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用微机化的伪随机点立体图对发生器产生静态和动态随机点立体图对(RDS),显示在左右两个示波器上。RDS图形中的元素密度可以改变。具有正常立体视的10名被试通过立体镜观察这些图形,测量双眼融合能产生完整立体图形感知所需最小的元素密度,即密度容限。 设计了三个实验用以检测改变RDS图形的空间参数对密度客限的影响。第一个实验,在静、动态RDS图形下,改变视差图形面积;第二个实验,改变视差图形的形状;第三个实验,改变视差图形的周长。 实验结果表明,双眼深度感知要求一定的元素密度容限,视差图形的大小和形状对密度容限有一定程度的影响。静态和动态RDS图形的密度容限也不相同。 本文利用RDS的整体立体感知特性和空间频率通道理论对实验结果进行了讨论。 相似文献
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This article introduces a simple survey method to distinguish between two types of variables that affect happiness—type A, which exerts an absolute effect on happiness, and type B, which affects happiness only through social context. The authors validate the method by comparing its findings with the findings of a theoretically superior but less practical experimental method, and use the method to identify the AB nature of a variety of naturally-occurring variables among both college students and people with work experience. We conclude by discussing the limitation of this method as well as its potential to inform policymakers about where to invest resources in order to improve people’s happiness over time. 相似文献
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Research has documented that children and adolescents with attention-deficit/hyperactivity disorder (ADHD) are at increased
risk of substance use problems. Few studies, however, have focused on early-onset substance use. This study therefore investigated
how the two symptom dimensions of ADHD (hyperactivity/impulsivity and inattention) are associated with early-onset substance
use, the role of persistent ADHD for the association, and to what extent the association is influenced by genetic and environmental
factors. Twins (1,480 pairs) in the Swedish Twin Study of Child and Adolescent Development were followed from childhood to
adolescence. ADHD symptoms were measured at age 8–9 and age 13–14 via parent-report, whereas substance use was assessed at
age 13–14 via self-report. Results revealed that hyperactive/impulsive symptoms predicted early-onset “sometimes” tobacco
use (adjusted odds ratios, 1.12, for one symptom count), controlling for inattentive symptoms and conduct problem behaviors.
There is no independent effect of inattentive symptoms on early-onset substance use. Children with persistent hyperactivity/impulsivity
(defined as scoring above the 75th percentile at both time points) had a pronounced risk of both early-onset tobacco and alcohol
use (adjusted odds ratios from 1.86 to 3.35, compared to the reference group). The associations between hyperactivity/impulsivity
and early-onset substance use were primarily influenced by genetic factors. Our results indicated that hyperactivity/impulsivity,
but not inattention, is an important early predictor for early-onset substance use, and a shared genetic susceptibility is
suggested to explain this association. 相似文献
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This study determined the working memory (WM) components (executive, phonological loop, and visual–spatial sketchpad) that best predicted mathematical word problem-solving accuracy of elementary school children in Grades 2, 3, and 4 (N = 310). A battery of tests was administered to assess problem-solving accuracy, problem-solving processes, WM, reading, and math calculation. Structural equation modeling analyses indicated that (a) all three WM components significantly predicted problem-solving accuracy, (b) reading skills and calculation proficiency mediated the predictive effects of the central executive system and the phonological loop on solution accuracy, and (c) academic mediators failed to moderate the relationship between the visual–spatial sketchpad and solution accuracy. The results support the notion that all components of WM play a major role in predicting problem-solving accuracy, but basic skills acquired in specific academic domains (reading and math) can compensate for some of the influence of WM on children’s mathematical word problem solving. 相似文献
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Correction to: Trends of Positive Youth Development Publications (1995–2020): A Scientometric Review
Qi Shaojie Hua Fengrui Zhou Zheng Shek Daniel T. L. 《Applied research in quality of life》2022,17(1):447-448
Applied Research in Quality of Life - A Correction to this paper has been published: https://doi.org/10.1007/s11482-020-09905-3 相似文献
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本实验利用条纹发生器产生正弦调制的条纹作视觉刺激,用NICOLETCA—1000平均仪,从枕骨隆起上方沿中线5cm处记录瞬态视觉诱发电位。实验用四种不同反差,十种空间频率,四名被试。结果表明瞬态视觉诱发电位(C_1—C_2)的峰值随反差的增加而变化,其在空间频率上有一定的分布,最敏感处落在3—5C/deg。在阈上刺激时,被试个体有差异,但分布趋势相似,最敏感处也为3—5C/deg,这和心理物理实验获得的调制传递函数(MTF)结果很吻合。从实验结果可以看到(C_1—C_2)值对反差变化是敏感的,它反映了人视觉系统对不同空间频率上的反差敏感性,可以把它与MTF相类比。 相似文献
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明代弘治至崇祯年间,曲阜孔氏《阙里志》和颜氏《陋巷志》共经历过四次编修,邹县孟氏《三迁志》也三次修纂。孔、颜、孟三氏家族志的每一次编纂,都呈现出特殊且鲜明的群聚现象,具体表现为编纂时间前后相因,体例内容相互借鉴,编修人员交集并处,修纂意旨彼此关切。这一现象出现的根本原因,在于孔、颜、孟三者在儒家文化体系中的内在联动性和外在整体性。同时,明代尊崇儒学,志书修纂盛行和三氏林庙修建,也是促成这一现象出现的文化动因。 相似文献