Expressivity of Planning with Horn Description Logic Ontologies

Talk by Stefan Borgwardt

Location: Video conference
Start: 28. April 2022 at 11:00 am
End: 28. April 2022 at 12:00 pm
Event series: Research Seminar Logic and AI
iCal

State constraints in AI Planning globally restrict the legal environment states. Standard planning languages make closed-domain and closed-world assumptions. Here we address open-world state constraints formalized by planning over a description logic (DL) ontology. Previously, this combination of DL and planning has been investigated for the light-weight DL DL-Lite. Here we propose a novel compilation scheme into standard PDDL with derived predicates, which applies to more expressive DLs and is based on the rewritability of DL queries into Datalog with stratified negation. We also provide a new rewritability result for the DL Horn-ALCHOIQ, which allows us to apply our compilation scheme to quite expressive ontologies. In contrast, we show that in the slight extension Horn-SROIQ no such compilation is possible unless the weak exponential hierarchy collapses. Finally, we show that our approach can outperform previous work on existing benchmarks for planning with DL ontologies, and is feasible on new benchmarks taking advantage of more expressive ontologies.

This talk is about joint work with Jörg Hoffmann, Alisa Kovtunova, Markus Krötzsch, Bernhard Nebel, and Marcel Steinmetz. It has been presented at the AAAI conference 2022.

Access the BBB Room for the seminar room on April 28, 11am.