{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T13:28:47Z","timestamp":1769002127034,"version":"3.49.0"},"reference-count":25,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T00:00:00Z","timestamp":1683504000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"JSPS KAKENHI","doi-asserted-by":"publisher","award":["JP22K18778"],"award-info":[{"award-number":["JP22K18778"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The sound amplification ratios of sealed air chambers with different shapes were quantitatively compared to design a body-conduction microphone to measure animal scratching sounds. Recently, quantitative monitoring of scratching intensity in dogs has been required. We have already developed a collar with a body-conduction microphone to measure body-conducted scratching sounds. However, the air chamber, one of the components of the body-conduction microphone, has not been appropriately designed. This study compared the amplification ratios of air chambers with different shapes through numerical analysis and experiments. According to the results, the horn-shaped air chamber achieved the highest amplification performance, at least for sound frequencies below 3 kHz. The simulated amplification ratio of the horn-shaped air chamber with a 1 mm height and a 15 mm diameter was 52.5 dB. The deformation of the bottom of the air chamber affected the amplification ratio. Adjusting the margin of the margined horn shape could maintain its amplification ratio at any pressing force. The simulated and experimental amplification ratios of the margined horn-shaped air chamber were 53.4 dB and 19.4 dB, respectively.<\/jats:p>","DOI":"10.3390\/s23094565","type":"journal-article","created":{"date-parts":[[2023,5,9]],"date-time":"2023-05-09T01:34:26Z","timestamp":1683596066000},"page":"4565","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Margined Horn-Shaped Air Chamber for Body-Conduction Microphone"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7094-227X","authenticated-orcid":false,"given":"Shun","family":"Muramatsu","sequence":"first","affiliation":[{"name":"Department of Precision Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"}]},{"given":"Yuki","family":"Kohata","sequence":"additional","affiliation":[{"name":"Department of Precision Engineering, Faculty of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"}]},{"given":"Emi","family":"Hira","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medical Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan"}]},{"given":"Yasuyuki","family":"Momoi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medical Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6542-2800","authenticated-orcid":false,"given":"Michitaka","family":"Yamamoto","sequence":"additional","affiliation":[{"name":"Department of Precision Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"},{"name":"Department of Precision Engineering, Faculty of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6502-7819","authenticated-orcid":false,"given":"Seiichi","family":"Takamatsu","sequence":"additional","affiliation":[{"name":"Department of Precision Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"},{"name":"Department of Precision Engineering, Faculty of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"}]},{"given":"Toshihiro","family":"Itoh","sequence":"additional","affiliation":[{"name":"Department of Precision Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"},{"name":"Department of Precision Engineering, Faculty of Engineering, The University of Tokyo, Tokyo 113-8656, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1057\/s41599-020-00649-x","article-title":"Human\u2013dog relationships during the COVID-19 pandemic: Booming dog adoption during social isolation","volume":"7","author":"Morgan","year":"2020","journal-title":"Humanit. Soc. Sci. Commun."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"77-e25","DOI":"10.1111\/vde.12107","article-title":"Validation of the canine atopic dermatitis extent and severity index (CADESI)-4, a simplified severity scale for assessing skin lesions of atopic dermatitis in dogs","volume":"25","author":"Olivry","year":"2014","journal-title":"Vet. Dermatol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1111\/j.1365-3164.2006.00537.x","article-title":"Objective measurement of pruritus in dogs: A preliminary study using activity monitors","volume":"17","author":"Nuttall","year":"2006","journal-title":"Vet. Dermatol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1111\/j.1365-3164.2007.00616.x","article-title":"Development of an owner-assessed scale to measure the severity of pruritus in dogs","volume":"18","author":"Hill","year":"2007","journal-title":"Vet. Dermatol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1111\/j.1365-3164.2007.00608.x","article-title":"Repeatability and reproducibility of numerical rating scales and visual analogue scales for canine pruritus severity scoring","volume":"18","author":"Plant","year":"2007","journal-title":"Vet. Dermatol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"S109","DOI":"10.1016\/S0091-6749(99)70052-7","article-title":"Itching and the atopic skin","volume":"104","author":"Koblenzer","year":"1999","journal-title":"J. Allergy Clin. Immunol."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Harvey, N.D., Craigon, P.J., Shaw, S.C., Blott, S.C., and England, G.C.W. (2019). Behavioural differences in dogs with atopic dermatitis suggest stress could be a significant problem associated with chronic pruritus. Animals, 9.","DOI":"10.3390\/ani9100813"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Wernimont, S.M., Thompson, R.J., Mickelsen, S.L., Smith, S.C., Alvarenga, I.C., and Gross, K.L. (2018). Use of accelerometer activity monitors to detect changes in pruritic behaviors: Interim Clinical data on 6 dogs. Sensors, 18.","DOI":"10.3390\/s18010249"},{"key":"ref_9","first-page":"441-e69","article-title":"Use of activity monitors for assessment of pruritus in an acute model of canine atopic dermatitis","volume":"25","author":"Prost","year":"2014","journal-title":"Vet. Dermatol."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Griffies, J.D., Zutty, J., Sarzen, M., and Soorholtz, S. (2018). Wearable sensor shown to specifically quantify pruritic behaviors in dogs. BMC Vet. Res., 14.","DOI":"10.1186\/s12917-018-1428-x"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Chambers, R.D., Yoder, N.C., Carson, A.B., Junge, C., Allen, D.E., Prescott, L.M., Bradley, S., Wymore, G., Lloyd, K., and Lyle, S. (2021). Deep learning classification of canine behavior using a single collar-mounted accelerometer: Real-world validation. Animals, 11.","DOI":"10.3390\/ani11061549"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"105393","DOI":"10.1016\/j.applanim.2021.105393","article-title":"Dog behaviour classification with movement sensors placed on the harness and the collar","volume":"241","author":"Kumpulainen","year":"2021","journal-title":"Appl. Anim. Behav. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1011","DOI":"10.1109\/JBHI.2017.2710798","article-title":"Detection of nocturnal scratching movements in patients with atopic dermatitis using accelerometers and recurrent neural networks","volume":"22","author":"Moreau","year":"2018","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"eabf9405","DOI":"10.1126\/sciadv.abf9405","article-title":"A skin-conformable wireless sensor to objectively quantify symptoms of pruritus","volume":"7","author":"Chun","year":"2021","journal-title":"Sci. Adv."},{"key":"ref_15","first-page":"80","article-title":"Study on an evaluation of human scratching motions by measuring scratch sounds","volume":"23","author":"Okuyama","year":"2015","journal-title":"J. Jpn. Soc. Appl. Electromagn. Mech."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Muramatsu, S., Hira, E., Momoi, Y., Yamamoto, M., Takamatsu, S., and Itoh, T. (November, January 30). Wearable scratching-sound sensing device for animal healthcare. Proceedings of the 2022 IEEE Sensors, Dallas, TX, USA.","DOI":"10.1109\/SENSORS52175.2022.9967125"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2264","DOI":"10.1007\/s10439-014-1111-8","article-title":"Physiological acoustic sensing based on accelerometers: A survey for mobile healthcare","volume":"42","author":"Hu","year":"2014","journal-title":"Ann. Biomed. Eng."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"014001","DOI":"10.1088\/1361-6439\/ac371e","article-title":"Monitoring of physiological sounds with wearable device based on piezoelectric MEMS acoustic sensor","volume":"32","author":"Qu","year":"2022","journal-title":"J. Micromech. Microeng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"899","DOI":"10.1161\/01.CIR.34.5.899","article-title":"Stethoscope acoustics. II. Transmission and filtration patterns","volume":"34","author":"Ertel","year":"1966","journal-title":"Circulation"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1295","DOI":"10.1121\/1.1903422","article-title":"Speed of sound and transmission loss in silicone rubbers at ultrasonic frequencies","volume":"56","author":"Folds","year":"1974","journal-title":"J. Acoust. Soc. Am."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"302","DOI":"10.1109\/TAP.1966.1138693","article-title":"Numerical solution of initial boundary value problems involving Maxwell\u2019s equations in isotropic media","volume":"14","author":"Yee","year":"1966","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_22","unstructured":"Architectural Institute of Japan (2017). Beginner\u2019s Programming Guide to Numerical Acoustic Simulation, CORONA Publishing Co., Ltd.. [2nd ed.]."},{"key":"ref_23","unstructured":"(2023, April 18). Gasket Design for Optimal Acoustic Performance in MEMS Microphones. Available online: https:\/\/www.st.com\/resource\/en\/application_note\/dm00103201-gasket-design-for-optimal-acoustic-performance-in-mems-microphones-stmicroelectronics.pdf."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1111\/1346-8138.12405","article-title":"Novel acoustic evaluation system for scratching behavior in itching dermatitis: Rapid and accurate analysis for nocturnal scratching of atopic dermatitis patients","volume":"41","author":"Noro","year":"2014","journal-title":"J. Dermatol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1155\/2019\/9294528","article-title":"Design approaches of MEMS microphones for enhanced performance","volume":"2019","author":"Shah","year":"2019","journal-title":"J. Sens."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/9\/4565\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:31:28Z","timestamp":1760124688000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/9\/4565"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,5,8]]},"references-count":25,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2023,5]]}},"alternative-id":["s23094565"],"URL":"https:\/\/doi.org\/10.3390\/s23094565","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,5,8]]}}}