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991.
If instructional designers hold limited views about their practice they sometimes adopt formulaic routines that do not help them accomplish the goals they believe are important, or develop instruction of a quality envisioned by the field??s innovative theorists. Fortunately, designers can avoid these unfavorable results in part by understanding and exemplifying the creative spirit of design. In this article the author examines the creative spirit of design, exploring its imaginative, creation-oriented, and inter-disciplinary character. The author also describes how the creative spirit can help instructional designers remain flexible and perceptive in their practice, and by so doing be better able to create effective and innovative instruction of a quality consistent with their ultimate ideals.  相似文献   
992.
The purpose of this study was to evaluate the effects of whole-body vibration (WBV) on the muscle recruitment of selected upper and lower body muscles during the baseball swing. Participants were recreationally trained males (n = 16, 22 +/- 2 years, 181.4 +/- 7.4 cm, 84.7 +/- 9.0 kg), with previous baseball experience. Subjects participated in three randomized sessions on separate days, consisting of three sets of five swings offa hitting tee. Exercises (upper and lower body dynamic and static movements) with or without WBVexposure were performed between swing sets. During each swing, the gastrocnemius, biceps femoris, gluteus maximus, pectoralis major, latissimus dorsi, and triceps brachii were evaluated for electromyographic (EMG) activity. EMG values were normalized to EMG measured during maximal voluntary isometric contraction. Statistical analysis revealed no significant differences in EMG activity across the three treatments. In addition, the results displayed a specific muscle recruitment order during the swing, starting with the lower body followed by the upper body muscles. This study was the first to report the recruitment order during the baseball swing. Although acute exposure to WBV did not significantly alter the muscle recruitment, these results may prove useful for practitioners looking to enhance baseball swing performance.  相似文献   
993.
Embedded programming and real-time signal processing of swimming strokes   总被引:2,自引:1,他引:1  
The research outlined in this paper was conducted to allow real-time processing, transmission and presentation of data to swimming coaches and subsequently their swimmers in a training environment, focused on providing information relevant to strokes in free swimming. This was achieved using a wearable wireless sensor and embedded programming techniques, using accelerations involved in the swimming stroke to provide relevant features for coaches. Current methods used do not offer real-time response to coaches, which results in the lack of real-time feedback and significantly increased post-session analysis time. Filtering and signal processing algorithms are described here, which allow real-time data analysis to be embedded within a wireless sensor node. The system significantly reduces the time for processing acquired data and has delivered a novel monitoring device suitable for operation within the harsh environment of the pool.  相似文献   
994.
A number of recent studies have measured the extent and timing of segment rotation during the golf swing. A promising technique, instantaneous screw axis (ISA) theory, could provide a better expression of segment rotation. In Part 1 of this two-part study, the objectives are to identify the ISA of the pelvis, shoulders and left arm during the downswing, compute segment angular velocity relative to that segment’s ISA and verify that ISA theory is a valid tool to analyse segment rotation during the golf swing. Results indicate that for all subjects, at least 71% of marker velocity is a result of rotation about their respective ISA, when averaging results over the duration of the downswing, confirming that motion is primarily rotational. Furthermore, ISA position and orientation of each segment approaches, on average, the expected gross axis of rotation, confirming that motion about the ISA is representative of joint motion.  相似文献   
995.
A deterministic model is a modeling paradigm that determines the relationships between a movement outcome measure and the biomechanical factors that produce such a measure. This review provides an overview of the use of deterministic models in biomechanics research, a historical summary of this research, and an analysis of the advantages and disadvantages of using deterministic models. The deterministic model approach has been utilized in technique analysis over the last three decades, especially in swimming, athletics field events, and gymnastics. In addition to their applications in sports and exercise biomechanics, deterministic models have been applied successfully in research on selected motor skills. The advantage of the deterministic model approach is that it helps to avoid selecting performance or injury variables arbitrarily and to provide the necessary theoretical basis for examining the relative importance of various factors that influence the outcome of a movement task. Several disadvantages of deterministic models, such as the use of subjective measures for the performance outcome, were discussed. It is recommended that exercise and sports biomechanics scholars should consider using deterministic models to help identify meaningful dependent variables in their studies.  相似文献   
996.
对足球运动员在长期训练过程中身体准备的综合体系进行了分析。长期的研究结果表明,足球运动训练可以被划分为4个方面:1)单纯性身体活动的使用,2)不同目标训练过程的交替使用,3)较小训练周期固定结构的保留并作为训练过程的基础,4)专门性推动能力的有序发展。这4个方面可以有效地解决足球运动员全面身体准备的问题。  相似文献   
997.
为使合格球队的训练和比赛过程更具有现代化,研究人员提出了增加远距离投篮有效性的结构内容模式,并将投篮训练作为运动员技、战术的组成部分。投篮训练是一项专门性训练,要在不同情况下完成不同方式的投篮练习。通过各种不同的训练方式来掌握投篮技术并提高投篮的准确性。该模式是用来为每一名选手选取远距离和超长距离投篮方式,完善投篮技术,选择技、战术行为,制定不同训练周期和阶段个人和全队的投篮训练。结论:提高篮球远距离投篮效果的模式可以达到如下目的:1)队员的有效安排;2)完善投篮技术;3)为每一名选手选择不同的投篮训练模式;4)每一名队员投篮准确性的数据资料可以为全队的战术安排提供参考;5)定性地规划每一名球员和球队的投篮训练并作为球队技、战术训练的主要组成部分。  相似文献   
998.
This paper presents a novel sensor technology to deduce the dynamics of a bowling ball. The sensor, a miniature wireless inertial measurement unit (IMU), incorporates MEMS accelerometers and angular rate gyros, a microcontroller, a low power RF transceiver, and a rechargeable battery. When embedded in a bowling ball, the IMU transmits the acceleration and angular velocity data that define the dynamics of the ball starting with the bowler’s delivery and its motion in the lane. Example results from professional bowlers illustrate how this technology can be used to assess bowler skill and ball performance. For instance, the IMU accurately measures the spin dynamics of the ball which are crucial to develop the ball “hook.” An analysis of ball dynamics in the lane is distilled to a measurable “hook potential” metric for further assessing bowler skill. Finally, the sensor presented herein is believed to be the world’s smallest, wireless IMU. This highly miniaturized and wireless design will enable parallel training systems for many sports, including basketball, baseball, crew, cricket, golf, fly fishing, soccer, softball, tennis, rowing, among others.  相似文献   
999.
A new approach to decision support in a multiobjective problem arising in controlled dynamic system design is described. The approach basically extends the feasible goals method that implies specifying the goal point by visualizing the Pareto frontier that characterizes feasible objective values and objective tradeoffs to dynamic systems. The developed approach helps explore dynamic modifications of the Pareto frontier.  相似文献   
1000.
This paper reflects the results of the analysis of user information needs that was carried out by the Library of Natural Sciences of the Russian Academy of Sciences (LNS RAS) for the purpose of gathering information on the quality of a reference-bibliographic and information service for specialists of the RAS in the subject of their studies.  相似文献   
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