A novel strategy for redundant components in reliability--redundancy allocation problems

ABSTRACT

This article presents a new interpretation and formulation of the Reliability–Redundancy Allocation Problem (RRAP) and demonstrates that solutions to this new problem provide distinct advantages compared with traditional approaches. Using redundant components is a common method to increase the reliability of a system. In order to add the redundant components to a system or a subsystem, there are two traditional types of strategies called active and standby redundancy. Recently a new redundancy strategy, called the “mixed” strategy, has been introduced. It has been proved that in the Redundancy Allocation Problem (RAP), this new strategy has a better performance compared with active and standby strategies alone. In this article, the recently introduced mixed strategy is implemented in the RRAP, which is more complicated than the RAP, and the results of using the mixed strategy are compared with the active and standby strategies. To analyze the performance of the new approach, some benchmark problems on the RRAP are selected and the mixed strategy is used to optimize the system reliability in these situations. Finally, the reliability of benchmark problems with the mixed strategy is compared with the best results of the systems when active or standby strategies are considered. The final results show that the mixed strategy results in an improvement in the reliability of all the benchmark problems and the new strategy outperforms the active and standby strategies in RRAP.

Keywords:

• Reliability optimization
• reliability-redundancy allocation problems
• mixed redundancy strategy
• modified version of genetic algorithm

Additional information

Notes on contributors

Mostafa Abouei Ardakan

Mostafa Abouei Ardakan is an Assistant Professor in the Department of Industrial Engineering, Faculty of Engineering, Kharazmi University, Tehran, Iran. He received M.S. and Ph.D. degrees in Industrial Engineering from Isfahan University of Technology, Isfahan, Iran. He also received a B.S. degree in Industrial Engineering from Yazd University, Yazd, Iran. His current research involves reliability optimization, quality control, scheduling problems, and applications of operations research with a focus on complex systems.

Mohammad Sima

Mohammad Sima received B.S. and M.S. degrees in Mechanical Engineering from Amirkabir University of Technology and K. N. Toosi University of Technology, respectively. He also holds M.S. and Ph.D. degrees in Industrial and Systems Engineering from Rutgers University. He is a visiting Assistant Professor in the Department of Industrial Engineering at Lamar University. His research interests lie in manufacturing processes, computational mechanics, reliability prediction and optimization, and maintenance modeling and optimization. He is a member of ASME and SME.

Ali Zeinal Hamadani

Ali Zeinal Hamadani received his M.Sc. in Applied Statistics from Sussex University and Ph.D. in Industrial Technology from Bradford University, England. He is a Professor in the Department of Industrial Engineering at Isfahan University of Technology, Isfahan, Iran. His research interests lie in the areas of statistics, quality control, multivariate statistical analysis, data mining, and reliability modeling. He has numerous publications in international journals and conferences. He has considerable experience of consulting with many industries in Iran.

David W. Coit

David W. Coit received a B.S. degree in Mechanical Engineering from Cornell University, an MBA from Rensselaer Polytechnic Institute, and M.S. and Ph.D. degrees in Industrial Engineering from the University of Pittsburgh. He is a Professor in the Department of Industrial & Systems Engineering at Rutgers University. His current research involves reliability prediction & optimization, risk analysis, and multi-objective optimization considering uncertainty. His research has been funded by NSF, U.S. Navy, U.S. Army, QNRF, power utilities, and industry. He also has over 10 years of experience working for IIT Research Institute (IITRI), Rome, New York, USA (now called Alion Science and Technology), where he was a reliability analyst, project manager, and an engineering group manager. In 1999, he was awarded a CAREER grant from NSF to study reliability optimization. He is the past president for both the Quality Control & Reliability Engineering and Operations Research divisions of the Institute of Industrial Engineers. He is a member of IIE, INFORMS, and IEEE.