The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Preferred masking levels of water sounds according to various noise background levels in small scale open plan offices

소규모 개방형 사무실 배경 소음 레벨에 따른 최적 물소리 마스킹 레벨

  • 김태희 (충남대학교 건축공학과) ;
  • 이상현 (충남대학교 건축공학과) ;
  • 윤채현 (충남대학교 건축공학과) ;
  • 심효원 (충남대학교 건축공학과) ;
  • 홍주영 (충남대학교 건축공학과)
  • Received : 2023.07.18
  • Accepted : 2023.09.21
  • Published : 2023.11.30
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Abstract

This study aims to investigate the preferred sound level of water sound for various levels of open-plan-office noise regarding soundscape quality and speech privacy. And assessment of the work efficiency of the water sound. For the laboratory experiment, office noise was recorded using a binaural microphone in a real open-plan office. For the assessment of the soundscape quality and speech privacy, Overall Soundscape Quality (OSQ) and Listening Difficulty (LD) were evaluated under three different sound levels (55 dBA, 60 dBA, and 65 dBA) and five different signal-to-noise ratios (SNR -10 dB, -5 dB, 0 dB, +5 dB, and +10 dB). After the evaluation, the preferred SNR was proposed according to OSQ and LD. For the assessment of to work efficiency of water sound, this study evaluated the cognitive performance of both of the condition noise only and combine the water sound with office noise. The results showed that LD increased as the water sound level increased, but OSQ decreased. When the water sound level was more than the office noise level, the OSQ decreased from noise only. Therefore, considering OSQ and LD, the preferred SNR of water sound was -5 dB for all noise levels. At the preferred level of water sound, the cognitive performance results were shown to decrease at 55 dBA compared to noise only, but at 60 dBA and 65 dBA combine the water sound results were increased than the noise only.

개방형 사무실에서 소음과 스피치 프라이버시 문제는 꾸준히 제기되어 왔다. 이러한 개방형 사무실의 문제점을 해결하기 위한 마스킹 음원에 대한 연구가 필요하다. 따라서 본 연구에서는 청취 실험을 통하여, 쾌적한 물소리를 마스킹 음원으로 제안하고자 한다. 먼저 다양한 소음 레벨에 대하여 음환경 쾌적도와 스피치 프라이버시를 고려한 최적 물소리 레벨에 대하여 고찰하고자 한다. 이후 최적 레벨의 물소리 도입이 업무효율성에 미치는 영향을 검정하고자 한다. 청취실험에서 사용된 사무실 소음은 실제 개방형 사무실에서 바이노럴 마이크를 활용해 녹음하였고, 헤드폰을 통해 피험자들에게 제시하였다. 청취실험 음원은 각각 3개의 등가 배경소음레벨(55 dBA, 60 dBA, 65 dBA)과 5개의 신호대잡음비[Signal to noise ratio(SNR) -10 dB, -5 dB, 0 dB, +5 dB, +10 dB]의 조합로 구성하였고, 각 음원에 대한 주관평가로 전체적인 음환경 쾌적도(Overall Soundscape Quality, OSQ)와 듣기 어려운 정도(Listening Difficulty, LD)를 평가하였다. 평가 결과 배경음 보다 물소리가 커질수록 LD는 증가하였지만 OSQ는 감소하였다. 특히 물소리가 사무실 소음 보다 클경우 도입 전보다 OSQ가 감소하였다. 따라서 OSQ와 LD를 고려하였을 때 소음레벨별 최적 SNR은 모든 소음레벨에 대하여, -5 dB로 나타났다. 이후 업무 효율성을 평가하기 위하여, 최적 레벨의 물소리 도입 전후에 인지능력(Cognitive performance)을 평가하였다. 평가 결과 최적 레벨의 물소리를 도입할 경우, 배경소음이 55 dBA에서는 인지능력평가 결과가 물소리 도입 전에 비해 감소하는 것으로 나타났으나, 60 dBA와 65 dBA에서는 증가하는 것으로 나타났다.

Keywords

Acknowledgement

이 연구는 한국연구재단 연구비 지원에 의한 결과의 일부임(과제번호: NRF-2022R1C1C1008066).

References

  1. J. H. Jeong, "Speech intelligibility, and speech privacy assessment indicators for indoor spaces" (in Korean), Trans. Korean Soc. Noise Vib. Eng. 27, 22-25 (2017).
  2. E. J. Sander, C. Marques, J. Birt, M. Stead, and O. Baumann, "Open-plan office noise is stressful: Multimodal stress detection in a simulated work environment," J. Manag. Organ. 27, 1021-1037 (2021).
  3. E. S. Bernstein and S. Turban, "The impact of the 'open' workspace on human collaboration," Philos. Trans. R. Soc. B, 373, 20170239 (2018).
  4. J. S. Kim and R. Dear, "Workspace satisfaction: The privacy-communication trade-off in open-plan offices," J. Environ. Psychol. 36, 18-26 (2013). https://doi.org/10.1016/j.jenvp.2013.06.007
  5. S. M. Lee, H. S. Song, J. H. Kim, S. H. Kim, and J. K. Ryu, "Subjective evaluation of acoustic environment in open-plan office" (in Korean), Proc. KSNVE Annual Spring Conf. 75 (2020).
  6. Y. J. Kim, S. K. Yum, S. H. Lee, D. S. Song, and Y. S. Kim, "Improvement of speech privacy in open plan offices using articulation index" (in Korean), JAIK, 26, 309-316 (2010).
  7. B. K. Lee, P. J. Lee, J. Y. Hong, and J. Y. Jeon, "Prediction of acoustics for open plan office according to the changes of architectural element" (in Korean), Proc. KSNVE Annual Autumn Conf. 285-286 (2010).
  8. P. J. Lee, J. Y. Hong, B. K. Lee, and J. Y. Jeon, "Measures for assessing speech privacy of open plan offices" (in Korean), Proc. KSNVE Annual Autumn Conf. 283-284 (2010).
  9. V. Hongistob, J. Varjo, D. Oliva, A. Haapakangas, and E. Benway, "Perception of water-based masking sounds-long-term experiment in an open-plan office," Front. Psychol. 8, 1-14 (2017).
  10. ISO 12913-1:2014 Acoustics - Soundscape - Part 1: Definition and Conceptual Framework, 2014.
  11. A. L. Brown, "Soundscapes and environmental noise management," Noise Control Eng. J. 58, 493-500 (2010). https://doi.org/10.3397/1.3484178
  12. J. Y. Jeon, P. J. Lee, J. You, and J. Kang, "Perceptual assessment of quality of urban soundscapes with combined noise sources and water sounds," J. Acoust. Soc. Am. 127, 1357-1366 (2010). https://doi.org/10.1121/1.3298437
  13. J. You, P. J. Lee, and J. Y. Jeon, "Evaluating water sounds to improve the soundscape of urban areas affected by traffic noise," Noise Control Eng. J. 58, 477-483 (2010). https://doi.org/10.3397/1.3484183
  14. J. Y. Jeon, P. J. Lee, J. You, and J. Kang, "Acoustical characteristics of water sounds for soundscape enhancement in urban open spaces," J. Acoust. Soc. Am. 131, 2101-2109 (2012). https://doi.org/10.1121/1.3681938
  15. L. Galbrun and T. T. Ali, "Perceptual assessment of water sounds for road traffic noise masking," Proc. Acoust. 2147-2152 (2012).
  16. J. Y. Hong, B. Lam, Z. T. Ong, K. Ooi, W. S. Gan, J. Kang, S. Yeong, I. Lee, and S. T. Tan, "The effects of spatial separations between water sound and traffic noise sources on soundscape assessment," Build. Environ. 167, 106423 (2020).
  17. J. Y. Hong, B. Lam, Z. T. Ong, K. Ooi, W. S. Gan, J. Kang, S. Yeong, I. Lee, and S. T. Tan, "Effects of contexts in urban residential areas on the pleasantness and appropriateness of natural sounds," Sustain. Cities Soc. 63, 102475 (2020).
  18. J. Y. Hong, Z. T. Ong, B. Lam, K. Ooi, W. S. Gan, J. Kang, J. Feng, and S. T. Tan, "Effects of adding natural sounds to urban noises on the perceived loudness of noise and soundscape quality," Sci. Total Environ. 711, 134571 (2020).
  19. J. Y. Hong, Z. T. Ong, B. Lam, K. Ooi, W. S. Gan, J. Kang, S. Yeong, I. Lee, J. Feng, and S. Tiong Tan, "A mixed-reality approach to soundscape assessment of outdoor urban environments augmented with natural sounds," Build. Environ. 194, 107688 (2021).
  20. J. Kang, "On the diversity of urban waterscape," Proc. Acoust. 3533-3538 (2012).
  21. Artemis-Suite, https://www.head-acoustics.com/products/analysis-software/artemis-suite, (Last viewed September 1, 2023).
  22. F. Aletta, J. Kang, and O. Axelsson, "Soundscape descriptors and a conceptual framework for developing predictive soundscape models," Landsc. Urban Plan. 149, 65-74 (2016). https://doi.org/10.1016/j.landurbplan.2016.02.001
  23. H. Sato, M. Morimoto, S. Ohtani, Y. Hoshino, and H. Sato, "Subjective evaluation of speech privacy at consulting rooms in hospitals: Relationship between feeling evoked by overhearing speech and word intelligibility score," Appl. Acoust. 124, 38-47 (2017). https://doi.org/10.1016/j.apacoust.2017.03.020
  24. Cognitive Fun, http://cognitivefun.net/test/2, (Last viewed November 4, 2022).
  25. M. J. Zajano and A. Gorman, "Stroop interference as a function of percentage of congruent items," Percept. Mot. Skills, 63, 1087-1096 (1986). https://doi.org/10.2466/pms.1986.63.3.1087
  26. K. G. Beal and H. J. Khamis, "Statistical analysis of a problem data set : correlated observations," Condor, 92, 248-251 (1990). https://doi.org/10.2307/1368411
  27. J. M. Bae and G. H. Park, Dr Bae's Healthcare Statistics (Hannarae, Seoul, 2012), pp. 245-263.
  28. Jamovi: The jamovi project (Version 2.3), https://www.jamovi.org, (Last viewed May 24, 2023).
  29. M. Mazziotta and A. Pareto, "Normalization methods for spatio-temporal analysis of environmental performance: Revisiting the min-max method," Environmetrics, 33, e2730 (2022).