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121.
ABSTRACT

The purpose of the study was to assess the validity and inter-bike reliability of 10 Wattbike cycle ergometers, and to assess the test–retest reliability of one Wattbike. Power outputs from 100 to 1000 W were applied using a motorised calibration rig (LODE) at cadences of 70, 90, 110 and 130 rev · min?1, which created nineteen different intensities for comparison. Significant relationships (P < 0.01, r2 = 0.99) were found between each of the Wattbikes and the LODE. Each Wattbike was found to be valid and reliable and had good inter-bike agreement. Within-bike mean differences ranged from 0.0 W to 8.1 W at 300 W and 3.3 W to 19.3 W at 600 W. When taking into account the manufacturers stated measurement error for the LODE (2%), the mean differences were less than 2%. Comparisons between Wattbikes at each of the nineteen intensities gave differences from 0.6 to 25.5 W at intensities of 152 W and 983 W, respectively. There was no significant difference (P > 0.05) between the measures of power recorded in the test–retest condition. The data suggest that the Wattbike is an accurate and reliable tool for training and performance assessments, with data between Wattbikes being able to be used interchangeably.  相似文献   
122.
公允价值会计因其提供的信息相关性高、决策有用性强而受到国际会计界的高度重视。我国2006年颁布的新会计准则体系,取得了诸多方面的重要突破,其中最大的亮点在于公允价值的引入和运用。中国新会计准则引入公允价值计量属性,有其可靠的理论依据以及特定的经济背景。在公允价值的具体运用方面,则体现了一定的谨慎性特征。至于公允价值的运用能否实现准则制定当局的预期经济目的,关键在于如何保证其可靠性。  相似文献   
123.
目的: 验证TGMD-3在中国3~12岁儿童基本运动技能测试中的可靠性和有效性。方法: 选取上海、深圳、重庆、洛阳、长沙的512名3~12岁儿童为研究对象进行TGMD-3测试,对测试的难度、区分度、一致性信度、重测信度和评价者信度、结构效度进行统计检验。结果: TGMD-3的13个项目难度范围为0.27~0.78,区分度范围为0.38~0.49。每个年龄组儿童基本运动技能测试(TGMD-3)的内部一致性系数范围为0.808~0.902,其中男女生的内部一致性系数均为0.95;总体的基本运动技能评价者信度(肯德尔协同系数)w为0.944, 2值为28.331,达到显著性水平;重测检验中,移动式运动技能(组内相关系数)ICC为0.755、球类运动技能(组内相关系数)ICC为0.741、总的基本运动技能(组内相关系数)ICC为0.743,均达到了较高水平。通过探索性因子分析验证了TGMD-3的双因子结构,并通过验证性因子分析支持双因子模型(χ2(64)=103.28,p<0.001,CFI=0.960,TLI=0.952,RMSEA=0.049,SRMR=0.043)。结论: TGMD-3儿童基本运动技能测试具有良好的项目难度、区分度,以及可靠的内部一致性信度、重测信度和结构效度,对我国3~12岁儿童具有良好的适用性,可以作为我国儿童基本运动技能发展评价的有效工具。  相似文献   
124.
在广泛调查研究的基础上,指出了我国电子行业ESD(静电放电)防治技术存在着技术标准的制订与颁布滞后的问题;防静电材料与制品良莠不齐;产、学、研在ESD防治技术上存在研究力量分散、研究与开发形不成合力等问题,阐述了抓紧制订防静电技术标准与技术规范的必要性。同时对综合防治ESD、集中力量开发防静电新技术与新产品、加强静电安全管理等方面提出了意见。  相似文献   
125.
我国的皮划艇激流项目力量训练的设备仍是杠铃一类的器械,杠铃虽然是一种行之有效的训练器械,但在训练学界被认为是不符合专项力量训练要求的训练器材。研究表明,只要有有效的测试监控手段,教练员同样能够正确地评价力量训练效果,提高力量训练效率。本文的研究目的是要通过自行研制简单实用的训练测试设备及其力量训练效果评价体系,对皮划艇激流国家队运动员进行力量训练的测试与评价。  相似文献   
126.
采用ISOMED2000等速系统检测优秀散打运动员膝、肘关节肌群的生物力学特征,分析优秀散打运动员站位攻防动作技术.在进攻训练中伸膝关节速度达到300°/s,能充分发挥运动员小腿伸肌群的爆发能力;采用300°/s的速度可以快速屈小腿,有利于运动员快速回防,为再次打击对方在时间上创造了条件;在站位时,膝关节角度保持157.3°~160.1°,小腿屈肌群离心爆发能力强,有利于运动员调整自身的身体姿势,避开对方的快速进攻.在进攻训练中应使肘关节速度达到300°/s,能充分发挥运动员前臂伸肌群的爆发能力.肘关节角度在81°~86°的范围,有利于运动员快速出拳,打击对方.以240°/s的速度屈肘,能充分发挥运动员前臂屈肌群的爆发能力,有利于运动员快速回防.在防守训练中,肘关节角度在78°~85°的范围内,对运动员快速回防,抵御时方快速、重拳的进攻是有利的;肘关节角度在128°~137°的范围内,可远距离隔挡对方,阻击对方的快速进攻.  相似文献   
127.
本文主要从重视概率论中常见相关分布、数理统计的概念、基本思想和难点四个方面探讨了如何搞好数理统计的教学。  相似文献   
128.
The measurement community needs to better understand how to interact with the media to effectively disseminate important findings from educational testing efforts. To this end, the current paper will review media coverage of educational testing and related issues and elaborate on areas of concern and opportunities for improved communication between measurement professionals and the media. Common misinterpretations of test results and measurement concepts will be discussed and suggestions for the clearer presentation and explanation of such information will be offered. Also, practical advice and strategies for handling different types of interactions with the media will be provided. The implications of focusing on this topic in the measurement profession and the inherent public value of this focus are highlighted throughout the paper.  相似文献   
129.
Previous research has established that SAT scores and high school grade point average (HSGPA) differ in their predictive power and in the size of mean differences across racial/ethnic groups. However, the SAT is scaled nationally across all test takers while HSGPA is scaled locally within a school. In this study, the researchers propose that this difference in how SAT scores and HSGPA are scaled partially explains differences in validity and subgroup differences. Using a large data set consisting of 170,390 students each of whom matriculated at one of 114 separate colleges, the researchers find that awarding SAT scores by ranking SAT within a high school generally results in substantial reduction in the size of subgroup mean differences for this predictor. However, validity for predicting first‐year GPA is also reduced by a small amount. Conversely, placing HSGPA onto a nationally normed metric through the use of multiple regression procedures results in a moderate increase in the size of subgroup mean differences, while also producing a small increase in validity. Taken together, these findings suggest that differences in predictor scaling can partially explain differences in the size of subgroup mean differences between HSGPA and SAT scores and have implications for predictive power.  相似文献   
130.
There is currently a strong belief in accountability as a policy of action and standardized testing has been implemented in several countries. This article examines tensions that occur in meetings when primary school teachers in Norway discuss national testing, and how these are handled. In particular, tensions revolve around what is seen as internal (teachers' everyday work) and external (policies and practices outside the main frame of teaching). Even though national testing is mainly seen as external to teachers' work, teachers involve in boundary work and reshape professional discourse in order to create relevance and maintain legitimacy following new expectations.  相似文献   
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