Macroscopic Analysis of Traffic Flow Behaviour on Multilane Highways Under Heterogeneous Traffic Conditions

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.

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Novel Area Occupancy–Based Method for Passenger Car Unit Estimation on Multilane Urban Roads Under Heterogeneous Traffic Scenario

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2615-10 ◽

2017 ◽

Vol 2615 (1) ◽

pp. 82-94 ◽

Cited By ~ 4

Author(s):

Raunak Mishra ◽

Pallav Kumar ◽

Shriniwas S. Arkatkar ◽

Ashoke Kumar Sarkar ◽

Gaurang J. Joshi

Keyword(s):

Traffic Flow ◽

Performance Measure ◽

Area Ratio ◽

Heterogeneous Traffic ◽

Passenger Car ◽

Traffic Conditions ◽

Passenger Car Unit ◽

Wide Range ◽

Traffic Volumes ◽

Measure Of Performance

This research was aimed at developing an area occupancy–based method for estimating passenger car unit (PCU) values for vehicle categories under heterogeneous traffic conditions on multilane urban roads for a wide range of traffic flow levels. First, PCU values of vehicle categories were determined according to the Transport and Road Research Laboratory definition and replaced the commonly considered measure of performance speed with area occupancy using simulation. The PCU values obtained were found to be significantly different for different volume-to-capacity ratios; this result shows that the PCU value is dynamic in nature. While the dynamic nature of PCU values is well appreciated, practitioners may prefer a single set of optimized PCU values (unique for each vehicle category). Hence, a new method with a matrix solution was proposed to estimate the optimized or unique set of PCU values with area occupancy as the performance measure. To check the credibility of the proposed method, the estimated PCU values were compared from existing guidelines regulated by the Indian Roads Congress (IRC) and values estimated with the widely accepted dynamic PCU concept of speed–area ratio. Results show that the PCU values suggested by IRC and the dynamic PCU concept using the speed–area ratio underestimate and overestimate the flows, respectively, at different traffic volumes. However, the values obtained with the area-occupancy concept were found to be consistent with the traffic flow in a cars-only traffic situation at different flow conditions. The derived set of optimized PCU values proposed can be useful for traffic engineers, researchers, and practitioners for capacity and level-of-service analysis under heterogeneous traffic conditions.

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Capacity Estimation of Multilane Highways under Heterogeneous Traffic Conditions using Micro-Simulation Technique

SAMRIDDHI A Journal of Physical Sciences Engineering and Technology ◽

10.18090/samriddhi.v12i01.4 ◽

2020 ◽

Vol 12 (01) ◽

pp. 20-25

Author(s):

Tanumoy Ghosh ◽

Sudip Kumar Roy ◽

Subhamay Gangopadhyay

Keyword(s):

Simulation Model ◽

Traffic Flow ◽

Flow Characteristics ◽

Simulation Models ◽

Heterogeneous Traffic ◽

Traffic Condition ◽

Traffic Conditions ◽

Geometric Conditions ◽

Micro Simulation ◽

Traffic Flow Characteristics

The behavior of a driver of any vehicle is important in estimating heterogeneous traffic conditions with no strict lane discipline. In the present study, a micro-simulation model is used to analyze the mixed traffic condition with different drivers’ behavior parameters. The field data collected on traffic flow characteristics of multilane highways are used in the calibration and validation of the simulation model. Out of the ten coefficient of correlation (CC) parameters in the simulation model, five are used in the present study to make a model of simulation for heterogeneous traffic; the other five parameters are not considered for testing their influence on simulated capacity values as they represent very typical behavior of a driver, either in car-following, or in free-flow conditions. Two separate simulation models are made by changing the CC (CC0, CC1, CC2, CC7, and CC8) parameters, each for a four-lane divided and a six-lane divided highway as the geometric conditions of the roads and the traffic flow is different for both the cases. These models are then applied on two other sections of a four-lane divided and a six-lane divided highway to validate the parameters of the model developed earlier for other sections.

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Modelling vehicular behaviour using trajectory data under non-lane based heterogeneous traffic conditions

Archives of Transport ◽

10.5604/01.3001.0014.0211 ◽

2019 ◽

Vol 52 (4) ◽

pp. 95-108 ◽

Cited By ~ 1

Author(s):

Hari Krishna Gaddam ◽

K. Ramachandra Rao

Keyword(s):

Traffic Flow ◽

Fast Moving ◽

Frictional Resistance ◽

Separation Distance ◽

Heterogeneous Traffic ◽

Trajectory Data ◽

Traffic Conditions ◽

Moving Vehicles ◽

Slow Moving ◽

Lane Based

The present study aims to understand the interaction between different vehicle classes using various vehicle attributes and thereby obtain useful parameters for modelling traffic flow under non-lane based heterogeneous traffic conditions. To achieve this, a separate coordinate system has been developed to extract relevant data from vehicle trajectories. Statistical analysis results show that bi-modal and multi-modal distributions are accurate in representing vehicle lateral placement behaviour. These distributions help in improving the accuracy of microscopic simulation models in predicting vehicle lateral placement on carriageway. Vehicles off-centeredness behaviour with their leaders have significant impact on safe longitudinal headways which results in increasing vehicular density and capacity of roadway. Another interesting finding is that frictional clearance distance between vehicles influence their passing speed. Analysis revealed that the passing speeds of the fast moving vehicles such as cars are greatly affected by the presence of slow moving vehicles. However, slow moving vehicles does not reduce their speeds in the presence of fast moving vehicles. It is also found that gap sizes accepted by different vehicle classes are distributed according to Weibull, lognormal and 3 parameter log logistic distributions. Based on empirical observations, the study proposed a modified lateral separation distance factor and frictional resistance factor to model the non-lane heterogeneous traffic flow at macro level. It is anticipated that the outcomes of this study would help in developing a new methodology for modelling non-lane based heterogeneous traffic.

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Development of Simple Exponential Smoothing Model for Traffic Flow Prediction under Heterogeneous Traffic Conditions

Urbanization Challenges in Emerging Economies ◽

10.1061/9780784482025.067 ◽

2018 ◽

Author(s):

G. Omkar ◽

S. Vasantha Kumar

Keyword(s):

Traffic Flow ◽

Exponential Smoothing ◽

Heterogeneous Traffic ◽

Traffic Flow Prediction ◽

Traffic Conditions ◽

Flow Prediction ◽

Simple Exponential Smoothing

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Homogeneous and Heterogenious Traffic Conditions Modellingof A Route Choice Network System

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1168.0882s819 ◽

2019 ◽

Vol 8 (2S8) ◽

pp. 1853-1857

Keyword(s):

Traffic Flow ◽

Transportation Systems ◽

Heterogeneous Traffic ◽

Network System ◽

Rectangular Grid ◽

Traffic Flow Theory ◽

Human Control ◽

Traffic Conditions ◽

The Mean ◽

Vehicle Fleet

Demonstrating course decision conduct is dangerous, yet basic to evaluate explorers' impression of course attributes, to estimate voyagers' conduct under theoretical situations, to anticipate Future site visitors situations on transportation systems and to comprehend voyagers' response and adjustment to wellsprings of information. We increase a perceptible heterogeneous traffic flow version. This version considers trade of various vehicle lessons, each one of that's anticipated to have homogeneous vehicle following conduct and automobile trends. We advocate the thoughts of road restrict break up and saw same thickness for every elegance to expose both horizontal and longitudinal go-class collaborations crosswise over neighboring cells. Instead of making use of hydrodynamic analogies, it builds up sensible go-class verbal exchange concepts sought through restrict distribution and surmised between mobile motions. The congestion phenomenon is considered in desk bound situations via the conduct ofamounts: the suggest tour time of a parcel and the mean quantity of bundles that have no longer arrived at their cause and are travel-ing in the system. We characterize a exchange that maps a gadget having the little global belongings (Inet 3037 in our numerical examinations) into an (altered) grid arrange that has a comparable range of hubs. This guide adjustments the restrict of the additives of the charts speakme to the systems and can be considered as an "interjection" among the two instructions of systems. Utilizing this change we evaluation the conduct of Inet 3037 with the behavior of an altered rectangular grid and we have a look at the conduct of the placing systems. This examination recommends the way to alternate the system topology and the department limits so that it will mitigate the congestion phenomenon.Understanding the causes and dynamics of nonequilibrium traffic flow via models, observations, and data is a crucial challenge in traffic flow theory; and it becomes even more important in light of ongoing and future (partial) automation of the vehicle fleet. We highlight important steps in developing phenomenological models for instabilities and nonlinear waves in traffic flow, both macroscopic and microscopic, and discuss how this modeling extends to heterogeneous flows composed of a mix of human-driven and (semi-)automated vehicles. In particular, we stress how automation can go both ways: it could make traffic run more smoothly; but also render it less efficient than it is under human control

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Travel Time Reliability of Bus Operation in Heterogeneous Traffic Conditions of Dar es Salaam City, Tanzania

LOGI – Scientific Journal on Transport and Logistics ◽

10.2478/logi-2020-0014 ◽

2020 ◽

Vol 11 (2) ◽

pp. 44-55

Author(s):

Prosper S. Nyaki ◽

Hannibal Bwire ◽

Nurdin K. Mushule

Keyword(s):

Travel Time ◽

Traffic Flow ◽

Traffic Congestion ◽

Dar Es Salaam ◽

Heterogeneous Traffic ◽

Service Reliability ◽

Travel Time Reliability ◽

Activity Scheduling ◽

Traffic Conditions ◽

Deviation Coefficient

AbstractThe assessment of travel time reliability enables precise prediction of travel times, better activity scheduling and decisions for all users of the road network. Furthermore, it helps to monitor traffic flow as a crucial strategy for reducing traffic congestion and ensuring high-quality service in urban roads. Travel time reliability is a useful reference tool for evaluating transport service quality, operating costs and system efficiency. However, many analyses of travel time reliability do not provide true travel variation under heterogeneous traffic flow conditions where traffic flow is a mixture of motorized and non-motorized transport. This study analysed travel time reliability under heterogeneous traffic conditions. The travel reliabilities focused on passenger waiting time at bus stops, in-vehicle travel time, and delay time at intersections which were analysed using buffer time, standard deviation, coefficient of variation, and planning time. The data used were obtained from five main bus routes in Dar es Salaam. The results indicate low service reliability in the outbound directions compared to inbound directions. They also intend to raise awareness of policy-makers about the situation and to make them shift from expanding road networks towards optimising road operations.

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Smart Driving System for Improving Traffic Flow

International Journal of Advanced Research in Computer Science and Software Engineering ◽

10.23956/ijarcsse/v7i7/0174 ◽

2017 ◽

Vol 7 (7) ◽

pp. 236

Author(s):

Rajesh Kumar Gupta ◽

L. N. Padhy ◽

Sanjay Kumar Padhi

Keyword(s):

Traffic Flow ◽

Traffic Congestion ◽

Urban Areas ◽

Adaptive Cruise Control ◽

Human Perception ◽

Cruise Control ◽

Driving System ◽

V2v Communication ◽

Traffic Conditions ◽

Cooperative Adaptive Cruise Control

Traffic congestion on road networks is one of the most significant problems that is faced in almost all urban areas. Driving under traffic congestion compels frequent idling, acceleration, and braking, which increase energy consumption and wear and tear on vehicles. By efficiently maneuvering vehicles, traffic flow can be improved. An Adaptive Cruise Control (ACC) system in a car automatically detects its leading vehicle and adjusts the headway by using both the throttle and the brake. Conventional ACC systems are not suitable in congested traffic conditions due to their response delay. For this purpose, development of smart technologies that contribute to improved traffic flow, throughput and safety is needed. In today’s traffic, to achieve the safe inter-vehicle distance, improve safety, avoid congestion and the limited human perception of traffic conditions and human reaction characteristics constrains should be analyzed. In addition, erroneous human driving conditions may generate shockwaves in addition which causes traffic flow instabilities. In this paper to achieve inter-vehicle distance and improved throughput, we consider Cooperative Adaptive Cruise Control (CACC) system. CACC is then implemented in Smart Driving System. For better Performance, wireless communication is used to exchange Information of individual vehicle. By introducing vehicle to vehicle (V2V) communication and vehicle to roadside infrastructure (V2R) communications, the vehicle gets information not only from its previous and following vehicle but also from the vehicles in front of the previous Vehicle and following vehicle. This enables a vehicle to follow its predecessor at a closer distance under tighter control.

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