Allgemeine Kardinaloperationen
Almost ff-universal and q-universal varieties of modular 0-lattices
A variety 𝕍 of algebras of a finite type is almost ff-universal if there is a finiteness-preserving faithful functor F: 𝔾 → 𝕍 from the category 𝔾 of all graphs and their compatible maps such that Fγ is nonconstant for every γ and every nonconstant homomorphism h: FG → FG' has the form h = Fγ for some γ: G → G'. A variety 𝕍 is Q-universal if its lattice of subquasivarieties has the lattice of subquasivarieties of any quasivariety of algebras of a finite type as the quotient of its sublattice....
Almost finite-valued -groups
Almost maximal ideals
Almost orthogonality and Hausdorff interval topologies of atomic lattice effect algebras
We prove that the interval topology of an Archimedean atomic lattice effect algebra is Hausdorff whenever the set of all atoms of is almost orthogonal. In such a case is order continuous. If moreover is complete then order convergence of nets of elements of is topological and hence it coincides with convergence in the order topology and this topology is compact Hausdorff compatible with a uniformity induced by a separating function family on corresponding to compact and cocompact elements....
Almost principal element lattices.
Almost -lattices
In this paper we establish some conditions for an almost -domain to be a -domain. Next -lattices satisfying the union condition on primes are characterized. Using these results, some new characterizations are given for -rings.
Amoeba relation and Galois-Tukey connections
An algebra of quasiordered logic
An algebraic and logical approach to continuous images
An algebraic completeness proof for Kleene's 3-valued logic
We introduce Kleene's 3-valued logic in a language containing, besides the Boolean connectives, a constant for the undefined truth value, so in developing semantics we can switch from the usual treatment based on DM-algebras to the narrower class of DMF-algebras (De Morgan algebras with a single fixed point for negation). A sequent calculus for Kleene's logic is introduced and proved complete with respect to threevalent semantics. The completeness proof is based on a version of the prime ideal...
An algebraic treatment of flow diagrams and its application to generalized recursion theory
An algebraic version of the Cantor-Bernstein-Schröder theorem
The Cantor-Bernstein-Schröder theorem of the set theory was generalized by Sikorski and Tarski to -complete boolean algebras, and recently by several authors to other algebraic structures. In this paper we expose an abstract version which is applicable to algebras with an underlying lattice structure and such that the central elements of this lattice determine a direct decomposition of the algebra. Necessary and sufficient conditions for the validity of the Cantor-Bernstein-Schröder theorem for...
An algorithm to compute the möbius function of the rotation lattice of binary trees
An analogue of covering space theory for ranked posets.
An analogue of the Krein-Milman theorem for star-shaped sets.
An analysis of GCD and LCM matrices via the -factorization.
An application of soft sets to lattices
An approach to a dual of regular closure operators
An approach to covering dimensions
Using certain ideas connected with the entropy theory, several kinds of dimensions are introduced for arbitrary topological spaces. Their properties are examined, in particular, for normal spaces and quasi-discrete ones. One of the considered dimensions coincides, on these spaces, with the Čech-Lebesgue dimension and the height dimension of posets, respectively.