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101.
In two experiments, we investigated emergent conditional relations in pigeons using a symbolic matching-to-sample task with temporal stimuli as the samples and hues as the comparisons. Both experiments comprised three phases. In Phase I, pigeons learned to choose a red keylight (R) but not a green keylight (G) after a 1-s signal. They also learned to choose G but not R after a 4-s signal. In Phase II, correct responding consisted of choosing a blue keylight (B) after a 4-s signal and a yellow keylight (Y) after a 16-s signal. Comparisons G and B were both related to the same 4-s sample, whereas comparisons R and Y had no common sample. In Phase III, R and G were presented as samples, and B and Y were presented as the comparisons. The choice of B was correct following G, and the choice of Y was correct following R. If a relation between comparisons that shared a common sample were to emerge, then responding to B given G would be more likely than responding to Y given R. The results were generally consistent with this prediction, suggesting, for the first time in pigeons, the emergence of novel relations that involve temporal stimuli as nodal samples.  相似文献   
102.
The purpose of this study is to investigate the effect of computer-assisted learning integrated with metacognitive prompts on elementary students’ affective skills on the subject of electricity. The researchers developed educational software to enable students to easily and comprehensively learn the concepts in the subject of electricity. A case study method was used. Eighteen students from the seventh grade (12–13 years) participated in the study. Students’ views on their performances while using educational software and the impact of the software on their affective skills towards the subject of electricity were examined. Data were collected by open-ended questions in the educational software. According to the research results, there were students who had negative attitudes and perceptions before starting to learn about the subject of electricity. Interactive activities, animations, and visual experiments in the educational software were effective in overcoming the students’ negative attitudes and perceptions about the subject. Besides, students who assessed their own performances during the learning process believed themselves to be more successful over time. In the light of the research results, some suggestions are made for future studies.  相似文献   
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Personalization has been widely used in Web-based instruction (WBI). To deliver effective personalization, there is a need to understand different preferences of each student. Cognitive style has been identified as one of the most pertinent factors that affect students' learning preferences. Therefore, it is essential to investigate how learners with different cognitive styles interact with WBI programs. This paper presents an empirical study, which examines the effects of cognitive styles on students' learning patterns and the effects of learning patterns on their learning performances. Riding's cognitive style analysis was used to identify the students' cognitive styles. Data mining, especially a clustering technique, was used to analyze the results. It was found that field independent students frequently used an alphabetical index whereas field dependent students often chose a hierarchical map. Such learning patterns also have great effects on their performance, especially for field dependent students.  相似文献   
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将有限表现模限制在平坦维数≤1,得到有限平坦表现模及其性质,利用有限平坦表现模类给出了其Ext-正交模即FFP-内射模,刻画了右F-凝聚环与右F-正则环。在环的几乎优越扩张S≥R下,证明了S为右F-凝聚环当且仅当R为右F-凝聚环,S为右F-正则环当且仅当R为右F-正则环。  相似文献   
106.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
107.
ABSTRACT

The aims of this study were to perform the cross-cultural adaptation of the Borg Rating of Perceived Exertion (RPE) 6–20 Scale to Brazilian Portuguese language and to start testing its validity and reliability. After performing the cross-cultural adaptation of the Scale, concurrent and discriminative validity, and reliability were determined on a treadmill in young (18–30 years) and older adult women (60–75 years). Considering young and older adult women, RPE presented high and moderate positive correlation with heart rate and high and low positive correlation with oxygen consumption, respectively. Older adult women presented RPE (11 ± 2) significantly higher than young ones (8 ± 1) exercising at the same absolute intensity. Intraclass coefficient correlation was excellent for RPE to young and older adult women. The Scale presented concurrent validity only to young adult women, whereas it presented discriminative validity between such groups of women. Moreover, the scale is reliable to young and older adult women.  相似文献   
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以央视《创业英雄汇》节目的233个创业项目为研究对象,设计指标体系并结合案例分析法对投资人的信息 需求进行分析。分析结果表明:目前投资人对农林牧渔业更加关注项目规划信息,对轻工食品业更加关注产品组合以 及供应商方面的信息,对信息产业更加关注技术环境信息,对服务业更加关注竞争格局的信息。最后在此分析的基础 上提出3 点建议。  相似文献   
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