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Article
Publication date: 30 July 2019

Zhizhou Wu, Yiming Zhang, Guishan Tan and Jia Hu

Traffic density is one of the most important parameters to consider in the traffic operation field. Owing to limited data sources, traditional methods cannot extract…

Abstract

Purpose

Traffic density is one of the most important parameters to consider in the traffic operation field. Owing to limited data sources, traditional methods cannot extract traffic density directly. In the vehicular ad hoc network (VANET) environment, the vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) interaction technologies create better conditions for collecting the whole time-space and refined traffic data, which provides a new approach to solving this problem.

Design/methodology/approach

On that basis, a real-time traffic density extraction method has been proposed, including lane density, segment density and network density. Meanwhile, using SUMO and OMNet++ as traffic simulator and network simulator, respectively, the Veins framework as middleware and the two-way coupling VANET simulation platform was constructed.

Findings

Based on the simulation platform, a simulated intersection in Shanghai was developed to investigate the adaptability of the model.

Originality/value

Most research studies use separate simulation methods, importing trace data obtained by using from the simulation software to the communication simulation software. In this paper, the tight coupling simulation method is applied. Using real-time data and history data, the research focuses on the establishment and validation of the traffic density extraction model.

Details

Journal of Intelligent and Connected Vehicles, vol. 2 no. 1
Type: Research Article
ISSN: 2399-9802

Keywords

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Book part
Publication date: 12 September 1997

Carlos F. Daganzo

Abstract

Details

Fundamentals of Transportation and Traffic Operations
Type: Book
ISBN: 978-0-08-042785-0

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Article
Publication date: 9 April 2020

Xinyue Qi, Rongjun Cheng and Hongxia Ge

This study aims to consider the influence of density difference integral and relative flow difference on traffic flow, a novel two-lane lattice hydrodynamic model is…

Abstract

Purpose

This study aims to consider the influence of density difference integral and relative flow difference on traffic flow, a novel two-lane lattice hydrodynamic model is proposed. The stability criterion for the new model is obtained through the linear analysis method.

Design/methodology/approach

The modified Korteweg de Vries (KdV) (mKdV) equation is derived to describe the characteristic of traffic jams near the critical point. Numerical simulations are carried out to explore how density difference integral and relative flow difference influence traffic stability. Numerical and analytical results demonstrate that traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

Findings

The traffic congestions can be effectively relieved considering density difference integral and relative flow difference.

Originality/value

Novel two-lane lattice hydrodynamic model is presented considering density difference integral and relative flow difference. Applying the linear stability theory, the new model’s linear stability is obtained. Through nonlinear analysis, the mKdV equation is derived. Numerical results demonstrate that the traffic flow stability can be efficiently improved by the effect of density difference integral and relative flow difference.

Details

Engineering Computations, vol. 37 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 27 April 2012

Carlos Gershenson and David A. Rosenblueth

The purpose of this paper is to compare qualitatively two methods for coordinating traffic lights: a static optimization “green wave” method and an adaptive self‐organizing method.

Abstract

Purpose

The purpose of this paper is to compare qualitatively two methods for coordinating traffic lights: a static optimization “green wave” method and an adaptive self‐organizing method.

Design/methodology/approach

Statistical results were obtained from implementing a recently proposed model of city traffic based on elementary cellular automata in a computer simulation.

Findings

The self‐organizing method delivers considerable improvements over the green‐wave method. Seven dynamical regimes and six phase transitions are identified and analyzed for the self‐organizing method.

Practical implications

The paper shows that traffic light coordination can be improved in cities by using self‐organizing methods.

Social implications

This improvement can have a noticeable effect on the quality of life of citizens.

Originality/value

Understanding how self‐organization obtains adaptive solutions for complex problems can contribute to building more efficient systems.

Details

Kybernetes, vol. 41 no. 3/4
Type: Research Article
ISSN: 0368-492X

Keywords

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Book part
Publication date: 14 September 2007

Robin Lindsey and Erik Verhoef

Abstract

Details

Handbook of Transport Modelling
Type: Book
ISBN: 978-0-08-045376-7

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Article
Publication date: 1 June 2020

Ting Wang, Rongjun Cheng and Hongxia Ge

The purpose of this paper is to explore the impact of the mixed traffic flow, self-stabilization effect and the lane changing behavior on traffic flow stability.

Abstract

Purpose

The purpose of this paper is to explore the impact of the mixed traffic flow, self-stabilization effect and the lane changing behavior on traffic flow stability.

Design/methodology/approach

An extended two-lane lattice hydrodynamic model considering mixed traffic flow and self-stabilization effect is proposed in this paper. Through linear analysis, the stability conditions of the extended model are derived. Then, the nonlinear analysis of the model is carried out by using the perturbation theory, the modified Kortweg–de Vries equation of the density of the blocking area is derived and the kink–antikink solution about the density is obtained. Furthermore, the results of theoretical analysis are verified by numerical simulation.

Findings

The results of numerical simulation show that the increase of the proportion of vehicles with larger maximum speed or larger safe headway in the mix flow are not conducive to the stability of traffic flow, while the self-stabilization effect and lane changing behavior is positive to the alleviation of traffic congestion.

Research limitations/implications

This paper does not take into account the factors such as curve and slope in the actual road environment, which will have more or less influence on the stability of traffic flow, so there is still a certain gap with the real traffic environment.

Originality/value

The existing two-lane lattice hydrodynamic models are rarely discussed in the case of mixed traffic flow. The improved model proposed in this paper can better reflect the actual traffic, which can also provide a theoretical reference for the actual traffic governance.

Details

Engineering Computations, vol. 38 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 1 July 2014

Andy H.F. Chow and Ying Li

This paper aims to present a linear mathematical framework for modeling and optimizing road transport infrastructure. The framework assesses and optimizes performance of…

Abstract

Purpose

This paper aims to present a linear mathematical framework for modeling and optimizing road transport infrastructure. The framework assesses and optimizes performance of existing transport facility rather than relying on building new roads for the ever-increasing travel demand.

Design/methodology/approach

The mathematical framework is built upon a traffic model called Cell Transmission Model (CTM). CTM describes the relationship and evolution of traffic flow and concentration over space and time. The model is parsimonious and accurate in predicting traffic dynamics. More importantly, the traffic flow model is piecewise linear with which the corresponding transport facility optimization problem can be formulated as a Linear Programming (LP) problem and solved by established solution algorithm for global optimality.

Findings

We select a section on England Motorway M25 as a case study. With traffic data, we first calibrate the CTM, and we are able to produce traffic estimation with a reasonable error rate of 12 per cent. The corresponding LP then seeks an optimal ramp metering strategy that minimizes the delay on the motorway. It is shown that an optimal and practical strategy can be derived which reduces the motorway delay by 10 per cent without significantly hurting the surrounding connectors.

Originality/value

Instead of the tedious microscopic models used by many traditional tools, the underlying CTM is parsimonious and reliable. The tools developed herein are based upon plausible traffic theory and will be accessible for a wide range of users. The LP formulation can be easily implemented and solved for optimal and practical control strategies for real-world transport networks by using existing computer software (CPLEX) within reasonable computational time. The present work will certainly contribute to the sustainable development of transport facility.

Details

Journal of Facilities Management, vol. 12 no. 3
Type: Research Article
ISSN: 1472-5967

Keywords

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Article
Publication date: 17 August 2012

Jacques Penders and Lyuba Alboul

This paper aims to discuss traffic patterns generated by swarms of robots while commuting to and from a base station.

Abstract

Purpose

This paper aims to discuss traffic patterns generated by swarms of robots while commuting to and from a base station.

Design/methodology/approach

The paper adopts a mathematical evaluation and robot swarm simulation. The swarm approach is bottom‐up: designing individual agents the authors are looking for emerging group behaviour patterns. Examples of group behaviour patterns are human‐driven motorized traffic which is rigidly structured in two lanes, while army ants develop a three‐lane pattern in their traffic. The authors copy army ant characteristics onto their robots and investigate whether the three lane traffic pattern may emerge. They follow a three‐step approach. The authors first investigate the mathematics and geometry of cases occurring when applying the artificial potential field method to three “perfect” robots. Any traffic pattern (two, three or more lanes) appears to be possible. Next, they use the mathematical cases to study the impact of limited visibility by defining models of sensor designs. In the final step the authors implement ant inspired sensor models and a trail following mechanism on the robots in the swarm and explore which traffic patterns do emerge in open space as well as in bounded roads.

Findings

The study finds that traffic lanes emerge in the swarm traffic; however the number of lanes is dependent on the initial situation and environmental conditions. Intrinsically the applied robot models do not determine a specific number of traffic lanes.

Originality/value

The paper presents a method for studying and simulating robot swarms.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 5 no. 3
Type: Research Article
ISSN: 1756-378X

Keywords

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Book part
Publication date: 20 June 2017

David Shinar

Abstract

Details

Traffic Safety and Human Behavior
Type: Book
ISBN: 978-1-78635-222-4

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Book part
Publication date: 12 November 2018

Luis Chicaiza-Vaca Jorge and Andrés Hidalgo-Carvajal David

The fast growth of urban areas in major cities worldwide is undoubtedly one of the biggest concerns for city officials. In Latin America, data show that currently 81% of…

Abstract

The fast growth of urban areas in major cities worldwide is undoubtedly one of the biggest concerns for city officials. In Latin America, data show that currently 81% of its inhabitants live in urban areas, and calculations forecast an increase in this percentage. In this context, urban logistics would become increasingly important in the overall performance of the region and its cities. The main objective of this study was to develop a set of key performance indicators (KPIs) to complement the square kilometer (km2) methodology developed by MIT, applying it in a highly intensive HORECA (hotels, restaurant, coffee shops) area known as “Zona T (The T Zone)” in Bogotá, Colombia, as this is a critical area where distribution needs to be performed at its best. Data such as shop inventory (stores, restaurants, drugstores, etc.), vehicle counting (cars, buses, motorbikes, trucks, etc.), product deliveries (by type: perishables, groceries, cleaning supplies, etc.), and traffic disruptions were collected through observation. Based on literature review and results of the study, 13 KPIs are proposed in three categories: operational (average distance and store coverage, service time & service rate, store density, delivery points, easiness for delivery and vehicle delivery factor), energy and environmental (fuel consumption and emissions), and traffic (traffic density, speed and traffic per lane). The main results show a 62-m average distance from truck to store, service time of 18:36 min, 1.019 gal and 9.1 kg CO2e of fuel consumption and emission, respectively, traffic density of 421 vehicles/h, and other results described throughout the document.

Details

Supply Chain Management and Logistics in Latin America
Type: Book
ISBN: 978-1-78756-804-4

Keywords

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