A Polynomial Time Subsumption Algorithm for Nominal Safe ELO_\bot under Rational Closure

In Information Sciences xxx, pages xxx-xxx, Elsevier, 2018.


Description Logics (DLs) under Rational Closure (RC) is a well-known framework for non-monotonic reasoning in DLs.
In this paper, we address the concept subsumption decision problem under RC for  nominal safe ELO_\bot, a notable and practically important DL representative of the OWL 2 profile OWL 2 EL.

Our contribution here is to define a polynomial time subsumption procedure for nominal safe ELO_\bot under RC that relies entirely on a series of classical, monotonic EL_\bot~subsumption tests. Therefore, any existing classical monotonic  EL_\bot reasoner can be used as a black box to implement our method.

We then also adapt the method to one of the known extensions of RC for DLs, namely Defeasible Inheritance-based DLs without losing the computational tractability.