Effects of hands-free cellular phone conversational cognitive tasks on driving stability based on driving simulation experiment

Driver distraction due to cellular phone usage is a major contributing factor to road crashes. This study compares the effects of conversational cognitive tasks using hands-free cellular phone on driving performance under three distraction conditions: (1) no distraction (no cellular conversation), (2) normal conversation (non-emotional cellular conversation), and (3) seven-level mathematical calculations. A car-following scenario was implemented using a driving simulator. Thirty young drivers with an average age of 24.1 years maintained a constant speed and distance between the subject vehicle and a leading vehicle on the driving simulator, and then respond to the leading vehicle’s emergency stop. The driving performances were assessed by collecting and statistically analyzing several variables of maneuver stability: the drivers’ brake reaction times, driving speed fluctuation, car-following distance undulation, and car-following time-headway undulation. The results revealed that normal conversation on a hands-free cellular phone impaired driving performance. The degree of impairment caused by normal calculation was equivalent to the distraction caused by Level 3 mathematical calculations according to the seven-level calculation baseline. The calculation difficulty of Level 3 is one double-digit figure plus a single-digit figure, and non-carry addition mental arithmetic is required, e.g., 44 + 4. The results indicated that an increase in the level of complexity of the calculation task was associated with an increase in brake reaction time. The seven-level calculation-task baseline could be applied to measure additional distraction effects on driving performance for further comparison.     

The influence of attention allocation and age on intersection accidents

Many severe accidents occur in urban areas. As part of the research project UR:BAN, this study investigated the causes of driver errors (e.g., inadequate attention allocation) in urban areas when turning left at intersections. As intersection accidents are especially difficult for older drivers, differences between older and younger drivers were examined as well. In a first step, accident protocols of left turn crashes with pedestrians and bicyclists were analysed in detail, since they are the most dangerous ones. Characteristics of the oncoming traffic and the location of crossing bicyclists and pedestrians were identified as possible causes. Accordingly, critical scenarios were implemented in a static driving simulator, varying the characteristics of the oncoming traffic, the direction and location of crossing vulnerable road users. These factors were examined in a within-subject design, with two different aged groups of participants (12 aged 20–35 y, 12 aged 65+ y; between-subjects factor).The results revealed that the presence of the oncoming traffic, which was assumed to capture the drivers’ attention, did not lead to more accidents with vulnerable road users. However, this may be because many drivers waited until the oncoming traffic had passed. Unexpectedly, older drivers had fewer accidents. This may be explained by the more cautious behaviour of older drivers, who drove significantly slower and waited significantly longer at the stop line before turning. Further analyses showed that a more cautious behaviour, independently of the age, predicted accident avoidance better than attention allocation. From these results, warning systems for younger and older drivers, especially for those not driving cautious, need to be developed. This idea will be tested in future studies introducing different warning concepts.     

Parents’ perceptions of the Family Climate for Road Safety: Associations with parents’ self-efficacy and attitudes toward accompanied driving,and teens’ driving styles

In order to better understand parental influence on teen driving, a series of three studies were conducted among parents of young drivers to examine the association between their scores on the Family Climate for Road Safety Scale (FCRSS; Taubman – Ben-Ari & Katz – Ben-Ami, 2013) and three relevant factors: parental self-efficacy (Study 1, n = 101); parents’ attitudes toward accompanied driving (Study 2, n = 100); and teen’s driving styles (Study 3, n = 235 parents–young drivers pairs). The findings of Study 1 revealed significant associations between parents’ scores on the positive FCRSS dimensions and their self-reported parental competence. In addition, parents’ lack of commitment to safe driving was related to lower parental self-efficacy. Study 2 indicated significant associations between parents’ scores on the positive FCRSS dimensions and the positive attitude of relatedness during the accompanied driving phase. Negative associations were found between these FCRSS dimensions and negative perceptions of the accompanied driving phase (i.e., tension, disapproval, and avoidance). The findings of Study 3 showed significant associations between parents’ scores on the positive FCRSS dimensions and their offspring’s careful driving style, as well as negative associations between these dimensions and offspring’s endorsement of the reckless, angry, and anxious driving styles. Taken together, the results indicate the importance of the family climate as part of a global understanding of the dynamic surrounding youngsters’ driving. Furthermore, they show that the particular driving-related family climate is associated not only with parents’ self-perceptions and conduct in the early stages of their children’s driving (the accompanied driving phase of a GDL), but also impacts the way teenagers ultimately choose to drive, when they are on their own. Implications for interventions are discussed.     

Recovery from post‐traumatic stress disorder in children following road traffic accidents: the role of talking and feeling understood

Forty children were assessed 6 weeks and 8 months after involvement in a road traffic accident (RTA). Ten of the 21 children suffering post‐traumatic stress disorder (PTSD) at 6 weeks continued to fulfil diagnostic criteria at 8 months. There was no evidence of delayed onset of PTSD in children who had not developed this condition at 6 weeks. Talking about the accident and feeling understood were associated with recovery. Providing children with opportunities to talk about their accident may be helpful in preventing or reducing psychological distress. Copyright © 2001 John Wiley & Sons, Ltd.     

Hazard perception abilities of experienced and novice motorcyclists: An interactive simulator experiment

This study reports an experiment that compared the hazard perception abilities of experienced and novice motorcycle riders using an interactive, closed-loop, simulator. Participants (n = 49) were categorized into four groups: experienced motorcycle riders with full driver licence, inexperienced motorcycle riders with full driver licence, novice motorcycle riders with full driver licence, and novice motorcycle riders with probationary driver licence. The participants were tested on three scenarios, each consisting of eight hazardous events. They were instructed to ride normally, but to respond appropriately to avoid the hazards. Under certain conditions in the simulator, we found that experienced riders (relative to inexperienced or novice riders) crashed less often, received better performance evaluations, and approached hazards at more appropriate speeds. Interestingly, we also found that some novice riders were overconfident in their riding ability. We discuss how this overconfidence might be related to hazard perception.     

浅论管子经济思想对《歧路灯》的影响

《歧路灯》中所表现出的既重视农业又鼓励工商业发展以及尊重农民与工商业者的经济思想与管子的相关经济思想有着一脉相承的关系。而正是管子经济思想中这种进步的方面,促使李绿园从实际出发,以朴素的唯物主义态度对熏陶自己很深的儒家思想作出了一定的反思,并在一定程度上冲破了它的桎梏,其精神确实是难能可贵的。这说明他的确不是一位腐儒,其思想中存在着某些进步的因子。     

After you?! – Use of external human-machine interfaces in road bottleneck scenarios

In the near future, automated vehicles (AVs) will enter the urban transport system. This fact will lead to mixed traffic consisting of AVs, human car drivers and vulnerable road users. Since the AV’s passenger no longer has to monitor the driving scene, conventional communication does not exist anymore, which is essential for traffic efficiency and safety. In research, there are plenty of studies focusing on how AVs could communicate with pedestrians. One approach is to use external human-machine interfaces (eHMIs) on the AV’s surface. In contrast to the studies dealing with AV-pedestrian communication, this paper focuses on communication strategies of AVs with drivers of regular vehicles in different road bottleneck scenarios. The eHMI development and design is building on previously defined requirements and on fundamentals of human visual perception. After designing several eHMI drafts, we conducted a user survey with 29 participants resulting in the final eHMI concept. The evaluation of the evolved eHMI was conducted in a driving simulator experiment with 43 participants investigating the AV-human driver interaction at road bottlenecks. The participants were assigned either to the experimental group being faced with the eHMI or to the baseline group without explicit communication. The results show significantly shorter passing times and fewer crashes among the human drivers in the group with the eHMI. Additionally, the paper researches the aftereffects of an automation failure, where the AV first yields the right of way and then changes its strategy and insisted on priority. Experiencing the automation failure is reflected in increased passing times, reduced acceptance ratings and a lower perceived usefulness. In conclusion, especially in unregulated bottleneck scenarios flawless communication via eHMIs increases traffic efficiency and safety.     

A qualitative study of young drivers and deterrence based road policing

Deterrence theory is the predominant theory used to underpin road policing initiatives. However, survey research indicates that this approach may not be as effective for young drivers. This study uses focus groups, conducted in both metropolitan and regional locations in two Australian states (Queensland and Victoria), to explore three components of classical deterrence theory: certainty, severity & swiftness. The results suggest that geographical context affected perceptions of certainty with individuals from regional locations less likely to indicate that they would be caught by police for committing a traffic offence. Additionally, the use of cameras to detect road offences increased perceptions of certainty for young drivers. The results of this study suggest that police agencies should focus on undertaking actions to increase the perceptions of certainty swiftness and severity of punishment, particularly in regional areas, for young drivers who engage in illegal behaviour on the road. Where appropriate, these actions should take into account the geographical context. There may also be value in considering augmenting deterrence theory with other theoretical perspectives for this group.     

The effectiveness of “Soft-blocking” for reducing clicking on-screen while driving

Smartphone usage while driving is recognized as a compromise on road safety. We investigated if silencing and hiding of notifications from drivers (soft blocking) can reduce clicks on the screen while driving and if the effect of the soft blocking would be different for different speed thresholds (STs) (i.e., at driving speed greater than 0 km/h, greater than 1 km/h….and greater than 90 km/h). Drivers installed a smartphone application, which continuously monitored their phones. In the intervention group (N = 22), the application switched to the soft blocking mode during the study's intervention period, while in the control group (N = 29) it remained in a recording-only mode. We ran a Poisson regression model on the click events frequency (CEF) to estimate the soft blocking effect for each of the STs between 0 and 90 km/h. Our analyses indicated that the soft blocking effectiveness was indeed speed-dependent and pointed to a decline in CEF from ST > 55 km/h and to mixed results if ST < 55 km/h. We identify a potential of soft blocking to reduce phone usage while driving and recommend ST-dependent soft blocking. We also recommend using different STs in future investigations on the effectiveness of soft blocking.