Talks and Poster Presentations (with Proceedings-Entry):
T. Eiter, M. Fink, T. Krennwallner, C. Redl, P. Schüller:
"Exploiting Unfounded Sets for HEX-Program Evaluation";
Talk: 13th European Conference on Logics in Artificial Intelligence (JELIA 2012),
Toulouse, France;
2012-09-26
- 2012-09-28; in: "13th European Conference on Logics in Artificial Intelligence (JELIA 2012)",
L. del Cerro, A. Herzig, J. Mengin (ed.);
Springer,
LNCS 7519
(2012),
ISBN: 978-3-642-33352-1;
160
- 175.
English abstract:
HEX programs extend logic programs with external computations through external atoms, whose answer sets are the minimal models of the Faber-Leone-Pfeifer-reduct. As already reasoning from Horn programs with nonmonotonic external atoms of polynomial complexity is on the second level of the polynomial hierarchy, answer set checking needs special attention; simply computing reducts and searching for smaller models does not scale well. We thus extend an approach based on unfounded sets to HEX and integrate it in a Conflict Driven Clause Learning framework for HEX program evaluation. It reduces the check to a search for unfounded sets, which is more efficiently implemented as a SAT problem. We give a basic encoding for HEX and show optimizations by additional clauses. Experiments show that the new approach significantly decreases runtime.
Keywords:
Answer Set Programming, Nonmonotonic Reasoning, Unfounded Sets, FLP Semantics
"Official" electronic version of the publication (accessed through its Digital Object Identifier - DOI)
http://dx.doi.org/10.1007/978-3-642-33353-8_13
Related Projects:
Project Head Thomas Eiter:
Evaluierung von ASP Programming mit Externen Zugriffen
Project Head Thomas Eiter:
Modulare HEX-Programme
Project Head Thomas Eiter:
Schließen in hybriden Wissensbasen
Project Head Michael Fink:
Inconsistency Management for Knowledge-Integration Systems
Created from the Publication Database of the Vienna University of Technology.