4 citations · 13 across the 28 of their papers we have counts for
42 papers
Orthogonal adjointness in posets with
Michal Botur, Ivan Chajda, Helmut Länger
Motivated by the concept of polarity introduced by G. Birkhoff for a binary relation on a set, we introduce a concept of orthogonality in a poset with . A pair of operators ,…
Properties of the symmetric difference in lattices with complementation
Václav Cenker, Ivan Chajda, Helmut Länger
The symmetric difference in Boolean lattices can be defined in two different but equivalent forms. However, it can be introduced also in every bounded lattice with complementation…
Algebras and varieties where Sasaki operations form an adjoint pair
Ivan Chajda, Helmut Länger
The so-called Sasaki projection was introduced by U. Sasaki on the lattice L(H) of closed linear subspaces of a Hilbert space H as a projection of L(H) onto a certain sublattice of…
Tense logics based on posets
Ivan Chajda, Helmut Länger, Antonio Ledda +2
Not all logical systems can be captured using algebras. We see this in classical logic (formalized by Boolean algebras) and many-valued logics (like Lukasiewicz logic with MV-algeb…
Operators on complemented lattices
Ivan Chajda, Helmut Länger
The present paper deals with complemented lattices where, however, a unary operation of complementation is not explicitly assumed. This means that an element can have several compl…
Induced orthogonality in semilattices with 0 and in pseudocomplemented lattices and posets
Ivan Chajda, Miroslav Kolařík, Helmut Länger
On an arbitrary meet-semilattice S with 0 we define an orthogonality relation and investigate the lattice Cl(S) of all subsets of S closed under this orthogonality. We show that if…