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521.
This study investigated the manner in which the driving performance of young people was affected by a collision warning system when they encountered a driver running a red light at an intersection. Furthermore, the causal relationship among driving performance, traffic factors and intersection accidents was examined using Path Analysis. Participants drove a driving simulator with an intersection collision warning system (ICWS) in a simulated urban area. The driving performance measures recorded were reaction time, speed, lateral position deviation and crash events. Experimental results indicated that drivers who drove a vehicle with an ICWS audio signal at an intersection had a shorter reaction time, a lower speed and a reduced accident rate than those observed while driving a vehicle without ICWS audio signal. Furthermore, Path Analysis showed that the ICWS had an indirect effect on accident rate reduction through improved driving performance. The location of intersection accident had both direct and indirect effects on the accident rate. The number of driving days per week had a direct effect on accident rate reduction.  相似文献   
522.
523.
Hens responded under multiple fixed‐ratio schedules with equal response requirements and either a 1‐s or a 6‐s reinforcer. Upcoming reinforcer size was indicated by key color. Components were presented in a quasirandom series so that all four component transitions occurred. Postreinforcement pauses were affected by the upcoming and preceding reinforcer size, with longer pauses after large reinforcers followed by small reinforcers than when followed by large ones, and longer pauses after small reinforcers that were followed by small reinforcers rather than large ones. Pauses increased with fixed‐ratio size and the effects of reinforcer size were larger the larger the ratio. When reinforcer size was not signaled—mixed fixed‐ratio schedules—pauses were shorter after small than after large reinforcers. Signalling the upcoming reinforcer attenuated the effect of the previous reinforcer size on pause duration when small was followed by small and when either small or large by large, but enhanced the effect when large was followed by small. There was no effect of reinforcer size on pause duration when single fixed‐ratio schedules were arranged. The effects of reinforcer size on pauses depends on the size and range of the fixed ratios as well as the exact procedures used in the study.  相似文献   
524.
We tested whether a mirror could enhance the efficacy of a self-compassion manipulation in increasing soothing positive affect and heart rate variability (HRV). Eighty-six participants generated four phrases they would use to soothe and encourage their best friend. Second, they described an episode where they criticized themselves and were assigned to one of three conditions: (a) repeat the four phrases to themselves while looking at the mirror; (b) repeat the four phrases to themselves without the mirror; (c) look at themselves in the mirror without repeating the phrases. Participants in condition (a) reported higher levels of ‘soothing’ positive affect and HRV compared to participants in conditions (b) and (c). The effect of the ‘phrases at the mirror’ manipulation on soothing affect was mediated by increased common humanity. The mirror enhances the efficacy of this self-compassion manipulation in activating the soothing affect system connected with parasympathetic nervous system activity.  相似文献   
525.
The current study investigated high‐frequency heart rate variability (HF‐HRV) as a potential mediator between childhood parental warmth and later health and mortality outcomes. Participants were 1,255 adults (56.9% female). Childhood parental warmth was reported retrospectively at mean age 46; resting HF‐HRV was measured at mean age 57; cardiovascular health and self‐evaluated health were assessed at mean ages 57 and 63, and mortality records extracted at mean age 63. Results revealed a positive association between childhood parental warmth and resting HF‐HRV, as well as associations between higher HF‐HRV and reduced risk of having a later cardiovascular health problem and of mortality by age 63. Mediation analyses revealed a small significant indirect effect of parental warmth, through HF‐HRV, on cardiovascular health.  相似文献   
526.
The current research set out to measure the moderating effect that urban design may have on bicyclist physiology while in transition. Focusing on the hilly City of Wuppertal, Germany, we harnessed bicyclists with mobile sensors to measure their responses to urban design metrics obtained from space syntax, while also adjusting for known traffic, terrain, and contextual factors. The empirical strategy consisted of exploratory data analysis (EDA), ordinary least squares (OLS), and a local regression model to account for spatial autocorrelation. The latter model was robust (R2 = 68%), and showed that two statistically significant (p < 0.05) urban design factors influenced bicyclist physiology. Controllability, a measure of how spatially dominated a space is, increased bicyclist responses (i.e., decreased comfortability); while integration, which is related to accessibility and connectivity, had the opposite effect. Other noteworthy covariates included one-way streets and density of parked automobiles: these exerted a negative influence on bicyclist physiology. The results of this research ultimately showed that nuanced urban designs have a moderate influence on bicycling comfort. These outcomes could be utilized by practitioners focused on implementing appropriate interventions to increase bicyclist comfort levels and this mode share.  相似文献   
527.
本文将多维题组反应模型(MTRM)应用到多维题组测验的项目功能差异(DIF)检验中,通过模拟研究和应用研究探究MTRM在DIF检验中的准确性、有效性和影响因素,并与忽略题组效应的多维随机系数多项Logistic模型(MRCMLM)进行对比。结果表明:(1)随着样本量的增大,MTRM对有效DIF值检出率增高,错误率降低,在不同条件下结果的稳定性更高;(2)与MRCMLM相比,基于MTRM的DIF检验模型检验率更高,受到其他因素的影响更小;(3)当测验中题组效应较小时,MTRM与MRCMLM结果差异较小,但是MTRM模型拟合度更高。  相似文献   
528.
研究发现,人们普遍具有追求公平的偏好,即人们在追求个人收益时也会关注收益分配的公平性。随着电生理技术的发展,越来越多的研究者采用电生理技术对公平偏好进行深入探讨。本研究从脑电、皮肤电、心电等方面梳理公平偏好的电生理机制。脑电的研究发现,公平偏好相关的脑电主要涉及反馈相关负波和P300;皮肤电的研究发现,相比于公平分配,个体在不公平分配情况下其皮肤电的激活水平更高;心率的研究发现,相比于公平分配,个体遭遇不公平分配时其心率降低。研究公平偏好电生理机制有助于更深入地揭示公平偏好的产生根源与形成过程。未来可从公平偏好电生理的整合研究、公平偏好的脑成像与电生理的整合性探索,以及拓展公平偏好电生理的外部效度和研究范式等方面展开进一步探究。  相似文献   
529.
When given a choice between two alternatives, each offering food after the same delay with different but signaled probabilities, pigeons often prefer the low probability alternative. This preference is surprising because pigeons fail to maximize the rate of food intake; they exhibit a suboptimal preference. We advance a new explanation, the Δ–∑ hypothesis, in which the difference in probability of reinforcement within terminal links (Δ) and the overall reinforcement probability rate of each alternative (∑) are the key variables responsible for such suboptimal preference. We tested the Δ–∑ hypothesis in two experiments. In Experiment 1, we manipulated the Δs while maintaining constant all other parameters of the task, in particular the ∑s. We predicted a preference for the alternative with the larger Δ. In Experiment 2, we examined the effect of the overall reinforcement probabilities, the ∑s, while maintaining constant all other parameters of the task, in particular the Δs. We predicted a preference for the larger ∑. The results of both experiments support the Δ–∑ hypothesis.  相似文献   
530.
本研究探讨心率变异性(HRV)特征在高水平应激条件下对神经质水平的区分力。研究选取200名被试以大五人格量表测量情绪稳定性,实施了应激诱发实验,利用光体积扫描传感器采集被试者HRV指标;利用LASSO回归分析筛选参数构建对神经质的预测模型。结果显示:模型的预测数据与神经质得分高低显著正相关;不同阶段内预测数据与神经质得分显著正相关;两两比较中实验条件阶段与其他阶段预测值差异显著。研究表明,在高应激条件下,HRV是人格神经质较好的预测指标。  相似文献   
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