An algorithm for the identification of the parameters of models, based on the least-squares method and exploiting the properties of the signal wavelet packet analysis, has been proposed. A short introduction to wavelet and wavelet packets’ analysis was presented. It has been shown that the n-th step of the Walsh wavelet packet analysis can yield filtered, smooth forms of the deterministic or ra...

The method of improved wavelet transform neural network based on hybrid GA(genetic algorithm) is presented to diagnose rolling bearings faults in this paper. Genetic Artificial Neural Networks(GA-ANN) overcomes BP neural network’s fault of slow convergence, long hours of training, and falling into the local minimum point. And First, the signal is processed through the wavelet deoising, Then, th...

This paper investigates the wavelet packet based front-ends for the connected mandarin digit recognition task. Firstly an ERBlike wavelet packet basis is proposed. Then two kinds of wavelets are selected for comparison. One is the Vaidyanathan wavelet, which has good frequency selectivity but big shift variance. The other is the reverse biorthogonal spline wavelet with excellent shift invariant...

In this paper an application is presented of the wavelet packet method for denoising of impulsive vibration signals. Vibration response of machines often includes signals with periodic excitation of resonances. The aim is to extract information regarding the physical mechanism which generates the impulsive characteristics of the signals. The signals are transformed using the wavelet packet meth...

This paper introduces a new implementation of wavelet packet decomposition which is combined with SPIHT (Set Partitioning in Hierarchical Trees) compression scheme. We provide the analysis of the problems arising from the application of zerotree quantisation based algorithms (such as SPIHT) to wavelet packet transform coefficients. We established the generalized parent–child relationships for w...

We give a brief review of some of the wavelet-based techniques currently available for the analysis of arbitrary-length discrete time series. We discuss the maximal overlap discrete wavelet packet transform (MODWPT), a non-decimated version of the usual discrete wavelet packet transform, and a special case, the maximal overlap discrete wavelet transform (MODWT). Using least-asymmetric or coifle...

The automatic recognition and classification of speech under stress has applications in behavioural and mental health sciences, human to machine communication and robotics. The majority of recent studies are based on a linear model of the speech signal. In this study, the nonlinear Teager Energy Operator (TEO) analysis was used to derive the classification features. Moreover, the TEO analysis w...

Insulation used in transformer is mostly oil pressboard insulation. Insulation failure is one of the major causes of catastrophic failure of transformers. It is established that partial discharges (PD) cause insulation degradation and premature failure of insulation. Online monitoring of PDs can reduce the risk of catastrophic failure of transformers. There are different techniques of partial d...

In this paper, an object-based embedded image coding algorithm based on context classification and quadtree ordering in wavelet packet domain (OB-CCAQO) is proposed. To match up well with the quadtree-based embedded coder, a new cost function for the best basis selection is adopted in SA-DWPT (shape adaptive discrete wavelet packet transform). The significance probability of wavelet coefficient...

The 2-band discrete wavelet transform (DWT) provides an octave-band analysis in the frequency domain, but this might not be ‘optimal’ for a given signal. The discrete wavelet packet transform (DWPT) provides a dictionary of bases over which one can search for an optimal representation (without constraining the analysis to an octave-band one) for the signal at hand. However, it is well known tha...