Stochastic Reliability Modeling and Optimization is the most fundamental topic in the board area of reliability and maintenance engineering, and still plays a significant role in industrial applications. In past, we have organized the similar titled special sessions in several locations such as The 2009 International Conference on Advanced Software Engineering & Its Applications (ASEA-2009), Jeju Island, Korea, December 10-12, 2009, The 2nd International Conference on Advanced Computer Science and Information Technology (AST-2010), Miyazaki, Japan, June 23-25, 2010, International Conference on Quality, Reliability, Maintenance, and Safety (QR2MSE 2011), Xi'an, China, June 17-19, 2011, The 7th International Conference on Mathematical Methods in Reliability - Methodology and Practice (MMR-2011), Beijing, China, June 20-14, 2011. Especially, the selected papers from the last two conferences were included in the monograph; Stochastic Reliability and Maintenance Modeling (T. Dohi and T. Nakagawa, eds.), Springer, 2013, and the special issue in Reliability Engineering and System Safety (vol. 116, 2013).
QR2MSE 2014 was held in Dalian, China, on July 22-25, 2014. At this well-attended conference, we organized a special session on Stochastic Reliability Modeling and Optimization, and accepted ten papers from China, Japan and Korea, through the peer-review process. Based on these conference papers and detailed discussion at the conference venue, we called for the extended papers with significant extension, in the Special Issue on Stochastic Reliability Modeling and Optimization, for inclusion in the International Journal of Performability Engineering (IJPE). Finally, we selected five submissions from the QR2MSE conference papers, in addition to two tutorial/invited papers from distinguished researchers.
All papers included in this special issue of IJPE have been peer reviewed by at least two referees. We are much pleased to accept seven high quality papers for this special issue and to provide the most recent research results in Stochastic Reliability Modeling and Optimization. It is known that stochastic modeling and optimization techniques are very useful for quantification and analysis of complex systems in real world, and are commonly used in both design and operational phases of engineering systems. We believe that the readers of this journal may be able to find new ideas and problems in the area of system performability analysis.
The first paper, which is an invited contribution, viz., Largeness Avoidance in Availability Modelling Using Hierarchical & Fixed-point Iterative Techniques’’ by H. Sukhwani, A. Bobbio, and K. S. Trivedi treats a practically important issue in availability modeling with large scaled Markov chains and proposes a sophisticated technique based on hierarchical modeling approach and Brouwer’s fixed-point algorithm.
The second invited paper, Survey of Replacement Policies for Parallel Systems with Newly Proposed Approaches by T. Nakagawa and X. Zhao is an excellent survey on some optimal replacement policies for parallel system with random number of components. It deals with the situation where the number of active components is known in advance and provides a new paradigm for optimal maintenance decision.
The remaining five papers are the extended versions and refereed contributions selected from the QR2MSE 2014 conference papers.
The third paper of this special issue, Converting a Multi-state System into a Family of Binary State Systems by F. Ohi concerns a mathematical theory to convert a multi-state system into a family of binary state systems. Since the multi-state system is essentially difficult through analytical treatment, the result will be useful to analyze complex multi-state systems.
The fourth paper, Magnitude Relation of the All-terminal Reliability of Network Systems by X. Xiao, Y. Chen, N. Takahashi, and H. Yamamoto describes the magnitude relation of the all-terminal reliability of network systems. Because it is useful to focus on the special property of complex network in computing the network reliability, their approach is validated theoretically and experimentally.
In the fifth paper, Optimal Data Transfer Strategies for the Automatic Hierarchized Storage within a Server System, the authors X. Zhao, S. Nakamura, and T. Nakagawa address the optimal data transfer strategies for automatic hierarchized storage within a server system. It is a good application of optimal maintenance theory to real computer systems and is related to the fault-tolerant computing.
The sixth paper, A Simulation-based Multi-Level Redundancy Allocation for a Multi-Level System, Y. J. Han, W. Y. Yun and J. Y. Lee considers a simulation-based multi-level redundancy allocation for a multi-level system. Though the underlying problem is difficult to treat analytically, the authors apply the well-defined simulation scheme and provide realistic solutions with application to the reliability engineering practice.
The final paper, M-SRAT: Metrics-based Software Reliability Assessment Tool by K. Shibata, K. Rinsaka, and T. Dohi develops a metrics-based software reliability assessment tool, called M-SRAT, and show through some illustrative examples that it is useful to assess the software reliability when not only software fault count data but also software metrics data are observed.
All the papers included in this special issue are the original contributions and are well-balanced between theoretical contributions and practical application.
Lastly, we like to thank Professor Krishna B. Misra, Editor-in-Chief of IJPE, for kind guidance, warm encouragement and his help from time to time to edit this special issue.
Tadashi Dohi, Hiroshima University, Japan
Won Young Yun, Pusan National University, Korea
ABOUT THE GUEST AUTHORS
Tadashi Dohi has been working as a full Professor in the Department of Information Engineering, Graduate School of Engineering, Hiroshima University since 2002. He received the B.S.E., M.S. and Ph.D. degrees in Engineering from Hiroshima University, Japan, in 1989, 1991and 1995, respectively. During 1992 and 2000, he was a Visiting Researcher in the Faculty of Commerce and Business Administration, University of British Columbia, Canada, and Hudson School of Engineering, Duke University, USA, respectively, on leave of absence from Hiroshima University. His research areas include reliability engineering, software reliability, dependable computing, performance evaluation and high assurance systems design. Professor Dohi has authored numerous publications in these areas. He is a member of IEICE, ORSJ, JAMS, ISCIE and IEEE. He also serves as a member of editorial boards of several international journals.
Won Young Yun is a Professor in the Department of Industrial Engineering, Pusan National University, Busan, Korea. He received his B.S. from Seoul National University in 1982 and an M.E. and Ph.D. from the Department of Industrial Engineering, Korea Advanced Institute of Science and Technology (KAIST) in 1984 and 1988, respectively. He was a Visiting Researcher in the University of Birmingham, U.K. and Queensland University of Technology, Australia, in 1993 and 1999 respectively. His research interests include optimization problems in system reliability, maintenance, warranty, and inland container repositioning in which simulation and meta-heuristics are used to find optimal solutions.