Golf shafts are normally characterised using static or quasi-static tests, yet the golf swing itself is dynamic. The purpose
of this research was to determine whether stiffness properties obtained from these tests can be used when modelling the dynamic
behaviour of golf shafts made from carbon fibre reinforced polymer (CFRP). Three shafts, matched for all properties except
shaft flex, were subjected to human swing testing by 12 skillful players whilst strains were recorded. Peak principal strains
as well as strain rates increased as shaft flex decreased (p < 0.001). CFRP flat panels with lay-ups similar to those contained in the shafts were constructed and tested statically and
at strain rates between 10−4 and 4 s−1. Some level of strain-rate dependency was found for these panels, but only for strain rates exceeding those seen during a
swing, which suggests that static material tests are appropriate for measuring the dynamic stiffness of golf shafts. 相似文献
Are Historically Black Colleges and Universities (HBCUs) necessary in the twenty-first century so-called ??post-racial?? US American context? This question is raised loudly and frequently given the contemporary social climate and economic considerations. In this article, the author offers a response to and critique of this question and surveys histories, missions, and academic and social environments of the HBCUs. He contends that HBCUs offer alternate higher education experiences for Black educators and students who find themselves on the margins of the US American academic center. Demonstrating the parallels of HBCU settings to villages, the author illustrates how these HBCU village contexts contribute to pedagogy. Ultimately, he appeals to HBCU stakeholders to intentionally and consistently promote ??village?? environments to cultivate the academic and social sensibilities of its constituents. 相似文献
Students sometimes misunderstand or misinterpret scientific content because of persistent misconceptions that need to be overcome by science education—a learning process typically called conceptual change. The acquisition of scientific content matter thus requires a transformation of the initial knowledge-state of a common-sense picture of the world to an outcome state of a scientific conception articulated with scientific concepts, which the learner did not possess prior to learning. This paper introduces a taxonomy based on the idea that multiple operational criteria are needed to evaluate conceptual change into scientific concepts. Three sets of criteria—qualitative, quantitative and experimental—are identified, and their interrelations in the process of conceptual change are explored. 相似文献
Abstract Previous studies have shown that the start plays a critical role in sliding events and explains more than 55% of the variance of the final time in luge. Experts evaluate the contribution of the arm strokes to be 23% of the total starting performance. The aim of the present study was to develop a measurement and feedback training tool (Speedpaddler) for the arm strokes of high-performance luge athletes. The construction is an aluminium alloy framework with a customary belt conveyor system, which is driven by two synchronized servo motors. Training is possible with constant speeds up to 12 m · s?1 or several speed curves, which simulate the acceleration of different luge tracks. The construction facilitates variations in the inclination and speed of the conveyor belts and thereby the resistance and movement speed. If the athlete accelerates the conveyor belts during arm-paddling, the torque of the motors decreases. Torque measurements and high-speed video offer valuable insights into the several technique criteria. Comparisons of arm-paddle cycle durations on ice and on the Speedpaddler with 18 luge athletes (national team and juniors) showed no statistical differences. The Speedpaddler might be a useful tool to improve starting performance all year round. 相似文献
International university co‐operation which serves to Internationalize science and knowledge requires that students, teachers, and scientists be internationally mobile. For mobility to occur on a wide scale, it must be the object of inter‐university and international bilateral and multilateral agreements. The various sorts of agreement which have been negotiated and enacted since the 1950's have been very successful. Recognition and equivalence must be based on qualitative rather than on quantitative factors, and above all on trust Recognition procedures could be further perfected by such actions as the preparation of a set of harmonizable recommendations, on the determination of equivalences, greater co‐operation among the various European information networks on equivalence, and publication of a manual on recognized universities in Europe. 相似文献
Sloth, O. “Experimental work at Hellerup Seminarium, Denmark,” Revue ATEE Journal 3 (1980) 37‐42.
The author describes the approach of one Danish College of Education to a problem which is by now internationally known: in this age of integration into the normal class of all but the demonstrably and severely educationally subnormal or handicapped, how can we equip student teachers, during their initial training, to cope with these problems of Special Education. He outlines the attempt at Hellerup Seminarium, Copenhagen, to solve the problem by integrating and restructuring the compulsory pedagogic subjects and educational specialisms and so build up within the legal framework what he calls a Special Education Teacher Education (SPECTE). 相似文献
This study introduces a peri‐urban context of poverty to the study of child development in Africa in contrast to the more typical assessments in middle‐class and rural contexts. Spot observations were used to assess universal caregiving behaviors toward seventy‐six 3‐month‐old infants. Results show that middle‐class infants experienced distal parenting behaviors instantiated by mothers, whereas rural children experienced proximal parenting practices in interactions with others. Infants growing up in poverty had mothers and other caretakers involved at mostly low levels. They experienced low levels of body contact, body stimulation, and object stimulation, and high levels of face‐to‐face positions. The study indicates that caregiving in the context of poverty does not necessarily follow familiar pathways and needs to be contextualized accordingly. 相似文献