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211.
Measuring perceived social presence in distributed learning groups   总被引:1,自引:0,他引:1  
Social presence—the degree to which ‘the other’ in a communication appears to be a ‘real’ person—has captured the attention of those dealing with learning in groups through computer-supported collaborative learning environments. The concept is important because it affects participation and social interaction, both necessary for effective collaboration and knowledge construction. This article reports on the construction and validation of a self-reporting (Dutch-language) Social Presence Scale to determine perceived social presence in distributed learning groups using computer-supported collaborative learning environments. The result is a one-dimensional scale consisting of five items with an internal consistency of .81. We used a nomological network of similar constructs for further validation. The findings suggest that the Social Presence Scale has potential to be useful as a measure for social presence.  相似文献   
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The effectiveness of an explicit, systematic reading intervention for first-grade students whose home language was Spanish and who were at risk for reading difficulties was examined. Participants were 69 students in 20 classrooms in 7 schools from 3 districts who initially did not pass the screening in Spanish and were randomly assigned within schools to a treatment or comparison group; after 7 months, 64 students remained in the study. The intervention matched the language of instruction of their core reading program (Spanish). Treatment groups of 3 to 5 students met daily for 50 min and were provided systematic and explicit instruction in oral language and reading by trained bilingual intervention teachers. Comparison students received the school's standard intervention for struggling readers. Observations during core reading instruction provided information about the reading instruction and language use of the teachers. There were no differences between the treatment and comparison groups in either Spanish or English on any measures at pretest, but there were significant posttest differences in favor of the treatment group for the following outcomes in Spanish: Letter-Sound Identification (d = 0.72), Phonological Awareness composite (d = 0.73), Woodcock Language Proficiency Battery-Revised Oral Language composite (d = 0.35), Word Attack (d = 0.85), Passage Comprehension (d = 0.55), and two measures of reading fluency (d = 0.58-0.75).  相似文献   
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The purpose of this study was to examine the reliability and validity of scores from six early literacy probes developed for use with preschool‐age children. The literacy probes were administered to 84 preschoolers at three time points over a 6‐month period. Also, a criterion measure of early literacy skills was administered to a subset of students. Results indicated that the probes demonstrate adequate reliability for screening decisions, moderate to strong concurrent relationships with a criterion measure, and developmentally appropriate changes in children's early literacy skills over time. These results add to the growing body of evidence supporting the technical adequacy of general outcome measurement for use in monitoring the progress of preschoolers' academic skill development. © 2009 Wiley Periodicals, Inc.  相似文献   
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An hybrid uninterrupted multi-speed transmission (HUMST), based on the integration of a planetary gear set and a 3-speed automatic manual transmission (3-AMT), is developed to satisfy the specific performance indexes of mining trucks. The power-split device can alleviate and eliminate the inherent torque interruption of the 3-AMT during gear shift by implementing the designed cooperative shift control strategy which is optimized by quadratic performance index. In order to achieve fast torque coordination while guaranteeing the driving comfort performance, the torque profiles of the power split device and the traction motor are optimized by Linear-quadratic regulator (LQR) algorithm. Dynamic programming (DP) is implemented as a benchmark to demonstrate the maximum fuel efficiency of the proposed HUMST. Because of the high computational cost of optimal control strategies such as DP, an improved real-time control strategy (IRTCS) using modified Gaussian distribution function is proposed to significantly reduce the computing load. As efficiency-oriented energy control strategy would result in frequent gear shifts, to achieve a desirable tradeoff between the overall efficiency and the shift stability, multi-objective genetic algorithm (MGA) is integrated to optimize the overall performance. The detail mathematical and dynamic model shows that the proposed shifting strategy with LQR can effectively suppress shift jerk, and the proposed IRTCS with MGA can reduce shift frequency by 70.78% to improve the drivability, only sacrificing 4.86% of overall efficiency compared to that of DP.  相似文献   
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Universities aspire to offer students a transformative experience, but rarely spell out the nature of this transformation. In this essay, L. A. Paul and John Quiggin frame the successful university education as transformative in the philosophical sense. They explain the way that a successful college education can be understood as generating an individual conceptual revolution, and thus, as a transformative experience. Education can create epistemically transformative change through the process of developing critical thinking skills, leading to conceptual replacement and the discovery of new intellectual frameworks. This epistemic transformation, if deep enough, scales up into a personal transformation. After explicating the nature and structure of transformative education, Paul and Quiggin show how understanding transformation in terms of personal change and awareness of unawareness clarifies the debate over its value.  相似文献   
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