convolution3D_FFTdomain

说明：  将GNSS RINEX数据转换为电离层总电子含量(GTEX格式)(Convert GNSS RINEX data to Ionospheric Total Electron Content (GTEX format))

matlab求解变系数双曲方程，使用迎风格式(matlab solves the hypolic equation using upwind method)

面向对象的有限元程序设计 ——空间8结点等参元的分析计算(Object-oriented finite element program design- space 8 node isoparametric element analysis calculation)

说明：  上数据挖掘课的课件，是EM算法的，其中还包括最大似然值，最大似然估计，以及cluster(data mining,EM Algorithm ,Likelihood, Mixture Models and Clustering )

随机有限元理论教材，是学习随机有限元及可靠度理论的不错东东 (Stochastic finite element theory of teaching materials, are studying stochastic finite element and reliability theory is true Dongdong)

fluent中关于co2的真实气体模型的自定义程序(fluent in about co2 real gas model custom program)

用一个N点复序列的FFT同时计算两个N点实序列离散傅里叶变换(With an N-point complex sequence of N-point FFT calculate two real sequences discrete Fourier transform)

用编译的科学计算器，代码详细，清楚。设计简单。(Scientific Calculator with compiled code in detail, clearly.)

利用FFT估计正弦信号的频率,要估计一个叠加了高斯白噪声的正弦信号 的频率 ，可以通过对x(n)做傅里叶变换，得到频谱图，找出幅度的最大值对应的频率值 ，进行多次变换，求出均方误差 。改变信噪比SNR，通过仿真可以得出随着信噪比增加，均方误差减小。(Sinusoidal signal using FFT frequency estimation, to estimate a Gaussian white noise superimposed on the frequency of sinusoidal signals, can be achieved by x (n) be the Fourier transform to get spectrum to identify the magnitude of the frequency value corresponding to the maximum , several transformations, find the mean square error. Change the signal to noise ratio SNR, the simulation can be drawn as the SNR increases, the mean square error decreases.)

一个drucker prager模型的 的用户子程序，用于求解平面应变问题 abaqus UMAT and inp(drucker prager yield model for abaqus )