1t2r

说明：  计算两组向量之间的旋转矩阵。输入参数为在两个不同坐标系中的同名向量（模为1），返回参数是一个3X3的旋转矩阵。(The function of RM realize the rotation between two sets of vectors, whose magnitude are 1, defined in two different refrence frames. Input parameters are two sets of vectors r and b, return value is a rotaton matrix.)

In this section we introduce the idea of Galerkin approximations by considering a simple 1-d boundary value problem

三维PML-FDTD的C语言代码，完全匹配层的C语言实现(3D PML-FDTD in the C language code, perfectly matched layer in C language)

考虑了静态传递误差，齿轮几何偏心的影响建立3平行轴齿轮啮合动力学模型(Consider the impact of static geometry eccentric transmission error, the establishment of three parallel shaft gear gear dynamics model)

说明：  implementation of the zero -, first -, and second-order Bessel function

QR分解法是目前求一般矩阵全部特征值的最有效并广泛应用的方法，一般矩阵先经过正交相似变化成为Hessenberg矩阵，然后再应用QR方法求特征值和特征向量。它是将矩阵分解成一个正规正交矩阵Q与上三角形矩阵R，所以称为QR分解法,(QR decomposition )

UMAT for Abaqus,程序由Fortran语言写成，用于计算一般弹塑性材料的应力应变关系。(UMAT for Abaqus, written in Fortran language, is used to calculate the stress strain relationship of general elastoplastic materials.)

介绍箱梁的有限元建模 网格划分 边界条件 加载 求解的命令流(Introduction of finite element modeling of the box girder meshing load boundary conditions for solving the command stream)

说明：  Analysis of 2D structure using Mesh Free Method...

贝塞尔函数与汉克尔函数的Matlab实现(Bessel function and Hankel function of the Matlab implementation)