Multimodal network design problems

In this paper we study the Multimodal Network Design Problem (MNDP); this problem arises when a decision maker (e.g, traffic authority) ean operate on different transportation modes simultaneously. For this problem we formulate a general multimodal network design model from whieh deseend multimodal and monomodal network design submodels. Possible solution approaehes and researeh perspectives are identified. This paper, therefore, provides a general framework on multimodal and monomodal network design problems and their modeling.