January 14, 2022 Klemen Bučar of the Jožef Stefan Institute and Jiří Šperka of the Czech Metrology Institute gave two oral presentations at the online conference OpenAlt 2021 organized on 6th November 2021. Klemen presented about calibration of a DIY Low-cost Aerosol Detector and Jiří presented about metrology of aerosol particles and AEROMET II project. Conference website can be found here.