“…As they are written by humans, the unstructured, nosily text is treated with natural language processing in successive stages to perform the PdM task. A similar approach, but applied to vehicles, is followed in Chen, Liu, et al (2021): instead of using sensor connectivity, it combines both maintenance records and weather, traffic and terrain factors, captured by the geographical information system of the vehicles fleet. In some works (Calabrese et al, 2020; Dangut et al, 2021; Koca et al, 2020; Pezze et al, 2021), the use of alarms or warnings designed for human interaction is proposed as a cheaper alternative to the implantation of sensors.…”