Vibro-acoustic nonlinear wave modulations are investigated experimentally in a cracked aluminum plate. The focus is on the effect of low-frequency vibration excitation on modulation intensity and associated nonlinear wave interaction mechanisms. The study reveals that energy dissipation – not opening–closing crack action – is the major mechanism behind nonlinear modulations. The consequence is that relatively weak strain fields can be used for crack detection in metallic structures. A clear link between modulations and thermo-elastic coupling is also demonstrated, providing experimental evidence for the recently proposed non-classical, nonlinear vibro-acoustic wave interaction mechanism.

In this paper we examine in detail the multiple responses of a novel vibrational energy harvester composed of a vertical bistable beam whose complex non-linear behavior is tuned via magnetic...

The paper aims at demonstrating the cutting-edge tool for machine learning models explainability leveraging LightGBM modelling. The proposed methodology improves inference performance, training time and significantly reduces the "fitting-to-noise" problem for complex datasets, and additionally, grants more insight into model predictions. Discussed methodology is versatile and finds applications in processing big data sets from different fields of science, ranging from econometry to medical or SHM applications, in which networks of MEMS sensors are used.