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41.
ABSTRACT

The aim of this study was to assess if tactical and technical performance indicators (PIs) could be used in combination to model match outcomes in Australian Football (AF). A database of 101 technical PIs and 14 tactical PIs from every match in the 2009–2016 Australian Football League (AFL) seasons was merged. Two outcome measures Win-loss and Score margin were used as dependent variables. The top 45 ranked technical and tactical PIs from a feature selection process were used to model match outcome using decision tree and Generalised Linear Models (GLMs). Of the top 45 selected features, this included seven tactical PIs. The Win-loss-based Decision tree model achieved a classification accuracy of 89.0% and GLM 93.2%. A Score margin-based GLM achieved a root mean squared error (RMSE) of 6.9 points. A combined approach to the classification of match outcomes provided no improvement in model accuracy compared with previous literature. However, this study has established the relative importance of technical and tactical measures of performance in relation to successful team performance in AF.  相似文献   
42.
The purpose of this study was to investigate the relationship between the cable force and linear hammer speed in the hammer throw and to identify how the magnitude and direction of the cable force affects the fluctuations in linear hammer speed. Five male (height: 1.88 +/- 0.06 m; body mass: 106.23 +/- 4.83 kg) and five female (height: 1.69 +/- 0.05 m; body mass: 101.60 +/- 20.92 kg) throwers participated and were required to perform 10 throws each. The hammer's linear velocity and the cable force and its tangential component were calculated via hammer head positional data. As expected, a strong correlation was observed between decreases in the linear hammer speed and decreases in the cable force (normalised for hammer weight). A strong correlation was also found to exist between the angle by which the cable force lags the radius of rotation at its maximum (when tangential force is at its most negative) and the size of the decreases in hammer speed. These findings indicate that the most effective way to minimise the effect of the negative tangential force is to reduce the size of the lag angle.  相似文献   
43.
Background:Little is known about exercise cardiac power(ECP),defined as the ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise,on heart failure(HF)risk.We examined the association of ECP and the risk of HF.Methods:This was a population-based cohort study of 2351 men from eastern Finland.The average time to follow-up was 25 years.Participants participated at baseline in an exercise stress test.A total of 313 cases of HF occurred.Results:Men with low ECP(<9.84 mL/mmHg,the lowest quartile)had a 2.37-fold(95%confidence interval(95%CI):1.68-3.35,p<0.0001)hazards ratio of HF as compared with men with high ECP(>13.92 mL/mmHg,the highest quartile),after adjusting for age.Low ECP was associated with a 1.96-fold risk(95%CI:1.38-2.78,p<0.001)of HF after additional adjustment for conventional risk factors.After further adjustment for left ventricular hypertrophy,the results hardly changed(hazards ratio=1.87,95%CI:1.31-2.66,p<0.001).One SD increase in ECP(3.16 mL/mmHg)was associated with a decreased risk of HF by 28%(95%CI:17%-37%).Conclusion:ECP provides a noninvasive and easily available measure from cardiopulmonary exercise tests in predicting HF.However,ECP did not provide additional value over maximal oxygen uptake.  相似文献   
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School governing bodies in England have considerable powers and duties, and their formal role positions them as decision-makers. This article draws on qualitative research in the governing bodies of four maintained schools. Using deliberative democracy as a sensitising concept, the article considers some processes by which decisions are made (or not made) in governing bodies. Without claiming that governors never make decisions, it explores constraints and limitations on their ability to do so. Governors exhibit a paradoxical combination of busy-ness and passivity. On the one hand, governing bodies are constituted and structured around activity and technically decisions were made. On the other, decisions could rarely be attributed to active choices by governors. Rather, their more passive agreement with actions and positions was presented as almost unavoidable ‘common sense’, either due to the national policy context or the headteacher’s presentation of the available options.  相似文献   
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Attention is an important, multifaceted cognitive domain that includes many key cognitive processes involved in learning. This study aimed to identify the predictive links between different components of attentional skills and core calculation skills development, using two standardized measures assessing calculation (AC-MT 6–11) and attention skills (CAS) in a sample of 143 typically developing children of age range from 7.6 years to 9.4 years. The results showed that in 2nd grade, selective visuo-spatial attention emerged as an important predictor in the written calculation task, while the ability to inhibit distracting information seemed to better predict accuracy in oral calculation. In 3rd grade, visuo-spatial components of attention emerged as no longer predictive, whereas planning and active visuo-spatial attention abilities emerged as predictive of accuracy in the oral calculation task. These results confirm previous findings about the contribution that attentional skills may have in calculation skills development, supporting evidence for progressive automation attentional components over time.

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49.
The Multidimensional School Anger Inventory–Revised (MSAI-R) is a measurement tool to evaluate high school students' anger. Its psychometric features have been tested in the USA, Australia, Japan, Guatemala, and Italy. This study investigates the factor structure and psychometric quality of the Persian version of the MSAI-R using data from an administration of the inventory to 585 Iranian high school students. The study adopted the four-factor underlying structure of high school student anger derived through factor analysis in previous validation studies, which consists of: School Hostility, Anger Experience, Positive Coping, and Destructive Expressions. Confirmatory factor analysis of this four-factor model indicated that it fit the data better than a one-factor baseline model, although the fit was not perfect. The Rasch model showed a very high internal consistency among items, with no item misfitting; however, our results suggest that to represent the construct sufficiently some items should be added to Positive Coping and Destructive Expression. This finding is in agreement with Boman, Curtis, Furlong, and Smith's Rasch analysis of the MSAI-R with an Australian sample. Overall, the results from this study support the psychometric features of the Persian MSAI-R. However, results from some test items also point to the dangers inherent in adapting the same test stimuli to widely divergent cultures.  相似文献   
50.
The importance of the kinesthetic-cognitive conflict (bodily experience that contradicts cognition) in the development of thinking is rooted in Piaget's theory. This article presents three studies which demonstrate the efficiency of the kinesthetic conflict in promoting the understanding of three scientific concepts among children aged 5–12. The first study examines the effect of the kinesthetic conflict on promoting the concept of length in children aged 4.5–5.5 years; the second study compares the effect of four types of cognitive conflicts—two physical ones (visual and kinesthetic) and two social ones (between peers and between children and adults)—on promoting the concept of balance among children aged 5–6 years; and the third study compares the effect of the kinesthetic conflict with the visual conflict on promoting the concept of speed among sixth graders. In all three studies, the kinesthetic conflict was found to be the most efficient in causing a significant cognitive change. The results support Piaget's theory which determines that scientific thinking begins with the sensomotoric experience of the physical surroundings. © 1997 John Wiley & Sons, Inc. J Res Sci Teach 34: 1083–1099, 1997.  相似文献   
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