We congratulate Asadi, Hashemi, and Balakrishnan for a comprehensive review of age-based maintenance strategies thorough study the statistic “signature” multi-component coherent systems. Among many contributions, Balakrishnan's paper also provides taxonomic framework with which to categorize classify plethora models. Section 2 is great importance, providing new researchers reliable nomenclature...

The National Bridge Stock of Iran consists of about 330,000 bridges, of which around 50% are older than 30 years. Since 2010, Iran Road Maintenance & Transportation Organization has started implementing a comprehensive Bridge Management System in order to manage this aged stock efficiently. To predict future conditions of bridge stock, a heuristic numerical method is presented. This methodology...