4617 search results - page 143 / 924 » Automation of Diagrammatic Reasoning |
209
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DLOG
2011
14 years 10 months ago
2011
We show that, although conjunctive queries over OWL 2 QL ontologies are reducible to database queries, no algorithm can construct such a reduction in polynomial time without changi...
221
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DLOG
2011
14 years 10 months ago
2011
We prove co-N2ExpTime-hardness for conjunctive query entailment in the description logic ALCOIF , thus improving the previously known 2ExpTime lower bound. The result transfers to ...
205
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DLOG
2011
14 years 10 months ago
2011
We present an optimized query rewriting algorithm for OWL 2 QL that computes the rewriting set of a user query by avoiding unnecessary inferences and extended clause subsumption ch...
219
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DLOG
2011
14 years 10 months ago
2011
We show that deciding conjunctive query inseparability for OWL 2 QL ontologies is PSpace-hard and in ExpTime. We give polynomial-time (incomplete) algorithms and demonstrate by exp...