A bi-objective single-server congested edge-based facility location problem under disruption

This study proposes a new bi-objective mixed-integer non-linear mathematical model for an interruptible single-server congested facility location problem with uniformly distributed demands along the network edges. It is assumed that in the case of server disruption, all the waiting customers leave the facility without receiving the service, and there would be no entry until fixing the server. Limiting by the maximum waiting time threshold, this study aims to determine the number and locations of established facilities. The first objective function minimizes the facility establishment costs, while the second objective function is to minimize the aggregate traveling, waiting, and demand lost costs. Due to the NP-hardness nature of the problem, several state-of-the-art evolutionary multi-objective optimization (EMO) algorithms are applied to find the set of non-dominated solutions. The results indicate that the applied SPEA-II algorithm outperforms its competitors in the majority of generated test cases.