Evolutionary strategy ES for optimizing marker planning

In this study, the (/t + A) - evolutionary strategy (ES) was adopted. In contrast to the elitist strategy of genetic algorithms, with the aid of the + A) - ES, parents survive until they are superseded by better offspring (Back et al, 1997). The following notation is used to facilitate the presentation  

It is assumed that the current generation is t and the current population is represented by X(r), which is a population of fx individuals, and the general outline of the (/i + A) - ES is illustrated in the block diagram in Fig. 6.4. 

Select individuals from the population according to a specified selection operation. The selected individuals are then placed into a mating pool. 

Pair up the individuals in the mating pool and generate A( /r) new-born offspring individuals using the operators of recombination and mutation. In this study, each chromosome consists of three portions. For the first portion of the chromosome, discrete recombination operators, repeated exchange mutation operators, and evolutionary inversion mutation operators are employed. For the second portion of the chromosome, traditional gene-alter mutation operators and traditional discrete recombination operators are developed. For the third portion of the chromosome, exchange mutation operators and traditional discrete recombination operators are developed. 

Select /r best individuals from the combined population of parents (ju individuals) and offspring (A individuals). All the selected p, individuals are then collected to form a new population known as X(i+1), which replaces X(i) and serves as the population of individuals for the next generation/+1. 

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