A fuzzy interval optimization approach for p-hub median problem under uncertain information

PLoS One. 2024 Mar 15;19(3):e0297295. doi: 10.1371/journal.pone.0297295. eCollection 2024.

Abstract

Stochastic and robust optimization approaches often result in sub-optimal solutions for the uncertain p-hub median problem when continuous design parameters are discretized to form different environmental scenarios. To solve this problem, this paper proposes a triangular fuzzy number model for the Non-Strict Uncapacitated Multi-Allocation p-hub Median Problem. To enhance the quality and the speed of optimization, a novel optimization approach, combining the triangular fuzzy number evaluation index with the Genetic-Tabu Search algorithm, is proposed. During the iterations of the Genetic-Tabu Search algorithm for finding the optimal solution, the fitness of fuzzy hub schemes is calculated by considering the relative positional relationships of triangular fuzzy number membership functions. This approach directly addresses the triangular fuzzy number model and ensures the integrity of information in the p-hub problem as much as possible. It is verified by the classic Civil Aeronautics Board and several self-constructed data sets. The results indicate that, compared to the traditional Genetic Algorithm and Tabu Search algorithm, the Genetic-Tabu Search algorithm reduces average computation time by 49.05% and 40.93%, respectively. Compared to traditional random, robust, and real-number-based optimization approaches, the proposed optimization approach reduces the total cost in uncertain environments by 1.47%, 2.80%, and 8.85%, respectively.

MeSH terms

  • Algorithms*
  • Fuzzy Logic*
  • Uncertainty

Grants and funding

the National Science Foundation of China (Grant U2033213), the Open Fund of Key Laboratory of Flight Techniques and Flight Safety of the CAAC (Grant FZ2021KF12), and the Construction Plan of Scientific Research and Innovation Team for Civil Avi-ation Flight University of China (Grant JG2022-21).