A mathematical model for decision-making in the classification of para-footballers with different severity of coordination impairments     

Diego Pastor  María Campayo-Piernas  Jesús Tadeo Pastor 《Journal of sports sciences》2019,37(12):1403-1410

Classification is a defining feature of Para-sport, and sports-specific classification systems determined through multidisciplinary scientific research are required, i.e., evidence-based and focused on the relationship between the impairment and the key performance determinants. Data envelopment analysis (DEA) was applied as a classification tool using a directional distance function (DDF) model. The aim of the study was to test the DEA as a possible classification tool in cerebral palsy football. We analyse the performance of 56 international para-footballers with hypertonia, ataxia or athetosis, who completed a 20-test battery with DEA models. Five of the tests are included in the model (change of direction: Illinois agility test; jumping: standing broad jump, four bounds for distance, and triple hop with the non-dominant leg; 10-m sprint/acceleration; and ball dribbling, both in a straight line and following a trajectory), showing that players with less impairment exhibit the highest efficiency. This outcome suggests that DEA models might be feasible for detecting and discriminating the performance and magnitude of impairment in cerebral palsy football, with an objective ranking of the athletes in relation to different physical performance tests. This study also provides reference scores for decision-making during classification and guidance for further research in team Paralympic sports.  相似文献   

三自由度并联式波浪补偿平台建模与仿真     

唐刚  胡超  胡雄 《上海海事大学学报》2020,41(1):20-26

鉴于船舶在波浪中的六自由度运动中,其升沉、横摇和纵摇运动对船舶工作平台上的设备影响较大,设计一种三自由度并联式波浪补偿平台来减少这种影响。通过对平台进行运动学分析,得到平台的运动学模型。利用ADAMS和Simulink建立带有控制系统时间延迟参数的虚拟样机模型,依据平台的运动学模型设计对船舶运动进行补偿的控制策略,并利用虚拟样机进行仿真,验证平台机构和相应控制策略对船舶运动的补偿效果。结果表明:当控制系统的时间延迟参数取值为1 ms时,平台对船舶升沉、横摇和纵摇运动的补偿效果分别为88.81%、95.44%和91.97%;当控制系统的时间延迟参数取值为0.1 ms时,平台对船舶升沉、横摇和纵摇运动的补偿效果分别为96.04%、99.07%和97.65%。由此可见:平台对误差有一定的包容性;可利用具有船舶运动预测功能的算法为平台提供超前的船舶运动数据或者提高控制系统的实时性来提高补偿效果。  相似文献   

Factors associated with concussion-symptom knowledge and attitudes toward concussion care seeking in a national survey of parents of middle-school children in the US     

Zachary Y. Kerr  Aliza K. Nedimyer  Melissa C. Kay  Avinash Chandran  Paula Gildner  K. Hunter Byrd  Juliet K. Haarbauer-Krupa  Johna K. Register-Mihalik 《运动与健康科学(英文)》2021,10(2):113

BackgroundDeveloping appropriate concussion prevention and management paradigms in middle school (MS) settings requires understanding parents’ general levels of concussion-related knowledge and attitudes. This study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children (aged 10–15 years).MethodsA panel of 1224 randomly selected U.S. residents, aged ≥ 18 years and identifying as parents of MS children, completed an online questionnaire capturing parental and child characteristics. The parents’ concussion-symptom knowledge was measured using 25 questions, with possible answers being “yes”, “maybe”, and “no”. Correct answers earned 2 points, “maybe” answers earned 1 point, and incorrect answers earned 0 point (range: 0–50; higher scores = better knowledge). Concussion care-seeking attitudes were also collected using five 7-point scale items (range: 5–35; higher scores = more positive attitudes). Multivariable ordinal logistic regression models identified predictors of higher scores. Models met proportional odds assumptions. Adjusted odds ratios (aORs) with 95% confidence intervals (95%CIs) (excluding 1.00) were deemed statistically significant.ResultsMedian scores were 39 (interquartile range: 32–44) for symptom knowledge and 32 (interquartile range: 28–35) for care-seeking attitude. In multivariable models, odds of better symptom knowledge were higher in women vs. men (aOR = 2.28; 95%CI: 1.71–3.05), white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.88; 95%CI: 1.42–2.49), higher parental age (10-year-increase aOR = 1.47; 95%CI: 1.26–1.71), and greater competitiveness (10%-scale-increase aOR = 1.24; 95%CI: 1.13–1.36). Odds of more positive care-seeking attitudes were higher in white/non-Hispanics vs. other racial or ethnic groups (aOR = 1.45; 95%CI: 1.06–1.99) and in older parental age (10-year-increase aOR = 1.24; 95%CI: 1.05–1.47).ConclusionCharacteristics of middle school children''s parents (e.g., sex, race or ethnicity, age) are associated with their concussion-symptom knowledge and care-seeking attitudes. Parents’ variations in concussion knowledge and attitudes warrant tailored concussion education and prevention.  相似文献   

土司体育文化在永顺县中小学推广现状的调查与分析——以土家族摆手舞为例     

向依依  郑军 《体育科技文献通报》2020,(2):24-26

为促进土司体育文化更好的开展,扩展土家摆手舞的开展范围和提高摆手舞的质量,促进土司体育的发展,提高学生身体素质和文化修养。本文采用文献资料法、问卷调查法、座谈访问法、逻辑分析法,对永顺县中小学土家摆手舞开展的现状进行调查与分析。结果认为,永顺县中小学摆手舞存在学生学习兴趣不高、对摆手舞认知不足的现象,学校也因为资金受限,体育教学场地存在教学用面积不足及地面不平整状况,多数老师靠自学和其他老师所教学习的摆手舞,体育教师认为师资分配不合理现象存在,并且多数学生认为体育教师教学动作不够规范,直接影响了摆手舞在中小学的发展。  相似文献   

稀磁半导体CdS:CO~(2+)光学吸收谱的理论计算     

陈莹  施思齐 《零陵学院学报》2001,(3)

通过对过渡族自由离子ＣＯ２＋光谱的实验值进行半经验的拟合，得到了它的３ｄ电子波函数，并利用晶体场理论，计算了 ＣｄＳ： ＣＯ２＋的光学吸收谱， 计算结果与实验值吻合很好。  相似文献   

碎石桩复合地基瑞雷波评价研究     

缪林昌  石名磊  刘松玉 《东南大学学报》2001,17(2)

低振幅的剪切波速Vs 是土层深度的函数 ,瑞雷波法对剪切波波速的评价是一种新的原位测试方法 .本文研究了瑞雷波法 ,并对碎石桩法加固液化地基的处理效果进行了评价 ,瑞雷波法检测结果与标准贯入试验结果对比相一致 ,根据对剪切波波速与标贯击数相关分析 ,提出了相关的关系式 ,瑞雷波法是一种简便、无损评价方法  相似文献   

“新工科”背景下港航专业实验教学仿真的探索与实践——以“桩基冲刷实验”为例     

沈超  王琛  付小莉  李君菡 《实验技术与管理》2021,(2):122-126

在新工科"理念引导,结构优化,模式创新"理念的倡导下,将虚拟仿真技术与传统物理模型实验相结合,对港口航道与海岸工程专业本科生实验课程进行了教学模式的创新探索。以桩基冲刷实验为例,针对现有物理模型实验中的不足,运用数值计算手段,建设"虚实结合"的实验教学平台,探索"线上线下"的教学新模式。实践表明,建设波流对桩基作用的数值仿真实验有利于夯实理论基础,提升教学内涵,拓展实验教学时间与空间,为学生的创新设计提供实践平台,激发学生自主学习热情,培养学生创新实践能力。  相似文献   

褐藻糖胶测定的影响因素及其提取的优化工艺分析     

周军明  崔艳丽  毛建卫 《科技通报》2007,23(1):37-40,45

研究了苯酚-硫酸法和氯化钡明胶比浊法分别测定褐藻糖胶中多糖和硫酸根含量的影响因素，并分析了用正交试验设计法超声波辅助提取工艺的褐藻糖胶，优化提取工艺中褐藻糖胶含量达到36．97％．硫酸根含量达到22．49％。  相似文献   

2005年3月10～12日嘉兴市寒潮大雪成因浅析     

李海军  李云泉 《科技通报》2007,23(5):641-645

分析2005年3月10～12日嘉兴市寒潮、大雪天气过程发现:强寒潮是由乌拉尔阻高东移南垮引起强冷空气南下和前期明显回温共同造成的。500 hPa南支槽前的西南暖湿气流为大雪天气提供了源源不断的水汽;物理量诊断显示,高层辐散、低层辐合和弱的不稳定能量,为大雪的产生提供了动力抬升条件;高空西南暖湿气流突然加强,近地面层有大片逆温层存在,是预报大雪的关键,为今后预报大雪起到了一定参考的作用。  相似文献   

基于知识持续管理的人才流失危机管理探讨     

樊宏  戴良铁 《科学学与科学技术管理》2005,26(3):114-117

人才流失的实质是知识流失。从知识持续管理角度来看待人才流失危机管理问题，介绍了知识持续管理的相关概念和基本假设，分析了其竞争优势，初步探讨了知识持续管理体系的开发与管理策略，为企业人才流失危机管理提供了参考依据。  相似文献