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Based on the common existence of the mixed road, a switched controller with consideration of the difference between estimation optimal and current flux (EOCFD) is presented in the lattice hydrodynamic model of traffic flow. Based on the Hurwitz criteria and the H ∞ -norm, stability conditions for the curved road and straight road scenarios are obtained with the transfer functions G 0 and G 1 respectively. By analyzing the Bode-plot of transfer functions G 0 and G 1 , stability analysis is performed with the feedback gain k, the radian θ j and the curvature radius R. These theoretical results indicate that the switched control scheme prompts the traffic flow to be more stable in both curved and straight roads. Compared with Cheng's model, numerical simulations with multiple perturbations confirm that the switched control scheme can further suppress the traffic congestion with a lower feedback gain on mixed road.INDEX TERMS Switched control, mixed road, lattice hydrodynamic model, traffic flow.

Extensive hot-wire anemometer measurements have been carried out in a at plate boundary layer undergoing transition from laminar to fully turbulent ow. The main aim of the present work is to develop a convenient and objective method which can be applied to streamwise velocity uctuations to obtain distributions of the turbulence intermittency factor across the boundary layer in the transition region. For this purpose, based on the M-TERA (Modiÿed Turbulent Energy Recognition Algorithm) method, an envelope method, called EM-TERA, employing two detection criteria for detection of turbulence intermittency, is proposed. The results indicate that this method can detect the turbulence intermittency conveniently and reliably with its two respective threshold coe cients kept constant (C 1 = 0:5 and C2 = 0:01) in the entire transitional region of a boundary layer, except for the very near-wall region.

To prevent traffic congestion, drivers always adjust the driving behavior with their driving information. By considering the self-anticipation effect and the optimal current difference effect on traffic flow stability, a novel two-lane lattice hydrodynamic model is proposed. Compared with Peng’s model, the linear stability analysis results reveal that the self-anticipation term can effectively enlarge the stable region on the phase diagram. Then, a reductive perturbation method is used to derive the mKdV equation describing traffic congestion near the critical point. Nonlinear analyses show that the traffic congestions can be effectively suppressed by taking the coefficient of lane-changing behaviors γ and the anticipation time τ into account. These results further indicate that the driver’s self-anticipation current difference effect can efficiently alleviate traffic jams. Furthermore, the numerical simulations with periodic boundary conditions also confirm the effectiveness of theoretical results.

In order to prevent the occurrence of traffic accidents, drivers always focus on the running conditions of the preceding and rear vehicles to change their driving behavior. By taking into the “backward-looking” effect and the driver’s anticipation effect of flux difference consideration at the same time, a novel two-lane lattice hydrodynamic model is proposed to reveal driving characteristics. The corresponding stability conditions are derived through a linear stability analysis. Then, the nonlinear theory is also applied to derive the mKdV equation describing traffic congestion near the critical point. Linear and nonlinear analyses of the proposed model show that how the “backward-looking” effect and the driver’s anticipation behavior comprehensively affect the traffic flow stability. The results show that the positive constant γ , the driver’s anticipation time τ , and the sensitivity coefficient p play significant roles in the improvement of traffic flow stability and the alleviation of the traffic congestion. Furthermore, the effectiveness of linear stability analysis and nonlinear analysis results is demonstrated by numerical simulations.