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This chapter introduces and overviews an emerging methodology in search and optimisation. One of the key aims of these new approaches, which have been termed hyper-heuristics, is to raise the level of generality at which optimisation systems can operate. An objective is that hyper-heuristics will lead to more general systems that are able to handle a wide(More)
When using the Genetic Programming (GP) Algorithm on a dii-cult problem with a large set of training data, a large population size is needed and a very large number of function-tree evaluations must be carried out. This paper describes some eeorts made to reduce the number of such evaluations by concentrating on selecting a small subset of the training data(More)
It is well known that timetabling problems can be particularly difficult to solve, especially when dealing with particularly large instances. Finding near optimal results can prove to be extremely difficult, even when using advanced search methods such as evolutionary algorithms (EAs). In this paper we present a method of decomposing larger problems into(More)
In the majority of genetic algorithm implementations, the operator settings are fixed throughout a given run. However, it has been argued that these settings should vary over the course of a genetic algorithm run--so as to account for changes in the ability of the operators to produce children of increased fitness. This paper describes an investigation into(More)
We describe the General Examination/Lecture Timetabling Problem (GELTP), which covers a very broad range of real problems faced continually in educational institutions, and we describe how Evo~ lutionary Algorithms (EAs) can be employed to effectively address arbitrary instances of the GELTP. Some benchmark GELTPs are described, including real and randomly(More)
This paper presents Limited Error Fitness (LEF), a modiication to the standard supervised learning approach in Genetic Programming (GP), in which an individual's tness score is based on how many cases remain uncovered in the ordered training set after the individual exceeds an error limit. The training set order and the error limit are both altered(More)
Serum samples from 288 cetaceans representing 25 species and originating from 11 different countries were collected between 1995 and 1999 and examined for the presence of dolphin morbillivirus (DMV)-specific antibodies by an indirect ELISA (iELISA) (N = 267) or a plaque reduction assay (N = 21). A total of 35 odontocetes were seropositive: three harbour(More)
We document the abundance, composition and distribution of microplastics in sub-surface seawaters of the northeastern Pacific Ocean and coastal British Columbia. Samples were acid-digested and plastics were characterized using light microscopy by type (fibres or fragments) and size (<100, 100-500, 500-100 and >1000 μm). Microplastics concentrations ranged(More)