Communication systems simulator with error correcting codes using MATLAB

In this work, the characteristics of a simulator for channel coding techniques used in communication systems, are described. This software has been designed for engineering students in order to facilitate the understanding of how the error correcting codes work. To help students understand easily the concepts related to these kinds of codes, a user-friendly interface has been developed using the MATLAB environment, since it provides many toolboxes related to communication systems.     

Error correcting codes

Linear algebraic codes are an elegant illustration of the power of Algebra. We introduce linear codes, and try to explain how the structure present in these codes permits easy implementation of encoding and decoding schemes.     

Error correcting codes

In the first article of this series we showed how redundancy introduced into a message transmitted over a noisy channel could improve the reliability of transmission. In this article we describe one of the earliest linear codes invented for this purpose, and show how the algebraic structure of the code enables easy decoding.     

Error correcting codes

Reed Solomon codes began as mathematical curiosities; today they are perhaps the most practical and widely used codes. This article describes the ingenious application of these codes to error correction in Compact Disc audio systems.     

The reality and potential of correcting pupils' work in mathematics

Resumé Par un survol des pratiques et des effets de la correction des devoirs, on voit que l'on peut en attendre, dans l'état actuel des choses, au mieux une relative neutralité, mais, d'une manière générale, des effets plutôt négatifs. Aucune des propositions sur lesquelles s'appuie implicitement et explicitement l'entreprise de correction n'est vraie. Mais les analyses faites, au lieu d'avoir pour corollaire la constation de la non prise en compte des élèves dans leur logique de réponses et de questions, pourraient constituer un enseignement pour les professeurs, et donc pour les élèves.

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The reality and potential of correcting pupils' work in mathematics

Reflecting on teachers' practice in correcting pupils' work in mathematics, we find that at present we can expect at best a limited neutrality, but in general a more negative stance. None of the principles, implicit or explicit, on which the process of correction is based, is valid. But rather than simply drawing from the analysis the conclusion that the logic of pupils' answers and questions is ignored, the evidence might be far more instructive for the teachers themselves, and ultimately for their pupils.

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J'ai analysé un nombre considérable d'erreurs avec leurs corrections dans le courant de trois ouvrages cités en bibliographie ci-dessous. Dans le ler, on se réfère ici plus particulièrement au chapitre 5. Le dernier ouvrage, comme son sous-titre l'indique (et à propos de la note, pages 224 à 253), a plus particulièrement comme sujet la significatíon des erreurs, et la nécessité qu'il y a à s'en servir dans l'enseignement si on le veut efficace.     

量子力学中的完全性关系在数学和色度学中的应用

本文运用量子力学中的完全性关系分析了数学中整数的构成和色度学中颜色的合成问题,证明了完全性关系在其它领域也有着广泛的应用,从而有助于进一步研究数的构成和线性展开以及颜色、光谱的合成和分解问题．     

CH376纠正机器视觉提取螺孔误差的方法

基于对工件螺孔形态的观察,分析了DXF格式的工件图纸文件,研究了文件管理控制芯片CH376的应用实例,提出了一种能有效纠正视觉误差、提高螺孔识别精度的方法。首先,将机器视觉技术与CAD技术相结合,在视觉识别的基础上,使用CH376枚举出用户U盘内的DXF文件,并根据DXF文件的构成规律查找出指定字段中的图元信息。然后,控制器利用图元依附关系、螺孔形状、螺钉国标规格等判定条件筛选出符合要求的坐标数据作为视觉误差纠正基准。最后,结合视觉与图纸数据,对实际工件中存在的平移偏差和旋转偏差进行纠正,演算出现场工件的正确螺孔坐标数据。实验结果表明,所提方法能够有效纠正视觉识别误差,且识别过程无需人工参与,工作速率和成功率均有明显提高。     

高等数学思想在初等数学中的渗透

本文通过笔者的教学实践,对高等数学方法在初等数学的渗透作系统总结,突出高观点下的数学教学的理念。     

人教版小学数学教材中蕴含的数学文化

文章探讨人教版小学数学教材中蕴含的数学文化,主要从数学家的故事、数学发展史、中国古代典籍《九章算术》、数学的广泛应用这四个方面来阐述。     

数学的本质

本文从数的概念起源、数的基础运算和数学的基本特征等方面来解析数学的本质。数的概念来自理性的抽象,现实中来源于可替代物。基础运算中加法是母法则,减法是唯一的分析判断,加减反映了量的连续性。而乘除反映了量的间断性。乘除的二次抽象性无法反映不确定性关系。数学创造力与艺术创造力完全不同。数学演绎中的理性盲点需要经验来弥补。     

Dealing with errors in mathematics classrooms: Structure and relevance of perceived error climate

Errors are often perceived by students as self-threatening and not as learning opportunities. The present work focuses on contextual influences on reactions to errors and learning processes. Based on prior research, a conceptualization of perceived error climate in the classroom with eight subdimensions and one superordinate uniform factor is proposed and a newly developed student questionnaire for its assessment is presented. Results of a study with N = 1116 students from 56 mathematics classrooms in German secondary schools indicated the validity of the error climate conceptualization and the suitability of the questionnaire. Moreover, the results showed that perceived error climate in the classroom predicted the adaptivity of students’ individual reactions to errors above and beyond perceived classroom goal structures and personal achievement motivation (academic self-concept, mastery goal orientation). In addition, the study provided evidence that perceived error climate affects – partially mediated through students’ individual reactions to errors – the quantity and self-regulation of students’ effort.     

数学中的美学教学

数学美是数学发展的内在驱动力之一,也是评价数学理论的重要标准之一。本文结合大学数学内容,对数学美进行了浅析。主要揭示了在大学数学课程的相关知识中所蕴藏出来的美的现象,美的规律。数学美作为科学美的一种,它即具有美的共性,更具有独特的个性,它的内容是极其丰富的。我们可以从数学图形,公式,定理,方法中感受的人类智慧的魅力,感受这种美。最后阐述了在数学教学中对数学美教学的重要性。     

小学数学教学中人文数学的实施策略

在数学教育中渗透人文教育,弘扬人文精神,是素质教育的要求,是我国新课程改革所规定的数学教育的目的,更是数学教育发展的必然。人文数学是数学与人文的结合,是用数学的精神、原则、思想和方法对学生进行文化陶冶和人格塑造,让数学教育在传授科学的同时起到提高人的文化素养和教化人格的作用。教育者可从创设特色人文课堂情境、引导学生自主学习、重视学生的个体差异三个方面实现人文教育在数学教学中的渗透,进而实现科学与人文在数学教学中有机的结合,进而促进学生人文素养的提升。     

数学美与数学美学教育探讨

许多哲学家认为,每一完备的科学理论应该具有简洁、和谐、对称、统一等美学特征.从这个意义来看,数学是一门美学!因为它不但具有抽象性、逻辑性、严密性特征,更具有美学特点.数学美蕴藏在它所特有的抽象符号、严格的语言及演绎体系中.因此,在数学教学中同样可以进行美学教育.本文从数学美及数学美学教育两方面作一些探讨,以期与同行切磋.     

论数学概念的教学

在数学学习中，数学概念不清，学生在进行计算，证明，交流、推理时都会出现极大困难，然而，由于不少学生在以抽象思维能力为主的数学能力等诸多因素上的差异，导致了数学概念这个重点同时又成了数学教学的难点，本文从探讨数学概念教学困难的原因，数学概念的学习机制入手，为的是找出更加有效的教学策略，以促进数学课堂教学改革，实现高效教学。     

评价对价值观的修正作用

评价分为道德评价、审美评价和功利评价.评价是进行思想教育工作的重要途径和手段.     

The relationship of teachers' conceptions of mathematics and mathematics teaching to instructional practice

Case studies were conducted to investigate the conceptions of mathematics and mathematics teaching held by three junior high school teachers. Examination of the relationship between conceptions and practice showed that the teachers' beliefs, views, and preferences about mathematics and its teaching played a significant, albeit subtle, role in shaping their instructional behavior. Differences among the teachers in their conceptions and practices are explained followed by a discussion of properties of their conceptual systems.This paper is based on the author's doctoral dissertation which was directed by Professor Thomas J. Cooney of the University of Georgia and was partly supported by a grant from San Diego State University. I wish to express my appreciation to the teachers who participated in the study and their administrators.     

高职数学课程体系改革探索

培养具有创新精神与创造能力的高素质人才,全面提高学生的数学素质,切实加强应用数学的意识,构建数学系列课程中各门课程的结构、比例,达到知识结构合理、能力水平增加、综合素质提高的目的,以适应21世纪对各类人才的数学素质的要求.