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81.
A non-rotational (NR) shot is now a well-known scoring move in soccer. To execute the NR shot, it is necessary to deprive the ball of any rotational forces during the impact phase. To execute the NR shot, it is natural that the force vector acting from the foot would pass through the ball’s center of gravity; however, the coordinated motion of the lower limb joint’s angular displacement and the pelvis is still unclear. The aim of this study is to estimate the coordinated leg and pelvis motion during the NR shot as compared to that during instep kicking. Four right-leg dominant college league players were asked to perform a NR shot and an instep kick a total of 10 times each. Hip, knee, and ankle joint angular displacements in the sagittal plane and pelvis yaw and roll rotational motions during both types of kicks were calculated with 14 IR reflective markers using a 3D real-time motion analysis system with a 250-Hz sampling. The Euclidean distances of the joint space of the NR shot and the instep kick were also calculated to detect similarities in the coordinated motion of the lower limb. The results showed that the lower limb joint motions in the sagittal plane were not different; however, the pelvis roll and yaw motions were apparently different, and these phenomena could simulate a pendulum motion with changes in both the vertical and horizontal displacements. These results suggest that the coordinated motion of the lower limb joint’s angular displacement shows high similarity between the NR shot and the instep kick, and the pelvis roll and yaw synchronized orientation is essential for achieving the NR shot. 相似文献
82.
Richard James 《高等教育研究与发展》1995,14(2):185-199
The academic award restructuring of 1991 established a trial period for academic staff appraisal for the purposes of staff development. The trend in Australia towards more formal performance management for academics has occurred during a period of substantial change to the structure of higher education and institutional management, and brought debate on whether appraisal, for either summative purposes (where performance assessment is for remuneration or promotion purposes) or formative purposes (where the emphasis is on planning personal development), is appropriate for academic staff. Arguments have been put forward for the benefits of appraisal processes with primarily developmental intent. Thus far there have been reports of the characteristics and processes of appraisal schemes, but less data on outcomes; in particular, little evidence to indicate the extent to which schemes lead to worthwhile staff development. This paper reports selected findings of a study of the evolving appraisal scheme of The University of Melbourne. The study was conducted after the scheme's second year of operation by the Centre for the Study of Higher Education which played an advisory role in an internal review of the scheme. The findings reveal some uncertainty among staff about the intentions of the scheme, and tensions between summative and formative purposes, perhaps not surprising given the contentious issue which staff appraisal has been in higher education. Nevertheless, positive outcomes were identified, but possibly too few to claim that the scheme was fully achieving a developmental objective. These findings raise questions about the effectiveness of academic staff appraisal nationally and suggest that it is time to reconsider the policy linkage between appraisal and staff development. 相似文献
83.
With advanced prediction modes of intra prediction, intra coding of H.264/AVC offers significant coding gains compared with previous video coding standards. It uses an important tool called Lagrangian rate-distortion optimization (RDO) technique to decide the best coding mode for a block, but the computational burden is extremely high. In this paper, we proposed an improved fast intra prediction algorithm including block type selection and mode decision algorithm based on analysis of edge feature of a block. Our algorithm filters out unlikely block type and candidate modes to reduce the RDO calculations. Experimental results showed that the proposed algorithm can reduce the computation complexity of intra prediction from 52.90% to 56.31%, with 0.04 dB PSNR degradation and 2% increase of bit rate. 相似文献
84.
Richard E. Wakeford 《Assessment & Evaluation in Higher Education》1981,6(3):206-217
The importance of the ethos or learning environment of a training institution is increasingly being appreciated in terms of its effect on learning process and outcome. This paper reports upon the development of an inventory to measure medical students’ perceptions of their learning environment and upon its pilot use to contrast their experiences in five British medical schools. Broad similarities were found between the medical schools upon some dimensions of the questionnaire, but a number of substantial differences are also reported. It is concluded that it is by no means difficult to develop an instrument which can identify important differences between institutions’ learning milieux. However, reservations are expressed about making other than tentative conclusions from the details of the findings of similarities and differences: the desirability of conducting a more comprehensive study is emphasised. 相似文献
85.
A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated
by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction
among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the
interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice
mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed.
The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and
the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers,
which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected
in clinical task-based interviews. 相似文献
86.
87.
1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec… 相似文献
88.
89.
Children with hyperlexia who learn to readspontaneously before the age of five are impaired inreading and listening comprehension but have wordrecognition skills well above their measured cognitiveand linguistic abilities. In a previous study, theauthor administered a battery of cognitive, academicachievement, and phonemic awareness tests to threechildren classified as hyperlexic. The findingsshowed that the levels of phonemic awareness of thesechildren were low and not commensurate with their wordreading skill. In the present study, the authorreevaluated the three children approximately 7–8 yearslater with the same battery of cognitive, academicachievement, and phonemic awareness tests as well asseveral additional measures of phonemic awareness. The results showed that all three childrens' levels ofphonemic awareness were still low and not commensuratewith their word reading skill. Other findings showedthat two of the children, both of whom had remained inspecial education classes since the previous study,continued to be voracious readers. The other child,who had always been in regular education classes, hadnot read very much for several years. Findings alsoshowed that the word recognition skills of two of thechildren, including the child who had always attendedregular education, had decreased by one to twostandard deviations. 相似文献
90.