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   

Oral History Interview of PCC Founding     

David Reser  Jeanne Drewes  Ann Della Porta 《Cataloging & classification quarterly》2020,58(3-4):239-247

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Between Policy and Practice: Archival Descriptions,Digital Returns and a Place for Coalescing Narratives     

Sharon Huebner  Stella Marr 《档案与原稿》2019,47(1):113-130

ABSTRACT

The Strathfieldsaye Estate collection at the University of Melbourne Archives is discussed in relation to recognising, protecting and reclaiming Koori (First Peoples of southeast Australia) heritage. The settler collection includes early 1900s photographs of Koori people within two distinct albums – a family album that includes a series of studio portraits of Koori adults and children, and an album depicting Koori families on Ramahyuck Aboriginal Mission Station. In the past, these albums have been defined by, and limited to, traditional archiving practices excluding Koori interpretation, authorship and social context. Restoring Koori ownership and authorship of intangible heritage plays a large part in consolidating ancestor photographs with Koori perspectives of identity and culture.  相似文献   

To preserve or enhance precious memories: a segmented market analysis of the history museum in Singapore     

Sharon Chang  Renuka Mahadevan 《Journal of Cultural Economics》2018,42(1):75-89

This study examines the value placed on museums by patrons and non-patrons and investigates the factors that affect this valuation with a view to boost visitorship. The total economic value of Singapore’s History Museum is at least US$57 million, and this is high relative to other countries, a fact which can be used to justify increased government funding towards museums as cultural capital. Females and high income people are the target groups for increased visitation, while among the non-patrons, the ethnic majority is another potential clientele. Somewhat surprising is the finding that neither patrons nor non-patrons see the museum as having significant tourist value, and contrary to prospect theory, there is a preference for enhancing the museum’s services over keeping the museum. These findings provide some direction for the management of the museum to improve its visitor appeal.  相似文献   

Building student-teacher relationships and improving behaviour-management for classroom teachers     

Jordan Yassine  Leigh Ann Tipton-Fisler  Barbara Katic 《Support for Learning》2020,35(3):389-407

Teachers can at times view behavioural intervention procedures as time-consuming. Thus, socially-valid classroom-based interventions are a critical component to behavioural success. This study examined the effects of traditional behavioural interventions with two kindergarten students presenting with challenging behaviours, including aggression, tantrums and noncompliance. Notably, it was found that traditional behavioural procedures were not sufficient to substantially reduce the behaviours alone. Therefore, a relationship-building component was added to target positive student-teacher relationships. Student outcomes resulted in a significant reduction in challenging behaviour as well as teacher-reported behaviours showing a reduction across all measured periods. Ongoing teacher consultation, increased student-teacher relationships (STRs) and use of effective classroom management strategies are necessary for effective models of behaviour support.  相似文献   

Administrators' ratings of competencies needed to prepare preservice teachers for oral deaf education programs     

Lartz MN  Litchfield SK 《American annals of the deaf》2005,150(5):433-442

Deaf education teacher preparation programs must prepare teachers to staff an increasing number of oral programs. A survey was conducted to determine which competencies administrators of deaf education programs rate as important for teachers in oral programs and to compare ratings of these competencies by oral school administrators to ratings made by administrators of comprehensive deaf and hard of hearing programs. Between the two groups of administrators, six areas of agreement about competencies were found. There were notable differences in the range of ratings between the two groups. These differences were attributed to the roles teachers assume in the two types of programs and the focus of instruction in each type of program.  相似文献   

Case‐based pedagogy as a context for collaborative inquiry in the Philippines     

Elvira L. Arellano  Tessie L. Barcenal  Purita P. Bilbao  Merilin A. Castellano  Sharon Nichols  Deborah J. Tippins 《科学教学研究杂志》2001,38(5):502-528

The purpose of this study was to investigate the potential for using case‐based pedagogy as a context for collaborative inquiry into the teaching and learning of elementary science. The context for this study was the elementary science teacher preparation program at West Visayas State University on the the island of Panay in Iloilo City, the Philippines. In this context, triple linguistic conventions involving the interactions of the local Ilonggo dialect, the national language of Philipino (predominantly Tagalog) and English create unique challenges for science teachers. Participants in the study included six elementary student teachers, their respective critic teachers and a research team composed of four Filipino and two U.S. science teacher educators. Two teacher‐generated case narratives serve as the centerpiece for deliberation, around which we highlight key tensions that reflect both the struggles and positive aspects of teacher learning that took place. Theoretical perspectives drawn from assumptions underlying the use of case‐based pedagogy and scholarship surrounding the community metaphor as a referent for science education curriculum inquiry influenced our understanding of tensions at the intersection of re‐presentation of science, authority of knowledge, and professional practice, at the intersection of not shared language, explicit moral codes, and indigenization, and at the intersection of identity and dilemmas in science teaching. Implications of this study are discussed with respect to the building of science teacher learning communities in both local and global contexts of reform. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 502–528, 2001  相似文献   

Recipes for fun     

Ann Cole  Carolyn Haas  Elizabeth Heller  Betty Weinberger 《Early Childhood Education Journal》1975,2(4):39-42

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Investigating Students’ Learning Through Co-designing with Technology     

Wu  Jue  Atit  Kinnari  Ramey  Kay E.  Flanagan-Hall  Grace Ann  Vondracek  Mark  Jona  Kemi  Uttal  David H. 《Journal of Science Education and Technology》2021,30(4):529-538

Involving students in the co-design of educational curricula and practices can benefit both students and teachers. Students who participate in co-design may show better learning or increased agency or engagement. In the present study, we investigated what kind of science knowledge or practices can be learned by student co-designers while engaging in co-design practices and how that learning happens with six high school students. We created a model to guide the analysis of students’ learning with technology in co-designing processes. The results revealed that students learned engineering design process even if no explicit instruction on engineering learning was given. Also, our analysis suggested that co-designing with technology enabled learning of the engineering design process and potentially furthered learning of science because it promoted knowledge integration. The results have implications for understanding and enhancing engineering design and science learning through co-designing with technology.

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Professional Cultures and Collaborative Efforts: A Case Study of Technologists and Educators Working for Change     

Ann Locke Davidson  Janet Schofield  Janet Stocks 《The Information Society》2001,17(1):21-32

The need for those working in a variety of settings to interact effectively with technical experts has grown dramatically in recent years as computers have become essential to the performance of an increasing broad range of professional work. This article presents a case of this sort of interprofessional interaction, exploring the process and outcomes of collaboration between technical professionals and educators working to bring Internet access to an urban public school district. Drawing on field note and interview data, the case reported here illustrates how differences in institutional routines and professional values can generate differing agendas, contrasting assumptions, and contrasting expectations concerning project products and outcomes among collaborators from different professional worlds. In the case we describe, these differences affected such central matters as the types and usefulness of technical resources to which users had access as well as users' confidence in the technology. The case also illustrates how aspects of this interprofessional conflict were addressed through an organizational change. The kinds of issues that arose in this project are likely to occur in a variety of professional settings; therefore, examination of this case provides insight into a variety of issues and dynamics that should be considered when embarking upon or analyzing any interprofessional collaborative effort, and particularly one that involves technical professionals.  相似文献