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Boosting set constraint propagation for network design
 IN: CP2002, SPRINGERVERLAG
, 2002
"... This paper reconsiders the deployment of synchronous optical networks (SONET), an optimization problem naturally expressed in terms of set variables. Earlier approaches, using either MIP or CP technologies, focused on symmetry breaking, including the use of SBDS, and the design of effective branchi ..."
Abstract

Cited by 2 (2 self)
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This paper reconsiders the deployment of synchronous optical networks (SONET), an optimization problem naturally expressed in terms of set variables. Earlier approaches, using either MIP or CP technologies, focused on symmetry breaking, including the use of SBDS, and the design of effective branching strategies. This paper advocates an orthogonal approach and argues that the thrashing behavior experienced in earlier attempts is primarily due to a lack of pruning. It studies how to improve domain filtering by taking a more global view of the application and imposing redundant global constraints. The technical results include novel hardness results, propagation algorithms for global constraints, and inference rules. The paper also evaluates the contributions experimentally by presenting a novel model with static symmetricbreaking constraints and a static variable ordering which is many orders of magnitude faster than existing approaches.
Exponential Propagation for Set Variables
"... Research on constraint propagation has primarily focused on designing polynomialtime propagators sometimes at the cost of a weaker filtering. Interestingly, the evolution of constraint programming over sets have been diametrically different. The domain representations are becoming increasingly ex ..."
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Cited by 1 (0 self)
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Research on constraint propagation has primarily focused on designing polynomialtime propagators sometimes at the cost of a weaker filtering. Interestingly, the evolution of constraint programming over sets have been diametrically different. The domain representations are becoming increasingly expensive computationally and theoretical results appear to question the wisdom of these research directions. This paper explores this apparent contradiction by pursuing even more complexity in the domain representation and the filtering algorithms. It shows that the product of the lengthlex and subsetbound domains improves filtering and produces orders of magnitude improvements over existing approaches on standard benchmarks. Moreover, the paper proposes exponentialtime algorithms for NPhard intersection constraints and demonstrates that they bring significant performance improvements and speeds up constraint propagation considerably.
Boosting Network Design with Set Constraint Propagation
"... This paper reconsiders the deployment of synchronous optical networks (SONET), an optimization problem naturally expressed in terms of set variables. Earlier approaches, using either MIP or CP technologies, focused on symmetry breaking, including the use of SBDS, and the design of effective branchin ..."
Abstract
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This paper reconsiders the deployment of synchronous optical networks (SONET), an optimization problem naturally expressed in terms of set variables. Earlier approaches, using either MIP or CP technologies, focused on symmetry breaking, including the use of SBDS, and the design of effective branching strategies. This paper advocates an orthogonal approach and argues that the thrashing behavior experienced in earlier attempts is primarily due to a lack of pruning. It studies how to improve domain filtering by taking a more global view of the application and imposing redundant global constraints. The technical results include novel hardness results, propagation algorithms for global constraints, and inference rules. The paper also evaluates the contributions experimentally by presenting a novel model with static symmetricbreaking constraints and a static variable ordering which is many orders of magnitude faster than existing approaches.
Exponential Propagation for SetCSPs
"... Abstract. Research on constraint propagation has primarily focused on designing polynomialtime propagators sometimes at the cost of a weaker filtering. Interestingly, the evolution of constraint programming over sets have been diametrically different. The domain representations are becoming increas ..."
Abstract
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Abstract. Research on constraint propagation has primarily focused on designing polynomialtime propagators sometimes at the cost of a weaker filtering. Interestingly, the evolution of constraint programming over sets have been diametrically different. The domain representations are becoming increasingly expensive computationally and theoretical results appear to question the wisdom of these research directions. This paper explores this apparent contradiction by pursuing even more complexity in the domain representation and the filtering algorithms. It shows that the product of the lengthlex and subsetbound domains improves filtering and produces orders of magnitude improvements over existing approaches on standard benchmarks. Moreover, the paper proposes exponentialtime algorithms for NPhard intersection constraints and demonstrates that they bring significant performance improvements and speeds up constraint propagation considerably. 1