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991.
多媒体学习中的通道效应认为,学习者对"画面+声音解说"组成的视听双通道材料的识记或理解效果要好于"画面+视觉文本"组成的视觉单通道材料,而逆转通道效应则发现了与之相反的结果。针对以往研究缺陷,重新采用元分析技术,以保持测验和迁移测验作为结果变量,考察通道效应的稳定性。经文献检索、纳入与排除后,共获91篇符合元分析的文献。经数据事先合并处理后,保持测验上生成94个独立效应量(8088人),迁移测验上生成83个独立效应量(6664人)。主效应检验发现:视听双通道在保持测验(d=0.24)和迁移测验(d=0.25)上均显著高于视觉单通道;调节效应检验发现:呈现步调、画面动态性和材料时长在保持测验和迁移测验上均对通道效应起到调节作用,通道效应主要在系统步调(d_(保持)=0.43,d_(迁移)=0.44)、动态画面(d_(保持)=0.50,d_(迁移)=0.59)及短时材料(d_(保持)=0.38,d_(迁移)=0.33)条件下出现;所有结果均未发现逆转通道效应。结论认为:相比视觉单通道,当图文信息以视听双通道呈现时更有利于促进学习者对多媒体学习材料的识记和理解,支持了多媒体学习认知理论;呈现步调、画面动态性以及材料时长是通道效应的重要边界条件。  相似文献   
992.
Although the presentation of extraneous (i.e., irrelevant or unnecessary) information hinders learning, it is unclear whether and how layout and pacing influence this effect. In two experiments, participants learned how the heart functions using four different layouts: a diagram presented without unnecessary text (diagram only), with unnecessary text separated from the diagram (separated) or integrated into the diagram (integrated), or with separated unnecessary text and the instruction to integrate (integration instruction). In Experiment 1, study time was self‐paced for half of the participants and system paced for the other half. There were no effects of layout and of pacing on learning, although system pacing was more effortful than self‐pacing. In Experiment 2, which was system paced and employed eye tracking, the integrated condition showed worse learning outcomes than the separated condition. Moreover, in the integrated condition, participants made more integration attempts between the unnecessary text and the diagram than in the separated condition.  相似文献   
993.
We investigate halo effects from agency behaviors and communion behaviors in different social contexts. According to the salient dimension model, attributes elicit halo effects on the ratings of other, unrelated attributes when they are relevant in a situation. Given that communion behaviors are more relevant in social and care‐related jobs, they should elicit stronger halo effects than agency behaviors in this context. In the context of scientific and technical jobs, this difference should be weakened or even reversed. Three experiments support the predicted interaction of context and behavior on halo effects. This interaction was stronger for negative than for positive behaviors. These results have implications for understanding the basic processes of halo effects as well as their real‐world effects in job‐related contexts.  相似文献   
994.
995.
A novel, instrumented microindentation technique was successfully used to measure the temperature associated with the martensitic transformation leading to the recovery of plastic strain in a Nickel–Titanium (NiTi) shape memory alloy. Following a standard indentation cycle, the indenter was partially unloaded such that a good contact was maintained between indenter and specimen surface. The onset and finish temperature of the martensitic transformation, the associated volume contraction, and the amount of the recovered plastic deformation were determined by quantifying the indenter displacement as a function of temperature. These experiments were compared to conventional measurements of the transformation temperature by differential scanning calorimetry and compression testing.  相似文献   
996.

A model of the structure of two-dimensional foam (cells separated by circular arcs (films) meeting at threefold vertices) is considered. Films that are so curved as to be nearly semicircular arcs are problematic for conventional foam structure computations, which aim to identify the pressures needed to achieve specified bubble areas. When the films have near semicircularity, tiny variations in pressure can lead to large changes in the computed bubble area, and hence a failure to meet the specified targets. A new algorithm for determining foam structure is presented. It is based on 'freezing' most of the system, except the nearly semicircular arcs, and then finding the particular bubble pressures associated with the latter via an analytic approximation. This procedure is shown to work well for structure relaxation in a small bubble cluster. Large relaxed bubble clusters are considered briefly at the end of the paper.  相似文献   
997.
An inverse “smaller is stronger” trend is predicted on the basis of molecular dynamics simulations of α-titanium (Ti) single-crystal nanopillars orientated for double prismatic slips when the nanopillars are less than 7?nm wide. This trend is attributed to a significant increase in the surface energy due to the nucleation and propagation of edge dislocations on the surface of the pillars.  相似文献   
998.
The relationship between the Flynn effect and ability differentiation is investigated in a reanalysis of published data on Estonian student cohorts tested in 1933/36, 1997/98 and 2006 on the National Intelligence Test (Must, te Nijenhuis, Must, & van Vianen, 2009). To determine whether there was a relationship we computed the vector correlation between the Flynn effects (d) and the change in the g loading (Δg) between measurement occasions for each of the 10 NIT subtests and for each of the seven cohort comparisons, giving a total N of 70 effect sizes. The association between d and Δg was robustly negative (indicating that the Flynn effects were negatively associated with changes in the g loading of subtests) for all cohort comparisons, with values of r ranging from −.100 to −.461 (N = 10). When all effect sizes were analyzed together, the vector correlation was found to be −.281 (p ? .05, N = 70). This indicates a significant association between the Flynn effect and ability differentiation. Possible causes of this association are discussed.  相似文献   
999.
Using data from the longitudinal NICHD Study of Early Child Care and Youth Development (N = 1364), this study examined the association between mothers' sensitivity and children's externalizing behavior from preschool to preadolescence. Externalizing behavior declined on average across this period with a slowing of this decline around middle childhood. Maternal sensitivity remained relatively stable on average, and there was significant variation across mothers. A decrease in maternal sensitivity from ages 3 to 11 was related to an increase in externalizing behavior from ages 4 to 12. A model-based test of the direction of the effect suggested that the association between changes in maternal sensitivity and externalizing behavior from ages 4 to 11 was driven by child effects on mothers and not vice-versa. Between late preschool age and preadolescence, the behavior problems of children appear to strongly influence the sensitive support of mothers. Practical implications were discussed in light of these findings.  相似文献   
1000.
ABSTRACT

We examined whether enhancing (vs. not enhancing) the emotionality of a referent public good influences the subsequent valuation of a target public good. We predicted that it would and that the directionality of its impact would depend on a fundamental cognitive process – categorisation. If the target and referent goods belong to the same domain, we expected that the effect on the target would be in the same direction as the emotional enhancement of the referent (assimilation effect). However, if the target and referent goods belong to different domains, we expected that the effect on the target would be either negligible or in the opposite direction to that of the emotional enhancement of the referent (null or contrast effect). In Experiment 1 we examined the impact of emotionally enhancing a referent public good on feelings towards a target public good, whereas in Experiment 2 on the willingness to contribute towards a target public good. The results support the predicted interaction, which was driven by an assimilation effect for same-domain goods and a null effect for different-domain goods. In doing so, the present findings highlight the interplay between cognition and emotion in the valuation of public goods. We discuss theoretical and practical implications.  相似文献   
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