Instrumenting Mathematical Activity: Reflections on Key Studies of the Educational Use of Computer Algebra Systems

This paper examines the process through which students learn to make functional use of computer algebra systems (CAS), and the interaction between that process and the wider mathematical development of students. The result of ‘instrumentalising‘ a device to become a mathematical tool and correspondingly ‘instrumenting’ mathematical activity through use of that tool is not only to extend students' mathematical technique but to shape their sense of the mathematical entities involved. These ideas have been developed within a French programme of research – as reported by Artigue in this issue of the journal – which has explored the integration of CAS – typically in the form of symbolic calculators – into the everyday practice of mathematics classrooms. The French research –influenced by socio-psychological theorisation of the development of conceptual systems- seeks to take account of the cultural and cognitive facets of these issues, noting how mathematical norms – or their absence – shape the mental schemes which students form as they appropriate CAS as tools. Instrumenting graphic and symbolic reasoning through using CAS influences the range and form of the tasks and techniques experienced by students, and so the resources available for more explicit codification and theorisation of such reasoning. This illuminates an influential North American study– conducted by Heid – which French researchers have seen as taking a contrasting view of the part played by technical activity in developing conceptual understanding. Reconsidered from this perspective, it appears that while teaching approaches which ‘resequence skills and concepts’ indeed defer – and diminish –attention to routinised skills, the tasks introduced in their place depend on another –albeit less strongly codified – system of techniques, supporting more extensive and active theorisation. The French research high lights important challenges which arise in instrumenting classroom mathematical activity and correspondingly instrumentalising CAS. In particular, it reveals fundamental constraints on human-machine interaction which may limit the capacity of the present generation of CAS to scaffold the mathematical thinking and learning of students. This revised version was published online in July 2006 with corrections to the Cover Date.     

计算机代数应用中的一个半逆序算法*

为了克服计算机代数应用中出现的"中间表达式爆炸"的困难,本文提出一种半逆序算法,将中间表达式在运算过程中以符号形式冻结起来,到求解的最后阶段予以解冻,从而避免了因存贮空间不足而导致的溢出.文中简述了该算法在非线性振动、冷却塔动力优化和非线性水波问题中的应用,证实了算法的有效性.     

Instructional Supports for Representational Fluency in Solving Linear Equations with Computer Algebra Systems and Paper‐and‐Pencil

This research addresses the issue of how to support students' representational fluency—the ability to create, move within, translate across, and derive meaning from external representations of mathematical ideas. The context of solving linear equations in a combined computer algebra system (CAS) and paper‐and‐pencil classroom environment is targeted as a rich and pressing context to study this issue. We report results of a collaborative teaching experiment in which we designed for and tested a functions approach to solving equations with ninth‐grade algebra students, and link to results of semi‐structured interviews with students before and after the experiment. Results of analyzing the five‐week experiment include instructional supports for students' representational fluency in solving linear equations: (a) sequencing the use of graphs, tables, and CAS feedback prior to formal symbolic transpositions, (b) connecting solutions to equations across representations, and (c) encouraging understanding of equations as equivalence relations that are sometimes, always, or never true. While some students' change in sophistication of representational fluency helps substantiate the productive nature of these supports, other students' persistent struggles raise questions of how to address the diverse needs of learners in complex learning environments involving multiple tool‐based representations.     

关于高等代数的结论及证明教学的思考与探讨

从教学方向、教学过程、教学拓展三个方面探讨了高等代数的结论及证明的教学.     

The Co-Emergence of Machine Techniques, Paper-and-Pencil Techniques, and Theoretical Reflection: A Study of Cas use in Secondary School Algebra

This paper addresses the dialectical relation between theoretical thinking and technique, as they co-emerge in a combined computer algebra (CAS) and paper-and-pencil environment. The theoretical framework in this ongoing study consists of the instrumental approach to tool use and an adaptation of Chevallard’s anthropological theory. The main aim is to unravel the subtle intertwining of students’ theoretical thinking and the techniques they use in both media, within the process of instrumental genesis. Two grade 10 teaching experiments are described, the first one on equivalence, equality and equation, and the second one on generalizing and proving within factoring. Even though the two topics are quite different, findings indicate the importance of the co-emergence of theory and technique in both cases. Some further extensions of the theoretical framework are suggested, focusing on the relation between paper-and-pencil techniques and computer algebra techniques, and on the issue of language and discourse in the learning process.With the collaboration of André Boileau, Fernando Hitt, Denis Tanguay, Luis Saldanha, and José Guzmán     

大类招生线性代数教学方法初探——以浙江大学为例

根据探究式学习理论,让学生在教师的指导下自主地解决教师预先提供的大量问题,称之为基于问题的探究式教学法.这种教学法可以在有限的时间内让学生掌握大量的知识并锻炼解决问题的能力.相比传统的教学模式,该方法能更好的培养现代社会发展所需要的人才.我们给出了该方法在线性代数课程上的实施过程.     

线性代数与空间解析几何教学内容改革实践

科学技术的发展深刻地影响着大学教育体系和教育模式 ,大学教育的改革势在必行 ,面向二十一世纪高等数学教学改革是高等教育改革中一个非常重要的组成部分 ,线性代数与空间解析几何是高等数学的三大模块之一 ,本文主要介绍面向二十一世纪高等数学教学改革教材《线性代数与空间解析几何》教学内容的改革实践 .     

《线性代数（非数学专业）》整体教学的实践与认识

首先明确了《线性代数（非数学专业）》整体教学的目的和实践的过程,其次从学生构建《线性代数》知识、技能和思想方法的角度总结了《线性代数》整体教学实践的一些体会,最后指出《线性代数》整体教学应把握数学观念,更好地将启发式教学与问题解决结合起来．     

Factorization of the Loop Algebra and Integrable Toplike Systems

With any Lie algebra of Laurent series with coefficients in a semisimple Lie algebra and its decomposition into a sum of the subalgebra consisting of the Taylor series and a complementary subalgebra, we associate a hierarchy of integrable Hamiltonian nonlinear ODEs. In the case of the so(3) Lie algebra, our scheme covers all classical integrable cases in the Kirchhoff problem of the motion of a rigid body in an ideal fluid. Moreover, the construction allows generating integrable deformations for known integrable models.     

一类反对称loop代数及其应用

构造了一类3×3的反对称loop代数,由此设计了一个含5个位势函数的等谱问题;利用屠格式导出了一个Liouville可积系统,且拥有双Hamilton结构.     

一个Lie代数的子代数及其相关的两类Loop代数

本文构造了Lie代数A2的一个子代数A2,通过选取恰当的基元阶数得到相应的一个loop代数A2,由此设计一个等谱问题,利用屠格式得到了一个新的Liouville可积的Hamilton方程族.作为其约化情形,得到了一个非线性有理分式型演化方程.再由一个矩阵变换,得到了换位运算与A2等价的Lie代数A1的一个子代数A1,将A1再扩展成一个新的高维loop代数G,利用G获得了所得方程族的一类扩展可积系统.     

关于高等代数课程教学改革和教学实践的几点体会

高等代数是大学本科数学专业一门重要的基础课程,但由于该课程的内容、思想的抽象性,传统的教学模式很难使大一的学生入门,也很难培养学生对高等代数的兴趣.若将其与解析几何、数学软件、数学建模等结合起来,并将其内容的先后顺序做适当的调整,能使其内容具体化、生动化.更易适应大一新生的学习方式.切实培养大学生的数学素质,提高教学质量.     

广义baby TKK代数一类boson表示

利用文[3]中的结论构造群代数与对称代数在文[4]的基础上给出了广义baby TKK代数G(~T)的一类boson场表示.     

工科高校《应用近世代数》课程体系改革探讨与思考

文章从阐述近世代数在工科高校教学中的重要意义及对现有教材存在的一些问题的探讨出发,从几个方面考察了目前工科高校《应用近世代数》课程体系教学改革的必要性,并提出了自己的一些设想,期望能为工科高校的《应用近世代数》教学改革及高校教育改革抛砖引玉.     

关于Brunnian辫子群的相对李代数的基

Brunnian辫子群与球面上的同伦群关系密切.在本文中,研究了Brunnian辫子群相对于纯辫子群的相对李代数L^P(Brun_n),通过其与Brunnian辫子群相对于自由群的相对李代数L⁽F_n-1)(Brun_n)的关系,并借助自由群的李代数L(F_n-1)的Hall基给出相对李代数L^P(Brun_n)的基.     

仿射系统局部强可控性的充分条件

本文讨论仿射系统的局部强可控性.文中证明了如果系统在x_0点满足可控性秩条件,并且集合{x|dim sp{g_i(x)}相似文献   

“抽象代数”教学中的素质教育

从“抽象代数”课程的角度,围绕“建立代数体系、研究代数体系、区分代数体系、应用代数体系”四个方面,讨论教学过程中如何培养学生的数学能力和数学素质,如何实施素质教育.     

信息与计算科学专业应用型人才培养模式的研究

分析了信息与计算科学专业课程教学的特点和存在的教与学的矛盾.并以《高等代数》为试点,在教学实践中试行教学改革,积极探索教学与实际相结合与计算机信息有机结合的教学模式,在应用型人才培养方面取得显著成效.对信息与计算科学专业应用型人才培养有一定的借鉴作用.     

“金课”背景下强化线性代数应用教学的实践与探索

线性代数课程具有高度的抽象性,再加上课时等多方面限制,使得学生学起来感觉非常枯燥.针对此问题,在线性代数课程中,适当增加应用的讲解,以增加学生对于相关知识应用的认知,提高学生综合利用线性代数知识解决问题的能力.通过调查问卷,分析了在线性代数课程中增加应用知识讲解的经验、存在的问题及应对措施.