A New Version Of Graph-Based Ant System For Subset Problems

A new effective graph-based ant system (GBAS) is proposed for solving subset problems. The structure graph and equivalent routes are defined for subset problems. A new updating pheromone strategy based on strengthening the pheromone on equivalent routes is presented. Ants are influenced orderly by the out-of-order information of the problem, and the information for solving the problems is increased. A route mutation mechanism is introduced, so the pheromone distribution is adjusted and the algorithm can be kept from stagnation behavior by amending the routes. After one cycle, updating the best route of this cycle, updating the best mutated route and updating no route are three instances of pheromone updating. As results the convergence speed and searching capability of the algorithm are improved. Finally, the effectiveness and superiority of the algorithm are illustrated with multidimensional knapsack problems.