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End-to-end drone route planning in flexible airspace design

Drone traffic, consisting of anything from small quadcopters for video and photography to large eVTOL transporting people, is expected to grow rapidly as soon as the challenges currently barring urban flights can be solved. One of the main challenges is how to automate authorization while both keeping full control over where and how drones fly over specific areas, and at the same time allowing the operators the freedom they require to successfully provide their services. While restrictions are necessary, being overly restrictive on plans has a negative impact on capacity, safety and efficiency. In this article we propose the combination of no-fly zones and flight grids into design elements for airspace design, to be used only where and when necessary. City planners can use these design elements to make both strategic decisions and real-time updates, and thereby set the rules for an automated system for planning and authorization. We describe the design elements, how to automatically find the optimal end-to-end route between or through these elements, a set of modifications or extension to improve flexibility even more, and demonstrate the efficacy of the approach through example airspace design patterns and by showing the resulting traffic in a drone traffic simulator.

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Sensitivity analysis of activity scheduling parameters with a parameter optimization framework

Transportation-related activity scheduling is becoming more complex due to the growing number of potential locations and extensive opportunities to visit various places. Throughout the years, in the field of transportation several attempts were made to optimize travelers’ activity chains with different parameters to set, but there is a lack of comprehensive solutions. In this research, the activity chain optimization algorithm is applied, which requires high computational efforts. To provide an adequate calibration of the parameters, a sensitivity analysis is conducted. The aim of the analysis is to reveal how changes in the attribute values modify the final outcomes. The relevant parameters, activity chains, transport modes, optimization algorithms, and fitness functions, are identified and considered. For each parameter, an investigation is conducted to reveal its behavior throughout the runs. For example, changes in the population size and crossover function lead to more reliable results, while alteration in the number of generations and the mutation function have no effects on the outcomes. The analysis presents a peculiar behavior of the parameters related to the activity chains. The results can be useful for transportation planners and service providers in the adaptation of the existing network and transportation services to the travelers’ mobility patterns.

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Towards development of a roadway flood severity index

Flooding is among the costliest and deadliest weather disasters. Moreover, different types of flooding have significant impacts on the transportation network and infrastructure including flash, riverine, urban, coastal, and storm surge. The variety of flooding scenarios makes it challenging to quantify the impacts of flooding on transportation across spatial scales; however, such metrics would be beneficial both prior to and after the event. Pre-flood metrics can promote enhanced impact-based decision-support guidance and hazard communication, while post-flood metrics may include larger regional disruptions located away from the most inundated areas and their associated secondary societal impacts. This study developed a retrospective Roadway Flood-Severity Index (RFSI) from 1982 to 2020 capable of integrating geo-located hydrometeorological data and transportation mobility information across localized and multi-state, sub-national regions to (1) categorize larger-scale, flood-related transportation disruptions, (2) understand the origins of those disruptions, and (3) identify severity risk levels of individual road segments and broader regions of transportation disruption during flood events. The fundamental question is, as flooding events unfold, can past hydrometeorological inundation information be coupled with transportation system network and mobility data to identify the most vulnerable roadway segments and regions? The overall mobility impacts of flooding on transportation were highly variable and relatively uncommon throughout the study period. Given this variability in other mobility data (e.g., vehicle speeds), hydrometeorological parameters were used exclusively as model inputs and crowdsourced Waze flood reports were used as the target response variable. A logistic regression based RFSI was found to best align with the dataset providing a “no flood” or “flood” classification. Eventually, this retrospective analysis will be extended to provide predictive capability as well. The RFSI is intended to provide transportation agencies with a quantitative metric to classify, categorize, and communicate the potential impacts of flood events throughout the transportation network.

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Modeling with a municipality: Exploring robust policies to foster climate-neutral mobility

Many European cities are investigating how to transition to climate-neutral transport systems. Due to the transport system’s complexity and uncertainty about the future, identifying drivers and choosing effective policies to make the city more sustainable is challenging. Additionally, the chosen policies need to be supported by relevant actors. This study aims to support the municipality of The Hague in generating robust policies supported by and within the municipality. We build on participatory modeling and decision-making under deep uncertainty to create a novel approach to address this goal. In two workshops, the participants formulated goals and objectives, created Causal Loop diagrams, and identified potential interventions. Using a set of possible futures, the interventions were then stress-tested to evaluate their robustness. By explicitly linking, for the first time, participatory modeling and decision-making under deep uncertainty approaches, the participants could understand the system better and deal with uncertainty. Participants gained insight into systemic complexity and methods to deal with it, the inter-relatedness of interventions and their effects, and a shared understanding of the problem and its scope. This study demonstrates the potential of a novel approach to generate supported robust interventions to achieve the goal of a climate-neutral transport system.

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Lacking knowledge or lacking support? An informed choice study of support for mileage fees as an alternative to gas taxes

Governing bodies are continuing to research, conduct pilot programs, and adopt policy for mileage fees as alternatives to the gas tax, yet public support remains critically low. Lack of support generally stems from assumptions that mileage fees will cost more, be inequitable for rural and low-income households, and will impede privacy through invasive mileage collection. In this study, we assess the extent to which these perceptions of mileage fees, which ultimately shape policy opinion formation, are related to low levels of information or lacking information. We also evaluate the unique aspects of policy opinion formation, including engagement with both individual and aggregate ideologies and material self-interests. Our survey instrument encourages issue engagement through iterative voting and educational experiences, through which we see information has a statistically significant effect on policy opinions and changes what we think we know about public support for mileage fees. Across the educational experiences, which include policy-relevant information provided through videos and tailored annual cost calculations for the policy alternatives, 24% of respondents changed their opinion by the end of the study, and 44% changed their opinion at least once during the study. We conclude with suggestions for public opinion polling around controversial policies that apply to both researchers and practitioners looking to engage with their constituents.

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Identifying the contribution of communication and trust in aviation maintenance occurrences: A content analysis methodology

As communication and trust are both linked with safety, this paper aims to investigate their contribution to aviation maintenance incidents and accidents. For this purpose, the content analysis method is used to investigate whether trust and communication factors were present in aviation maintenance occurrences. Content analysis is used as a qualitative and quantitative tool. For the data analysis, apart from direct investigation for keywords throughout the material for analysis (aviation accident/incident reports with maintenance involvement), a survey tool was also employed. The items of this survey tool (Communication and Trust Question Set) were used to filter the reports’ text to indirectly identify the two factors under examination (communication and trust). As a qualitative tool, the content analysis yielded results via mapping and narrative techniques. As a quantitative tool, results were obtained and reported with the help of descriptive statistics (counts, frequencies). The results indicated that elements of trust and communication are indirectly detectable in aviation maintenance occurrences. Both ineffective communication and lack of trust were identified as a key accident/incident causal condition. Interpersonal trust is recommended to be included in the implementation requirements of any communication system. The limitations associated with the difference in the structure and consistency of the examined material are also discussed.

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Assessing the impact of driver compliance on traffic flow and safety in work zones amid varied mixed autonomy scenarios

The safety of work zones is a critical issue for drivers, transportation agencies, and governing authorities. In particular, the vehicles that perform lane changes in the proximity of the work zones involving lane closure, pose a significant threat to the safety of the public and the work zone workers, as they need to complete a forced merging. Yet, there is no comprehensive simulation framework to examine the work zone traffic safety under different compliance distributions of the drivers to the warning delivery for the work zone in a mix-autonomy operation of autonomous and human-driven vehicles. To fill this void, we present an integrated microsimulation framework to assess the correlation between the number of vehicles that perform late merge at the taper (LMT) and traffic mobility and safety under different empirical compliance distributions of the drivers to the warning delivery for the downstream work zone.We employ different work zone configurations to illustrate the relationship between late merges at the taper and performance indicators for traffic mobility and safety of the work zone under a variety of work zone configurations. Simulation results show that compliance distribution significantly impacts the number of late merges at the taper (LMTs) and thereby traffic safety and efficiency. Our findings demonstrate that when human-driven vehicles exhibit high compliance behavior to the merging warning signs, it can offset the impact of the lower percentage of market penetration rate (MPR) levels for autonomous operation to achieve comparable traffic safety and efficiency. We further employ the conflation of microsimulation observations and data-driven models to design a regression model to predict LMTs as an indicator for traffic conditions using the work zone configuration as input variables. In particular, we address the heterogeneity induced by the compliance distribution of drivers by sampling the data points from the distribution to capture the diversity in compliance behaviors of the drivers. Our findings can provide insights for practitioners and researchers regarding the optimal compliance distribution using the performance measurements demonstrated in this work.

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Clarifying new urban mobility services based on a threefold business model framework

Market entrants have brought a variety of new urban mobility services over the past years, which are rooted in the sharing economy and have their origin in digitalization. Digital data serve as key resource of a business model and, accordingly, digital technologies are the basis of key activities. Building our analysis on the resource-based view and on the business model debate, we ask: what degrees of digitalization do urban mobility service business models exhibit? We perform a systematic literature review and a qualitative content analysis. As a result, we identify a continuum of highly and lowly digitalized business models. We derive a threefold business model framework, substantiated in conventional mobility, hybrid, and data-driven business models. (1) Conventional mobility business models are dominated by mobility as a key resource, digitalization is low and performed by key partners, (2) hybrid models contain both conventional mobility and data-driven key resources, and (3) data-driven models take digital data as key resources, while conventional mobility is carried out by key partners. As a first main contribution, we conceptualize conventional versus purely data-driven business models along the continuum of data-driven business model components. New urban mobility services are the group of both hybrid and data-driven business models, while conventional urban mobility stands on its own. As a second contribution, we clarify the Mobility-as-a-Service (MaaS) concept by corroborating it as a purely data-driven business model with key partners provisioning mobility.

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Extracting dashcam telemetry data for predicting energy use of electric vehicles

Prior to the acquisition of an electric vehicle, pre-evaluation of vehicle energy use is desirable to assess whether the intrinsic vehicle electrical storage capability is satisfactory. However, inconsistency in general vehicle modelling may provide unreliable predictions concerning energy usage. To increase the prediction reliability, the use of route-specific driving cycle data is essential.This paper presents a case study of a novel method of extracting vehicle telemetry data from archived dashcam videos without the need to deploy conventional telemetry techniques. Utilising dashcam videos as input, and employing image processing and recognition technology, textual en-route driving data embedded in the video can be extracted. This data can then, in-turn, be used to model the performance of the vehicle, or an electric equivalent in terms of energy use and emissions. Results from preliminary testing with real-life dashcam videos, demonstrate negligible errors with regards to energy requirements and pollutants emitted from an EV operating on the modelled routes. Consequently, the proposed solution opens up the possibility to gather a significant amount of new data in order to better assess the transport sector’s energy requirements. This is especially important for situations where conventional telemetry is difficult to obtain. In addition, results from vehicle fleet modelling may inform policy decisions with regard to the impact of introducing low emission zones.

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An Investigation of factors Influencing electric vehicles charging Needs: Machine learning approach

Decarbonization of the world is greatly contributed to by the recent technological advancements that have fostered the development of electric vehicles (EVs). The EVs relieve transportation dependence on natural fossil fuels as an energy source. More than 50 % of the petroleum products produced worldwide are estimated to be used in the transportation sector, accounting for more than 90 % of all transportation energy sources. Consequently, studies estimate thatthe transportation sector produces about 22 % of global carbon dioxide emissions, posingsignificant environmental issues. Thus,using EVs, particularly on road transport, is expected to reduce environmental pollution. To accelerate EV development and deployment, governments worldwide invest in EV development through various initiatives to make them more affordable. This research aims to investigate the changing needs of EV users to establish factors to be considered in the selection of charging demands using machine learning, usingan extreme gradient boosting model. The model reached high accuracy, with an R2-Score of 0.964 to 1.000 across all predicted needs. The model performance is greatly affected by age, median income, education, and car ownership. High values of people with high income, high education, and age between 35–54 years show a positive contribution to the model’s performance, contrary to those with 65+, low income, and low education attainment. The outcomes of this research document factors that influence EV charging needs; therefore, it provides a basis for decision-makers and all stakeholders to decide where to locate EV charging stations for usability, efficiency, sustainability, and social welfare.

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