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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

The Voice Source in Speech Communication - Production and Perception Experiments Involving Inverse Filtering and Synthesis

Gobl, Christer January 2003 (has links)
<p>This thesis explores, through a number of production andperception studies, the nature of the voice source signal andhow it varies in spoken communication. Research is alsopresented that deals with the techniques and methodologies foranalysing and synthesising the voice source. The main analytictechnique involves interactive inverse filtering for obtainingthe source signal, which is then parameterised to permit thequantification of source characteristics. The parameterisationis carried by means of model matching, using the four-parameterLF model of differentiated glottal flow.</p><p>The first three analytic studies focus on segmental andsuprasegmental determinants of source variation. As part of theprosodic variation of utterances, focal stress shows for theglottal excitation an enhancement between the stressed voweland the surrounding consonants. At a segmental level, the voicesource characteristics of a vowel show potentially majordifferences as a function of the voiced/voiceless nature of anadjacent stop. Cross-language differences in the extent anddirectionality of the observed effects suggest differentunderlying control strategies in terms of the timing of thelaryngeal and supralaryngeal gestures, as well as in thelaryngeal tensions settings. Different classes of voicedconsonants also show differences in source characteristics:here the differences are likely to be passive consequences ofthe aerodynamic conditions that are inherent to the consonants.Two further analytic studies present voice source correlatesfor six different voice qualities as defined by Laver'sclassification system. Data from stressed and unstressedcontexts clearly show that the transformation from one voicequality to another does not simply involve global changes ofthe source parameters. As well as providing insights into theseaspects of speech production, the analytic studies providequantitative measures useful in technology applications,particularly in speech synthesis.</p><p>The perceptual experiments use the LF source implementationin the KLSYN88 synthesiser to test some of the analytic resultsand to harness them to explore the paralinguistic dimension ofspeech communication. A study of the perceptual salience ofdifferent parameters associated with breathy voice indicatesthat the source spectral slope is critically important andthat, surprisingly, aspiration noise contributes relativelylittle. Further perceptual tests using stimuli with differentvoice qualities explore the mapping between voice quality andits paralinguistic function of expressing emotion, mood andattitude. The results of these studies highlight the crucialrole of voice quality in expressing affect as well as providingpointers to how it combines with<i>f</i><sub>0</sub>for this purpose.</p><p>The last section of the thesis focuses on the techniquesused for the analysis and synthesis of the source. Asemi-automatic method for inverse filtering is presented, whichis novel in that it optimises the inverse filter by exploitingthe knowledge that is typically used by the experimenter whencarrying out manual interactive inverse filtering. A furtherstudy looks at the properties of the modified LF model in theKLSYN88 synthesiser: it highlights how it differs from thestandard LF model and discusses the implications forsynthesising the glottal source signal from LF model data.Effective and robust source parameterisation for the analysisof voice quality is the topic of the final paper: theeffectiveness of global, amplitude-based, source parameters isexamined across speech tokens with large differences in<i>f</i><sub>0</sub>. Additional amplitude-based parameters areproposed to enable a more detailed characterisation of theglottal pulse.</p><p><b>Keywords:</b>Voice source dynamics, glottal sourceparameters, source-filter interaction, voice quality,phonation, perception, affect, emotion, mood, attitude,paralinguistic, inverse filtering, knowledge-based, formantsynthesis, LF model, fundamental frequency,<i>f</i><sub>0</sub>.</p>
82

Rörfonation eller traditionell svensk röstbehandling? : En jämförande studie mellan två olika metoder för röstbehandling / Tube Phonation or Traditional Swedish Voice Therapy? : A Comparative Study of two Voice Therapy Methods

Franzén, Jerker, Wijkmark, Hannes January 2013 (has links)
Rörfonation och traditionell svensk röstbehandling är två av de vanligaste behandlingsalternativen inom svensk röstlogopedi idag. Som forskare är det viktigt att kontinuerligt utvärdera de behandlingar som erbjuds för att göra vården mer kvalitativ och kostnadseffektiv. Finns det skillnader i behandlingseffekt mellan dessa två röstbehandlingar? Är skillnaderna så tydliga att det går att fastslå att den ena behandlingen är att föredra framför den andra? Med analyser av ett patientmaterial, före och efter behandling, i form av akustisk analys, perceptuella bedömningar av en grupp erfarna logopeder samt patienternas självskattningar syftar föreliggande uppsats till att besvara vad behandlingsformerna har för effekt inom dessa områden. Patientmaterialet bestod av totalt 28 patienter varav 23 fullföljde behandling. Tolv av dessa erhöll behandling med rörfonation medan resterande elva patienter erhöll traditionell svensk röstbehandling.. Utöver röstinspelningar bestod materialet av patienternas självskattningar, i form av RHI- och Swe-VAPP-formulär. Gällande behandlingseffekt på akustiska parametrar kunde inga slutsatser dras. De perceptuella parametrarna afoni, hyperfunktion och knarr förbättrades sett till hela urvalet, oavsett typ av röstbehandling. Tydliga förbättringar sågs i patienternas självskattningar efter båda behandlingsmetoderna. Röstbehandling ger således positiva resultat, men några skillnader i behandlingseffekt mellan de två olika metoderna för röstbehandling kunde inte påvisas. / Tube phonation and traditional Swedish voice therapy are two of the most common voice therapy options in Sweden today. As a researcher, it is important to continually evaluate available therapy options to make health care more qualitative and cost effective. Are there differences in treatment effect between these two voice treatments? If so, are the differences so obvious that it is possible to conclude that one treatment should be preferred over the other? Analyses of a patient material, before and after treatment, which included acoustic analysis, perceptual analysis by a group of experienced speech-language therapists and patients' selfassessments were made aiming to answer what effect the two treatment options have in these areas. The patient material consisted of 28 patients, of whom 23 completed the therapy. Twelve of them received treatment with tube phonation while the remaining eleven patients received traditional Swedish voice therapy. Besides audio recordings, the material consisted of patients' self-assessments pre- and post-therapy, including VHI and Swe-VAPP forms. The treatment effect on acoustic parameters was inconclusive. The perceptual parameters aphonia, hyper function, and creaking improved over the entire sample, regardless of the type of voice therapy. Clear improvements were seen in the patients' self-assessments after both therapy methods. Voice therapy thus gives positive results, but no differences in treatment effect between the two different methods of voice therapy were seen.
83

TEMPO MÁXIMO DE FONAÇÃO E CARACTERÍSTICAS VOCAIS ACÚSTICAS DE CRIANÇAS PRÉ-ESCOLARES / MAXIMUM PHONATION TIME AND VOCAL ACOUSTIC CHARACTERISTICS IN PRE-SCHOOL CHILDREN

Capellari, Viviane Michele 14 December 2006 (has links)
The evaluation is the first step for any treatments. Therefore, normal parameters are the bases for proper evaluation in any kind of treatments. This study aimed at verifying measures of maximum phonation time (MPT) and vocal acoustic characteristics of 23 children aged 4 to 6.08 years, whose parents had signed a Free Consent Form. The children studied in four schools that agreed to participate in this research by signing an Institutional Authorization Form. The sampling process comprised a questionnaire that was sent to parents, auditory screening and vocal perceptive-auditory assessment, based on an independent evaluation performed by four speech and language pathologists through the use of R.A.S.A.T. scale. Data collection included MPT and voice samples for acoustic analysis through Multidimensional Voice Program (Kay Elemetrics). The results showed that MPT was significantly longer in 6-year-olds than in 4-year-olds; frequency variation was significantly higher in the total sample than at ages five and six. Noise harmonic ratio of the total sample was significantly higher than in fiveyear- olds. As age increased, values of noise harmonic ratio decreased significantly; noise harmonic ratio in 4-year-olds was significantly higher than at ages five and six. As the total mean of amplitude perturbation quotient increased, frequency variation, variation of amplitude and noise harmonic ratio also increased significantly; the same occurred between total mean of noise harmonic ratio and frequency variation. As the total means of amplitude perturbation quotient, frequency perturbation quotient and voice turbulence index increased the mean of soft phonation index decreased significantly. It was concluded that the results of the acoustic parameters and MPT at the age of four years old seem to evidenceimmaturity of the structures and lack of neural-muscular control at that age. / O primeiro passo em qualquer tratamento é a avaliação. Desta forma, parâmetros de normalidade são a base para uma adequada avaliação em qualquer tipo de tratamento. O objetivo deste estudo foi verificar as medidas de tempo máximo de fonação (TMF) e as características vocais acústicas de crianças entre 4:00 e 6:00, de ambos os sexos, estudantes de pré-escolas da rede pública e privada de Porto Alegre/RS. O processo de amostragem contou com questionário enviado aos pais, triagem auditiva, e avaliação perceptivo-auditiva vocal, baseada na avaliação de 4 fonoaudiólogas, por meio da escala R.A.S.A.T. Foram coletados os TMF e da amostra vocal para análise acústica pelo Multidimensional Voice Program (Kay Elementrics). Os dados foram submetidos à análise estatística por meio dos testes: t de Student, de Spearman, Pearson e Análise de Variância- ANOVA. Os resultados evidenciaram que os TMF foram significativamente maiores aos 6:00, em comparação aos 4:00; a variação de freqüência foi significativamente maior na amostra total do que nas idades de 5:00 e 6:00; a proporção harmônicoruído da amostra total foi significativamente maior do que aos 5:00 anos; e, à medida que a idade aumentou, os valores de proporção harmônico-ruído reduziram significativamente; a proporção harmônico-ruído aos 4:00 foi significativamente maior do que aos 5:00 e 6:00; à medida que a média total do quociente de perturbação de freqüência aumentou, variação de freqüência, variação de amplitude e a proporção hamônico-ruído também aumentaram significativamente; o mesmo ocorreu entre ao média total da proporção harmônico-ruído e da variação de freqüência; à medida que as médias totais do quociente de perturbação de freqüência, do quociente de perturbação de amplitude e do índice de turbulência vocal, aumentaram, a média do índice de fonação suave reduziu significativamente. Como conclusäo, constatou-se que os parâmetros acústicos e dos TMF, na idade de 4:00, parecem evidenciar a imaturidade das estruturas e a falta de controle neuromuscular nessa idade e que o início deste processo de maturacäo, possivelmente, ocorre próximo aos 5:00 e 6:00 de idade.
84

Použití fluidně-strukturní interakce u kmitajících lidských hlasivek / Application of Fluid-structure Interaction on Oscillating Human Vocal Folds

Meisner, Patrik January 2021 (has links)
The presented thesis is involved in the biomechanics of phonation. The aim of the thesis is to set a fluid-structure interaction between the vocal folds and air flow when the pressure from lungs reaches the physiological values. In the expected outcome the self-oscillating vocal folds should be observable with characteristics shape-shift from convergent to divergent. In theory part of the thesis is described Anatomy of the vocal tract, physiology of the human phonation, research of computational simulations, experiments and visualisation methods are described in the theory part of the thesis. In the second part, setup of computational simulation with the finite element method is presented. Besides of the fluid-structure interaction the acoustical model is set. Achieved results are presented and compared to the results in literature. Displacements are evaluated from the structural model and pressures, velocities and flow velocities are evaluated from fluid model, so as acoustics results.
85

Karakteristike glasa i metodički pristupi razvoju glasa u funkciji profesionalnih aktivnosti / Voice Characteristics and MethodicalApproaches in the Voice Development for thePurpose of Professional Activities

Vitkai Kučera Agota 04 March 2013 (has links)
<p>Predmet doktorske disertacije je utvrđivanje stanja glasa budućih eltinih vokalnih profesionalaca (studenata glume), upoređivanje sa stanjem glasa studenata nevokalnih<br />zanimanja, utvrđivanje metodičkih postupaka za razvoj glasa, kao i utvrđivanje uticaja glasovnih vežbi primenom &quot;WIC&quot; tehnike na stanje glasa kod ispitanika kojima je potvrđen vokalni poremećaj.</p> / <p>This PhD thesis aims to establish the state of voice in future elite vocal professionals (drama students), to compare it with the state of voice in students of non-vocal professions, to determine the methodic procedures for the voice development, as well as to ascertain the effects of vocal exercises by application of &ldquo;WIC&rdquo; technique on the state of voice in respondents who were found to suffer from the vocal disorder.</p>
86

Výpočtové modelování samobuzeného kmitání lidských hlasivek / Computational Modelling of Self- oscillations of the Human Vocal Folds

Hájek, Petr January 2022 (has links)
The presented dissertation thesis deals with a simulation of the human phonation in terms of latest theories. Phonation is considered here as a bi-directional fluid-structure-acoustic interaction, where the interaction between all three physical domains occurs due to the unsteady viscous compressible Navier-Stokes equations. There is a solid knowledge background in the first part of the thesis. It concerns the latest concepts in computational modeling of the human phonation, the most important and recent theories about the human voice production and some key aspects of the human anatomy, physiology and pathology. Also voice assessment is discussed. The second part of the thesis describes an in-depth analysis of a phonation simulation in a planar computational model. The basic concepts proceed from algorithms developed in the Institute of Solid Mechanics, Mechatronics and Biomechanics. Created models are able to reproduce sounds of all Czech vowels and the most common evaluated parameters very close to physiological ranges. The simulated pathology, Reinke's edema, is demonstrated in order to explore its influence on the vowel sound. The third part focuses on modeling of phonation in a spatial computational model. All Czech vowels are simulated also here and compared to the planar model and to actual measurement. The spatial model serves as the starting point to modeling of a longitudinal pretension incorporated in the vocal folds. In the last part of the thesis, a modeling of the phonation with vocal folds pretension is investigated. Although the models are tuned to a rather soft phonation, the results are in agreement with the relevant physiologic phenomena. While the spatial model is highly computationally expensive, a hybrid planar model with pretension is proposed. A special attention is paid to the analysis of self-sustained oscillation of the vocal folds. It is shown, the planar model cannot reproduce such kind of oscillation in the actual version, albeit time of oscillation was considerably extended. On the other hand, oscillation of the spatial vocal folds are stabilized without effects accompanying subduing of oscillation. It can be supposed that the spatial model is able to reproduce self-sustained oscillation as a basic principle present during the human phonation.
87

Ingressive Phonation in Contemporary Vocal Music

DeBoer, Amanda R. 20 November 2012 (has links)
No description available.
88

Voice Characteristics of Preschool Age Children

Schuckman, Melanie 29 April 2008 (has links)
No description available.
89

Approximating Subglottal Pressure from Oral Pressure: A Methodological Study

Frazer, Brittany L. 11 July 2014 (has links)
No description available.
90

Primo Passaggio: Measures Associated with Different Interpretations Sung by an Elite Soprano Performer

Diaz, Raymond 25 April 2018 (has links)
No description available.

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