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Symmetry Breaking Constraints for Value Symmetries in Constraint Satisfaction

Y. C. Law, J. H. M. Lee
2006 Constraints  
While variable symmetry breaking constraints can be expressed easily and propagated efficiently using lexicographic ordering, value symmetry breaking constraints are often difficult to formulate.  ...  We also show when variable symmetry breaking constraints in the two CSPs, combined using channeling constraints, are consistent.  ...  Acknowledgments We thank the anonymous referees from CP'04, SAC'05, and the Constraints journal for their constructive comments which help improve the quality of the paper.  ... 
doi:10.1007/s10601-006-7095-8 fatcat:ylzxewvkmfd7dmhpip7bvwkeii

Chapter 4 Constraint Programming [chapter]

Francesca Rossi, Peter van Beek, Toby Walsh
2008 Foundations of Artificial Intelligence  
More formally, a constraint satisfaction problem consists of a set of variables, each with some domain of values, and a set of relations on subsets of these variables.  ...  In this section, we survey definitions of local consistency and constraint propagation algorithms. Backtracking algorithms integrated with constraint propagation are the topic of a subsequent section.  ...  In some cases, it is best to use multiple viewpoints and to maintain consistency between them with channeling constraints [19] .  ... 
doi:10.1016/s1574-6526(07)03004-0 fatcat:vrrxlx2nhjaajj27uvoepcefqa

Towards the Systematic Generation of Channelling Constraints [chapter]

B. Martínez-Hernández, A. M. Frisch
2005 Lecture Notes in Computer Science  
However, the combined models generated by Conjure do not include the channelling constraints needed to maintain the consistency between the alternative representations.  ...  In this paper we show that by using only the tools already provided by the Conjure system we can generate correct channelling constraints.  ...  Definition 1 R=(V, C) is a CSP instance where V is a pair consisting of a set of the variables and their domains (viewpoint) and C is a (possibly empty) set of the constraints in P.  ... 
doi:10.1007/11564751_97 fatcat:coohqsr4effcle3djf67hyr4ia

Towards 40 years of constraint reasoning

Pedro Meseguer
2012 Progress in Artificial Intelligence  
We devote special attention to constraint solving, covering popular topics such as search, inference (especially arc consistency), combination of search and inference, symmetry exploitation, global constraints  ...  This paper is a personal view of the accomplishments in this field. We summarize the main achievements along three dimensions: constraint solving, modelling and programming.  ...  Acknowledgments The author sincerely thanks Christian Bessiere, Christian Bliek, Javier Larrosa, Carme Torras and Mateu Villaret who read previous versions of this document providing many useful comments  ... 
doi:10.1007/s13748-011-0006-2 fatcat:wwikb5uf6vbfni3okf65n4y76y

Reasoning on constraints in CLP(FD)

Evelina Lamma, Michela Milano, Paola Mello
1999 The Journal of Logic Programming  
Programming examples are given, showing the advantages of the extension proposed flora both a knowledge representation and an operational viewpoint.  ...  Constraint Logic Programming solvers on finite domains (CLP(FD) solvers) use constraints to prune those combinations of assignments which cannot appear in any consistent solution.  ...  We would like to thank Pascal Van Hentenryck for useful discussions during our visit at Brown University and Carmen Gervet for providing the Conjunto code of the bin packing problem.  ... 
doi:10.1016/s0743-1066(98)10016-x fatcat:6avrf7tjsjha5gtmk4ip2jew4u

Constraints meet concurrency

Jacopo Mauro
2015 Constraints  
Thank you for your patience, your constant presence and guidance. Needless to say, I am also in debt with my coauthors:  ...  Firstly we study the expressive power of a concurrent language, namely Constraint Handling Rules, that supports constraints as a primitive construct.  ...  For this reason my first thanks goes to all the professors, assistants, colleagues and friends with whom I have had the pleasure to interact with in these years.  ... 
doi:10.1007/s10601-015-9218-6 fatcat:7cjwl2p4anfkvbpahjnklrs7my

Partial Valuation Structures for Qualitative Soft Constraints [chapter]

Alexander Schiendorfer, Alexander Knapp, Jan-Philipp Steghöfer, Gerrit Anders, Florian Siefert, Wolfgang Reif
2015 Lecture Notes in Computer Science  
Wirsing et al. have proposed partial valuation structures as a unifying algebraic structure for several soft constraint formalisms, including quantitative and qualitative ones, which, in particular, supports  ...  Soft constraints have proved to be a versatile tool for the specification and implementation of decision making in adaptive systems.  ...  We denote the set of finite multisets over a set S by M fin (S), and the multiset union by ∪ −.  ... 
doi:10.1007/978-3-319-15545-6_10 fatcat:xd2oiu5gdbejlftxr7g32hdh5u

On narrowing, refutation proofs and constraints [chapter]

Robert Nieuwenhuis
1995 Lecture Notes in Computer Science  
We develop a proof technique for dealing with narrowing and refutational theorem proving in a uniform way, clarifying the exact relationship between the existing results in both elds and allowing us to  ...  clauses, and shown compatible with simpli cation and other redundancy notions.  ...  We have proved several new results for answer computation with arbitrary Horn clauses (e.g. no restrictions on occurrences of variables) with constraints and with powerful abstract redundancy notions.  ... 
doi:10.1007/3-540-59200-8_47 fatcat:xx5kk5ztfffmxmmfbjxjrucfpm

Symmetry in Constraint Programming [chapter]

Ian P. Gent, Karen E. Petrie, Jean-François Puget
2006 Foundations of Artificial Intelligence  
A key problem in constraint programming has long been recognised: search can revisit equivalent states over and over again.  ...  Figure 10 .1: The solution to the puzzle of finding a chess position containing nine queens and a king of each colour, with the rule that no piece is on the same line (row, column or diagonal) as any queen  ...  Acknowledgments We thank all those who have helped us with this paper, most especially Barbara Smith, but also Gene Freuder, Carmen Gervet, Chris Jefferson, Steve Linton, Ian Miguel, and Toby Walsh.  ... 
doi:10.1016/s1574-6526(06)80014-3 fatcat:gcyfnj67ifelvpyjwwpruvwgq4

Removing propagation redundant constraints in redundant modeling

C. W. Choi, J. H.M. Lee, P. J. Stuckey
2007 ACM Transactions on Computational Logic  
A widely adopted approach to solving constraint satisfaction problems combines systematic tree search with various degrees of constraint propagation for pruning the search space.  ...  In this paper, we give general theorems for proving propagation redundancy of one constraint with respect to channeling constraints and constraints in the other model.  ...  More formally, a constraint c is a relation expressed using the available function and relation symbols in a specific constraint language.  ... 
doi:10.1145/1276920.1276925 fatcat:x67dzwkeybfvzchjpmpozsaimu

Removing Propagation Redundant Constraints in Redundant Modeling [article]

Chiu Wo Choi, Jimmy Ho-Man Lee, Peter J. Stuckey
2004 arXiv   pre-print
A widely adopted approach to solving constraint satisfaction problems combines systematic tree search with various degrees of constraint propagation for pruning the search space.  ...  In this paper, we give general theorems for proving propagation redundancy of one constraint with respect to channeling constraints and constraints in the other model.  ...  More formally, a constraint c is a relation expressed using available function and relation symbols in a specific constraint language.  ... 
arXiv:cs/0412026v1 fatcat:4ti4fwdxpzbgvipxnitvnt6bsy

A lazy narrowing calculus for declarative constraint programming

F. J. López-Fraguas, M. Rodríguez-Artalejo, Rafael del Vado Vírseda
2004 Proceedings of the 6th ACM SIGPLAN international conference on Principles and practice of declarative programming - PPDP '04  
This new calculus is sound and strongly complete w.r.t. the declarative semantics of CF LP (D) programs, which was formalized in [24] by means of a Constraint Rewriting Logic CRW L(D).  ...  The new generic scheme CF LP (D) has been recently proposed in [24] as a logical and semantic framework for lazy constraint functional logic programming over a parametrically given constraint domain D.  ...  In order to support a lazy semantics for the user defined functions, constraint domains D were formalized as continuous structures, with a Scott domain [13] as carrier, and a continuous interpretation  ... 
doi:10.1145/1013963.1013972 dblp:conf/ppdp/Lopez-FraguasRV04 fatcat:5m2vii25trckbk5y3wcli33roy

Default timed concurrent constraint programming

Vijay A. Saraswat, Radha Jagadeesan, Vineet Gupta
1995 Proceedings of the 22nd ACM SIGPLAN-SIGACT symposium on Principles of programming languages - POPL '95  
We provide a simple compositional semantics to the non-monotonic version of concurrent constraint programming (CCP) obtained by changing the underlying logic from intuitionistic logic to Reiter's default  ...  Default tcc thus provides a simple and natural (denotational) model capable of representing the full range of pre-emption constructs supported in ESTEREL, LUSTRE and other synchronous programming languages  ...  We gratefully acknowledge discussions with Gerard Berry, George Gonthier, Johan de Kleer, Danny Bobrow and Markus Fromherz.  ... 
doi:10.1145/199448.199513 dblp:conf/popl/SaraswatJG95 fatcat:4dmsl75wwzh27litofvutprj4i

Timed Default Concurrent Constraint Programming

VIJAY SARASWAT, RADHA JAGADEESAN, VINEET GUPTA
1996 Journal of symbolic computation  
Here we present a complete treatment of hiding, along with a detailed treatment of the model.  ...  for untimed concurrent constraint programming (CCP).  ...  We now formalize the second step of the above algorithm. De nition 3.6 Let C be a constraint system, with C its set of tokens.  ... 
doi:10.1006/jsco.1996.0064 fatcat:vkqmw4v4tnfczhop4kc76hdheu

Optimizing Compilation and Computational Complexity of Constraint Handling Rules [chapter]

Jon Sneyers
2009 Lecture Notes in Computer Science  
Constraint Handling Rules (CHR) is a very-high-level declarative programming language based on concurrent multiset rewrite rules that are conditional, multiheaded, and committed-choice.  ...  general-purpose language with a wide spectrum of application domains.  ...  As a result, for every rule R i , we know that when this rule is tried, any non-propagation rule R j with j < i, where the set of head constraints of rule R j is a (multiset) subset of that of rule R i  ... 
doi:10.1007/978-3-642-02846-5_41 fatcat:ywwhwcnysbea3alkxbrz7ppfxe
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