Harmony Search Algorithm with Dynamic Adjustment of PAR Values for Asymmetric Traveling Salesman Problem

This paper describes an improvement to the Harmony Search algorithm, which has been adjusted to effectively solve a problem with indisputable practical significance, i.e. Asymmetric Traveling Salesman Problem (ATSP). We modify the technique structure, enabling the value of PAR parameter to be changed dynamically, which has an impact on the frequency of greedy movements during the construction of another harmony. The article demonstrates the effectiveness of the described approach and presents a comparative study of three sets of characteristic PAR values used during the method execution. The research was conducted on a ‘test bed’ consisting of nineteen instances of the ATSP.