Improved Ant Colony Algorithm for Solving Multi-modal Resource Constrained Project Scheduling Problem

Solving the multi-mode resource-constrained project scheduling problem is an NP-hard combinatorial optimization problem with various practical application backgrounds. Aiming at the balance between the ant colony algorithm's convergence speed and the diversity of solutions, this paper proposes an improved ant colony algorithm to solve this problem. The parameter range and change range in the algorithm can be adjusted synchronously and adaptively with the operation of the algorithm. The positive feedback process of the pheromone volatilization factor control algorithm is improved. Simultaneously, the maximum and minimum ant system algorithm and the upper and lower limits of the pheromone are introduced into the ant colony algorithm to optimize the updated strategy of pheromone.