UMAT_Hashin3D

用matlab实现的改进的布谷鸟算法——SDCS，它是将最速下降法与CS相结合的(Matlab implementation of the improved algorithm of the cuckoo- SDCS , it will steepest descent method with CS )

根据给定的等距结点上的函数值与一阶导数值, 用埃尔米特等距插值公式计算指定插值点处的函数值。(According to the given equidistant nodes function value with a first derivative values, with equidistant interpolation Hermite interpolation formula specified function value at the point.)

粘弹正演程序和模型实例,2维数值模拟正演，适应于粘弹介质，(This program can be two-dimensional numerical simulation of acoustic wave equation, Viscoelastic isotropic media.)

实现光学系统的ABCD矩阵传递的模拟，提供各种的模式衍射选着。(kelinsi xitong ABCDjuzhne)

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.)

说明：  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 Gradient) is a method between the steepest descent method and Newton's method. It only uses the first derivative information, but overcomes the disadvantage of slow convergence of steepest descent method, and avoids the disadvantage of storing and calculating Hesse matrix and solving inverse of Newton's method. Conjugate gradient method is not only one of the most useful methods to solve large-scale linear equations, but also the most effective method to solve large-scale nonlinear optimization One of the algorithms of. Among all kinds of optimization algorithms, conjugate gradient method is very important. It has the advantages of small storage, step convergence, high stability and no external parameters.)

基于前推回代法的电力系统潮流计算程序。 需要输入支路阻抗和节点功率矩阵。包括支路号、首节点号、尾节点号、支路自阻抗、尾节点给定功率。 输出各节点的电压幅值、相角和各支路电流。(Power flow calculation program based on the forward and backward substitution method. Need input the branch impedance node power matrix. Including branch number, node number, the tail node number, branch self-impedance tail node given power. The output node voltage amplitude, phase angle and current of each branch.)

计算给定序列的沃什(Walsh)变换序列。(Calculation of a given sequence of Vas (Walsh) transform sequence.)

利用matlab实现的部分CFD功能的代码，很有参考价值(Matlab to achieve part of the CFD function of the code, a very valuable reference)

：针对三容水箱是较为典型的非线性、时延对象，具有很强的代表性这一特点， 通过机理建模方法建立了三容水箱的一般数学模型。分析了线性和非线性阻力板的流量特性， 并通过实验测定了阻力板流量系数。最后给出了三容水箱的线性化模型。由仿真实验可知，非线性模型的阶跃响应和实验测得的响应曲线相吻合，(: For three-tank water tank is a more typical non-linear, time-delay object, has a strong representation of this characteristic, through the mechanism of modeling methods allow the establishment of three general mathematical model of water tanks. Analysis of linear and nonlinear flow resistance characteristics of plate, and through experimental determination of the resistance plate flow coefficient. Finally, the three-linear model of water tanks. By simulation experiments, we can see that the nonlinear model of step response and the experimentally measured response curve coincide)