Conference Paper

A Mobile Based Application for Detecting Fault by Sound Analysis in Car Engines Using Triangular Window and Wavelet Transform

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Abstract

Sound energy belies an enormous amount of information which can provide assistance in various applications like navigation, communication, recognition, medical - diagnosis, detection and therapy, analysis & design of structures and many more. This paper presents a method for detecting faults in car engines just by recording their sounds through window based applications in mobile phones and processing it in the mobile phone using our algorithm. The algorithm preprocesses the sound to remove the noise if present, the noise free car engine sound is passed through a triangular window to acquire the Multi resolution coefficients for discrete wavelet transform and compare resulting plots. The Wavelet transform analysis is done and the plots are scrupulously analyzed and the faults can now be detected by referring to plots. With a little know-how non technical persons can now detect the abnormalities in car engines just be using this automation.

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... Algorithms for specific engine sound recognition were done by [1] and a mobile-based application, running in Windows, for detecting engine faults was made by [2]. Microcontroller based on-board diagnostic (OBD) system was proposed by [3] to diagnose engines which are not yet equipped with OBD. ...
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Femur Bone Distribution and Geometry Reconstruction from a Single DXA Image " accepted for SPIE Medical Imaging
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T. Whitmarsh, L. Humbert, M. De Craene et al., " Femur Bone Distribution and Geometry Reconstruction from a Single DXA Image " accepted for SPIE Medical Imaging, 2010.
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