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271.
Considering that deaths and injuries due to run overs near pedestrian bridges (PB) are preventable events, this research aims to analyze the factors related to the use of pedestrian bridges in students of a public university of Honduras. This was made through a quantitative methodology; 330 questionnaires were applied to a sample of university students. Results suggest that 17.27% of the respondents don’t use the bridge. Most respondents (62.42%) believe it’s faster to cross the street and that using the bridge is tiresome (79.90%). Pedestrian bridges are also considered to be unsafe places, prone to robberies. Pearson’s r coefficient determined that this belief is significantly associated with the perception of cleanliness, quality of the infrastructure and illumination. There is a correlation between stress and considering the use of the bridge as a tiresome activity. A logistic regression model determined that significant variables explained the use of the PB included: being in a hurry, believing it’s faster to cross the street, thinking that PBs have a bad infrastructure, laziness and thinking that using the PB is tiresome, all of them reducing the chance that someone will use the bridge. On the other hand, non-significant variables in the model included: age, considering that using the PB is stressful, thinking that crossing the street is stressful, thinking PBs have good illumination. Safety related variables were not able to discriminate between users and non-users. These results are discussed in the light of previous research and their implication for public policy and future research. 相似文献
272.
Roundabouts are one of the most used road intersections because, compared to signalized ones, they reduce conflict points between traffic flows and moderate driving speed. Great attention should also be paid to vulnerable road users at roundabouts. According to accident statistics, in fact, accessibility of pedestrians and cyclists is not always ensured.This paper has evaluated the effects on the visibility of pedestrian crossing before and after the displacement of zebra markings, moved before intersections, and the introduction of media refuge islands and “Yield here to pedestrians” vertical signs. The above effects have been assessed by before-after analysis of speed and visual behaviour of drivers approaching the crosswalk.Moreover, the analysis of the drivers’ eye movements has highlighted the most salient elements of the pedestrian crossing. The relation between the drivers’ visual behaviour and the vehicle speed have also been calculated. Results have confirmed that the intervention carried out has increased both visibility and safety of the studied pedestrian crosswalks.Zebra markings and the median refuge island have turned out to be the most glanced elements, respectively seen by 93.75% and 56.25% of the drivers, followed by the “Yield here to pedestrians” vertical sign. The mean distance of first fixation of the crosswalk increased from 21.98 m before the intervention, to 40.69 m after it. The drivers perceived the pedestrian crossings from a longer distance after the intervention, and they continued to glance at the crosswalk while approaching it, enhancing their visual attention. 相似文献
273.
BackgroundNature offers numerous examples of animal species exhibiting harmonious collective movement. Unfortunately, the motorized Homo sapiens sapiens is not included and pays a price for it. Too often, drivers who simply follow other drivers are caught in the worst road threat after a crash: congestions. In the past, the solution to this problem has gone hand in hand with infrastructure investment. However, approaches such as the Nagoya Paradigm propose now to see congestion as the consequence of multiple interacting particles whose disturbances are transmitted in a waveform. This view clashes with a longlasting assumption ordering traffic flows, the rational driver postulate (i.e., drivers’ alleged propensity to maintain a safe distance). Rather than a mere coincidence, the worldwide adoption of the safety-distance tenet and the worldwide presence of congestion emerge now as cause and effect. Nevertheless, nothing in the drivers’ endowment impedes the adoption of other car-following (CF) strategies. The present study questions the a priori of safety-distance, comparing two elementary CF strategies, Driving to keep Distance (DD), that still prevails worldwide, and Driving to keep Inertia (DI), a complementary CF technique that offsets traffic waves disturbances, ensuring uninterrupted traffic flows. By asking drivers to drive DD and DI, we aim to characterize both CF strategies, comparing their effects on the individual driver (how he drives, how he feels, what he pays attention to) and also on the road space occupied by a platoon of DD robot-followers.MethodsThirty drivers (50% women) were invited to adopt DD/DI in a driving simulator following a swinging leader. The design was a repeated measures model controlling for order. The CF technique, DD or DI, was the within-subject factor. Order (DD-DI / DI-DD) was the between-subjects factor. There were four blocks of dependent measures: individual driving performance (accelerations, decelerations, crashes, distance to lead vehicle, speed and fuel consumption), emotional dimensions (measures of skin conductance and self-reports of affective states concerning valence, arousal, and dominance), and visual behavior (fixations count and average duration, dwell times, and revisits) concerning three regions of the driving scene (the Top Rear Car –TRC- or the Bottom Rear Car –BRC- of the leading vehicle and the surrounding White Space Area -WSA). The final block concerned the road space occupied by a platoon of 8 virtual DD followers.ResultsDrivers easily understood and applied DD/DI as required, switching back and forth between the two. Average speeds for DD/DI were similar, but DD drivers exhibited a greater number of accelerations, decelerations, speed variability, and crashes. Conversely, DI required greater CF distance, that was dynamically adjusted, and spent less fuel. Valence was similar, but DI drivers felt less aroused and more dominant. When driving DD visual scan was centered on the leader’s BRC, whereas DI elicited more attention to WSA (i.e., adopting wider vision angles). In spite of DI requiring more CF distance, the resulting road space occupied between the leader and the 8th DD robot was greater when driving DD. 相似文献
274.
Appropriate visual behaviour is necessary for safe driving. Many previous studies have found that when performing non-visual cognitive tasks, drivers typically display an increased amount of on-path glances, along with a deteriorated visual scanning pattern towards potential hazards at locations outside their future travel path (off-path locations). This is often referred to as a gaze concentration effect. However, what has not been explored is more precisely how and when gaze concentration arises in relation to the cognitive task, and to what extent the timing of glances towards traffic-situation relevant off-path locations is affected. To investigate these specific topics, a driving simulator study was carried out. Car drivers’ visual behaviour during execution of a cognitive task (n-back) was studied during two traffic scenarios; one when driving through an intersection and one when passing a hidden exit. Aside from the expected gaze concentration effect, several novel findings that may explain this effect were observed. It was found that gaze shifts from an on-path to an off-path location were inhibited during increased cognitive load. However, gaze shifts in the other direction, that is, from an off-path to an on-path location, remained unaffected. This resulted in on-path glances increasing in duration, while off-path glances decreased in number. Furthermore, the inhibited off-path glances were typically not compensated for later. That is, off-path glances were cancelled, not delayed. This was the case both in relation to the cognitive task (near-term) and the traffic environment (far-term). There was thus a general reduction in the number of glances towards situationally relevant off-path locations, but the timing of the remaining glances was unaffected. These findings provide a deeper understanding of the mechanism behind gaze concentration and can contribute to both understanding and prediction of safety relevant effects of cognitive load in car drivers. 相似文献
275.
Previous research showed that penalty-takers’ body language affects the impressions goalkeepers form about them. Furthermore, it is often assumed that body language influences goalkeepers’ performance. However, as yet, there is no empirical evidence that indicates whether this latter effect exists. The present research was aimed at (1) replicating and offering more insight in the initial impression formation effects (Experiment 1-3) and (2) providing evidence that signals of dominance and submissiveness affect participants’ anticipation performance within a simulated soccer penalty task (Experiment 3). We report three experiments demonstrating that participants form more positive impressions and have less confidence in saving penalty kicks from dominant penalty-takers (or scoring against dominant goalkeepers, Experiment 1) than submissive penalty-takers (goalkeepers). However, we did not find evidence that participants’ automatic associations with dominant and submissive players underlie these findings (Experiment 2). Finally, we demonstrate that anticipation of kick direction is influenced by penalty-takers’ body language (Experiment 3). Participants performed worse in the simulated soccer penalty task against dominant than submissive penalty-takers. No mediation of impression formation was found. 相似文献
276.
健康领域的跨期决策关系着个体和国民的健康和福祉。目前学界对该领域的研究主要停留在参考传统金钱领域的相关理论模型和方法的阶段, 但健康跨期决策具有领域特异性, 沿袭金钱领域理论模型和方法, 导致该领域在研究方法和结果上存在较大的不一致性。健康跨期决策的行为后果是该领域关注重点, 多数研究均报告个体的低时间折扣率、高未来时间取向与其健康保护行为正相关, 与健康风险行为呈负相关。该领域也关注健康跨期决策的影响机制, 如决策对象和决策主体的核心特征等因素。未来研究亟需发展适用于健康领域的跨期决策模型和研究范式, 明确健康行为与跨期决策偏好的关系, 深入探讨健康跨期决策的内在选择机制, 并在健康行为干预和医疗卫生政策应用方面进行更多的尝试和探索。 相似文献
277.
在干预国民健康饮食行为方面, 更“隐性”的助推策略因其针对直觉思维系统发挥作用, 比传统的干预政策更具优势。基于助推策略对食物选择决策影响机制的不同, 健康饮食助推策略可构建为提供决策信息、改善决策选项、影响决策结构和提醒决策方向4个大类及9个小类的框架体系。助推策略在实践中仍存在争议, 因而在中国实施时需与传统政策结合使用, 充分考虑中国国情和消费群体特征, 并充分利用信息技术和大数据优势, 助力健康中国。 相似文献
278.
慈悲冥想是一类旨在培养对自己和他人无条件的善意与同情的冥想练习方法, 主要包括慈心禅和怜悯禅修。诸多研究表明, 慈悲冥想可以促进练习者的利他行为。就影响机制而言, 慈悲冥想可能是通过增强对他人不幸的共情反应, 促进情绪的有效调控和提高亲社会动机来影响练习者的利他行为。未来的研究需选择更具生态效度的利他行为测量方法, 深入挖掘慈悲冥想影响利他行为的动态神经加工过程, 并尝试将慈悲冥想应用于临床群体。 相似文献
279.
280.
本研究旨在探讨拥有生命意义与亲社会行为的相互关系。研究1对我国10省15所高校2375名学生的拥有生命意义、亲社会行为进行横断面调查。研究2对四川某高校878名学生的拥有生命意义和亲社会行为进行间隔三个月和六个月的三次追踪测量。结果发现:大学生拥有生命意义与亲社会行为具有相互促进的关系,拥有生命意义能稳定正向预测亲社会行为,亲社会行为也能够在一定程度上促进拥有生命意义,但这种促进作用不够稳定;拥有生命意义对利他的、情绪的、匿名的、依从的、紧急的亲社会行为有显著正向影响;而只有利他的亲社会行为能显著预测拥有生命意义。 相似文献