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An illustration of CEX crossover (see Example 2) 

An illustration of CEX crossover (see Example 2) 

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In this paper a new parallel genetic algorithm for coloring graph vertices is presented. In the algorithm we apply a migration model of parallelism and define two new recombination operators SPPX and CEX. For comparison two problem-oriented crossover operators UISX and GPX are selected. The performance of the algorithm is verified by computer exper...

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... the vertices with color conflicts by vertices taken from the other parent we obtain the following two chromosomes: s = 5, 2, 5, 2, 1, 3, 2, 5, 1, 5 and t = 1, 4, 3, 2, 3, 3, 2, 4, 2, 3 (see Figure 6). ...

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... Its relative pseudocode is as follow [12]. The HB-coloring algorithm uses the crossover greedy partition crossover(GPX), which has been proven experimentally to improve individuals by reducing the number of conflicts [13]. Two mutation operators are used, the first mutation1() is applied to the subset X r as a result of crossing. ...
... Parallel and hybrid metaheuristics are among the most promisssing methods to be developed in the nearest time [2], [20]. Many new algorithms have been already designed and compared with existing methodologies [7], [14], but there is still a room for significant progress in this area. Zbigniew In this article we focus on a class of partitioning problems that appear in many application areas like data clustering [3], column-oriented database partitioning optimization [19], design of digital circuits, decomposition of large digital systems into a number of subsystems (moduls) for multi-chip implementation, task scheduling, timetabling, assiggnment of frequencies in telecommunication networks, etc. Partitionig problems are in general simpler than permutation problems but their search spaces are too huge for exhaustive search or extensive search methods [6], [11], [13], [21], [22]. ...
... Gradually, most graph instances from this repository were assigned these distinctive numbers. The first parallel metaheuristic used for searching chromatic numbers χ(G) was Parallel Evolutionary Algorithm (PEA) [14]. Another example of graph characteristics are graph chromatic sum ∑(G) and graph chromatic sum number s(G) [16]. ...
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