4 papers
The structure of multigranular rough sets
Jouni Järvinen, Sándor Radeleczki
We study multigranulation spaces of two equivalences. The lattice-theoretical properties of so-called "optimistic" and "pessimistic" multigranular approximation systems are given.…
Defining rough sets using tolerances compatible with an equivalence
Jouni Järvinen, László Kovács, Sándor Radeleczki
We consider tolerances compatible with an equivalence on , meaning that the relational product is included in . We present the essential properties of …
Prime filter structures of pseudocomplemented Kleene algebras and representation by rough sets
Jouni Järvinen, Sándor Radeleczki
We introduce Kleene-Varlet spaces as partially ordered sets equipped with a polarity satisfying certain additional conditions. By applying Kleene-Varlet spaces, we prove that each…
Intuitionistic logic with two Galois connections combined with Fischer Servi axioms
Wojciech Dzik, Jouni Järvinen, Michiro Kondo
Earlier, the authors introduced the logic IntGC, which is an extension of intuitionistic propositional logic by two rules of inference mimicking the performance of Galois connectio…