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matlab 二维圆柱绕流，使用波尔茨曼方法进行数值模拟(cylinder，about cylinder in lattice boltzmamn method)

说明：  MIT Matlab教程：INTRODUCTION TO MATLAB — Fall 1999 Thomas F. Weiss Last modification September 9, 1999 1(MATLAB is a programming language and data visualization software package which is especially effective in signal processing and systems analysis. This document is a brief introduction to MATLAB that focuses on those features that are of particular importance in 6.003.1 It is assumed that the reader is familiar with Project Athena, has an Athena account, and has little or no experience with MATLAB. Other MATLAB help is available through Athena consulting which offers a number of more tutorial handouts and short courses (ext. 3-4435), on-line consulting (type olc at the Athena prompt), and Athena on-line help (type help at the Athena prompt). There are a number of books available that describe MATLAB. For example, Engineering Problem Solving with Matlab, by D. M. Etter, published by Prentice-Hall (1997) and Mastering MATLAB, by Hanselman and Littlefield, published by Prentice-Hall (1996). The paperback MATLAB Primer by K. Sigmon, published by CRC Press (1994) is a handy summar)

该程序属于地震信号处理方面，用于估计零偏移距VSP数据中的Q值。(The program is part of the seismic signal processing for estimating the zero-offset VSP data in the Q value.)

说明：  基于压缩感知的的图像去噪，用于不同维数，(image denoising based on cs)

Region growing algorithm for gray-scale images (1-channel). Implemented on MATLAB for segmentation.

i need FDTD code using MATLAB

利用matlab编程实现粒子群算法，来进行寻找最优解(particle swarm optimization)

用matlab实现了zigzag算法，实现功能：对任意维数的图片都都能进行加密和解密(Using matlab to achieve a zigzag algorithm functions: For any dimension pictures are able to encrypt and decrypt)

1、验证窗函数 N 变化时，验证其频谱主瓣副瓣比、主瓣宽度的变化。 a)矩形窗函数的 N 变化时，验证其其频谱主瓣副瓣幅度比基本不会发生变化， 而主瓣宽度将会变窄。这说明，当用矩形窗函数设计滤波器时，增大 N 不能使 得阻带衰减减小，但能够减小过渡带。 b)再选取其他的窗如 hamming/hanning 窗，验证当 N 变化时，其频谱主瓣宽 度变化、主瓣副瓣比值变化情况。 2、用窗函数法设计线性相位 FIR 低通，通带截止频率 wp=0.5PI, 阻带截止频率 ws=0.6PI, 阻带衰减不小于 40dB,通带衰减不大于 3dB. a)选取 Hanning,Hamming 窗查看设计出来的 FIR 的过渡带宽和阻带衰减是否 满足要求，二者有什么不同。 b)使用 hamming 窗，将窗长增大 1 倍，设计 FIR。验证同样的窗函数类型 (hamming)，不同窗长度时，设计出来的 FIR 的过渡带宽和阻带衰减都有什么变 化。 3、不使用 Matlab 系统函数得到上一项指标的低通，并与上一项结果比较。 4 用窗函数法设计线性相位 FIR 高通，通带截止频率 wp=0.8PI, 阻带截止频率 ws=0.7PI, 阻带衰减不小于 30dB,通带衰减不大于 3dB.(An actual filter is implemented using the truncated unit impulse response sequence of the ideal filter. For the ideal low pass filter, the unit impulse response h, N, D () is intercepted by a length of N, and the length is The N sequence H (n), when intercepted, guarantees causality and linear phase requirements for the filter. In order to reduce the Gibbs effect, the H (n) window is added, and the appropriate window function is selected to ensure the stopband attenuation and Transition zone requirement. Note that the sidelobe of the window function affects the stopband attenuation of the filter, and the main lobe width affects the filter Transition bandwidth.)

ESPRIT的谱估计算法，含有自动定阶，设置相应参数即可直接运行。(ESPRIT algorithm for spectral estimation, with automatic set-order, set the corresponding parameters can be directly run.)