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151.
Vehicles equipped with connected vehicle technologies are able to communicate with each other and with infrastructures. Compared to Advanced Driving Assistance Systems (ADAS) using camera systems and sensor technologies, the Connected Vehicle Systems (CVS) leverage the wireless communication networks to detect hazards with a greater range, alert drivers of hazards much earlier, and therefore enhance driving safety. However, drivers’ reliance on the CVS to detect critical situations could negatively affect them maintaining situation awareness (SA) in noncritical situations when no warning is issued by the CVS. The present study conducted a driving simulator experiment with 40 participants to investigate the effect of connected vehicle systems on driver SA in normal, noncritical driving scenarios after they were exposed to the CVS with different designs of collision warning lead time (3 s, 6 s, and no warnings). After drivers experienced the CVS-supported warnings with the assigned design of lead time in critical situations, driver SA was measured in normal driving conditions using the freeze probe technique. Results revealed that drivers who experienced the CVS with early warnings (6 s) showed lower SA for normal driving events compared to those who experienced the CVS with late warnings (3 s) or no warnings. Although early warnings of CVS brought more safety benefits to drivers in critical situations, the degraded driver SA due to drivers’ reliance on such warning systems could endanger drivers when a system failure occurred. These findings highlight the importance of balancing the effects of warning lead time on driver SA and driving performance in designing connected vehicle systems.  相似文献   
152.
“时间”是跨期决策的“必需品”, 人们感知到的延迟时间决定跨期决策的结果。近年来, 研究者发现“时间长度感知”、“时间资源感知”和“时间框架感知”是时间感知作用于跨期决策的主要方式。时间感知的神经作用机制包含微观层面和宏观层面两种。“对数/指数时间折扣模型”、“感知时间基础模型”及“多模态漂移扩散模型”解释了时间感知的作用方式。然而, 现有理论模型还存在诸多局限, 主要包括“长短时距预测偏差”和“实际决策与预期决策偏差”两个方面。因此, 深入探讨时间感知影响跨期决策的基本方式, 分析现有理论模型的局限性并提出整合的机制框架具有十分重要的意义。未来研究亟需进一步整合时间感知的理论模型, 开展脑机制与应用方面的研究, 从深层揭露时间感知的作用本质, 帮助个人与社会更理性地决策。  相似文献   
153.
采用青少年时间态度量表、成就动机量表和学业拖延问卷,对 733名中学生进行调查,旨在探究时间态度与学业拖延的关系,揭示成就动机在时间态度与学业拖延之间的中介作用机制。结果发现(1)过去消极、现在消极和未来消极与学业拖延呈显著正相关,过去积极、现在积极和未来积极与学业拖延呈显著负相关。(2)过去消极、现在消极和未来消极与成就动机呈显著负相关,过去积极、现在积极和未来积极与成就动机呈显著正相关;成就动机与学业拖延呈显著负相关。(3)成就动机在现在消极与学业拖延之间起部分中介作用,在未来积极、未来消极与学业拖延之间起完全中介作用。  相似文献   
154.
本研究旨在归纳中文里可以用于测量解释偏差的多义词,并使用多义词造句任务,在广泛性焦虑症状人群中评估其测量有效性。经过对多义词负性与非负性含义常用程度的评分以及多义词造句任务项目区分度、信度、效度和目的隐蔽性的检验,筛选出两含义常用程度大致相同且对焦虑较为敏感的34个题目构成多义词造句任务,该任务信度良好,可以有效测得高低广泛性焦虑和状态焦虑人群中解释偏差的显著差异,且与同类的乱句重排任务相比,能猜出与猜对实验目的的被试显著更少。因此,中文多义词造句任务信效度良好,具有便捷、隐蔽的优势,可以用于解释偏差的相关研究。  相似文献   
155.
研究以分子结构式为材料,让被试在单任务或双任务条件下以集中呈现和交错呈现的方式进行学习,并通过操作广度、旋转广度和对称广度任务测量工作记忆容量(working memory capacity, WMC),探究在基于规则类别学习中交错呈现优势的稳定性。结果显示,交错呈现优势仅体现在文科生中;而对于理科生,集中呈现效果较佳。另外,任务数量和WMC均不影响交错呈现优势,表明交错呈现优势稳定存在于单任务和双任务条件中,且不同WMC的个体均能从交错学习获益。  相似文献   
156.
为探讨挫折情境下自我肯定对执行功能的影响,创设挫折和非挫折情境,采用价值观自我肯定干预,通过Stroop范式和2-back范式分别测量抑制控制和工作记忆的刷新能力。结果发现,挫折情境下的Stroop任务和2-back任务反应时均高于非挫折情境;挫折情境下自我肯定组在Stroop任务和2-back任务上的反应时均显著低于非自我肯定组,而非挫折情境下两组的反应时没有显著性差异;Stroop效应量在情境与肯定条件上的交互作用不显著。结果表明挫折降低了执行功能的任务表现,自我肯定干预能够改善挫折情境下执行功能相关的任务成绩,促进了个体对工作记忆任务的刷新能力和Stroop任务的认知表现,但对抑制控制能力的改善没有明显作用。  相似文献   
157.
158.
159.
ABSTRACT. We explored the utility of analyzing within- and between-balloon response patterns on a balloon analogue task (BAT) in relation to overall risk scores, and to a choice between a small guaranteed cash reward and an uncertain reward of the same expected value. Young adults (n = 61) played a BAT, and then were offered a choice between $5 in cash and betting to win $0 to $15. Between groups, pumping was differentially influenced by explosions and by the number of successive unexploded balloons, with risk takers responding increasingly on successive balloons after an explosion. Within-balloons, risk takers showed a characteristic pattern of constant high rate, while non-risk takers showed a characteristic variable lower rate. Overall, results show that the higher number of pumps and explosions that characterize risk takers at a molar level, result from particular forms of adaptation to the positive and negative outcomes of choices seen at a molecular level.

Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/vgen.  相似文献   

160.

Objective

To describe an immobility reaction (IR) that was not previously reported at or immediately after birth in human newborns.

Method

We analyzed 31 videos of normal term vaginal deliveries recorded from Time 0 of birth defined as the as the moment that lies between the birth of the thorax and the pelvis of the infant. We searched for perinatal factors associated with newborn's IR.

Results

IR at birth was observed in 8 of the 31 newborns. The main features of their behavior were immobilization, frozen face, shallow breathing and bradycardia. One of the 8 newborns had sudden collapse 2 h after birth. We found significant relationships between maternal prenatal stress (PS) and IR (p = .037), and a close to significant one between infants’ lividness at Time 0 and IR (p = .053). The first breath of the 31 newborns occurred before and was not associated with the first cry (p < .001).

Discussion

The main features of IR at birth are similar to those of the universal most severe response to severe stress or danger. The relationship with PS suggests that children who had IR at birth might be at risk for similar disorders as those associated with PS. Sudden neonatal collapse of one of the IR newborns needs further research to determine if they are at risk for sudden infant death syndrome.

Conclusion

This first report of an IR reaction at birth in human infants could open up new paths for improving early neonatal care. Further research is needed for maternal PS, stress hormones, umbilical cord blood pH measurements in IR newborns. The challenge of education and support for parents of IR newborns is outlined.  相似文献   
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