Pozvánka na přednášku Time-Frequency Analysis for Acoustic Signals 5
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چکیده
A. Obecná a lineární akustika předseda – Bednařík zástupce – Červenka B. Ultrazvuk a akustické emise předseda – Šlegrová zástupce – Plocek C. Hluk a vibrace předseda – Strnad zástupce – Hellmuth D. Prostorová, stavební a urbanistická akustika předseda – Meller zástupce – Ryndová E. Zpracování a záznam akustických signálů předseda – Salava F. Psychoakustika, fyziologická akustika a akustika hudby a řeči předseda – Štěpánek During the realisation of a Czech round-Robin test concerning the determination of the sound absorption coefficient in an impedance tube, additional measurements were made with small modifient test speciments. It was found that the change in the material has, greater influence than the mounting. It was also confirmed that the mineral wool has at the middle frequency range, a dip in the values of the sound absorbtion coefficient. díky řídkosti a nízké plošné hmotnosti neovlivňuje. Tabulka 1: Akustické vlastnosti prázdné trubice – naměřené hodnoty činitele zvukové pohltivosti α pro kolmý dopad zvuku, poměru stojatých vln s a hluku pozadí L 0
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تاریخ انتشار 2004