抄録
A stochastic optimal velocity model is proposed and studied in detail. It includes the zero range process and the asymmetric simple exclusion process in special cases. The two stochastic processes are both known to be exactly solvable. The flux-density diagram shows a metastability around the intermediate density during the transition from the free state to the jamming state. It is found that the duration of the intermediate state is surprisingly long even under stochastically perturbed conditions. Moreover, the breakdown of the state into the steady jamming state happens suddenly and hence leads to a discontinuous change in the flux.