BZreaction_diffusion

多相流cfd程序，用fortran实现，有多流体和dem计算功能，当然还有其它更多功能(MFiX is a general-purpose computer code developed at the National Energy Technology Laboratory (NETL) for describing the hydrodynamics, heat transfer and chemical reactions in fluid-solids systems. It has been used for describing bubbling and circulating fluidized beds and spouted beds. MFiX calculations give transient data on the three-dimensional distribution of pressure, velocity, temperature, and species mass fractions. MFiX code is based on a generally accepted set of multiphase flow equations. The code is used as a "test-stand" for testing and developing multiphase flow constitutive equations.)

很详细的一维FDTD介绍，以及MATLAB程序说明(Very detailed one-dimensional FDTD presentation and description of the MATLAB program)

高分辨率要求系统具有大的带宽，瞬时带宽的增加必将提高系统对硬件的要求，本文采用方便灵活的步进频率波形信号。脉间频率步进波形通过子脉冲载频的步进变化来获得大的有效带宽，使成像具有高分辨率，采用加窗和补零方法提高信噪比，但该信号对目标径向速度非常敏感。采用补零方法提高距离取样分辨率，使距离像细化，并用公式说明了补零只能提高距离取样分辨率，并不能改变频率步进信号的距离分辨能力。该信号波形对目标径向速度的敏感，使目标能量分散到邻近的距离单元造成距离分辨率下降，如果不事先进行速度补偿，直接对回波信号进行逆傅立叶变换，将使所成一维距离像发生频谱展宽，并伴有距离像发生平移。本文证明了当目标有径向速度时仍采用对回波信号直接进行逆傅立叶变换的方法将使一维距离像发生频谱展宽并伴有距离像发生频移，从而严重影响了一维距离像的质量。(high-resolution requirements of the system with large bandwidth, the increased instantaneous bandwidth will improve the system of hardware, In this paper, a flexible and convenient step frequency signals. Pulse frequency step-pulse waveform through the carrier frequency step to achieve great changes in the effective bandwidth. make imaging with high resolution, increasing the window and fill methods to improve signal-to-noise ratio is, However, the signal on the target radial velocity is very sensitive. Using zero-distance sampling method to improve resolution, so that distance as refinement, and formulates a zero-distance sampling can improve resolution, does not alter the frequency of the signal from stepping resolution capabilities. The signal waveform on the target radial velocity sens)

基于matlab的短时傅立叶变换，有语音读取功能！(Based on the short-time Fourier transform matlab, have voice reading!)

vc++实现的矩阵运算方面得代码，很不错的，内容绝对好吃(matrix operations, code vc++ achieve very good, the content is absolutely delicious)

利用Abaqus子程序UAMP实现PID控制。(PID control is implemented using the Abaqus subroutine UAMP.)

高斯-赛德尔迭代法是解线性方程组的常规算法，本文是C语言的高斯-赛德尔计算代码(Gauss-Seidel C program)

共轭梯度法（Conjugate Gradient）是介于最速下降法与牛顿法之间的一个方法，它仅需利用一阶导数信息，但克服了最速下降法收敛慢的缺点，又避免了牛顿法需要存储和计算Hesse矩阵并求逆的缺点，共轭梯度法不仅是解决大型线性方程组最有用的方法之一，也是解大型非线性最优化最有效的算法之一。 在各种优化算法中，共轭梯度法是非常重要的一种。其优点是所需存储量小，具有步收敛性，稳定性高，而且不需要任何外来参数。(Conjugate gradient method (Conjugate Gradient) is between the steepest descent method between the method and Newton' s method, it takes only a first derivative information, but to overcome the steepest descent method convergence slow shortcomings, but also to avoid the Newton method needs to be stored Hesse and disadvantages of computing inverse matrix and the conjugate gradient method is not only one of the most useful methods to solve large linear equations, solution of large-scale nonlinear optimization is one of the most effective algorithm. In various optimization algorithm, conjugate gradient method is a very important one. The advantage is that a small amount of memory required, with step convergence, high stability, and does not require any external parameters.)

可进行最小二乘法线性拟合输出，包含源代码及生成后的程序(Least-squares linear fit can be output)

Vortex flow around a square cylinder function method of numerical simulation