Finding minimum-weight spanning trees (MST) in graphs is a classic problem in operations research with important applications in network design. The basic MST problem can be solved eeciently, but the degree constrained and multiobjective versions are NP-hard. Current approaches to the degree-constrained single objective MST include Raidl's evolutionary algorithm (EA) which employs a direct tree...

In systems based on organisational specifications a reoccurring problem remains to be solved in the disparity between the level of abstractness of the organisational concepts and the concepts used in the implementation. Organisational specifications (deliberately) abstract from general practice, which creates a need to relate the abstract concepts used in the specification to concrete ones used...

The Quantified Constraint Satisfaction Problem (QCSP) is a generalization of the CSP in which some variables are universally quantified. It has been shown that a solver based on an encoding of QCSP into QBF can outperform the existing direct QCSP approaches by several orders of magnitude. In this paper we introduce an efficient QCSP solver. We show how knowledge learned from the successful enco...

Evolutionary algorithms typically use direct encodings, where each element of the phenotype is specified independently in the genotype. Because direct encodings have difficulty evolving modular and symmetric phenotypes, some researchers use indirect encodings, wherein one genomic element can influence multiple parts of a phenotype. We have previously shown that HyperNEAT, an indirect encoding, ...