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	Numerical simulation of self-oscillations of human vocal folds based on aeroelastic theory Horáček, Jaromír ; Šidlof, P. Linear two degrees of freedom aeroelastic system for modelling vibrations of human vocal folds was originally developed by which the physiological conditions for so-called phonation thresholds were modelled. The thresholds are given by aeroelastic instabilities of divergence or flutter type. Afterwards the model was generalised taking into account the non-linear aerodynamic terms, important for small glottal openings and large vibration amplitudes. Detailed record
	Numerical simulation of pronunciation of vowels based on FE models of human supraglottal acoustic spaces Krampera, P. ; Horáček, Jaromír ; Dedouch, K. ; Vampola, T. Aproximate finite element models of acoustic spaces corresponding to the human vocal tract for English vowels /a/ and /i/, created according to the geometrical data published in the literature, are used for the numerical simulations. The pronunciation of the vowels /a/ and /i/ is simulated using transient analysis for the FE models. The pulse excitation of the vocal tract is realised by the time dependent displacement of a small circular plate moving at the position of the vocal folds. Detailed record
	Acoustic modal analysis of male vocal tract for Czech vowels Dedouch, K. ; Horáček, Jaromír ; Vampola, T. ; Švec, J. G. ; Kršek, P. ; Havlík, R. Acoustic frequency-modal characteristics of six finite element models of a male vocal tract are presented and analysed. The FE models correspond to the vocal tract geometries for the Czech vowels /a/, /e/, /i/, /o/, /u/ and /y/ were obtained using the magnetic resonance imaging technique. The computed results of the acoustaic modal analysis are in a reasonable agreement with the data on formants known form the Czech phonetic literature. Detailed record
	Modelling of brain tissue influence on wave propagation i human skull after impact loading Pešek, Luděk ; Horáček, Jaromír ; Trnka, Jan ; Veselý, Eduard The contribution deals with the analysis of wawe propagation in human skull filled by a folling which simulates the brain tissue. The results are compared with the original experimental data, which where obtained by the laser- Doppler anemometry and the double pulse holointerferometry. Detailed record
	Numerical simulations of human vocal-fold vibrations in phonation onset caused by aeroelastic instability Horáček, Jaromír ; Šidlof, P. Implementation of nonlinear aerodynamic forces in the aeroelastic model of the vocal folds enabled to simulate the oscillations of the vocal fold just after loosing the stability of the system. Results in time domain are compared with the previous solution in frequency domain. Detailed record
	Natural vibrations and stability of cylindrical shells in interaction with flowing fluid Horáček, Jaromír ; Zolotarev, Igor Natural frequencies and thresholds of stability of thin cylindricaal shell conveying or surrounded by flowing fluid are theoretically studied. Viscous fluid forces are modelled by the Darcy law, and effects of fluid compressibility are discussed. Particularly the effects of fluid viscosity and the type of boundary conditions at the edges of the shell on the critical flow velocities are demonstrated. Detailed record
	Shape of the human vocal folds in a defined phonation position Horáček, Jaromír ; Švec, J. ; Klepáček, I. ; Vetešník, A. ; Veselý, Jan The paper presents experimental investigation of aerodynamic shape of the vocal folds measured in a defined phonation position with excised larynges. The vocal fold vibrations were excited by airflow and monitored acoustically, by means of laser vibrometry, pressure transducers and stroboscopy techniques. Method for casting laryngeal cavities for determining the vocal fold shape was developed. By the optical topography and the electron scanning microscope the shapes of the vocal folds were analysed. Detailed record
	Finite element modeling of male vocal tract considering cleft palate Dedouch, K. ; Horáček, Jaromír ; Vampola, T. ; Černý, L. The FE models of vocal tract designed for vowel /a/ are analyzed considering the cleft palate. The first is designed using the published data, the second model corresponds to the reaal mate vocal tract designed by MRI data. Acoustic modal analysis is focused on investigation of the influence of the cleft palate on the formant frequencies. The results indicate, that after a small jump of the frequencies for a small cleft area the formant frequencies F1, F2 are influenced by the size of the cleft palate only very slightly. Detailed record
	Interaction of viscous incompressible fluid and elastic vocal folds Damašek, Alexandr ; Burda, P. Paper analyses numerical computations of vibrations of vocal folds and their interaction with flowing air using the finite element method. Detailed record
	The contribution to modal analysis of light structures with correction to additional transducer mass Pešek, Luděk ; Veselý, Jan This contribution deals with the correction of measured FRF's to additional mass represented by moving mass of transducer which makes identification of eigencharacteristics more accurate. The correction is aimed at the change of eigenfrequencies by me Detailed record

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