A METHOD FOR SOLVING NP SEARCH BASED ON MODEL EXPANSION AND GROUNDING

The logical task of model expansion (MX) has been proposed as a declarative constraint programming framework for solving search and decision problems. We present a method for solving NP search problems based on MX for first order logic extended with inductive definitions and cardinality constraints. The method involves grounding, and execution of a propositional solver, such as a SAT solver. Our grounding algorithm applies a generalization of the relational algebra to construct a ground formula representing the solutions to an instance. We demonstrate the practical feasibility of our method with an implementation, called MXG. We present axiomatizations of several NP-complete benchmark problems, and experimental results comparing the performance of MXG with state-of-the-art Answer Set programming (ASP) solvers. The performance of MXG is competitive with, and often better than, the ASP solvers on the problems studied.

[1]  Jean H. Gallier,et al.  Linear-Time Algorithms for Testing the Satisfiability of Propositional Horn Formulae , 1984, J. Log. Program..

[2]  David G. Mitchell,et al.  A Framework for Representing and Solving NP Search Problems , 2005, AAAI.

[3]  Moshe Y. Vardi The complexity of relational query languages (Extended Abstract) , 1982, STOC '82.

[4]  Ilkka Niemelä,et al.  Logic programs with stable model semantics as a constraint programming paradigm , 1999, Annals of Mathematics and Artificial Intelligence.

[5]  Barbara M. Smith,et al.  Reducing Symmetry in a Combinatorial Design Problem , 2001 .

[6]  Warwick Harvey Symmetry Breaking and the Social Golfer Problem , 2001 .

[7]  Gilles Audemard,et al.  Reasoning by Symmetry and Function Ordering in Finite Model Generation , 2002, CADE.

[8]  Bart Selman,et al.  Planning as Satisfiability , 1992, ECAI.

[9]  Wolfgang Faber,et al.  The DLV system for knowledge representation and reasoning , 2002, TOCL.

[10]  Pierre Flener,et al.  Introducing ESRA, a Relational Language for Modelling Combinatorial Problems , 2003, CP.

[11]  Faraz Hach,et al.  MXG : A Model Expansion Grounder and Solver , .

[12]  Larry Joseph Stockmeyer,et al.  The complexity of decision problems in automata theory and logic , 1974 .

[13]  Ilkka Niemelä,et al.  The Smodels System , 2001, LPNMR.

[14]  Francesco Scarcello,et al.  BackJumping techniques for rules instantiation in the DLV system , 2004, NMR.

[15]  Hantao Zhang,et al.  System Description: Generating Models by SEM , 1996, CADE.

[16]  Lawrence J. Henschen,et al.  Unit Refutations and Horn Sets , 1974, JACM.

[17]  Alonzo Church,et al.  A note on the Entscheidungsproblem , 1936, Journal of Symbolic Logic.

[18]  G. S. Tseitin On the Complexity of Derivation in Propositional Calculus , 1983 .

[19]  Stephen A. Cook,et al.  The complexity of theorem-proving procedures , 1971, STOC.

[20]  Kim Marriott,et al.  The Modelling Language Zinc , 2006, CP.

[21]  Neil Immerman,et al.  Descriptive Complexity , 1999, Graduate Texts in Computer Science.

[22]  Armin Biere,et al.  Symbolic Model Checking without BDDs , 1999, TACAS.

[23]  Leonid Libkin,et al.  Elements of Finite Model Theory , 2004, Texts in Theoretical Computer Science.

[24]  Eugenia Ternovska,et al.  Reducing Inductive Definitions to Propositional Satisfiability , 2005, ICLP.

[25]  Ronald Fagin Generalized first-order spectra, and polynomial. time recognizable sets , 1974 .

[26]  Yuliya Lierler,et al.  cmodels - SAT-Based Disjunctive Answer Set Solver , 2005, LPNMR.

[27]  Eugenia Ternovska,et al.  Grounding for Model Expansion in k-Guarded Formulas with Inductive Definitions , 2007, IJCAI.

[28]  Fangzhen Lin,et al.  ASSAT: computing answer sets of a logic program by SAT solvers , 2002, Artif. Intell..

[29]  W. McCune A Davis-Putnam program and its application to finite-order model search: Quasigroup existence problems , 1994 .

[30]  Warwick Harvey,et al.  Essence: A constraint language for specifying combinatorial problems , 2007, Constraints.

[31]  Miroslaw Truszczynski,et al.  The First Answer Set Programming System Competition , 2007, LPNMR.

[32]  Marc Denecker,et al.  Extending Classical Logic with Inductive Definitions , 2000, Computational Logic.

[34]  Victor W. Marek,et al.  The Logic Programming Paradigm: A 25-Year Perspective , 2011 .

[35]  DAVID MITCHELL,et al.  Model Expansion as a Framework for Modelling and Solving Search Problems , 2007 .

[36]  Martin Gebser,et al.  GrinGo : A New Grounder for Answer Set Programming , 2007, LPNMR.

[37]  K. Claessen,et al.  New Techniques that Improve MACE-style Finite Model Finding , 2007 .

[38]  Eugenia Ternovska,et al.  A Logic of Non-monotone Inductive Definitions and Its Modularity Properties , 2004, LPNMR.

[39]  Maurice Bruynooghe,et al.  Satisfiability Checking for PC(ID) , 2005, LPAR.

[40]  Martin Gebser,et al.  clasp : A Conflict-Driven Answer Set Solver , 2007, LPNMR.

[41]  Francesco Scarcello,et al.  Improving ASP Instantiators by Join-Ordering Methods , 2001, LPNMR.

[42]  Yuliya Lierler,et al.  Cmodels-2: SAT-based Answer Set Solver Enhanced to Non-tight Programs , 2004, LPNMR.

[43]  Johan Wittocx,et al.  The IDP framework for declarative problem solving , 2006 .

[44]  Hantao Zhang,et al.  ModGen: Theorem Proving by Model Generation , 1994, AAAI.