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An Efficient Approach for the Reliability Analysis of Phased-Mission Systems with Dependent FailuresWe consider the reliability analysis of phased-mission systems with common-cause failures in this paper. Phased-mission systems (PMS) are systems supporting missions characterized by multiple, consecutive, and nonoverlapping phases of operation. System components may be subject to different stresses as well as different reliability requirements throughout the course of the mission. As a result, component behavior and relationships may need to be modeled differently from phase to phase when performing a system-level reliability analysis. This consideration poses unique challenges to existing analysis methods. The challenges increase when common-cause failures (CCF) are incorporated in the model. CCF are multiple dependent component failures within a system that are a direct result of a shared root cause, such as sabotage, flood, earthquake, power outage, or human errors. It has been shown by many reliability studies that CCF tend to increase a system's joint failure probabilities and thus contribute significantly to the overall unreliability of systems subject to CCF.We propose a separable phase-modular approach to the reliability analysis of phased-mission systems with dependent common-cause failures as one way to meet the above challenges in an efficient and elegant manner. Our methodology is twofold: first, we separate the effects of CCF from the PMS analysis using the total probability theorem and the common-cause event space developed based on the elementary common-causes; next, we apply an efficient phase-modular approach to analyze the reliability of the PMS. The phase-modular approach employs both combinatorial binary decision diagram and Markov-chain solution methods as appropriate. We provide an example of a reliability analysis of a PMS with both static and dynamic phases as well as CCF as an illustration of our proposed approach. The example is based on information extracted from a Mars orbiter project. The reliability model for this orbiter considers the various phases of Launch, Cruise, Mars Orbit Insertion, and Orbit. Some of the CCF for the orbiter in this mission include environmental effects, such as micrometeoroids, human operator errors, and software errors.
Document ID
20090026417
Acquisition Source
Jet Propulsion Laboratory
Document Type
Conference Paper
External Source(s)
Authors
Xing, Liudong
(Massachusetts Univ. North Dartmouth, MA, United States)
Meshkat, Leila
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Donahue, Susan K.
(Virginia Union Univ. VA, United States)
Date Acquired
August 24, 2013
Publication Date
May 1, 2006
Subject Category
Statistics And Probability
Meeting Information
Meeting: 8th International Conference on Probabilistic Safety Assessment and Management
Location: New Orleans, LA
Country: United States
Start Date: May 14, 2006
End Date: May 19, 2006
Distribution Limits
Public
Copyright
Other
Keywords
reliability analysis
common cause
phased mission systems

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