“…Existing literature on maintenance policies for large equipment or products considers replacement as an option to enhance the reliability ( Ahmad & Kamaruddin, 2012;Dekker, Wildeman, & Van der Duyn Schouten, 1997;Pan & Thomas, 2010 ). In the area of maintenance decision making, the use of condition-based maintenance relies on the continuous or periodic monitoring of an in-use product ( Grall, Bérenguer, & Dieulle, 2002;Chen & Wu, 2007 ;& Alaswad & Xiang, 2017 ). Some researchers have extended the new maintenance paradigm by monitoring multiple in-use products without inventory considerations ( Hong, Zhou, Zhang, & Ye, 2014;Keizer, Teunter, & Veldman, 2016;Shafiee, Finkelstein, & Bérenguer, 2015;Tian & Liao, 2011 ;& Verbert, Schutter, & Babuška, 2017 ).…”