On the relationship between projective distributive lattices and Boolean algebras.
On the representation of lattices by subsemigroup lattices of bands.
On the ring of the variety of algebras over a ring
On the semidirect product of the pseudovariety of semilattices by a locally finite pseudovariety of groups
On the semigroup structure of cyclic left distributive algebras.
On the semilattice of extensions of a partial algebra
On the solidity of general varieties of tree languages
For a class of hypersubstitutions 𝓚, we define the 𝓚-solidity of general varieties of tree languages (GVTLs) that contain tree languages over all alphabets, general varieties of finite algebras (GVFAs), and general varieties of finite congruences (GVFCs). We show that if 𝓚 is a so-called category of substitutions, a GVTL is 𝓚-solid exactly in case the corresponding GVFA, or the corresponding GVFC, is 𝓚-solid. We establish the solidity status of several known GVTLs with respect to certain categories...
On the Specht property of varieties of commutative alternative algebras over a field of characteristic 3 and commutative Moufang loops.
On the special context of independent sets
In this paper the context of independent sets is assigned to the complete lattice (P(M),⊆) of all subsets of a non-empty set M. Some properties of this context, especially the irreducibility and the span, are investigated.
On the structure of equationally complete varieties. I
On the structure of halfdiagonal-halfterminal-symmetric categories with diagonal inversions
The category of all binary relations between arbitrary sets turns out to be a certain symmetric monoidal category Rel with an additional structure characterized by a family of diagonal morphisms, a family of terminal morphisms, and a family of diagonal inversions having certain properties. Using this properties in [11] was given a system of axioms which characterizes the abstract concept of a halfdiagonal-halfterminal-symmetric monoidal category with diagonal inversions (hdht∇s-category)....
On the structure of quasi-ordering lattices
On the structure of semilattice sums
On the subsemilattices of first-order definable and openly first-order definable congruences of the congruence lattice of a universal algebra.
On the tensor product of a Boolean algebra and an orthoalgebra
On the tolerance extension property
On the unique factorization problem
On the varieties of Cliffordian Semigroups.
On the varieties of completely regular semigroups.
On the weak robustness of fuzzy matrices
A matrix in -algebra (fuzzy matrix) is called weakly robust if is an eigenvector of only if is an eigenvector of . The weak robustness of fuzzy matrices are studied and its properties are proved. A characterization of the weak robustness of fuzzy matrices is presented and an algorithm for checking the weak robustness is described.