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Optimal velocity difference model for a car-following theory 总被引:1,自引:0,他引:1
In this Letter, we present a new optimal velocity difference model for a car-following theory based on the full velocity difference model. The linear stability condition of the new model is obtained by using the linear stability theory. The unrealistically high deceleration does not appear in OVDM. Numerical simulation of traffic dynamics shows that the new model can avoid the disadvantage of negative velocity occurred at small sensitivity coefficient λ in full velocity difference model by adjusting the coefficient of the optimal velocity difference, which shows that collision can disappear in the improved model. 相似文献
3.
The stability analysis is one of the important problems in the traffic flow theory, since the congestion phenomena can be regarded as the instability and the phase transition of a dynamical system. Theoretically, we analyze the stable conditions of the full velocity and acceleration difference model (FVADM), which is proposed by introducing the acceleration difference term based on the previous car-following models (the optimal velocity model and the full velocity difference model, OVM and FVDM). By numerical simulations, it is found that when the traffic flow is unstable, the traffic jam in the FVADM is weaker than that in the FVDM. Also it is observed that the spreading speed of the jam is slower in the FVADM than that in the FVDM and the fluctuations of vehicles in the FVADM are smaller than those in the FVDM. Therefore, the acceleration difference term has strong effects on traffic dynamics and plays an important role in stabilizing the traffic flow. 相似文献
4.
Z.-P. Li Y.-C. Liu 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,53(3):367-374
By introducing relative velocities of arbitrary number of
cars ahead into the full velocity difference models (FVDM), we
present a forward looking relative velocity model (FLRVM) of
cooperative driving control system. To our knowledge, the model is
an improvement over the similar extension in the forward looking
optimal velocity models (FLOVM), because it is more reasonable and
realistic in implement of incorporating intelligent transportation
system in traffic. Then the stability criterion is investigated by
the linear stability analysis with finding that new consideration
theoretically lead to the improvement of the stability of traffic
flow, and the validity of our theoretical analysis is confirmed by
direct simulations. In addition, nonlinear analysis of the model
shows that the three waves: triangular shock wave, soliton wave and
kink-antikink wave appear respectively in stable, metastable and
unstable regions. These correspond to the solutions of the Burgers
equation, Korteweg-de Vries (KdV) equation and modified Korteweg-de
Vries (mKdV) equation. 相似文献
5.
The full velocity difference model proposed by Jiang et
al. [2001 Phys. Rev. E 64 017101] has been improved
by introducing velocity anticipation. Velocity anticipation means
the follower estimates the future velocity of the leader. The
stability condition of the new model is obtained by using the linear
stability theory. Theoretical results show that the stability region
increases when we increase the anticipation time interval. The mKdV
equation is derived to describe the kink--antikink soliton wave and
obtain the coexisting stability line. The delay time of car motion
and kinematic wave speed at jam density are obtained in this model.
Numerical simulations exhibit that when we increase the anticipation
time interval enough, the new model could avoid accidents under
urgent braking cases. Also, the traffic jam could be suppressed by
considering the anticipation velocity. All results demonstrate that
this model is an improvement on the full velocity difference model. 相似文献
6.
By introducing the traffic anticipation effect in the real world into the original lattice hydrodynamic model, we present a new anticipation effect lattice hydrodynamic (AELH) model, and obtain the linear stability condition of the model by applying the linear stability theory. Through nonlinear analysis, we derive the Burgers equation and Korteweg-de Vries (KdV) equation, to describe the propagating behaviour of traffic density waves in the stable and the metastable regions, respectively. The good agreement between simulation results and analytical results shows that the stability of traffic flow can be enhanced when the anticipation effect is considered. 相似文献
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8.
On the basis of the full velocity difference (FVD) model,
an improved multiple car-following (MCF) model is proposed by taking
into account multiple information inputs from preceding vehicles.
The linear stability condition of the model is obtained by using the
linear stability theory. Through nonlinear analysis, a modified
Korteweg-de Vries equation is constructed and solved. The traffic
jam can thus be described by the kink--antikink soliton solution for
the mKdV equation. The improvement of this new model over the
previous ones lies in the fact that it not only theoretically retains many
strong points of the previous ones, but also performs more
realistically than others in the dynamical evolution of congestion.
Furthermore, numerical simulation of traffic dynamics shows that the
proposed model can avoid the disadvantage of negative velocity that
occurs at small sensitivity coefficients λ in the FVD model by
adjusting the information on the multiple leading vehicles. No
collision occurs and no unrealistic deceleration appears in the
improved model. 相似文献
9.
In this paper, a new lattice hydrodynamic traffic flow model is proposed by considering the driver’s anticipation effect in sensing relative flux (DAESRF) for two-lane system. The effect of anticipation parameter on the stability of traffic flow is examined through linear stability analysis and shown that the anticipation term can significantly enlarge the stability region on the phase diagram. To describe the phase transition of traffic flow, mKdV equation near the critical point is derived through nonlinear analysis. The theoretical findings have been verified using numerical simulation which confirms that traffic jam can be suppressed efficiently by considering the anticipation effect in the new lattice model for two-lane traffic. 相似文献
10.
A new lattice hydrodynamic traffic flow model with a consideration of multi-anticipation effect 总被引:1,自引:0,他引:1
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We present a new multi-anticipation lattice hydrodynamic model based on the traffic anticipation effect in the real world.Applying the linear stability theory,we obtain the linear stability condition of the model.Through nonlinear analysis,we derive the modified Korteweg-de Vries equation to describe the propagating behaviour of a traffic density wave near the critical point.The good agreement between the simulation results and the analytical results shows that the stability of traffic flow can be enhanced when the multi-anticipation effect is considered. 相似文献
11.
The optimal driving speeds of the different vehicles may be different for the same headway. In the optimal velocity function of the optimal velocity (OV) model, the maximum speed is an important parameter determining the optimal driving speed. A vehicle with higher maximum speed is more willing to drive faster than that with lower maximum speed in similar situation. By incorporating the anticipation driving behavior of relative velocity and mixed maximum speeds of different percentages into optimal velocity function, an extended heterogeneous car-following model is presented in this paper. The analytical linear stable condition for this extended heterogeneous traffic model is obtained by using linear stability theory. Numerical simulations are carried out to explore the complex phenomenon resulted from the cooperation between anticipation driving behavior and heterogeneous maximum speeds in the optimal velocity function. The analytical and numerical results all demonstrate that strengthening driver's anticipation effect can improve the stability of heterogeneous traffic flow, and increasing the lowest value in the mixed maximum speeds will result in more instability, but increasing the value or proportion of the part already having higher maximum speed will cause different stabilities at high or low traffic densities. 相似文献
12.
A new lattice model of traffic flow is presented by taking into account the anticipation of potential lane changing on front site on single lane. The stability condition of the extended model is obtained by using the linear stability theory. The modified KdV equation near the critical point is constructed and solved through nonlinear analysis. And the phase space of traffic flow in the density-sensitivity space could be divided into three regions: stable, metastable and unstable ones, respectively. Numerical simulation also shows that the consideration of lane changing probability in lattice model can stabilize traffic flow, which implies that the new consideration has an important effect on traffic flow in lattice models. 相似文献
13.
By introducing acceleration difference terms into the
full velocity difference models (FVDM) by Jiang et al. (1995), we present a full velocity
and acceleration difference model (FVADM). The main improvement upon the
previous models is that the FVADM can exactly describe the driver’s behavior
under an urgent case, where no collision occurs and no unrealistic
deceleration appears in this model, while vehicles determined by the
previous car-following models collide after only few seconds. The model is
investigated by numerical methods. The simulation results indicate that the
acceleration difference has an important impact on the traffic dynamics,
especially under urgent conditions. Besides the urgent situations, the model
still remains similar properties to those of the FVDM. In the model, the
phase transition of traffic flow is observed, and the hysteresis loop is
obtained in the headway- velocity plane, also. 相似文献
14.
G.H. Peng 《Physica A》2012
In this paper, a new lattice model of traffic flow is proposed to investigate wide moving jams in traffic flow with the consideration of the driver anticipation information about two preceding sites. The linear stability condition is obtained by using linear stability analysis. The mKdV equation is derived through nonlinear analysis, which can be conceivably taken as an approximation to a wide moving jam. Numerical simulation also confirms that the congested traffic patterns about wide moving jam propagation in accordance with empirical results can be suppressed efficiently by taking the driver anticipation effect of two preceding sites into account in a new lattice model. 相似文献
15.
In this paper, a new lattice hydrodynamic model is proposed by incorporating the driver anticipation effect of next-nearest-neighbor site. The linear stability analysis and nonlinear analysis show that the driver anticipation effect of next-nearest-neighbor site can enlarge the stable area of traffic flow. The space can be divided into three regions: stable, metastable, and unstable. Numerical simulation further illuminates that the driver anticipation effect of the next-nearest-neighbor site can stabilize traffic flow in our modified lattice model, which is consistent with the analytical results. 相似文献
16.
Nonlinear density wave and energy consumption investigation of traffic flow on a curved road
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A new car-following model is proposed based on the full velocity difference model(FVDM) taking the influence of the friction coefficient and the road curvature into account. Through the control theory, the stability conditions are obtained,and by using nonlinear analysis, the time-dependent Ginzburg-Landau(TDGL) equation and the modified Korteweg-de Vries(mKdV) equation are derived. Furthermore, the connection between TDGL and mKdV equations is also given. The numerical simulation is consistent with the theoretical analysis. The evolution of a traffic jam and the corresponding energy consumption are explored. The numerical results show that the control scheme is effective not only to suppress the traffic jam but also to reduce the energy consumption. 相似文献
17.
A feedback control model of lattice hydrodynamic model is proposed by taking the information of the historic optimal velocity into account for the traffic system. The modern control theory is applied for the linear stability condition with feedback control signal. The result shows that the stability of traffic flow is closely related to the information of the historic optimal velocity. Furthermore, numerical simulations conform that the new feedback control did increase the stability of traffic flow efficiently, which is in accord with theoretical analysis. 相似文献
18.
An improved multiple car-following model is proposed by
considering the arbitrary number of preceding cars, which includes
both the headway and the velocity difference of multiple preceding
cars. The stability condition of the extended model is obtained by
using the linear stability theory. The modified Korteweg--de Vries
equation is derived to describe the traffic behaviour near the
critical point by applying the nonlinear analysis. Traffic flow can
be also divided into three regions: stable, metastable and unstable
regions. Numerical simulation is accordance with the analytical
result for the model. And numerical simulation shows that the
stabilisation of traffic is increasing by considering the
information of more leading cars and there is unavoidable effect on
traffic flow from the multiple leading cars' information. 相似文献
19.
Based on the velocity gradient model, an extended continuum model with consideration of the mean-field velocity difference is proposed in this paper. By using the linear stability theory, the linear stability criterion of the new model is gained, which proved that mean-field velocity difference has significant influence on stability of traffic flow. The KdV–Burgers equation is derived by using non-linear analysis method and the evolution of density wave near the neutral stability line is explored. Numerical simulations are carried out how mean-field velocity difference affect the stability of traffic flow, and energy consumption is also studied for this new macro model. At the same time, complicated traffic phenomena such as local cluster effects, shock waves and rarefaction waves can be reproduced in the new model by numerical simulation. Numerical results are consistent with the theoretical analysis, which indicates that the mean-field velocity difference not only suppresses traffic jam, but also depresses energy consumption. 相似文献
20.
A one-dimensional cellular automaton model of
traffic flow is proposed
to introduce the different delay probabilities in the steps of rules and
the stochastic deceleration prior to the deterministic one when the
anticipation velocity of vehicle is larger than the headway.
The fundamental diagram shows the capacity of road more approaches
to the observed data compared with that by the NaSch model. Moreover,
the model is able to reproduce the complicated behavior of the real traffic,
such as the metastability state, the separation of different phases and the
effect of hysteresis. It is concluded that the order arrangement of the
stochastic deceleration and deterministic acceleration has indeed
remarkable effect on traffic flow and the modification presented in
this paper is reasonable and realistic. 相似文献