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 Based on the experiments done in wind tunnel on javelin,the author established a mathematical model of javelin flying with computer optimization and obtained the results with laws. The proper conditions of javelin release were also analysed. With the initial velocity of throwing within 2530m/s,the optimum conditions of releasing javelin are: the optimum angle of projection is 40°,the angle of attack is11°. As far the effect of throwing javelin,better performance will be achieved with a minus angle of attack... Based on the experiments done in wind tunnel on javelin,the author established a mathematical model of javelin flying with computer optimization and obtained the results with laws. The proper conditions of javelin release were also analysed. With the initial velocity of throwing within 2530m/s,the optimum conditions of releasing javelin are: the optimum angle of projection is 40°,the angle of attack is11°. As far the effect of throwing javelin,better performance will be achieved with a minus angle of attack than with zero angle of attack, while the latter will result in longer distance than a plus angle of attack. In case of poor conditions, the performance with low center of gravity javelin will be worse than that with the old model javelin. In general,the angle of throwing should not be small,and the absolute value of angle of attack should not be large, so that longer distance of throwing coule be obtained. Releasing force should not be applied along with the axis of javelin. The angle of attk should not be equal to zero,in order to obtain aerodynamic effects.  在标枪风洞测力实验基础上,建立标枪飞行数理模型进行计算机优化,得到了有规律的结论,结合投掷实践分析了标枪出手适宜条件。出手初速在25m/s～30m/s的范围内,最佳出手条件是:投掷角为40°,迎角为11°。就投掷成绩而言,负攻角比零攻角好,零攻角又比正攻角好。低重心标枪俯仰力矩值比旧标枪大,低重心标枪出手条件不好,投掷成绩下降幅度比旧标枪大。一般情况下投掷角不能小,攻角绝对值不能大,这样相应成绩更好些。投掷标枪不能沿纵轴用力,也不可能沿纵轴用力。标枪以不为零的攻角出手是获得空气动力效率的充分必要条件。  The main factors which affect shot put,are:the initial velocity,angle of throwing and the height of throwing.However,these three factors depend on more elements.With the help of substantial related references,the author would like to dwell on such aspects from the angle of sports biomechanics as the initial velocity,the working distance and time of final push and the height of ascending shot under the final push.  通过查阅大量相关资料 ,从出手角度、最后用力的工作距离和时间、铅球最后用力上升的高度等方面 ,运用运动生物力学的原理进行分析研究。  Through motional point the article analyses the features of shot in the final throwing process. It thinks that the movement of the shot begins with the final forcefully throwing process. On the basis of this a new formula on the optimum angle of throwing the shot is produced. Also through practical materials the writer finds that the new formula and practice highly match with each other. It is objective right that the new formula is regarded as the theory basis of the optimum angle of the throwing... Through motional point the article analyses the features of shot in the final throwing process. It thinks that the movement of the shot begins with the final forcefully throwing process. On the basis of this a new formula on the optimum angle of throwing the shot is produced. Also through practical materials the writer finds that the new formula and practice highly match with each other. It is objective right that the new formula is regarded as the theory basis of the optimum angle of the throwing shot.  从运动角度分析了铅球在最后用力过程中的运动特征,认为铅球的抛射运动是从出手前最后用力阶段开始的.以次为依据,通过数理运算,推导出了铅球最佳出手角度理论计算“新”公式.实践验证指出,新公式与实践基本达到了吻合.表明新公式作为铅球最佳出手角度的理论依据是客观准确地.  
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