A joint model of optimization and simulation methods for humanitarian logistics to face sumatra megathrust

Abstract

A rapid-appropriate relief aid is crucial to be provided in the aftermath of a disaster event. The humanitarian logistics has been considered to assist the major contribution in the disaster relief operations. This research aims to obtain an integrated strategic-operational framework for the location-allocation and routing decisions to face the future tremendous hazard Sumatra Megathrust. The arrival pattern of the two terms evacuation assignment over the 72 hours of the planning period becomes the source of the deliberation to determine the amount of consumable goods to be delivered per day. In order to ensure the safe and adequate access, this research takes into consideration the analysis of the expected impassable path caused by tsunami inundation. During the preparedness stage, Geographic Information Systems (GIS) tool with maximal coverage is applied to generate a set of Local Distribution Centers (LDCs)' alternatives to be built. The selection of the appropriate LDCs per day is assessed based on the minimum opening cost and transportation cost. Two LDCs are selected to be opened in the first two days while three LDCs will be established in the third day. The total preparedness cost for fulfilling the needs of 410,670 persons during the three days of emergency period is expected to be 7,205.86 USD. In the response stage, GIS analysis combined with simulation approach are utilized to formulate the relief routing and assignment tasks. During this stage, the demand requirements, vehicle velocities, and the road restoration time are subject of uncertainties. The use of multi-vehicle with time windows is allowed to depict the actual relief delivery efforts during three days of emergency period. The effectiveness of two relief distribution strategies, the equalized strategy and the synchronized strategy are examined by calculating the minimum total handling cost for the distribution activities, the penalty cost of the unsatisfied fulfillment, and the holding cost for the excessive delivery. The simulation result signifies that the synchronized strategy yields in better outcome with average total cost 7,716.94 USD. Meanwhile, the average total cost resulted from the equalized strategy spends 47,256.30 USD.