Future Transp., Volume 2, Issue 1 (March 2022) – 16 articles

Having been widely acknowledged as enabling access to education, employment, leisure and social activities, transport choices are also the cause of many challenges cities face. Recognising that change is needed, planners and policymakers are considering alternative methods of planning and delivering transport. Mobility as a Service (or MaaS) is one such idea that has gained traction with academics and professionals alike. Hailed as the answer to integrating complex transport systems, MaaS has yet to be implemented at scale in urban transport systems due in part to the lack of an agreed conceptual definition, the top-down approach to implementing what is meant to be a more personalised method of accessing transport, and the lack of local promoters (in comparison to global corporations and lobbyists). This article reflects on the current barriers to defining MaaS, considers how a novel public engagement approach could be used to create local definitions that support citizen engagement, and suggests a route forward for future research. Full article

Despite fast technological advances, the worldwide adoption of electric vehicles (EVs) is still hampered mainly by charging time, efficiency, and lifespan. Lithium-ion batteries have become the primary source for EVs because of their high energy density and long lifetime. Currently, several methods intend to determine the health of lithium-ion batteries fast-charging protocols. Filling a gap in the literature, a clear classification of charging protocols is presented and investigated here. This paper categorizes fast-charging protocols into the power management protocol, which depends on a controllable current, voltage, and cell temperature, and the material aspects charging protocol, which is based on material physical modification and chemical structures of the lithium-ion battery. In addition, each of the charging protocols is further subdivided into more detailed methodologies and aspects. A full evaluation and comparison of the latest studies is proposed according to the underlying parameterization effort, the battery cell used, efficiency, cycle life, charging time, and increase in surface temperature of the battery. The pros and cons of each protocol are scrutinized to reveal possible research tracks concerning EV fast-charging protocols. Full article

White topping is a popular road rehabilitation technique that uses Portland cement concrete overlay on top of any existing bituminous pavement. However, this often results in additional cost and carbon emission escalations which complicates market useability of the product. The current study aims at comparing carbon emission and manufacturing cost of concrete topping mixes with three different fibre types. The study optimises the benefits and promotes the use of effective materials in sustainable road rehabilitation. Samples with polyolefin-twisted (F2) fibres indicated least carbon emission escalation while the sample with polypropylene (F3) exhibited least cost escalation with 0.75% and 7.17% from the control sample respectively. A multi-objective genetic optimisation study was conducted to identify the mix designs with least carbon emission and production cost escalations. Sensitivity analysis illustrated that transport distance is a critical contributing factor for production cost while carbon emission is highly sensitive to emission factors for transport and cement production. These results indicate the importance of considering locally available materials and clean energy for production processes. Future research can be focused on exploring the long-term environmental and economic benefits including the durability characteristics to benchmark the sustainable benefits of using waste fibre materials in the mix. Full article

COVID-19 pandemic impacted the behaviour of travellers. While worldwide, overall emissions decreased during the lockdown, shared mobility options may be perceived as less safe in a post-pandemic reality, leading to increased emissions due to expanded individual transportation. In particular, intercity trips entail numerous environmental impacts, such as emissions. The main objective of this paper is to assess how intercity corridors’ emissions vary when travel behaviour of the population changes following a pandemic. Based on a macroscopic modelling framework, the methodology consisted of three main phases: data collection, traffic modelling and emission modelling. Different scenarios related to the impact of the pandemic were developed, and their impacts were analysed using several key performance indicators related to CO₂ NO_x emissions and travel time. Findings suggest that reducing the average number of occupants per vehicle reduces emissions, which do not increase linearly with the number of vehicles. Compared with the baseline scenario (occupancy rate of 1.30), the most extreme scenario (occupancy rate of 1.00) may result in an increase in both CO₂ and NO_x emissions by approximately 30%. These results highlight the importance of making public transport and carpooling not only safe but also safe as perceived by users. Full article

Wyoming has one of the highest fatality rates, and a significantly lower rate of seatbelt use in the United States. Thus, this study was conducted with the objective to investigate contributory factors to the choice of drivers’ seatbelt use. Various environmental factors and drivers’ characteristics were considered as it is expected that they account for unseen factors that impact drivers’ choice of buckling up. Although the mixed model has been used extensively for studying the impacts of seatbelt use on the severity of crashes, not many studies have been conducted regarding factors contributing to the choice of seatbelt use itself. In this study, the standard logit model is extended to the mixed model to account for heterogeneity across drivers’ observations. In addition, the standard mixed model was extended to incorporate the random parameters’ heterogeneity in taste based on the means of other observed variables. The results highlighted that moving from the standard logit model to the mixed model, considering heterogeneity in tastes, results in a gain in the model fit, and also an adjustment for the model’s parameters’ estimates. The findings indicated that some of factors impacting the choice of wearing seatbelt include gender, road classification, weather condition, vehicle types, time of driving, vehicle registration and day of the week. Those factors are mainly related to unobserved factors impacting the drivers’ behaviors. For instance, drivers with particular characteristics are expected to own particular vehicle types or drive their vehicles under a particular weather condition. Full article

The way in which people choose to travel has changed throughout history and adaptations have taken place in order to provide the most convenient, efficient and cost-effective method(s) of transport possible. This research explores two trends—technological and socio-economic change—by discussing the effects of their application in the renewed drive to promote car clubs in Greater London through the introduction of new technologies and innovative ways in which a car can be used and hired, thus helping to generate new insights for car sharing. A mixed methods approach was used, combining secondary data analysis obtained from a car club member survey of 5898 people with in-depth, semi-structured interviews. Our findings show that there is an opportunity to utilise car clubs as a tool for facilitating a step change away from private vehicle ownership in the city. In addition, the results suggest that car club operators are seeking to deliver a mode of transport that is able to compete with private car ownership. In terms of policy implications, such findings would suggest that compromise is necessary, and an operator/authority partnership would offer the most effective way of delivering car clubs in a manner that benefits all Londoners. Full article

Transport sector models help provide strategic information for the future development of the transportation sector. Such long-term scenarios are typically challenged by uncertainties. Moreover, certain trends, such as the transition to zero-emission transportation systems and modal shifts, as well as connected, shared and autonomous vehicles, are already apparent today. Therefore, this paper investigates the impact of these trends on greenhouse gas emissions, as well as their implementation in transport sector modeling thus far. The investigations are structured into the four main parts of transport sector greenhouse gas emission calculation: activity, modal share, energy intensity and fuel carbon intensity. Our analysis of the related effects reveals their importance to the transportation sector of the future. Current models and scenarios widely consider trends such as the modal shift and electrification. However, other trends such as the sharing economy and automated driving are not commonly regarded in the context of transport sector modeling. The coupling of the different types of models and collaboration among researchers from the different fields is recommended for filling this gap. Full article

Nowadays, authorities of large cities in the world implement bus rapid transit (BRT) services to alleviate traffic problems caused by the significant development of urban areas. Therefore, a controller is required to control and dispatche buses in such BRT systems.. However, controllers are facing new challenges due to the inherent uncertainties of passenger parameters such as arrival times, demands, alighting fraction as well as running time of vehicles between stops. Such uncertainties may significantly increase the operational cost and the inefficiencies of BRT services. In this paper, we focus on the controller’s perspective and propose a stochastic mixed-integer nonlinear programming (MINLP) model for BRT scheduling to find the optimal departure time of buses under uncertainty. The objective function of the model consists of passenger waiting and traveling time and aims to minimize total time related to passengers at any stop. From the modeling perspective, we propose a new method to generate scenarios for the proposed stochastic MINLP model. Furthermore, from the computational point of view, we implement an outer approximation algorithm to solve the proposed stochastic MINLP model and demonstrate the merits of the proposed solution method in the numerical results. This paper accurately reflect the complexity of BRT scheduling problem and is the first study, to the best of our knowledge, that presents and solves a mixed-integer nonlinear programming model for BRT scheduling. Full article

Micromobility is an increasingly attractive option, particularly over short distances. Walking, biking, and other modes of transport, such as e-scooters, are gaining popularity. Furthermore, a trend is emerging to introduce appealing items onto the market that incorporate new/more sustainable materials to improve wellbeing. Significant research questions concern the understanding of emerging research needs and the environmental, social, and economic effects of sustainability in the micromobility transport system, specifically because of developing and implementing new products, boosting the safety and comfort of ergonomic personal mobility devices (PMDs), and assuring security and privacy while digitalization arises. Such research topics can raise policymakers’ and the public’s awareness while providing impactful information for decision-makers. This paper provides a literature review of the most recent research on micromobility-related topics. It uses scientific databases, a keywords list, and defined inclusion criteria to select data, analyze content, and perform a bibliometric analysis. The findings highlight the significance of using Life Cycle Assessment (LCA) tools together with other methodologies to aid in the evaluation of urban complexity. Finally, using a life cycle thinking (LCT) approach, we propose a framework for comprehensively integrating identified research needs. Full article

Transportation is one of the main enablers of development. It connects communities, allows the trade of goods among territories, and provides equitable access to public services. However, it is also one of the main causes of climate change, impacting directly and indirectly on human health. This raises the need for transportation infrastructure to be more sustainable so that it can enable more sustainable development. This paper investigates how sustainability in the transport sector can be conceptualized, assessed, and implemented. Definitions are proposed, indicators identified, existing methods reviewed, and three case studies presented. The Sustainable Asset Valuation (SAVi) method and resulting integrated simulation models are used to assess the multidimensional outcomes of conventional and sustainable transport investments. The cases of roads, public bicycle-sharing and bus rapid transport systems are discussed. These investments are assessed using an integrated cost–benefit analysis that goes beyond traditional assessments, considering the benefits and avoided costs of the externalities of a project in the social, environmental, and economic dimensions. The use of the method led to the conclusion that including externalities in a cost–benefit analysis is meaningful and can be relevant for assessing the economic viability of transport infrastructure projects. Full article

This article presents a literature review of Transition Experiments applied to the Sustainable Urban Mobility context from a critical and operative point of view. The moment of transformation that we are living through determines concerns about the decarbonization and compliance with the 2050 Targets and imposes a paradigm shift towards sustainable urban mobility. In this regard, the necessary physical change will have to be accompanied by a socio–cultural transition, of which the challenge implies the construction of a collective ideal, shared by the population and the main stakeholders, leading to the opening of new political spaces and a change, also in terms of governance. Full article

Crowdsourced deliveries or crowdshipping is identified in recent literature as an emerging urban freight transport solution, aiming at reducing delivery costs, congestion, and environmental impacts. By leveraging the pervasive use of mobile technology, crowdshipping is an emerging solution of the sharing economy in the transport domain, as parcels are delivered by commuters rather than corporations. The objective of this research is to evaluate the impacts of crowdshipping through alternative scenarios that consider various levels of demand and adoption by public transport users who act as crowdshippers, based on a case study example in the city of Volos, Greece. This is achieved through the establishment of a tailored evaluation framework and a city-scale urban freight traffic microsimulation model. Results show that crowdshipping has the potential to mitigate last-mile delivery impacts and effectively contribute to improving the system’s performance. Full article

This paper presents an assessment of enabling technologies in intermodal freight transport. It first identifies the technologies used in intermodal freight transport globally using a systematic literature review. Then, it characterizes intermodal freight transport in the context of low-income countries to assess the potential application of digitalization and automation for the countries. Countries with a per capita gross national income (GNI) lower than $1025 are categorized as low-income countries. To achieve the objectives, a review was undertaken of 147 published articles from Scopus, Web of Science, and Transport Research International Documentation (TRID). Furthermore, distinctions of intermodal transport in low-income countries were also characterized using gray literature. A number of enabling technologies applied at components of intermodal transport were identified. The results demonstrated that several enabling technologies such as wireless communication technology, sensors, positioning technology, and web-based platforms are highly utilized in intermodal freight transport globally. In contrast, electronic data interchange (EDI), wireless communication technologies, and web-based platforms also have potential applications in low-income countries, and their adoption should be studied further. Full article

Road traffic crashes are a major safety problem, with one of the leading factors in crashes being human error. Automated and connected vehicles (CAVs) that are equipped with Advanced Driver Assistance Systems (ADAS) are expected to reduce human error. In this paper, the Simulation of Urban MObility (SUMO) traffic simulator is used to investigate how CAVs impact road safety. In order to define the longitudinal behavior of Human Drive Vehicles (HDVs) and CAVs, car-following models, including the Krauss, the Intelligent Driver Model (IDM), and Cooperative Adaptive Cruise Control (CACC) car-following models were used to simulate CAVs. Surrogate safety measures were utilized to analyze CAVs’ safety impact using time-to-collision. Two case studies were evaluated: a signalized grid network that included nine intersections, and a second network consisting of an unsignalized intersection. The results demonstrate that CAVs could potentially reduce the number of conflicts based on each of the car following model simulations and the two case studies. A secondary finding of the research identified additional safety benefits of vehicles equipped with collision avoidance control, through the reduction in rear-end conflicts observed for the CACC car-following model. Full article

In recent decades cities have applied a number of policy measures aimed at reducing car use and increasing public transportation (PT) patronage. Persuasive strategies to change mobility behavior present notable limitations in economic and logistical terms and have only minor impacts. The smartphone has emerged as a promising tool to overcome these challenges, as it can host persuasion strategies through mobility apps. Simultaneously, Mobility-as-a-Service (MaaS) schemes could open up new possibilities for addressing both sustainability goals and the needs of urban travelers. This paper carries out a literature review to identify the key elements of mobility apps that foster more sustainable travelers’ choices. The findings show that some persuasive strategies such as eco-feedback, rewards or social challenges are effective because they are well received by users. From the users’ point of view, the perceived barriers (e.g., usability, privacy) relate negatively to app adoption, and it is considered useful to include functional needs such as real-time information (e.g., to avoid congestion), cost savings (e.g., customized multimodal packages), comfort (e.g., crowding on public transport) or health (e.g., calories burned). We have found that a proper design of multimodal travel packages based on (i) financial incentives and (ii) environmental awareness, could help increase public transport patronage and reduce private car use. Full article