When using gentic and evolutionary algorithms (GEAs) for the optimal communication spanning problem, the design of a suitable tree network encoding is crucial for finding good solutions. The link and node biased (LNB) encoding represents the structure of a tree network using a weighted vector...

This paper investigates how the use of redundant representations influences the performance ofgenetic and evolutionary algorithms. Representations are redundant if the number of genotypesexceeds the number of phenotypes. A distinction is made between synonymously and nonsynonymouslyredundant...

We consider job shop scheduling problems with release and due-dates, as well as various tardiness objectives. To date, no efficient general-purpose heuristics have been developed for these problems. genetic algorithms can be applied almost directly, but come along with apparent weaknesses.

Research infrastructures (RIs) are the most powerful means to foster cooperation on a pan-European scale and to provide efficient access to advanced methods and technologies for the scientific community.The existence, availability and easy access to leading research infrastructures is a key...

The optimal communication spanning tree (OCST) problemis a well known NP-hard combinatorial optimizationproblem which seeks a spanning tree that satisfies all givencommunication requirements for minimal total costs. Ithas been shown that optimal solutions of OCST problemsare biased towards the...

Until recently, multidimensional knapsack problems (MDKP)and winner determination problems (WDP) have been studiedindependently of each other, although WDPs can bemodelled as MDKPs. State-of-the-art optimization methodsfor WDPs are exact algorithms whereas MDKPs aremainly solved using heuristics...

The edge-set encoding is a direct encoding for trees which directly representstrees as sets of edges. In contrast to indirect representations, whereusually standard operators are applied to a list of strings and the resultingphenotype is constructed by an appropriate genotype-phenotypemapping,...

The edge-set encoding is a direct tree encoding which applies search oper-ators directly to trees represented as sets of edges. There are two variantsof crossover operators for the edge-set encoding: With heuristics that con-sider the weights of the edges, or without heuristics. Due to a strong...