Visual function,performance, and processing of basketball players vs. sedentary individuals     

Jesús Vera  Raimundo Jimnez  David Crdenas  Beatriz Redondo  Jos Antonio García 《运动与健康科学(英文)》2020,9(6):587-594

BackgroundAthletes tend to have better visuo-motor performance than do sedentary individuals. However, several basic visual-function and perceptual parameters remain unexplored to date. In this study, we investigated whether differences exist in visual function, performance, and processing between basketball players and individuals without a sport-involvement background.MethodsA total of 33 healthy men with no visual impairment or pathology were divided into 2 groups, depending on the involvement in sport (semi-professional basketball players and sedentary individuals). We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level, and we checked their visual function, performance, and processing through an extended battery of optometric tests.ResultsThe 2 groups differed in resting heart-rate variability parameters (p < 0.001), confirming their dissimilarities in regular time practising sports per week. The basketball players showed a closer breakpoint and recovery nearpoint of convergence, a higher fusional-vergence rate, better discriminability halos, and better eye–hand coordination (all p values < 0.05).ConclusionThese results show evidence that athletes, basketball players in this case, exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds, suggesting an improvement due to the systematic involvement of those skills during basketball practice.  相似文献   

Health-related fitness knowledge growth in middle school years: Individual- and school-level correlates     

Xihe Zhu  Justin A. Haegele  Haichun Sun 《运动与健康科学(英文)》2020,9(6):664-669

BackgroundHealth-related fitness knowledge (HRFK) has been an essential concept for many health and physical education programs. There has been limited understanding and longitudinal investigation on HRFK growth. This longitudinal study examined HRFK growth and its individual- and school-level correlates in middle school years under 1 curriculum condition: Five for Life.MethodsParticipants were 12,044 students from 47 middle schools. Data were collected at both individual/participant and school/institution levels. Individual-level variables included gender, grade, and HRFK test scores. School-level variables included percentage of students receiving free and reduced meals (FARM), student-to-faculty ratio for physical education, and school academic performance (SAP). We used hierarchical linear modeling to examine HRFK 3-year growth in relation to individual- and school-level correlates.ResultsThe average HRFK score at 6th grade for females was 42.81% ± 1.32%. The predicted HRFK growth was 17.06% ± 1.02% per year, holding other factors constant. A 1-standard deviation increase in FARM correlated with a 14.68%-point decrease in predicted test score (p = 0.02). A 1-standard deviation increase in SAP was associated with an 11.90%-point increase in HRFK score. Males had a significantly lower growth rate than females during the middle school years (0.78%/year, p = 0.02).ConclusionThe result showed that both individual- and school-level variables such as gender, FARM, and SAP influenced HRFK growth. Educators should heed gender differences in growth curves and recognize the correlates of school-level variables.  相似文献   

我国高尔夫球奥运选手与世界优秀选手一号木数据对比分析     

赵紫龙 《河北体育学院学报》2020,34(6):85-90

采用文献资料法、实地考察法、数理统计法和对比分析法，对我国奥运选手和世界优秀选手的一号木数据进行分析。发现，在实地考察的球洞中，世界优秀选手全四轮均使用一号木开球，而我国男子选手则是一号木、三号木交替开球，可能是由于对自身一号木开球技术不够自信；我国男子选手的一号木平均开球距离、上球道率较世界优秀选手均差距较大；我国女子选手的一号木平均开球距离与世界优秀选手较为接近，但上球道率有待提高。建议，男子选手加强开球距离和上球道率的训练，女子选手加强上球道率的训练；冯珊珊进一步提升开球距离；在比赛前要对场地进行多次熟悉，找到合适的开球策略。  相似文献   

马克思再生产模型中的最高、最低积累率     

陶为群 《巢湖学院学报》2011,(4):25-31

马克思的两部类再生产模型中的各部类和全社会最高与最低积累率问题,是尚未获得完满解决的难点问题。本文运用单调函数的性质和求函数最大、最小值方法,通过解析,给出了静态意义下的各部类和全社会最高及最低积累率与两个部类结构参数的函数关系式。并且引用和借鉴《资本论》中的举例,对给出的函数关系式做了算例验证。  相似文献   

高等院校评价教师系统框架之数据来源分析     

郝春林  高俊玉 《教育教学论坛》2020,(13):26-27

高校评教是高校教育教学管理中的重要一环。文章针对目前已有的评教系统数据源单一、数据使用不充分、教师反馈不及时、师生互动性欠佳、学生评教积极性不高等现状,提出了一个高校评教系统新框架,以评教结果的使用范围为目的,反推出评教数据来源应具备多次性和多样性。每学期多次评教,实现教师与学生的互动,促进学生评教积极性,促进教师及时改进教学方法。评教人员除了学生之外,还应包括督导专家和往届生。  相似文献   

国有商业银行如何应对利率市场化改革的风险   总被引：1，自引：0，他引：1  

冯友钊  贺建清 《衡水学院学报》2004,6(3):44-46

利率市场化改革给国有商业银行的经营带来更大的风险,如:竞争风险、信用风险、利率风险、流动性风险等。如何趋利避害,应对风险,笔者认为从4个方面入手:产权制度改革;经营观念的转变;业务上由传统业务向中间业务、表外业务转变,由分业经营向混业经营转变;风险的全面管理。  相似文献   

An Improvement of MPEG-4 Rate Control Algorithm     

鲁照华李华  刘继兴 《天津大学学报(英文版)》2005,11(1):40-43

Frame skipping in low bit video coding could significantly reduce the visual quality of reconstructed video. At the same time, if the complexity of the video sequence remains high for a long period, then driving up the long term average bit rate, the only resort of MPEG-4 Q2 rate control algorithm results in using a high quantization scale, which shows a poor visual quality of the reconstructed video. This paper analyzes the main causes of frame skipping in current MPEG-4 frame rate control scheme, and presents a new rate control algorithm based on the quadratic R-D model over a CBR channel. Key features of the present work are. 1) the bits allocated to each P-frame or B-frame are in proportion to its distance from the end of this GOP, i.e. more bits are allocated to the frames that are nearer to their reference Ⅰ -frame: 2) the target buffer level is changeable in the GOP, at the end of each GOP( five P-frames or B-frames), the target buffer level is linearly reduced from 1/2 to 1/4 of buffer size, to other frames, the target buffer level is set to 1/2 of buffer size: 3 ) a selective and judicious use of the reduced resolution mode, in addition to a modulation of the quantization scale parameter, is to control the average long term bit rate. Experimental results with different video sequences of varied complexity, encoded at low bit rates show better efficacy of the proposed algorithm than MPEG-4 Q2 rate control scheme, and the experimental results also show that the improved algorithm has significantly reduced the number of frame skipping, increased the overall PSNR, and improved the perceptual quality.  相似文献   

福建省科技进步贡献率的测算和结果分析     

王倩  胡日东 《三明学院学报》2004,21(2):143-148

应用索洛余值法对福建全省经济增长及科技进步贡献率进行测算,计算出科技进步和其他要素对经济增长的贡献份额,并对各地市的数据进行横向比较,得出福建省各地市科技进步的差距。  相似文献   

Effect of acquisition rates on off‐task behavior of kindergarten students while learning sight words     

Matthew K. Burns  Lisa N. Aguilar  Kristy Warmbold‐Brann  June L. Preast  Crystal N. Taylor 《Psychology in the schools》2021,58(1):5-17

Assessing a student's acquisition rates (ARs) is a reliable way to determine how many new words should be taught in one lesson without reducing retention. Exceeding a student's AR can result in frustration and problem behaviors. The purpose of this study was to examine the effect of AR on the off‐task behavior of kindergarten students while participating in a commonly used sight‐word instruction video. Participants included 39 kindergarten students whose ARs were assessed before showing the sight‐word video. Behavior was measured as on‐ and off‐task using momentary time‐sampling with 10‐s intervals. Results indicated that students' time off task increased after exceeding their ARs, with a noticeable immediate increase. The implications and limitations of these results are discussed.  相似文献   

“双一流”建设背景下高等教育高质量发展指标研究     

张丽 《天津市教科院学报》2021,(2):43-49

创新驱动高质量发展是高等教育发展的未来,也是“双一流”建设质量发展指标研究的关键。在筛选和找出“双一流”建设质量的关键绩效指标(KPI)的基础上,提出了三个步骤的技术路线:一是分析影响因素,且按其重要性进行排列;二是按重要程度不同而精选出关键影响要素和绩效指标;三是更加重视整体研究和相关性研究,促进“以评促建”功能的实现。最后,对其中几个关键绩效指标(KPI)进行较为详细的诠释,包括高等教育毛入学率、生师比、学术声誉调查等。  相似文献