“…With the rapid development of electronic technology, many methods such as the neural network [1,11,14], the wavelet [2,15], the optimal stimulus signal selection [26,32], the support vector machine [7,12], the Mahalanobis distance model [21], the fuzzy method [6,28], the hidden Markov model (HMM) [33], the test point selection [3,24] and the coefficient-based test method [13] are studied in depth. In these methods, linear models are used.…”