Subjective Risk Estimation of the Rare Event

• Published in: Journal of KONES
• Main Author: Nguyen, Hoang
• Format: Article in Journal/Newspaper
• Language: English
• Published: Walter de Gruyter GmbH 2019
• Subjects: North Atlantic
• Online Access: http://dx.doi.org/10.2478/kones-2019-0013; https://content.sciendo.com/view/journals/kones/26/1/article-p103.xml; https://www.sciendo.com/pdf/10.2478/kones-2019-0013

Abstract In the safety engineering, the most frequently disadvantage in risk estimation is the lack of data. In such cases, we have to rely on subjective estimations made by persons with practical knowledge in the field of interest, i.e. experts. However, in some realistic situations, they may have uncertainty in the perceiving and evaluation of the problem considered or limited knowledge of the rare events, such as the consequences of the seagoing ship propulsion failures. The probabilistic models of the risk estimation turn out to be insufficient in modelling the subjective uncertainty. The fuzzy methods are viewed to be powerful in dealing with ambiguity and uncertainty that can be used to handle with the subjective estimation. This article addresses the intuitionistic fuzzy method in the subjective estimation of the ship propulsion failure consequences as rare event risk. In the article, a subjective model of the ship propulsion risk is developed as scenarios of the different subsequent consequences of loss of ship propulsion function until a seriously severe accident resulting in loss of seaworthiness. The model proposes an approach combining AHP method and intuitionistic fuzzy method to assess the occurrence probability and severe probability of these rare events based on the expert opinions. In order to show the applicability of the proposed model, a study case of the propulsion risk of the container carrier operating on the North Atlantic lines is conducted.