gummfd Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi 1300-1884 1304-4915 Gazi Üniversitesi 10.17341/gazimmfd.1598968 Biomedical Sciences and Technology Biomedical Imaging Electronic Sensors Biyomedikal Bilimler ve Teknolojiler Biyomedikal Görüntüleme Elektronik Algılayıcılar 4-Channel auscultation device with active noise reduction for monitoring, detecting and mapping bowel sound Bağırsak sesinin izlenmesi, tespiti ve haritalanması için aktif gürültü azaltma özelliğine sahip 4 kanallı oskültasyon cihazı https://orcid.org/0000-0003-1626-7618 Güvenç Halil Türk Telekom https://orcid.org/0000-0003-2356-5824 Uluşar Ümit Deniz AKDENİZ ÜNİVERSİTESİ 12 31 2025 40 4 2371 2380 02 06 2025 06 14 2025 Copyright © 1986, Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi 1986 Gazi Üniversitesi Mühendislik Mimarlık Fakültesi Dergisi

Auscultation to and interpreting bowel sounds (BS), an indicator of bowel activity, using simple stethoscopes or microphones is a widely used method for the early, harmless, and practical detection of bowel diseases. The BS obtained through auscultation is analyzed and evaluated using signal processing techniques, yielding medically useful findings. Single-sensor designs, frequently used in recent years, are insufficient for spatial analysis of the bowel, which is spread across the abdominal region. In this study, a design was developed using four sensor microphones and one inverted microphone to perform spatial analysis of bowel activity. In this study, artificial BSs generated from the mathematical equation of the BS were played on an abdominal model using in-ear headphones, inaudible to the outside. After adaptive filtering with the inverted microphone, automatic thresholding based on the noise level, and multi-channel cross-validation, the error rates between the BS location and the reference location determined by phase transformation and stochastic region contraction were calculated. Tests were repeated at sampling frequencies of 10 kHz and 44 kHz. In our study, at a sampling frequency of 44 kHz, although the mean position error is 8.15% higher than in similar studies, its standard deviation is 25.9% lower. Consequently, we observed that BS locations were detected more consistently in our study compared to previous studies.

Bağırsak aktivitesinin bir göstergesi olan bağırsak sesinin (BS) basit stetoskoplar veya mikrofonlarla dinlenmesi ve yorumlanması, bağırsak hastalıklarının erken, zararsız ve pratik tespiti için yaygın kullanılan bir yöntemdir. Dinleme yoluyla elde edilen BS, sinyal işleme teknikleri ile analiz edilerek değerlendirilmekte ve tıbbi olarak yararlı bulgulara ulaşılmaktadır. Son yıllarda sıkça kullanılan tek algılayıcıya sahip tasarımlar, karın bölgesine yayılmış olan bağırsağın konumsal analizi için yeterli olmamaktadır. Bu çalışmada, bağırsak aktivitesinin konumsal analizlerinin yapılabilmesi için 4 algılayıcı mikrofon ve 1 ters mikrofon kullanılarak bir tasarım yapılmıştır. Çalışmada, BS’nin matematiksel denkleminden üretilen yapay BS'ler bir karın bölgesi modeli üzerinde kulak içi kulaklıkla dışardan duyulamayacak biçimde dinletilmiştir. Ters mikrofon ile adaptif filtreleme, gürültü seviyesine göre otomatik eşikleme ve çok kanallı çapraz doğrulama yapıldıktan sonra, faz dönüşümü ile yönlendirilmiş tepki gücü ve stokastik bölge daralması yöntemi ile tespit edilen BS konumu ve referans konum arasındaki hata oranları bulunmuştur. Testler, 10 kHz ve 44 kHz örnekleme frekanslarında tekrarlanmıştır. Çalışmamızda, 44 kHz örnekleme frekansında, ortalama konum hatası benzer çalışmaya oranla %8,15 daha fazla olmasına rağmen, standart sapması %25,9 oranında düşüktür. Sonuç olarak, çalışmamızda BS konumları önceki çalışmalara göre daha tutarlı tespit edildiği görülmüştür.

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