Neural network based wheel bearing fault detection and diagnosis using wavelets /

In this dissertation, we introduce neural network based algorithms to classify signals with the conjunction of Wavelet Transform and Genetic Algorithm techniques. Specifically, we use these algorithms on wheel bearing fault detection and diagnosis systems. Wavelet Transforms have been widely used fo...

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Bibliographic Details
Main Author: Xu, Peng, 1974-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 2002.
Subjects:
Online Access:http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=765106071&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD
Description
Summary:In this dissertation, we introduce neural network based algorithms to classify signals with the conjunction of Wavelet Transform and Genetic Algorithm techniques. Specifically, we use these algorithms on wheel bearing fault detection and diagnosis systems. Wavelet Transforms have been widely used for pattern recognition applications. Features extracted from scales (sub-bands) produced by Wavelet Transforms are highly correlated due to the redundancy of the scale (sub-bands). These correlated features may cause the classifiers to converge very slowly and reduce the classification performance. Feature dimension reduction techniques are essential to making wavelets more powerful. In this dissertation reduction techniques are essential to making wavelets more powerful. In this dissertation, we introduce Genetic Algorithm to reduce the feature dimension in two steps: 1) selecting the subset of sub-bands, and 2) selecting features belonging to these sub-bands. We use both multiplayer perceptron (MLP) and support vector machine (SVM) as classifiers. The original SVMs are developed for two-class problem. To extend the SVMs to our applications, we develop a multi-SVM that is optimized by adjusting the cost-factor of each individual SVM. In addition, we provide some advanced topics that will be helpful for the future research of railroad wheel bearing condition monitoring applications.
Item Description:Vita.
"Major Subject: Electrical Engineering".
Physical Description:xii, 124 leaves : illustrations ; 28 cm.
Issued also on microfiche from University Microfilm Inc.
Bibliography:Includes bibliographical references (leaves 115-123).