“Can any fraction be turned into a decimal?” A case study of a mathematical group discussion

This case study examines two days of teacher-led large group discussion in a fifth grade about a mathematical question intended to support student exploration of relationships among fraction and decimal representations and rational numbers. The purpose of the analysis is to illuminate the teacher’s work in supporting student thinking through the use of a mathematical question embedded in a position-driven discussion. The focus is an examination of the ways that the emergence of mathematical ideas is partially shaped by complex interactions among the mathematical contents of the question, the inherent properties of the discourse format and participant structure, and the available computational methods. The teacher’s work is conceptualized in terms of actions and practices that coordinate these diverse tools, in constant response to students’ concurrent use of them. This revised version was published online in July 2006 with corrections to the Cover Date.     

通用产品配置系统中的知识表示及应用

针对目前产品配置系统大多为面向单一产品的配置,开发通用产品配置系统,意在实现软件重用.该系统将知识表示运用于系统开发,通过知识编辑器、知识编译器和知识执行器,实现产品配置规则的自动判别和产品实例的自动检测,为实现产品配置的智能化提供可行的途径.     

Cultural diversity in science education through Novelization: Against the Epicization of science and cultural centralization

Science educators are confronted with the challenge to accommodate in their classes an increasing cultural and linguistic diversity that results from globalization. Challenged by the call to work towards valuing and keeping this diversity in the face of the canonical nature of school science discourse, we propose a new way of thinking about and investigating these problems. Drawing on the work of Mikhail Bakhtin, we articulate epicization and novelization as concepts that allow us to understand, respectively, the processes of (a) centralizing and homogenizing culture and language and (b) pluralizing culture and language. We present and analyze three examples that exhibit how existing mundane science education practices tend, by means of epicization, towards a unitary language and to cultural centralization. We then propose novelization as a way for thinking the opening up of science education by interacting with and incorporating alternative forms of knowing that arise from cultural diversity. © 2011 Wiley Periodicals, Inc. J Res Sci Teach 48: 824–847, 2011     

A further analysis of the ethics of representation in virtual reality: Multi-user environments

This is a follow-up article toPhilip Brey's ``The ethics of representation andaction in Virtual Reality' (published in thisjournal in January 1999). Brey's call for moreanalysis of ethical issues of virtual reality(VR) is continued by further analyzing issuesin a specialized domain of VR – namelymulti-user environments. Several elements ofBrey's article are critiqued in order to givemore context and a framework for discussion.Issues surrounding representations ofcharacters in multi-user virtual realities aresurveyed in order to focus attention on theimportance of additional discussion andanalysis of specialized aspects of VR.     

基于内容的图像检索高层语义处理方法

从图像语义层次描述方式、图像语义抽取方法两个方面对利用语义进行图像检索的研究状况进行总结,提出建立语义模板用于支撑高层语义检索,同时应用多层次的相关反馈方法建立和修正图像低层特征与高层语义间的联系,缩小图像检索过程中的“语义鸿沟”,达到一定程度语义检索的目的。     

Vicarious learning from dialogue and discourse

This study examined learning in the domain of sentence parsing and syntax treediagram construction. The aim of the study was to assess whether subjects could learn vicariously from recordings of interactions between a previous student and a tutor.Four intervention conditions and a control condition were compared. Subjects in a dialogue group (DL) read printed tutorial notes and subsequently vicariously viewed dynamic (animated) recordings of tree diagrams being constructed by a previous student in the presence of a tutor.The discourse (DI) condition was similar except that subjects viewed recordings of tree diagrams being constructed by a tutor who concurrently verbalised instructional discourse.In a third condition (DO), subjects viewed tree-diagram construction animation clips which were not annotated with either dialogue or discourse. In a linear text (LT) condition, subjects were given only printed tutorial notes. A control (CO) condition involved pre and post testing without any intervention.Results indicated that the dialogue condition was as effective as the discourse condition. This provides support for contention that re-usable dialogue is a useful resource for the vicarious learner. Another finding was that un-annotated animated diagrams were surprisingly effective. Several reasons for their effectiveness are suggested from the literature on instructional animations.     

德国语义学发展的历史趋势及其内在特征——逻辑实证主义之前语义学的诞生与兴起

19世纪到20世纪初是德国语义学诞生、发展和趋向转变的历史阶段,这一时期德国语义学的历史演进秉承了德国古典哲学传统尤其是康德哲学的思想精髓,从继承和批判的两个维度开启了向现代语义学迈进的崭新路径。在此过程中,语义学家们在新兴的精确性科学如数学和几何学发展的影响下,主张通过采用清晰而完善的逻辑语形构造,以保证语义理解的系统性和严密性;同时,心理学方法也开始和语义学的分析结合起来,形成了心理和意向语义分析的早期传统。在以逻辑实证主义为标志的德国现代语义理论兴起之前,它从哲学、心理学和语言科学等各个学科当中吸取营养、开辟阵地,为现代语义学的兴起和繁荣奠定了基础,其中所蕴含的心理意向分析和语境阐释等合理性思维成为了当代科学语义学建设的理论先驱和历史渊源。     

Constructivisms and Relativisms: A Shopper‘s Guide

Diverse forms of constructivism can be found in the literature today. They exhibit a commonality regarding certain classical positions that they oppose - a unity in their negative identities - but a sometimes wild multiplicity and incompatibility regarding the positive proposals that they put forward. In particular, some constructivisms propose an epistemological idealism, with a concomitant relativism, while others are explicitly opposed to such positions, and move in multifarious different directions. This is a potentially confusing situation, and has resulted in some critics branding all constructivisms with the charge of relativism, and throwing out the baby with the bath water. In addition, since the epistemological foundations of even non-relativist constructivisms are not as familiar as the classical positions, there is a risk of mis-interpretation of constructivisms and their consequences, even by some who endorse them, not to mention those who criticize. Because I urge that some version of constructivism is an epistemological necessity, this situation strikes me as seriously unfortunate for philosophy, and potentially dangerous for the practice of education.     

缺省模态逻辑

本文在Reiter 1980年提出的缺省逻辑的基础上,将缺省条件视为获取知识的背景知识与所得到的知识同等地加以考虑,提出了一种缺省模态逻辑。它是一种非单调逻辑,并且具有在Reiter的系统中所不能保证的两个重要性质:扩充的存在性和非单调性,然后通过知识从其背景中分离出来的方法,给出了一个缺省理论扩充的概念,它是Reiter的扩充概念的一种推广。     

论安·塞克斯顿诗歌《灰姑娘》中的重复

美国现代作家塞克斯顿在其诗歌《灰姑娘》中运用类像和怪异两种重复方式对原格林童话进行了成功的"变形",揭示了后现代社会的表征危机以及消费主义文化。