| Autor: |
Keiji Kawai, Midori Ishizawa, Yuuki Matsufuji |
| Předmět: |
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| Zdroj: |
INTER-NOISE & NOISE-CON Congress & Conference Proceedings; 2023, Vol. 265 Issue 2, p715-720, 6p |
| Abstrakt: |
Japanese national or local governments have not published any standard for acoustic performance of classrooms and this is reflected by the rare consideration of sound absorption in classrooms. A kindergarten classroom, targeted in this study, was found to be highly reverberant (V = 200 m3, RT = 1.0 s at 1 kHz) because the room was originally an outdoor space of ground floor pilotis and converted into a classroom by constructing concrete walls between the columns with the fire-resistant hard ceiling panels remained. The author proposed a temporary installation of sound absorbing material and to conduct a field experiment to examine and experience the effect of sound absorption. Sound absorbers were attached on the ceiling and the walls to reduce the RT to 0.5 s. By this, the slope of doubled distance attenuation increased from 1.5 dB to 2.3 dB, which should mitigate the confusion of speeches by children in the room. The result of sound level monitoring indicated 6-7 dB decrease at 1-2 kHz in the absorbed condition, which is greater than the 3.8 dB decrease measured in the unoccupied condition using a loudspeaker source. Also, the children's utterances of lunch prayer were more synchronized in the absorbed condition. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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