A theoretical study on modelling the respiratory tract with ladder networks by means of intrinsic fractal geometry

• Autor(a) principal: Ionescu, Clara M.
• Data de Publicação: 2010
• Outros Autores: Muntean, Ionut, Machado, J. A. Tenreiro, Keyser, Robin De, Abrudean, Mihail
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/4312
• topic: Fractal structure; Fractional calculus; Frequency domain; Input impedance; Ladder network; Respiratory system

Fractional order modeling of biological systems has received significant interest in the research community. Since the fractal geometry is characterized by a recurrent structure, the self-similar branching arrangement of the airways makes the respiratory system an ideal candidate for the application of fractional calculus theory. To demonstrate the link between the recurrence of the respiratory tree and the appearance of a fractional-order model, we develop an anatomically consistent representation of the respiratory system. This model is capable of simulating the mechanical properties of the lungs and we compare the model output with in vivo measurements of the respiratory input impedance collected in 20 healthy subjects. This paper provides further proof of the underlying fractal geometry of the human lungs, and the consequent appearance of constant-phase behavior in the total respiratory impedance.