Deposited in DRO : 06 July 2018 Version of attached le : Published Version Peer-review status of attached
- Environmental Science
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The complexity of constraint satisfaction games and QCSP
- Computer ScienceInf. Comput.
The Complexity of Constraint Languages
- Computer ScienceHandbook of Constraint Programming
Functions of multiple-valued logic and the complexity of constraint satisfaction: A short survey
- Computer Science33rd International Symposium on Multiple-Valued Logic, 2003. Proceedings.
This short survey discusses an approach that is related to the algebraic component of multiple-valued logic and that has proved to be very successful in studying the complexity of constraint satisfaction.
Varieties and Clones of Relational Structures
We present an axiomatization of relational varieties, i.e., classes of relational structures closed under formation of products and retracts, by a certain class of first-order sentences. We apply…
Invariance groups of functions and related Galois connections
- MathematicsBeiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry
Invariance groups of sets of Boolean functions can be characterized as Galois closures of a suitable Galois connection. We consider such groups in a much more general context using group actions of…
A polynomial-time algorithm for median-closed semilinear constraints
- Mathematics, Computer ScienceArXiv
This work proposes a polynomial-time algorithm for the CSP of semilinear constraints that are preserved by applying medians and proves that this class is maximally tractable in the sense that any larger class of semILinear relations has an NP-hard CSP.
The Complexity of Phylogeny Constraint Satisfaction Problems
- MathematicsACM Trans. Comput. Log.
The proof of the main result combines results and techniques from various research areas: a recent classification of the model-complete cores of the reducts of the homogeneous binary branching C-relation, Leeb's Ramsey theorem for rooted trees, and universal algebra.
Basics of Galois Connections
- MathematicsComplexity of Constraints
Basic properties of Galois connections between sets of relations and sets of functions or generalized functions are given and some tools for the representation of several closure operators on relations as closure operators of some Galois connection are provided.
The complexity of constraint satisfaction : an algebraic approach.
- Computer Science
An algebraic approach has proved to be very successful in studying the complexity of constraint problems and can be represented as constraint satisfaction and optimization problems.