There have recently been interesting new developments in the study on flow dynamics especially as regards the new macroscopic formulations of the second order. Despite the requiem which some authors wrote on these types of models the new approaches describe surprisingly well transitions of phases present in flow, from free to congested flow and vice versa. These models can be used firstly to understand better some typical traffic phenomena, such as stop-and-go, and secondly to establish new concepts for traffic control. New approaches are also stimulated by market introduction of ACC systems which can be used to apply more effective control strategies. A formula to evaluate benefits from flow control is proposed and a first application on the Padua-Mestre motorway is described by using flow parameters calculated by the above-mentioned models.
Abstract