Mohsen Khezeli - Department of Industrial Engineering, Science and Research, Islamic Azad University (IAU),Tehran, Iran
Esmaeil Najafi - Department of Industrial Engineering, Science and Research, Islamic Azad University (IAU),Tehran, Iran
Mohammad Haji Molana - Department of Industrial Engineering, Science and Research, Islamic Azad University (IAU),Tehran, Iran
Masoud Seidi - Department of Engineering, Ilam University, Ilam, Iran

One of the most important fields of logistic network is transportation network design that has an important effect on strategic decisions in supply chain management. It has recently attracted the attention of many researchers. In this paper, a multi-stage and multi-product logistic network design is considered. This paper presents a hybrid approach based on simulation and optimization (Simulation based optimization), the model is formulated and presented in three stages.  At first, the practical production capacity of each product is calculated using the Overall Equipment Effectiveness (OEE) index, in the second stage, the optimization of loading schedules is simulated. The layout of the loading equipment, the number of equipment per line, the time of each step of the loading process, the resources used by each equipment were simulated, and the output of the model determines the maximum number of loaded vehicles in each period. Finally, a multi-objective model is presented to optimize the transportation time and cost of products. A mixed integer nonlinear programming (MINLP) model is formulated in such a way as to minimize transportation costs and maximize the use of time on the planning horizon. We have used Arena simulation software to solve the second stage of the problem, the results of which will be explained. It is also used GAMS software to solve the final stage of the model and optimize the transporting cost and find the optimal solutions. Several test problems were generated and it showed that the proposed algorithm could find good solutions in reasonable time spans.

Transportation Network Design, Supply chain management, Overall Equipment Effectiveness (OEE), mixed integer nonlinear programming, Simulation based optimization.