Comparing the Expressiveness of Description Logics

This work studies the expressiveness of the description logics that extend ALCreg (a variant of PDL) with any combination of the features: inverse roles, nominals, quantified number restrictions, the universal role, the concept constructor for expressing the local reflexivity of a role. We compare the expressiveness of these description logics w.r.t. concepts, positive concepts, TBoxes and ABoxes. Our results about separating the expressiveness of description logics are based on bisimulations and bisimulation-based comparisons. They are naturally extended to the case when instead of ALCreg we have any sublogic of ALCreg that extends ALC.