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921.
922.
The main purpose of this paper is to demonstrate how to apply the Hierarchical Linear Modeling (HLM) technique to multi-wave Curriculum-Based Measurement (CBM) measures in modeling academic growth and assessing its relations to student- and instruction-related variables. HLM has advantages over other statistical methods (e.g., repeated measures ANOVA, Structural Equation Modeling) in modeling academic growth. The advantages include allowing more flexible research designs in collecting multiple data points and estimating growth rates and their relations to correlates in more reliable, accurate ways. CBM, as a multi-wave progressmonitoring system, also has distinctive psychometric features that facilitate longitudinal research on academic skill development. These features include provision of multiple data points within short time periods, good validity and reliability, and sensitivity for detecting small degrees of change. Finally, research questions related to assessing the academic growth of students with learning difficulties and using assessment results to improve educational practices for them are discussed  相似文献   
923.
INTRODUCTION Recently, a new type of artificial compositematerials (so-called left-handed media or negativerefractive index media) whose electric permittivityand magnetic permeability are simultaneouslynegative (corresponding to a negative refractiveindex) over a certain frequency band has attractedconsiderable attention due to its extraordinaryelectromagnetic properties (Pendry, 2000; Shelbyet al., 2001; Grbic and Eleftheriades, 2004; Chen eal., 2004). The negative refractive inde…  相似文献   
924.
The aim of this study is to design and implement a digital interactive globe system (DIGS), by integrating low-cost equipment to make DIGS cost-effective. DIGS includes a data processing unit, a wireless control unit, an image-capturing unit, a laser emission unit, and a three-dimensional hemispheric body-imaging screen. A quasi-experimental study was conducted to evaluate the learning effectiveness of our system. A total of 105 junior high-school students from Taiwan participated in this 8-week experiment. The students were divided into three individual groups of 35 students each, with one control group and two experimental groups (EG1 and EG2). The results of one-way mixed design ANOVA indicated that participants in the experimental group, who used the DIGS, outperformed the other two groups, in the post-test as well as in the delayed test. These findings demonstrate that the proposed DIGS can effectively enhance the performance of the learners in an Earth Science course.  相似文献   
925.
Nonsocial play continues to be perceived as a behavior that is detrimental young children’s development. The research evidence in this area is mixed but lends itself to a more positive view of nonsocial play. Despite the substantial amount of literature available, the terminology used fails to be consistent and may prove to be distracting and confusing to practitioners and caregivers. This paper reviews the current literature on young children’s nonsocial play. Distinctions among different types of nonsocial play are identified, as well as some reasons children engage in these activities. By developing a better understanding of the role of nonsocial play in early childhood, caregivers may better understand when children need their help in promoting more social types of play and when intervention may or may not be necessary.  相似文献   
926.

Authors Index

Authors Index, Volume 23 (2001)  相似文献   
927.
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   
928.
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   
929.
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   
930.
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   
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