The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Effect of noise and reverberation on subjective measure of speech transmission performance for elderly person with hearing loss in residential space

주거 공간에서 고령자 청력손실을 고려한 소음 및 잔향에 따른 음성 전송 성능의 주관적 평가

  • Received : 2018.07.17
  • Accepted : 2018.09.20
  • Published : 2018.09.30
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Abstract

This study investigated the effect of noise and reverberation on subjective measure of speech transmission performance for elderly person with hearing loss in residential space through listening test. Floor impact, road traffic, airborne, and drainage noise were employed as the residential noise, and several impulse responses were obtained through room acoustical computer simulation for an apartment building. Sound sources for the listening test consisted of residential noises and speech sounds for boh the young (the original sound) and the aged (the sound filtered out by filters with frequency responses of hearing loss of 65 years elderly person). In the listening test, subjects evaluated speech intelligibility and listening difficulty for the presented word ($L_{Aeq}$ 55 dB) at three noise levels ($L_{Aeq}$ 30, 40, 50 dB) and three reverberation times (0.5, 1.0, 1.5 s). Results showed that the residential space with noise level lower than equal to 50 dB ($L_{i,Fmax,AW}$) for jumping noise and 40 dB ($L_{Aeq}$) for road traffic, airborne, and drainage noise had speech intelligibility of 90 % and over and listening difficulty of 30 % and below. Speech intelligibility and listening difficulty for the aged sound source was shown to be 0 % ~ 5 % lower and 2 % ~ 20 % higher than those for the young sound source, respectively.

본 논문은 주거공간에서 고령자 청력손실을 고려한 소음 및 잔향에 따른 음성 전송 성능을 청취실험을 통해 평가하였다. 주거환경 소음으로 바닥충격음, 교통소음, 공기전달음과 배수소음을 대상으로 하였으며, 공동주택의 잔향환경을 모사하기 위해 실내음향 컴퓨터시뮬레이션을 실시하여 충격응답를 추출하였다. 청취실험 음원은 고령자 청력손실(65세 남성)을 반영하기 위해 소음 및 단어 음원의 고주파대역의 음압레벨을 저감시킨 음원(고령자 음원)과 정상청력을 반영한 원음(청년 음원)을 대상으로 하였다. 청취실험은 각각 3개의 소음레벨($L_{Aeq}$ 30, 40, 50 dB)과 잔향시간(0.5, 1.0, 1.5 s)을 갖는 음환경 조건에서 제시된 단어($L_{Aeq}$ 55 dB)의 음성요해도(speech intelligibility)와 듣기 어려운 정도(listening difficulty)를 평가하는 것으로 하였다. 청취실험 결과, 음성레벨이 55 dB($L_{Aeq}$)일 때 잔향시간 1.0 s 이하 조건에서 충격소음(점핑음) 50 dB($L_{i,Fmax,AW}$)와 정상소음(도로, 음악, 배수 소음) 40 dB($L_{Aeq}$) 이하의 소음레벨에서는 고령자 및 청년 음원 모두 90 % 이상의 음성요해도와 30 % 이하의 듣기 어려운 정도를 확보할 수 있을 것으로 판단된다. 고령자 청력손실을 반영한 고령자 음원의 경우 청년 음원 보다 음성요해도는 0 % ~ 5 % 낮았고 듣기 어려운 정도는 2 % ~ 10 % 높은 것으로 나타났다.

Keywords

References

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