Gearboxes and bearings play an important role in industries for motion and torque transmission machines. Therefore, early diagnoses are sought to avoid unplanned shutdowns, catastrophic damage to the machine or human losses; additionally, an appropriate diagnosis contributes to increase productivity and reduce maintenance costs. This paper addresses a methodological framework for the diagnosis of multi-faults in rotating machinery through the use of features rankings. The classification uses K nearest neighbors and random forest, based on the information that comes from the measured vibration signal. Thirty features in time domain are calculated from the vibration signal, twenty-four features commonly used in fault diagnosis in rotating machinery, and six features are used from the field of electromyography. Feature ranking methods such as ReliefF algorithm, Chi-Square, and Information Gain are used to select the ten most relevant features, the same ones that enter the classifiers. Five databases were used to validate the proposed methodological framework. The results show good accuracy in classification for the five databases; furthermore, in all the databases in the first ten features ranked by the three rankings methods are present at least two nonconventional features.

This paper addresses the path followed by two private higher education institutions (HEI) in Colombia towards achieving carbon neutrality. The methodology followed by these universities to achieve a carbon-neutral certification, based on the Greenhouse Gas (GHG) Protocol, is first described. The process of developing the GHG inventory, projected towards the carbon neutrality of these organisations while using the standard ISO 14064:2006, involved a series of steps that were consolidated in three phases: (i) definition of the scope, collection of data and emissions quantification; (ii) analysis of results and mitigation actions; and (iii) verification and compensation strategies. Results for the HEIs are shown in terms of the organisational context, carbon footprint measurement, reduction, verification, and compensation. The case is presented for Universidad Pontificia Bolivariana, a multi-campus university that became the first carbon-neutral university in Latin America in 2017, and Universidad Ean, a single-campus university that became the second carbon-neutral university in Colombia in 2021, as verified by the Colombian Institute of Technical Standards and Certification (ICONTEC). This work shows that universities can play a key role in regional and global agendas with their contribution through the incorporation of sustainability strategies, since HEIs can not only achieve carbon neutrality, but they can help other organisations by delivering graduates who are aware of sustainability and provide specific training towards building a sustainability culture, which is needed for regenerative development.