Repositioning of Empty Containers under Uncertainty by using Robust Optimization and Management Risk Combinatorial Approach (Case Study: Iranian Maritime Ports Network)

With entering container into transportation area, this area has experienced a huge change. However, the imbalance problem between the input and output containers exists in ports until now. This imbalance between import and export of goods has created a problem called Empty Container. In this paper, due to the theoretical and practical issue challenges in the problem, the reposition of empty containers under certain and uncertain conditions of some problem parameters is investigated. At first, a new model of two-objective planning of reposition of empty containers under certain conditions was presented for the first time in the literature. Thereafter, in order to reduce the effects of uncertain parameter fluctuation under various scenarios in the real world, a combinational approach of robust optimization and risk management is used. The reposition of empty containers robust model is presented by considering uncertainty of several problem parameters like demand and supply as well as loading and unloading capacity under three different scenarios which those probable scenarios are determined using risk management method. In order to evaluate and validate the both presented models, the data from Iran maritime port network are used. The computational results indicate the appropriate performance of proposed deterministic model, efficiency of proposed robust model under uncertainty conditions, and also the importance of using robust optimization approach in creating reposition of empty containers robust plans under uncertain conditions.