Horn Fragments of Temporal Logics for Querying and Monitoring Log Data
- Speaker: Vladislav Ryzhikov
- Date: Wednesday, 28 November 2018 from 17:00 to 18:00
- Location: Room 151
Abstract: We consider the ontology-mediated query (OMQ) answering problem for ontologies that define events by means of temporal operators of the well-known temporal logics, such as LTL, Halpern-Shoham (based on Allen's interval algebra), and MTL (metric temporal logic). Instead of considering arbitrary formulas of those logics, that are often known to be undedicable, we restrict our attention to their Horn fragments that are expressive enough to capture relevant OMQs but have good computational properties. We present our complexity results for the ontology consistency problem as well as the data complexity results for the OMQ answering problem. Furthermore, we discuss some implementations of OMQ answering achieved by the reduction to Datalog and SQL, and their performance. Also, we consider the industrial use-cases of our approach developed in collaboration with Siemens in Munich.