AN INTEGER PROGRAMMING-BASED HEURISTIC FOR THE MULTI-FACILITY GREEN WEBER PROBLEM

2023-8
Noman, Syed Sameer
This study considers the multi-facility green Weber problem to address the need to minimize environmental impacts of logistical activities, aligning with the growing concern for sustainability in today's world. The multi-facility green Weber problem aims to find locations of facilities such that the total amount of carbon dioxide that would be emitted from vehicles travelling between facilities and customers to satisfy customer demands is minimized. A new and effective heuristic algorithm that is based on integer programming is developed. The proposed algorithm is based on restricting candidate sites for facilities to a set of discrete locations which simplifies the problem by enabling calculation of the optimal speeds of vehicles and the amounts of carbon dioxide emissions in advance between each candidate facility location and customer . In this way, the multi-facility green Weber problem is formulated as a p-median formulation which is easily solved to optimality using an off-the-shelf solver. The proposed algorithm is composed of two phases. In the first phase, only customer locations are considered as candidate sites for locating facilities, whereas in the second phase the candidate sites for locating facilities are extended by adding a set of discrete locations close to the neighborhood of facilities located in the first phase. The computational experiments on benchmark instances of the literature indicate that the proposed algorithm achieves superior results compared to the existing studies with regard to both solution quality and time. In the small size data set, the results obtained by the proposed algorithm are competitive to those previously achieved in the literature. However, for the medium size and large size data sets, the proposed algorithm has significantly outperformed the existing heuristics with improvements ranging up to 32%. The proposed approach significantly improves solution quality and computational efficiency, making it a valuable asset for decision-makers seeking to optimize facility location strategies in various domains.
Citation Formats
S. S. Noman, “AN INTEGER PROGRAMMING-BASED HEURISTIC FOR THE MULTI-FACILITY GREEN WEBER PROBLEM,” M.S. - Master of Science, Middle East Technical University, 2023.