Validation of a videogrammetry technique for analysing American football helmet kinematics     

Ann Bailey  James Funk  David Lessley  Chris Sherwood  Jeff Crandall  William Neale 《Sports biomechanics / International Society of Biomechanics in Sports》2020,19(5):678-700

ABSTRACT

Professional American football games are recorded in digital video with multiple cameras, often at high resolution and high frame rates. The purpose of this study was to evaluate the accuracy of a videogrammetry technique to calculate translational and rotational helmet velocity before, during and after a helmet impact. In total, 10 football impacts were staged in a National Football League (NFL) stadium by propelling helmeted 50th percentile male crash test dummies into each other or the ground at speeds and orientations representative of concussive impacts for NFL players. The tests were recorded by experienced sports film crews to obtain video coverage and quality typically available for NFL games. A videogrammetry procedure was used to track the position and rotation of the helmet throughout the relevant time interval of the head impact. Compared with rigidly mounted retroreflective marker three dimensional (3-D) motion tracking that was concurrently collected in the experiments, videogrammetry accurately calculated changes in translational and rotational velocity of the helmet using high frame rate (two cameras at 240 Hz) video (7% and 15% error, respectively). Low frame rate (2 cameras at 60 Hz) video was adequate for calculating pre-impact translational velocity but not for calculating the translational or rotational velocity change of the helmet during impact.  相似文献   

Assessing volunteer satisfaction at the London Olympic Games and its impact on future volunteer behaviour     

Minhong Kim  Steven Suk-Kyu Kim  May Kim  James J. Zhang 《Sport in Society》2019,22(11):1864-1881

Abstract

In recent years, volunteering has received strong research attention from both scholars and practitioners. For the most part, involvement in volunteer activities has been identified as an important determinant of future volunteering. Through revalidating an existing instrument, the purpose of this study was to assess the dimensions of volunteer satisfaction at the 2012 London Olympic Games and its impact on future volunteer behaviour. The findings of this study shed light on the identification of volunteer satisfaction factors in the mega sporting event setting, particularly for a unique type of volunteer (i.e. media worker) assigned to a special set of tasks. Unlike Galindo-Kuhn and Guzley’s results that revealed participation efficacy and group integration to be strong predictors of volunteer satisfaction, organizational support was the primary predictor for media centre volunteers’ re-participation intention towards future volunteering programmes.  相似文献   

Guiding Low Spatial Ability Individuals through Visual Cueing: The Dual Importance of Where and When to Look     

Victoria A. Roach  Graham M. Fraser  James H. Kryklywy  Derek G.V. Mitchell  Timothy D. Wilson 《Anatomical sciences education》2019,12(1):32-42

Research suggests that spatial ability may predict success in complex disciplines including anatomy, where mastery requires a firm understanding of the intricate relationships occurring along the course of veins, arteries, and nerves, as they traverse through and around bones, muscles, and organs. Debate exists on the malleability of spatial ability, and some suggest that spatial ability can be enhanced through training. It is hypothesized that spatial ability can be trained in low-performing individuals through visual guidance. To address this, training was completed through a visual guidance protocol. This protocol was based on eye-movement patterns of high-performing individuals, collected via eye-tracking as they completed an Electronic Mental Rotations Test (EMRT). The effects of guidance were evaluated using 33 individuals with low mental rotation ability, in a counterbalanced crossover design. Individuals were placed in one of two treatment groups (late or early guidance) and completed both a guided, and an unguided EMRT. A third group (no guidance/control) completed two unguided EMRTs. All groups demonstrated an increase in EMRT scores on their second test (P < 0.001); however, an interaction was observed between treatment and test iteration (P = 0.024). The effect of guidance on scores was contingent on when the guidance was applied. When guidance was applied early, scores were significantly greater than expected (P = 0.028). These findings suggest that by guiding individuals with low mental rotation ability “where” to look early in training, better search approaches may be adopted, yielding improvements in spatial reasoning scores. It is proposed that visual guidance may be applied in spatial fields, such as STEMM (science, technology, engineering, mathematics and medicine), surgery, and anatomy to improve student's interpretation of visual content. Anat Sci Educ. © 2018 American Association of Anatomists.  相似文献   

Important Considerations for Assessment to Function in the Service of Education     

James W. Pellegrino 《Educational Measurement》2020,39(3):81-85

Professor Gordon argues for a significant reorientation in the focus and impact of assessment in education. For the types of assessment activities that he advocates to prosper and positively impact education, serious attention must be paid to two important topics: (1) the conceptual underpinnings of the assessment practices we develop and use to support learning and instruction, and (2) the arguments and evidence we establish for their validity given the intended interpretive use. Such a focus highlights fundamental concepts that have long existed in the broader assessment literature – carefully defining and operationalizing our constructs and then validating the assessments of those constructs. What differs now are the conceptual frameworks, briefly outlined here, that can and must be used to guide both aspects of such work.  相似文献   

Editorial     

James Williams 《Quality in Higher Education》2019,25(1):1-3

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Coordinating scaffolds for collaborative inquiry in a game-based learning environment     

Asmalina Saleh  Chen Yuxin  Cindy E. Hmelo-Silver  Krista D. Glazewski  Bradford W. Mott  James C. Lester 《科学教学研究杂志》2020,57(9):1490-1518

Collaborative inquiry learning affords educators a context within which to support understanding of scientific practices, disciplinary core ideas, and crosscutting concepts. One approach to supporting collaborative science inquiry is through problem-based learning (PBL). However, there are two key challenges in scaffolding collaborative inquiry learning in technology rich environments. First, it is unclear how we might understand the impact of scaffolds that address multiple functions (e.g., to support inquiry and argumentation). Second, scaffolds take different forms, further complicating how to coordinate the forms and functions of scaffolds to support effective collaborative inquiry. To address these issues, we identify two functions that needed to be scaffolded, the PBL inquiry cycle and accountable talk. We then designed predefined hard scaffolds and just-in-time soft scaffolds that target the regulation of collaborative inquiry processes and accountable talk. Drawing on a mixed method approach, we examine how middle school students from a rural school engaged with Crystal Island: EcoJourneys for two weeks (N=45). Findings indicate that hard scaffolds targeting the PBL inquiry process and soft scaffolds that targeted accountable talk fostered engagement in these processes. Although the one-to-one mapping between form and function generated positive results, additional soft scaffolds were also needed for effective engagement in collaborative inquiry and that these soft scaffolds were often contingent on hard scaffolds. Our findings have implications for how we might design the form of scaffolds across multiple functions in game-based learning environments.  相似文献   

Developing higher-order reading skills in mainstream primary schools: A metacognitive and self-regulatory approach     

Taryn Moir  James Boyle  Lisa M. Woolfson 《British Educational Research Journal》2020,46(2):399-420

The ability to read relies upon not just decoding, but also comprehending text. Being a good comprehender requires strategic reading and implies the use of comprehension strategies. Research indicates that readers who are taught several reading comprehension strategies have better reading skills than those only taught a single strategy. One multiple strategy reading comprehension intervention was evaluated using a mixed-model quasi-experimental design. Intervention and control conditions groups were assessed at pre- and post-test points with standardised reading comprehension abilities, measured as the primary outcome measure. Implementation science principles were observed and evaluated. The schools all served areas of low socio-economic status. 74 pupils (aged 9–10) in five classes in four primary-level mainstream schools in a Scottish local authority were recruited as participants. Training was provided to participating schools by the first author and the programme was delivered in four sessions of 45 minutes per week for 8 weeks. An ANCOVA revealed a statistically significant effect of condition. Statistically significant scores were also evident in the secondary outcome measures of decoding of target word skills, children’s self-reports of their reading strategy use and recreational reading frequency. Implementation tools indicated that the intervention was acceptable and feasible to implement. Implications of introducing this multiple strategy reading comprehension programme and of the evaluation of implementation are discussed.  相似文献   

Humankind,human nature,and misanthropy     

Kidd  Ian James 《Metascience》2020,29(3):505-508

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Transforming in the visiting assistant professor role: collaborative self-study research in physical education teacher education     

James D. Ressler  K. Andrew R. Richards 《Sport, Education and Society》2019,24(5):507-519

Transitioning into faculty roles can be a challenging experience. Responsibilities related to teaching, research, and service can be difficult to balance, and mismatch between personal preferences for work focus and instructional expectations can be problematic. This is particularly true of visiting assistant professors who want to work toward tenure-track positions, but whose current job focus is on teaching. Through transformative learning theory and employing the methodologies of self-study, we sought to understand the experiences of Kevin, the second author and a first-year visiting assistant professor. We draw data from Kevin's reflective journal and discussions between Kevin and his critical friend, Jim. Themes included (a) becoming an academic, (b) a hard-wired disposition toward work, and (c) influence of the VAP on emotional and personal health. Results are discussed through the lens of transformative learning theory and focus on Kevin's growth during his year as a visiting assistant professor.  相似文献   

Efficacy of using non-linear pedagogy to support attacking players’ individual learning objectives in elite-youth football: A randomised cross-over trial     

Simon J. Roberts  James R. Rudd  Matthew J. Reeves 《Journal of sports sciences》2020,38(11-12):1454-1464

ABSTRACT

The present study examined the efficacy of a coaching curriculum, based on non-linear pedagogy, on improving attacking players’ individual learning objectives (ILOs) in elite-youth football. Participants included 22 attacking players (i.e., centre-forwards, wide-players and attacking midfield players) from a professional football academy in England. The players were randomly appointed to both control (CON) and intervention (INT) periods following baseline measures. The INT (non-linear) and CON (linear) periods were both designed to support the ILOs provided to each player as part of the elite player performance plan. The study adopted a randomised cross-over design and ILOs considered important for attacking players (i.e., strong foot finishing, weak foot finishing, 1-v-1 and decision-making) were evaluated using the Loughborough Shooting Skill Test. The results showed significant differences for INT in 1-v-1 (P< 0.02) and decision-making (P< 0.01). However, there were no significant differences for strong foot finishing, weak foot finishing or time taken. These results support non-linear pedagogy in developing 1-v-1 game play and decision-making but not for technical shooting proficiency.  相似文献