Hudde H, Slatky H
Lehrstuhl für Allgemeine Elektrotechnik und Akustik, Ruhr-Universität Bochum, Federal Republic of Germany.
J Acoust Soc Am. 1989 Aug;86(2):475-92. doi: 10.1121/1.398227.
The input impedance at primary bronchi of excised human lungs was measured in the frequency range from 2-5000 Hz. For the measurements, a self-developed acoustic impedance head and a narrow-band measuring system with sinusoidal excitation were used. The lungs were inflated and deflated by using an arrangement called respiratory state controller. The impedances were thus measured at different states of lung inflation. An already existing mathematical model was developed further to cover not only fairly inflated lungs, but also deflated ones. The parameter sensitivity of this model is investigated. The acoustomechanical parameters of the model were fitted to match the impedances measured. It turns out that some of these parameters are hardly calculable. The values given in this paper were chosen to agree with the measurements and to be physically reasonable. Although the measurements were performed at primary bronchi, the model is able to predict also impedances at the top end of the trachea (at different respiratory states). This impedance is useful for speech signal processing applications. The model prediction of the trachea impedances agrees well with previous results of other authors.
在2 - 5000赫兹的频率范围内测量了切除的人肺主支气管处的输入阻抗。测量时，使用了自行研制的声阻抗探头和带有正弦激励的窄带测量系统。通过一种称为呼吸状态控制器的装置对肺进行充气和放气。从而在肺充气的不同状态下测量阻抗。对一个已有的数学模型进行了进一步开发，使其不仅能涵盖充气适度的肺，还能涵盖放气的肺。研究了该模型的参数敏感性。对模型的声力学参数进行拟合以匹配测量得到的阻抗。结果发现其中一些参数几乎无法计算。本文给出的值是为了与测量结果相符且在物理上合理而选取的。尽管测量是在主支气管处进行的，但该模型也能够预测气管顶端（在不同呼吸状态下）的阻抗。这种阻抗在语音信号处理应用中很有用。气管阻抗的模型预测与其他作者先前的结果吻合良好。
