关于几种复杂函数序列的线性无关性的讨论

讨论了在晶体生长问题中遇到的几种复杂函数序列的线性无关性,并得出了有关函数线性无关性的几个结论．     

数学物理方程的MATLAB数值解法与可视化

选取数学物理方程及其初、边值问题的差分格式,使用有限差分法,利用M atlab得出其图形解;直接利用M at-lab的PDE工具箱,借助图形用户界面得到数学物理方程的图形解;对结果进行了分析总结.     

小波阈值方法在Laplace方程中的应用

把Laplace方程的柯西问题化为算子方程来考虑,右端项是非精确数据。运用小波对偶最小二乘法,得到了阶最佳的收敛性稳定性分析和非线性自适应。     

Different influence of contextual educational factors on boys＇ and girls＇ reading achievement

The results of lEA （The International Association for the Evaluation of Educational Achievement） PIRLS 2006 （Progress in International Reading Literacy Study） has showed that Latvia has the 6th largest gender gap in reading literacy scores and that is an indication of a serious problem of education in this country. The purpose of the paper is to find out reasons behind boys＇ low achievement to help improve their reading literacy. The proposed hypothesis is that boys and girls are differently affected by the same factors. If that is so, teachers, parents and other education practitioners should be aware of this fact to adapt reading literacy studies for both genders at maximum efficiency. In this research, PILRS 2006 data are used and different structural equation models are created to find out which factors have the most influence on boys＇ reading achievement. Structural equation modeling （SEM） is based on achievement scores and student and parent questionnaire data. The model formed using all population data was applied to boys＇ and girls＇ data separately to observe different influence of the same factors on students reading achievement scores. The comparison of standardized coefficients of structural equation model among five countries （Spain, Russian Federation, Lithuania, Latvia and Trinidad and Tobago） has been performed. Running the same model over different boys＇ and girls＇ data of different countries has showed that the strengths of relationships among the variables are similar. It was expected to observe noticeable differences between SEM coefficients of boys＇ and girls＇ data, but it turned out that big gender differences in reading achievement does not mean big differences in standardized coefficients of structural equation model and vice versa. It is found that school environment has greater impact on boys reading literacy.     

一类广义RLW方程的初值问题

考虑一类广义RLW方程u1-uxxt＋p（u）x=f（uz）z＋g（u）＋γuzz在f、g、p及初值u0满足一定条件下,用压缩映射原理得到了上述问题局部广义解的存在唯一性．     

非齐次线性方程组通解的一种简便求法

给出一种只需用矩阵的初等行变换求非齐次线性方程组的通解的一种简便方法。     

逆矩阵的判定方法

判定矩阵是否可逆对矩阵的运算起着至关重要的作用。判定逆矩阵可用定义法、行列式法、初等变换法、初等矩务法、对角矩阵法、行列式性质法、线性方程组法、向量组的秩法等.     

求解非线性方程组的改进牛顿法

对传统牛顿法进行了改进,提出了求解非线性方程组的改进牛顿法。在一定的假设条件下,证明了该算法的全局收敛性和超线性收敛。     

图书馆网站Web页面增长规律研究——基于美国三种类型图书馆网站的典型调查分析

以美国公共、专业和高校三种类型图书馆网站的代表为典型调查对象,利用Alltheweb搜索引擎检索它们每年新出现的网页数量及建立网页数据的时间序列.然后运用统计学中的时间序列分析方法和SPSS软件对数据进行统计分析.得出结论:在图书馆网站的初始发展阶段,网页增长经历三个时期、符合普赖斯科学文献指数定律、增长指数与平均发展速度正相关.图1.表3.参考文献8.     

一类mKdV方程的孤波解

对双曲函数法进行扩展,然后利用一种基于符号计算的代数方法,结合Maple环境中的Epsilon软件包,求解mKdV方程,获得了若干其它方法不曾给出的形式更为丰富的新的显式行波解,其中包括孤波解、三角函数解、双曲函数解和Weierstrass椭圆函数周期解．并用扩展了的双曲函数法求得mKdV方程的新周期波解和孤波解．