2-D-Truss

使用四阶Runge-Kutta算法解决两个一阶微分方程组，并输出到文件。(solve a two cupled first order differential equations)

空间数据扩边以后做fft并在频率域延拓，可用于求重磁异常(expansion of spatial data and FFT， in the frequency domain extension can be used to find the gravity and magnetic anomalies)

ADINA 系统是一个单机系统的程序，用于进行固体、结构、流体以及结构相互作用的流体流动的复杂有限元分析。借助 ADINA 系统，用户无需使用一套有限元程序进行线性动态与静态的结构分析，而用另外的程序进行非线性结构分析，再用其他基于流量的有限元程序进行流体流动分析。此外， ADINA 系统还是最主要的、用于结构相互作用的流体流动的完全耦合分析程序（多物理场）。(ADINA System is a stand-alone system program for performing complex fluid flow finite element solid structure, and fluid structure interaction analysis. With ADINA system, users do not need to use a finite element program linear static and dynamic structural analysis, but with additional nonlinear structural analysis program, and then the other program flow based on finite element analysis of fluid flow. In addition, ADINA system or main, fully coupled analysis program for fluid flow structure interaction (multi-physics).)

本程序主要根据有限元法编写，可以求解薄板的振动和静力分析问题(This procedure mainly based on the preparation of the finite element method can solve the plate vibration and static analysis of the problem)

Matlab code FDTD 2D ( dennis sullivan book )

说明：  基2基4基8以及分裂基的fft算法，代码效率很高。是难得一见的好代码。应用范围很广。(Radix-2-4-based 8 and split fft-based algorithm, a high code efficiency. Is a rare good code. Application of a very wide scope.)

非线性微分方程的人工免疫网络数学模型，适合于高水平研究者(Nonlinear differential equation mathematical model of artificial immune network, suitable for high-level researchers)

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)

计算方法《牛顿差值》(calculation method, "Newton margin")

二维粘弹性介质中波的传播的解析形式。应用Carcione等在1988年发表的《WAVE PROPAGATION SIMULATION IN A LINEAR VISCOELASTIC MEDIUM》一文中的方法，更加详细的介绍见英文描述。该代码对于做波场模拟的同学有很好的参考价值。( MATLABScript for obtaning the analytical solution for 2D wave propagation in a viscoelastic medium, based on the Appendix B of paper of Carcione et al. (1988)(1), corrected in (2). The source used is a Ricker wavelet in the y velocity component. A figure of the source temporal function and its inverse Fourier transform are provided to verify the good working of the method. Also works for elastic variables by substituting the values of vp and vs by real constant ones (vp_0 & vs_0). Attenuation is implemented by GMB-EK rheology presented in (4) and thoroughfully explained in (3). In order to make a proper comparison with numerical data it is recommended to either use the same rheology in both the numerical and the analytical. It is also possible to get an almost constant Q value by increasing a lot the number of mechanisms used in both the numerical and the analytical solutions, thus minimizing the effects of the Q fitting in the comparison.)