CHARACTERISTICS OF FUNDAMENTAL DIAGRAMS DUE TO SHOCKWAVE BY NON-LANE BASED HETEROGENEOUS TRAFFIC

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Abu Jar Md. Minhuz Uddin Ahmed ◽  
Md. Tarek Hasan ◽  
Md. Rakibul Alam ◽  
Md. Shamsul Hoque
Keyword(s):  
Traffic Flow ◽  
Heterogeneous Traffic ◽  
Main Concern ◽  
Traffic Condition ◽  
Lane Changing ◽  
Global Context ◽  
Video Footage ◽  
Flow Parameters ◽  
Significant Decrement ◽  
Lane Based

If the global context of traffic flow researches are highlighted, it is observed that many researches have already been conducted with the Fundamental Diagrams of traffic flow for lane based homogeneous traffic. Studies related to propagation of shockwaves are being conducted as well. But for developing countries such as Bangladesh, it is predominant that non-lane based heterogeneous traffic exists in most of the roads. Firstly there is scarcely any lane concept among the drivers at all. Moreover frequent lane changing is a common phenomenon. For these reasons, responses of Fundamental Diagrams' shape are quite distinctive from already established shapes. Thus the main concern is to trace the deviation of the prevailing traffic flow parameters of traffic flow from those established equations. Video footage has been taken of roadway section marked suitably for measurement. Shockwaves due to lane changing for non-lane based and heterogeneous synchronized traffic flow has been accomplished and modelled using R and MATLAB analysis for a highway of Dhaka city, Bangladesh. After modeling the calibration and validation are done accordingly to distinguish the variation from ideal models and to verify that the study outcomes converge as well. It has been detected that shockwave induces significant decrement in flow and speed in case of specified traffic condition.

scholarly journals Research on Mandatory Lane-Changing Behavior in Highway Weaving Sections

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Wei Hao ◽  
Zhaolei Zhang ◽  
Zhibo Gao ◽  
Kefu Yi ◽  
Li Liu ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Traffic Accidents ◽  
Driving Behavior ◽  
Heterogeneous Traffic ◽  
Psychological Characteristics ◽  
Distribution Characteristics ◽  
Mixed Traffic ◽  
Lane Changing ◽  
Headway Distribution ◽  
Analysis Models

As the accident-prone sections and bottlenecks, highway weaving sections will become more complicated when it comes to the mixed-traffic environments with connected and automated vehicles (CAVs) and human-driven vehicles (HVs). In order to make CAVs accurately identify the driving behavior of manual-human vehicles to avoid traffic accidents caused by lane changing, it is necessary to analyze the characteristics of the mandatory lane-changing (MCL) process in the weaving area. An analytical MCL method based on the driver’s psychological characteristics is proposed in this study. Firstly, the driver’s MLC pressure concept was proposed by leading in the distance of the off-ramp. Then, the lane-changing intention was quantified by considering the driver’s MLC pressure and tendentiousness. Finally, based on the lane-changing intention and the headway distribution of the target lane, an MLC positions probability density model was proposed to describe the distribution characteristics of the lane-changing position. Through the NGSIM data verification, the lane-changing analysis models can objectively describe the vehicle lane-changing characteristics in the actual scenarios. Compared with the traditional lane-changing model, the proposed models are more interpretable and in line with the driving intention. The results show significant improvements in the lane-changing safe recognition of CAVs in heterogeneous traffic flow (both CAVs and HVs) in the future.

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

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.

The Empirical Study on the Relationships among the Times of Lane-Changing, Speed and Density of Traffic Flow - For Level of Service Two in Different Lanes of Weaving Area of Urban Expressway

2012 ◽  
Vol 209-211 ◽  
pp. 934-937
Author(s):  
Han Xie ◽  
Yang Sheng Jiang ◽  
Juan Xiu Zhu ◽  
Xi Zhao Lu
Keyword(s):  
Empirical Study ◽  
Traffic Flow ◽  
Level Of Service ◽  
Traffic Condition ◽  
Lane Changing ◽  
Urban Expressway ◽  
Statistical Relationships ◽  
The Times

This paper analyzed the statistical relationships among lane-changing, speed and density of traffic flow in different lanes of urban expressway weaving area under a given traffic condition and LOS two. A series of models was recommended. And then, the effectiveness between the recommended model and the existing model was compared. Although the optimization effect not very clear, but it shows that the lane-changing factors have some effects .

scholarly journals Characteristics of traffic flows at roundabouts in the city of Banja Luka before and during COVID-19 crisis

2021 ◽  
Vol 67 (4) ◽  
pp. 31-35
Author(s):  
Nemanja Garunovic ◽  
Vuk Bogdanović ◽  
Slavko Davidović ◽  
Valentina Mirović ◽  
Jelena Mitrović Simić
Keyword(s):  
Traffic Flow ◽  
Flow Characteristics ◽  
Traffic Condition ◽  
State Of Emergency ◽  
Flow Parameters ◽  
Pedestrian Traffic ◽  
The Difference ◽  
Banja Luka ◽  
Restrictive Measures ◽  
The City

COVID-19 pandemic caused many restrictive measures. Most of these measures were in the relationship with the restrictions of mobility which caused some differences in traffic flow demands. In this paper the comparative analysis of traffic flow characteristics at roundabouts in the City of Banja Luka was conducted. The analysis included two different states of traffic condition: the first one, normal condition before COVID-19 crisis, and the second one, during the state of emergency caused by the pandemic. The analysis shows the difference between some of motorized vehicle and pedestrian traffic flow parameters.

scholarly journals Performance of Urban Corridor Using Speed Profile Data of Automobile

2020 ◽  
Vol 3 (10) ◽  
pp. 1-8
Author(s):  
T. Vijay Kumar ◽  
Drisya Manghat ◽  
L. Geetha ◽  
Vivek R. Das
Keyword(s):  
Traffic Flow ◽  
Heterogeneous Traffic ◽  
Speed Profile ◽  
Profile Data ◽  
Mean Velocity ◽  
The Road ◽  
Flow Parameters ◽  
Road Users ◽  
Variation Characteristics ◽  
Urban Corridor

The level of service on urban roads quality experienced by the drivers will be varying it is difficult to study the variations due to heterogeneous traffic flow conditions of Indian urban roads. As per TRB, 2010 macroscopic traffic flow parameters are found to be deficient in capturing the quality of service on urban roads experienced by users. Hence the objective of the study is to develop new methodology to evaluate the urban roads in heterogeneous traffic conditions considering the microscopic parameters of traffic flow in a four-lane divided urban corridor. The speed profile of the motorised two-wheelers both in free flow and peak flow were collected from the urban corridor of Bangalore Karnataka, India. Using GPS based mobile application. From the speed profile data, the speed variation characteristics were studied. The various speed indices considered in the study are VN (Velocity noise), CV (Co-efficient of variation), AN (Acceleration noise), and MVG (Mean Velocity Gradient). The CV is considered as the measure of effectiveness, higher the CV more will be the variation of quality experienced by the road users.

scholarly journals Characteristics of traffic flows at roundabouts in the city of Banja Luka before and during COVID-19 crisis

2021 ◽  
Vol 67 (4) ◽  
pp. 31-35
Author(s):  
Nemanja Garunovic ◽  
Vuk Bogdanović ◽  
Slavko Davidović ◽  
Valentina Mirović ◽  
Jelena Mitrović Simić
Keyword(s):  
Traffic Flow ◽  
Flow Characteristics ◽  
Traffic Condition ◽  
State Of Emergency ◽  
Flow Parameters ◽  
Pedestrian Traffic ◽  
The Difference ◽  
Banja Luka ◽  
Restrictive Measures ◽  
The City

COVID-19 pandemic caused many restrictive measures. Most of these measures were in the relationship with the restrictions of mobility which caused some differences in traffic flow demands. In this paper the comparative analysis of traffic flow characteristics at roundabouts in the City of Banja Luka was conducted. The analysis included two different states of traffic condition: the first one, normal condition before COVID-19 crisis, and the second one, during the state of emergency caused by the pandemic. The analysis shows the difference between some of motorized vehicle and pedestrian traffic flow parameters.

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

2019 ◽  
Vol 52 (4) ◽  
pp. 95-108 ◽  
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.

Simulation and evaluation of speed and lane-changing advisory of CAVS at work zones in heterogeneous traffic flow

2020 ◽  
Vol 34 (21) ◽  
pp. 2050201
Author(s):  
Wenjing Wu ◽  
Renchao Sun ◽  
Anning Ni ◽  
Zhikang Liang ◽  
Hongfei Jia
Keyword(s):  
Traffic Flow ◽  
Control Strategy ◽  
Control Strategies ◽  
Heavy Traffic ◽  
Autonomous Vehicle ◽  
Heterogeneous Traffic ◽  
Work Zone ◽  
Lane Changing ◽  
Advantages And Disadvantages ◽  
Car Following Model

Emerging connected autonomous vehicle (CAV) technologies provide an opportunity to the vehicle motion control to improve the traffic performance. This study simulated and evaluated the CAV-based speed and lane-changing (LC) control strategies at the expressway work zone in heterogeneous traffic flow. The control strategies of CAV are optimized by the multi-layer control structure based on model predictive control. The heterogeneous traffic flow composed of human-driven vehicles and CAVs is constructed based on cellular automata by the proposed Expected Distance-based Symmetric Two-lane Cellular Automate (ED-STCA) LC model and CAV car-following model. The six control strategies composed of variable speed limits (VSL), LC and their coordinated control strategies are experimented. The average travel time and throughput are selected to assess the advantages and disadvantages of each strategy under each combination of vehicles’ arrival rates and CAV mixed ratios. The numerical results show that: (i) the effect of the control strategy on the traffic is not obvious under free flow, and the control strategy may worsen the traffic under medium traffic. (ii) Early lane-changing control (ELC) is better than late lane-changing control (LLC) under medium traffic, and LLC is better under heavy traffic. (iii) [Formula: see text] is the best choice under heavy traffic and the mixed rate of CAVs is high. The simulation results obtained in the paper would provide some practical references for transportation agencies to manage the traffic in work zone under networking environment in the future.

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