Optimization Location Routing Problem (LRP) of Humanitarian Aid Distribution Using HGASA Method in Sigi District

Disasters are events that disturb and threaten people's lives caused by nature or/and non-natural factors as well as human factors that cause casualties and economic losses. The polemic of uneven assistance and delays in the event of a natural disaster is the most common thing that occurs during a natural disaster. Location Routing Problem is a continuation of the classical routing problem that combines strategic and operational decisions with the facility location problem and the vehicle routing problem. This study aims to determine the location of the distribution centre construction and the optimal route using the Hybrid Genetic Algorithm and Simulated Annealing methods with the objective function of minimizing total costs and minimizing maximum service time for the distribution of humanitarian aid natural disaster 2018 in Sigi Regency. Optimization is designed into two scenarios, namely the construction of two distribution centres and three distribution centres. The result show that construction of two distribution centres can be designed at locations D3 and D5 with a total cost of IDR405 609 000 and a maximum travel time of 25.921 hours, while the construction of three distribution centres can be done at locations DC1, DC4 and DC 5 or with a total cost of IDR605,778,000 and a maximum service time of 19.634 hours.