BEM-acoustic-problems

说明：  虽然现在网上的FFT程序很多，但是有的结果是错误的，比如说，经过一次正反变换后，不能得到原来的数列，所以，本人测试了多个程序，提供几个能用的，给大家，希望大家支持！ (Although many online FFT program, but some results are wrong, for example, through a positive and negative change, you can not get the original series, so I tested several programs to provide a few usable for everyone I hope we can support!)

序列二次规划(SQP)方法被认为是解决非线性约束优化最有效的方法之一，传统的SQP算法每一步迭代都要求解QP子问题。 　　(Sequential two times programming (SQP) is considered to be one of the most effective ways to solve nonlinear constrained optimization. The traditional SQP algorithm requires QP iteration for every iteration.)

模型大小延伸程序；及实现快速傅里叶变换的小程序。该两程序通俗易懂，适合初学者(Model extension、 FFT)

《计算理论导引》(作者)[美] Michael Sipser(译者)张立昂 王捍贫 黄雄 机械工业2000年2月第1版.pdf(Computational Theory，(Author) [America] Michael Sipser (translator) Zhang Li Ang Wang Hanpin Wong Hung Machinery Industry in February 2000 1st edition. Pdf)

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.)

用Python语言写的多目标进化算法库（2017年最新版本），包含常见的多目标进化算法以及当前最新文献中的最新算法，能够实现不同算法之间的性能比较（包含常见的GD, IGD, HV等评价指标自动生成）。可以供进化计算、多目标优化、单目标优化算法的学习参考。Python语言版本简单易懂，实用性强。(Library of multi-objective evolutionary algorithm written in Python language (the latest version in 2017), including multi-objective evolutionary algorithm and the most common new literature in the new algorithm, can realize the performance between different methods (including the common GD, IGD, HV and other evaluation index generation). It can be used as a reference for evolutionary computation, multi-objective optimization and single objective optimization. Python language version is simple and easy to understand, practical.)

弹性补偿法的程序，在abaqus中进行二次开发，可以计算各种结构的极限载荷。(The elastic compensation method of the procedure, carries on two times of developments in ABAQUS, can be used to calculate the limit load of various structures. )

c++的有限元源码,带说明书和测试数据,是难得的有限元开发资料.(This is the code of finite element method, with manual document and data samples, it is valusble for FEM development)

C + +程序，根据用户的输入可以产生特定的Gauss -1型切比雪夫正交规则，(C++ program which can generate a specific Gauss-Chebyshev type 1 quadrature rule, based on user input)

加权总体最小二乘matlab工具箱，包含各种总体最小二乘算法的源代码(weighted total least squares toolbox)