Failure mode and effects analysis based on rough cloud model and MULTIMOORA method: Application to single-point mooring system

Abstract

The failure mode and effects analysis (FMEA) is an important tool for risk assessment, which can identify and eliminate potential failure modes in a system. However, due to the inherent drawbacks of the traditional FMEA method, the risk assessment results may be inaccurate. In this study, an FMEA approach based on the rough cloud model and MULTIMOORA (Multi-Objective Optimization on the basis of Ratio Analysis plus full multiplicative form) method is developed to evaluate the risk of the single-point mooring system. The main contributions of this study are as follows. First, an interval asymmetric rough cloud (IARC) model is proposed by combining cloud model and rough set theory, which can deal with the randomness of expert individual evaluation and the uncertainty of expert group evaluation. Second, an IARC power weighted average operator is proposed to eliminate the influence of extreme expert opinions when aggregating expert opinions. Third, according to the feature of single-point mooring system failure, a two-level risk factor hierarchical structure is established, and the subjective and objective weights are integrated to determine the risk factor weights. Fourth, an extended MULTIMOORA method based on the rough cloud model is developed to determine the risk priority of failure modes. To illustrate the implementation process of the approach, we have applied it to a single-point mooring system of an FPSO (Floating Production Storage and Offloading) in the South China Sea. The comparison analysis with the existing methods is also presented to validate the feasibility and effectiveness of this approach.