- From: Carsten Lutz <clu@tcs.inf.tu-dresden.de>
- Date: Thu, 08 Nov 2007 14:33:39 +0100 (CET)
- To: gstoil@image.ece.ntua.gr
- Cc: Boris Motik <boris.motik@comlab.ox.ac.uk>, public-owl-wg@w3.org
On Thu, 8 Nov 2007, gstoil@image.ece.ntua.gr wrote: > > Carsten Lutz <clu@tcs.inf.tu-dresden.de> said: > >> >> On Thu, 8 Nov 2007, gstoil@image.ece.ntua.gr wrote: >>> >>> Carsten Lutz <clu@tcs.inf.tu-dresden.de> said: >>> >>>> relation. Actually, we could think of adding the universal property >>>> and interpreting the anonymous individuals as skolem constants, as you >>>> propose. This means that, if really needed, true anonymous individuals >>>> can still be recovered via the universal property. The restriction to >>>> tree-shaped interconnections is then automatic. And we don't introduce >>>> conjunctive queries to ontology entailment. >>>> >>>> greetings, >>>> >>>> Carsten >>> >>> But is there currently any reasoning support for the universal role in SROIQ? >>> I believe there isn't any. >> >> Yes, it is in SROIQ. But even if it wasn't: it's useful, it's easily added >> to tableau algorithm, and it shouldn't be difficult to implement. >> >> greetings, >> Carsten >> > > But from the paper of SROIQ I am reading the following: That's just what I wrote: disallow it in... > Def 2: "A RIA ... not including the universal role" ...role inclusions > Def 3: "For roles R,S != U..." ...role property assertions (because the properties of the universal role are fixed) > Def 15: "...let C_o be a SROIQ-concept not using the universal role..." ...number restrictions (because you would have to do finite model reasoning if you allowed that). But *do* allow it in existential and universal restrictions. greetings, Carsten -- * Carsten Lutz, Institut f"ur Theoretische Informatik, TU Dresden * * Office phone:++49 351 46339171 mailto:lutz@tcs.inf.tu-dresden.de *
Received on Thursday, 8 November 2007 13:33:54 UTC