Port supply chain supernetwork optimization based on variational inequalities

This paper proposes a three-tier port supply chain supernetwork model, which is composed of m suppliers, n port agents and o clients. The model takes the competition within a tier and the cooperation between tiers into account, the optimality conditions for the suppliers, port agents and customs are formulated respectively using the variational inequalities. Then the optimization situation for the whole supply chain supernetwork model is illustrated. A simulated example introduced at the end of this paper turned out the validity of the model.