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Relational consistency by constraint filtering

Shant Karakashian, Robert J. Woodward, Berthe Y. Choueiry, Christian Bessiere
2010 Proceedings of the 2010 ACM Symposium on Applied Computing - SAC '10  
This algorithm operates by filtering the constraint while leaving the topology of the graph unchanged. We study the resulting relational consistency property and compare it to existing ones.  ...  In this paper, we propose a new algorithm for enforcing relational consistency on every set of k constraints of a finite Constraint Satisfaction Problem (CSP).  ...  Karakashian was partially supported by NSF CA-REER Award #0133568, and Woodward by a UCARE grant UNL.  ... 
doi:10.1145/1774088.1774525 dblp:conf/sac/KarakashianWCB10 fatcat:knync7uhvrgnjaesijqygcf42q

Structural Consistency: A New Filtering Approach for Constraint Networks [chapter]

Philippe Jégou, Cyril Terrioux
2014 Lecture Notes in Computer Science  
These subproblems are defined by partial constraint graphs whose tree-width is bounded by a constant w. We introduce a filtering algorithm which achieves w-SC consistency.  ...  In this paper, we introduce a new partial consistency for constraint networks which is called Structural Consistency of level w and is denoted w-SC consistency.  ...  A constraint c i ∈ C is defined by its scope, denoted S C (c i ) and by an associated relation R C (c i ).  ... 
doi:10.1007/978-3-319-04534-4_6 fatcat:hkjodyd52fbnlloxeaqs7zuq5a


Ariel Fuxman, Elham Fazli, Renée J. Miller
2005 Proceedings of the 2005 ACM SIGMOD international conference on Management of data - SIGMOD '05  
The system rewrites the queries to retrieve all (and only) data that is consistent with respect to the constraints.  ...  Although integrity constraints have long been used to maintain data consistency, there are situations in which they may not be enforced or satisfied.  ...  In this paper, we consider sets Σ of query constraints that consist of at most one key constraint per relation of the query.  ... 
doi:10.1145/1066157.1066176 dblp:conf/sigmod/FuxmanFM05 fatcat:lbugnrr6l5cw5eo3nok6wckxku

A Global Filtering Algorithm for Handling Systems of Quadratic Equations and Inequations [chapter]

Yahia Lebbah, Michel Rueher, Claude Michel
2002 Lecture Notes in Computer Science  
Such constraints are widely used to model distance relations in numerous application areas ranging from robotics to chemistry.  ...  Classical filtering algorithms are based upon local consistencies and thus, are unable to achieve a significant pruning of the domains of the variables occurring in quadratic constraints systems.  ...  Arnold Neumaier who suggested us to explore the capabilities of linearization techniques for a global handling of distance relations.  ... 
doi:10.1007/3-540-46135-3_8 fatcat:ofqwbhl2grawbgbg5df5ctnu74

Constraint-based reachability

Arnaud Gotlieb, Tristan Denmat, Nadjib Lazaar
2013 Electronic Proceedings in Theoretical Computer Science  
This paper proposes an interpretation of classical filtering consistencies used in Constraint Programming as abstract domain computations, and shows how this approach can be used to produce a constraint  ...  By combining constraint filtering and abstraction techniques, Constraint-based reachability is able to solve reachability problems which are usually outside the scope of backward or forward exploration  ...  of the results given by a filtering with domain-consistency.  ... 
doi:10.4204/eptcs.107.4 fatcat:2h3pzfzp3nginkn4dnkwp5u6ey

Implementing Propagators for Tabular Constraints [chapter]

Roman Barták, Roman Mecl
2004 Lecture Notes in Computer Science  
In the paper we study the implementation of filtering algorithms (propagators) for such tabular constraints.  ...  Many real-life constraints describing relations between the problem variables have complex semantics and the constraint domain is defined using a table of compatible tuples rather than using a formula.  ...  It is not enough to make every constraint consistent by a single call to its (complete) propagator because the domain change might influence consistency of already consistent constraints.  ... 
doi:10.1007/978-3-540-24662-6_3 fatcat:anawbqicwrhr5ogaunnhwcat44


2008 International journal on artificial intelligence tools  
Domain filtering local consistencies, such as inverse consistencies, that only delete values and do not add new constraints are particularly useful in Constraint Programming.  ...  Following this line of research, we define a number of strong domain filtering consistencies for non-binary constraints and theoretically compare their pruning power.  ...  To derive these consistencies we are mainly inspired by known relation-filtering consistencies for non-binary problems.  ... 
doi:10.1142/s0218213008004163 fatcat:mzuikwsjnnaxvc7udwt7hta35u

A New Evaluation of Forward Checking and Its Consequences on Efficiency of Tools for Decomposition of CSPs

Philippe Jégou, Samba Ndojh Ndiaye, Cyril Terrioux
2008 2008 20th IEEE International Conference on Tools with Artificial Intelligence  
Unlike what is done usually, it does not consider the size of domains, but the size of the relations associated to the constraints. It may lead sometimes to define better complexity bounds.  ...  By using this first result, we show that the tractability hierarchy proposed in [6] which compares different methods based on a decomposition of constraint networks can be seen from a new viewpoint.  ...  Acknowledgments This work is supported by an ANR grant (STAL-DEC-OPT project).  ... 
doi:10.1109/ictai.2008.116 dblp:conf/ictai/JegouNT08 fatcat:qsik2xs2jva2xem4kuq6fbdw74

A Rigorous Global Filtering Algorithm for Quadratic Constraints*

Yahia Lebbah, Claude Michel, Michel Rueher
2005 Constraints  
Such constraints are widely used to model distance relations in numerous application areas ranging from robotics to chemistry.  ...  Classical filtering algorithms are based upon local consistencies and thus, are often unable to achieve a significant pruning of the domains of the variables occurring in quadratic constraint systems.  ...  Classical filtering algorithms are based upon local consistencies such as 2Bconsistency [24] or Box-consistency [6] , and thus often achieve a very poor pruning of quadratic constraint systems.  ... 
doi:10.1007/s10601-004-5307-7 fatcat:mpn4vsly5vbqdginspfqxsdf5y

Castor: A Constraint-Based SPARQL Engine with Active Filter Processing [chapter]

Vianney le Clément de Saint-Marcq, Yves Deville, Christine Solnon, Pierre-Antoine Champin
2012 Lecture Notes in Computer Science  
State-of-the-art engines are based on relational database technologies.  ...  We approach the problem from the perspective of Constraint Programming (CP), a technology designed for solving NP-hard problems.  ...  The first author is supported as a Research Assistant by the Belgian FNRS (National Fund for Scientific Research).  ... 
doi:10.1007/978-3-642-30284-8_33 fatcat:nr5cykjrjfb3fjvoj2nwqdwy2q

Solving Constraints over Floating-Point Numbers [chapter]

C. Michel, M. Rueher, Y. Lebbah
2001 Lecture Notes in Computer Science  
We show how local-consistency filtering algorithms used in interval solvers can be adapted to achieve a safe pruning of such CSP.  ...  Relations that hold over the real numbers may not hold over the floating-point numbers. Moreover, constraints that have no solutions over the reals may hold over the floats.  ...  It generates univariate relations by replacing all existentially quantified variables but one with their intervals in the initial constraints.  ... 
doi:10.1007/3-540-45578-7_36 fatcat:pujdgh7jbnaltl57je6dhbxoem

Reformulation of Global Constraints Based on Constraints Checkers

Nicolas Beldiceanu, Mats Carlsson, Romuald Debruyne, Thierry Petit
2005 Constraints  
Under some restrictions on the signature and transition constraints, this reformulation maintains arc-consistency.  ...  This article deals with global constraints for which the set of solutions can be recognized by an extended finite automaton whose size is bounded by a polynomial in n, where n is the number of variables  ...  Then we need to extend the ternary relation by one argument corresponding to j.  ... 
doi:10.1007/s10601-005-2809-x fatcat:i7xlc5fk7rgntkfamykdggzp6m

From Constraints to Finite Automata to Filtering Algorithms [chapter]

Mats Carlsson, Nicolas Beldiceanu
2004 Lecture Notes in Computer Science  
We introduce an approach to designing filtering algorithms by derivation from finite automata operating on constraint signatures.  ...  Both algorithms maintain hyperarc consistency. Our approach can be seen as a first step towards a methodology for semi-automatic development of filtering algorithms.  ...  This latter constraint is the central building-block of lex chain. Filtering algorithms for these constraints are derived. After quoting related work, we conclude with a discussion.  ... 
doi:10.1007/978-3-540-24725-8_8 fatcat:vglbmfr6mvfbdo5yvx3mwhxzke

Beyond NP: Arc-Consistency for Quantified Constraints [chapter]

Lucas Bordeaux, Eric Monfroy
2002 Lecture Notes in Computer Science  
We propose to consider the more general problem where constraints are arbitrary relations over finite domains.  ...  Our main result is to propose quantified arc-consistency as a natural extension of the classical CSP notion. 1 As for CSPs, this name shall be used both for particular instances ("a QCP") and for the general  ...  Information provided by A. G. D. Rowley is also gratefully acknowledged. Last, we are indebted to the authors of [13] , whose title we somewhat plagiarized.  ... 
doi:10.1007/3-540-46135-3_25 fatcat:dnu3pusclzg47dto26o5e2vc5q

Accelerating filtering techniques for numeric CSPs

Yahia Lebbah, Olivier Lhomme
2002 Artificial Intelligence  
In this paper 1 we show how those filtering techniques can be accelerated by discovering and exploiting some regularities during the filtering process.  ...  Search algorithms for solving Numeric CSPs (Constraint Satisfaction Problems) make an extensive use of filtering techniques.  ...  This work has been partly supported by the Ecole des Mines de Nantes.  ... 
doi:10.1016/s0004-3702(02)00194-7 fatcat:e2yte7wxavbx5pivodz4izy74q
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