• Energy Research

The current literature on public perceptions of autonomous vehicles focuses on potential users and the target market. However, autonomous vehicles need to operate in a mixed traffic condition, and it is essential to consider the perceptions of road users, especially vulnerable road users. This paper builds explicitly on the limitations of previous studies that did not include a wide range of road users, especially vulnerable road users who often receive less priority. Therefore, this paper considers the perceptions of vulnerable road users towards sharing roads with autonomous vehicles. The data were collected from 795 people. Extreme gradient boosting (XGBoost) and random forests are used to select the most influential independent variables. Then, a decision tree-based model is used to explore the effects of the selected most effective variables on the respondents who approve the use of public streets as a proving ground for autonomous vehicles. The results show that the effect of autonomous vehicles on traffic injuries and fatalities, being safe to share the road with autonomous vehicles, the Elaine Herzberg accident and its outcome, and maximum speed when operating in autonomous are the most influential variables. The results can be used by authorities, companies, policymakers, planners, and other stakeholders.

Between the ages of 6 and 18, children spend between 30 and 42 h a week at school, mostly indoors, where indoor environmental quality is usually deficient and does not favor learning. The difficulty of delivering indoor air quality (IAQ) in learning facilities is related to high occupancy rates and low interaction levels with windows. In non-industrialized countries, as in the cases presented, most classrooms have no mechanical ventilation, due to energy poverty and lack of normative requirements. This fact heavily impacts the indoor air quality and students’ learning outcomes. The aim of the paper is to identify the factors that determine acceptable CO2 concentrations. Therefore, it studies air quality in free-running and naturally ventilated primary schools in Chile, aiming to identify the impact of contextual, occupant, and building design factors, using CO2 concentration as a proxy for IAQ. The monitoring of CO2, temperature, and humidity revealed that indoor air CO2 concentration is above 1400 ppm most of the time, with peaks of 5000 ppm during the day, especially in winter. The statistical analysis indicates that CO2 is dependent on climate, seasonality, and indoor temperature, while it is independent of outside temperature in heated classrooms. The odds of having acceptable concentrations of CO2 are bigger when indoor temperatures are high, and there is a need to ventilate for cooling.

To ensure cities’ livability, a significant modal shift from car use towards more sustainable modes of transportation, such as walking and cycling, is required. To establish such a modal shift, a better understanding is needed of the psychological components that affect people’s likelihood of shifting to active transport modes. To this end, a behavioural survey was conducted among more than 2000 respondents across nine European cities in four countries. Using factor and cluster analysis, two groups of respondents are identified that have common determinants of their variations in intentions to shift to active transport modes, i.e., a “pro-cycling” cluster (55.6% of the respondents) and a “non-pro-cycling” cluster (44.4%). The findings highlight the intrinsically different nature of walking and cycling as transport modes, underlining the importance of distinguishing walking and cycling policies. The main obstacle to cycle more frequently is perceived traffic safety. Therefore, the main priority should be the improvement of traffic safety. The most important obstacle hindering more frequent walking is time. Hence, reducing travel time, for instance, by creating shortcuts for pedestrians and denser and more diversified urban areas will be an important strategy. Future research could extend this research to cities in other countries and regions. By repeating the survey periodically, changes in people’s motivations and perceived barriers can be analysed over time.

Walkability has become a research topic of great concern for preserving public health, especially in the era of the COVID-19 outbreak. Today more than ever, urban and transport policies, constrained by social distancing measures and travel restrictions, must be conceptualized and implemented with a particular emphasis on sustainable walkability. Most of the walkability models apply observation and subjective methods to measure walkability, whereas few studies address walkability based on sense perception. To fill this gap, we aim at investigating the perceived neighbourhood walkability (PNW) based on sense perception in a neighbourhood of Brussels. We designed a survey that integrates 22 items grouped into 5 dimensions (cleanness, visual aesthetics, landscape and nature, feeling of pressure, feeling of safety), as well as the socio-demographic attributes of the participants. Using various statistical methods, we show that socio-demographics have almost no effects on perceived neighbourhood walkability. Nonetheless, we found significant differences between groups of different educational backgrounds. Furthermore, using a binomial regression model, we found strong associations between PNW and at least one item from each grouping dimension. Finally, we show that based on a deep neural network for classification, the items have good predictive capabilities (78% of classification accuracy). These findings can help integrate sense perception into objective measurement methods of walkable environments. Additionally, policy recommendations should be targeted based on differences of perception across socio-demographic groups.

In the last few years, there has been a strong increase in the interest in and usage of so-called “Personal e-Transporters” (PeTs), also referred to as micro-mobility devices. Empirical research on the usage of PeTs as a transport mode is virtually non-existent, especially within Europe. This paper aims to fill this gap by investigating people’s motivations and barriers to the use of PeTs. To this end, a behavioural survey was conducted in nine European cities. A representative sample of approximately 250 respondents per city was collected, resulting in a dataset, after data cleaning, of 2159 observations. Generally, respondents’ perceptions of PeTs are not (yet) very favourable. Respondents’ perceptions related to cost and safety received the lowest scores. The results from the transtheoretical model of behavioural change show that a variety of factors influence the stage of behavioural change in which the respondents can be situated. These factors include cycling norms, current walking behaviour, walking attitudes, pro-environmental orientation, gender, PeTs possession, cycling obstacles and subscription to a bicycle sharing service. An important strength of this study lies in the international nature and the size of the data collection, ensuring the reliability and transferability of the results to other cities. To the best of our knowledge, it is the first large-scale survey to investigate people’s travel behaviour related to the usage of PeTs and possibly the only large-scale investigation that took place before the deployment of shared e-scooters in many European cities. Furthermore, an explicit link is made with other modes of active transport (walking and cycling).