http://hdl.handle.net/11089/27755 2026-04-05T21:24:46Z http://hdl.handle.net/11089/28053 A post-style proof of completeness theorem for symmetric relatedness Logic S Klonowski, Mateusz One of the logic defined by Richard Epstein in a context of an analysis of subject matter relationship is Symmetric Relatedness Logic S. In the monograph [2] we can find some open problems concerning relatedness logic, a Post-style completeness theorem for logic S is one of them. Our paper introduces a solution of this metalogical issue. 2018-01-01T00:00:00Z http://hdl.handle.net/11089/28052 A comparison of two systems of point-free topology Gruszczyński, Rafał; Pietruszczak, Andrzej This is a spin-off paper to [3, 4] in which we carried out an extensive analysis of Andrzej Grzegorczyk’s point-free topology from [5]. In [1] Loredana Biacino and Giangiacomo Gerla presented an axiomatization which was inspired by the Grzegorczyk’s system, and which is its variation. Our aim is to compare the two approaches and show that they are slightly different. Except for pointing to dissimilarities, we also demonstrate that the theories coincide (in the sense that their axioms are satisfied in the same class of structures) in presence of axiom stipulating non-existence of atoms. 2018-01-01T00:00:00Z http://hdl.handle.net/11089/28051 B-almost distributive fuzzy lattice Assaye, Berhanu; Alemneh, Mihret; Tefera, Gerima The paper introduces the concept of B-Almost distributive fuzzy lattice (BADFL) in terms of its principal ideal fuzzy lattice. Necessary and sufficient conditions for an ADFL to become a B-ADFL are investigated. We also prove the equivalency of B-algebra and B-fuzzy algebra. In addition, we extend PSADL to PSADFL and prove that B-ADFL implies PSADFL. 2018-01-01T00:00:00Z http://hdl.handle.net/11089/28050 On interpolation in next (kb.alt(2)) Kostrzycka, Zofia We prove that there is infinitely many tabular modal logics extending KB.Alt(2) which have interpolation. 2018-01-01T00:00:00Z