Showing papers in "European Journal of Transport and Infrastructure Research in 2019"

Effects of driverless vehicles : Comparing simulations to get a broader picture

Abstract: Driverless vehicles have the potential to significantly affect the transport system, society, and environment. However, there are still many unanswered questions regarding what the development will ...

Stakeholder salience and prioritization for port master planning, a case study of the multi-purpose Port of Isafjordur in Iceland

Abstract: The dynamic and ever-increasing complex nature of a port system involves a variety of stakeholders with a broad spectrum of involvement and objectives. In the port master planning, to fulfill the objectives of the various stakeholders and manage conflicts and controversies, a stakeholder analysis is carried out. However, effective and timely engagement of the key stakeholders in the planning process is not an easy task. This paper presents a framework of stakeholder analysis for the case study of the Multi-Purpose Port of Isafjordur in Iceland to underpin the master planning process. The framework deals with a systematic procedure of identification, grouping and then static mapping of stakeholders by means of the power-interest matrix. Further, the fuzzy logic 3-dimensional decision surface was adopted for dynamic salience mapping of the stakeholders. A survey and face-to-face interviews were conducted as tools to collect input for the stakeholder analysis based on the elements of the port master planning. The elements include competitiveness, land use, environmental implication, safety and security, hinterland connection, economic and social impact, financial performance, and flexibility. This paper reveals that dynamic mapping provides a more accurate stakeholder analysis in the field of port master planning than do other methods. The result of the decision surface shows different saliences of key stakeholders, including legislation and public policy, and internal and external stakeholders in the master planning. Thus, in order to have effective and timely stakeholder inclusion throughout the port planning process, a different strategy of engagement with them should be applied.

Public-private partnerships for infrastructure: Lessons learned from dutch and flemish phd-theses

Abstract: textIn recent years, a considerable number of PhD-dissertations have appeared in the Netherlands and Flanders (Belgium) on Public-Private Partnerships (PPPs) for the provision of public infrastructures such as transport infrastructure and public buildings. These PhD-theses provide valuable insights into how PPPs perform and especially into the conditions that influence their performance. We identified four clusters of relevant conditions: (1) public procurement procedures, (2) contract management, (3) transaction costs, and (4) democratic legitimacy and accountability. By discussing the theses in this article, their lessons learned become available for the international PPP-community. Our analysis of the PhD-theses shows that there are no definite arguments for or against the use of PPPs. The performance of PPP-arrangements depends on agency: on the skills and commitment of parties involved and on the way in which the arrangements are applied. The dissertations show that policymakers have to find ways to balance the need to reduce transaction costs through contract standardization with the need for tailor-made solutions in specific projects. Furthermore, the dissertations show that ‘soft’ contract management aspects, such as the quality of collaborative behavior and process management, are particularly important for the performance of PPPs. Finally, the theses bring to the fore the democratic issues involved in PPPs, showing their mixed results in terms of legitimacy and accountability.

Departure Time Choice and Bottleneck Congestion with Automated Vehicles: Role of On-board Activities

Abstract: The enhanced possibility to perform non-driving activities in automated vehicles (AVs) may not only decrease the disutility of travel, but also change the AV users’ departure time preferences, thereby affecting traffic congestion. Depending on the AV interior, travellers may be able to perform in the vehicle activities that they would otherwise perform at home or at work. These possibilities might make them depart at different times compared to situations, when they are not able to engage in any activities during travel or when the possible activities do not substitute any out-of-vehicle activities. This paper formalises the on-board activity and substitution effects using new scheduling preferences in the morning commute context. The new scheduling preferences are used (1) to analyse the optimal departure times when there is no congestion, and (2) to obtain the equilibrium congestion patterns in a bottleneck setting. If there is no congestion, it is predicted that AV users would choose to depart earlier (later), if the on-board environment is better suited for their home (work) activities. If there is congestion, more AV users departing earlier or later would skew the congestion in the corresponding direction. Given the minimalistic bottleneck setting, it is found that congestion with AVs is more severe than with conventional vehicles. If AVs were specialised to support only home, only work, or both home and work activities, and would do so to a similar extent, then ‘Work AVs’ would increase the congestion the least.

Evaluating the external costs of a modal shift from rail to sea: An application to Sweden’s East coast container movements

Abstract: This study analyzes the comparative level of social and external costs if an existing transport chain is replaced by one that includes a greater use of shipping. The main objective of the paper is ...

Mobility Impacts of Automated Driving and Shared Mobility : Explorative Model and Case Study of the Province of North-Holland

Abstract: This paper presents a model specifically developed to explore the mobility impacts of connected and automated driving and shared mobility. It is an explorative iterative model that uses an elasticity model for destination choice, a multinomial logit model for mode choice and a network fundamental diagram to assess traffic impacts. To the best of the authors’ knowledge, it is the first model that combines a network fundamental diagram with choice models. A second contribution is the inclusion of automated vehicles, automated (shared) taxis, automated shared vans and new parking concepts in the model as well as the way in which they affect mobility choices and traffic conditions. The insights into the direct mobility impacts are the third contribution. The short computation time of the model enables exploration of large numbers of scenarios, sensitivity analyses and assessments of the impacts of interventions. The model was applied in a case study of the Dutch Province of North-Holland, in which the potential impacts of automated and shared vehicles and mitigating interventions were explored. In this case study, four extreme scenarios were explored, in which 100% of the vehicles have SAE-level 3/4 or 5 and people have a low or high willingness to share. The extremes were chosen to get insights into maximum effects. The results show that if automated vehicles and sharing are accepted, it is likely that there will be considerable changes in mobility patterns and traffic performance, with both positive and problematic effects.

Optimization of route choice, speeds and stops in time varying networks for fuel effic ient truck journeys

Abstract: A method is presented for the real-time optimal control of the journey of a truck, travelling between a pair of pick-up/drop-off locations in a time-varying traffic network, in order to reduce fuel consumption. The method, when applied during the journey, encapsulates the choice of route, choice of speeds on the links, and choice of stop locations/durations; when applied pre-trip, it additionally incorporates choice of departure time. The problem is formulated by using a modified form of space-time extended network, in such a way that a shortest path in this network corresponds to an optimal choice of not only route, stops and (when relevant) departure time, but also of speeds. A series of simple illustrative examples are presented to illustrate the formulation. Finally, the method is applied to a realistic-size case study.

Capital structure and firm performance: Evidence from the airport industry

Abstract: The privatisation and liberalisation waves have been increasing the number of private companies in the aviation industry. This, in turn, necessitates new policy analyses on major financial decisions regarding capital structure, corporate governance and investments. Among these major topics, the research about the association between capital structure and financial performance of the aviation companies largely focuses on the airlines. But a comparable analysis for the airport companies is less explored. The goal of this study is to contribute to the literature by analysing how the capital structure of the publicly traded airport companies affects their profitability and market valuation. Using an unbalanced panel data sample of 29 publicly traded airports from 20 countries over the 1989-2017 period, our findings suggest that higher total and long-term leverage tend to decrease return on assets whereas they are positively associated with return on equity.

Multichannel queueing behaviour in urban bicycle traffic

Abstract: The objective of this paper is to propose a method to analyse and describe cyclists’ behaviour at signalized intersections with specific focus on the multichannel (multi-lane) queue phenomenon. As we observed, cyclists form queues without a fixed-lane and FIFO discipline, for which the classical, car-oriented analytical approach becomes insufficient. Cyclists’ multichannel queueing behaviour is common and characterized by substantial degree of variability, especially in case of shorter queues which emerge regularly at cycle crossings. Although cyclist behaviour has been widely studied by transportation research community, their queueing behaviour picture is still incomplete. Namely, there is no method addressed to analyse the full scope of these phenomena and to quantify their impact on the cyclist queue performance. To bridge this gap, we introduce the technique to observe multichannel queues and report relevant observations, which we then complement with a methodological framework to analyse obtained results and provide a complete multichannel queue description. We video-record cyclists as they enqueue to one of multiple channels, form the queue and smoothly merge into a single lane again as the queue discharges. We apply the method to analyse results from a pilot study of 160 cyclists forming 50 queues in the city of Krakow, Poland. The proposed method allows us to analyse and quantify the observed queue performance and its characteristics: the number of channels, their emergence process, channel and queue lengths, discharge process with FIFO violations, starting and discharging times. Findings from pilot study reveal that both queue length and discharge times strongly depend on queue formation process. The contribution of this paper is the method to describe multichannel cyclist queueing behaviour, enriching current picture of bicycle flow and cyclists’ behaviour. Since the method has been developed on relatively short queues (up to 10 cyclists), findings included in this paper primarily refer to such queue sizes. Nonetheless, the method is formulated in a generic way, applicable also for longer bicycle queues. Possible practical implications are new estimates for queue lengths and discharge times - useful for bicycle infrastructure design and traffic engineering purposes.

Effect of dynamic route guidance on urban traffic network under Connected Vehicle environment

Abstract: Although Connected Vehicle technology is developing rapidly, connected vehicles (CV) are going to mix with the traditional vehicles (i.e., non-connected vehicles) for a long time. The effects of deploying CV on urban traffic systems are actually not clear. The main objective of this study is to evaluate the potential effects of route guidance under connected vehicle environment on an urban traffic network in terms of traffic mobility and safety. Microscopic simulation approach is used to conduct CV environment simulation and the rolling horizon approach is used for information updating among the connected vehicles. Meanwhile, driving behavior is modeled through aggressiveness and awareness of drivers. Traffic mobility for the road network was measured by average trip time and average vehicle trip speed. A surrogate measure, i.e., the time-to-collision involved incident rate for one kilometer driven, was used to assess the safety of the road network. Based on a real urban traffic network, the impacts of market penetration levels of connected vehicles and information updating intervals were studied. Simulation results showed that market penetration level of connected vehicles has little impact on the mobility and safety of road network. In addition, according to the simulation conducted in this paper, shorter updating interval is shown to be likely to lead to better mobility, while the safety of road network is likely to decline, under the assumptions embraced in the simulation. By contrast, the simulation also showed that longer updating interval is likely to lead to better safety and decreased mobility.

Case study on effects of the mandatory validation on bus commercial speed

Abstract: The paper aims to define the new operational requirements and procedures to allow the Gruppo Torinese Trasporti (Torino public transport company) to implement mandatory validation without negative impacts on both the company and the users. To this end, a four-step methodology has been put forward: a) choice of the reference route; b) sampling plan and data collection; c) data analysis design and model specification and d) definition and analysis of future scenarios. Attained results show an increase of commercial speed from 1.5% to 14.5%, and an increase of the proportion of total dwell time on total trip time from 1 to 13 points. The most unfavourable situation for the company would be banning people from boarding the bus/tram through any door (the case today). Indeed, it would require an increase of trips in the morning peak hour in order to maintain the same time interval at bus stops. However, the impact on passengers’ travel time is non negligible since total vehicle trip time shows a rise of up to 10 minutes during weekends shifts (from 62 minutes in the current situation to 72 minutes for the worst case scenario). Thus, the present system limits the outcomes negatively for the users in terms of waiting time. However, a change could lead to such positive consequences as fuller passenger cooperation to validate tickets/passes and a more ordered boarding, thus reducing fraud and improving the image of the company.

Modelling risky driving behaviour: the role of latent variables in overtaking decision on two-lane highways

Abstract: This paper aims to demonstrate that advanced technique of modelling may provide insights and improve our understanding of driver behavior in risky decision-making situations. The paper introduces a Hybrid choice model in order to explain the overtaking decision on two-lane highways, which is well known as a risky decision in the safety literature. This model integrates a latent variable model and an overtaking choice model by combining their measurement and structural equations. Specifically, the paper investigates the role of four personality latent variables: Thrill and Adventure Seeking, Boredom Susceptibility, Geographic Ability, and Driving Anger. Respondents to a web-based survey ranked their likelihood to overtake on two-lane highways; two scenarios were captured via short videos: the first presenting a straight section of a road with good visibility, and the second approaching a curve with reduced visibility. Several indicators were collected via self-reported questionnaire. Results indicate that, two out of the four personality latent variables investigated, Thrill and Adventure Seeking and Geographic Ability provide significant explanation for overtaking decision. Both of them are positively correlated with higher risky overtaking behavior. The Hybrid model, by considering latent variables alongside observable variables and attributes of the decision, enhances the comprehension of overtaking behaviour, and therefore may be deployed for explaining other decisions related to risky driving behaviour.