Concreteness fading in learning secondary school physics concepts

Concreteness fading has been proposed as a general instructional approach to support learning of abstract mathematics and science concepts. Accordingly, organizing external knowledge representations in a three-step concrete-to-idealized sequence should be more beneficial than the reverse, concreteness introduction, sequence. So far, evidence for the benefits of concreteness fading come mainly from studies investigating learning of basic mathematics concepts. Studies on learning natural science concepts are scarce and have not implemented the full three-step-sequence. In an experimental classroom study (N = 70), we compared concreteness fading and concreteness introduction in high school science education about electromagnetic induction using a detailed assessment. Furthermore, we explored whether these sequences differentially affect the use of the different representations during instruction. Both sequences were equally effective and there were no differences in using the representations. We discuss why our results question the proposed advantages of concreteness fading and highlight conceptual differences and learning goals across domains.     

试论徽州地域文化对戴震重知思想的影响

戴震是我国18世纪百科全书式的学术巨擘,被后世诸多学者奉为中国启蒙先驱。戴震出生地徽州,18世纪以商贾兴盛、儒风帜盛、宗法礼制完备著称于世,有东南邹鲁之称的美誉。戴震思想重知的特色,与徽州地域文化有千丝万缕的联系,本文试图在学术观念史和徽州区域文化的双向中来展开对戴震重知思想形成的深层区域社会背景的探究。     

如何有效地诊断与维修发动机常见的机械故障

结合多年工作和实践，对发动机常见的机械故障的诊断与维修做进一步的总结介绍，便于专业及维修人员参考。     

UWB超宽带无线技术

超宽带UWB是一种无线接入技术,拥有超宽带、极低功率谱密度两大特点,脉冲信号的产生,信号的调制以及信号的快速捕获、同步与检测是超宽带无线通信的技术关键。超宽带在多媒体内容日益丰富的消费电子应用中,具有良好的应用前景。     

《新编大学英语课文辅导》中几个阅读理解问题的探讨

文章指出了《新编大学英语课文辅导》一书参考译文中的15处不恰当的中文翻译，并从词义、语法结构、上下文以及文化背景等方面进行了认真分析，阐明了自己的见解，并以此强调了独立阅读的重要性。     

对档案馆“服务壁垒”的若干思考

文章就“如何认识档案馆服务工作中的‘服务壁垒’的内涵与具体表现”、“如何认识档案馆服务工作中的‘服务壁垒’的成因与危害”以及“如何克服档案馆服务工作中的‘服务壁垒’”问题谈了作者的思考与认识。     

树立和坚持正确的事业观、工作观和政绩观

胡锦涛同志提出树立和坚持正确的事业观、工作观和政绩观，具有极强的针对性和现实意义。文章就树立和坚持正确的事业观、工作观和政绩观的科学内涵进行了分析，提出了实现的路径。     

非共识项目的设立给基础研究源头创新带来新希望

通过科学基金“地表柯石英的模拟合成及其形成机制的研究”项目的评审、批准和研究的具体实例,阐明基金评审制度改革,设立非共识项目的政策,极大地鼓励和推动了基础研究的原始创新。     

Developing children's conceptual understanding of area measurement: A curriculum and teaching experiment

The present study examined the effectiveness of three instructional treatments which had different combinations of mathematical elements regarding 2-dimensional (2-D) geometry and area measurement for developing 4th-grade children's understanding of the formulas for area measurement and their ability to solve area measurement problems. Participants were 120 fourth graders. The results showed that the enriched curriculum, involving the geometry motions and area measurement connections effectively facilitated children's mathematical judgments and explanations demanding high-level conceptual understanding. The instructional curricula accentuating only 2-D geometry or numerical calculations for area measurement did not exhibit such effectiveness. Interview data revealed that the geometric operations of superimposition, decomposition, re-composition as well as the concept of congruence were deemed essential by children for the conceptualization of the formulas for area measurement.     

数学优秀课成长的基础、过程与方法

以分数为目标、对教学内容理解表面化和教学设计无基本章法是造成课堂教学平庸、低效的主要原因,因此在关注优秀课的表现形式与评价标准的同时,更应关注优秀课成长的基础、过程与方法。超越应试是优秀课的基本要求与历史使命;理解数学是教学设计与优秀课成长的基础,而好的教学设计框架则是优秀课成长的过程与方法。