ACOUSTIC COUPLING IN PHONATION AND ITS EFFECT ON ...

More documents

Recommendations

Info

xviABBREVIATI<strong>ON</strong>SAC Alternating current, unsteady component of a signalACC Neck surface acceleration signalAP Anterior-posterior axis of the vocal foldsBLEAP Boundary layer estimation of asymmetric pressuresBMI Body Mass IndexCPIF Closed phase inverse filteringdB DecibelDC Direct current, steady component of a signalEGG Electroglottograph signalHRF Harmonic richness factorHSV Laryngeal high-speed videoendoscopyIBIF Impedance-based inverse filteringIF72 Bibliographic reference: Ishizaka and Flanagan (1972)IOP Intraoral pressure signalLPC Linear predictive codingLR Left and right vocal foldsMADR Maximum area declination rateMFDR Maximum flow declination rateMIC Microphone signalMRI Magnetic resonance imagingRMSE Root mean squared errorSPL Sound pressure levelST95 Bibliographic reference: Story and Titze (1995)OVV Oral airflow signal
xviiABSTRACTZañartu Salas, M. Ph.D., Purdue University, August 2010. Acoustic Coupling inPhonation and its Effect on Inverse Filtering of Oral Airflow and Neck Surface Acceleration.Major Professor: George R. Wodicka.Many aspects of the coupling between vocal fold motion, glottal airflow, andresulting sound waves remain unexplored, particularly during incomplete glottal closure.In addition, this coupling has been associated with distortions in the estimatesof glottal parameters obtained from neck acceleration measurements, thus affectingthe ambulatory assessment of vocal function. This acoustic coupling and its effectson inverse filtering of oral airflow and neck surface acceleration during vowel productionwere investigated using numerical and experimental methods. A lumpedelement self-oscillating model was extended to include different types of incompleteglottal closure, which provided an enhanced simulation tool that mimicked normaland hyperfunctional voices. Novel in vivo measurements and analyses of vocal foldtissue instabilities due to acoustic coupling were obtained using synchronous laryngealhigh-speed videoendoscopy recordings. These observations suggested that instabilitiesdiffered at the vocal fold tissue level from those where no strong coupling waspresent, but classified each as subcritical Hopf bifurcations. These findings supportedthe concept of describing interactions within the voice production system based onacoustic impedance representations. In addition, an impedance-based inverse filteringapproach with time-varying glottal coupling demonstrated how source-tract interactionsskewed and altered the glottal pulses. Based on these observations, a subglottalinverse filtering scheme for neck surface acceleration was proposed and evaluated,yielding estimates of glottal aerodynamic parameters with accuracy comparable tothat of standard pneumotachograph measurements and closed-phase inverse filtering.
Page 2 and 3: iiACKNOWLEDGMENTSI am truly gratefu
Page 4 and 5: ivPage2.5.1 Traditional objective a
Page 6 and 7: viPage6.3.1 Evaluation of uncoupled
Page 8 and 9: viiiTablePage4.3 HSV measures taken
Page 10 and 11: xFigurePage4.4 Downward pitch glide
Page 12 and 13: xiiFigurePage5.12 Application of ai
Page 14 and 15: xivFigurePage6.26 Uncoupled glottal
Page 18 and 19: 11. INTRODUCTIONThis chapter introd
Page 20 and 21: 3methods incorrectly suppress rippl
Page 22 and 23: 5this hypothesis would validate cur
Page 24 and 25: 72. BACKGROUNDThe increasing intere
Page 26 and 27: 9flow in the vocal tract in time do
Page 28 and 29: 112.1.2 The glottal impedanceThe gl
Page 30 and 31: 13with previous considerations on t
Page 32 and 33: 152.1.4 Self-oscillating models of
Page 34 and 35: 17few high-order models are known t
Page 36 and 37: 19known as non-modal phonation. Non
Page 38 and 39: 212.3 Bifurcations in voice product
Page 40 and 41: 23Numerical models have also served
Page 42 and 43: 25an all-pole system, this instabil
Page 44 and 45: 27data points to obtain an acceptab
Page 46 and 47: 29High-speed video is expected to s
Page 48 and 49: 31recordings of normal vocal activi
Page 50 and 51: 33ject’s radiated voice in the ro
Page 52 and 53: 35simply increasing the body stiffn
Page 54 and 55: 37quently proposed [74,97]. However
Page 56 and 57: 39was used, where the index α indi
Page 58 and 59: 41P kd = (P s + p s − p o )/(1
Page 60 and 61: 43Table 3.1Material properties used
Page 62 and 63: 451.5Glottis10.5Radius (cm)0Subglot
Page 64 and 65: 471500Glottal airflowUoUg1500Glotta
Page 66 and 67:
49a different origin. In all cases,
Page 68 and 69:
51Data from recordings on human sub
Page 70 and 71:
530.04Driving forces0.05Driving for
Page 72 and 73:
55500400Intraglottal pressure distr
Page 74 and 75:
Table 3.5Simulations from body-cove
Page 76 and 77:
Table 3.7Simulations from body-cove
Page 78 and 79:
61When contrasting incomplete closu
Page 80 and 81:
63800700Glottal airflowUoUg50040030
Page 82 and 83:
65Table 3.8Summary of selected glot
Page 84 and 85:
671000900Glottal airflowUoUg500400G
Page 86 and 87:
69Table 3.9Summary of selected glot
Page 88 and 89:
713.3 DiscussionThe initial observa
Page 90 and 91:
73chapter better represented the no
Page 92 and 93:
754.1 MethodsThe vocal exercises an
Page 94 and 95:
Fig. 4.1. High-speed video measurem
Page 96 and 97:
79from the subject’s mouth (air-b
Page 98 and 99:
81Instabilities occurring when F 0
Page 100 and 101:
83Fig. 4.3. Endoscopic view obtaine
Page 102 and 103:
85Table 4.1Pitch glides exhibiting
Page 104 and 105:
87CV mask and endoscope on the unst
Page 106 and 107:
89excursion was observed right befo
Page 108 and 109:
91the 50 ms following the break. Th
Page 110 and 111:
Fig. 4.9. Synchronous representatio
Page 112 and 113:
95Table 4.3HSV measures taken from
Page 114 and 115:
970Falsetto register0Chest register
Page 116 and 117:
99To better describe the EOF weight
Page 118 and 119:
101the acoustically-induced case wh
Page 120 and 121:
103to evaluate the most adequate cl
Page 122 and 123:
1055. BIOSENSING CONSIDERATIONS FOR
Page 124 and 125:
107artificial compound (Akton of 1/
Page 126 and 127:
Fig. 5.2. Bioacoustic Transducer Te
Page 128 and 129:
111subjects were in the 20-30 age r
Page 130 and 131:
1135.1.3 Relationship between sensi
Page 132 and 133:
115Fig. 5.4. Tissue-borne and air-b
Page 134 and 135:
Fig. 5.5. Effect on the air-borne s
Page 136 and 137:
119Fig. 5.7. Changes in the respons
Page 138 and 139:
Fig. 5.9. Effect of different surfa
Page 140 and 141:
123favoring the tissue-borne path b
Page 142 and 143:
1255.3.3 Translating the sensitivit
Page 144 and 145:
1276. COUPLED AND UNCOUPLED IMPEDAN
Page 146 and 147:
129Fig. 6.1. Representation of a di
Page 148 and 149:
131(a) Vowel /a/(b) Vowel /i/Fig. 6
Page 150 and 151:
133andZ rad = jωM accA acc. (6.10)
Page 152 and 153:
135Fig. 6.6. Laser grid used for HS
Page 154 and 155:
137experimentally [64] and thus wer
Page 156 and 157:
139viscous losses, inertance, and c
Page 158 and 159:
141schemes were noted, particularly
Page 160 and 161:
143Airflow (cm 3 /s)400350300250200
Page 162 and 163:
145Nevertheless, it was noted that
Page 164 and 165:
147Airflow (cm 3 /s)350300250200150
Page 166 and 167:
149(a) Vowel /a/ - fully open(b) Vo
Page 168 and 169:
151for the chest register. These tr
Page 170 and 171:
153750700Estimates from glottal air
Page 172 and 173:
155It is noticeable from these comp
Page 174 and 175:
157300250Estimates of glottal airfl
Page 176 and 177:
159250200Estimates of glottal airfl
Page 178 and 179:
161signal to derive useful quantiti
Page 180 and 181:
163invariant impedance ( ˜Z g ), d
Page 182 and 183:
165Uncoupled glottal volume velocit
Page 184 and 185:
167500450400Linearized glottal impe
Page 186 and 187:
169500450400Linearized glottal impe
Page 188 and 189:
171The estimated uncoupled airflows
Page 190 and 191:
173600500Uncoupled glottal volume v
Page 192 and 193:
175600500Uncoupled glottal volume v
Page 194 and 195:
177200Linearized glottal impedanceZ
Page 196 and 197:
179Uncoupled glottal volume velocit
Page 198 and 199:
1816.4 DiscussionNumerical simulati
Page 200 and 201:
183less pronounced coupling (i.e.,
Page 202 and 203:
1857. CONCLUSIONSThe principal aims
Page 204 and 205:
187The biosensing experiments indic
Page 206 and 207:
LIST OF REFERENCES
Page 208 and 209:
190[13] K. N. Stevens, Acoustic pho
Page 210 and 211:
192[42] B. H. Story and I. R. Titze
Page 212 and 213:
194[74] I. R. Titze, “Regulating
Page 214 and 215:
196[105] C. Tao and J. J. Jiang,
Page 216 and 217:
198[135] J. Makhoul, “Linear pred
Page 218 and 219:
200[166] J. Xu, J. Cheng, and Y. Wu
Page 220 and 221:
202[194] J. G. Švec, F. Šram, and
Page 222 and 223:
VITA
show all

ACOUSTIC COUPLING IN PHONATION AND ITS EFFECT ON ...

Create successful ePaper yourself

Delete template?

Save as template?