The National School Lunch Program (NSLP) provides nutritious lunch for school children. It has positive impacts on health, obesity and attendance rates. Designing a distribution network for the program requires solving a multi-echelon location routing problem. In this paper, the first two echelons involve the distribution of products from farmers to food processing centers (FPC) through distribution centers (DC). The third echelon forms a multi-depot vehicle routing problem where the locations of food processing centers and routes between schools are determined. Since the problem is NP Hard, we propose a two-stage solution approach to solve this problem. The objective is to minimize the total transportation cost in all echelons and the fixed cost of distribution and food processing centers. The first stage provides a Simulated Annealing Algorithm that handles the routing decisions of the third echelon. The second stage presents a mixed-integer linear mathematical model that determines the locations of distribution centers and solves the transportation problem in the first echelon. The performance of the proposed method is tested on several hypothetical problem instances. Computational results show that SA can be considered as an effective and efficient solution algorithm for solving the problem in terms of the computational cost and solution quality.
Anahtar Kelimeler: School Lunch Program, Multi-Echelon Location Routing Problem, Simulated Annealing Algorithm
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