《复变函数》教学基本要求

<正> 复变函数是高等工科学校有关专业的基础课,通过本课程的学习,使学生初步掌握复变函数的基本理论和方法,为学习有关专业课和扩大数学知识面提供必要的数学基础。一、复数与复变函数     

复变函数的可视化问题

首先简单介绍了复变函数基础理论的内容可视化和其基于数学软件的直观演示资源建设情况,然后通过幅角函数可视化问题介绍利用数学软件开发应用于数学教学实践的演示素材的方法,解决了Mathematica中的标准幅角函数不能直接表示复数幅角变化量的问题.     

函数论

函数论通常指的是复变函数论和实变函数论。它是微积分学的深入和发展,是现代数学的基础之一。复变函数的研究对象是变量取复数值的函数,它是数学中发展成熟、内容丰富的一个分支。它又分出诸如复变函数的逼近论,整函数与亚纯函数的值分布理论、复变函鼓的几何理论以及多复交函数论等分支。作为大学有关专业必修课程的复变函数则主要讲述解析函数的基本理论和有关方法:积分论、级数理论和保形映照理论。对复变函数的研究始于十八世纪,瑞士的欧拉(公元1707-1783年),法国的达兰贝尔(公元1717-1783年)和拉普拉斯(公元1749-1827年)等是创建复变函数论这门学科的先驱。到十九世纪,法国的柯西(公元1789-1957年)、德国的黎曼(公元1826-1866年)与     

关于复数产生之说

<正> 复变函数是属于数学中一部分比较特殊的理论.这门学科的诞生,当初并非由于实际问题的需要,而是数学理论发展到一定阶段的产物.因此,研究一下形成这门学科的最基本的概念——复数,怎样由于数学内部矛眉的发展而必然地产生出来,这对人们对于教学的认识和教学本身的发展都是有意义的.同时在复变函数的教学中,每个教师都必须     

a~(1/n)与 a~b的意义

<正> a~(1/n)(a 是复数,n>1是正整数)与a~b(a,b 都是复数)这两个符号的定义分别在中学代数课本与大学复变函数课本中给于介绍,但在中学课本中介绍得不够完整,而大学课本中对此的介绍又与中学课本所下定义有矛盾.下面谈点我们自己的看法,希望能得到专家,同行的指正.     

重复变函数(上)

本文讨论特定的一种超复数系(称为重复数环)上的函数。它与多元复变函数、双曲方程发生联系。使我们能用复变函数方法去研究双曲方程。     

复数域中的微积分基本定理

根据复变函数与实变函数在许多概念、理论和方法上的相似之处,将实数域上的微积分基本定理适当推广至复数域.此外,给出一个复平面区域上的每一个解析函数都有原函数的等价条件.     

以问题为导向的复变函数教学与实践

复分析在数学的众多分支、物理学、工程领域有着重要应用,因此它是众多工程类专业的必修课程.传统的复变函数教学方式存在着一些不足,并不完全适合当下的学生.这导致相当数量的学生觉得复变函数枯燥而不易学习.为解决这一问题,教师可以通过有效的启发,并以讨论问题的方式开展复变函数的教学.这种方式不仅有益于提高学习效率并且可以增加学生的学习兴趣.     

正交双复数空间变换与流体问题的边界元

在确立特殊的正交双复数空间及正交双复变函数的概念上,建立其相应的运算规则及空间保角变换的概念,并用这些概念,探索了它在流体边界元中的应用前景.研究表明,所建立的概念和特殊表达算符,能够有效地将平面复数的概念扩展至三维空间,并可构成数理应用领域的一个有效工具.     

关于复变函数的微分中值定理及其证明

<正> 复变函数论是数学分析在复数域中的进一步发展和推广,它的许多概念和定理与数学分析中的理论相类似.复变函数的极限、连续以及导数与微分的定义.形式上和数学分析中一元函数的相应定义一致.比如,在数学分析的微分学中,对一元函数的导数是这样定义的:设函数y=f(x)在点x_0的某一邻域内有定义(包括x_0点),当自变量x在x_0处有增量(?)时,相应地函数有增量△y=f(x_0+△x)-f(z),当△x→0时,比值的极限存在,称此极限为函数y=f(x)在x_0处的导数.记为f’(x).复变函数的导数定义为:设函数w=f(z)在     

如何不用复数讲解常系数线性微分方程

在高等数学课程中,复指数函数及其导数知识的严格讲解,通常要比微分方程知识的讲解晚很多.这使得微分方程的教学在逻辑上有些不足.用复值函数解的复系数线性组合推导出实值函数解,在教学实践中,学生经常感到迷惑.不以复数的任何知识作为前提,给出了常系数微分方程的一种自然的讲解方法.     

解决高等数学教学问题的七点措施——以衡阳师范学院为例

本文简要分析了当前高校高等数学教学所面临的几个突出问题,在此基础上结合衡阳师范学院高等数学教学实际,从七个方面阐述了如何加强高等数学教学以提高教学质量.     

Classroom note A Capstone Course for pre-service secondary mathematics teachers

In the decade since the first of three National Council of Teachers of Mathematics Standards documents was published, there has been an unprecedented amount of attention to, and activity surrounding, issues in mathematics education at all levels. The Department of Mathematics at Baylor University has taken the first of several necessary steps to provide future mathematics teachers with the best possible preparation. The paper reports efforts at Baylor University to involve their secondary mathematics education students in new teaching methods and the use of technology in the teaching of mathematics at the secondary level. A number of examples are given of how pre-service mathematics teachers connect ideas across mathematics courses and develop personal self-confidence and a disposition to seek, evaluate, and use quantitative and spatial information in problem-solving.     

On the Betti numbers of Alexandrov spaces

In this note we show that the total Betti number of an Alexandrov space is bounded above by a constant depending only on the dimension, the diameter and the lower bound on curvature.Research supported in part by a Grant from Department of Mathematics, University of South Carolina.     

On the continuity of a Lagrangian multiplier function in input optimization

We show that a Lagrangian multiplier function in input optimization is generally discontinuous on regions of stability and then we find conditions for its continuity.Research partly supported by the Natural Sciences and Engineering Research Council of Canada.Presented at TIMS/ORSA Meeting in Boston, Massachusetts, April 29-May 1, 1985.The contribution of this author is part of his M.Sc. thesis in Applied Mathematics at McGill University.     

A Sino-German semi-virtual seminar in mathematics education

In summer 2006 the University of Education in Weingarten, Germany, and East China Normal University, Shanghai, performed a semi-virtual seminar with mathematics students on “Mathematics and Architecture”. The goal was the joint development of teaching materials for German or Chinese school, based on different buildings such as “Nanpu Bridge”, or the “Eiffel Tower”. The purpose of the seminar was to provide a learning environment for students supported by using information and communication technology (ICT) to understand how the hidden mathematics in buildings should be related to school mathematics; to experience the multicultural potential of the international language “Mathematics”; to develop “media competence” while communicating with others and using technologies in mathematics education; and to recognize the differences in teaching mathematics between the two cultures. In this paper we will present our ideas, experiences and results from the seminar.     

关于外招生高等数学教学的思考

针对当前暨南大学外招生高等数学教学中存在的问题,从外招生的不同内在需要和个性特点出发,对他们学习高等数学需要的教学方法展开探讨,以期能够提高教学质量,实现对外招生高等数学教学最优化.     

Newton interpolation at Leja points

The Newton form is a convenient representation for interpolation polynomials. Its sensitivity to perturbations depends on the distribution and ordering of the interpolation points. The present paper bounds the growth of the condition number of the Newton form when the interpolation points are Leja points for fairly general compact sets K in the complex plane. Because the Leja points are defined recursively, they are attractive to use with the Newton form. If K is an interval, then the Leja points are distributed roughly like Chebyshev points. Our investigation of the Newton form defined by interpolation at Leja points suggests an ordering scheme for arbitrary interpolation points.Research supported in part by NSF under Grant DMS-8704196 and by U.S. Air Force Grant AFSOR-87-0102.On leave from University of Kentucky, Department of Mathematics, Lexington, KY 40506, U.S.A.     

生灭矩阵重构三弦乐谱

三弦乐谱可由三对角复矩阵生成,人们听到的声音由其谱决定,自然要求此矩阵有实谱.如同量子力学,模型的描述是复算子,可观测量是实的.换言之,所述的三对角复矩阵应是关于某个测度的复内积空间上的自共轭算子.熟知,生灭Q矩阵可配称,自然就是自共轭的.我们将要介绍最新的一个代表性成果:对于相当广泛的自共轭三对角复矩阵,总可以构造出一个生灭Q矩阵,使得两者等谱(简单地说,两者有完全相同的特征值).这个问题浅显易懂,但我们曾在不同时期,从概率论、统计物理和计算数学三个不同的角度研究过,经历了漫长的求索岁月.本文是根据作者在"International Conference on Probability Theory and Its Applications"(湖南文理学院,2018年7月)的报告整理而成.共分三部分:1)生灭过程的新应用;2)从(非对角线元素非负的)实可配称矩阵到复可配称矩阵;3)此课题的来源(计算)及其判别准则的应用(统计物理及量子力学).     

Das Wissen um Unterschiede in den kognitiven Strukturen von Schülerinnen und Schülern als Erklärung von Unterrichtsbeiträgen

It is reported about a longitudinal study run at the Institute of Cognitive Mathematics of the University of Osnabrueck, in which pupils’ verbal and text productions from mathematics lessons at a grammar school are analysed by means of cognitive theoretical methods. First of all, a teaching scene from an instruction to probability calculus and further text productions from an introductory lesson about exponential functions are analysed, in which five pupils take part whose cognitive structures have been assessed and classified in individual examinations. The characteristics brought out according to these teaching scenes indicate different ideas and thinking processes of the pupils. The second part shows that the pupils’ behaviour described is not only to be regarded in isolation but it can also be found in longitudinal examinations and can therefore be considered as a stable, typical characteristic. These results lead to consequences for the planning and design of mathematics lessons based on a well-founded theory of cognition.