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Vol: 53(67) No: 4 / December 2008 

The Use of Non-integer Order Modeling in a Tracheal Simulation Study
Clara Ionescu
Department of Electrical Energy, Systems and Automation, Ghent University, Faculty of Engineering, Technologiepark 913, B9052 Gent-Zwijnaarde, Belgium, phone: (00329) 264-5576, e-mail: clara@autoctrl.UGent.be
Robin De Keyser
Department of Electrical Energy, Systems and Automation, Ghent University, Faculty of Engineering, Technologiepark 913, B9052 Gent-Zwijnaarde, Belgium, e-mail: rdk@autoctrl.UGent.be


Keywords: respiratory impedance, fractional-order model, airway geometry, modeling, simulation, mechanical properties, artificial tissue

Abstract
It is well-known that respiratory disease involves changes in physiological parameters of the human respiratory airways like: tube radius, tube length, thickness or percentage of the cartilage. Fractional-order parametric models can capture spatial changes in mechanical properties of tissue. Such models have not yet been used in clinical practice, but present an interesting alternative to integer-order models. A set of tests denoting changes in airway length and cross-sectional area over the trachea and the bronchi is applied on a respiratory duct simulator. The resulting observations are correlated with morphology. The fractional order model could be further used to gather necessary insight on the required mechanical properties for tracheal replacements and artificial tissue generation.

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