Budget Amount *help 
¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥1,600,000 (Direct Cost : ¥1,600,000)

Research Abstract 
We presented a nonlinear dynamical model for traffic flow, which is called 'Optimal Velocity (OV) model', from the point of view that the traffic flow is regarded as the dynamical system of vehicles. The model successfully reproduced the dynamical formation of jam, which is usually observed in high way traffic. The spontaneous appearance of traffic jam can be treated as the phenomena of phase transition physics, and the study is one of the problems of pattern formation in complex systems such as granular flow. We made analytic study for the exact solvable OV models and revealed the mathematical properties of phase transition of OV models. We presented another OVtype model, which was expressed by the differential equation with delay, and discovered the exact solutions described with elliptic functions. The solutions indicate the relation between the pattern formation of nonequillibrium systems and soliton systems. We presented Coupled Map version based on OV model, which was applied to a simulator in order to study the behavior of real traffic flow. We performed the simulations of open boundary systems and analyzed theoretically the traffic phenomena including the effect of the fluctuations of movement of vehicles and the bottle neck. Further, we develop the simulations in realistic traffic situations, such as bottle neck (tunnel and uphill road), 2 lanes (passing and lane changing) and junction of lanes (inflow and outflow). We gather the data of high way traffic, which is the basis of the theoretical studies, and build the data base for the analysis of qualitative feature of real traffic flow. We already discovered a new physical property of microscopic behavior of 2 lanes traffic, which is a good agreement with our simulation result.
