Author(s):
1. Hristo Hristov, Technical University of Gabrovo, Department of Physics, Chemistry and Ecology 4 Hadzhy Dimitar str., Bulgaria
2. Georgi Iliev, Technical University of Gabrovo, Center of competence "Smart mechatronic, eco-and energy-saving syst, Bulgaria
3. Plamen Bonev, Technical University of Gabrovo, Center of competence "Smart mechatronic, eco-and energy-saving syst, Bulgaria

Applied paper from author