Contribution of uncertainty in estimation of active drag using assisted towing method in front crawl swimming     

Pendar Hazrati  Peter James Sinclair  Wayne Spratford  René Edouard Ferdinands  Bruce Robert Mason 《Journal of sports sciences》2018,36(1):7-13

Active drag force in swimming can be calculated from a function of five different variables: swim velocity, tow velocity, belt force, power output and exponent of velocity. The accuracy of the drag force value is dependent on the accuracy of each variable, and on the contribution of each variable to drag estimation. To calculate uncertainty in drag value, first the derivatives of the active drag equation with respect to each variable were obtained. Second, these were multiplied by the uncertainty of that variable. Twelve national age and open level swimmers were recruited to complete four free swimming and five active drag trials. The uncertainties for the free and the tow swim velocities, and for the belt force, contributed approximately 5–6% and 2–3% error, respectively, in calculation of drag. The result of the uncertainty of the velocity exponent (1.8–2.6) indicated a contribution of about 6% error in active drag. The contribution of unequal power output showed that if a power changed 7.5% between conditions, it would lead to about 30% error in calculated drag. Consequently, if a swimmer did not maintain constant power output between conditions, there would be substantial errors in the calculation of active drag.  相似文献   

A comparison of subjective and objective measures of physical exertion     

Monica Skatrud-Mickelson  Joan Benson  James C. Hannon  E. Wayne Askew 《Journal of sports sciences》2013,31(15):1635-1644

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Towards numeracy for the third millennium: A study of the future of mathematics and mathematics education     

Peter L. Galbraith  Marjorie C. Carss  Richard D. Grice  Lovie Endean  Merle C. Warry 《Educational Studies in Mathematics》1992,23(6):569-593

The research reported here has sought to identify target skills and abilities that will compose a future numeracy, so that new expertise can be incorporated and the exposed deficiencies remedied within a dynamic rather than static concept of competency. A nation-wide selection of panellists contributed to a three-round Delphi process, with the final data comprising both structured responses and qualitative comment. The scope of the items covered calculating activities, writing activities, reading activities, physical skills, supporting (mental) skills, applications, and problem solving. Responses to the structured items have provided priorities for numeracy for the turn of the century, in terms of both expected and desired characteristics. In general, expectations for numeracy fall short of the levels deemed desirable by panel consensus. The qualitative comments have been incorporated into three scenarios reflecting altermative visions for the future. A comparison of the scenarios uncovers wide differences between informed thinkers with respect to future visions of the ends, means, and mechanics of learning. These differences among individuals who are otherwise consistent in their views of future needs must be addressed if the identified priorities are not to be lost in a quagmire of conflicting interests, opinions, priorities, and values.  相似文献   

An approach through the looking-glass     

Wayne A. Hershberger 《Learning & behavior》1986,14(4):443-451

Forty food-deprived cockerel chicks were tested individually in a straight runway containing a familiar food cup that moved when the chicks moved. The food cup always moved in the same direction as the chick: For 20 experimental chicks it moved twice as far as the chick; for 20 control chicks it moved half as far. In Lewis Carroll’s (1898/1926) picturesque terminology, the experimental chicks were tested in Alice’s “room through the looking-glass,” in which, in order to approach the food cup, they had to “walk the other way.” Although the control chicks performed well, the experimental chicks evinced the runway behavior that characterizes positive feedback: They persistently chased the food cup away. This means that the spatial polarity of visual feedback is critical and implies that an ordinary approach response is but an automatic (closed-loop) realization of an intended visual perception.  相似文献   

The policyscape of transgender equality and gender diversity in the Western Australian education system: a case study     

Wendy Cumming-Potvin  Wayne Martino 《Gender and education》2018,30(6):715-735

ABSTRACT

In this paper, our purpose is to investigate policy informing texts and discourses referencing transgender equality and gender diversity in the Western Australian education system. Drawing on scholarship from transgender, queer and policy studies, we highlight the interplay of progressive and conservative forces affecting the Western Australian education system’s commitment to supporting transgender and gender non-binary students. Based on a Social Sciences and Humanities Research Council of Canada (SSHRC) project, the paper constructs a Western Australian case study, which threads together the critical examination of policy informing texts, qualitative interview data and media discourses surrounding public narratives, such as the Safe School Coalition Australia’s attempt to implement a school program, which builds awareness about gender and sexual diversity. Emerging through the material, discursive and spatial elements of locales and networks, our case study has the potential to deepen knowledge regarding the heuristic capacity of employing policyscape as an analytic category. In this vein, we draw attention to the possibilities and challenges for re-conceptualizing gender and providing trans-affirmative school spaces that promote equality.  相似文献   

Evaluation of the PSNS course. II: Results     

Wayne W. Welch 《科学教学研究杂志》1972,9(2):147-156

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Getting boys’ education ‘right’: the Australian Government’s Parliamentary Inquiry Report as an exemplary instance of recuperative masculinity politics   总被引：2，自引：2，他引：2  

Martin Mills  Wayne Martino 《British Journal of Sociology of Education》2007,28(1):5-21

This paper focuses on the Australian federal Parliamentary Inquiry into Boys’ Education, Boys: Getting it Right, which is shown to be an exemplary instance of recuperative masculinity politics. The paper demonstrates how, through a variety of rhetorical strategies, its anti‐feminist politics are masked and how the report works with essentialised differences between boys and girls. The argument is demonstrated through a focus on a number of the report’s recommendations, including the call for a recasting of current gender policy, the need for creating so‐called ‘boy‐friendly’ curricula, assessment and pedagogical practices, and for employment of more male teachers. The report draws on populist literature and submissions from the boys’ lobby, as well as practice‐oriented submissions to the neglect of theoretically oriented and (pro‐)feminist work. As such, the significance of the construction of masculinities to boys’ attachment to and performances in school is totally neglected, limiting the value of the report’s recommendations for improving schooling for both boys and girls.  相似文献   

Hurdle-jump responding in the rat as a function of conspecific odor of reward and nonreward     

Ira Collerain  H. Wayne Ludvigson 《Learning & behavior》1977,5(2):177-183

A hurdle-jump escape response was employed to assess the laboratory rat’s aversion or attraction to different types of conspecific odor. Odorant donor subjects received 112 runway acquisition trials on a continuous reward schedule followed by 32 extinction trials, 112 acquisition trials on a 50% schedule of reward and nonreward followed by 32 extinction trials, or 144 “neutral” trials with no reward in the alley. Different groups of test subjects escaped from odor excreted by odorant subjects on (a) nonrewarded acquisition and extinction trials, (b) rewarded trials during continuous reinforcement, (c) rewarded trials during partial reinforcement, or (d) neutral trials; others escaped from a clean box. The principal findings were: (1) significant aversion to “odor of nonreward” appeared after the donor odorants had received 12 exposures to reward; (2) production of odor of nonreward by odorant subjects changed as a function of training experience with reward; (3) after repeated exposure to odor of nonreward, the escape response habituated; (4) greater or different odor excretion in extinction resulted from subjects trained on a continuous reward schedule than on a partial reward schedule. Relationships of the data to frustration theory were discussed, assuming that inferred differences in production of odor reflect differences in frustration reaction.  相似文献   

'The Kids are Doing All Right': Differences in parental satisfaction,expectation and attribution in St Petersburg,Sunderland and     

Julian G Elliott  Neil Hufton  Leonid Illushin  Wayne Willis 《Cambridge Journal of Education》2001,31(2):179-204

Comparative studies of attitudes in different countries have resulted in the claim that parents in the USA and England tend to have unrealistically positive views of their children's schools and academic performance. Low expectations, together with a belief in the importance of natural ability, it has been argued, lead to low standards and reduce striving to succeed. The present study builds upon earlier investigations of children's attitudes, beliefs and behaviours in Sunderland, Eastern Kentucky and St Petersburg by surveying parental perspectives. Findings from these three regions reinforce earlier findings about English and American complacency and the more demanding nature of the Russian context. In line with our earlier studies, and contrary to the suggestion of a number of writers, an emphasis upon effort, rather than ability, was a strong feature of the English and American responses, although it is pointed out that such beliefs may not actually result in high work rates. The paper concludes by suggesting that the important role of parents in instilling important attitudes and behaviours in their children is undermined by the current emphasis upon schools as fundamentally responsible for ensuring high levels of achievement.  相似文献   

Molecular thermodynamics for cell biology as taught with boxes     

Mayorga LS  López MJ  Becker WM 《CBE life sciences education》2012,11(1):31-38

Thermodynamic principles are basic to an understanding of the complex fluxes of energy and information required to keep cells alive. These microscopic machines are nonequilibrium systems at the micron scale that are maintained in pseudo-steady-state conditions by very sophisticated processes. Therefore, several nonstandard concepts need to be taught to rationalize why these very ordered systems proliferate actively all over our planet in seeming contradiction to the second law of thermodynamics. We propose a model consisting of boxes with different shapes that contain small balls that are in constant motion due to a stream of air blowing from below. This is a simple macroscopic system that can be easily visualized by students and that can be understood as mimicking the behavior of a set of molecules exchanging energy. With such boxes, the basic concepts of entropy, enthalpy, and free energy can be taught while reinforcing a molecular understanding of the concepts and stressing the stochastic nature of the thermodynamic laws. In addition, time-related concepts, such as reaction rates and activation energy, can be readily visualized. Moreover, the boxes provide an intuitive way to introduce the role in cellular organization of "information" and Maxwell's demons operating under nonequilibrium conditions.  相似文献