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The COVID-19 pandemic has been a worldwide disruptive event that impacted, to a greater or lesser extent, all countries and economic activities. In the transport sector, stakeholders are still dealing with and learning from its consequences, as many users have changed their preferences towards private and less sustainable modes. In this paper, a mixed logit modelling approach was applied to a vast database from a stated preference survey conducted in Germany to assess the influence of COVID-19 on mobility preferences in three different stages of the pandemic period: lockdown (high-risk of spread, May 2020), post-lockdown (medium risk of spread, June 2020), and a period where the number of infected cases was lower (small risk of spread, October 2020). Several variables were included in the analysis, such as sociodemographic characteristics, mobility habits and preferences regarding future mobility solutions. Three models were developed, one for each pandemic stage. A comprehensive and reflective analysis of the models’ results, aligned with other studies’ findings, shows that the utility of public transport (PuT) and bicycles, based on individuals’ sociodemographic characteristics and choice attributes, compared to cars was affected by the pandemic state. Regarding the influence of crowding inside PuT during the different periods, it was concluded that users are more willing to pay an extra for their monthly passes to have available seats in PuT in the latter stage of the pandemic. The availability of dedicated bike lanes and a shower at the destination were considered attractive factors for cycling during the lockdown phase. Regarding the private car use, the cost of parking is the only attribute that demonstrates a causal effect on the preference for using this mode. This attribute holds a greater relevance during the post-lockdown and “new normal” periods. The results of this study can be helpful to guide policymakers on the definition of actions to counteract the increasing preference for private transport in the future and during disruptions.

Abstract Introduction In a context of increasing automation of road transport, many researchers have been dedicated to analyse the risks and safety implications of resuming the manual control of a vehicle after a period of automated driving. This paper performs a systematic review about drivers’ performance during takeover manoeuvres in driving simulator, a tool that is widely used in the evaluation of automated systems to reproduce risky situations that would not be possible to test in real roads. Objectives The main objectives are to provide a framework for the main strategies, experimental conditions and results obtained by takeover research using driving simulation, as well as to find whether different approaches may lead to different outcomes. Methodology First, a literature search following the PRISMA statement guidelines and checklist resulted in 36 relevant papers, which were described in detail according to the type of scenarios and takeover events, drivers’ engagement in secondary tasks and the assessed takeover performance measures. Then, those papers were included in a meta-analysis combining PAM clustering and ANOVA techniques to find patterns among the experimental conditions and to determine if those patterns have influence on the observed takeover performance. Conclusions Less complex experiments without secondary task engagement and conducted in low-fidelity simulators are associated with lower takeover times and crash rates. The takeover time increases with the time budget of the first alert, which reduces the pressure for a driver’s quick intervention.

This study explores attitudes towards urban air mobility (UAM) for e-commerce deliveries. UAM, which utilizes drones, has the potential to revolutionize transport services and logistics, leading to economic benefits and reductions in congestion and pollution. However, public acceptance is crucial for a successful implementation; thus, understanding the people’s perspective is key. Descriptive statistics were employed to evaluate survey results from three different European regions, followed by a cluster analysis to define potential user profiles. This study revealed slightly different perceptions towards UAM between the analyzed regions, but also a generally positive attitude. The most important expected identified benefits from UAM were a decrease in congestion and pollution in city centers. High-acceptance segments are gender-balanced and correspond mostly to active population and frequent online shoppers that perceive value in drone deliveries, especially related to an increased convenience and speed. They support public investment in UAM and are willing to pay more for these services and to have their home flown over. Opposite attitudes were expressed by low-acceptance segments, which are female-dominated and include mostly non-frequent online shoppers. The identified user profiles in this study can support the development of public policy and marketing strategies to increase acceptance and adoption.

In this paper, a different Fiber Loop Mirror (FLM) configuration with two circulators is presented. This configuration is demonstrated and characterized for sensing applications. This new design concept was used for strain and torsion discrimination. For strain measurement, the interference fringe displacement has a sensitivity of (0.576 ± 0.009) pm‧με−1. When the FFT (Fast Fourier Transformer) is calculated and the frequency shift and signal amplitude are monitored, the sensitivities are (−2.1 ± 0.3) × 10−4 nm−1 με−1 and (4.9 ± 0.3) × 10−7 με−1, respectively. For the characterization in torsion, an FFT peaks variation of (−2.177 ± 0.002) × 10−12 nm−1/° and an amplitude variation of (1.02 ± 0.06) × 10−3/° are achieved. This configuration allows the use of a wide range of fiber lengths and with different refractive indices for controlling the free spectral range (FSR) and achieving refractive index differences, i.e., birefringence, higher than 10−2, which is essential for the development of high sensitivity physical parameter sensors, such as operating on the Vernier effect. Furthermore, this FLM configuration allows the system to be balanced, which is not possible with traditional FLMs.

The over-exploitation of coastal aquifers has led to seawater intrusion issues in many parts of the globe; this problem, which is associated with water recharge deficit and anthropogenic pollution, represents the main source of groundwater degradation in Santiago Island in the Republic of Cape Verde’s archipelago. Brackish groundwater for agriculture and human consumption is being provided to several areas on Santiago Island as the only type of available water. Chemical and isotopic data obtained in three main groundwater systems were used in the characterization of the groundwater resources and in the identification of the main source responsible for their degradation. The obtained results indicate water–rock interaction as the major process responsible for the groundwater quality reflecting its lithological composition. Carbonatite dissolution can be partially responsible for the calcium increase along the groundwater flow path. Isotopic data (δ2H, δ18O; 3H and 14C) combined with the water chemistry provided a wide characterization of the groundwater recharge and identification of salinization processes (like seawater intrusion and marine aerosols dissolution in different sectors of the island). In the eastern part of Santiago Island, a different isotopic pattern (2H-18O) was observed in the groundwater samples, which was likely ascribed to different climate conditions. Carbon-14 determinations indicate apparent groundwater ages between 3.5 and 5.1 ka BP.

Spontaneous heterotopic pregnancies occur in about 1/30000 pregnancies, with the ovarian subtype comprising 2.3% of the total.We report the case of a healthy 32-year-old woman, gravida 4, para 3, who presented to the emergency room with severe abdominal pain. Two weeks earlier, pelvic ultrasound had revealed a 6-week intrauterine pregnancy. She was hemodynamically stable, but had rebound tenderness on the right iliac fossa. Transvaginal ultrasound revealed an evolutive intrauterine pregnancy with a gestational age (GA) of 8 weeks, with a synchronous evolutive adnexal pregnancy of the same GA and some free fluid in the pouch of Douglas. She underwent an urgent laparoscopy which showed an intact gestational sac containing an embryo on the right ovary associated with mild hemoperitoneum. An ovarian wedge resection was performed to preserve ovarian tissue. The intrauterine pregnancy had no complications and the patient delivered vaginally at term.Heterotopic pregnancy is potentially life-threatening. Despite being extremely rare after natural conception, and even more so in the absence of major risk factors, it should be considered in any pregnant woman with abdominal pain. A high index of suspicion is important for a prompt diagnosis, selection of the appropriate surgical treatment and successful obstetric outcomes. Keywords: Heterotopic pregnancy, Ovarian pregnancy, Laparoscopic management

Driver inattention is a major contributor to road crashes. The emerging of new driver monitoring systems represents an opportunity for researchers to explore new data sources to understand driver inattention, even if the technology was not developed with this purpose in mind. This study is based on retrospective data obtained from two driver monitoring systems to study distraction and drowsiness risk factors. The data includes information about the trips performed by 330 drivers and corresponding distraction and drowsiness alerts emitted by the systems. The drivers’ historical travel data allowed defining two groups with different mobility patterns (short-distance and long-distance drivers) through a cluster analysis. Then, the impacts of the driver’s profile and trip characteristics (e.g., driving time, average speed, and breaking time and frequency) on inattention were analyzed using ordered probit models. The results show that long-distance drivers, typically associated with professionals, are less prone to distraction and drowsiness than short-distance drivers. The driving time increases the probability of inattention, while the breaking frequency is more important to mitigate inattention than the breaking time. Higher average speeds increase the inattention risk, being associated with road facilities featuring a monotonous driving environment.

Most of the existing operating speed statistical models are applicable to individual design elements, particularly horizontal curves and tangents. A segment approach to operating speed has rarely been followed, with a few exceptions mainly related to the performance assessment of urban and freeway corridors, or design consistency studies using speed profiles built from successive design elements. This study introduces a new model to predict operating speeds in segments of two-lane highways. The maximum operating speed is given by a stochastic frontier function of the average daily traffic and road geometrics; the asymmetric disturbance accounts for the diversity in drivers’ behaviour and vehicle characteristics, allowing estimating any percentile speed. The model was calibrated using probe vehicle data from noncongested roads. The accuracy of the average daily traffic in representing the actual driving conditions was further validated using simultaneous speed-traffic measurements. The new model aims to assist practitioners in the evaluation of design consistency from a macroscopic perspective since the early stages of road planning and design, as well as to support the definition of speed limits at new or existing infrastructures.

The intrinsic advantages of optical sensor technology are very appealing for high voltage applications and can become a valuable asset in a new generation of smart grids. In this paper the authors present a review of optical sensors technologies for electrical current metering in high voltage applications. A brief historical overview is given together with a more detailed focus on recent developments. Technologies addressed include all fiber sensors, bulk magneto-optical sensors, piezoelectric transducers, magnetic force sensors and hybrid sensors. The physical principles and main advantages and disadvantages are discussed. Configurations and strategies to overcome common problems, such as interference from external currents and magnetic fields induced linear birefringence and others are discussed. The state-of-the-art is presented including commercial available systems.

Neste artigo, apresenta-se uma metodologia para a avaliação macroscópica da influência das características geométricas e ambientais e da sinalização de velocidade limite legal na velocidade em regime livre praticada pelos condutores em zonas periurbanas ou de transição. Um condutor circula em regime livre quando a sua escolha de velocidade não é condicionada pela presença do veículo precedente. Assim, a velocidade adotada reflete a sua resposta face às características da estrada e do ambiente envolvente. A metodologia consiste na utilização de métodos estatísticos de análise de dados multivariados, nomeadamente de classificação e de análise em componentes principais, para a definição de variáveis macroscópicas caracterizadoras das zonas periurbanas, sobre as quais é depois efetuada uma análise de regressão que permite a avaliação dos impactos das diferentes variáveis na velocidade em regime livre. A metodologia proposta é aplicada a um conjunto de 27 locais pertencentes a estradas de duas vias situadas em Portugal, onde foram observadas as velocidades praticadas, a existência de sinalização de limite legal de velocidade e diversas variáveis microscópicas caracterizadoras da geometria e do ambiente. Abstract: This paper presents a new methodology for the evaluation of the effects of posted speed limit, geometric and environmental characteristics on free-flow speed in transition zones, through a macroscopic analysis. A vehicle travels under free-flow conditions if its chosen speed is not affected by the presence of the vehicle ahead. In this sense, the free-flow speed reflects the driver’s response to road geometric and environmental characteristics. In the first stage of the proposed methodology, new macroscopic variables reflecting the characteristics of transition zones are created through the use of multivariate data analysis techniques, namely analysis of clusters and principal component analysis. In the second stage, a regression analysis is performed in order to compare the effects of different variables on the adopted free-flow speed. This methodology is then tested for a set of 27 sites located in Portuguese two-lane highways, where drivers’ speed, the existence of posted speed limit and some geometric and environmental microscopic characteristics were collected.