Gas-Kinetic Traffic Flow Modeling Including Continuous Driver Behavior Models

2003 ◽  
Vol 1852 (1) ◽  
pp. 231-238 ◽  
Author(s):  
C. M. J. Tampère ◽  
B. van Arem ◽  
S. P. Hoogendoorn
Keyword(s):  
Traffic Flow ◽  
Driver Behavior ◽  
Discrete Event ◽  
Traffic Density ◽  
Flow Density ◽  
Flow Equations ◽  
Flow Models ◽  
Explanatory Factors ◽  
Traffic Flow Models ◽  
Car Following Model

A modeling technique is presented that analytically bridges the gap between microscopic behavior of individual drivers and the macroscopic dynamics of traffic flow. The basis of this approach is the (gas-) kinetic or mesoscopic modeling principle that considers the dynamics of traffic density and generalizations thereof as a probability density function of vehicles in different driving states. In contrast to traditional kinetic models, deceleration of individual vehicles due to slower traffic is treated as a continuous adaptive process rather than a discrete event. An analytic procedure is proposed to aggregate arbitrarily refined individual driver behavior to a macroscopic expected acceleration or deceleration of flow as a whole that can be used in macroscopic differential equations for traffic flow. The procedure implicitly accounts for the anisotropy of information flow in traffic, for anticipation behavior of drivers, and for the finite space requirement of vehicles, as long as these properties have been specified at the level of individual driver behavior. The procedure is illustrated for a simple car-following model with overtaking opportunity. The results show that the procedure yields micro-based aggregate traffic flow models that capture the essential properties of traffic dynamics. The techniques presented can contribute to the development of traffic flow models with driver behavior and driver psychology as important explanatory factors of congestion formation and propagation. Moreover, the approach allows building macroscopic traffic flow equations from future traffic flows for which no empirical speed–flow–density relations are available yet.

scholarly journals Effects of static bottlenecks on traffic flow in urban road network

2020 ◽  
Vol 12 (3) ◽  
pp. 1-15
Author(s):  
John N.P. Mahona ◽  
Cuthbert F. Mhilu ◽  
Joseph Kihedu ◽  
Hannibal Bwire
Keyword(s):  
Traffic Flow ◽  
Road Network ◽  
Traffic Density ◽  
Urban Road Network ◽  
Peak Period ◽  
Flow Models ◽  
Urban Road ◽  
Stop And Go ◽  
Traffic Flow Models ◽  
Methodological Aspects

Existing traffic flow models do not consider the effects of road static bottlenecks on traffic flow. In this paper, a modified macroscopic continuum  model for traffic flow on urban road network with static bottlenecks is presented. The model takes into account the fluctuations of traffic flow considering static bottlenecks during the morning peak period. The model results show that existence of static road bottlenecks with various configurations cause traffic flow instabilities. This phenomenon lead into stop-and-go traffic flow conditions under the moderate density and reduction of the traffic system’s efficiency. Furthermore, results show that an increase in traffic density is accompanied by a significant decrease of speed which adversely influences performance of roadway and decrease the traffic system’s efficiency and thus resulting to the occurrence of congestions. The methodological aspects of the study and results will enable traffic engineers and planners to assess and improve existing urbanroad networks. Keywords: Traffic flow, Bottlenecks, stability, Stop-and-go traffic, System’s efficiency, Congestion.

Modelling Heterogeneous and Undisciplined Traffic Flow using Cell Transmission Model

2020 ◽  
Vol 02 (01) ◽  
pp. 01-05
Author(s):  
Afzal Ahmed ◽  
Mir Shabbar Ali ◽  
Toor Ansari
Keyword(s):  
Traffic Flow ◽  
Traffic Simulation ◽  
Flow Diagram ◽  
Transmission Model ◽  
Flow Density ◽  
Cell Transmission Model ◽  
Flow Models ◽  
Simulation And Optimization ◽  
Cell Transmission ◽  
Traffic Flow Models

This research calibrates Cell Transmission Model (CTM) for heterogeneous and non-lane disciplined traffic, as observed in Pakistan and some other developing countries by constructing a flow-density fundamental traffic flow diagram. Currently, most of the traffic simulation packages used for such heterogonous and non-lane-disciplined traffic are not calibrated for local traffic conditions and most of the traffic flow models are developed for comparatively less heterogeneous and lane-disciplined traffic. The flow-density fundamental traffic flow diagram is developed based on extensive field data collected from Karachi, Pakistan. The calibrated CTM model is validated by using actual data from another road and it was concluded that CTM is capable of modelling heterogeneous and non-lane disciplined traffic and performed very reasonably. The calibrated CTM will be a useful input for the application of traffic simulation and optimization packages such as TRANSYT, SIGMIX, DISCO, and CTMSIM.

Width-Based Cell Transmission Model for Heterogeneous and Undisciplined Traffic Streams

2019 ◽  
Vol 2673 (5) ◽  
pp. 682-692 ◽  
Author(s):  
Afzal Ahmed ◽  
Satish V. Ukkusuri ◽  
Shahrukh Raza Mirza ◽  
Ausaja Hassan
Keyword(s):  
Traffic Flow ◽  
Behavior Modeling ◽  
Flow Diagram ◽  
Transmission Model ◽  
Flow Density ◽  
Cell Transmission Model ◽  
Fundamental Diagram ◽  
Flow Models ◽  
Cell Transmission ◽  
Traffic Flow Models

Traffic streams in many developing countries consist of various modes of transport, with high heterogeneity in driver behavior. Modeling these types of traffic streams, in which traffic rules (speed limit, lane discipline, etc.) are not strictly followed, is a complex task. A review of the existing literature shows that there is a lack of traffic flow models that model the behavior of heterogeneous and undisciplined traffic streams. Like other undisciplined traffic streams, there are no speed limits (hence no speed enforcement) on most of the roads in Karachi, Pakistan. Lane discipline is also not observed by drivers, which results in a varying number of traffic lanes on a road. Therefore, most of the existing traffic flow models/simulation packages developed for disciplined traffic streams cannot appropriately model traffic streams without lane discipline. This research proposes a width-based cell transmission model (WCTM) by developing a fundamental flow-density diagram whose parameters are a function of the road width. Extensive field data have been collected from a selected arterial in Karachi for development of the fundamental traffic flow diagram. The values of the computed parameters are significantly different than the values reported in the literature. The piecewise-linear flow-density relation is developed by optimally estimating the breakpoints. Results show that the quadrilateral and pentagonal-shaped fundamental diagrams fit better with the collected data in comparison with the triangular-shaped fundamental diagram. The proposed WCTM is applied to selected segments of an arterial and results show that the WCTM was able to accurately model different traffic conditions.

scholarly journals Macroscopic Traffic Flow Characterization at Bottlenecks

2020 ◽  
Vol 6 (7) ◽  
pp. 1227-1242
Author(s):  
Amir Iftikhar ◽  
Zawar H. Khan ◽  
T. Aaron Gulliver ◽  
Khurram S. Khattak ◽  
Mushtaq A. Khan ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Traffic Congestion ◽  
Urban Areas ◽  
Driver Behavior ◽  
Flow Models ◽  
Driver Response ◽  
Lwr Model ◽  
Upwind Difference Scheme ◽  
Flow Characterization ◽  
Traffic Flow Models

Traffic congestion is a significant issue in urban areas. Realistic traffic flow models are crucial for understanding and mitigating congestion. Congestion occurs at bottlenecks where large changes in density occur. In this paper, a traffic flow model is proposed which characterizes traffic at the egress and ingress to bottlenecks. This model is based on driver response which includes driver reaction and traffic stimuli. Driver reaction is based on time headway and driver behavior which can be classified as sluggish, typical or aggressive. Traffic stimuli are affected by the transition width and changes in the equilibrium velocity distribution. The explicit upwind difference scheme is used to evaluate the Lighthill, Whitham, and Richards (LWR) and proposed models with a continuous injection of traffic into the system. A stability analysis of these models is given and both are evaluated over a road of length 10 km which has a bottleneck. The results obtained show that the behavior with the proposed model is more realistic than with the LWR model. This is because the LWR model cannot adequately characterize driver behavior during changes in traffic flow.

Stochastic Traffic Flow Models of the National Airspace System

2008 ◽  
Author(s):  
Monish Tandale ◽  
Jinwhan Kim ◽  
Karthik Palaniappan ◽  
P. K. Menon ◽  
Jay Rosenberger ◽  
...  
Keyword(s):  
Traffic Flow ◽  
National Airspace System ◽  
Flow Models ◽  
Traffic Flow Models

Study of the Response of PW Traffic Flow Model to a Bottleneck on a Circular Road and its Suitability for Heterogeneous Traffic Conditions

2021 ◽  
Vol 9 (4) ◽  
pp. 460-463
Keyword(s):  
Fluid Flow ◽  
Traffic Flow ◽  
Flow Model ◽  
Equation Model ◽  
Heterogeneous Traffic ◽  
Flow Conditions ◽  
Flow Models ◽  
Traffic Conditions ◽  
Model Response ◽  
Traffic Flow Models

The traffic flow conditions in developing countries are predominantly heterogeneous. The early developed traffic flow models have been derived from fluid flow to capture the behavior of the traffic. The very first two-equation model derived from fluid flow is known as the Payne-Whitham or PW Model. Along with the traffic flow, this model also captures the traffic acceleration. However, the PW model adopts a constant driver behavior which cannot be ignored, especially in the situation of heterogeneous traffic.This research focuses on testing the PW model and its suitability for heterogeneous traffic conditions by observing the model response to a bottleneck on a circular road. The PW model is mathematically approximated using the Roe Decomposition and then the performance of the model is observed using simulations.

scholarly journals Weakly nonlinear analysis for car-following model with consideration of cooperation and time delays

2018 ◽  
Vol 32 (21) ◽  
pp. 1850241 ◽  
Author(s):  
Dong Chen ◽  
Dihua Sun ◽  
Min Zhao ◽  
Yuchu He ◽  
Hui Liu
Keyword(s):  
Traffic Flow ◽  
Linear Stability ◽  
Time Delays ◽  
Kdv Equation ◽  
Cooperative Behavior ◽  
Optimal Velocity ◽  
Flow Models ◽  
Car Following ◽  
Cooperative Driving ◽  
Car Following Model

In traffic systems, cooperative driving has attracted the researchers’ attention. A lot of works attempt to understand the effects of cooperative driving behavior and/or time delays on traffic flow dynamics for specific traffic flow models. This paper is a new attempt to investigate analyses of linear stability and weak nonlinearity for the general car-following model with consideration of cooperation and time delays. We derive linear stability condition and study how the combinations of cooperation and time delays affect the stability of traffic flow. Burgers’ equation and Korteweg de Vries’ (KdV) equation for car-following model considering cooperation and time delays are derived. Their solitary wave solutions and constraint conditions are concluded. We investigate the property of cooperative optimal velocity (OV) model which estimates the combinations of cooperation and time delays about the evolution of traffic waves using both analytic and numerical methods. The results indicate that delays and cooperation are model-dependent, and cooperative behavior could inhibit the stabilization of traffic flow. Moreover, delays of sensing relative motion are easy to trigger the traffic waves; delays of sensing host vehicle are beneficial to relieve the instability effect to a certain extent.

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