Constraint-Based Scheduling
Operations Research
Constraint Processing
Solving Project Scheduling Problems by Minimum Cut Computations
Management Science
Thesis: symmetry breaking ordering constraints
AI Communications
Resource-Constrained Project Scheduling: Models, Algorithms, Extensions and Applications
Resource-Constrained Project Scheduling: Models, Algorithms, Extensions and Applications
The Design of the Zinc Modelling Language
Constraints
Max Energy Filtering Algorithm for Discrete Cumulative Resources
CPAIOR '09 Proceedings of the 6th International Conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems
A unifying framework for structural properties of CSPs: definitions, complexity, tractabilit
Journal of Artificial Intelligence Research
Tailoring solver-independent constraint models: a case study with ESSENCE' and MINION
SARA'07 Proceedings of the 7th International conference on Abstraction, reformulation, and approximation
MiniZinc: towards a standard CP modelling language
CP'07 Proceedings of the 13th international conference on Principles and practice of constraint programming
An Integrated Solver for Optimization Problems
Operations Research
An approximative criterion for the potential of energetic reasoning
TAPAS'11 Proceedings of the First international ICST conference on Theory and practice of algorithms in (computer) systems
Explanations for the cumulative constraint: an experimental study
SEA'11 Proceedings of the 10th international conference on Experimental algorithms
CP'06 Proceedings of the 12th international conference on Principles and Practice of Constraint Programming
A constraint integer programming approach for resource-constrained project scheduling
CPAIOR'10 Proceedings of the 7th international conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems
Extending chip in order to solve complex scheduling and placement problems
Mathematical and Computer Modelling: An International Journal
A note on detecting simple redundancies in linear systems
Operations Research Letters
Counting-based search: branching heuristics for constraint satisfaction problems
Journal of Artificial Intelligence Research
A generic method for identifying and exploiting dominance relations
CP'12 Proceedings of the 18th international conference on Principles and Practice of Constraint Programming
Solving RCPSP/max by lazy clause generation
Journal of Scheduling
Hi-index | 0.00 |
Dual presolving reductions are a class of reformulation techniques that remove feasible or even optimal solutions while guaranteeing that at least one optimal solution remains, as long as the original problem was feasible. Presolving and dual reductions are important components of state-of-the-art mixed-integer linear programming solvers. In this paper, we introduce them both as unified, practical concepts in constraint programming solvers. Building on the existing idea of variable locks, we formally define and justify the use of dual information for cumulative constraints during a presolving phase of a solver. In particular, variable locks are used to decompose cumulative constraints, detect irrelevant variables, and infer variable assignments and domain reductions. Since the computational complexity of propagation algorithms typically depends on the number of variables and/or domain size, such dual reductions are a source of potential computational speed-up. Through experimental evidence on resource constrained project scheduling problems, we demonstrate that the conditions for dual reductions are present in well-known benchmark instances and that a substantial proportion of them can be solved to optimality in presolving --- without search. While we consider this result very promising, we do not observe significant change in overall run-time from the use of our novel dual reductions