Braided composite materials for the production of lightweight, high rigidity golf shafts   总被引：1，自引：1，他引：0  

Douglas Steven S. Swanek  Jason Carey 《Sports Engineering》2007,10(4):195-208

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   

A lecture on “matter,” including “radiant matter”     

Alexander E. Outerbridge 《Journal of The Franklin Institute》1885,120(3):178-188

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Correction Formulas for Correlations Restricted by Selection on an Unmeasured Variable     

Ralph A. Alexander 《Journal of Educational Measurement》1990,27(2):187-189

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‘Muscles for Motherhood’: A Genealogical Analysis of Medicalized Ways of Knowing Female Footballers in New Zealand, 1921 and 1973–1975     

Barbara Douglas Cox  Richard Pringle 《国际体育史杂志》2015,32(18):2135-2149

ABSTRACT

Michel Foucault argued that females gradually became integrated into the sphere of medical practices through a process which he termed as a ‘hysterization of women’s bodies’ (Foucault, The History of Sexuality, Volume One: An Introduction, New York: Pantheon Books, 1978, 104). In this article, we draw on Foucault to examine how women’s bodies, exercise and motherhood impacted on the historical development of female football in New Zealand within two time periods (1921 and 1973–1975). Employing his genealogical framework, we analyze newspaper reports, historical documents and conducted in-depth interviews to demonstrate how medical/scientific discourses both constrained and enabled the participation of women in football. We conclude that while medical knowledge was used to publicly disqualify the legitimacy of the female footballer in 1921, and hence her abrupt disappearance from the sporting realm, the absence of such medical knowledge in the early 1970s, combined with societal changes associated with second wave feminism, paved the way for the eventual ‘normalization’ of female football in New Zealand.  相似文献   

心的中心地位:道家之间的论战     

达格拉斯·贝格美 《商丘师范学院学报》2015,(2):29-33

心与身体其他感觉器官的关系问题,备受先秦两汉所有重要思想流派的争议。众所周知,传统儒家认为心是主"情"的器官,并具有分析其他感官之间差异的能力1。对于孟子来说,"四端"学说就是关于"心"的内容,最为显著的是恻隐之心,它能促进人们德性的成长2。对于儒家来说,与其他自然的感觉器官相比,"心"是较为高级的。因为它不仅具有思考的能力,而且能评估人们所遇之事;而其他感知器官,仅仅是在于接触其他事物3。"心"比其  相似文献   

Talent,Schmalent: An Instructional Design/Action Research Framework for the Professionalization of Teaching in Academic Libraries     

Alexander J. Carroll  Kevin Michael Klipfel 《The Journal of Academic Librarianship》2019,45(2):110-118

When myths become canonical beliefs within a professional culture, they can have a profound impact on professional practice. In this paper we identify as a pernicious educational myth the belief that the ability to teach well is a naturally occurring innate talent or skill. The first two sections of the paper aim to demonstrate (i) that the concept of the naturally gifted teacher is a myth based on factually incorrect assumptions about expertise development and (ii) that this myth has several major negative implications for professional practices around teaching in academic libraries. We then we draw on the education literature to offer an alternative model for the cultivation of teaching excellence, an instructional design/action research framework that prioritizes ‘deliberative’ practice over innate talent. We close with suggestions for how academic librarians and library administrators can implement this framework within their institutions.  相似文献   

Cognitive load in algebra: element interactivity in solving equations     

Bing Hiong Ngu  Siu Fung Chung  Alexander Seeshing Yeung 《教育心理学》2015,35(3):271-293

Central to equation solving is the maintenance of equivalence on both sides of the equation. However, when the process involves an interaction of multiple elements, solving an equation can impose a high cognitive load. The balance method requires operations on both sides of the equation, whereas the inverse method involves operations on one side only. In an experiment, middle school students (N?=?71) were randomly assigned to the balance and inverse methods to complete a pre-test, an acquisition phase and a post-test. Pre-test and post-test comparisons found that the inverse group outperformed the balance group for those equations that involved high element interactivity. Instructional efficiency measures further confirmed that the balance method imposed higher cognitive load. The inverse method was capable of reducing cognitive load due to the interacting elements.  相似文献   

Validity of Social,Moral and Emotional Facets of Self-Description Questionnaire II     

Kim Chau Leung  Herbert W. Marsh  Alexander Seeshing Yeung  Adel S. Abduljabbar 《Journal of Experimental Education》2015,83(1):1-23

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Familial and Institutional Factors: Job Satisfaction for Female Counselor Educators     

Carrie Alexander‐Albritton  Nicole R. Hill 《Counselor Education & Supervision》2015,54(2):109-121

Job satisfaction based on familial and institutional factors was explored for 157 female counselor educators. Results indicate that female associate professors had lower levels of intrinsic rewards domain after controlling for institutional type. Parental responsibility and partnership status were equivocal, with significant interaction effects after controlling for Carnegie Classification.  相似文献   

Phonological Processing and Word Reading in Typically Developing and Reading Disabled Children: Severity Matters     

Barry J. A. de Groot  Kees P. van den Bos  Alexander E. M. G. Minnaert  Bieuwe F. van der Meulen 《Scientific Studies of Reading》2015,19(2):166-181

In this study word reading (WR) fluency was used to dichotomously classify 1,598 Dutch children at different cutoffs, indicating (very) poor or (very) good reading performance. Analysis of variance and receiver operating characteristics were used to investigate the effects of rapid automatized naming (RAN) and phonemic awareness (PA) in predicting group membership. The highest predictive values were found for the combination of RAN and PA, particularly for the poorest readers. Furthermore, results indicate that with the severity of impairment, WR is more dominated by deficient PA, which is interpreted as an enduring problem with sublexical processing. Another main result is that with the increase of reading skill, the contribution of PA diminishes, whereas the contribution of RAN remains fairly constant for the whole reading fluency continuum. These results warrant the conclusion that whereas PA hallmarks reading disability, RAN appears to be the default predictor for above-average or excellent reading proficiency.  相似文献