Straightforward Hermite polynomial model with application to marine structures: Fid-Bau Portal

Straightforward Hermite polynomial model with application to marine structures

Zhang, Xuan-Yi / Zhao, Yan-Gang / Lu, Zhao-Hui

Abstract To translate the marginal distributions between non-Gaussian and Gaussian processes, a Hermite polynomial model (HPM) based on the first four moments was developed and shown to have high flexibility and efficiency. Due to monotonic limitation, there are some processes that the HPM cannot be applied to. To overcome the monotonic limitation an alternative methodology has been developed, in which the need to identify the transition points between different models makes it inconvenient in practice. Furthermore, the alternative methodology applies inappropriate inverse normal transformation expressions for negatively skewed processes. Therefore, a straightforward HPM is proposed to overcome the monotonic limitation, with explicit expressions deduced and clear applicable ranges provided. The applications of the proposed model in statistical response analysis of the time-domain solution of a tension leg platform and the assessment of the reliability of a hull girder for floating, production, storage and offloading (FPSO) units are investigated via practical examples, which demonstrate that the proposed model can be efficiently applied to marine structures.

Highlights • Proposes a straightforward Hermite moment translation model. • The translation model is applicable for processes with relatively high skewness but near-Gaussian kurtosis. • The applicable range of the translation model is defined. • The translation model is efficient and accurate in marine engineering.