跳远运动员助跑速度感知能力训练对踏板准确性影响的实验研究

通过问卷调查和实验法对跳远运动员助跑踏板准确性和影响跳远运动员助跑速度感知能力的主要因素进行理论与逻辑分析,根据跳远专项特点优选出9种训练方法,实验组采用优选训练手段,对照组采用常用普通训练手段。在严格控制训练过程及训练条件下,进行为期16周的速度感知能力的训练,保证两组只在训练内容方面不同外,其余方面保持一致。实验后对实验组和对照组再次进行踏板准确性和跳远成绩的测定,结果表明:实验后实验组与对照组的跳远成绩与踏板准确性具有明显的差异性。     

单源三站外辐射源雷达目标探测性能

论述全向外辐射源雷达空中目标探测系统的主要问题及系统体制损失。针对单源单站（SISO）和单源三站（SITO）两种工作方式,在接收天线阵元数相同的情况下分析探测距离和定位精度。在单源三站条件下推导直角坐标系中的目标速度矢量表达式,并分析速度测量精度。研究结果表明,在一定条件下,单源三站组网方式的空间覆盖范围与单源单站相当,且具有平面定位精度较高,可获得目标速度矢量和技术实现难度小的特点。     

理解监测及其准确性

理解监测是元理解的重要组成，是学习者对自身理解状态进行判断的过程，受到研究者的广泛关注。已有研究对理解监测的产生机制、准确性及其提高策略进行了探讨。从社会文化和文本阅读加工角度继续深入探索是今后研究的主要方向。     

略论运动生物力学的研究方法与测量技术

文章认为:1,仅依靠牛顿分析力学的研究方法,运动生物力学只能停留在“研究人体机械运动规律”的水平,“走出系统”的研究方法适合于对活体系统的生物力学研究;2,“理论模型”需数据支持才具有应用价值,“数据模型”需相应的数学化才具有理论意义;3,活体运动过程的测量应建立参数采集与测量的标准化和参数分析与评价的专家系统;4,应界定常规参数和敏感参数,并区别参数间的平行关系和因果关系,测量精度的提高主要应依靠测量参数数字化过程的分析方法的进步。     

体操运动员前臂运动特征及其发展特点的研究

采用直观半圆仪,对我国441名体操运动员和563名青少年儿童的前臂屈伸复制运动误差值作了测定和比较分析等研究,结果发现,就这个非专业性的和极为普通的动作——前臂屈伸运动的准确性来讲,在运动等级不同的体操运动员之间以及体操运动员与同年龄的普通人之间,都存在明显的差别。而且,这种运动准确性较高者,学习基本体操动作的成效优于准确性较低者。这种运动的准确性在7～11岁期间提高最快,12～22岁时呈波浪式的发展状态;在体操运动训练的作用下,这种运动的准确性,在9～13岁加速提高,而且,随后的波浪式变化明显减小。     

Lifesource XL-18 pedometer for measuring steps under controlled and free-living conditions

The primary aim was to examine the criterion and construct validity and test–retest reliability of the Lifesource XL-18 pedometer (A&D Medical, Toronto, ON, Canada) for measuring steps under controlled and free-living activities. The influence of body mass index, waist size and walking speed on the criterion validity of XL-18 was also explored. Forty adults (35–74 years) performed a 6-min walk test in the controlled condition, and the criterion validity of XL-18 was assessed by comparing it to steps counted manually. Thirty-five adults participated in the free-living condition and the construct validity of XL-18 was assessed by comparing it to Yamax SW-200 (YAMAX Health & Sports, Inc., San Antonio, TX, USA). During the controlled condition, XL-18 did not significantly differ from criterion (P > 0.05) and no systematic error was found using Bland–Altman analysis. The accuracy of XL-18 decreased with slower walking speed (P = 0.001). During the free-living condition, Bland–Altman analysis revealed that XL-18 overestimated daily steps by 327 ± 118 than Yamax (P = 0.004). However, the absolute percent error (APE) (6.5 ± 0.58%) was still within an acceptable range. XL-18 did not differ statistically between pant pockets. XL-18 is suitable for measuring steps in controlled and free-living conditions. However, caution may be required when interpreting the steps recorded under slower speeds and free-living conditions.     

基于BP网络的有教师分类算法及应用

介绍BP神经网络的结构及相关算法,并通过实验比较不同情况下对BP神经网络的收敛速度与分类精度的影响。实验表明,合适的参数设置能提高BP神经网络算法的分类精度。     

女性主义译者主体性在元认知心理作用下的体现

元认知是外语学习和外语教学中常用的一种策略。翻译作为语言学习的一部分,其过程也要受到元认知心理的影响。在文学作品翻译中,女性主义译者在这种心理作用下,通过语际之间的转换,实现对原文的重写,体现她们的社会地位和政治主张,并从翻译作品的选择、翻译标准的重写和翻译策略的运用等方面充分体现她们在翻译中的主体性。     

焊接机器人模块化工装组夹及复现工艺研究

焊接机器人工装组夹及产品复现在生产中是极为重要的,文章针对焊接机器人对工装精确度的要求,采用棋盘方格定位法和复现工艺,实现了焊接工装和机器人重复定位精度的要求,在多种产品上得到应用推广。     

The Domain-Specificity of Elementary School Teachers’ Judgment Accuracy

Teachers’ diagnostic competence for accurately judging students’ achievement is essential for instructional practice and professional decisions. To promote their judgment accuracy, it is important to know if this is a general or domain-specific skill. We investigated teachers’ judgment accuracy in German language (one subdomain: reading) and mathematics (two subdomains: geometry; stochastics) and examined differences across domains (i.e., German and mathematics) and across subdomains (reading; geometry; stochastics). We examined the judgment accuracy of 59 German elementary school teachers who teach both German and mathematics, judging the achievement of 1227 students in the three subdomains. We conducted multilevel analyses with a subsample of 39 teachers and 787 students and calculated different accuracy components (i.e., rank, level, and differentiation) to examine the comparability of our results. In line with prior research, findings revealed that teachers’ judgments were fairly accurate. However, there were significant differences between teachers’ average judgment accuracy in different subdomains (between-person comparisons) and no or only a weak relation between individual teachers’ judgment accuracy in different subdomains (within-person comparisons). Findings support the notion that teachers’ judgment accuracy of student achievement is domain-specific with respect to the investigated subdomains. Practical implications for the promotion of teacher judgment accuracy are discussed.