The definition and measurement of the probability density function in lamb wave damage detection based on data fusion

Abstract

The type and parameters of the probability density function (PDF) of damage occurrence were discussed. Based on the new definition of the PDF of the presence of damage given in this paper, the parameters of PDF, such as its expectation and variance, were obtained by hypothesis testing of mathematical statistics theory, which refers to the process of choosing between competing hypotheses about a probability distribution based on observed data from the distribution. In the present measurement method based on mathematical statistics theory, both the type and characteristics of the PDF can be determined according to scientific analysis of the experiment data. A numerical simulation was carried out to demonstrate this hypothesis testing-based measurement method. Compared with the existing empirical formula method, the present method can be more reliable in application. And with the present method, the Lamb waves damage detection method based on data fusion will be theoretically completed.