scholarly journals A macroscopic traffic model for traffic flow harmonization

2018 ◽  
Vol 10 (2) ◽  
Author(s):  
Zawar H. Khan ◽  
T. Aaron Gulliver
Keyword(s):  
Traffic Flow ◽  
Traffic Model ◽  
Macroscopic Traffic Model

scholarly journals A Macroscopic Traffic Model based on Driver Reaction and Traffic Stimuli

2019 ◽  
Vol 9 (14) ◽  
pp. 2848 ◽  
Author(s):  
Zawar H. Khan ◽  
Waheed Imran ◽  
Sajid Azeem ◽  
Khurram S. Khattak ◽  
T. Aaron Gulliver ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Flow Model ◽  
Traffic Model ◽  
Traffic Flow Model ◽  
Velocity Constant ◽  
Model Based ◽  
Proposed Model ◽  
Macroscopic Traffic Flow ◽  
Macroscopic Traffic Model ◽  
Traffic Behavior

A new macroscopic traffic flow model is proposed, which considers driver presumption based on driver reaction and traffic stimuli. The Payne–Whitham (PW) model characterizes the traffic flow based on a velocity constant C 0 which results in unrealistic density and velocity behavior. Conversely, the proposed model characterizes traffic behavior with velocities based on the distance headway. The performance of the proposed and PW models is evaluated over a 300 m circular road for an inactive bottleneck. The results obtained show that the traffic behavior with the proposed model is more realistic.

A macroscopic traffic flow model considering the velocity difference between adjacent vehicles on uphill and downhill slopes

2020 ◽  
Vol 34 (21) ◽  
pp. 2050217
Author(s):  
Peng Zhang ◽  
Yu Xue ◽  
Yi-Cai Zhang ◽  
Xue Wang ◽  
Bing-Lin Cen
Keyword(s):  
Traffic Flow ◽  
Kdv Equation ◽  
Density Wave ◽  
Traffic Model ◽  
Neutral Stability ◽  
Density Waves ◽  
Unstable Region ◽  
Velocity Difference ◽  
Macroscopic Traffic Model ◽  
The Stability

In this paper, we deduced a macroscopic traffic model on the uphill and downhill slopes by employing the transformation relation from microscopic variables to macroscopic ones based on a microscopic car-following model considering the velocity difference between adjacent vehicles. The angle [Formula: see text] of the uphill and downhill and the gravitational force have a great impact upon the stability of traffic flow. The linear stability analysis for macroscopic traffic model yielded the stability condition. The Korteweg–de Vries (KdV) equation is derived by nonlinear analysis and the corresponding solution to the density wave near the neutral stability line is obtained. By using the upwind finite difference scheme for simulation, the spatiotemporal evolution patterns of traffic flow on the uphill and downhill are attained. The unstable region is shrunken with slope of the gradient increasing and backward-traveling density waves gradually decrease and even disappear on uphill. Conversely, the unstable region on downhill is extended and density waves propagate quickly backward to the whole road with slope of the gradient increasing.

Research and Improvement of the Keep-Right-Except-to-Pass Rule

2014 ◽  
Vol 915-916 ◽  
pp. 459-463
Author(s):  
He Quan Zhang
Keyword(s):  
Fluid Mechanics ◽  
Traffic Flow ◽  
Influence Factors ◽  
Traffic Model ◽  
Light Traffic ◽  
The Road ◽  
Model Based ◽  
Light Passing ◽  
Improved Model ◽  
The Impact

In order to deal with the impact on traffic flow of the rule, we compare the influence factors of traffic flow (passing, etc.) into viscous resistance of fluid mechanics, and establish a traffic model based on fluid mechanics. First, in heavy and light traffic, we respectively use this model to simulate the actual segment of the road and find that when the traffic is heavy, the rule hinder the further increase in traffic. For this reason, we make further improvements to the model to obtain a fluid traffic model based on no passing and find that the improved model makes traffic flow increase significantly. Then, the improved model is applied to the light traffic, we find there are no significant changes in traffic flow .In this regard we propose a new rule: when the traffic is light, passing is allowed, but when the traffic is heavy, passing is not allowed.

Evolvement law of a macroscopic traffic model accounting for density-dependent relaxation time

2017 ◽  
Vol 31 (31) ◽  
pp. 1750291 ◽  
Author(s):  
Yu-Qing Wang ◽  
Xing-Jian Chu ◽  
Chao-Fan Zhou ◽  
Bin Jia ◽  
Sen Lin ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Traffic Flow ◽  
Flow Model ◽  
Initial Density ◽  
Traffic Model ◽  
Traffic Flow Model ◽  
Density Dependent ◽  
Macroscopic Traffic Flow ◽  
Boundary Perturbations ◽  
Initial Density Distribution

In this paper, a modified macroscopic traffic flow model is presented. The term of the density-dependent relaxation time is introduced here. The relation between the relaxation time and the density in traffic flow is presented quantitatively. Besides, a factor R depicting varied properties of traffic flow in different traffic states is also introduced in the formulation of the model. Furthermore, the evolvement law of traffic flow with distinctly initial density distribution and boundary perturbations is emphasized.

Macroscopic traffic model for large scale urban traffic network design

2018 ◽  
Vol 80 ◽  
pp. 32-49 ◽  
Author(s):  
Elvira Thonhofer ◽  
Toni Palau ◽  
Andreas Kuhn ◽  
Stefan Jakubek ◽  
Martin Kozek
Keyword(s):  
Network Design ◽  
Large Scale ◽  
Urban Traffic ◽  
Traffic Model ◽  
Traffic Network ◽  
Urban Traffic Network ◽  
Traffic Network Design ◽  
Macroscopic Traffic Model

Theoretical analysis of a hybrid traffic model accounting for safe velocity

2017 ◽  
Vol 31 (11) ◽  
pp. 1750104 ◽  
Author(s):  
Yu-Qing Wang ◽  
Chao-Fan Zhou ◽  
Bo-Wen Yan ◽  
De-Chen Zhang ◽  
Ji-Xin Wang ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Flow Model ◽  
Local Equilibrium ◽  
Density Wave ◽  
Traffic Model ◽  
Safe Driving ◽  
Traffic Flow Model ◽  
Velocity Wave ◽  
Vehicle Velocity ◽  
Global Equilibrium

A hybrid traffic-flow model [Wang–Zhou–Yan (WZY) model] is brought out in this paper. In WZY model, the global equilibrium velocity is replaced by the local equilibrium one, which emphasizes that the modification of vehicle velocity is based on the view of safe-driving rather than the global deployment. In the view of safe-driving, the effect of drivers’ estimation is taken into account. Moreover, the linear stability of the traffic model has been performed. Furthermore, in order to test the robustness of the system, the evolvement of the density wave and the velocity wave of the traffic flow has been numerically calculated.

DANGEROUS SITUATIONS IN TWO-LANE TRAFFIC FLOW MODELS

2005 ◽  
Vol 16 (07) ◽  
pp. 1133-1148 ◽  
Author(s):  
NAJEM MOUSSA
Keyword(s):  
Traffic Flow ◽  
Traffic Model ◽  
Low Density ◽  
Inversion Point ◽  
Lane Changing ◽  
Flow Models ◽  
Car Accidents ◽  
Maximal Speed ◽  
Traffic Flow Models ◽  
The Right

This paper investigates the probability of car accidents (PCA) in two-lane traffic flow models. We introduce new conditions for the occurrence of dangerous situations (DS) caused by an unexpected lane changing vehicles. Two different lane changing rules are considered, say symmetric and asymmetric. For the symmetric rules, we investigate the influence of the Nagel–Schreckenberg parameters such as the maximal speed, the randomization probability, …, on the PCA when vehicle moves forward or changes lanes. It is found that the forward PCA is as likely as that in one-lane traffic model. As regards to lane changing, the properties of the PCA are qualitatively different from those in one-lane traffic. For the asymmetric rules, we investigate the effect of the slack parameter Δ, introduced to adjust the inversion point of lane-usage, on the PCA. Contrarily to one-lane traffic, the forward PCA in the right lane exhibits two maximums for some range of Δ; the first one is located at low density and the second at high density. The lane changing PCA from right to left is found to decrease with increase of Δ. However, no DS exist when vehicles change from left to right.

A NEW CELLULAR AUTOMATON MODEL FOR TRAFFIC FLOW WITH DIFFERENT PROBABILITY FOR DRIVERS

2007 ◽  
Vol 18 (05) ◽  
pp. 773-782 ◽  
Author(s):  
H. B. ZHU ◽  
H. X. GE ◽  
S. Q. DAI
Keyword(s):  
Cellular Automaton ◽  
Traffic Flow ◽  
Metastable State ◽  
Maximum Flow ◽  
Traffic Model ◽  
Fundamental Diagram ◽  
Density Dependent ◽  
Spontaneous Formation ◽  
Traffic Jams ◽  
Ca Model

Based on the Nagel–Schreckenberg (NaSch) model of traffic flow, a new cellular automaton (CA) traffic model is proposed to simulate microscopic traffic flow. The probability p is a variable which contains a randomly selected term for each individual driver and a density-dependent term which is the same for all drivers. When the rational probability p is obtained, the larger value of maximum flow which is close to the observed data can be reached compared with that obtained from the NaSch model. The fundamental diagram obtained by simulation shows the ability of this modified CA model to capture the essential features of traffic flow, e.g., the spontaneous formation of traffic jams and appearance of the metastable state. These indicate that the presented model is more reasonable and realistic.

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