In this paper, we introduced the concept of pseudo-commutators in BCK-algebras and then we state and prove some related theorems on these notions. Mathematics Subject Classification: Primary: 06F35 ; Secondary: 08A05, 03G25.

A minimal formula of a given logic L is a formula which is provable in L and is not a non-trivial substitution instance of other provable formulas in L. In [5], Y. Komori asked whether normal proofs of minimal formulas are unique in the implicational fragments of natural deduction systems for the intuitionistic logic and the logic BCK. It was already shown that the answer is positive for BCK, w...

Equilibrium moisture contents (EMCs) and diffusion coefficients of a high pressure laminate (HPL) overlay, a wood particleboard (PB) substrate, and an HPL backer (BCK) were measured at different levels of relative humidity (RH). The EMCs as a function of RH were fitted to the Nelson's sorption isotherm. It was found that Nelson's model reproduced accurately the experimental data of these differ...

Based on fuzzy set theory, extensions, translations and multiplications of ideals in BCK/BCI-algebras are discussed. Relations among fuzzy translations, fuzzy extensions and fuzzy multiplications of fuzzy ideals are investigated.

In this paper, we introduce the concept of doubt fuzzy H-ideals in BCKalgebras and study its some properties. Moreover, we provide characterizations of H-Artin BCK-algebras in terms of doubt fuzzy H-ideals.