Reprints from the Research Quarterly

Abstract

The purpose of this study was to determine the effects of intensified physical education sessions on adolescents ages 11–16 years. They were divided into two experimental groups—high-intensity running group (HIRG) and high-intensity jumping group (HIJG)—and a control group (C). During the sessions, heart rate (HR) was monitored. There was no significant difference between mean HR for HIRG and HIJG, while the mean HR was significantly lower for C (p < .001). For both HIRG and HIJG, the mean HR was significantly higher for girls than for boys (p < .001). Our results suggested that these intensified physical education lessons require a high percentage of maximal HR in adolescents and can be used to improve aerobic fitness.     

健身健美操对大学生最大摄氧量的影响研究——以武汉科技大学为例

运用抽样调查、实验和比较研究法研究武汉科技大学学生的最大摄氧量。结论显示:健身健美操能显著改善大学生的心血管机能;足球、篮球、羽毛球和网球项目相比,改善效果更显著;对女生心血管机能的改善程度大于男生。     

梁横向振动问题的特征值的一种算法

本文考虑计算梁横向振动问题的特征值的近似值的一种算法 .主要结果的证明运用变分公式 .首先利用Cauchy不等式证明了一个基本不等式 ;其次采用Galerkin方法来构造适当的基函数 ,并利用Cauchy不等式给出了其特征值计算的误差估计式 ;最后得到计算梁横向振动问题的特征值的近似值的算法 ,而且可以用第n次近似值来估计第n - 1次的近似值的精确度 .随着n的增大 ,特征值λk 的精确度逐步提高 ,只要适当选取n ,就可以求得所要精确度的特征值的近似值 .这个算法具有广泛的实用价值和理论价值     

求解奇异线性方程组的一类推广的Cramer法则

任意给定方阵A,首先给出了A的群逆、Dazin逆的行列式表示,借此导出了求一类约束线性方程组的解的行列式公式,并应用文献[8]的结果,得到了求不相容线性方程组极小范数最小二乘解的行列式公式.当方程组为非奇异线性方程组时,所得行列式公式均可化为经典的Cramer法则,从而将Cramer法则在奇异线性方程组领域做了新的形式的推广.     

对称三对角矩阵的QL方法论

QL(QR) method is an efficient method to find eigenvalues of a matrix. Especially we use QL(QR) method to find eigenvalues of a symmetric tridiagonal matrix. In this case it only costs O( n^2) flops, to find all eigenvalues. So it is one of the most efficient method for symmetric tridiagonal matrices. Many experts have researched it. Even the method is mature, it still has many problems need to be researched. We put forward five problems here. They are: (1) Convergence and convergence rate; (2) The convergence of diagonal elements; (3) Shift designed to produce the eigenvalues in monotone order; (4) QL algorithm with multi-shift; (5) Error bound. We intoduce our works on these problems, some of them were published and some are new.     

复矩阵稳定度的充分判据

对于给定的n阶复矩阵A，给出了几个直接由A的元素确定其稳定的充分判据，最后给出的例子表明，此方法简捷，具有一定的实用性。     

Maximal Criterion Validity and Scale Criterion Validity: A Latent Variable Modeling Approach for Examining Their Difference

This article studies the difference between the criterion validity coefficient of the widely used overall scale score for a unidimensional multicomponent measuring instrument and the maximal criterion validity coefficient that is achievable with a linear combination of its components. A necessary and sufficient condition of their identity is presented in the case of measurement errors being uncorrelated among themselves and with a used criterion. An upper bound of the difference in these validity coefficients is provided, indicating that it cannot exceed the discrepancy between the maximal reliability and composite reliability indexes. A readily applicable latent variable modeling procedure is discussed that can be used for point and interval estimation of the difference between the maximal and scale criterion validity coefficients. The outlined method is illustrated with a numerical example.     

一个具有奇异非线性项的三阶两点特征值问题

研究了非线性三阶两点边值问题u（t）＋λ[h（t）f（t,u（t））＋g（t,u（t））]=0,00,此问题存在一个正解.     

伪黎曼空间L_p~(n+p)中紧致类空子流形上的积分不等式

设L_p~(n+p)是截面曲率KL满足条件KL≥a(a是实数)的伪黎曼空间,Mn(n≥2)是L_p~(n+p)中的紧致类空子流形.本文得到了Mn上Laplacian算子的第一特征值的两个积分不等式.     

关于强duo模的推广

本文给出了强duo模的一个推广——极大强duo模,研究了极大强duo模的一些刻画及性质,并且证明了在半单模的条件下,极大强duo模与强duo模是等价的.