Input acoustic-impedance measurement of the subglottal system

Ishizaka, K.; Matsudaira, M.; Kaneko, Tadaaki

doi:10.1121/1.381064

Cited by 85 publications

(71 citation statements)

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“…In general, two-mass models predict . This area waveform is slightly skewed with respect to the sinusoidal waveform A g (t) of expression (7).…”

Section: Resultsmentioning

confidence: 99%

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A water hammer analysis of pressure and flow in the voice production system

Sciamarella

Artana

2009

Speech Communication

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“…In general, two-mass models predict . This area waveform is slightly skewed with respect to the sinusoidal waveform A g (t) of expression (7).…”

Section: Resultsmentioning

confidence: 99%

“…Ishizaka was probably the first to advocate in 1976 the application of the water hammer theory to the phonatory system, when discussing the input acoustic impedance looking into the trachea [7]. More recently, the water hammer theory was invoked in the context of tracheal wall motion detection [8].…”

Section: Introductionmentioning

confidence: 99%

A water hammer analysis of pressure and flow in the voice production system

Sciamarella

Artana

2009

Speech Communication

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“…Input impedance is not usually measured in this direct manner with brief volume velocity pulses, but indirectly with known impedances in series with the system (e.g., Ishizaka et al, 1976). A similar expression holds for sub-glottal input impedance,Ẑ sub ,…”

Section: Input Impedances and Relations To Green's Function Segmentsmentioning

confidence: 99%

“…This boundary condition will account for the source of B from the lungs. Here, the conception of the bronchial tree with an upper conductive region and lower transitional and respiratory region is adopted, as in Ishizaka et al (1976). The surface S L is supposed to be somewhere in the conductive region.…”

Section: A Preliminariesmentioning

confidence: 99%

Source-tract interaction with prescribed vocal fold motion

McGowan¹,

Howe

2012

The Journal of the Acoustical Society of America

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An equation describing the time-evolution of glottal volume velocity with specified vocal fold motion is derived when the sub- and supra-glottal vocal tracts are present. The derivation of this Fant equation employs a property explicated in Howe and McGowan [(2011) J. Fluid Mech. 672, 428–450] that the Fant equation is the adjoint to the equation characterizing the matching conditions of sub- and supra-glottal Green’s functions segments with the glottal segment. The present aeroacoustic development shows that measurable quantities such as input impedances at the glottis, provide the coefficients for the Fant equation when source-tract interaction is included in the development. Explicit expressions for the Green’s function are not required. With the poles and zeros of the input impedance functions specified, the Fant equation can be solved. After the general derivation of the Fant equation, the specific cases where plane wave acoustic propagation is described either by a Sturm-Liouville problem or concatenated cylindrical tubes is considered. Simulations show the expected skewing of the glottal volume velocity pulses depending on whether the fundamental frequency is below or above a sub- or supra-glottal formant. More complex glottal wave forms result when both the first supra-glottal fundamental frequencies are high and close to the first sub-glottal formant.

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“…Therefore for the purpose of illustration the three subglottal formants F s 1, F s 2, F s 3 and their corresponding half-power bandwidths Df are taken to be defined as in Table II (Ishizaka et al, 1976;Zanartu et al, 2007;Howe and McGowan, 2012).…”

Section: A Model Vocal Tract Parametersmentioning

confidence: 99%

Voicing produced by a constant velocity lung source

Howe

McGowan²

2013

The Journal of the Acoustical Society of America

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An investigation is made of the influence of subglottal boundary conditions on the prediction of voiced sounds. It is generally assumed in mathematical models of voicing that vibrations of the vocal folds are maintained by a constant subglottal mean pressure p I , whereas voicing is actually initiated by contraction of the chest cavity until the subglottal pressure becomes large enough to separate the vocal folds. The problem is reformulated to determine voicing characteristics in terms of a prescribed volumetric flow rate Q o of air from the lungs-the evolution of the resulting time-dependent subglottal mean pressure p ðtÞ is then governed by glottal mechanics, the aeroacoustics of the vocal tract, and the influence of continued contraction of the lungs. The new problem is analyzed in detail for an idealized mechanical vocal system that permits precise specification of all boundary conditions. Predictions of the glottal volume velocity pulse shape are found to be in good general agreement with the traditional constant-p I theory when p I is set equal to the time averaged value of p ðtÞ. But, in all cases examined the constant-p I approximation yields values of the mean flow rates Q o and sound pressure levels that are smaller by as much as 10%.

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Input acoustic-impedance measurement of the subglottal system

Cited by 85 publications

References 0 publications

A water hammer analysis of pressure and flow in the voice production system

A water hammer analysis of pressure and flow in the voice production system

Source-tract interaction with prescribed vocal fold motion

Voicing produced by a constant velocity lung source

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