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991.
The motion of objects during motion parallax can be decomposed into 2 observer-relative components: translation and rotation. The depth ratio of objects in the visual field is specified by the inverse ratio of their angular displacement (from translation) or equivalently by the inverse ratio of their rotations. Despite the equal mathematical status of these 2 information sources, it was predicted that observers would be far more sensitive to the translational than rotational component. Such a differential sensitivity is implicitly assumed by the computer graphics technique billboarding, in which 3-dimensional (3-D) objects are drawn as planar forms (i.e., billboards) maintained normal to the line of sight. In 3 experiments, observers were found to be consistently less sensitive to rotational anomalies. The implications of these findings for kinetic depth effect displays and billboarding techniques are discussed.  相似文献   
992.
Procurement of organs from non-heart-beating cadaver donors raises concerns. Standards for optimal patient care during withdrawal of life-sustaining therapy are evolving and continue to be debated and studied. Consensus on specific procedures and methods has not been attained, however, and protocols for the procurement of organs from patients following the withdrawal of life-sustaining therapies may compromise the evolving standards and harm the patient and the attendant family. In addition, there is little evidence to suggest that such protocols will significantly increase the number of organs procured. "Non-heart-beating cadaver" protocols that do not give comprehensive attention to optimal patient/family care at the time of withdrawal of life-sustaining therapy ought not to be endorsed.  相似文献   
993.
A series of studies investigated the capacity of children between the ages of 7 and 12 to give free and informed consent to participation in psychological research. Children were reasonably accurate in describing the purpose of studies, but many did not understand the possible benefits or especially the possible risks of participating. In several studies children's consent was not affected by the knowledge that their parents had given their permission or by the parents saying that they would not be upset if the children refused. In contrast, other studies found that children were much more likely to stop their participation if the experimenter said explicitly that she would not be upset if they stopped. We suggest that experimenters should pay more attention to describing the possible risks and benefits of participation in research, and that they should also make it clearer to children that they are free to stop once they have begun.  相似文献   
994.
Abstract Two hundred forty high school students (120 male and 120 female) in India performed a moderately difficult multiple choice Arithmetic Reasoning task after undergoing short-term (40 minutes) cognitive treatment in the form of Attentional Skills Training. A 2 × 2 × 2 (Test Anxiety x Attentional Skills Training x Stress) design with separate analysis for boys and girls indicated these results: with intervention the high anxiety subjects under ego stress conditions, compared to their high-anxious control, low-anxious ego stress, or low-anxious control counterparts, reported the maximum significant improvement in performance on the Arithmetic Reasoning test. The low-anxiety subjects performed consistently well with or without treatment or stress conditions. The findings shed new light on the attentional theory of test anxiety, and it was reasoned that long-term effects of cognitive treatment be studied by using varied performance tasks (difficulty level controlled) on different gender and age groups across cultures.  相似文献   
995.
教师评分用语词义赋值特征的分析   总被引:2,自引:0,他引:2  
本研究运用模糊统计试验方法对教师的六组定性的评分用语词 (符号 )进行了经验赋值。参加赋值的是 2 66名小学教师。结果表明 ,六组评分用语词 (符号 )都是模糊概念 ,其中每种评分方式中处于最高等级的词 (符号 )的模糊度最小 ,处于中间等级的词 (符号 )的模糊度居中 ,处于最低等级的词 (符号 )的模糊度最大。词 (符号 )义的模糊度与评价的把握度呈现负相关 ,即词 (符号 )义越具体 ,模糊度越小 ,赋值的把握度就越大 ;反之 ,词义越含混 ,模糊度越大 ,赋值的把握度就越小。教师对各种评分用语词 (符号 )的赋值受百分制的“及格—不及格”的划分的影响 ,受评分方式中等级数目的影响 ,即增加评分等级会减少评分用语词 (符号 )的模糊度 ,增加赋值的把握度 ,还受评分用语词 (符号 )本身数量特征的影响。在各种评分方式中 ,评语词 (符号 )在心理量表上的距离是不等的。本研究的结果对教育评价的实践具有一定的参考价值。  相似文献   
996.
整体汉字字形识别过程探索   总被引:6,自引:0,他引:6  
本研究用微观发生范式探索了整体汉字和人工字的字形识别过程 ,主要获得以下结果 :1真字和人工字的正确提取率随呈现时间增长而提高 ,字形刺激的特征提取是一个有序的发展过程 ,字形识别加工受字特性 (真字与人工字 )和笔划数因素影响。2在以“十”为骨架和以“囗”为包围结构的字刺激中经常首先提取“十”或“囗”,而且首特征“十”或“囗”的提取不受字形熟悉性影响 ;笔划数变量仅对含“十”特征的字刺激的首特征提取产生影响。3在以上两类汉字中 ,“十”或“囗”作为首特征提取促进了字形识别加工过程。  相似文献   
997.
本项研究旨在探索 5 -1 1岁儿童元认知发展的规律 ,2 80名昆明市及路南县汉、撒尼族儿童参与了三项知觉实验 ,实验结果表明 :1儿童随年龄的增长 ,有关知觉组织策略的知识及自我监察的能力也逐渐发展 ,表现为系统观察、选取有效策略及计划性的增强。 2儿童对信息的加工不断深入 ,从表浅的加工过渡到详尽的加工 ,不仅要求补充必要的信息 ,而且主动搜索隐蔽的线索以促进识辨。3儿童自我评价从笼统、含糊逐渐向客观、全面发展。4路南儿童元知觉的发展晚于昆明儿童两年 ,但在路南的汉族儿童和撒尼族儿童之间不存在显著差异 ,说明文化教育对儿童元知觉发展的重要影响。  相似文献   
998.
众教领袖会温沙共画宏图护寰球──记世界宗教与环境保护首脑会议谢宗信,张继禹,曾传辉在1995年中国道教的对外交往中,有一起具有非同寻常意义的事件。那就是作为我国古老的民族性宗教──道教,第一次独立地派出它的代表,走出国门,出席世界宗教与环境保护首脑会...  相似文献   
999.
A methodology for the quantitative evaluation of observed workload was proposed. The model was designed to provide point estimations of observed workload at any time during the performance of a set of tasks. The model was also designed to provide information about the task-scheduling strategies used to complete a set of tasks. The proposed model was then tested with data from a full mission flight simulation. The model predictions correlated significantly with expert ratings of workload management made during the flight simulation. The model was also able to distinguish between low- and high-performing aircrews when performance was based on the number of errors made during flight simulations.  相似文献   
1000.
This comment responds to an article by Range and Cotton (1995) on reporting of parental permission and child assent procedures in published articles for 4 psychology journals. Issue is taken with the assumptions, methodology, interpretations, and implications of listing researchers in the Range and Cotton article. There is no evidence researchers failed in their ethical obligations or that children were put at risk. Reporting permission/assent in publications is not an ethical requirement. Listing researchers as "failing" to do something not part of an ethical code is lamentable. Too many unfortunate implications and problems can be derived from Range and Cotton's analysis and conclusions.  相似文献   
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