年間 6 号発行
ISSN 印刷: 2152-5102
ISSN オンライン: 2152-5110
Indexed in
Features of the "Tissue" Sound Propagation Channel in Human Thorax
要約
The acoustic propagation through biological tissues of a thorax with allowance for availability of its costal framework and the surface soft tissues is investigated. Estimations of the density, the sound speed and the attenuation coefficient in the lung parenchyma and the soft biotissues are obtained. Within the approach of linear acoustics the mathematical model is developed permitting to assess quantitatively a performance of the sound transmission from the lung to the surface of the human body. It is shown that at propagation of the sound in the considered system the piston mode dominates. It is shown that when the breath sounds propagate in the thorax, the effect of its costal grating is exhibited by the constant additional loss of the signal. It is shown that the low-frequency domains of the spectrum of normal respiratory sounds are formed by the sources disposed on whole volume of the lung. The high-frequency spectrum is formed predominantly by the sources disposed on the lung's peripherals.