On Expressive Number Restrictions in Description Logics

We consider expressive Description Logics (ALCN) allowing for number restrictions on complex roles built with combinations of role constructors. In particular, we are mainly interested in Logics (called ALCN) allowing for the same kind of complex roles both in number and in value restrictions, which represent very expressive description languages and can be shown very useful for applications. We investigate the computational properties of various ALCN extensions and slightly improve the (un)decidability results following from the study publishedby Baader and Sattler in 1999. In particular, we willshow by reduction of a domino problem that ALCN(+;t) and ALCN(+;u) are undecidable.

• Type: Conference
• Year: 2001
• Where: DLOG
• Authors: Fabio Grandi
• Keywords: Automated Reasoning, Complex Roles, DLOG 2001, Expressive Description, Expressive Description Logics