An optimization method for a multi-day distribution problem with shortage supplies

Abstract

Copyright © 2020 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved. We investigated a multi-day distribution problem while supplies are limited. This scenario can be found in post-natural disasters or economic crisis such as floods, earthquakes, palm oil shortage crisis, etc. The objective function of this problem is to minimize total traveling distance, unsatisfied cost, and variance of supply delivery proportion. In order to solve this multi-day problem optimally, it requires large computing memory and takes a long computational time. Therefore, we divided these large problems into multiple daily sub-problems and solved the sub-problems with the exact method. The sub-problems were solved sequentially for which the prior daily sub-problem is to be tackle first and the following daily sub-problems are defined based on the prior daily sub-problem solution. Changes were applied to update demands and to adjust delivery priority. There are three delivery priority setups proposing in this paper. Also, we present an experiment using the three proposed methods to solve modified Solomon’s vehicle routing problem datasets which extended a single period vehicle routing problem with time windows to be seven-day routing problems.