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41.
利用BPA软件以新英格兰10机39节点系统为例,验证模糊C均值聚类法判别同调机群的正确性。  相似文献   
42.
根据奈达的功能对等理论,结合法律翻译研究者的理论和观点,理论联系实际,提出在翻译英文规定性法律文本中的同义词时,可以采用分别翻译和联合统一翻译的处理方式,实现法律文本翻译准确性的基本原则,达到形式、内容和效力等同的法律文本翻译标准。  相似文献   
43.
以学生评价为视角研究高校研究生导师问题行为,通过调查发现研究生导师问题行为由情感暴力、放任敷衍、品德不良三个方面构成,并表现出以下特点:(1)总体上教师的教育行为是比较符合职业道德要求和教学规律的,教师问题行为情况不严重,但是情感暴力、放任敷衍、品德不良三个方面的问题行为发生率比较高。(2)当前研究生导师问题行为存在导师类型和学科差异。博士生导师的问题行为显著高于硕士生导师;理科、工科和其它学科的研究生导师问题行为显著高于文科研究生导师。在此基础上,提出预防和矫正研究生导师问题行为,提高研究生培养质量的对策建议。  相似文献   
44.
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics.  相似文献   
45.
Muscle imbalance and deficit are key parameters for guiding rehabilitation and sports sessions and avoiding injuries. However, the high cost and non-portable nature of most instruments employed for muscle strength assessment frequently hamper an affordable evaluation in field conditions. This study evaluated the validity and reliability of a low-cost digital dynamometer to assess the maximal isometric strength of upper limb muscles. Fourteen physically active volunteers performed the main movements of the upper limb at maximal isometric strength: flexion-extension, internal-external rotation and abduction-adduction of the shoulder; and flexion-extension of both elbow and wrist. Validity was examined by comparing the strength values from the low-cost digital dynamometer and those measured by an isokinetic dynamometer, assumed as the gold standard. The correlation between both devices was perfect (r > 0.913), while Bland-Altman plots showed absolute agreement between both devices, the maximum range of the values of bias was ?0.99–1.00 N in wrist extension. Inter-tester and intra-tester reliability were excellent for all movements (ICC ≥ 0.855). The low-cost digital dynamometer showed strong validity and excellent reliability in assessing maximal isometric strength during the main movements of the upper limb. Professionals may use it for an affordable isometric muscle strength assessment in field situations.  相似文献   
46.
有规律的体育锻炼对人们的身心健康具有积极的促进作用,而社会支持是影响锻炼行为的重要相关因素。因此本研究的目的在于编制和检验锻炼社会支持量表。通过结合现有研究文献和质性研究,确立了初测量表,并通过两轮定量研究,应用探索性和验证性因子分析,信度分析以及校标效度检验对该量表进行了标准化的信效度检验。结果表明锻炼社会支持量表由4个因子构成,即情感性支持、信息性支持、工具性支持、同伴性支持,共24个条目。统计分析显示,量表具有良好的结构效度、内部一致性、重测信度和校标效度。锻炼社会支持量表符合我国文化背景,可以作为在中国人群中进行锻炼社会支持测量的工具。  相似文献   
47.
The purpose of this study was to compare the validity and reliability of three short physical activity self-report instruments to determine their potential for use with university student populations. The participants (N = 155; 44.5% male; 22.9 ± 5.13 years) wore an accelerometer for 9 consecutive days and completed a single-item measure, the a brief two item measure and the International Physical Activity Questionnaire—Short Form questionnaires on day 1 and 9. Correlations between self-reported and accelerometer derived moderate-to-vigorous physical activity levels were moderate for the International Physical Activity Questionnaire—Short Form, while poor for the single-item measure and the a brief two item measure. The agreement level was high with the International Physical Activity Questionnaire—Short Form (77.4%) and moderate for both the single-item measure (45.2 %) and a brief two item measure (44.5 %). The intraclass correlations between the two administrations were moderate to strong across all measures (0.52–0.70) in 133 participants. The International Physical Activity Questionnaire—Short Form is the most suitable of these three self-report instruments for use with this population due to higher correlations and levels of agreement with accelerometry.  相似文献   
48.
This study examined the psychometric properties of a questionnaire developed with the guidance of the socialization model of child behaviour to understand modifiable correlates of toddlers’ physical activity and sedentary behaviour. Findings are based on 118 parents (33.7 ± 4.9 years; 86% female) of toddlers (19.3 ± 2.7 months; 48% female) from Edmonton, Canada in The Parents’ Role in Establishing healthy Physical activity and Sedentary behaviour habits study (PREPS). The PREPS questionnaire encompassed 21 variables across the constructs of the socialization model of child behaviour. Of the nine variables assessed for internal consistency reliability, eight had good (α ≥ 0.70) reliability. Of the 15 continuous variables assessed for 1-week test–retest reliability, 10 had moderate (intra-class correlation = 0.50–0.74) and 5 had good (intra-class correlation ≥ 0.75) reliability. Of the six categorical variables assessed for 1-week test–retest reliability, two had fair (К = 0.21–0.40), one had moderate (К = 0.41–0.60), one had substantial (К = 0.61–0.80), and two had almost perfect (К = 0.81–1.00) reliability. Of the 12 sedentary behaviour variables assessed for convergent validity, 7 were significantly correlated with children’s screen time, of which three were small (r ≤ 0.29), two were medium (r = 0.30–0.49), and two were large (r ≥ 0.50) effect sizes.  相似文献   
49.
A study was conducted to assess the validity of the Global Physical Activity Questionnaire (GPAQ) for measuring sedentary behaviour (SB) in the Chilean adult population. About 217 adults (93/124 male/female, 43.8 ± 15.75 years) who were randomly selected during National Health Survey 2009–2010 completed the protocol. The participants wore an ActiGraph GT3X (AG) for 7 consecutive days and then completed the GPAQ (single-item question for measuring time spent sitting in a usual day). Validity was examined using Spearman’s correlation, mean bias and limits of agreement (LoA), with AG (vertical axis <100 counts · min?1) as the reference standard for estimates of SB in bouts of 1 (AG1), 5 (AG5) and 10 (AG10) min. Agreement between the GPAQ and AG for classifying data into quartiles and tertiles was assessed with kappa method. The GPAQ showed fair correlation with AG1, AG5 and AG10 (range = 0.23–0.26), with large mean biases (range = ?293.9, ?76.12 min · day?1). Agreement between the GPAQ and AG1, AG5 and AG10 was poor for categorising time spent in SB into tertiles and quartiles. The single question from the GPAQ has shown fair validity for measuring SB and poor ability for correctly classifying individuals into tertiles or quartiles of SB in a Chilean population.  相似文献   
50.
Research on children’s physical self-concept (PSC) is increasingly recognised as an important field of psychology. However, there is a lack of instruments suitable for younger children at elementary school age. In the present study, a short German 21-item Physical Self-Concept-Questionnaire for children (PSCQ-C) was tested measuring seven specific facets of elementary school children’s PSC (strength, endurance, speed, flexibility, coordination, physical appearance, global sport competence). A number of 770 elementary school children aged 8–12 years completed the PSCQ-C. Results showed good psychometric properties and high reliabilities of the seven scales. Confirmatory factor analysis revealed that the presumed 7-factor model fitted the data best compared to a global 1- and 2-factor model. Also, full measurement invariance was strongly established. Correlations among the seven scales were mainly moderate. Gender differences were suggestive of developmental trends that are consistent with prior studies. These results provide support that the PSCQ-C is a confidential instrument with sound psychometric properties measuring seven specific facets of elementary school children’s PSC.  相似文献   
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