Ant Colony Optimization with the Relative Pheromone Evaluation Method

In this paper the relative pheromone evaluation method for Ant Colony Optimization is investigated.We compare this method to the standard pheromone method and the summation method. Moreover we propose a new variant of the relative pheromone evaluation method. Experiments performed for various instances of the single machine scheduling problems with earliness costs and multiple due dates show the potential of the relative pheromone evaluation method.