A Query Tool for EL with Non-monotonic Rules

Research output: Chapter in Book/Report/Conference proceedingConference contribution

16 Citations (Scopus)
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We present the Protégé plug-in NoHR that allows the user to take anEL+⊤ontology, add a set of non-monotonic (logic programming) rules – suitable e.g. to express defaults and exceptions – and query the combined knowledge base. Our approach uses the well-founded semantics for MKNF knowledge bases as underlying formalism, so no restriction other than DL-safety is imposed on the rules that can be written. The tool itself builds on the procedureSLG(O)and, with the help of OWL 2 EL reasoner ELK, pre-processes the ontology into rules, whose result together with the non-monotonic rules serve as input for the top-down querying engine XSB Prolog. With the resulting plug-in, even queries to very large ontologies, such as SNOMED CT, augmented with a large number of rules, can be processed at an interactive response time after one initial brief pre-processing period. At the same time, our system is able to deal with possible inconsistencies between the rules and an ontology that alone is consistent.
Original languageEnglish
Title of host publicationThe Semantic Web: ISWC 2013: 12th International Semantic Web Conference, Sydney, NSW, Australia, October 21-25, 2013, Proceedings, Part I
EditorsH Alani, L Kagal, A Fokoue, PT Groth, C Biemann, JX Parreira, L Aroyo, NF Noy, C Welty, K Janowicz
Place of PublicationHeidelberg
PublisherSpringer Berlin Heidelberg
ISBN (Electronic)978-3-642-41335-3
ISBN (Print)978-3-642-41334-6
Publication statusPublished - 2013
Event12th International Semantic Web Conference (ISWC 2013) - Sydney, Australia
Duration: 21 Oct 201325 Oct 2013
Conference number: 12th

Publication series

NameLecture Notes in Computer Science
PublisherSpringer Berlin Heidelberg
ISSN (Print)0302-9743


Conference12th International Semantic Web Conference (ISWC 2013)
Abbreviated titleISWC 2013


  • Description Logic
  • Conjunctive Query
  • Ground Atom
  • Atomic Concept
  • Query Tool


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