exam4

说明：  主要用于计算最常见的二维材料石墨烯纳米带的能带结构(It is mainly used to calculate the energy band structure of graphene nanoribbons, the most common two-dimensional material.)

用于计算传热学五种常见对流扩散数值计算对比(Numerical comparison of five kinds of convection diffusion)

根据高斯光束的特性，在matlab中作出束腰半径为0.5mm的高斯光束在束腰处的三维光强分布图。(According to the characteristics of the Gauss beam, the three-dimensional intensity distribution of the Gauss beam with the waist radius of 0.5mm at the waist is made in MATLAB.)

说明：  5种不同PML的效果对比，基于MATLAB进行分析，通过修改可以改为自己的PML代码(Effect comparison of five different PML)

SIMPLE算法程序，peric教材的程序(SIMPLE algorithm code)

实现快速分数阶傅里叶变换功能。分数阶傅里叶变换是整数傅里叶变换的普遍形式，可用于光的菲涅尔衍射模拟。(The function of fast fractional Fourier transform is realized. Fractional Fourier transform is a general form of integer Fourier transform, which can be used to simulate Fresnel diffraction of light.)

说明：  一个基于有限元方法的平面问题求解器，支持网格类型为二维四边形四节点单元和四边形八节点单元的有限元网格： 前处理——用Abaqus建模编号并导出数据 在Matlab中读取数据文件 计算单元刚度矩阵（采用高斯积分），组集结构刚度矩阵 组集结点载荷向量，引入位移边条 求解结点位移，单元应力应变 后处理——绘制应力应变位移云图，与Abaqus结果对照(A plane problem solver based on finite element method)

说明：  通过拉格朗日方程模拟仿真双摆系统的运动过程，并生成poincare映射图(The motion process of double pendulum system is simulated by Lagrange equation, and Poincare map is generated.)

平面波从石英玻璃入射到空气中的P、S分量的反射波相位和透射波相位随入射角度的变化(The phase of the reflected wave and the phase of the transmitted wave of the plane wave from the quartz glass to the air in P and S vary with the angle of incidence.)

说明：  重磁异常正演方法，是在给定地质体的形状大小、空间位置及物性参数的条件下，求它外部空间任意点上的物理场值。(The forward method of gravity and magnetic anomaly is to calculate the physical field value at any point in the outer space of a given geological body under the condition of its shape, size, space position and physical parameters.)