A bi-level optimization model for an ambulance routing problem for green, red, and black patients in a post-disaster stage

Document Type : Research Article

Author

Department of Mathematics and Statistics, Faculty of Basic Science and Engineering, Gonbad Kavous University, Gonbad Kavous city, golestan province, iran

Abstract

In post-disaster environments, effective allocation and routing of ambulances is crucial to minimize casualties and improve overall emergency response efficiency. This paper develops a novel bi-level programming model to address the ambulance routing problem with triage-based patient categorization, including green, red, and black patients. The upper level focuses on strategic decisions regarding ambulance allocation and dispatching, while the lower level models operational routing decisions performed by responders. The proposed approach integrates triage priorities, limited resources, and road network disruptions, yielding a realistic framework for decision support. A hybrid solution methodology based on Genetic algorithm, tabu search, and teaching learning based optimization is presented. Experimental results on test instances from existing literature demonstrate the model's capability to balance response time efficiency and prioritization of critical patients.

Keywords

Main Subjects


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