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OFDM一些发展现状总结，很好的关于OFDM学习的经典文章(Some of the development of the current situation of OFDM, a very good article on the classical OFDM learning)

这个一个很完整的SNR的总结，里面包含各种有关SNR的定义和算法总结。可以供大家学习和参考(The SNR of a very comprehensive summary, which includes a variety of definitions and algorithms related to SNR summary. We can study and reference for)

说明：  K最近邻(K-Nearest Neighbor，KNN)分类算法，是一个理论上比较成熟的方法，也是最简单的机器学习算法之一。(K nearest neighbor (K-Nearest Neighbor, KNN) classification algorithm, is a more mature approach in theory is the simplest machine learning algorithms.)

利用层次分析法解决方案层对准则层和目标层的权重并相应的做出决策。(Using the analytic hierarchy process (ahp) solution on criterion layer and target layer and the corresponding weights of decision-making.)

Codes presented here are helpful in MATLAB mathematical transformations

Matlab所有函数速查手册，方便查询，比较实用(The Matlab functions Quick Reference, easy access, more practical)

非常好用的emd程序，使用时直接引用此函数即可，亲测好用(Emd very useful program, a direct reference to the use of this function, easy to use pro-test)

一个很有参考性的案例，是和自动驾驶相关的MP控制； 说明如何实时更新模型预测控制中的 预测模型的参数， 实现自适应控制。(A very useful case is MP control related to automatic driving. Explains how to update the parameters of predictive models in model predictive control in real time. Adaptive control is realized.)

说明：  算差分盒维数的matlab程序。 让窗口中的每个像素都对分数维作出贡献。首先,计算某一尺度窗口的平均灰度值 ,然后判断每一个像素的灰度 ,若大于灰度平均值 ,则累加其灰度值为 max ,若小于灰度平均值 ,则累加其灰度值为min ,用max 和min代替 在 Sarkar 和 Chaudhuri 算法中的最大值和最小值 ,再通过拟合求出分数维。 (Differential count box dimension matlab program. Let window on the fractal dimension of each pixel to contribute. First, the calculation of an average gray scale of the window, and then determine the gray scale of each pixel, if the intensity is greater than the average, the cumulative value of its gray max, if less than the average gray level, the accumulation of its gray value of min, max and min to use instead of the algorithm in Sarkar and Chaudhuri maximum and minimum, and then by fitting the calculated fractal dimension.)

机械齿轮的参数优化，设计一直齿圆柱齿轮传动, 已知其齿数比u= 4, 小轮轴 扭矩T 1= 100N. m, 单向传动, 润滑良好, 非对称布置, 两齿 轮材料 小齿轮40Cr, 调质, 齿面硬度HB= 250~ 280, [ RH ] 1 = 630MPa, [ RF ] 1= 288MPa 大齿轮45 钢, 调质, 齿面硬度 HB= 220~ 250, [ RH ] 2= 550MPa, [ RF ] 2= 204MPa, 取载荷系 数K = 1. 28。(Parameter optimization of the mechanical gear design has been Cylindrical Gear, known gear ratio u = 4, small axle torque T 1 = 100N m, one-way transmission, well-oiled, non-symmetrical arrangement of the materials of the two gears pinion 40Cr quenched and tempered tooth surface hardness HB = 250 ~~ 280 [RH] 1 = 630 MPa [RF] 1 = 288MPa large gear 45 steel, quenched and tempered tooth surface hardness HB = 220 to 250, [RH] = 550MPa , [RF] 2 = 204MPa, to take load factor K = 1 28.)