@ARTICLE{Dobrucki_Andrzej_Sound-Absorbing_2010,
 author={Dobrucki, Andrzej and Żółtogórski, Bronisław and Pruchnicki, Piotr and Bolejko, Romuald},
 volume={vol. 35},
 number={No 2},
 journal={Archives of Acoustics},
 pages={157-164},
 howpublished={online},
 year={2010},
 publisher={Polish Academy of Sciences, Institute of Fundamental Technological Research, Committee on Acoustics},
 abstract={The physical phenomena occurring in sound-absorbing and insulating enclosures are subject of the present paper. These phenomena are: absorption in air and by the sound-absorbing material covering the walls and the coincidence effect. The absorption in the air can be neglected in small size enclosures for low ultrasonic frequencies (20-30 kHz). The coincidence plays a role in decrease of the sound insulation, however the main role play the leaks. The boards made of ceramic fibers have been chosen as the optimal sound-absorbing material. They are dense and have deeply porous structures. The enclosure for insulation of 20-kHz noise produced by a welding machine has been designed and manufactured, and reductions of 25 dB of peak and Leq levels have been achieved.},
 type={Artykuły / Articles},
 title={Sound-Absorbing and Insulating Enclosures for Ultrasonic Range},
 URL={http://www.czasopisma.pan.pl/Content/107541/PDF-MASTER/71.pdf},
 doi={10.2478/v10168-010-0014-4},
 keywords={ultrasonic noise, sound absorbing and insulating enclosure, welder},
}