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Gifted/talented education is slowly expanding as more funds for programs are provided by states and more universities off er graduate programs.  相似文献   
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The paper provides (1) a teacher-administered rating instrument for inattention without confounding the rating with hyperactivity and conduct disorder, and (2) evidence that the ratings correlate with the scores obtained from cognitive tests of attention. In Study I, the first objective was to investigate the construct validity and the inter-rater reliability of the Attention Checklist (ACL) by factor analysing the teacher ratings of 110 Grade 4 children, obtained by using the ACL. The second objective was to investigate the predictive validity of the ACL by examining the relationship between the scores obtained for the participants from teachers' ratings using the ACL and the scores obtained by participants in the lab-type attention tests. The results of factor analysis showed that a single factor labelled ‘inattention’ underlies the 12 items in the ACL. Examining the differences in performance on attention tests, the ‘low attention’ children as rated by the teachers on the ACL scored lower than the ‘high attention’ children on the objective tests of attention. These findings were replicated in Study II, which was conducted to test further the construct validity and predictive validity of the ACL. This time, only those two tests (Auditory Attention and Visual Attention) that had shown relatively poor discrimination between the high and low attention groups in Study I were, again, administered to another cohort of 97 Grade 4 children, as it was our intention to further challenge the reliability of the ACL. Overall, the results of both studies suggest that comprehensive assessment of attention skills should include both ACL and objective measures of selective attention.  相似文献   
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The influence of moment of inertia on baseball/softball bat swing speed   总被引:1,自引:1,他引:0  
The speed at which a player can swing a bat is central to the games of baseball and softball, determining, to a large extent, the hit speed of the ball. Experimental and analytical studies of bat swing speed were conducted with particular emphasis on the influence of bat moment of inertia on swing speed. Two distinct sets of experiments measured the swing speed of colege baseball and fast-pitch softball players using weighted rods and modified bats. The swing targets included flexible targets, balls on a tee and machine pitched balls. Internal mass alterations provided a range of inertial properties. The average measured speeds, from 22 to 31 m s−1, are consistent with previous studies. Bat speed approximately correlates with the moment of inertia of the bat about a vertical axis of rotation through the batter's body, the speed generally decreasing as this moment of inertia increases. The analytical model assumes pure rotation of the batter/bat system about a vertical axis through the batter's body. Aerodynamic drag of the batter's arms and the bat is included in the model. The independent variable is bat moment of inertia about the rotation axis. There is reasonable agreement between the model and the measured speeds. Detailed differences between the two suggest the importance of additional degrees of freedom in determining swing speed.  相似文献   
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