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81.
Appropriate communication between road users can lead to safe and efficient interactions in mixed traffic. Understanding how road users communicate can support the development of effective communication methods for automated vehicles. We carried out observations of 66 pedestrian-driver and 124 driver-driver interactions in a shared space setting. Specific actions and reactions of the road users involved were recorded using a novel observation protocol. Overall, results showed that pedestrians’ failure to look towards a driver created the greatest uncertainty in the interaction, with the driver slowing down, but not completely stopping, in response to pedestrians. Looking towards the driver also influenced which road user took priority in driver-driver interactions. Groups of pedestrians were more likely to be given priority than an individual pedestrian, and the use of vehicle-based signals were also associated with taking priority during an interaction. Our observations show the importance of non-verbal communication during road user interactions, highlighting it as an essential area of research in the development of automated vehicles, to allow their safe, cooperative, interactions with other road users. Observations were made on a limited number of interactions to inform challenges facing future automated vehicles. Further work should therefore be done to corroborate and extend our findings, to examine interactions between human road users and automated vehicles in shared space settings. 相似文献
82.
Driver distraction is a major cause of road crashes and has a great influence on road safety. In vehicles, one of the common distracting sources is navigation systems (NSs). The navigation system (NS) can distract the driver due to following directions and reading the provided information through its display. These tasks take the driver’s attention from the primary task of driving and may cause poor driving performance, increasing the risk of crashes. In this paper, the effect of the environment (i.e., urban areas and rural areas), the navigation system display (NSD) size, environmental illumination, and gender on young drivers between the ages of 18 and 29 years mental workload was investigated using a simulated driving experiment. To evaluate each driving condition, the NASA-TLX (NASA Task Load Index) workload assessment tool, and a distraction evaluation element, were introduced and used to assess the overall workload, the workload subscales and the distraction by the NSD. The assessment showed a higher perceived overall workload for urban areas and night driving as compared to a rural areas and daytime driving. Moreover, the results showed a greater perceived distraction by the NSD in urban areas compared to driving in rural areas. The subjects also felt distracted when using the small NS compared to using the large NS. The study concluded that urban areas driving, and night driving creates higher perceived workload than rural areas and daytime driving. Furthermore, small NSD leads to more perceived distraction than large NSD while driving. The NSD designers may utilize this research findings to optimize NSD designs to improve driving safety, performance and comfort. Moreover, this study contributes to our understanding of the effect of the NSD size on driving workload and distraction. 相似文献
83.
This study was designed to evaluate the short- and long-term effects of speed display signs on driving speed at pedestrian crossings in a low-speed (40 km/h) urban environment. Driving speeds were compared 1 week before installation, after installation (1 week; 1 month; 3 months; 5 months) and 1 week after removal. The main results showed that the speed displays decreased the mean speed by 0.5–2.9 km/h, which translates to a 4–22% drop in pedestrian fatality risk. Furthermore, there was a drop in the proportion of speeding vehicles and approaching speed of individual vehicles. The decrease in speed persisted over time, suggesting that speed displays may reduce speeds in the long term. In conclusion, installing speed displays at pedestrian crossings on collector streets reduces driving speeds and could contribute to the safety of pedestrians. 相似文献
84.
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
85.
Route familiarity affects a driver’s mental state and indirectly affects traffic safety; however, this important factor is easily overlooked. Previous research on route familiarity has only analysed psychological states in terms of unfamiliarity and familiarity, the influence of driving behaviour and driving environment on psychological states has been ignored. As a result, the mechanisms through which the route familiarity influence driver psychological states, and vice versa, are unclear. This study proposes a quantitative framework for studying driver psychological condition and route familiarity using experimental data from a real driving task and driving environment data. The experimental data included 1022 observations obtained by 23 participants over 7 consecutive trials on 6 unfamiliar experimental routes with large differences in scenarios; environmental data were automatically extracted after segmenting a driving video through the Dilated Residual NetWorks model. The results reveal that (1) the relationship between the driver’s psychological condition and route familiarity is not monotonic and is different for straight and turning sections; (2) the driver’s psychological condition is influenced by the visual scene elements and the type of road section, and the results of the multivariate regression analysis quantified the variability of the influence; and (3) unlike a majority of findings on distracted driving, our study suggest that the driver’s attention to the external environment in the urban distracted driving state will gradually approach a ‘distraction threshold’, and the time and size of the ‘distraction threshold’ are influenced by the driver. This study can further the development of urban traffic safety research and help urban designers plan and improve urban landscapes to ensure drivers maintain stable mental states when they drive. 相似文献
86.
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
87.
为探讨创伤后应激障碍(PTSD)及其各个症状簇对震后青少年自杀意念的影响,并检验安全感在其中的调节作用,研究采用创伤暴露程度问卷、流调中心抑郁量表儿童版、DSM-5的PTSD症状核查表、安全感量表和儿童行为问题核查表对汶川地震8.5年后的1136名中学生进行调查。结果发现:PTSD、负性认知和情绪改变症状、警觉性增高症状分别正向预测自杀意念,侵入性症状和回避性症状对自杀意念的预测作用不显著;安全感在侵入性症状、负性认知和情绪改变症状、警觉性增高症状、PTSD与自杀意念之间起负向调节作用,在回避性症状与自杀意念之间不起调节作用。这表明PTSD各症状簇对震后青少年自杀意念的预测作用不同,且安全感在其中发挥的调节作用也不同。 相似文献
88.
Embry DD 《Clinical child and family psychology review》2002,5(4):273-297
A behavioral vaccine provides an inoculation against morbidity or mortality, impacting physical, mental, or behavior disorders. An historical example of a behavioral vaccine is antiseptic hand washing to reduce childbed fever. In current society, issues with high levels of morbidity, such as substance abuse, delinquency, youth violence, and other behavioral disorders (multiproblems), cry out for a low-cost, widespread strategy as simple as antiseptic hand washing. Congruent research findings from longitudinal studies, twin studies, and other investigations suggest that a possibility might exist for a behavioral vaccine for multiproblem behavior. A simple behavioral strategy called the Good Behavior Game (GBG), which reinforces inhibition in a group context of elementary school, has substantial previous research to consider its use as a behavioral vaccine. The GBG is not a curriculum but rather a simple behavioral procedure from applied behavior analysis. Approximately 20 independent replications of the GBG across different grade levels, different types of students, different settings, and some with long-term follow-up show strong, consistent impact on impulsive, disruptive behaviors of children and teens as well as reductions in substance use or serious antisocial behaviors. The GBG, named as a best practice for the prevention of substance abuse or violent behavior by a number of federal agencies, is unique because it is the only practice implemented by individual teachers that is documented to have long-term effects. Presently, the GBG is only used in a small number of settings. However, near universal use of the GBG, in major political jurisdictions during the elementary years, could substantially reduce the incidence of substance use, antisocial behavior, and other adverse developmental or social consequences at a very modest cost, with very positive cost-effectiveness ratios. 相似文献
89.
Xenotransplantation, or the use of animal cells, tissues and organs for humans, has been promoted as an important solution
to the worldwide shortage of organs. While scientific studies continue to be done to address problems of rejection and the
possibility of animal-to-human virus transfer, socio-ethical and legal questions have also been raised around informed consent,
life-long monitoring, animal welfare and animal rights, and appropriate regulatory practices. Many calls have also been made
to consult publics before policy decisions are made. This paper describes the Canadian public consultation process on xenotransplantation
carried out by the Canadian Public Health Association in an arm’s length process from Health Canada, the ministry overseeing
government health policy and regulation. Focusing on six citizen fora conducted around the country patterned after the citizen
jury deliberative approach, the paper describes the citizen panelists’ recommendations to hold off on proceeding with clinical
trials and the rationales behind this recommendation. The consultation process is discussed in the context of constructive
technology assessment, a framework which argues for broader input into earlier stages of technology innovation, particularly
at the technology design stage.
This study was supported by a grant to the first author from the Social Sciences and Humanities Research Council in Canada. 相似文献
90.
Noddings N 《Theoretical medicine and bioethics》2002,23(6):441-454
Care theory offers a way to overcome a weaknessof liberalism – its reluctance to intervene inthe private lives of adults. In caring for thehomeless, we must sometimes use a limited formof coercion, but our intervention is alwaysinteractive, and the process of finding asolution is one of negotiation between theneeds expressed by the homeless and the needswe infer for them. 相似文献