Is passive drag dependent on the interaction of kayak design and paddler weight in flat-water kayaking?     

Beatriz B. Gomes  Filipe A.V. Conceição  David R. Pendergast  Ross H. Sanders  Mário A.P. Vaz  João Paulo Vilas-Boas 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):394-403

Abstract

Drag is one of the major factors that influences kayaking performance. To focus on the drag of the kayak’s hull shape and the paddlers’ weight per se, the passive drag (D_p) was measured on a flat-water sprint course for one paddler with added weights. D_p was measured by an electromechanical towing device using a load cell, at incremental and constant velocities from 2.78 to 5.56 m/s. Three kayaks of different sizes and shapes (Nelo® K1 Quattro-M, ML, and L) were used and the paddlers’ body weight was adjusted with weights so the total paddler weight in the kayak was 65, 75, and 85 kg. The mean D_p increased by the power function of D = kvⁿ (mean R² = .990; SD .006). The D_p went from 21.37?±?1.29 N at 2.78 m/s to 89.32?±?6.43 N at 5.56 m/s. For the two lighter weighted kayaks (65 and 75 kg), the lowest D_p was observed with different kayak sizes (M, ML, or L) depending on the target velocity. The manufacturers suggest that paddlers should select a kayak size according to their body weight to minimise drag; however, the results of this study suggest that target velocities, and thus competition distance should also be factored into kayak selection.  相似文献   

Training priority: Positive suggestions     

Jo Kuykendall 《Early Childhood Education Journal》1992,19(4):25-27

“Keep the sand low, Mike, so it doesn't accidentally get in someone's eyes. That would hurt. Yes, like that — you and Jonathan are building some very long roads. Would a little water help you pack them smoothly?” This teacher's tone of voice is accepting, and her words show understanding of the lifelong learning process.  相似文献   

Validation and profile of Chinese pre-service teachers’ technological pedagogical content knowledge scale     

Guoyuan Sang  Jo Tondeur  Ching Sing Chai 《Asia-Pacific Journal of Teacher Education》2016,44(1):49-65

Researchers state that teachers in different contexts reported different technological pedagogical content knowledge (TPACK). This phenomenon may partially be explained by cultural differences. Based on this consideration, the development and validation of the Chinese pre-service teachers’ technological pedagogical content knowledge (CTPCK) scale is described in this article. The sample was split into two subsamples on random basis (n1 = 229, n2 = 207) for the purpose of conducting (1) exploratory factor analysis (EFA) and (2) confirmatory factor analysis (CFA), respectively. After the EFA, the CTPCK scale excluded six items and included eight factors with 42 items. Reliability and correlations were discussed. The findings revealed that the CTPCK scale was a valid and reliable instrument for measuring the TPACK of Chinese pre-service teachers’ knowledge with or without linking educational technology.  相似文献   

Essential Conditions for Technology-Supported,Student-Centered Learning: An Analysis of Student Experiences With Math Out Loud Using the ISTE Standards for Students     

Mary Jo Dondlinger  Julie McLeod  Sheri Vasinda 《Journal of Research on Technology in Education》2016,48(4):258-273

This article explores links between student experiences with technology-rich mathematics instruction and the ISTE Standards for Students. Research methods applied constructivist grounded theory to analyze data from student interviews against the ISTE Standards for Students to identify which elements of the design of this learning environment seemed to support the attainment of both mathematics content objectives and the ISTE Standards for Students. Researchers then identify guiding principles for the effective design of technology-supported, student-centered learning environments based on analysis of the results. (Keywords: ISTE standards, mathematics education, student- created work, technology-rich learning)  相似文献   

Volume contents     

Jo Boaler 《Educational Studies in Mathematics》2002,50(3):347-348

Volume Contents

Volume contents  相似文献   

Attitude items and low ability students: the need for a cautious approach to interpretation     

Michela Gnaldi  Ian Schagen    Jo Morrison 《Educational studies》2005,31(2):103-113

The results of the Progress in International Reading Literacy Study (PIRLS 2001) were published in 2003. In addition to data about the reading achievements of 10‐year‐olds in 35 countries, PIRLS 2001 also collected questionnaire information from children, their teachers, headteachers and parents. The results showed not just how well students can perform in various reading tasks, but also the relationship between reading abilities and other characteristics, including the characteristics of their homes and schools, the students' attitudes to reading, reading enjoyment, self‐confidence, engagement and perceptions of their reading abilities. Surprisingly enough, children in England were reported as having poor attitudes to reading, compared to children in many other countries, despite high achievement on the reading tests. This paper raises some concerns about the interpretation of results from the study, suggesting a more complex picture than that presented in the summary index published in 2003. Our secondary analysis of the attitude and achievement data from PIRLS shows that pupils with low ability levels have misunderstood the questions which tested their attitudes towards reading. The authors point out that caution is needed when making cross‐country comparisons to avoid naïve approaches to interpretation.  相似文献   

Delivering NEET policy packages? A decade of NEET policy in England     

Jo Hutchinson  Vanessa Beck  Tristram Hooley 《Journal of Education & Work》2016,29(6):707-727

This article explores the way in which government policy shapes the lives of young people who are not in education, employment or training (NEET). In particular it examines how the concept of NEETs is set within a specific infrastructure and discourse for managing and supporting young people. The article provides a brief history of the NEET concept and NEET initiatives, before moving on to scrutinise the policies of the Coalition Government. A key distinction is made between those policies and practices that seek to prevent young people becoming NEET from those that seek to re-engage those who are NEET. It is argued that the Coalition has drawn on a similar active labour market toolkit to the previous Labour administration, but that this has been implemented with fewer resources and less co-ordination. It concludes that there is little reason to believe that Coalition policy will be any more successful than that of the previous government, and some reason to be concerned that it will lead to young people becoming more entrenched within NEET.  相似文献   

Effects of learning analytics dashboard: analyzing the relations among dashboard utilization,satisfaction, and learning achievement     

Jeonghyun Kim  Il-Hyun Jo  Yeonjeong Park 《Asia Pacific Education Review》2016,17(1):13-24

The learning analytics dashboard (LAD) is a newly developed learning support tool for virtual classrooms that is believed to allow students to review their online learning behavior patterns intuitively through the provision of visual information. The purpose of this study was to empirically validate the effects of LAD. An experimental study was conducted with a dashboard treatment group and a control group. The researchers developed a LAD and evaluated its effectiveness on the sample of 151 college students at a private university located in Korea, who were taking the online course titled “Management Statistics” in the first semester of 2014. The following results were obtained. First, the students who received dashboard treatment presented higher final score than those who did not. Second, the dashboard usage frequency, as measured by the number of times the dashboard was opened, did not have a significant impact on learning achievement. However, a slightly positive correlation between satisfaction with LAD and learning achievement was observed. Further analysis indicated that learners who used the dashboard only a few times showed relatively high satisfaction with LAD. On the other hand, high academic achievers who opened LAD relatively frequently showed lower satisfaction with dashboard. The results guide that LAD should be revised in a way to motivate learners consistently and support learners who have different academic achievement levels. The study discusses the further research tasks in terms of LAD development as an effective and personalized feedback tool to improve learners’ academic achievement.  相似文献   

Approaches to Teacher Professional Development: a critical appraisal*     

João M. Moreira 《欧洲师范教育杂志》1996,19(1):47-63

  相似文献   

For the children ... we'll work together     

Jo Kuykendall 《Early Childhood Education Journal》1989,16(3):38-39

Jo Kuykendall teaches with the University of Alaska, Fairbanks; and is a consultant with CARE (Child Care Administration, Regulation and Education) Specialists. This is an adaptation of the poem presented at the closing ceremony for the Alaska ECE Conference in Fairbanks, February, 1987.  相似文献