted to logic programming. The rippling heuristic is rst analysed to identify its key components. A formalization of these to a relational framework is then presented. The applicability and the power...
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 1999
ISSN: 0011-4642,1572-9141
DOI: 10.1023/a:1022471319218