Automated vehicles have received great attention, since they offer the possibility of significantly increasing traffic safety, mobility, and driver comfort. Current automation technology is still ...imperfect; therefore, there will still be situations in which the automation will not be able to handle and will request the driver to suspend nondriving tasks and take over control of the automated vehicle in a limited period of time. Accordingly, it is necessary to understand the effects of the lead time of take-over request as well as nondriving tasks on driver take-over. The present driving simulator experiment studied the effects of lead time and various realistic nondriving tasks on take-over behavior and driver acceptance to the automated vehicle. Results suggested optimal driver take-over performance when the lead time of the take-over request was 10-60 s for general nondriving tasks. Specifically, a take-over request with lead time at 10-60 s led to lower crash rate, greater minimum time-to-collision, and lower lateral acceleration. However, a longer lead time (e.g., 15-60 s) was necessary to achieve optimal driver acceptance even though drivers could successfully take over control with shorter lead time (e.g., 10 s). In addition, driver take over performance was significantly influenced by nondriving tasks. When more sensory modalities were occupied or when the cognitive load was very low, driver take-over performance was impaired, especially when the take-over request was too late (e.g., lead time was 3 s). Potential applications of the results in designing of take-over request in automated vehicles were further discussed.
Drivers overloaded with information significantly increase the chance of vehicle collisions. Driver workload, which is a multidimensional variable, is measured by both performance-based and ...subjective measurements and affected by driver age differences. Few existing computational models are able to cover these major properties of driver workload or simulate subjective mental workload and human performance at the same time. We describe a new computational approach in modeling driver performance and workload-a queuing network approach based on the queuing network theory of human performance and neuroscience discoveries. This modeling approach not only successfully models the mental workload measured by the six National Aeronautic and Space Administration Task Load Index workload scales in terms of subnetwork utilization but also simulates the driving performance, reflecting mental workload from both subjective- and performance-based measurements. In addition, it models age differences in workload and performance and allows us to visualize driver mental workload in real time. Further usage and implementation of the model in designing intelligent and adaptive in-vehicle systems are discussed.
Automated vehicles offer the possibility of significantly increasing traffic safety, mobility, and driver comfort, and reducing congestion and fuel emissions. Current automation technology, however, ...remains imperfect, and in certain situations, automation will still require the driver to suspend non-driving tasks and take back control of the automated vehicle in a limited period of time. During automated driving, drivers engaged in non-driving tasks (e.g., reading, taking a nap) may not perceive the visual or auditory take-over request in a timely nor accurate manner. Therefore, it is necessary to explore the potential of tactile warning further. This study investigates the effects of vibration patterns of take-over requests (six vibration patterns with different orders of the vibration location) and various realistic non-driving tasks (six non-driving tasks: reading, typing, watching videos, playing games, taking a nap, and monitoring the driving scenario on the driving simulator) on driver take-over behavior, and driver trust and acceptance of automated vehicles. Across all non-driving tasks, the fastest response time was observed with Vibration Pattern 5 (order of the vibration location: back-back-seat-seat). The shortest response time and largest minimum time-to-collision (TTC) also were observed when drivers took back control of the vehicle after monitoring the driving scenario. No interaction effects between vibration patterns and non-driving tasks were observed. Potential applications of the results of designing take-over requests in automated vehicles are discussed.
•We use a dual process framework to model mindfulness-performance link.•We test the model on safety performance of nuclear power plants operators.•Dispositional mindfulness predicts performance over ...contentiousness.•The mindfulness-performance link is more positive among intelligent operators.•The mindfulness-performance link is more positive among experienced operators.
Based on the dual process model of human cognition, this study investigated the influence of dispositional mindfulness on operators’ safety behaviors and its boundary conditions. In a sample of 212 nuclear power plant control room operators, it was found that both safety compliance and safety participation behaviors were positively influenced by dispositional mindfulness as measured by the 14-item Freiburg Mindfulness Inventory. This effect was still positive after controlling for age, intelligence, work experience and conscientiousness. Moreover, two boundary conditions were identified: the impact of dispositional mindfulness of safety behaviors was stronger among operators who were either more experienced or more intelligent. Theoretically, the framework we used to understand the benefit of mindfulness on safety behaviors has been proved to be useful. Practically, it provides a new and valid criterion that could be used in operators’ selection and training program to improve organizational safety.
Reducing carbon emission intensity is crucial for achieving sustainable development. Carbon emission intensity is expressively affected by the issuance of green bonds. Thus, it is imperative to ...assess the influence of green bond issuance on carbon emissions and examine their correlation. Such research holds great potential to expedite the overhaul and modernization of businesses and to construct a circular economy system. This paper uses the spatial Durbin model to draw empirical conclusions by using data from 26 provinces in China between 2016 and 2021. Firstly, under different spatial matrices, it has been analyzed that an increase of 1% in the issuance of green bonds leads to a reduction of 0.306% or 0.331% in carbon emission intensity. It shows that green bonds have the potential to substantially reduce carbon intensity. Additionally, the intensity of emissions in the current period is driven by the intensity of emissions in the previous period. Secondly, the analysis of mediated transmission suggests that green bonds can ultimately reduce carbon emission intensity by changing the energy consumption structure or improving the efficiency of green technology innovation. Thirdly, the analysis of heterogeneity shows that the inhibitory effect of green bond issuance on carbon emissions is stronger in less economically developed regions than in economically developed regions. There is a significant inhibitory effect of green bond issuance in neighboring provinces on local carbon emission intensity. This effect is present only in provinces in less economically developed regions and not in economically developed regions.
A long landing is one type of flight incident that will multiply the risk of a runway excursion. It occurs frequently but receives little attention in research due to difficulty in obtaining the real ...flight data. The aim of this paper is to discover key flight parameter features of long landing incidents by analyzing Quick Access Recorder (QAR) data and put forward prevention measures from the perspective of pilot operation at the same time. First, 73 flight performance parameter variables and 4 operation parameter variables were defined, covering major landing stages from 1500ft to touchdown. Then 128 cases of selected QAR data were divided into two groups according to the threshold of identifying normal and long landing. Second, each flight parameter variable of these 128 flights was compared between groups and then the logistic and linear regression models were developed respectively to further examine the links between touchdown distance and these flight parameter variables. Third, potential flight operation causing performance difference of long landing incidents was also analyzed. Finally results indicate that the period of 200ft to touchdown is the key stage of landing and flare is the most critical operation affecting touchdown distance. It is suggested that the pilot should inspect the ratio of descent rate and groundspeed carefully at the height of 50ft and pilot׳s faster and steady pulling up columns is probably helpful for an excellent flare and landing. The findings are expected to be applied into flight operation practice for further preventing long landing incidents and even the runway excursion accidents.
This paper presents a new computational framework for early detection of driver distractions (map viewing) using brain activity measured by electroencephalographic (EEG) signals. Compared with most ...studies in the literature, which are mainly focused on the classification of distracted and nondistracted periods, this study proposes a new framework to prospectively predict the start and end of a distraction period, defined by map viewing. The proposed prediction algorithm was tested on a data set of continuous EEG signals recorded from 24 subjects. During the EEG recordings, the subjects were asked to drive from an initial position to a destination using a city map in a simulated driving environment. The overall accuracy values for the prediction of the start and the end of map viewing were 81% and 70%, respectively. The experimental results demonstrated that the proposed algorithm can predict the start and end of map viewing with relatively high accuracy and can be generalized to individual subjects. The outcome of this study has a high potential to improve the design of future intelligent navigation systems. Prediction of the start of map viewing can be used to provide route information based on a driver's needs and consequently avoid map-viewing activities. Prediction of the end of map viewing can be used to provide warnings for potential long map-viewing durations. Further development of the proposed framework and its applications in driver-distraction predictions are also discussed.
•The baseline driver yielding rate is only 3.5%.•The study proposed 11 gestures and selected four gestures after driver evaluation.•The gesture L-bent-level leads to more than tripled driver yielding ...rate.•Drivers passing by with unchanged speed decreased from 63.5% to 38.8%.•No significant side effects of the gesture in terms of horn use and lane change.
To protect pedestrians, many countries give them priority at uncontrolled mid-block crosswalks or pedestrian crossings. However, the actual driver yielding rate is not always satisfactory (only 3.5% in this study). To increase the yielding rate, this study proposed eleven pedestrian gestures to inform drivers of their intent to cross. The gestures were evaluated based on the process of human interaction with environment. Four gestures were selected as candidates to test in field experiments based on scores for visibility, clarity, familiarity and courtesy (see illustration in Fig. 2): (1) right elbow bent with hands erect and palm facing left (R-bent-erect), (2) left elbow bent with hands level and palm facing left (L-bent-level), (3) left arm extended straight to left side with palm erect facing left (L-straight-erect), and (4) a ‘T’ gesture for “Time-out”. In the experiment, confederate pedestrians waiting at the roadside displayed the gestures (baseline: no gesture) to 420 vehicles at 5 sites in Beijing, China. When pedestrians used the L-bent-level gesture, the vehicle yielding rate more than tripled of that in the baseline condition. The L-bent-level gesture also resulted in a significant decrease in driving with unchanged speed (63.5–38.8%) and had no significant side effects in terms of drivers’ horn use or lane changing. The effects of such gestures in other contexts such as when pedestrians are in the crosswalk and when they are interacting with turning vehicles are discussed, together with the applications in training vulnerable pedestrian groups (children or elderly) and facilitating pedestrian detection by drivers.
► Explored the effect of sunshields installed at intersections on reducing red light running behavior of riders. ► An observational study of 2477 riders was conducted. ► Sunshields can reduce the ...likelihood of red light infringement of cyclists and e-bike riders on both sunny and cloudy days. ► Sunshields might be an affordable way to improve rider safety for those areas or countries with a torrid climate.
Bicycles held an important position in transportation of China and other developing countries. As accidents rate involving electronic and regular bicycles is increasing, the severity of the bicycle safety problem should be paid more attention to. The current research explored the effect of sunshields (a kind of affordable traffic facility built on stop line of non-motor vehicle lanes (According to National Standard in China, e-bikes share the non-motor vehicle lane with regular bikes.) which was undertaken to avoid riders suffering from sunlight and high temperature) on diminishing red light running behavior of cyclists and e-bike riders. An observational study of 2477 riders was conducted to record and analyze their crossing behaviors at two sites across the city of Hangzhou, China. Results from logistic regression and analysis of variance indicated a significant effect of sunshield on reducing red light infringement rate both on sunny and cloudy days, while this effect of sunshield was larger on sunny days than on cloudy days based on further analysis. The effect of intersection type in logistic regression showed that riders were 1.376 times more likely to run through a red light upon approaching the intersection without sunshields compared to with sunshields in general. The results of MANCOVA further confirmed that rates of running behaviors against red lights were significantly lower at the intersections with a sunshield than at intersections without sunshields when other factors including traffic flow were statistically controlled. To sum up, it is concluded that sunshields installed at intersections can reduce the likelihood of red light infringement of cyclists and e-bike riders on both sunny and cloudy days. For those areas or countries with a torrid climate, sunshield might be a recommended facility which offers an affordable way to improve the safety of cyclists and e-bike riders at intersections. Limitations of the current sunshield design and current study are also discussed.
The quantitative prediction and understanding of a driver's speed control is an essential component in preventing speeding and designing of vehicle systems. Driver speed control is a complex behavior ...of longitudinal vehicle control consisting of speed perception, decision making, motor control, vehicle dynamics modeling, and individual driver differences. However, there are few existing models that can integrate all of these aspects in a cohesive manner. To address this problem, this paper introduces a mathematical model for a driver's speed control with analytical solutions based on human cognitive mechanisms in driving. This model includes an integrated queuing network-model human processor structure and the rule-based decision field theory. This new model consequently can predict several aspects of driver speed control behavior at the same time, such as driving speed, throttle/brake pedal angle, acceleration, and the frequency of speedometer inspection. A laboratory session involving a driving simulator is conducted to validate the current model. The model accounted for over 99% of the experimental speed of the average driver, and over 95% of the experimental speed for the majority of individual drivers.
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