Prof. Liyang XieSchool of Mechanical Engineering,
Northeastern University, China
Speech Title: On Probability Distribution of Material Strength and Robust Parameter Estimation
Abstract: Material strength is a random variable with a threshold much greater than zero. Therefore, the commonly used normal distribution, log-normal distribution and two-parameter Weibull distribution are not appropriate. This paper uses the three-parameter Weibull distribution to describe material strength, presents a simple parameter estimation method according to small size samples. The method is based on the error performance that the differences between the scale parameter values calculated with the different sample values based on erroneous location parameter values and shape parameter values are the parameter values dependent. By minimizing the differences, the right location parameter and parameter are identified, and the scale parameter is obtained. To guarantee the robustness of the parameter estimation result, a robust minimum value critical is applied. Simulated parameter estimation results show that this method is better than the conventional maximum likelihood method and least squares method.
Keywords: Material strength, Three-parameter Weibull distribution, Parameter estimation, Small size of sample.
Biography: Prof. Liyang Xie is a professor of Mechanical Engineering at Northeastern University, Shenyang, China. He received his BS (1982) in mechanical Manufacturing, MS (1985) & PhD (1988) in structural integrity from Northeastern University, Shenyang, China. He worked one year (1996) in the Probabilistic Safety Analysis Institute, TUVE Nord, Hamburg, Germany and two more years in the Department of Plant Safety, Otto-von-Guericke University, Magdeburg, Germany during 1997-1998. His research interests include structural integrity, reliability and system probabilistic risk analysis. He has published more than 100 research papers in peer reviewed journals and six books. He is editorial board member of Int. J. of Reliability and Safety, Int. J. of Advances in Reliability and Engineering Failure Analysis. He is Vice Chairman of Fatigue Branch of Chinese Materials Research Society, Vice Chairman of Reliability branch of Chinese society of Mechanical Engineering.