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Spiridon CREŢU

Department of Machine Design, Technical University of Iaşi, ROMANIA


Abstract. The paper presents an algorithm for computer simulation of non-Gaussian surfaces. By using a random number generator, a input matrix is formed as a first representation of a Gaussian roughness with zero mean, and unit standard deviation. The autocorrelation function was assumed to have an exponential form. To fulfill this requirement, in the first step, the matrix containing the roughness heights was obtained by a linear transformation of the input matrix. In the second step the skewness and kurtosis of the input sequence have been established for the desired skewness and kurtosis of an output sequence. Finally the non-Gaussian random series have been generated by using the Johnson translator system.
The numerical results pointed out that the developed algorithm can be further used to simulate manufacturing processes that produce real surfaces which may present a non-Gaussian distribution, as well as the abrasive wear and running in phenomena.


Keywords: roughness, autocorrelation, skewness, kurtosis




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