Journal of Industrial Technology (산업기술연구)

Kangwon National University, Institute of Industrial Technology (강원대학교 산업기술연구소)
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Proposing a simple procedure for predicting the acoustical conditions in occupied classrooms from the measured unoccupied values

공석 시 측정값을 활용한 만석 시 강의실의 음향상태 예측법

  • Ahn, Jae-Young (Samwoo ANC Acoustics & Noise Consulting, Research Fellow) ;
  • Choi, Young-Ji (Department of Architectural Engineering, Kangwon National University)
  • Received : 2021.09.06
  • Accepted : 2021.10.19
  • Published : 2021.10.31
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Abstract

This work proposes a simple method to use the added absorption per person values to predict the expected values of the acoustical conditions in occupied classrooms. This method is based on the effects of the values of added absorption per person on the unoccupied total absorption values of the classrooms and on other room acoustical parameters. The total sound absorption in an unoccupied classroom can be calculated from measured reverberation times in the classroom. The expected occupied absorption can be calculated using equation which was obtained in a previous study (Choi, 2017) by fitting a linear regression line to a plot of total occupied absorption versus the corresponding unoccupied total absorption values measured in 12 university classrooms. The ratios of occupied-to-unoccupied sound absorption are used to predict increments in the values of acoustical parameters that result when occupants are added to the rooms.

Keywords

Acknowledgement

I am very grateful to professors, and undergraduate students in the school of engineering at Kangwon National University who volunteered for the classroom measurements. This work was supported by National Research Foundation of Korea funded by the Korean Government (2015R1D1A1A01056575, 2018R1A2B6001279).

References

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