A Multi-Objective Optimization of Preventive Maintenance for Multi-State Aging Systems  
Author Chun-Ho Wang


Co-Author(s) Chao-Hui Huang


Abstract This paper presents a repairable multi-state redundant aging system with warm-standbys to establish a multi-objective preventive maintenance (MOPM) model from the perspective of components. The system configured with warm-standbys is widely seen in a complicated redundant structure. Primary components and standbys can be designed to feature the repairable multi-state property. PM certainly plays a crucial role in improving system reliability and lowering lifecycle costs. In the established MOPM model, system availability and total maintenance cost are the two objectives to be optimized simultaneously, whereas the decision variables involve maintenance activities once the components fall into a degraded state. The proposed approach evaluates the two-optimization objectives integrating nonhomogeneous continuous-time Markov models (NHCTMMs) into the universal generating function technique to address the difficulty in solving large-scale NHCTMMs. The related Markov reward models for each component are also determined to calculate the total maintenance cost. The optimized diverse non-dominated solutions on the efficient frontier provide distinguished PM alternatives. Engineers can simply determine the most appropriate PM alternative in concert with practical requirements. A real case of a multistate water cooling system with aging components in standby configuration demonstrates the efficacy of the proposed approach.


Keywords Standbys; redundant multi-state aging system, multi-objective optimization, universal generating function NHCTMMs
    Article #:  24111
Proceedings ISSAT International Conference on Reliability and Quality in Design 2018
August 2-4, 2018 - Toronto, Ontario, Canada