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11.
红光照明条件下VDT不同显示色的视觉效果比较 总被引:1,自引:1,他引:1
本研究以VDT上持续进行的视觉作业速度和眼的调节辐合时间作为指标,对红光照明条件下VDT显示的红、黄、绿、蓝、白五种字符色的视觉效果进行了比较.实验中,VDT背景光的主波长为630nm.结果表明,五种字符色在两项指标上均表现出显著差异;绿色显示的视觉效果最好,红色显示的效果最差,黄、白、蓝三色处于中间. 相似文献
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去工业化与人民公社的困境 总被引:1,自引:1,他引:0
人民公社承载着组织农村工业化之重任,普遍试办社队工业企业、就地转移劳动力、使农民尽快富裕起来是人民公社工农商学兵、农林牧副渔综合发展的题中之意.然而1962的政策大调整将其去工业化之后,人民公社被归结为一种纯农组织而失去了它应有的功能,并由此开始陷入困境而走向终结. 相似文献
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Yiqun Wu;Jingyi Xu;Yishan Shen;Yijie Wang;Yao Zheng; 《Journal of personality》2024,92(5):1299-1314
Having higher levels of mainstream cultural orientation (MCO), an important component of acculturation attitudes and behaviors, is beneficial for ethnic/racial minority students during the transitions into university. Scant research has investigated MCO at a micro daily timescale. This study examined how personality (agreeableness) functions in conjunction with interpersonal processes (inter-ethnic contact and perceived discrimination) to influence MCO as daily within-person processes. 相似文献
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Haochen Xu Guanhua Fang Zhiliang Ying 《The British journal of mathematical and statistical psychology》2020,73(3):474-505
We propose a latent topic model with a Markov transition for process data, which consists of time-stamped events recorded in a log file. Such data are becoming more widely available in computer-based educational assessment with complex problem-solving items. The proposed model can be viewed as an extension of the hierarchical Bayesian topic model with a hidden Markov structure to accommodate the underlying evolution of an examinee's latent state. Using topic transition probabilities along with response times enables us to capture examinees' learning trajectories, making clustering/classification more efficient. A forward-backward variational expectation-maximization (FB-VEM) algorithm is developed to tackle the challenging computational problem. Useful theoretical properties are established under certain asymptotic regimes. The proposed method is applied to a complex problem-solving item in the 2012 version of the Programme for International Student Assessment (PISA). 相似文献
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心理物理试验是研究立体视觉的主要方法。70年代VEP开始用于体视研究,并取得许多结果。由于VEP信号复杂,这些结果不能令人满意。本文使用心理物理试验和VEP对比方法对体视加以研究。我们的结果是:VEP波形中第一个正峰与刺激图形的亮度有关;N_2峰和P_3峰的潜伏期对判断体视存在与否有重要价值;本试验确定N_2峰潜伏期在体视存在时约为240ms—280ms,无体视存在时约为290ms—310ms;P_3峰潜伏期在体视存在时约为280ms—310ms,无体视存在时约为340ms—360ms;体视存在时的VEP与无体视存在时的VEP的互相关系数小于0.1;有体视的VEP其功率谱密度在8Hz附近有一峰;心理物理试验中使用强制选择得到的结果从VEP波形比较中可以确认是可靠的;有体视的VEP其N_2和P_3的潜伏期随视差变化呈现规律性改变。 相似文献
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Cross-correlation and most other longitudinal analyses assume that the association between 2 variables is stationary. Thus, a sample of occasions of measurement is expected to be representative of the association between variables regardless of the time of onset or number of occasions in the sample. The authors propose a method to analyze the association between 2 variables when the assumption of stationarity may not be warranted. The method results in estimates of both the strength of peak association and the time lag when the peak association occurred for a range of starting values of elapsed time from the beginning of an experiment. 相似文献
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Two experiments with the Stroop paradigm were conducted to investigate the role of phonological codes in access to the meaning of Chinese characters. Subjects named the ink color of viewed characters or color patches. Key items were color characters, their homophones with the same tone, homophones with different tones, and semantic associates. Apart from finding the usual Stroop interference effect, homophones produced significant interference in the incongruent condition, provided that they had the same tone as the color characters. The interference effect from homophones, however, was significantly smaller than that from color characters. Semantic associates generated an interference effect in the incongruent condition, an effect of the same magnitude as the effect from the same-tone homophones. Finally, in the congruent conditions, all the key items yielded facilitations compared to neutral controls, though the facilitation from color characters was larger than the facilitations from other types of characters. These findings suggest that phonological codes in Chinese are activated obligatorily and provide early sources of constraint in access to meaning. 相似文献