A Model of an Interregional Logistic System for the Statement and Solution of Decision Problems at the Operational Level

A regional/multi-regional logistic traffic network is considered in this paper with the aim of optimizing the flows of goods which pass through the network in order to reach their final destinations. The logistic network takes into account both road and rail transportation, and it is modelled as a directed graph whose arcs represent a road or a rail link and whose nodes are not only connection points but can represent a place where some service activities (such as the change in transportation mode) are carried out. In the paper, the model of the logistic network and, in particular, the equations which formalize the dynamics of links and nodes, are described in detail. In addition, with reference to decision problems at operational level, some considerations about the degrees of freedom (decision variables) in the model, the kind and the role of decision makers, and the class of performance indicators are also outlined in the paper.