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Open Access
Article
Publication date: 8 September 2021

Haijian Li, Junjie Zhang, Zihan Zhang and Zhufei Huang

This paper aims to use active fine lane management methods to solve the problem of congestion in a weaving area and provide theoretical and technical support for traffic control…

1044

Abstract

Purpose

This paper aims to use active fine lane management methods to solve the problem of congestion in a weaving area and provide theoretical and technical support for traffic control under the environment of intelligent connected vehicles (ICVs) in the future.

Design/methodology/approach

By analyzing the traffic capacities and traffic behaviors of domestic and foreign weaving areas and combining them with field investigation, the paper proposes the active and fine lane management methods for ICVs to optimal driving behavior in a weaving area. The VISSIM simulation of traffic flow vehicle driving behavior in weaving areas of urban expressways was performed using research data. The influence of lane-changing in advance on the weaving area was evaluated and a conflict avoidance area was established in the weaving area. The active fine lane management methods applied to a weaving area were verified for different scenarios.

Findings

The results of the study indicate that ICVs complete their lane changes before they reach a weaving area, their time in the weaving area does not exceed the specified time and the delay of vehicles that pass through the weaving area decreases.

Originality/value

Based on the vehicle group behavior, this paper conducts a simulation study on the active traffic management control-oriented to ICVs. The research results can optimize the management of lanes, improve the traffic capacity of a weaving area and mitigate traffic congestion on expressways.

Details

Journal of Intelligent and Connected Vehicles, vol. 4 no. 2
Type: Research Article
ISSN: 2399-9802

Keywords

Case study
Publication date: 17 October 2012

Japhet Gabriel Mbura

This case study intends to add knowledge and understanding of supply chain management particularly with respect to international logistics.

Abstract

Subject area

This case study intends to add knowledge and understanding of supply chain management particularly with respect to international logistics.

Study level/applicability

The case study can be used in both undergraduate and postgraduate levels. Students pursuing Master of Science in Logistics, Supply Chain Management and those doing bachelor degrees in the same areas can have a better insight and special interest of the case. Professional boards may also use the case to empirically make students understand this area.

Case overview

The railway sub-sector in East Africa – Tanzania in particular – is an important transport mode but has a declining performance. The market share is estimated at only 4 percent of the freight market. Still knowledge about traffic, particularly for freight, is scant. The main dilemma is whether traffic of the central corridor is more intra- or inter-Tanzania. The case studies techniques appropriate for meaningful traffic forecasting and through a simple regression model it resolves the freight conflicts between Kenya rail and the Central Corridor. It provides students with applied traffic forecasting tools.

Expected learning outcomes

The case focuses on techniques of traffic forecasting, development of traffic scenarios and on issues related to intermodal transport especially between road, rail and ocean. At the end of using this Case students should be able to: explain the methods, techniques and models used in traffic forecasting; understand intermodal linkages in international Logistics; use different approaches to make logistics market assessment; and forecast traffic in all modes using different scenarios.

Supplementary materials

Teaching notes are available for educators only. Please contact your library to gain login details or e-mail support@emeraldinsight.com to request teaching notes.

Article
Publication date: 28 February 2020

Erma Suryani, Rully Agus Hendrawan, Philip Faster Eka Adipraja, Arif Wibisono and Lily Puspa Dewi

This paper aims to address the urban mobility and traffic congestion problem under environmental dynamics to improve mobility and reduce traffic congestion using system dynamics…

1029

Abstract

Purpose

This paper aims to address the urban mobility and traffic congestion problem under environmental dynamics to improve mobility and reduce traffic congestion using system dynamics (SD) simulation and scenarios.

Design/methodology/approach

SD simulation was used to analyze urban mobility and traffic congestion. Data were collected from the Transportation Department of Surabaya City. Several scenarios to improve urban mobility and reduce traffic congestion were developed by modifying the structures and parameters of the model.

Findings

Several factors influence urban mobility, including modal split, trip frequency, delay performance and the ratio of public transport supply and demand. Urban mobility, daily traffic and road capacity are some factors that affect traffic congestion. Scenarios can be designed based on the assumptions of the proposed strategy.

Research limitations/implications

The study was conducted at Surabaya City, East Java, Indonesia, which is the fourth most-congested city in the world.

Practical implications

By implementing several strategies (mass rapid transit and bus rapid transit development and public transport delay reduction), mobility performance is projected to be improved by 70.34-92.96%. With this increased mobility, traffic congestion is projected to decline by 52.5-65.8%.

Originality/value

The novel contributions of this research are: formulating relationships between several variables; modeling dynamic behavior of urban mobility and traffic congestion; and building scenario models to improve mobility and reduce traffic congestion in Surabaya. With the increase in urban mobility and the decrease in average daily traffic, traffic congestion could be reduced by a minimum of 57.6% and a maximum of 69%.

Details

Journal of Modelling in Management, vol. 16 no. 1
Type: Research Article
ISSN: 1746-5664

Keywords

Open Access
Article
Publication date: 1 October 2018

Xunjia Zheng, Bin Huang, Daiheng Ni and Qing Xu

The purpose of this paper is to accurately capture the risks which are caused by each road user in time.

2806

Abstract

Purpose

The purpose of this paper is to accurately capture the risks which are caused by each road user in time.

Design/methodology/approach

The authors proposed a novel risk assessment approach based on the multi-sensor fusion algorithm in the real traffic environment. Firstly, they proposed a novel detection-level fusion approach for multi-object perception in dense traffic environment based on evidence theory. This approach integrated four states of track life into a generic fusion framework to improve the performance of multi-object perception. The information of object type, position and velocity was accurately obtained. Then, they conducted several experiments in real dense traffic environment on highways and urban roads, which enabled them to propose a novel road traffic risk modeling approach based on the dynamic analysis of vehicles in a variety of driving scenarios. By analyzing the generation process of traffic risks between vehicles and the road environment, the equivalent forces of vehicle–vehicle and vehicle–road were presented and theoretically calculated. The prediction steering angle and trajectory were considered in the determination of traffic risk influence area.

Findings

The results of multi-object perception in the experiments showed that the proposed fusion approach achieved low false and missing tracking, and the road traffic risk was described as a field of equivalent force. The results extend the understanding of the traffic risk, which supported that the traffic risk from the front and back of the vehicle can be perceived in advance.

Originality/value

This approach integrated four states of track life into a generic fusion framework to improve the performance of multi-object perception. The information of object type, position and velocity was used to reduce erroneous data association between tracks and detections. Then, the authors conducted several experiments in real dense traffic environment on highways and urban roads, which enabled them to propose a novel road traffic risk modeling approach based on the dynamic analysis of vehicles in a variety of driving scenarios. By analyzing the generation process of traffic risks between vehicles and the road environment, the equivalent forces of vehicle–vehicle and vehicle–road were presented and theoretically calculated.

Details

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

Keywords

Book part
Publication date: 22 July 2004

Leorey Marquez, Nariida Smith, David Kilsby, Mike Taylor and Rocco Zito

A study to investigate the sensitivity of urban freight patterns to various greenhouse abatement policy measures is underway with Metropolitan Sydney being used as the case study…

Abstract

A study to investigate the sensitivity of urban freight patterns to various greenhouse abatement policy measures is underway with Metropolitan Sydney being used as the case study area due to the availability of detailed freight and passenger network level data and models at the New South Wales Transport Data Centre (TDC). The study is designed to build on methodologies under development by TDC to derive freight traffic due to total requirements for freight and relative requirements for categories of goods from actual or forecasted commodity flows and associated information. This paper describes the selection of candidate policy measures for investigation and presents the methodology and processes used in modelling their impacts on urban freight patterns. The discussion will focus on six scenarios which provide policy instruments for application to a 1996 base case. Some results of the modelling of these scenarios will then be presented and issues arising from the study discussed. Special attention will be given to the relative changes in travel characteristics and emissions brought about by these instruments.

Details

Logistics Systems for Sustainable Cities
Type: Book
ISBN: 978-0-08-044260-0

Open Access
Article
Publication date: 1 September 2022

Maytheewat Aramrattana, Jiali Fu and Selpi

This paper aims to explore whether drivers would adapt their behavior when they drive among automated vehicles (AVs) compared to driving among manually driven vehicles…

Abstract

Purpose

This paper aims to explore whether drivers would adapt their behavior when they drive among automated vehicles (AVs) compared to driving among manually driven vehicles (MVs).Understanding behavioral adaptation of drivers when they encounter AVs is crucial for assessing impacts of AVs in mixed-traffic situations. Here, mixed-traffic situations refer to situations where AVs share the roads with existing nonautomated vehicles such as conventional MVs.

Design/methodology/approach

A driving simulator study is designed to explore whether such behavioral adaptations exist. Two different driving scenarios were explored on a three-lane highway: driving on the main highway and merging from an on-ramp. For this study, 18 research participants were recruited.

Findings

Behavioral adaptation can be observed in terms of car-following speed, car-following time gap, number of lane change and overall driving speed. The adaptations are dependent on the driving scenario and whether the surrounding traffic was AVs or MVs. Although significant differences in behavior were found in more than 90% of the research participants, they adapted their behavior differently, and thus, magnitude of the behavioral adaptation remains unclear.

Originality/value

The observed behavioral adaptations in this paper were dependent on the driving scenario rather than the time gap between surrounding vehicles. This finding differs from previous studies, which have shown that drivers tend to adapt their behaviors with respect to the surrounding vehicles. Furthermore, the surrounding vehicles in this study are more “free flow'” compared to previous studies with a fixed formation such as platoons. Nevertheless, long-term observations are required to further support this claim.

Details

Journal of Intelligent and Connected Vehicles, vol. 5 no. 3
Type: Research Article
ISSN: 2399-9802

Keywords

Open Access
Article
Publication date: 18 March 2021

Suyi Mao, Guiming Xiao, Jaeyoung Lee, Ling Wang, Zijin Wang and Helai Huang

This study aims to investigate the safety effects of work zone advisory systems. The traditional system includes a dynamic message sign (DMS), whereas the advanced system includes…

1045

Abstract

Purpose

This study aims to investigate the safety effects of work zone advisory systems. The traditional system includes a dynamic message sign (DMS), whereas the advanced system includes an in-vehicle work zone warning application under the connected vehicle (CV) environment.

Design/methodology/approach

A comparative analysis was conducted based on the microsimulation experiments.

Findings

The results indicate that the CV-based warning system outperforms the DMS. From this study, the optimal distances of placing a DMS varies according to different traffic conditions. Nevertheless, negative influence of excessive distance DMS placed from the work zone would be more obvious when there is heavier traffic volume. Thus, it is recommended that the optimal distance DMS placed from the work zone should be shortened if there is a traffic congestion. It was also revealed that higher market penetration rate of CVs will lead to safer network under good traffic conditions.

Research limitations/implications

Because this study used only microsimulation, the results do not reflect the real-world drivers’ reactions to DMS and CV warning messages. A series of driving simulator experiments need to be conducted to capture the real driving behaviors so as to investigate the unresolved-related issues. Human machine interface needs be used to simulate the process of in-vehicle warning information delivery. The validation of the simulation model was not conducted because of the data limitation.

Practical implications

It suggests for the optimal DMS placement for improving the overall efficiency and safety under the CV environment.

Originality/value

A traffic network evaluation method considering both efficiency and safety is proposed by applying traffic simulation.

Open Access
Article
Publication date: 27 July 2022

Yuchuan Du, Han Wang, Qian Gao, Ning Pan, Cong Zhao and Chenglong Liu

Resilience concepts in integrated urban transport refer to the performance of dealing with external shock and the ability to continue to provide transportation services of all…

1667

Abstract

Purpose

Resilience concepts in integrated urban transport refer to the performance of dealing with external shock and the ability to continue to provide transportation services of all modes. A robust transportation resilience is a goal in pursuing transportation sustainability. Under this specified context, while before the perturbations, robustness refers to the degree of the system’s capability of functioning according to its design specifications on integrated modes and routes, redundancy is the degree of duplication of traffic routes and alternative modes to maintain persistency of service in case of perturbations. While after the perturbations, resourcefulness refers to the capacity to identify operational problems in the system, prioritize interventions and mobilize necessary material/ human resources to recover all the routes and modes, rapidity is the speed of complete recovery of all modes and traffic routes in the urban area. These “4R” are the most critical components of urban integrated resilience.

Design/methodology/approach

The trends of transportation resilience's connotation, metrics and strategies are summarized from the literature. A framework is introduced on both qualitative characteristics and quantitative metrics of transportation resilience. Using both model-based and mode-free methodologies that measure resilience in attributes, topology and system performance provides a benchmark for evaluating the mechanism of resilience changes during the perturbation. Correspondingly, different pre-perturbation and post-perturbation strategies for enhancing resilience under multi-mode scenarios are reviewed and summarized.

Findings

Cyber-physic transportation system (CPS) is a more targeted solution to resilience issues in transportation. A well-designed CPS can be applied to improve transport resilience facing different perturbations. The CPS ensures the independence and integrity of every child element within each functional zone while reacting rapidly.

Originality/value

This paper provides a more comprehensive understanding of transportation resilience in terms of integrated urban transport. The fundamental characteristics and strategies for resilience are summarized and elaborated. As little research has shed light on the resilience concepts in integrated urban transport, the findings from this paper point out the development trend of a resilient transportation system for digital and data-driven management.

Details

Smart and Resilient Transportation, vol. 4 no. 2
Type: Research Article
ISSN: 2632-0487

Keywords

Article
Publication date: 28 January 2022

Tara A. Reis, Jennifer C. Gibbs, Daniel Howard and Emily R. Strohacker

In 2018, the National Human Trafficking hotline received 275 cases of human trafficking in Pennsylvania, a higher than average portion of the 10,949 human trafficking cases…

2387

Abstract

Purpose

In 2018, the National Human Trafficking hotline received 275 cases of human trafficking in Pennsylvania, a higher than average portion of the 10,949 human trafficking cases received for the USA. Whether human trafficking victims receive services or enter the criminal justice system as prostitution offenders depends on how police identify them, as police officers are usually the first to interact with human trafficking victims. Thus, understanding how police identify human trafficking is important. The purpose of the study is to explore Pennsylvania police perceptions of human trafficking.

Design/methodology/approach

Scenarios were presented in a survey to 489 Pennsylvania police officers.

Findings

Police training improved officer identification of human trafficking (vs prostitution) involving older victims. Officers with more tenure were less likely to identify older victims of human trafficking than officers with less tenure. However, older officers were better able to successfully identify older (i.e. age 25 years) victims of human trafficking, but officer age had no effect on identifying younger (i.e. age 15 years) victims of human trafficking. The implications are discussed in the study.

Originality/value

The study contributes to the literature by testing (1) whether training affects police ability to identify human trafficking victims in a scenario, controlling for other factors and (2) whether victim age affects officer identification of human trafficking victims. More officers correctly identified younger victims of human trafficking when force was explicitly stated, but more officers misidentified younger victims when force was not explicitly stated and older victims when force was explicitly stated.

Details

Policing: An International Journal, vol. 45 no. 2
Type: Research Article
ISSN: 1363-951X

Keywords

Article
Publication date: 17 March 2020

Adarsh Kumar, Saurabh Jain and Divakar Yadav

Simulation-based optimization is a decision-making tool for identifying an optimal design of a system. Here, optimal design means a smart system with sensing, computing and…

Abstract

Purpose

Simulation-based optimization is a decision-making tool for identifying an optimal design of a system. Here, optimal design means a smart system with sensing, computing and control capabilities with improved efficiency. As compared to testing the physical prototype, computer-based simulation provides much cheaper, faster and lesser time-and resource-consuming solutions. In this work, a comparative analysis of heuristic simulation optimization methods (genetic algorithms, evolutionary strategies, simulated annealing, tabu search and simplex search) is performed.

Design/methodology/approach

In this work, a comparative analysis of heuristic simulation optimization methods (genertic algorithms, evolutionary strategies, simulated annealing, tabu search and simplex search) is performed. Further, a novel simulation annealing-based heuristic approach is proposed for critical infrastructure.

Findings

A small scale network of 50–100 nodes shows that genetic simulation optimization with multi-criteria and multi-dimensional features performs better as compared to other simulation optimization approaches. Further, a minimum of 3.4 percent and maximum of 16.2 percent improvement is observed in faster route identification for small scale Internet-of-things (IoT) networks with simulation optimization constraints integrated model as compared to the traditional method.

Originality/value

In this work, simulation optimization techniques are applied for identifying optimized Quality of service (QoS) parameters for critical infrastructure which in turn helps in improving the network performance. In order to identify optimized parameters, Tabu search and ant-inspired heuristic optimization techniques are applied over QoS parameters. These optimized values are compared with every monitoring sensor point in the network. This comparative analysis helps in identifying underperforming and outperforming monitoring points. Further, QoS of these points can be improved by identifying their local optimum values which in turn increases the performance of overall network. In continuation, a simulation model of bus transport is taken for analysis. Bus transport system is a critical infrastructure for Dehradun. In this work, feasibility of electric recharging units alongside roads under different traffic conditions is checked using simulation. The simulation study is performed over five bus routes in a small scale IoT network.

Details

Smart and Sustainable Built Environment, vol. 9 no. 4
Type: Research Article
ISSN: 2046-6099

Keywords

1 – 10 of over 8000