Programmer Think

1, Introduction In 1974, the French engineer J.Morlet first proposed the concept of wavelet transform. In 1986, the famous mathematician Y.Meyer accidentally constructed a real wavelet base and established the multi-scale analysis of constructing wavelet base in cooperation with S.Mallat. Wavelet analysis began to flourish. Wavelet analysis ha ...

1, Introduction 1 Overview BP (Back Propagation) neural network was proposed by the scientific research group headed by Rumelhart and McCelland in 1986. See their paper learning representations by Back Propagation errors published in Nature. BP neural network is a multilayer feedforward network trained by error back propagation algorithm. It ...

1, Introduction 1 grayscale The process of converting color image into gray image is called image graying. The pixel value in the color image is determined by the three RGB components, and each component has 0-255 (256) choices. In this way, the pixel value of a pixel can have 16 million possibilities (256256256), while the pixel value of the ...

1, Overview of wavelet threshold denoising The noise of power quality disturbance signal mostly exists in the form of Gaussian white noise. Wavelet transform is used for multi-resolution decomposition of the signal. Because wavelet transform has the characteristics of removing data correlation, it can separate the energy of useful signal and n ...

1, Introduction to speech processing (with course assignment report) 1 Characteristics of voice signal Through the observation and analysis of a large number of voice signals, it is found that voice signals mainly have the following two characteristics: ① In the frequency domain, the spectral components of speech signals are mainly concentrate ...

1, Introduction 1 origin and development of ant colony algorithm (ACA) In the process of studying the new algorithm, Marco Dorigo and others found that when ant colony is looking for food, they can exchange foraging information by secreting a biological hormone called pheromone, so they can quickly find the target. Therefore, in their doctoral ...

Using MATLAB to draw a better vector diagram The basic data unit of MATLAB is matrix. Using MATLAB, it is convenient to draw vector distribution map, such as the sampling data of air flow; Gradient of function; The normal vector of the surface, and so on. Matlab's built-in quiver and quiver3 functions can meet this demand, but the arrow ty ...

1, Case description Three classic images (lena, pepper and barbara) are added with Gaussian noise, multiplicative noise and salt and pepper noise respectively. Gaussian white noise: the mean value is 0 and the variance is 0.05. Salt and pepper noise: noise density 0.10. Multiplicative noise: here is the noise with uniformly distributed mean va ...

1, Mathematical representation of fault information In the figure above, K represents the circuit breaker, and each circuit breaker has an FTU device, which can feed back whether the circuit breaker switch is overcurrent. It is used to represent the uploaded fault information, which reflects whether the fault current flows at each section swit ...

Please note before reading: 1. This learning note is the learning record of MATLAB training of HelloWorld programming Association of central China Normal University in 2021 winter vacation. It is a summary and expanded reading based on the training classroom content. The content of the blog is written and edited by @ K2SO4 potassium and publis ...