Non-coherent modelling in compositional fault tree analysis

Sharvia, Septavera; Papadopoulos, Yiannis Ioannis

Abstract

The inclusion of NOT gates in a fault tree creates a 'non-coherent' structure in which not only the failure of a component but also the negation of failure, i.e. the working state of the component, can contribute to the undesirable effects on a system. This type of non-coherent modelling remains controversial; its usefulness is still debated among academics, which explains why NOT gates have not been included in the Fault Tree Handbook. In this paper, we review work on non-coherent fault trees and highlight circumstances where non-coherent modelling is appropriate and useful. We then describe an extension to HiP-HOPS (Hierarchically Performed Hazard Origin and Propagation Studies), a recently proposed compositional safety analysis method, that enables model-based synthesis and analysis of non-coherent fault trees. A small example is given to illustrate application of the extended method and demonstrate how this type of non-coherent modelling can give a more precise and ultimately more correct insight into failure behaviour. Copyright © 2007 International Federation of Automatic Control All Rights Reserved.

Citation

Sharvia, S., & Papadopoulos, Y. I. Non-coherent modelling in compositional fault tree analysis

• Presentation Conference Type: Conference Paper (published)
• Online Publication Date: Apr 25, 2016
• Publication Date: Dec 1, 2008
• Deposit Date: Jul 13, 2021
• Journal: IFAC Proceedings Volumes (IFAC-PapersOnline)
• Print ISSN: 1474-6670
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 41
• Issue: 2
• Pages: 4138-4143
• ISBN: 9783902661005
• DOI: https://doi.org/10.3182/20080706-5-KR-1001.00696
• Public URL: https://hull-repository.worktribe.com/output/3623388