Caracterização matemática do ruído acústico em ambiente fabril.

Abstract

The industrial environment provides many risks to workers and the audible noise is one of them . Chronic exposure to audible noise may cause hearing damage physiological and worker’s body. On this dissertation is presented a methodology to analyze existing levels of sound pressure and the behavior of audible noise in an industrial environment . A shoe industry in the city of Campina Grande - PB was the chosen as field of research to test the methodology . This analysis results in the mathematical characterization of the audible noise. Three mathematical entities are calculated with the data obtained in the field : the power spectral density , probability density function , the autocorrelation of the measured acoustic noise . Of these, only the first two are described in an approximate manner by means of mathematical models . For the case of the probability density function , this mathematical characterization addresses from another point of view the classical problem in the area of ??communications , the determination of the probability density function of the sum of sinusoidal signals with a Gaussian noise , using for this purpose , Chebyshev polynomials of the first order . Estimation of power distribution components in the frequency coupled mathematical model to describe the behavior of this random noise allows the development of techniques for active noise control in industrial environments . Thus , results of this thesis the development of a scientific method that simply meets the applicable regulations in the country , and it adds important information about the object of measurement for a general and accurate solution of the problem addressed .