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Braided composite materials for the production of lightweight, high rigidity golf shafts 总被引:1,自引:1,他引:0
Braiding is not currently used in the production of golf shafts. The objective of this work was to develop, through a modelling
process consisting of altering lamina sequence, a golf shaft, using braided laminas, which would have mass, stiffness and
torque comparable to commercially available composite and steel shafts. A 2D conical braided composite model was previously
developed and validated to predict elastic constants of braided closed meshed structures. Energy methods were used to calculate
the stiffness and torque of shafts using prescribed industry approaches. Shaft mass was calculated based on geometry and density
of constitutent materials. Modelled shafts had both braided and unidirectional layers and compared favourably with or were
better than commercially available composite and steel shafts in terms of deflection force and twist angle; they had the same
weight as composite shafts but were much lighter than steel shafts. If these findings are verified, braided composites would
be a viable and effective approach to the design of future golf shafts. 相似文献
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Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do explanations made by experts from different biology subdisciplines at a university support the validity of this model? Guided by the modeling framework of R. S. Justi and J. K. Gilbert, the validity of an initial model was tested by asking seven biologists to explain a molecular mechanism of their choice. Data were collected from interviews, artifacts, and drawings, and then subjected to thematic analysis. We found that biologists explained the specific activities and organization of entities of the mechanism. In addition, they contextualized explanations according to their biological and social significance; integrated explanations with methods, instruments, and measurements; and used analogies and narrated stories. The derived methods, analogies, context, and how themes informed the development of our final MACH model of mechanistic explanations. Future research will test the potential of the MACH model as a guiding framework for instruction to enhance the quality of student explanations. 相似文献
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Jack Anderson 《国际体育史杂志》2015,32(15):1764-1768
The brief note aims to illustrate how historical context has contributed to my writing on modern sports law and principally through two pieces of work – the first relating to the historical, sui generis origins of the legality of combat or fighting sports, which continues to stretch the boundaries of core principles of criminal law, such as reasonable consent to bodily harm, to their utmost; and second, and more generally, the ‘historicalegal’ influences on the development of modern sport in mid-nineteenth-century Britain. Before that is done, it is best to give some account of research methodologies in legal scholarship and principally as they apply to legal history. 相似文献