CN1875877A - A method for obtaining subglottic pressure value and calculating phonation efficiency - Google Patents

Abstract

The invention discloses the glottal pressure and computational sounding efficiency and aerodynamics parameter value on the base of aerodynamics modeling technology. The method comprises as follows: providing the method of defining vocal fold three-dimensional geometrical form characteristic value; offering the vocal fold surface three-dimensional reconstruction method; providing the aerodynamics modeling method which is based on three-dimensional finite element algorithm; providing the method of getting glottal pressure and computational sounding efficiency. The method is used to auxiliary diagnose throat, and has significant meaning in sounding function evaluation, sounding physiology, basic research, artistic noise, phonetic science, speech signal processing and linguistic science.

Description

A kind of method that obtains subglottic pressure value and calculate phonation efficiency

Technical field

The invention belongs to the aerodynamic parameter and the sounding characteristic parametric technique field of normal and pathological changes voice, particularly a kind of method that obtains subglottic pressure value and phonation efficiency.

Background technology

Voice are that the mankind exchange the most basic, the most effective, most important means.In the production process of voice, vocal cords are most important phonatory organ, but its simultaneously also is subject to damage and position that pathological changes takes place.Vocal cords present a kind of three-dimensional vibrating of complexity in voiced process, this three-dimensional vibrating pattern shows by the aerodynamic parameter and the sounding acoustic characteristic parameter of voice, in the efficient and the quality that have determined that fundamentally voice produce.Therefore, research and analyse for aerodynamic parameter in the voiced process and sounding acoustic characteristic parameter, not only significant for laryngopathy inspection clinically, larynx functional evaluation, sounding physiology and basic research, and art voice, voice acoustics, voice signal handled and ambit such as linguistics all has far-reaching influence.

In the aerodynamic parameter that voice produce, subglottic pressure value is owing to directly control and influence important parameters such as glottis impedance, glottis intracavity air flow rate, stream condition, glottis upward pressure, stalling point, and becomes a very important aerodynamic parameter in the voice production process.Important parameter in another voice production process is exactly a phonation efficiency, and it is to weigh in the human voiced process aerodynamic energy to the important parameter of voice acoustic energy conversion capability.All about the basic research of vocal cords and actual the use in, and the pathology voice signal carried out in analyzing and processing and the clinical assistant diagnosis, these two parameters all are very basic and important.

At present, adopt two class methods to obtain subglottic pressure value and estimation phonation efficiency both at home and abroad usually.One class is invasive, or even has the method for wound to obtain pressure subglottic.Striding glottis as employing presses the method for conduit and esophageal balloon to carry out invasive measurement pressure subglottic (VandenBerg, 1956), or utilize the spinal anesthesia pin to pass trachea and measure pressure subglottic (Isshiki, 1964), another kind of right and wrong are invasive, as utilize respiratory air flow face shield and the pressure transducer pressure subglottic (Ronthenberg when measuring that the oral cavity is intrinsic pressure estimates pronunciation, 1973), use inverse filtering or areflexia pipe and measure the alternating current-direct current component of air-flow, estimate phonation efficiency and pressure subglottic (Isshiki with their ratio, 1981), with " wave current index " method test pressure subglottic and phonation efficiency (Kakita, 1986).Last class methods are brought many inconvenience owing to be invasive and wound is arranged to tested object, and then class methods then are estimated values, and its accuracy is subjected to the limitation of measuring operation and computational methods.

Summary of the invention

Defective or deficiency at the prior art existence, the objective of the invention is to, based on generation and the aerodynamic Modeling Research acquired achievement thereof of applicant to voice, propose a kind of non-invasively, utilize multiple technologies such as x-ray tomography, oral cavity voice stream pressure signal, Edge extraction, vocal cords surface configuration three-dimensional modeling and dimensional Finite Element method to obtain the accurately method of subglottic pressure value and phonation efficiency.

The present invention takes into account the needs of ambits such as art voice, voice acoustics, voice signal processing and linguistics simultaneously mainly towards laryngopathy inspection, larynx functional evaluation and sounding physiological Study.

In order to realize above-mentioned task, the present invention takes following technical solution:

A kind of method that obtains subglottic pressure value and calculate phonation efficiency is characterized in that, comprises the following steps:

1) at first vocal cords surface three dimension shape facility is defined shape and the parameter that is in various states in the vocal cord movement process with one group of form parameter, Fig. 2 has provided the concrete meaning sketch map of these form parameters;

2) utilize edge of image to detect and extractive technique is carried out rim detection and extraction to the lateral fault and the longitudinal tomography figure of the X line of human body throat, the vocal cords boundary curve that extracts and the parameter in the vocal cord movement process are carried out match, obtain cavity length on minimum glottis diameter, glottis entrance curve radius, glottis exit curve radius, glottis upper surface angle, glottis lower surface angle, glottis inclination angle, glottis length, the glottis, infraglottic cavity length harmony thickness gate parameter;

3) with step 2) every glottis form parameter of being obtained, carrying out vocal cords surface three dimension shape with the described method of step 1) rebuilds, sent out/a by the sounding object: voice pressure signal that records during/sound and air-flow flow value are as boundary condition, adopt the compensation finite element algorithm to carry out the aerodynamic modeling, can obtain subglottic pressure value and other aerodynamic parameter value;

Suppose the air-flow homogenizing, agravic and its flow for permanent, incompressible, then three-dimensional Navier-Stokes equations is expressed as:

$\frac{{\∂v}_x}{\∂t}+v_x\frac{{\∂v}_x}{\∂x}+v_y\frac{{\∂v}_x}{\∂y}+v_z\frac{{\∂v}_x}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂x}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_x}{{\∂x}^2}+\frac{{\∂}^2{v}_x}{{\∂y}^2}+\frac{{\∂}^2{v}_x}{{\∂z}^2}]=0---\left(1\right)$

$\frac{\∂v_y}{\∂t}+v_x\frac{\∂v_y}{\∂x}+v_y\frac{{\∂v}_y}{\∂y}+v_z\frac{{\∂v}_y}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂y}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_y}{\∂x^1}+\frac{{\∂}^2{v}_y}{\∂y^2}+\frac{{\∂}^2{v}_y}{\∂z^2}]=0---\left(2\right)$

$\frac{\∂v_z}{\∂t}+v_x\frac{\∂v_z}{\∂x}+v_y\frac{{\∂v}_z}{\∂y}+v_z\frac{\∂v_z}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂z}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_z}{{\∂x}^2}+\frac{{\∂}^2{v}_z}{\∂y^2}+\frac{{\∂}^2{v}_z}{\∂z^2}]=0---\left(3\right)$

And

$\frac{\∂v_x}{\∂x}+\frac{\∂v_y}{\∂y}+\frac{\∂v_z}{\∂z}=0---\left(4\right)$

V wherein _x, v _y, v _zBe respectively x, the velocity component of y and z direction, ρ is an atmospheric density, and p is an air pressure, and μ is the molecular viscosity coefficient of air;

In the compensation Finite Volume Method, equation of continuity can be expressed as:

$\frac{\∂v_x}{\∂x}+\frac{{\∂v}_y}{\∂y}+\frac{{\∂v}_z}{\∂z}=-\frac{1}{\mathrm{\λ}}p---\left(5\right)$

Wherein λ is an offset value, when offset value is tending towards infinity, satisfies mass conservation law;

The limited bulk equation is by the Galerkin method construct, speed unit uses the shape function of quadravalence to carry out interpolate value and calculates, pressure unit then adopts the linear shape function that defines on the tetrahedron element to come interpolation to replace and calculates, and this pressure interpolating function can produce high-precision quick convergence result; In whole air-flow territory, adopt the speed unit of ten nodes and the pressure unit of four nodes;

Whole limited bulk equation adopts direct iterative method to find the solution, separating of each iteration all uses inferior loose method to proofread and correct to guarantee the stability of iteration, than convergence hour, the iteration of whole limited bulk equation is just finished up to standard error, and standard error is defined as:

$e_i=\underset{j=1,N}{\mathrm{Max}}\left[\right|\frac{a_{i,j}^n-a_{i,j}^{n-1}}{a_{i,\max }^n}\left|\right]---\left(6\right)$

Subscript i (i=v wherein _x, v _y, v _z, perhaps p) and each component of expression fluid variable, n is an iteration progression, α _{I, j}Be illustrated in the nodal value of j i air-flow variable on the node, N represents the sum of node;

4) subglottic pressure that utilizes step 3) and obtained and the oral cavity air flow rate that obtains by breathing mask and the DC component value of oral cavity voice pressure are calculated the acquisition phonation efficiency:

Phonation efficiency calculates by following formula:

$\mathrm{VE}=\frac{P_r}{P_a}=\frac{P_s{A}_m}{P_{\mathrm{sb}}U}---\left(7\right)$

Wherein: P _rBe the radiating acoustic signal power of lip end;

P _aBe air force power under the glottis;

P _sFor measuring the sound pressure signal that mike obtains in the breathing mask;

A _mFor measuring the inner surface area of breathing mask;

P _SbBe average pressure under the glottis;

U is a glottal air flow volume velocity popin average.

The present invention has proposed a kind of non-invasive first, utilize horizontal and vertical x-ray tomography of human body throat and the voice stream pressure signal that is obtained from the human oral cavity face shield, the three-dimensional shape features value defined method of the rim detection of combining image and extraction, vocal cords, the 3D shape reconstruction model of vocal cords and the aerodynamic modeling method of sounding obtain the method for subglottic pressure value, phonation efficiency value and other aerodynamic parameter value.Through detection and computer programming calculation to clinical laryngopathy patient, different laryngopathy patients' subglottic pressure value, phonation efficiency value and other aerodynamic parameter value differ greatly, through contrasting with clinical therapeutic efficacy, method proposed by the invention for one-sided or bilateral vocal cord paralysis, polyp, Wood-scoop shape flesh fix, the auxiliary diagnosis and the treatment of clinical laryngopathy diseases such as webbing, tissue edema, epithelial damage, laryngeal carcinoma all have wide practical use, and provides effective method for the vocal function evaluation simultaneously.

Description of drawings

Fig. 1 is an overall structure block diagram of the present invention.

Fig. 2 is a vocal cords surface shape features parameter-definition method.

Fig. 3 is the example that vocal cords surface three dimension shape is rebuild under one the 10 ° glottis inclination angle conditions.

Fig. 4 gets-40 ° respectively for the glottis angle, and-20 ° ,-10 ° ,-5 °, 0 °, 5 °, 10 °, 20 °, in the time of 40 °, the glottis shape of 9 reconstructions and other parameter.

Below in conjunction with accompanying drawing the embodiment that the inventor provides is described in further detail.

The specific embodiment

Adopt flow chart shown in Figure 1, the step that obtains subglottic pressure value, phonation efficiency value and other aerodynamic parameter value with this method is as follows:

1) definition vocal cords surface three dimension shape facility value

Define the shape that is in various states in the vocal cord movement process with one group of form parameter, for the three-dimensional reconstruction of vocal cords shape lays the first stone.

Fig. 2 has provided the concrete meaning sketch map of these form parameters, and these form parameters comprise:

1. minimum glottis diameter.Refer to glottis intracavity the glottis distance values at narrow place, i.e. D among Fig. 2 _MinShown length.

2. glottis entrance curve radius.The radius of curvature that refers to glottis porch camber line, i.e. R among Fig. 2 _InShown radius.

3. glottis exit curve radius.The radius of curvature that refers to glottis exit camber line, i.e. R among Fig. 2 _OutShown radius.

4. glottis upper surface angle.Refer to the angle between glottis upper surface tangent slope and the horizontal line, i.e. θ among Fig. 2 _SupShown angle.

5. glottis lower surface angle.Refer to the angle between glottis lower surface tangent slope and the horizontal line, i.e. θ among Fig. 2 _SubShown angle.

6. glottis inclination angle.The angle that refers to two a certain instantaneous moments in surface of vocal cords, i.e. length shown in the T among Fig. 2.

7. glottis length.Refer to the collinear length between vocal cords entrance curve and the exit curve, i.e. length shown in the T among Fig. 2.

8. glottis thickness.Refer to the length between vocal cords upper edge and the lower edge.

9. cavity length on the glottis.The length of sound channel on the finger, i.e. Q among Fig. 2 ₁Shown length.

10. infraglottic cavity length.Refer to the length of sound channel, i.e. Q among Fig. 2 down ₂Shown length.

2) vocal cords surface three dimension shape is rebuild

Utilize edge of image to detect and extractive technique laterally reaches longitudinal tomography figure to the X line of human body throat and carries out rim detection and extraction, the vocal cords boundary curve and the described form parameter of step 1) that extract are carried out match, thereby rebuild the 3D shape on vocal cords surface.

Rebuilding vocal cords surface three dimension shape adopts following steps to get final product:

(1) obtain object of study throat laterally with x-ray tomography, the oral cavity air flow rate signal and the oral cavity voice pressure signal of synchronous acquisition object of study simultaneously longitudinally.

Under doctor's assistance, send out vowel/a in object of study with breast sound area tune :/time, obtain object of study throat laterally with x-ray tomography longitudinally, generally should gather at least ten tension fault figure respectively to obtain glottis form parameter comparatively accurately, utilize the oral cavity air flow rate signal and the oral cavity voice pressure signal of oral mask synchronous acquisition object of study simultaneously.

(2) the lateral fault figure of the frame frame throat image to obtaining utilizes S-Shaped Algorithm (Karim, 1998) to detect the vocal cords boundary curve.

(3) the vocal cords lateral surfaces boundary curve and the glottis form parameter that will adopt step (1) to be obtained carried out match, obtains following parameter: 1. minimum glottis diameter; 2. glottis entrance curve radius; 3. glottis exit curve radius; 4. glottis upper surface angle; 5. glottis lower surface angle; 6. glottis inclination angle; 7. glottis length; 8. cavity length on the glottis; 9. infraglottic cavity length;

(4) the longitudinal tomography figure of the frame frame throat image to obtaining utilizes S-Shaped Algorithm (Karim, 1998) to detect the vocal cords boundary curve.

(5) the vertical surperficial boundary curve of vocal cords and the glottis form parameter that obtain are carried out match, obtain the thickness parameter of vocal cords.

(6) utilize the glottis form parameter of acquisition and the three-dimensional shape features value defined method of vocal cords, vocal cords surface three dimension shape is rebuild.

3) the glottis angular dimensions in the vocal cords surface three dimension shape of being rebuild is changed, get-40 ° respectively ,-20 ° ,-10 ° ,-5 °, 0 °, 5 °, 10 °, 20 °, 40 °, other parameter constant obtains the glottis shape of 9 reconstructions.Fig. 4 has provided these 9 shape and other parameters of rebuilding vocal cords, and hypothesis glottis shape is symmetrical fully in research process, has therefore only provided the form parameter of half.

4) DC component with oral cavity air flow rate and oral cavity voice pressure signal is a boundary condition, utilizes the three-dimensional finite element modeling method of sounding, calculates subglottic pressure value respectively for 9 vocal cords surface three dimension shapes of rebuilding, and other aerodynamic parameter value.What obtain after each parameter value that calculates gained is averaged is exactly the parameter value of wishing acquisition.

The calculating of subglottic pressure value is based on three-dimensional finite element algorithm, and its method is:

Because Reynolds number lower (generally being not more than 2000) in the human voiced process, therefore can think the air-flow homogenizing, agravic and its flow for permanent, incompressible, then three-dimensional Navier-Stokes equations can be expressed as:

$\frac{\∂v_x}{\∂t}+v_x\frac{\∂v_x}{\∂x}+v_y\frac{\∂v_x}{\∂y}+v_z\frac{\∂v_x}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂x}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_x}{{\∂x}^2}+\frac{{\∂}^2{v}_x}{\∂y^2}+\frac{{\∂}^2{v}_x}{\∂z^2}]=0---\left(1\right)$

$\frac{\∂v_y}{\∂t}+v_x\frac{\∂v_y}{\∂x}+v_y\frac{{\∂v}_y}{\∂y}+v_z\frac{\∂v_y}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂y}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_y}{{\∂x}^2}+\frac{{\∂}^2{v}_y}{\∂y^2}+\frac{{\∂}^2{v}_y}{\∂z^2}]=0---\left(2\right)$

$\frac{\∂v_z}{\∂t}+v_x\frac{\∂v_z}{\∂x}+v_y\frac{{\∂v}_z}{\∂y}+v_z\frac{{\∂v}_z}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂z}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_z}{{\∂x}^2}+\frac{{\∂}^2{v}_z}{\∂y^2}+\frac{{\∂}^2{v}_z}{{\∂z}^2}]=0---\left(3\right)$

And

$\frac{\∂v_x}{\∂x}+\frac{\∂v_y}{\∂y}+\frac{{\∂v}_z}{\∂z}=0---\left(4\right)$

V wherein _x, v _y, v _zBe respectively x, the velocity component of y and z direction,, ρ is an atmospheric density, and p is an air pressure, and μ is the molecular viscosity coefficient of air.

In the compensation Finite Volume Method, equation of continuity (4) can be expressed as:

$\frac{\∂v_x}{\∂x}+\frac{{\∂v}_y}{\∂y}+\frac{\∂v_z}{\∂z}=-\frac{1}{\mathrm{\λ}}p---\left(5\right)$

Wherein λ is an offset value.When offset value is tending towards infinity, satisfy mass conservation law.

The limited bulk equation is by the Galerkin method construct.Speed unit uses the shape function of quadravalence to carry out interpolate value and calculates, and pressure unit then adopts the linear shape function that defines on the tetrahedron element to come interpolation to replace and calculates, and this pressure interpolating function can produce high-precision quick convergence result.In whole air-flow territory, we have adopted the speed unit of ten nodes and the pressure unit of four nodes.

Whole limited bulk equation adopts direct iterative method to find the solution.Separating of each iteration all uses inferior loose method to proofread and correct to guarantee the stability of iteration.Than convergence hour, the iteration of whole limited bulk equation is just finished up to standard error.Standard error is defined as:

$e_i=\underset{j=1,N}{\mathrm{Max}}\left[\right|\frac{a_{i,j}^n-a_{i,j}^{n-1}}{a_{i,\max }^n}\left|\right]---\left(6\right)$

Subscript i (i=v wherein _x, v _y, v _z, perhaps p) and each component of expression fluid variable, n is an iteration progression, α _{I, j}Be illustrated in the nodal value of j i air-flow variable on the node, N represents the sum of node.

5) utilize oral cavity air flow rate and the DC component of oral cavity voice pressure signal and the subglottic pressure value that obtains that obtains, calculate phonation efficiency by following formula:

$\mathrm{VE}=\frac{P_r}{P_a}=\frac{P_s{A}_m}{P_{\mathrm{sb}}U}---\left(7\right)$

Wherein: P _rBe the radiating acoustic signal power of lip end;

P _aBe air force power under the glottis;

P _sFor measuring the sound pressure signal that mike obtains in the breathing mask;

A _mFor measuring the inner surface area of breathing mask;

P _SbBe average pressure under the glottis;

U is a glottal air flow volume velocity popin average;

6) utilize other aerodynamic parameter value that obtains to carry out the analysis of sounding acoustic characteristic.

Adopt this method, except calculating subglottic pressure value, can also calculate following other aerodynamic parameter value, mainly contain:

1. glottis impedance is compared with corresponding air flow stream value and is obtained by striding glottis pressure;

2. stride glottis pressure, subtract each other by subglottic pressure value and glottis upward pressure value and obtain;

3. the pressure minimum is obtained by glottis cavity pressure distribution field value;

4. speed maximum is obtained by glottis intracavity velocity distribution pattern value;

5. stalling point is obtained by glottis cavity pressure distribution field;

6. go up vocal cords surface pressing and following vocal cords surface pressing ratio, obtain by glottis cavity pressure distribution field value;

7. pressure utmost point low value with stride the ratio that glottis is pressed, by the pressure minimum with stride glottis pressure value and compare and obtain;

8. press ratio on the glottis with pressure subglottic; Compare with the pressure subglottic value by pressure value on the glottis and to obtain.

The acoustic characteristic of sounding mainly comprises parameters such as the sound intensity, fundamental frequency and tone, exists close, very important relation between the air force mathematic(al) parameter of sounding and sounding parameter.Utilize the acoustic characteristic of all right qualitative analysis sounding of achievement in research of the present invention, mainly comprise:

The increase of 1. striding the glottis pressure can make intensity of phonation increase;

The increase of 2. striding the glottis pressure can make the sounding fundamental frequency increase simultaneously;

3. stride increase that glottis the presses tone can make sounding simultaneously the time and uprise, this is because vocal cords need the higher glottis of striding press the vibration of keeping same amplitude;

4. the increase of glottis impedance can reduce the sound intensity of sounding;

Make the following instructions for the method applied in the present invention, technological means and interpretation of result in addition:

The present invention narrate obtain object of study throat laterally and what mainly propose during the means of longitudinal tomography figure is to utilize x-ray tomography imaging technique (CT), but the scope of application of the present invention is not limited thereto, the present invention is for nuclear magnetic resonance (MRI), energy focusing ultrasonic-high (HIFU) imaging, positron emission tomography (PET) waits other tomograph imaging method that higher adaptability is also arranged.

2. S-Shaped Algorithm (snake) (Karim has been proposed when the present invention narrates edge of image detection and extractive technique, 1998), mainly be because this method has dynamic flexible, characteristics that amount of calculation is little, but be not limited to this method for edge of image detection and extraction, other numerous effective Image Edge-Detection and extracting method also all are applicable to the present invention.

3. the result of the method for the invention also is not limited to obtain subglottic pressure value, phonation efficiency value and other aerodynamic parameter value, as above-mentioned steps 6) described, sounding air force mathematic(al) parameter and sounding acoustic characteristic have substantial connection, will disclose the achievement of more object of study sounding characteristic aspect to the further investigation that concerns between them.

The present invention not only has real directive significance for clinical laryngopathy inspection, larynx functional evaluation, and to sounding physiology and basic research, and ambits such as art voice, voice acoustics, voice signal processing and linguistics are all significant.The more important thing is, it is further for research, analysis, the modeling of the mechanism of speech production under throat's pathological state, and the collection of pathological signals, analysis, classification, processing, especially because changing caused voice distortion research, the glottis geometry laid good basis, it to the development of voice rehabilitation, phonetic synthesis, speech processes, speech recognition, all has far-reaching influence simultaneously.

Below be the embodiment that the inventor provides, but be not limited to these embodiment.

Embodiment 1: the male is subglottic pressure value and phonation efficiency preparation method during sounding softly normally

The object of study of embodiment is a young man of 25 years old, adopts following steps to obtain subglottic pressure, phonation efficiency value and other aerodynamic parameter value:

1) under doctor's assistance, send out vowel/a in object of study softly with breast sound area tune :/time, gather respectively ten object of study throats laterally with x-ray tomography longitudinally, utilize the oral cavity air flow rate signal and the oral cavity voice pressure signal of oral mask synchronous acquisition object of study simultaneously, the oral cavity air flow rate that is collected is 189.4cm ³/ s, oral cavity voice pressure is 0.51Pa.

2) the horizontal and longitudinal tomography figure image to the throat that obtains utilizes S-Shaped Algorithm (Karim, 1998) to detect the vocal cords boundary curve.

3) vocal cords that obtain are laterally carried out match with vertical surperficial boundary curve and glottis form parameter, comprehensive ten faultage images obtain following parameter value: 1. average minimum glottis diameter=0.06cm; 2. glottis entrance curve radius=0.15cm; 3. glottis exit curve radius=0.0987cm; 4. glottis upper surface angle=0 °; 5. glottis lower surface angle=40 °; 6. glottis inclination angle=10 °; 7. glottis length=0.3cm; 8. cavity length=0.6cm on the glottis; 9. infraglottic cavity length=1.5cm; 10. glottis thickness=1.2cm.

4) utilize the glottis form parameter of acquisition and the three-dimensional shape features value defined method of vocal cords, vocal cords surface three dimension shape is rebuild.When Fig. 3 showed the glottis angle and is 10 °, the 3D shape of vocal cords was rebuild figure.

5) the glottis angular dimensions in the vocal cords surface three dimension shape of being rebuild is changed, get-40 ° respectively ,-20 ° ,-10 ° ,-5 °, 0 °, 5 °, 10 °, 20 °, 40 °, other parameter constant obtains the glottis shape of 9 reconstructions.Fig. 4 shows these 9 shape and other parameters of rebuilding vocal cords, supposes glottis shape symmetry fully, has therefore only provided the form parameter of half.

6) the oral cavity air flow rate (189.4cm that obtains with step 1) ³/ s) and and glottis rebuild and to be shaped as boundary condition, establishing the model outlet pressure is zero, utilizes claim 1 the 3rd) the three-dimensional finite element modeling method of described sounding of step, calculate subglottic pressure value respectively for 9 vocal cords surface three dimension shapes that step 5) is rebuild, 9 subglottic pressure values that obtain are followed successively by: 7.86,7.87,8.21,8.53,9.81,7.49,6.93,7.55,7.68cmH ₂O, its average 7.99cmH ₂O is the subglottic pressure value of being asked.

7) utilize the oral cavity air flow rate of step 1) acquisition and the subglottic pressure value of oral cavity voice pressure signal and step 6) acquisition, utilize the formula (7) in the claim 1 to calculate phonation efficiency.Wherein, the sound pressure signal that mike obtains in the breathing mask is 0.51Pa, and throughput is 189.4cm ³/ s, the inner surface area of breathing mask are 100cm ³, average pressure obtains being 7.99cmH by step 6) under the glottis ₂O, by formula can this male softly the phonation efficiency during sounding be 3.37*10 ^-4

8) utilize subglottic pressure value and the stream pressure velocity field that obtains,, calculate other value of consult volume in conjunction with the described method of claim 2.In this example: 1. the glottis resistance value is 4.22gcm ^-4s ^-12. striding glottis pressure is 7.99cmH ₂O; 3. the pressure minimum is-866.08Pa; 4. speed maximum is 7.097m/s; 5. stalling point is at 0.08cm place, minimum glottis diameter downstream; 6. going up the vocal cords surface pressing is 1 (because vocal cords and pressure distribution thereof are symmetrical fully) with following vocal cords surface pressing ratio; 7. pressure utmost point low value is 1.08 with the ratio of striding the glottis pressure; 8. pressing ratio with pressure subglottic to be made as under the atmospheric situation at outlet pressure on the glottis is zero.

Embodiment 2: subglottic pressure value and phonation efficiency preparation method during the normal loud sounding of male

Adopt object of study and the research step identical with embodiment 1, send out vowel/a in this object of study loudly with breast sound area tune: in/time, the oral cavity air flow rate that is collected is 502.8cm ³/ s, oral cavity voice pressure is 2.6Pa.X-ray tomography during again to its sounding is analyzed, the parameter value that extracts is identical during with sounding softly, so the 3D shape figure of vocal cords is identical, the glottis angular dimensions is carried out calculating 9 subglottic pressure values after the variation identical with embodiment 1 be followed successively by: 56.62,48.22,45.55,44.94,43.9,43.01,42.55,43.38,44.18cmH ₂O, its average 45.87cmH ₂O is the subglottic pressure value of being asked.Phonation efficiency when employing can calculate the loud sounding of this male with quadrat method is 1.127*10 ^-4Utilize subglottic pressure value and the stream pressure velocity field that obtains again, it is as follows to obtain other value of consult volume: 1. the glottis resistance value is 9.12gcm ^-4s ^-12. striding glottis pressure is 45.87cmH ₂O; 3. the pressure minimum is-52.12cmH ₂O; 4. speed maximum is 15.3m/s; 5. stalling point is at 0.10cm place, minimum glottis diameter downstream; 6. going up the vocal cords surface pressing is 1 (because vocal cords and pressure distribution thereof are symmetrical fully) with following vocal cords surface pressing ratio; 7. pressure utmost point low value is 1.14 with the ratio of striding the glottis pressure; 8. pressing ratio with pressure subglottic to be made as under the atmospheric situation at outlet pressure on the glottis is zero.

Claims (2)

1. a method that obtains subglottic pressure value and calculate phonation efficiency is characterized in that, comprises the following steps:

1) at first vocal cords surface three dimension shape facility is defined shape and the parameter that is in various states in the vocal cord movement process with one group of form parameter;

2) utilize edge of image to detect and extractive technique is carried out rim detection and extraction to the lateral fault and the longitudinal tomography figure of the X line of human body throat, the vocal cords boundary curve that extracts and the parameter in the vocal cord movement process are carried out match, obtain cavity length on minimum glottis diameter, glottis entrance curve radius, glottis exit curve radius, glottis upper surface angle, glottis lower surface angle, glottis inclination angle, glottis length, the glottis, infraglottic cavity length harmony thickness gate parameter;

3) with step 2) every glottis form parameter of being obtained, carrying out vocal cords surface three dimension shape with the described method of step 1) rebuilds, sent out/a by the sounding object: voice pressure signal that records during/sound and air-flow flow value are as boundary condition, adopt the compensation finite element algorithm to carry out the aerodynamic modeling, can obtain out subglottic pressure value and other aerodynamic parameter value;

Suppose the air-flow homogenizing, agravic and its flow for permanent, incompressible, then three-dimensional Navier-Stokes equations is expressed as:

$\frac{{\∂v}_x}{\∂t}+v_x\frac{\∂v_x}{\∂x}+v_y\frac{{\∂v}_x}{\∂y}+v_z\frac{\∂v_x}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂x}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_x}{{\∂x}^2}+\frac{{\∂}^2{v}_x}{\∂y^2}+\frac{{\∂}^2{v}_x}{{\∂z}^2}]=0...\left(1\right)$

$\frac{{\∂v}_y}{\∂t}+v_x\frac{\∂v_y}{\∂x}+v_y\frac{{\∂v}_y}{\∂y}+v_z\frac{\∂v_y}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂y}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_y}{{\∂x}^2}+\frac{{\∂}^2{v}_y}{\∂y^2}+\frac{{\∂}^2{v}_y}{{\∂z}^2}]=0...\left(2\right)$

$\frac{{\∂v}_z}{\∂t}+v_x\frac{\∂v_z}{\∂x}+v_y\frac{{\∂v}_z}{\∂y}+v_z\frac{\∂v_z}{\∂z}+\frac{1}{\mathrm{\ρ}}\frac{\∂p}{\∂z}-\frac{\mathrm{\μ}}{\mathrm{\ρ}}[\frac{{\∂}^2{v}_z}{{\∂x}^2}+\frac{{\∂}^2{v}_z}{\∂y^2}+\frac{{\∂}^2{v}_z}{{\∂z}^2}]=0...\left(3\right)$

And

$\frac{{\∂v}_x}{\∂x}+\frac{\∂v_y}{\∂y}+\frac{{\∂v}_z}{\∂z}=0...\left(4\right)$

V wherein _x, v _v, v _zBe respectively x, the velocity component of y and z direction, ρ is an atmospheric density, and p is an air pressure, and μ is the molecular viscosity coefficient of air;

In the compensation Finite Volume Method, equation of continuity can be expressed as:

$\frac{{\∂v}_x}{\∂x}+\frac{\∂v_y}{\∂y}+\frac{\∂v_z}{\∂z}=-\frac{1}{\mathrm{\λ}}p...\left(5\right)$

Wherein λ is an offset value, when offset value is tending towards infinity, satisfies mass conservation law;

The limited bulk equation is by the Galerkin method construct, speed unit uses the shape function of quadravalence to carry out interpolate value and calculates, pressure unit then adopts the linear shape function that defines on the tetrahedron element to come interpolation to replace and calculates, and this pressure interpolating function can produce high-precision quick convergence result; In whole air-flow territory, adopt the speed unit of ten nodes and the pressure unit of four nodes;

Whole limited bulk equation adopts direct iterative method to find the solution, separating of each iteration all uses inferior loose method to proofread and correct to guarantee the stability of iteration, than convergence hour, the iteration of whole limited bulk equation is just finished up to standard error, and standard error is defined as:

$e_i=\underset{j=1,N}{\mathrm{Max}}\left[\right|\frac{a_{i,j}^n-a_{i,j}^{n-1}}{a_{i,\max }^n}\left|\right]...\left(6\right)$

Subscript i=v wherein _x, v _y, v _zPerhaps p, each component of expression fluid variable, n is an iteration progression, a _{I, j}Be illustrated in the nodal value of j i air-flow variable on the node, N represents the sum of node;

4) subglottic pressure that utilizes step 3) and obtained and the oral cavity air flow rate that obtains by breathing mask and the DC component value of oral cavity voice pressure are calculated the acquisition phonation efficiency:

Phonation efficiency calculates by following formula:

$\mathrm{VE}=\frac{P_r}{P_a}=\frac{P_s{A}_m}{P_{\mathrm{sb}}U}...\left(7\right)$

Wherein: P _rBe the radiating acoustic signal power of lip end;

P _aBe air force power under the glottis;

P _sFor measuring the sound pressure signal that mike obtains in the breathing mask;

A _mFor measuring the inner surface area of breathing mask;

P _SbBe average pressure under the glottis;

U is a glottal air flow volume velocity popin average.

2. the method for claim 1 is characterized in that, described other aerodynamic parameter value mainly contains:

1. glottis impedance is compared with corresponding air flow stream value and is obtained by striding glottis pressure;

2. stride glottis pressure, subtract each other by subglottic pressure value and glottis upward pressure value and obtain;

3. the pressure minimum is obtained by glottis cavity pressure distribution field value;

4. speed maximum is obtained by glottis intracavity velocity distribution pattern value;

5. stalling point is obtained by glottis cavity pressure distribution field;

6. go up vocal cords surface pressing and following vocal cords surface pressing ratio, obtain by glottis cavity pressure distribution field value;

7. pressure utmost point low value with stride the ratio that glottis is pressed, by the pressure minimum with stride glottis pressure value and compare and obtain;

8. press ratio on the glottis with pressure subglottic; Compare with the pressure subglottic value by pressure value on the glottis and to obtain.