Abstract
This special issue collects 20 papers, reflecting the breadth of current research in system reliability and safety engineering. Together, they highlight both the continued importance of foundational reliability theory and the growing influence of data-driven and intelligent methods in modern engineering applications. Across the issue, readers will find contributions on system reliability modelling, resource allocation, reliability demonstration testing, maintenance optimisation, degradation analysis, fault diagnosis, remaining useful life prediction, accelerated degradation testing, software reliability, quality evaluation and risk assessment under uncertainty.