4 citations · 13 across the 28 of their papers we have counts for
9 papers · 1 filter
Tolerances on posets
Ivan Chajda, Helmut Länger
The concept of a tolerance relation, shortly called tolerance, was studied on various algebras since the seventieth of the twentieth century by B. Zelinka and the first author. Sin…
Compositions and decompositions of binary relations
Ivan Chajda, Helmut Länger
It is well-known that to every binary relation on a non-void set I there can be assigned its incidence matrix, also in the case when I is infinite. We show that a certain kind of "…
Representability of Kleene posets and Kleene lattices
Ivan Chajda, Helmut Länger, Jan Paseka
A Kleene lattice is a distributive lattice equipped with an antitone involution and satisfying the so-called normality condition. These lattices were introduced by J. A. Kalman. We…
Constructions of Kleene lattices
Ivan Chajda, Helmut Laenger, Jan Paseka
We present an easy construction producing a Kleene lattice K from an arbitrary distributive lattice L and a non-empty subset of L. We show that L can be embedded into K and compute…
Implication in finite posets with pseudocomplemented sections
Ivan Chajda, Helmut Länger
It is well-known that relatively pseudocomplemented lattices can serve as an algebraic semantics of intuitionistic logic. To extend the concept of relative pseudocomplementation to…
Conditions forcing the existence of relative complements in lattices and posets
Ivan Chajda, Helmut Länger
It is elementary and well-known that if an element x of a bounded modular lattice L has a complement in L then x has a relative complement in every interval [a,b] containing x. We…