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91.
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
92.
“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
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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
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根据血压昼夜节律,观察给药时间对血压晨峰的影响。256例原发性高血压患者,经24h动态血压监测分为超杓型(n=49)、杓型(n=127)和非杓型(n=80)3组;各组再分为清晨服药组和晚上服药组。用药6周,比较用药前后血压昼夜节律及血压晨峰的变化,发现在改变血压昼夜节律及降低血压晨峰方面,超杓型组清晨服药优于晚上服药,非杓型组晚上服药优于清晨服药;杓型组清晨服药与晚上服药均能降低晨峰值,提示根据个体血压昼夜节律选择服药时间能更好地控制血压晨峰。 相似文献
97.
Consumers often share word of mouth, and such interpersonal communication shapes attitudes and purchases. But while some research has examined what consumers talk about, there has been less attention to when consumers discuss. How does the distance from now (i.e., whether something is temporally near or far away) shape the likelihood of discussion? And might the effect of temporal distance on word of mouth vary based on whether those things happened in the past or will happen in the future? Five studies, including analyses of thousands of social media posts, address these questions. They suggest that consumers tend to talk about temporally near things, but that this is moderated by whether they are talking about the past or future (i.e., consumers talk about more temporally distant things when talking about the future). Accessibility seems to play an important role in these effects. While temporally near things tend to be more accessible, on average, goals and plans are more likely to remain active in the future, which shapes what gets discussed. These findings have implications for understanding drivers of word of mouth, how time shapes consumer behavior, and how companies can more effectively manage interpersonal communication. 相似文献
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Gray VA 《Journal of the experimental analysis of behavior》1976,25(2):199-207
Five pigeons were given single-stimulus training on an 8-sec differential-reinforcement-of-low-rate schedule followed by steady-state generalization training using 12 wavelength stimuli. Three birds had a high percentage of reinforced responses on the training schedule and flat generalization gradients of total responses. The birds with fewer reinforced responses had much steeper generalization gradients. Generalization gradients plotted as a function of both stimulus wavelength and interresponse time showed that for most birds, stimulus control was restricted to responses with long interresponse times. Responses with very short interresponse times were not under stimulus control and there was some evidence of inhibitory control of short interresponse times. Interresponse-times-per-opportunity functions, plotted as a function of stimulus wavelength, showed that stimulus wavelength controlled the temporal distribution of responses, rather than the overall rate of response. The data indicate that the differential-reinforcement-of-low-rate schedule generates several response categories that are controlled in different ways by wavelength and time-correlated stimuli, and that averaging responses regardless of interresponse-time length obscures this control. 相似文献
100.