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Stefanie Vanbecelaere Katrien Van den Berghe Frederik Cornillie Delphine Sasanguie Bert Reynvoet Fien Depaepe 《Journal of Computer Assisted Learning》2020,36(4):502-513
For the training of academic skills, digital educational games with integrated adaptivity are promising. Adaptive games are considered superior to non-adaptive games, because they constantly assess children's performance, and accordingly adapt the difficulty of the tasks corresponding to the children's individual level. However, empirical evidence with regard to the effectivity of adaptive compared to non-adaptive games is limited. A study was conducted with 191 children from the third year of Kinder garten who were enrolled in one of three conditions, that is, playing an adaptive version of the reading game (RG), a non-adaptive version of the RG or training with pen-and-paper exercises. In all three conditions, children trained emergent reading (phonological awareness and letter knowledge) once a week for 30 min over a period of 5 weeks. Children's performance on cognitive (phonological awareness, letter knowledge, reading fluency) and non-cognitive (motivation, self-concept) factors was assessed. Results revealed a significant improvement in phonological awareness and letter knowledge in all conditions. However, no differences between the conditions were observed with respect to children's improvement on phonological awareness and letter knowledge or on their post-test scores for reading fluency. With regard to motivation and self-concept, again, no differences in these non-cognitive factors were observed across conditions. 相似文献
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砷污染原水的应急处理工艺研究 总被引:1,自引:0,他引:1
以我国目前广泛采用的常规净水工艺为基础,开展了水源突发性砷污染的应急处理工艺研究。试验结果显示:在原水中的As(Ⅴ)浓度超标10倍和50倍的情况下,通过增加混凝剂的投量,可将砂滤出水中的As(Ⅴ)浓度控制在10μg/L以下;但在原水As(Ⅴ)浓度超标100倍的极端情况下,则需在取水口处投加膨润土,采用吸附与增加混凝剂投量相结合的方法,才能将砂滤出水中的As(Ⅴ)浓度控制在10μg/L以下。混凝沉淀无法有效去除以分子形态存在的As(Ⅲ),需要预先将其氧化为As(Ⅴ)。当采用液氯作氧化剂时,其投加点对去除效果的影响不明显,但需确保有效氯(以Cl2计)与As(Ⅲ)的质量比〉2。混凝沉淀出水的浊度与残余的As(Ⅴ)浓度存在较好的线性关系,因此在时问较为紧迫的情况下,可以通过监测混凝沉淀出水浊度来问接反映对As(Ⅴ)的去除效果。 相似文献
4.
This study deals with evaluation of the impact of wastedump resulting from the phosphate ore dressing near the Mahamead Village (120 km north Aswan City), Aswan Governorate, Egypt, on the surrounding environment. The results indicate that the waste dump ecosystem contains elevated concentrations of Ca, Na, Cl~, SO^” and HCOJ as well as, relatively high concentrations of Fe, Mn, Pb and Cd. High pH (8.28–8.97) in all samples minimized the adverse effect on the soil and groundwater. The aerial parts of emergent weeds growing in the waste dump which used in this region as animal feed accumulate permissible limits of toxic metals. The wastedump can be a potential hazard to health and wildlife, if drainage from this dump (waste water) enters the Nile river. 相似文献
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以上海轨道交通2号线东延伸段车站工程为例,介绍了地铁车站智能照明控制系统的组成及功能,并分别阐述了智能控制照明系统的工作状态,消防模式及系统操作等内容,并总结了安装过程中操作重点和应急措施,以指导今后同类项目。 相似文献
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为全面客观地展现装备体系贡献的研究现状,综合运用文献计量法与内容分析法,对发文趋势和重点期刊进行描述性统计。分析核心作者、机构及其合作网络,应用2维分析框架开展实验式内容解读,通过关键词聚类与突现词检测探究知识基础与前沿热点。研究结果表明:作者合作网络比较分散,机构合作网络相对集中,数据来源以仿真试验和示例假定为主,研究方法以定量模型居多,微观层面的应用研究是当前的主流视角,装备体系贡献的研究重点呈现出“作战能力—作战效能—贡献率—体系结构”的演化路径。 相似文献
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Effortful control (EC) is an important developmental construct, associated with socioemotional growth, academic performance, and psychopathology. EC is defined as the ability to execute goal-directed behavior to inhibit or delay a prepotent response in favor of a subdominant response. Extant research indicates that EC may be multidimensional. Confirmatory factor analysis with a sample of 234 preschoolers was used to determine if tasks designed to measure EC were best described by hot (affectively salient) and cool (affectively neutral) dimensions or by a single factor. Analyses revealed that EC is best described by a single factor, even when variance associated with children's language skills was removed. This EC factor was strongly related to measures of academic performance and significantly less related to measures of socioemotional development. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
8.
African Americans and boys: Understanding the literacy gap, tracing academic trajectories, and evaluating the role of learning-related skills. 总被引:2,自引:0,他引:2
Matthews J. S.; Kizzie Karmen T.; Rowley Stephanie J.; Cortina Kai 《Canadian Metallurgical Quarterly》2010,102(3):757
In this study, the authors examined the racial and gender gap in the academic development of African American and White children from kindergarten to 5th grade. Their main goal was to determine the extent to which social and behavioral factors, including learning-related skills, problem behaviors, and interpersonal skills, explain these gaps and shed light on the academic difficulties specifically experienced by African American boys. The authors utilized the Early Childhood Longitudinal Study–Kindergarten Cohort (ECLS-K) sample and applied growth curve modeling. Learning-related skills explained the literacy development of African American boys over and above the effects of problem behaviors, socioeconomic status, and home literacy environment. Results suggest that emphasis placed on the behavior problems and the social risk factors associated with African American boys needs to be refocused and should be accompanied by increased efforts to improve learning-related skills in the classroom context and beyond. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
针对常规平面弹簧变形过程中运动端容易产生周向旋转从而造成振动和磨损的问题,设计了一种基于LEMs的平面弹簧,该弹簧由平面薄板加工成形且能实现平面外运动,具有体积小、易加工,结构简单及变形过程中运动端不发生周向旋转等优点。首先,基于悬臂梁模型和伪刚体模型分别推导了LEMs平面弹簧的刚度计算公式。其次,为验证所推导公式的正确性,建立了LEMs平面弹簧的ANSYS仿真模型,并将有限元分析结果与上述两种理论模型的计算结果进行了对比。结果表明,在变形较小的情况下由悬臂梁模型所推导的公式计算精度更高,在变形较大的情况下使用由伪刚体模型所推导的公式更为合适。最后,通过大量实例分析推导了两个公式的适用范围,并用一组数值算例证明了其正确性。 相似文献
10.
Theodore Spyropoulos 《Architectural Design》2009,79(6):82-87
Over the last four decades, the onset of computation has enabled architects and designers to employ generative patterns in their exploration of emergent social, material and spatial systems. Theodore Spyropoulos provides an overview of the field and discusses how it has been developed by the Design Research Lab (DRL) at the Architectural Association into an ‘Adaptive Ecologies’ agenda. In the context of parametric urbanism, the DRL has explored models of living through behavioural patterns found in nature, examining the role of the singular and the collective. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献