Abstract
Bathtub-shaped failure intensity is typical for large-scaled repairable systems with a number of different failure modes. Sometimes, repairable systems may exhibit a failure pattern different from the traditional bathtub shape, due to the existence of multiple failure modes. This study proposes two superposed Poisson process models with modified bathtub intensity functions to capture this kind of failure pattern. The new models are constructed by the superposition of the generalized Goel–Okumoto process and power law process (or log-linear process). The proposed models can be applied to masked failure-time data from repairable systems where the modes of collected failure-times are unobserved or unavailable. Bayesian posterior computation algorithms based on the data augmentation method are developed for the inference on the parameters or their functions of the superposed Poisson process models. This study also examines the best model selection among the candidate models in the Bayesian framework and modeling check using the residuals. A practical case study with a data set of unscheduled maintenance events for complex artillery systems illustrates potential applications of the proposed models for the purpose of reliability prediction for the repairable systems.
Acknowledgments
The authors are grateful to three referees and AE for their careful reading and helpful suggestions.
Additional information
Funding
Notes on contributors
Tao Yuan
Tao Yuan received a BE degree in thermal engineering from Tsinghua University, China; an MS degree in aerospace engineering and an ME degree in industrial engineering from Texas A&M University, College Station; and a PhD degree in industrial engineering from the University of Tennessee, Knoxville. He is a professor in the Department of Industrial and Systems Engineering at Ohio University. His research interests mainly include reliability modeling and prediction, as well as reliability testing and characterization for electronic devices. He is a member of IISE, INFORMS and IEEE.
Tianqiang Yan
Tianqiang Yan earned his BE degree in electronic information science and technology at Nanjing Agricultural University, China. He also received an MS degree in industrial and system engineering from the Russ College of Engineering and Technology at Ohio University. His primary research interests involve reliability modeling and data analysis.
Suk Joo Bae
Suk Joo Bae is a professor in the Department of Industrial Engineering at Hanyang University, Seoul, South Korea. He received his PhD degree from the School of Industrial and Systems Engineering at the Georgia Institute of Technology in 2003. He served as a reliability engineer at Samsung SDI, Korea from 1996 to 1999. His research interests are centered on reliability evaluation of light displays, nanodevices, and battery systems including fuel cells via accelerated life and degradation testing, fault diagnoses and prognostics for condition-based maintenance, and process monitoring for large-volumed on-line sensing data. He has published more than 60 papers in journals such as Technometrics, Journal of Quality Technology, IISE Transactions, Reliability Engineering & System Safety, and IEEE Transactions on Reliability. Currently he is an associate editor of IEEE Transactions on Reliability. He is a member of INFORMS and IEEE.