Physical Sciences and Mathematics Commons^™

An Abstract View On Modularity In Knowledge Representation, Yuliya Lierler, Miroslaw Truszczyński

Yuliya Lierler

Modularity is an essential aspect of knowledge representation and reasoning theory and practice. It has received substantial attention. We introduce model-based modular systems, an abstract framework for modular knowledge representation formalisms, similar in scope to multi-context systems but employing a simpler information-flow mechanism. We establish the precise relationship between the two frameworks, showing that they can simulate each other. We demonstrate that recently introduced modular knowledge representation formalisms integrating logic programming with satisfiability and, more generally, with constraint satisfaction can be cast as modular systems in our sense. These results show that our formalism offers a simple unifying framework for …

Aspccgtk: Towards Syntactic Parsing With Semantic Disambiguation, Yuliya Lierler, Peter Schueller

Yuliya Lierler

Abstract Disjunctive Answer Set Solvers, Remi Brochenin, Yuliya Lierler, Marco Maratea

Yuliya Lierler

A fundamental task in answer set programming is to compute answer sets of logic programs. Answer set solvers are the programs that perform this task. The problem of deciding whether a disjunctive program has an answer set isΣP2 -complete. The high complexity of reasoning within disjunctive logic programming is responsible for few solvers capable of dealing with such programs, namely DLV, GNT, CMODELS and CLASP. We show that transition systems introduced by Nieuwenhuis, Oliveras, and Tinelli to model and analyze satisfiability solvers can be adapted for disjunctive answer set solvers. In particular, we present transition systems for CMODELS (without backjumping …