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51.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces.  相似文献   
52.
主观幸福感回溯式自陈报告测量存在一定的不足,在此基础上研究者们发展了关注时间因素的即时测量方法,如经验取样法(ESM),生态瞬时评定法(EMA),日重现法(DRM),U指数(The U-Index)等.从传统测量走向多样化测量大大提高了主观幸福感测量的生态效度,同时也为国民幸福指数的构建与评估提供了一定参考.  相似文献   
53.
The present study is a cross-sectional survey that investigates ethical practices among Chinese psychotherapists from the perspective of a large representative sample of Chinese clients (N?=?1,100). In reports from clients, we found that psychotherapists did poorly in providing informed consent and had other ethical difficulties in the therapeutic setting and with dual relationships. We conclude that Chinese culture, especially Confucianism, had significant impact on the attitudes toward the psychotherapists' ethical practices, which complicated ethical dilemmas. It is important for cross-cultural psychotherapists to become sensitive to the influences of traditional Chinese culture when counseling Chinese clients.  相似文献   
54.
Auditory distractions can have serious consequences in critical situations such as driving. Mobile phones, radios, media players, and information devices that interpret and produce speech are increasingly common in vehicles, but the threats to visual attention are not yet fully understood. In three experiments, we found that most speech tasks had relatively small adverse effects on the detection of a briefly presented target among distractors across a 60° subarea of the visual field. Although there was a little impact on detectability, moderately difficult speech tasks slowed responding relative to silence. Our most demanding condition—generating and speaking a word beginning with the last letter of another word—had the greatest effects on accuracy and latency, with responding slowed by about 900 ms. An impairment of this magnitude presents a significant threat to safe driving and calls into question the belief that hands‐free voice‐controlled devices are the answer to the problem of driver distraction. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
55.
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component.  相似文献   
56.
Eye-tracking technique and visual search task were employed to examine the cognitive advantage for one’s own name and the possible effect of familiarity on this advantage. The results showed that fewer saccades and an earlier start time of first fixations on the target were associated with trials in which participants were asked to search for their own name, as compared to search for personally familiar or famous names. In addition, the results also demonstrated faster response times and higher accuracy in the former kind of trials. Taken together, these findings provide important evidence that one’s own name has the potential to capture attention and that familiarity cannot account for this advantage.  相似文献   
57.
We examined the effects of cue luminance on visual orienting. Experiment 1 established that the commonly-found early facilitation and late inhibition of return (IOR) effects were independent of cue luminance with single cues in terms of their amplitude, although IOR was delayed in the low compared to the high luminance cue condition. In contrast, Experiment 2 revealed that, with dual cues of mixed luminance, both facilitation and IOR effects were found only with bright cues. When cues had equal luminance, however, there were cueing effects for two cued locations but only when the cues were bright. The data were accommodated in a neural network model of biased competition in which cueing effects emerge at more than one location provided input activation is sufficient to overcome competitive damping of the selection system.  相似文献   
58.
Jeffrey (1983) proposed a generalisation of conditioning as a means of updating probability distributions when new evidence drives no event to certainty. His rule requires the stability of certain conditional probabilities through time. We tested this assumption (“invariance”) from the psychological point of view. In Experiment 1 participants offered probability estimates for events in Jeffrey's candlelight example. Two further scenarios were investigated in Experiment 2, one in which invariance seems justified, the other in which it does not. Results were in rough conformity to Jeffrey's (1983) principle.  相似文献   
59.
为考察学龄儿童心理理论与情景记忆的关系,111名小学4-6年级儿童在两周内完成了心理理论(包括二级错误信念、失言和白谎等)和情景记忆(回忆过去"一个星期内"、"一个月内"和"一年内"亲历的具体事件;以及想象将来"一个星期内"、"一个月内"和"一年内"可能发生在自己身上的具体事件)等任务。控制了年龄效应后,线性回归分析发现儿童回忆过去时"谈及他人"、想象将来时"谈及自我"和"谈及他人"与心理理论的认知成分存在显著关联。而儿童回忆过去时"谈及他人"与心理理论的情感成分有显著关联。结果表明,学龄儿童心理理论可以分为认知成分和情感成分,情景记忆与心理理论不同成分的关系存在差异。  相似文献   
60.
This article applies a two-process “neural autopilot” model to field data. The autopilot model hypothesizes that habitual choice occurs when the reward from a behavior has low numerical “doubt” (i.e., reward prediction errors are small). The model toggles between repeating a previous choice (habit) when doubt is low and making a goal-directed choice when doubt is high. The model has ingredients established in animal learning and cognitive neuroscience and is simple enough to make nonobvious predictions. In two empirical applications, we fit the model to field data on purchases of canned tuna and posting on the Chinese social media site Weibo. This style of modeling is called “structural” because there is a theoretical model of how different variables influence choices by agents (the “structure”), which tightly restricts how hidden variables lead to observed choices. There is empirical support for the model, more strongly for tuna purchases than for Weibo posting, relative to a baseline “reduced-form” model in which current choices are correlated with past choices without a mechanistic (structural) explanation. An interesting set of predictions can also be derived about how consumers react to different kinds of changes in prices and qualities of goods (this is called “counterfactual analysis”).  相似文献   
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