C. Drescher, T. Eiter, M. Fink, T. Krennwallner, T. Walsh:
"Symmetry Breaking for Distributed Multi-Context Systems";
Talk: 11th International Conference on Logic Programming and Nonmonotonic Reasoning (LPNMR 2011), Vancouver, Canada; 2011-05-16 - 2011-05-19; in: "11th International Conference on Logic Programming and Nonmonotonic Reasoning", J. Delgrande, W. Faber (ed.); Springer, (2011), 26 - 39.

Heterogeneous nonmonotonic multi-context systems (MCS) permit different logics to be used in different contexts, and link them via bridge rules. We investigate the role of symmetry detection and symmetry breaking in such systems to eliminate symmetric parts of the search space and, thereby, simplify the evaluation process. We propose a distributed algorithm that takes a local stance, i.e., computes independently the partial symmetries of a context and, in order to construct potential symmetries of the whole, combines them with those partial symmetries returned by neighbouring contexts. We prove the correctness of our methods. We instantiate such symmetry detection and symmetry breaking in a multi-context system with contexts that use answer set programs, and demonstrate computational benefit on some recently proposed benchmarks.

Project Head Thomas Eiter:
Modulare HEX-Programme

Project Head Thomas Eiter:
Net2¿A Network for Enabling Networked Knowledge

Project Head Thomas Eiter:
Schließen in hybriden Wissensbasen

Project Head Michael Fink:
Inconsistency Management for Knowledge-Integration Systems