Early fault diagnosis can increase machinery availability and performance, reduce consequential damage, prolong machine life, and reduce spare parts inventories and breakdown maintenance. In this book, one intelligent fault diagnostic system is proposed based on feature extraction and selection techniques. Features are calculated from many domains: time domain, frequency domain, cepstrum domain and wavelet domain. In this way, the information of raw data is kept at best to meet different analysis methods in future. Principal component analysis and linear discriminant analysis, two feature...