初中生物理实验操作能力及品质的比较研究

物理实验操作能力是物理实验能力的核心。加强对学生物理实验操作能力的发展研究，能使教师了解学生实验操作能力的本质，把握学生物理实验操作能力的发展规律，并对学生实验操作能力的培养提供依据。本文主要研究初二、初三两年级物理实验操作能力及各品质的比较。经研究得出初三学生操作能力及各品质都要好于初二学生。     

THE GROWTH OF THE VOID IN A HYPERELASTIC RECTANOULAR PLATE UNDERA UNIAXIAL EXTENSION

1.IntroductionInrecenttenyears,thevoidformationandgrowthinhyperelasticmaterialhaveattractedmoreandmoreattentionandinterest.Theearliertestsfoundthatthenucleationofthemicro-voidwouldbepossibleduringthestretchingdeformationinmaterandrubbermaterials.However,t…     

退化时滞差分系统的通解

讨论具有时滞的退化差分系统，给出其初始函数的相容性条件，并给出其通解，最后举例说明之．     

能动抛光磨盘的有限元法分析

 能动磨盘在光学抛光时随磨盘移动位置和旋转角度不同而产生不同的变形以实时与大口径被抛光工件表面实现良好的吻合。模拟了能动磨盘的工作过程，探讨了用于光学抛光的可行性。以加工直径1.5m，f1/2的抛物面光学元件为例，用有限元法对能动磨盘能够产生的变形进行了仿真计算，结果表明能动磨盘能够以较高精度产生旋转对称或非对称的二次曲面。     

Triangular finite elements of HCT type and classC ρ

Let τ be some triangulation of a planar polygonal domain Ω. Given a smooth functionu, we construct piecewise polynomial functionsv∈C ^ρ(Ω) of degreen=3 ρ for ρ odd, andn=3ρ+1 for ρ even on a subtriangulation τ₃ of τ. The latter is obtained by subdividing eachT∈ρ into three triangles, andv/T is a composite triangular finite element, generalizing the classicalC ¹ cubic Hsieh-Clough-Tocher (HCT) triangular scheme. The functionv interpolates the derivatives ofu up to order ρ at the vertices of τ. Polynomial degrees obtained in this way are minimal in the family of interpolation schemes based on finite elements of this type.     

判别分析在数学建模上的应用

本文依据工科数学第十卷（１９９４年８月）数学建模ＭＣＭ—８９问题Ａ的数据，用Ｆｉｓｈｅｒ判别方法建立数学模型，进行分类，识别新样品的类别，其结论与复杂的原解法一致，此方法一般本科生就可以去作，而且没有更多的假设。     

New Families of Semi-Regular Relative Difference Sets

We give two constructions for semi-regular relative difference sets (RDSs) in groups whose order is not a prime power, where the order u of the forbidden subgroup is greater than 2. No such RDSs were previously known. We use examples from the first construction to produce semi-regular RDSs in groups whose order can contain more than two distinct prime factors. For u greater than 2 these are the first such RDSs, and for u=2 we obtain new examples.     

差分方程解对初值连续性问题

本文讨论了差分方程的解对初值的连续性问题，对较一般的方程给出了保证解对初值连续的充分条件，对线性方程（组）利用系数矩阵的特征值给出其解对初值连续的条件．     

基于平移不变壳模型的轻核(A≤6)基态特性

包含中心力、张量力、自旋-轨道力和四级自旋-轨道力且具有高斯型径向关系的唯象核子-核子相互作用被构造并通过调节有关参数来得到氘核结合能、均方根半径、D态几率、磁偶极矩和电四极矩的理论值和实验值之间的最好拟合.氘核基态波函数用对应主量子数0≤N≤1 0的平移不变壳模型基函数来展开.另外,用新的相互作用还计算了³H ,⁴He,⁵He和⁶Li核的结合能、均方根半径和磁偶极矩.这些核的波函数也是用平移不变壳模型基函数来展开,只是对前两个核,N=10;对⁵He,N=7;对⁶Li,N=6.对氘核,进一步研究了三体力的作用.所得结果与相应的实验数据符合甚好.     

An axisymmetrical quasi-Kirchhoff-type shell element for large plastic deformations

Summary An axisymmetrical shell element for large plastic strains is developed. The theory is based on the multiplicative decomposition of the material deformation gradient into an elastic and a plastic part. For quasi-Kirchhoff-type axisymmetric shells this leads to a product of the elastic and plastic stretches. By introduction of logarithmic strains the decomposition becomes additive. Plastic incompressibility is fulfilled in an exact manner.Support for this work was provided by the Deutsche Forschungsgemeinschaft (DFG) under contract Wr 19/7-1. The financial aid for the first and second author is gratefully acknowledged.