Bunching of cars in asymmetric exclusion models for freeway traffic

摘要: One-dimensional cellular automaton (CA) models are presented to simulate bunching of cars in freeway traffic. The CA three extended versions the asymmetric simple-exclusion model with parallel dynamics. In I, inherent velocities individual taken into account. It is shown that occurs since car low velocity prevents high from going ahead. mean interval 〈\ensuremath{\Delta}x〉 consecutive scales as 〈\ensuremath{\Delta}x〉\ensuremath{\approxeq}${\mathit{t}}^{0.47\ifmmode\pm\else\textpm\fi{}0.03}$ where t time. II, exclusion take account dependence transition probability T upon \ensuremath{\Delta}x particles (cars): T=\ensuremath{\Delta}${\mathit{x}}^{\mathrm{\ensuremath{-}}\mathrm{\ensuremath{\alpha}}}$ (\ensuremath{\alpha}\ensuremath{\ge}0). 〈\ensuremath{\Delta}x〉\ensuremath{\approxeq}${\mathit{t}}^{1/(1+\mathrm{\ensuremath{\alpha}})}$ by cars. III, v a depends on such manner T=1 for \ensuremath{\Delta}xg${\mathit{x}}_{\mathit{c}}$ (${\mathit{x}}_{\mathit{c}}$\ensuremath{\ge}1), and \ensuremath{\Delta}x\ensuremath{\le}${\mathit{x}}_{\mathit{c}}$, T=(\ensuremath{\Delta}x/${\mathit{x}}_{\mathit{c}}$${)}^{\mathrm{\ensuremath{\alpha}}}$. laminar traffic flow (uncongested flow) congested increasing density p