Differences among fastball,curveball, and change-up pitching biomechanics across various levels of baseball     

Glenn S. Fleisig  Walter A. Laughlin  Kyle T. Aune  E. Lyle Cain  Jeffrey R. Dugas  James R. Andrews 《Sports biomechanics / International Society of Biomechanics in Sports》2016,15(2):128-138

Controversy continues whether curveballs are stressful for young baseball pitchers. Furthermore, it is unproven whether professional baseball pitchers have fewer kinematic differences between fastballs and off-speed pitches than lower level pitchers. Kinematic and kinetic data were measured for 111 healthy baseball pitchers (26 youth, 21 high school, 20 collegiate, 26 minor league, and 18 major league level) throwing fastballs, curveballs, and change-ups in an indoor biomechanics laboratory with a high-speed, automated digitising system. Differences between pitch types and between competition levels were analysed with repeated measures ANOVA. Shoulder and elbow kinetics were greater in fastballs than in change-ups, while curveball kinetics were not different from the other two types of pitches. Kinematic angles at the instant of ball release varied between pitch types, while kinematic angles at the instant of lead foot contact varied between competition levels. There were no significant interactions between pitch type and competition level, meaning that kinetic and kinematic differences between pitch types did not vary by competition level. Like previous investigations, this study did not support the theory that curveballs are relatively more stressful for young pitchers. Although pitchers desire consistent kinematics, there were differences between pitch types, independent of competition level.  相似文献   

John J. Laukaitis. Community Self‐Determination: American Indian Education in Chicago, 1952–2006. Albany: State University of New York Press, 2015. 282 pp. Hardcover $85.00.     

Kyle T. Mays 《History of education quarterly》2016,56(4):669-673

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The Effect of Randomized Homework Contingencies on College Students' Daily Homework and Unit Exam Performance     

Charles E. Galyon  Kyle L. Voils  Carolyn A. Blondin  Robert L. Williams 《Innovative Higher Education》2015,40(1):63-77

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Why action research? An emergent role in educational reform     

Ric A. Hovda  Diane W. Kyle 《Irish Educational Studies》2013,32(2):24-44

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Who's Afraid of the Big Black Man?     

Jason Kyle Johnson 《Educational Studies A Journal of the American Educational Studies Association》2018,54(2):229-236

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Attitudes of Alaskan distance education students toward media and instruction     

Kyle Franks 《The American journal of distance education》2013,27(3):60-71

Abstract

This article reports the results of a study to assess the attitudes of distance higher education students in various units of the College of Rural Alaska, University of Alaska, Fairbanks. Emphasis was given to media preferences, the convenience of various media, and overall attitudes toward distance instruction. Results of a mail survey indicated acceptance of a wide variety of media as well as strong general support for distance instruction. Additionally, a large majority of respondents rated distance instruction as equal to or better than face‐to‐face instruction.  相似文献   

Putting the computer in its place: a study of teaching with technology     

Susan S. Stodolsky  Teresa L. Ferguson  Karen Wimpelberg 《课程研究杂志》2013,45(2):121-130

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R. Wegerif and L. Dawes, Thinking and Learning with ICT: Raising Achievement in Primary Classrooms (2004) ISBN 0-415-30475-X More information on the associated website .     

Rebecca Ferguson   《Thinking Skills and Creativity》2007,2(2):149-150

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The Audience and Business of YouTube and Online Videos     

Douglas A. Ferguson 《广播与电子媒介杂志》2013,57(4):717-718

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The benefits and costs of web surfing     

Elizabeth M. Perse  Douglas A. Ferguson 《Communication quarterly》2013,61(4):343-359

Although the Web audience is growing exponentially, little research has explored the benefits that the audience derives from their use of the Web. This study took a cost‐benefit approach to exploring the specific benefits and opportunity costs associated with World Wide Web use. We hypothesized that greater benefits coupled with fewer opportunity costs (e.g., computer and Internet access, computer expertise, connection speed, effort, and multimedia) would have an impact on the amount of time people spend on the Web and the value they attach to their Web use. We conducted a Web‐based survey of 250 students enrolled at two “wired” universities who were required to use the Web for coursework. The results revealed that Learning was the most salient benefit of the Web, followed by Pass Time and Entertainment. We found some support for the impact of opportunity costs on Web use. Stronger support was found for the impact of benefits and costs on Web surfing value. We also found that Entertainment and sports Web sites were the ones most likely to be linked to beneficial Web use. The discussion relates the results of the study to speculations about the future of the Web audience and the impact of reduced opportunity costs on Web use.  相似文献