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Generalised arc consistency for the AllDifferent constraint: An empirical survey

Ian P. Gent, Ian Miguel, Peter Nightingale
2008 Artificial Intelligence  
This work is an analytical survey of optimizations of the main algorithm for GAC for the AllDifferent constraint. We evaluate empirically a number of key techniques from the literature.  ...  In this paper, we focus on the highest strength of inference, enforcing a property known as generalised arc consistency (GAC).  ...  We would like to thank Chris Jefferson for technical help with development in Minion [9] and helpful discussion, Andrea Rendl for use of Tailor [12] , and Max Neunhöffer for useful discussion of data  ... 
doi:10.1016/j.artint.2008.10.006 fatcat:23nirhwbqnfzlanlj6thzgsxci

Machine learning for constraint solver design -- A case study for the alldifferent constraint [article]

Ian Gent and Lars Kotthoff and Ian Miguel and Peter Nightingale
2010 arXiv   pre-print
We investigate using machine learning to make these decisions automatically depending on the problem to solve. We use the alldifferent constraint as a case study.  ...  Constraint solvers are complex pieces of software which require many design decisions to be made by the implementer based on limited information.  ...  Acknowledgements The authors thank Chris Jefferson for providing some of the feature descriptions.  ... 
arXiv:1008.4326v1 fatcat:3dkjodeuybarvhg45nn4y2r2hm

Hybrid metaheuristics for stochastic constraint programming

S. D. Prestwich, S. A. Tarim, R. Rossi, B. Hnich
2014 Constraints  
Stochastic Constraint Programming (SCP) is an extension of Constraint Programming for modelling and solving combinatorial problems involving uncertainty.  ...  This paper makes three contributions to the field. Firstly we propose a metaheuristic approach to SCP that can scale up to large problems better than state-of-the-art complete methods.  ...  hard constraints with arc consistency (AC) -a single alldifferent hard constraint with generalised arc consistency (GAC) [30] A drawback with this problem for our purposes is that FEP maps any chromosome  ... 
doi:10.1007/s10601-014-9170-x fatcat:cqv5c44wojgq5nwkzrt2g7ebu4

The power of propagation: when GAC is enough

David A. Cohen, Peter G. Jeavons
2016 Constraints  
Considerable effort in constraint programming has focused on the development of efficient propagators for individual constraints.  ...  In particular we identify classes of constraint problems where such propagators can decide the existence of a solution on their own, without the need for any additional search.  ...  When this condition holds the domains are said to satisfy the property of generalised arc-consistency (GAC) for that constraint [5] (sometimes called domain consistency or hyper-arc consistency).  ... 
doi:10.1007/s10601-016-9251-0 fatcat:yzqnbblf5vgkbhxmov2qxpvxy4

Symmetry in Constraint Programming [chapter]

Ian P. Gent, Karen E. Petrie, Jean-François Puget
2006 Foundations of Artificial Intelligence  
As we write, research remains very active for two reasons.  ...  First, there are many difficulties in the practical application of the techniques that are known for symmetry exclusion, and overcoming these remain important research problems.  ...  Parts of the writing of this paper were supported by EPSRC grants GR/R29673, EP/C523229/1 and GR/S30580/01 and Science Foundation Ireland grant 00/PI.1/C075. Bibliography  ... 
doi:10.1016/s1574-6526(06)80014-3 fatcat:gcyfnj67ifelvpyjwwpruvwgq4

Making the Most of Structure in Constraint Models

High-level modelling languages allow problems to be specified once, and then be compiled for different solving techniques to discover which to use.  ...  In particular, it proposes a framework for extracting and using structure to solve problems faster and to help users write better models and debug them.  ...  An empirical survey of some techniques for implementing the alldifferent propagator is presented in Gent et al. (2008) .  ... 
doi:10.4225/03/596daeeccfcd8 fatcat:6a5aoks3grhurhhg2i4ldfcxk4

Experimental Development of Automated Search Techniques for Discrete Combinatorial Optimisation

Bradley Michael White, University, My, Don Kerr, John Forster
In an attempt to isolate the reasons for this, a focused view of the search algorithms was adopted.  ...  A suite of techniques for finding the optimal solutions for a set of discrete combinatorial problems was developed.  ...  Although this is not invalid the arc consistency algorithms surveyed test arcs independently of one another.  ... 
doi:10.25904/1912/2070 fatcat:ragotqoa5nffnk2s7gtzibnqua

Proceedings of the 18th Irish Conference on Artificial Intelligence and Cognitive Science [chapter]

Sarah Jane Delany, Michael Madden
affordable for attendees.  ...  Their financial support has enabled the participation of our keynote speakers, the provision of a substantial prize for best paper, and a convivial social programme, while ensuring that participation remained  ...  Acknowledgment The primary author would like to acknowledge the Irish Research Council for Science, Engineering and Technology(IRCSET) for their assistance through the Embark initiative.  ... 
doi:10.21427/wmr8-km59 fatcat:wvtazmznojej3mv2uklmrtf7oi

Ship scheduling with time-varying draft restrictions: a case study in optimisation with time-varying costs [article]

Elena Kelareva, University, The Australian National, University, The Australian National
The system is now in use at Port Hedland, the world's largest bulk export port, after an investigation showed that it had the potential to increase export revenue at the port by $275 million per year.  ...  The DUKC Optimiser system won the Australia-wide NASSCOM Innovation Student Award for IT-Enabled Business Innovation in 2013.  ...  to evaluate than arc consistency for complex constraints.  ... 
doi:10.25911/5d739059090a9 fatcat:figyo56a5ndshhndb2tcmavprq

Exploiting Structures in Combinatorial Search

Md. Masbaul Alam Polash, University, My, Abdul Sattar
We then present an algorithm to perform an optimisation search that minimises the length of a Golomb ruler using the satisfaction search repeatedly.  ...  Also, during search these properties can be used as auxiliary or streamlined constraint to boost the e ciency of a search algorithm.  ...  Another CP method [22] solved up to size 14 using AllDiff constraint with bound consistency and/or arc consistency.  ... 
doi:10.25904/1912/1864 fatcat:oge7iitpdjgb3cdy3ggqx7kwxe