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931.
Ricardo?NemirovskyEmail author Cara?DiMattia Branca?Ribeiro Teresa?Lara-Meloy 《Journal of Mathematics Teacher Education》2005,8(5):363-392
This paper examines two types of discourse in which teachers engage when discussing case studies based on classroom episodes,
and the ways in which the availability of video data of these episodes may motivate a shift in the mode of discourse used.
We interviewed two pairs of secondary school mathematics teachers after they had read a case study based on a 16-minute mathematics
classroom episode taped in a secondary school in the United States. During each interview, a multimedia version of the case
study, including video of the original episode, was available to the participants. We identify two modes of discourse engaged
in by the teachers during the interviews: Grounded Narrative and Evaluative Discourse. We examine and identify the characteristics of the two discourse forms, drawn from both video and textual analysis. These
characteristics are self-reflective talk, perspective, ethics, and linguistic patterns. The identification of two modes of
discourse is relevant for researchers and teacher educators using case studies or video recordings. In addition, the findings
provide insight into how teachers are “seeing” classroom events in a video case study. 相似文献
932.
The construction of the cables is a key step for erecting suspen-dome structures. In practical engineering, it is difficult to ensure that the designed pre-stresses of cables have been exactly introduced into the structures in the site; so it is necessary to evaluate the influence of the variation of the pre-stresses on the structural behavior. In the present work, an orthogonal design method was employed to investigate the pre-stressed cables'sensitivity to the suspen-dome system. The investigation was concentrated on a Kiewitt suspen-dome. Parametric studies were carried out to study the sensitivity of the structure's static behavior, dynamic behavior, and buckling loads when the pre-stresses in the cables varied. The investigation indicated that suspen-dome structures are sensitive to the pre-stresses in all cables; and that the sensitivity depended on the location of the cables and the kind of structural behavior. Useful suggestions are given at the end of the paper. 相似文献
933.
Paul?Madgett Charles?H.?BelangerEmail author Joan?Mount 《Tertiary Education and Management》2005,11(4):337-354
The purpose of this paper is to investigate the integration between research findings produced at the University and Community
College levels and local SMEs (small and medium enterprises) as it impacts regional innovation systems and in particular the
prospect of cluster formation. The paper explores certain factors that have been identified in international literature as
being critical to fostering innovation in non-metropolitan regions. These factors include government policies and programmes,
internal and external infrastructure, partnership or research links among educational institutions, and support from local
business and civic leaders. Stakeholders from non-metropolitan regions were asked to judge the level of effectiveness with
reference to these development “factors” while highlighting weaknesses, strengths, and effects on innovation in their locale. 相似文献
934.
This research examined the typical flavor compounds in the commonest type of Khat called Harari Khat grown in the region of
Ethiopia. Twenty-eight compounds, which includes 1,2-Propanedione, 1-Phenyl, Hexanol, Hexanal compounds, Limonene, Benzaldehyde
with other flavors, were extracted by polydimethylsiloxane at room temperature for 30 min from Khat samples, and identified
by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). This method needs no organic solvents and
required minimal sample.
Project supported by scholarship from China 相似文献
935.
We report on stable individual differences in young yellow-crowned parakeets across 38 tasks of cognitive development on three scales involving object permanence, means-end relations, and spatial relations. Stable performance ranks on blocks of tasks emerged after 13 weeks in two groups of sibling parakeets, one hand-reared and the other parent-reared. Examination of subject characteristics, such as hatch order, sex, general activity level, avoidances, latencies, social status, and errors, showed no significant correlations with these performance ranks. Characteristic individual approaches to unstructured play activities (from a fourth scale) were consistent with individual behavioral differences seen on the structured cognitive tasks. 相似文献
936.
通过详实的资料 ,对综合理科课程的涵义、产生和发展、课程类型、教学目标、教学评价特征以及与分科理科课程和理科综合考试的关系进行了全面论证 ,从而澄清了当前对于综合理科认识的几个误区 相似文献
937.
Jing-Ru?WangEmail author 《International Journal of Science and Mathematics Education》2004,2(4):455-476
This article provides a model for the professional development of elementary science teachers. The model focused on integrating different domains of knowledge into science teaching, including the knowledge of the science curriculum, especially scientific inquiry, teachers knowledge, and students knowledge. The two case studies in this article revealed that the teachers construct their knowledge in a social context. The constant reflections on the experiences helped them to generate alternative teaching approaches. The findings suggest that the model of the project had two functions. First, it provides a useful strategy to help science teachers to bridge the gap between theories of teaching and their own teaching practices. Second, it provides a social learning environment for learning how to teach science. 相似文献
938.
This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was ob tained through orthogonal experiment. Properties of the enzyme membrane were investigated and compared with those of free enzyme and blank membrane. The thermal stability and pH stability of the enzyme inside the membrane were changed by immobilization. The optimum pH was found to be 6.0, which changes 1.0 unit compared with that of free acylase I. The optimum temperature was found to be about 90 ℃C, which is higher than that of free acylase I (60 ℃). Experimental results showed that immobilization had effects on the kinetic parameters of acylase I. 相似文献
939.
A Conceptual Framework for Assessing Motivation and Self-Regulated Learning in College Students 总被引:9,自引:0,他引:9
A conceptual framework for assessing student motivation and self-regulated learning in the college classroom is presented. The framework is based on a self-regulatory (SRL) perspective on student motivation and learning in contrast to a student approaches to learning (SAL) perspective. The differences between SRL and SAL approaches are discussed, as are the implications of the SRL conceptual framework for developing instruments to assess college student motivation and learning. The conceptual framework may be useful in guiding future research on college student motivation and learning. 相似文献
940.
The paper is a reflective account of the design and implementation of mathematical tasks that evoke uncertainty for the learner.
Three types of uncertainty associated with mathematical tasks are discussed and illustrated: competing claims, unknown path or questionable conclusion, and non-readily verifiable outcomes. One task is presented in depth, pointing to the dynamic nature of task design, and the added value stimulated by the uncertainty
component entailed in the task in terms of mathematical and pedagogical musing. 相似文献