Results 51 to 60 of about 101 (90)

Quasivarieties of graphs

Siberian Mathematical Journal, 1994
By a graph we mean a model of a binary predicate \(\rho(x,y)\). Many well-known properties of binary relations, such as reflexivity, symmetry, antisymmetry, transitivity, etc., are written down by means of quasiidentities. Such important classes of graphs as the class of all partial orders, the class of models of an equivalence relation, the class of ...
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Quasivariety of special jordan algebras

Algebra and Logic, 1983
It is well known that the class of all special Jordan algebras does not form a variety of algebras, but it is not difficult to see that this class forms a quasivariety of algebras. The natural question then arises whether this quasivariety can be defined by a finite number of quasi- identities.
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Model companions of the quasivarieties of polygons

Siberian Mathematical Journal, 1998
The author studies the existence problem for model companions of quasivarieties of polygons. Let \(\mathcal H\) be the class of polygons which possesses the amalgamation property and the congruence extension property. In the article under review, the existence of a model companion for \(\mathcal H\) is proven to be equivalent to each of the following ...
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The lattice of quasivarieties of undirected graphs

Algebra Universalis, 2002
For a quasivariety \(\mathcal K\), let \(L(\mathcal K)\) denote the lattice of all quasivarieties contained in \(\mathcal K \). A quasivariety \(\mathcal K\) is said to be \(Q\)-universal if for any quasivariety \(\mathcal M\) of finite type, \(L(\mathcal M )\) is a homomorphic image of a sublattice of \(L(\mathcal K)\).
Adams, M. E., Dziobiak, W.
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Quasivarieties of Algebras

2001
This chapter plays a twofold role in the book. Firstly, the chapter surveys basic facts about quasivarieties of algebras. These facts are widely utilised in the subsequent chapters devoted to algebraizable logics. Secondly, the chapter shows how the methods initially elaborated for protoalgebraic sentential logics in the first part can be also applied ...
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Dominions in quasivarieties of metabelian groups

Siberian Mathematical Journal, 2010
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Q-Universal Quasivarieties of Algebras

Proceedings of the American Mathematical Society, 1994
For any quasivariety \({\mathbf K}\) of algebras (of finite type), let \(L({\mathbf K})\) be the lattice of all quasivarieties in \({\mathbf K}\). Call \({\mathbf K}\) \(Q\)-universal iff for any quasivariety \({\mathbf M}\) (of algebras of finite type), \(L({\mathbf M})\) is a homomorphic image of a sublattice of \(L({\mathbf K})\).
Adams, M. E., Dziobiak, W.
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ON FILTERS IN THE LATTICE OF QUASIVARIETIES OF GROUPS

Mathematics of the USSR-Izvestiya, 1989
See the review in Zbl 0656.20032.
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Coverings in the lattice of quasivarieties of ℓ-groups

Siberian Mathematical Journal, 1992
See the review in Zbl 0772.06013.
Isaeva, O. V., Medvedev, N. Ya.
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Quasivarieties with Definable Relative Principal Subcongruences

Studia Logica, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Anvar M. Nurakunov, Michal M. Stronkowski   +1 more
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