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modular techniques for dynamic fault-tree analysisIt is noted that current approaches used to assess the dependability of complex systems such as Space Station Freedom and the Air Traffic Control System are incapable of handling the size and complexity of these highly integrated designs. A novel technique for modeling such systems which is built upon current techniques in Markov theory and combinatorial analysis is described. It enables the development of a hierarchical representation of system behavior which is more flexible than either technique alone. A solution strategy which is based on an object-oriented approach to model representation and evaluation is discussed. The technique is virtually transparent to the user since the fault tree models can be built graphically and the objects defined automatically. The tree modularization procedure allows the two model types, Markov and combinatoric, to coexist and does not require that the entire fault tree be translated to a Markov chain for evaluation. This effectively reduces the size of the Markov chain required and enables solutions with less truncation, making analysis of longer mission times possible. Using the fault-tolerant parallel processor as an example, a model is built and solved for a specific mission scenario and the solution approach is illustrated in detail.
Document ID
19920073617
Document Type
Conference Paper
Authors
Patterson-Hine, F. A.
(NASA Ames Research Center Moffett Field, CA, United States)
Dugan, Joanne B.
(Duke University Durham, NC, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1992
Subject Category
QUALITY ASSURANCE AND RELIABILITY
Meeting Information
Annual Reliability and Maintainability Symposium(Las Vegas, NV)
Funding Number(s)
CONTRACT_GRANT: NAC2-478
Distribution Limits
Public
Copyright
Other