Table of Contents
Journal of Quality and Reliability Engineering
Volume 2013, Article ID 532350, 14 pages
Research Article

A Heuristic Methodology for Efficient Reduction of Large Multistate Event Trees

System Reliability and Industrial Safety Laboratory, National Centre for Scientific Research “Demokritos”, P.O. Box 60228, Agia Paraskevi, 15310 Athens, Greece

Received 31 May 2012; Revised 22 August 2012; Accepted 26 September 2012

Academic Editor: Nikolaos E. Limnios

Copyright © 2013 Eftychia C. Marcoulaki. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This work proposes a new methodology for the management of event tree information used in the quantitative risk assessment of complex systems. The size of event trees increases exponentially with the number of system components and the number of states that each component can be found in. Their reduction to a manageable set of events can facilitate risk quantification and safety optimization tasks. The proposed method launches a deductive exploitation of the event space, to generate reduced event trees for large multistate systems. The approach consists in the simultaneous treatment of large subsets of the tree, rather than focusing on the given single components of the system and getting trapped into guesses on their structural arrangement.