- From: Raphael Volz <volz@aifb.uni-karlsruhe.de>
- Date: Tue, 7 Oct 2003 14:50:21 +0200
- To: "Enrico Franconi" <franconi@inf.unibz.it>, "Raphael Volz" <rvo@aifb.uni-karlsruhe.de>
- Cc: <www-rdf-logic@w3.org>, "Boris Motik" <motik@fzi.de>
> > I would like to stay with my belief, you may choose to do some > > preprocessing and compile things and later use your polynomial language > > to do the rest. > > I don't get your point. A proof is stronger than a belief :-) I got your point, no one says that what the preprocessor does necessarily has to be tractable. > > > > > What you seems to be possible > > > > is using Disjunctive Logic Programs, but our proof that an > > > > appropriate translation is indeed correct is not quite finished > > > > yet. Empirically, we pass all tests in the OWL Test Suite and > > > > other well-known DL tests. > > > > > > Still, DLP in its full power is below PSPACE, so again no > reasonable DL Of course, the data complextity of DLP is Sgima-Pi-2, so it is still in the polynomial hierarchy, but it is Nexptime^NP-complete in the program size. We a working on a reduction of SHIQ to Disj. Datalog with equality, (w/o closed world negation !) which will for some knowledge base generate a set of rules (whose number is worst-case exponential in the size of the knowledge base), which preserves satisfiabilty and entailment. You may contact Boris (motik@fzi.de) to ask further questions and/or take his proof apart. Sincerely yours R.
Received on Tuesday, 7 October 2003 08:50:34 UTC