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A general formula for the downtime distribution of a parallel system

Published online by Cambridge University Press:  14 July 2016

Harald Haukås*
Affiliation:
Rogaland University Centre and University of Oslo
Terje Aven*
Affiliation:
Rogaland University Centre and University of Oslo
*
Postal address for both authors: Rogaland University Centre, Ullandhaug, 4004 Stavanger, Norway.
Postal address for both authors: Rogaland University Centre, Ullandhaug, 4004 Stavanger, Norway.

Abstract

In this paper we study the problem of computing the downtime distribution of a parallel system comprising stochastically identical components. It is assumed that the components are independent, with an exponential life-time distribution and an arbitrary repair time distribution. An exact formula is established for the distribution of the system downtime given a specific type of system failure scenario. It is shown by performing a Monte Carlo simulation that the portion of the system failures that occur as described by this scenario is close to one when we consider a system with quite available components, the most common situation in practice. Thus we can use the established formula as an approximation of the downtime distribution given system failure. The formula is compared with standard Markov expressions. Some possible extensions of the formula are presented.

Type
Research Papers
Copyright
Copyright © Applied Probability Trust 1996 

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References

[1] Aven, T. (1993) On performance measures for multistate monotone systems. Reliability Eng. Syst. Safety 41, 259266.CrossRefGoogle Scholar
[2] Aven, T. (1992) Reliability and Risk Analysis. Elsevier, London.Google Scholar
[3] Barlow, R. E. and Proschan, F. (1975) Statistical Theory of Reliability and Life Testing. Holt, Rinehart and Winston, New York.Google Scholar
[4] Birolini, A. (1994) Quality and Reliability of Technical Systems. Springer, Berlin.CrossRefGoogle Scholar
[5] Brok, J. F. C. (1987) Availability assessment of oil and gas production systems. Int. J. Quality Reliability Management 4, 2136.CrossRefGoogle Scholar
[6] Brouwers, J. J. H. (1986) Probabilistic descriptions of irregular system downtime. Reliability Eng. 15, 263281.Google Scholar
[7] Brouwers, J. J. H., Verbeek, P. H. J. and Thomson, W. R. (1986) Analytical system availability techniques. Reliability Eng. 17, 922.Google Scholar
[8] Cox, D. R. (1962) Renewal Theory. Methuen, London.Google Scholar
[9] Csenki, A. (1994) Cumulative operational time analysis of finite semi-Markov reliability models. Reliability Eng. Safety Syst. 44, 1725.CrossRefGoogle Scholar
[10] Csenki, A. (1995) An integral equation approach to the interval reliability of systems modelled by finite semi-Markov processes. Reliability Eng. Safety Syst. 47, 3745.Google Scholar
[11] Csenki, A. (1995) A new approach to the cumulative operational time for semi-Markov models of repairable systems. Preprint. Aston University.Google Scholar
[12] Funaki, K. and Yoshimoto, K. (1994) Distribution of total uptime during a given time interval. IEEE Trans. Reliability 43, 489492.Google Scholar
[13] Funnemark, E. and Natvig, B. (1985) Bounds for the availabilities in a fixed time interval for multistate monotone systems. Adv. Appl. Prob. 17, 638655.Google Scholar
[14] Haukås, H. (1994) Bounds on the system downtime distribution of a parallel system comprising two components. Note. Rogaland University Centre.Google Scholar
[15] Haukås, H. (1995) Contribution to availability analysis of monotone system. Ph.D. thesis. University of Oslo.Google Scholar
[16] Haukås, H. and Aven, T. (1994) Availability analysis of gas and oil production and transport systems. Paper presented at PSAM-II conference, San Diego, March, 1994.Google Scholar
[17] Haukås, H. and Aven, T. (1996) Formulae for the downtime distribution of a monotone system observed in a time interval. Reliability Eng. Safety Syst. (to appear).CrossRefGoogle Scholar
[18] Ross, S. M. (1970) Applied Probability Models with Optimization Applications. Holden-Day, San Francisco.Google Scholar
[19] Ross, S. M. (1975) On the calculation of asymptotic system reliability characteristics. In Fault Tree Analysis , ed Barlow, R. E., Fussel, J. B. and Singpurwalla, N. D. SIAM, Philadelphia.Google Scholar
[20] Takács, L. (1957) On certain sojourn time problems in the theory of stochastic processes. Acta Math. Acad. Scientiarum Hungaricae 8, 169191.Google Scholar
[21] Taylor, H. M. and Karlin, S. (1984) An Introduction to Stochastic Modeling. Academic Press, New York.Google Scholar