RA0-estimation

这本电子书是Stephen J. Chapman著，邢树军译，内容简单，讲解详细，并且附有常见的编程错误和好的编程习惯，比较适合初学者。(This eBook is Stephen J. Chapman a, Xing Shujun translation, is simple to explain in detail, and with a common programming errors and good programming habits are more suitable for beginners.)

Twenty Four pulse converter is VSI converter used to convert the DC voltage to AC voltage using Sin Pulse Width Modulation technique.

用于地球物理中重力和磁力位场边界提取的几个常用的算法，包含数据处理，建模，和滤波。(Gravity and Magnetic Data Mapping, Processing, Modeling and Filtering Software.)

检测电机转速通过pid算法对电机PWM占空比调节使电机达到预定转速(The motor speed is detected, and the duty cycle of the motor PWM is adjusted by the PID algorithm, so that the motor reaches the desired speed)

1 SIFT 发展历程 SIFT算法由D.G.Lowe 1999年提出，2004年完善总结。后来Y.Ke将其描述子部分用PCA代替直方图的方式，对其进行改进。 2 SIFT 主要思想 SIFT算法是一种提取局部特征的算法，在尺度空间寻找极值点，提取位置，尺度，旋转不变量。 3 SIFT算法的主要特点： a) SIFT特征是图像的局部特征，其对旋转、尺度缩放、亮度变化保持不变性，对视角变化、仿射变换、噪声也保持一定程度的稳定性。 b) 独特性(Distinctiveness)好，信息量丰富，适用于在海量特征数据库中进行快速、准确的匹配[23]。 c) 多量性，即使少数的几个物体也可以产生大量SIFT特征向量。 d) 高速性，经优化的SIFT匹配算法甚至可以达到实时的要求。 e) 可扩展性，可以很方便的与其他形式的特征向量进行联合。 4 SIFT算法步骤： 1） 检测尺度空间极值点 2） 精确定位极值点 3） 为每个关键点指定方向参数 4） 关键点描述子的生成 本包内容为sift算法matlab源码(1 SIFT course of development SIFT algorithm by DGLowe in 1999, the perfect summary of 2004. Later Y.Ke its description of the sub-part of the histogram with PCA instead of its improvement. 2 the SIFT main idea The SIFT algorithm is an algorithm to extract local features in scale space to find the extreme point of the extraction location, scale, rotation invariant. 3 the main features of the SIFT algorithm: a) SIFT feature is the local characteristics of the image, zoom, rotate, scale, brightness change to maintain invariance, the perspective changes, affine transformation, the noise also maintain a certain degree of stability. b) unique (Distinctiveness), informative, and mass characteristics database for fast, accurate matching [23]. c) large amounts, even if a handful of objects can also produce a large number of SIFT feature vectors. d) high-speed and optimized SIFT matching algorithm can even achieve real-time requirements. e) The scalability can be very convenient fe)

Finally it is observed that by using this filter, the common mode noise level of 2MHz resonant converter is suppressed according to CISPR 22 standard limits

图像投影函数，对图像从各个方向完成投影 以两种不同形式的投影出现！(An image projection function to complete the projection of images from various directions to the projection of the two different forms appear!)

用函数输出不同占空比信号的波形和功率谱密度，一段简单的matlab程序(Function output duty cycle signal with different waveforms and power spectral density, a simple piece of matlab program)

电动工具控制源程序 投入量产运用，吐血共享(motor controler)

display the Disclaimer in MATLAB environment