检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
机构地区:[1]武汉体育学院体育教育学院,湖北武汉430079 [2]香港教育学院
出 处:《沈阳体育学院学报》2013年第6期101-103,共3页Journal of Shenyang Sport University
基 金:湖北省教育厅科学研究重点项目(D20114102)
摘 要:在2012年伦敦奥运会女子乒乓球单打决赛中,丁宁的发球被判罚不仅影响了比赛胜负的结果,而且引发了人们对发球判罚的争议。通过在比赛录像截图中建立二维直角坐标系,对乒乓球在直角坐标系中进行定位,对丁宁两个被判发球抛球的出手角度和抛球高度进行定量研究。结果表明,丁宁被判罚的两个发球的抛球高度都大于40cm,出手角度在80o左右,反映出裁判员判罚尺度过分严格,丁宁抛球前不执拍手从远离身体向靠近身体的水平移动是被裁判认为抛球不够垂直的主要原因。同时,丁宁抛球后不执拍手臂未能从球和球网之间的空间移开存在违规风险。In Table Tennis Women's Singles Final of 2012 London Olympic Games ,the penalties of Ding Ning' s service not only affected the result of match but also caused debate on the service penalty. By building up twodimensional rectan gular coordinate system in the screenshots of video,locating de ball in the twodimensional rectangular coordinate system, a quantitative research was done about toss angles and heights of Ding Ning' s two services which were penalized. The re suits indicated that the heights Ding Ning' s services were more than 40cm,and the angles were about 80° ,reflecting that the umpire was over strict. The main reason why the umpire thought Ding Ning' s toss was not vertical is the free hand moved from far to near before toss. At the same time, after projecting the ball, Ding Ning' s free arm didn' t remove from the space between the ball and the net which has the irregularity risk.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:3.145.165.235