Resumo

OSORIO, Mauricio; FIGALLO-ORELLANO, Aldo  e  HUERTA, Diego. An Alternative Definition of Stable Models Via Łukasiewicz Logic. Comp. y Sist. [online]. 2023, vol.27, n.1, pp.303-313.  Epub 16-Jun-2023. ISSN 2007-9737.  https://doi.org/10.13053/cys-27-1-4541.

Extensions of ${\text{G}}_3$ (3-valued Gödel logic) were studied as tools for knowledge representation and nonmonotonic reasoning. One of these extensions was studied and baptized as ${G^{\prime }}_3$ by Osorio et al. as a tool to define semantics of logic programming. In this work, we will explore the possibility to use another fuzzy logic for knowledge representation. In particular, we show that Łukasiewicz 3-valued logic (for short, Ł3) can be used for knowledge representation based on logic programming. Firstly, we prove that the definition of stable model for Ł3 is equivalent to the obtained through ${\text{G}}_3$ for augmented programs, but when we consider more general programs we obtain more answers for stable models on Ł3 than ${\text{G}}_3$. Finally, we present and explore a new definition of stable model based on Lukasiewicz $n$-valued logic via the use of Monteiro-Baaz $\Delta$ operator.

Palavras-chave : Knowledge representation; stable semantics; Łukasiewicz logic.