Resumen

ITA, Guillermo De  y  BELLO, Pedro. Model Checking Algorithm for Repairing Inference between Conjunctive Forms. Comp. y Sist. [online]. 2022, vol.26, n.1, pp.59-70.  Epub 08-Ago-2022. ISSN 2007-9737.  https://doi.org/10.13053/cys-26-1-4152.

Let $K$ be a propositional formula and let $\varphi$ be a query, the propositional inference problem $K\models \varphi$ is a Co-NP-complete problem for propositional formulas without restrictions. We show the existence of polynomial-time cases for some fragments of propositional formulas $K$ and $\varphi$ that are different from the already known case of Horn formulas. For example, in the case that $K$ is a formula in the fragment Krom or Horn or Monotone, then $K\models \varphi$ can be decided in polynomial-time for any CNF $\varphi$.

Given two conjunctive normal forms (CNF’s) $K$ and $\varphi$, when $K⊭\varphi$, our proposal builds a minimal set of independent clauses $S$. The falsifying assignments of $S$ are exactly the subset of models of $K$, which are not models for $\varphi$. In this way, the CNF $S$ could extend the initial formula $K$ in such a way that repair the inference, it is $\left(S\cup K\right)\models \varphi$ is held.

Palabras llave : Propositional inference; repairing inference; reasoning s; NP-complete; Co-NP-complete.