In this work, we report a non-destructive and non-contacting ultrasound system with novel air-coupled transducer to continuously monitor the drying process of prickly pear (nopal) pads in lab environment. Compared conventional imaging spectroscopic methods or electrical-based approaches, ultrasound-based are non-invasive, cost-effective, suitable for large volume evaluation. The time-dependent ...

This paper describes a new ultrasonic measuring device called “W-Box”. It was developed based on the requirements of DFG Forschergruppe (research unit) CoDA for portable monitoring concrete specimens, models and actual structures using embedded transducers as well temperature humidity sensors. The W-Box can send pulses with variable frequency 50–100 kHz to one selectable transducer records sign...