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这是几篇关于粒计算在故障诊断中的应用，对学习粒计算的应用很有帮助。(This is a few on Granular Computing in Fault Diagnosis of learning the application of granular computing helpful.)

分享一个外国人编写的FDTD程序,可以用来计算微带线和微带贴片天线,程序中采用的是均匀网格划分,但也可以在容易地在它基础上改写成非均匀网格.其边界条件与Sheen的程序不同,这里采用二阶技术.(Prepared to share a foreigner FDTD procedures, can be used to calculate the microstrip lines and microstrip patch antenna, the procedure used is uniform mesh, but can also easily rewrite it into the basis of non-uniform grid. its boundary conditions with different processes and Sheen, where second-order technology.)

矩阵计算，包括加减乘，反矩阵，python源码，可以直接使用(matrix calculation)

最优潮流计算程序（使用电力系统专业，属于非线性规划问题）．(optimal power flow calculation procedure (using power systems professional, is Nonlinear Programming).)

数学最优问题中，拉格朗日乘数法（以数学家约瑟夫·路易斯·拉格朗日命名）是一种寻找变量受一个或多个条件所限制的多元函数的极值的方法。(In the mathematical optimization problem, the Lagrange multiplier method (named by the mathematician Joseph Luis Lagrange) is a method of finding the extremum of a multivariate function which is restricted by one or more conditions.)

利用Python实现特征的MinMax标准化和Z-Score标准化两种特征归一化方法。并用原特征、两种归一化特征分别进行朴素贝叶斯模型训练，比较模型性能。(Two normalization methods of MinMax normalization and Z-Score standardization are implemented by Python. The naive Bayes model is trained with the original features and two normalization features respectively to compare the performance of the model.)

说明：  fractal compression using wavelet

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.)

首先根据高斯白噪声频率充满整个频带的特性，通过双树复小波包变换对高斯白噪声进行分解，利用频带能量泄漏的定量分析方法，验证了双树复小波包变换具有较低的频带能量泄漏特性；其次利用双树复小波包变换逐层分解信号，对每层分解所得分量求其FFT谱的峭度，得到基于双树复小波包变换的谱峭度图，根据图中峭度最大的原则，可以自动准确的选择信号分解最佳层数和最佳分量；最后将基于双树复小波包变换的谱峭度图的故障诊断方法应用于实际工程中，对齿轮故障振动信号进行分析，选择最佳分解层数和分量后利用希尔伯特包络解调，有效准确地提取了故障特征信息，验证了方法的可行性和有效性(The parameters of a filter were determined by experience, and that has a great influence on the results of signal processing. The discrete wavelet packet transform has a larger energy leakage of frequency band, which obviously affected the results of the envelope demodulation. It is necessary to have a method with a lower energy leakage of the frequency band before envelope demodulation. The dual tree complex wavelet packet transform (DT-CWPT) was a new signal processing method that had many good qualities. Because the energy leakage of the frequency band was smaller when the signal was decomposed by a dual tree complex wavelet packet transform, the dual tree complex wavelet packet transform was used to extract the fault feature information in the field of fault diagnosis. In this paper, first, according to the characteristics of Gaussian white noise, whose frequency was full of the whole frequency band, Gaussian white noise was decomposed by a dual-tree complex wavel)

是ABAQUS有限元模拟软件的子程序，主要研究损伤断裂(a subroutine of ABAQUS for damage and fracture )