《军人体育锻炼标准》对解放军信息工程大学学生身体素质及机能状况影响的分析研究

通过对我校部分学生达军标的三年追踪测试,实验结果表明,开展达军标活动,促进我校学生的身体素质、机能状态的改善和提高.经过几年的实验研究,结合我校的实际情况研究和编制出<解放军信息工程大学学生达军标跟踪检测管理系统>,为今后学校或其它军事技术院校的达军标和体育活动的开展提供了理论和实践的参考.     

项目反应理论在运动心理测量领域的运用与发展

:IRT模式是否可以用来评价心理运动技能 ,许多学者已经对传统的“技能测量”模式提出了异议 ,在此基础上简述了测量理论的发展和 IRT模式的原理 ,分析了 IRT在运动中的有用性及弊端 ,探讨了 IRT在运动心理行为测量中的未来发展方向     

非精英篮球运动员Yo Yo间歇耐力跑和运球Yo Yo跑与最大摄氧量的关系

探讨了非精英男子篮球运动员Yo-Yo间歇耐力跑测试成绩、运球Yo-Yo间歇耐力跑测试成绩的再测信度,以及与最大摄氧量的关系。受试者为31名年龄13—18岁的非精英篮球运动员。结果显示Yo-Yo跑测试速度、运球Yo-Yo跑测试速度的再测信度和典型误分别为ICC=0.76(p=0.012),TE=0.31,ICC=0.90(p=0.000 1),TE=0.23。最大摄氧量与Yo-Yo跑测试速度、运球Yo-Yo跑测试速度相关度分别为r=0.54(p=0.01),r=0.60(p=0.002)。运球Yo-Yo跑速度与Yo-Yo跑速度相关度为r=0.72(p=0.000 1),第二次运球Yo-Yo跑和Yo-Yo跑测试成绩的一致性界限范围是(-2.50,-0.93)。结果说明Yo-Yo跑测试成绩、运球Yo-Yo跑测试成绩1周内进行重测,具有较高的再现性,且Yo-Yo跑测试成绩和运球Yo-Yo跑测试成绩与最大摄氧量都具有中度相关,Yo-Yo跑测试成绩与运球Yo-Yo跑测试成绩高度显著相关。     

蚀变岩在三向应力状态下的力学及变形特性研究

实际工程中的岩体总是处于三向应力状态下,研究三向应力状态下岩体强度和变形特性,对于岩土工程的设计施工具有重要意义。此次研究以某水电站工程项目为依托,对水电站左右坝肩的蚀变岩做了大量的常规三轴压缩试验。在此基础上,经过分析处理,得出了蚀变岩的抗剪强度指标与围压的相关关系,建立了应力-应变关系曲线的分阶段本构模型。在蚀变岩的力学特性研究方面进行了有益的探索,为工程设计和稳定性分析提供了重要的技术支撑。     

Determination of peak cardiorespiratory fitness parameters in children: which averaging method should we use?

The purpose of this study was to identify which averaging methods most accurately measures peak cardiorespiratory fitness (CRF) parameters [peak O₂ uptake (VO₂), peak O₂pulse and peak respiratory exchange ratio (RER)] in a sample of healthy children and adolescents. In this cross-sectional multicenter study, we recruited 278 healthy children aged 12–17 years. We compared the mean peak value of three CRF parameters using the recommended averaging methods (30-second block average) with alternative averaging methods such as moving averages or shorter smoothing periods. We also assessed averaging methods for accuracy by individually reviewing breath-by-breath scatter plots. The 30-second block average method resulted in a lower mean peak VO₂ and in an increased proportion of underestimated peak values. Using a 30-second moving average significantly increased mean peak values which increased accuracy. Similar results were found for peak RER and peak O₂pulse. In conclusion, the currently recommended averaging method (30-second block average) increased the risk of misinterpretation of peak CRF values in children. Using a moving average approach decreased misinterpretation and increased accuracy.     

Evaluation and application of an efficient plant DNA extraction protocol for laboratory and field testing

Nucleic acids in plant tissue lysates can be captured quickly by a cellulose filter paper and prepared for amplification after a quick purification.In this study,a published filter paper strip method was modified by sticking the filter paper on a polyvinyl chloride resin(PVC)sheet.This modified method is named EZ-D,for EASY DNA extraction.Compared with the original cetyl trimethylammonium bromide(CTAB)method,DNA extracted by EZ-D is more efficient in polymerase chain reaction(PCR)amplification due to the more stable performance of the EZ-D stick.The EZ-D method is also faster,easier,and cheaper.PCR analyses showed that DNA extracted from several types of plant tissues by EZ-D was appropriate for specific identification of biological samples.A regular PCR reaction can detect the EZ-D-extracted DNA template at concentration as low as 0.1 ng/μL.Evaluation of the EZ-D showed that DNA extracts could be successfully amplified by PCR reaction for DNA fragments up to 3000 bp in length and up to 80%in GC content.EZ-D was successfully used for DNA extraction from a variety of plant species and plant tissues.Moreover,when EZ-D was combined with the loop-mediated isothermal amplification(LAMP)method,DNA identification of biological samples could be achieved without the need for specialized equipment.As an optimized DNA purification method,EZ-D shows great advantages in application and can be used widely in laboratories where equipment is limited and rapid results are required.     

跨年级小学生数学学力认知诊断测验的IRT垂直等值分析

本研究采用“共同题?锚测验”设计,使用R语言ltm程序包中的IRT两参数模型进行各年级小学生数学学力认知诊断测验和被试参数的估计,并使用equateIRT程序包进行跨年级小学生数学学力认知诊断测验各项参数的等值转换。结果表明,等值转换后各年级测验的题目难度和小学生数学学力均随年级增长而逐渐递增,不同学校、民族、性别学生的数学学力发展差异性特征均与理论假设相符。本研究验证了采用IRT垂直等值方法构建跨年级小学生数学学力发展水平垂直量表的可行性,为制定系统性补救教学方案和自适应题库建设提供了必要的实证证据。     

Prior knowledge in mathematics and study success in engineering: informational value of learner data collected from a web-based pre-course

The article describes the development and evaluation of a web-based pre-course in mathematics, delivered to four cohorts of engineering students at a German university. Based on demographic, personal, and learning-related data relationships between students’ preconditions, their learning gains in the pre-course, and study success in the degree programme were analysed. The results support the existing literature in that domain-related prior knowledge and secondary school achievement play a dominant role regarding study success in engineering. The analyses also showed that the influence of cognitive predictors could only be compensated for by a strong learner engagement. At-risk students with high pre-course learning gains showed significantly better first-year performance. The number of self-tests a student attempted was positively related to pre-course learning gains and even to first-year performance, suggesting that this variable is a good indicator of student engagement.     

对方言区普通话水平测试格局的思考

普通话水平测试目前的格局主要是由单双音节、朗读、说话四部分构成，但随着测试工作的全面铺开，尤其是在重方言区，这样的格局已经不太能满足日益扩大的待测群体。本文针对方言区目前待测对象的语音面貌提出建立一种过渡模式，以适应当前方言区的普通话水平测试。     

On the Performance of Semi- and Nonparametric Item Response Functions in Computer Adaptive Tests

Large-scale assessments often use a computer adaptive test (CAT) for selection of items and for scoring respondents. Such tests often assume a parametric form for the relationship between item responses and the underlying construct. Although semi- and nonparametric response functions could be used, there is scant research on their performance in a CAT. In this work, we compare parametric response functions versus those estimated using kernel smoothing and a logistic function of a monotonic polynomial. Monotonic polynomial items can be used with traditional CAT item selection algorithms that use analytical derivatives. We compared these approaches in CAT simulations with a variety of item selection algorithms. Our simulations also varied the features of the calibration and item pool: sample size, the presence of missing data, and the percentage of nonstandard items. In general, the results support the use of semi- and nonparametric item response functions in a CAT.