Characterization of all order relations in direct sums of ordered groups.
Characterization of distributive sets by generalized annihilators
Distributive ordered sets are characterized by so called generalized annihilators.
Characterization of lattices of convex subsets of posets
Characterization of posets of intervals
If is a class of partially ordered sets, let denote the system of all posets which are isomorphic to the system of all intervals of for some We give an algebraic characterization of elements of for being the class of all bounded posets and the class of all posets satisfying the condition that for each there exist a minimal element and a maximal element with respectively.
Characterizations of 0-distributive posets
The concept of a 0-distributive poset is introduced. It is shown that a section semicomplemented poset is distributive if and only if it is 0-distributive. It is also proved that every pseudocomplemented poset is 0-distributive. Further, 0-distributive posets are characterized in terms of their ideal lattices.
Characterizations of certain classes of posets having Gs-lattices of a relatively small size
Characterizations of effective sets and nonexpansive multipliers in conditionally complete and infinitely distributive partially ordered sets.
Characterizations of nonexpansive multipliers on partially ordered sets
Characterizations of the -distributive semilattice
The -distributive semilattice is characterized in terms of semiideals, ideals and filters. Some sufficient conditions and some necessary conditions for -distributivity are obtained. Counterexamples are given to prove that certain conditions are not necessary and certain conditions are not sufficient.
Characterizations of the anti-exchange closure
Characterizations of totally ordered sets by their various endomorphisms
We characterize totally ordered sets within the class of all ordered sets containing at least three-element chains using a simple relationship between their isotone transformations and the so called 2-, 3-, 4-endomorphisms which are introduced in the paper. Another characterization of totally ordered sets within the class of ordered sets of a locally finite height with at least four-element chains in terms of the regular semigroup theory is also given.
Characterizing triplets for modular pseudocomplemented ordered sets
Classification of the regular De Morgan algebras of fuzzy sets.
A characterization of regular lattices of fuzzy sets and their isomorphisms is given in Part I. A characterization of involutions on regular lattices of fuzzy sets and the isomorphisms of De Morgan algebras of fuzzy sets is given in Part II. Finally all classes of De Morgan algebras of fuzzy sets with respect to isomorphisms are completely described.
Clones closed with respect to permutation groups or transformation semigroups.
Closure operators and generating sets
Closure properties for relational systems with given endomorphism structure
Closure rings
We consider rings equipped with a closure operation defined in terms of a collection of commuting idempotents, generalising the idea of a topological closure operation defined on a ring of sets. We establish the basic properties of such rings, consider examples and construction methods, and then concentrate on rings which have a closure operation defined in terms of their lattice of central idempotents.
Coefficients d'accord entre deux préordres totaux
Coefficients d'accord entre deux préordres totaux. Comparaison ordinale des coefficients
Cofinal types of topological directed orders
We investigate the structure of the Tukey ordering among directed orders arising naturally in topology and measure theory.