A hybrid approach for the sustainable location-routing problem

Due to the disruption of ecological balances, the concept of sustainability has got involved in many parts of our lives. As a result, achieving sustainable working principles for companies has also been added in their goals. In this study, Sustainable Location-Routing Problem (SLRP) has been solved for a packaging company. To incorporate the social criterion, which is one of the components of sustainability, into the mathematical model, the Complex Proportional Assessment (COPRAS) method, utilizing fuzzy numbers, has been employed. With this method, the importance coefficients of customers have been calculated and included in the SLRP Model as a constraint. The other components of sustainability, namely environmental and economic criteria, have been included in the model with the objectives of minimizing the distance covered and minimizing costs, respectively. After defining the criteria, the mathematical model obtained has been solved using Genetic Algorithm (GA). Various parameters of GA, such as the population size, iteration number, mutation rate, and crossover rate, have been analyzed and the results obtained using different values have been examined.