Adaptation to a changing environment by means of the feedback thermodynamical genetic algorithm

Abstract

In applications of the genetic algorithms (GA) to problems of adaptation to changing environments, maintenance of the diversity of the population is an essential requirement. Taking this point into consideration, the authors have proposed to utilize the thermodynamical genetic algorithm (TDGA) for the problems of adaptation to changing environments. The TDGA is a genetic algorithm that uses a selection rule inspired by the principle of the minimal free energy in thermodynamical systems. In the present paper, the authors propose a control method of the temperature, an adjustable parameter in the TDGA. The temperature is controlled by a feedback technique so as to regulate the level of the diversity of the population measured by entropy. The adaptation ability of the proposed method is confirmed by computer simulation taking time-varying knapsack problems as examples.