单相交流调压器（斩控式）

WCS-84坐标系的X，Y，Z与经纬度之间的相互转换(WCS-84 coordinate system X, Y, Z and latitude and longitude between the conversion)

ubuntu系统性能优化简单教程 关闭最小化动画 长期使用 Ubuntu 后有一种感觉，那就是在 GNOME 中启动应用程序时，速度越来越慢。在 Ubuntu 英文论坛那边看到一个技巧，可以对这个问题起到改善作用。打开 /etc/hosts 文件，可以看到类似下面的内容： 。。。。。。。。。。。。(Ubuntu system performance optimization simple tutorial Close minimize animation After long-term use of Ubuntu, it is a kind of feeling in the GNOME started in the application, the more and more slow. In English BBS there see a Ubuntu on this problem technique that can play improved. Open/etc/hosts file, can see similar the following content: )

功率谱的程序，可以完成对振动信号的功率谱分析(The power spectrum of the program, you can complete the power spectral analysis of vibration signals )

有关字符处理及获取机器日期的一些源程序- Related character processing and gain machine date some source programs

说明：  ws2811b彩灯驱动，未测试，未测试。(Ws2811b color light drive, untested, untested.)

数字电子技术电子教案-note at least eight characters, extracting passwords to note Password

一款使用纯javascript制作的简单js计算器效果(Effect of a simple JS calculator using pure JavaScript)

说明：  实现对信号的编码,将向量reshape成矩阵 ,另一个是解码(reshape vector x to matrix X, add a row and a column to X)

python 书籍 非常经典，希望大家有所收获(python very classic books, I hope you all have a harvest)

目前的代码是一个matlab函数，它提供给定信号x[n]的短时傅立叶变换（stft）。该函数是matlab命令“光谱图”的一个替代项。功能输出为： 1）一个具有复杂stft系数的矩阵，该矩阵具有跨列时间和跨行频率； 2）频率矢量； 3）时间矢量。 为了阐明函数的用法，给出了一个示例。为了方便起见，输入和输出参数在函数的开头给出。(The present code is a Matlab function that provides a Short-Time Fourier Transform (STFT) of a given signal x[n]. The function is an alternative of the Matlab command spectrogram The output of the function is 1) a matrix with the complex STFT coefficients with time across the columns and frequency across the rows; 2) a frequency vector; 3) a time vector. An example is given in order to clarify the usage of the function. For convenience, the input and output arguments are given in the beginning of the function.)