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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.
41

Výpočtové modelování interakce kmitajících hlasivek s proudem vzduchu / Computational modelling of interaction between oscillating vocal folds and air flow

Pavlica, Ondřej January 2011 (has links)
Master thesis deals with creating numerical model of the human vocal folds. Calculation algorithm includes interaction between vocal chords and the air flow. Modal analysis of structural and acoustic environment, backround research of vocal folds function and summary of some published overviews of numerical models are parts of this work. Analysis of the results achieved by the numerical simulations and calculations are focused on the pressure and velocity conditions in the areas under vocal folds, between vocal folds and above vocal folds. Movement and stress analysis of individual layers of vocal folds has been made. Impact of tissue thickness on resulting behaviour has been assessed.
42

Gender Perception Dependent on Fundamental Frequency, Source Spectral Tilt, and Formant Frequencies

Neuhaus, TJ 28 August 2020 (has links)
No description available.
43

Efficient 3D Acoustic Simulation of the Vocal Tract by Combining the Multimodal Method and Finite Elements

Blandin, Rémi, Arnela, Marc, Félix, Simon, Doc, Jean-Baptiste, Birkholz, Peter 22 February 2024 (has links)
Acoustic simulation of sound propagation inside the vocal tract is a key element of speech research, especially for articulatory synthesis, which allows one to relate the physics of speech production to other fields of speech science, such as speech perception. Usual methods, such as the transmission line method, have a very low computational cost and perform relatively good up to 4-5 kHz, but are not satisfying above. Fully numerical 3D methods such as finite elements achieve the best accuracy, but have a very high computational cost. Better performances are achieved with the state of the art semi-analytical methods, but they cannot describe the vocal tract geometry as accurately as fully numerical methods (e.g. no possibility to take into account the curvature). This work proposes a new semi-analytical method that achieves a better description of the three-dimensional vocal-tract geometry while keeping the computational cost substantially lower than the fully numerical methods. It is a multimodal method which relies on two-dimensional finite elements to compute transverse modes and takes into account the curvature and the variations of crosssectional area. The comparison with finite element simulations shows that the same degree of accuracy (about 1% of difference in the resonance frequencies) is achieved with a computational cost about 10 times lower.
44

Vocal changes in animals during disorders / Stimmveränderungen bei Tieren im Krankheitsfall

Riede, Tobias 26 June 2000 (has links)
Welchen Einfluß hat eine Erkrankung der lautgenerierenden Strukturen auf das Lautprodukt. Wie kann eine Stimmveränderung beschrieben werden? Diese Fragen waren zentrales Thema der Untersuchungen. Es wurde ausschließlich auf Senderseite gearbeitet und das akustische Signal und sein Generierungsmechanismus betrachtet. Zunächst wurden nichtlineare Phänomene in drei Fallstudien betrachtet. Nichtlineare Phänomene sind akustische Ereignisse, die auf ein besonderes Schwingungsverhalten der Stimmlippen zurückzuführen sind. In allen drei Fällen kamen nichtlineare Phänomene am häufigsten bei dem erkrankten Tier vor. In einer weiteren Untersuchung wurde der Harmonischen-Rausch-Abstand auf Hundebellen angewendet. Dieser akustische Parameter wurde bisher noch nicht in der Bioakustik verwendet. Normal klingende Hunde scheinen einen mittleren HNR Bereich einzunehmen, während Hunde mit Dysphonie außerhalb dieses Bereiches liegen. Außerdem wurden Untersuchungen zur Anatomie der Stimmlippen und des Vokaltraktes durchgeführt, um bestimmte Aspekte der laryngealen Stimmgenerierung zu verstehen. Diese Dissertation enthält WAVE-Datein, welche hier heruntergeladen werden können: Attached Audiofiles. / If the sender's physiology or merely the sound generating apparatus is affected by a disease, what impact on voice does it have? How can this vocal change be described? Those questions were the central issue in this work, consequently this work is focussed on the sender's side - the acoustic signal and the mechanism of sound production. First nonlinear phonemena, acoustic events arising from certain vibration patterns of the vocal folds were investigated in three case studies. In all three cases the amount of nonlinear phenomena was higher in the disordered animal. Second, the harmonic-to-noise-ratio (HNR), an acoustic parameter not yet used in animal bioacoustics, was applied to dog barks to quantify dysphonia. Normal sounding dogs occupy a middle HNR range, while dysphonic dogs exceed this range to higher as well as to lower HNR values. Additionally, certain aspects of the vocal fold and vocal tract anatomy were investigated in respect to their significance for laryngeal sound generation. This dissertation contains WAVE-files which can be downloaded here: Attached Audiofiles.
45

Säg Bob! : Sex sångare om nedsjungning

Johansson, Joel January 2021 (has links)
Detta är en kvalitativ studie med kvantitativa inslag med syftet att undersöka sångares upplevelser avnedsjungning efter högintensiv sång. Till en början har specifikt designade sångövningar förmedlats till sex medverkande sångare om fyra kvinnor och två män under individuella sånglektioner. Deltagarna har i en variant av crossover design skattat sin dagliga rösthälsa i EASE- självskattningsformulär för friska röster. Testperioden om tre veckor följdes sedan av kvalitativa intervjuer. Resultat visar att även om sångares vardag är komplex, i och med inre och yttre påverkande faktorer, har nedsjungning en upplevd effekt i avseendet förbättrad rösthälsa efter högintensiv sång. Detta gäller särskilt de kvinnliga sångarna som beskriver att nedsjungning bidragit till en mer samlad röst med minskad heshet och svullnad. Vidare rapporteras om större lätthet inför att sjunga i lägre delen av bröstregistret, en mer egaliserad röst och en förbättrad tal- och magstödsteknik tillsammans med större lätthet inför påföljande sångpass. Nedsjungning ses också ha skapat ett andrum i vardagen där minskad stress, prestationskrav och resultatinriktning omvänts till en samlad känsla av avslut. Likväl är begrepp som nedsjungning, att sjunga ned, kyla ned, eller att stretcha rösten nya begrepp som rekommenderas att vidare studeras och förmedlas till elever och studenter, framför allt då föreliggande studies resultat visar tydliga attitydskillnader avseende rösthälsa och röstvård emellan de olika könen. / This is a study regarding singers' experiences of a vocal-cool down routine preceded with a heavy vocal load. The study is mainly based on a qualitative approach with quantitative elements. At first individual singing lessons where held, whereas specifically designed vocal-cool down exercises were taught to six participating singers; four women and two men. With a modification of a crossover design the singers in this study have estimated their daily voice health in the Evaluation of the Ability to Sing Easily survey (EASE). After a three week period of tests the singers were interviewed. The result of this study shows that even if singers' everyday lives are complex due to internal and external factors, vocal- cool down where perceived as an improvement of voice health. It is mainly the female singers' that describes an increased vocal well-being, with less hoarseness and swollen vocal folds after a heavy vocal load, followed by a vocal -cool down routine. Furthermore a greater sense of ease was reported in terms of transitions between registers in the singing voice, where fatigue in the surrounding muscles also decreased alongside with a positive impact on the speaking voice, reaching lower notes in chest register and extended diaphragm breathing. The vocal cool-down routine itself also gave an unexpected finding in terms of being contemplative and relaxing for the singers; creating a breathing space in everyday life where stress, performance anxiety and other concerns where easier to let go of, with an overall feeling of closure. Vocal cool down, cooling down the voice, vocal stretch, or warming down your voice are all relatively new concepts that are recommended to be studied further, spread and taught to students and pupils, - especially as the result in this study indicates clear differences in attitudes regarding voice health in-between the male and female genders.
46

Detekce nemocí pomocí analýzy hlasu / Voice Analysis for Detection of Diseases

Chytil, Pavel January 2008 (has links)
Tato disertační práce je zaměřena na analýzu řečového signálu za učelem detekce nemocí ovlivňujících strukturu hlasových orgánů, obzvláště těch, které mění strukturální character hlasivek. Poskytnut je přehled současných technik. Dále jsou popsány zdroje použitých nahrávek pro zdravé a nemocné mlučí. Hlavním učelem této disertační práce je popsat vypočetní postup k odhadu parametrů modelu hlasového zdroje, které umožní následnou detekci a klasifikaci nemocí hlasivek. Poskytujeme detailní popis analýzy řečových signálů, které mohou být odvozeny z parametrických modelů hlasivek.
47

The language learning infant: Effects of speech input, vocal output, and feedback

Gustavsson, Lisa January 2009 (has links)
This thesis studies the characteristics of the acoustic signal in speech, especially in speech directed to infants and in infant vocal development, to gain insight on essential aspects of speech processing, speech production and communicative interaction in early language acquisition. Three sets of experimental studies are presented in this thesis. From a phonetic point of view they investigate the fundamental processes involved in first language acquisition. The first set (study 1.1 and study 1.2) investigated how linguistic structure in the speech signal can be derived and which strategy infants and adults use to process information depending on its presentation. The second set (study 2.1 and study 2.2) studied acoustic consequences of the anatomical geometry of the infant vocal tract and the development of sensory-motor control for articulatory strategies. The third set of studies (study 3.1 and study 3.2) explored the infant's interaction with the linguistic environment, specifically how vocal imitation and reinforcement may assist infants to converge towards adult-like speech. The first set of studies suggests that structure and quality of simultaneous sensory input impact on the establishment of initial linguistic representations. The second set indicates that the anatomy of the infant vocal tract does not constrain the production of adult-like speech sounds and that some degree of articulatory motor control is present from six months of age. The third set of studies suggests that the adult interprets and reinforces vocalizations produced by the infant in a developmentally-adjusted fashion that can guide the infant towards the sounds of the ambient language. The results are discussed in terms of essential aspects of early speech processing and speech production that can be accounted for by biological general purpose mechanisms in the language learning infant. / För att köpa boken skicka en beställning till exp@ling.su.se/ To order the book send an e-mail to exp@ling.su.se
48

Transforming high-effort voices into breathy voices using adaptive pre-emphasis linear prediction

Nordstrom, Karl 29 April 2008 (has links)
During musical performance and recording, there are a variety of techniques and electronic effects available to transform the singing voice. The particular effect examined in this dissertation is breathiness, where artificial noise is added to a voice to simulate aspiration noise. The typical problem with this effect is that artificial noise does not effectively blend into voices that exhibit high vocal effort. The existing breathy effect does not reduce the perceived effort; breathy voices exhibit low effort. A typical approach to synthesizing breathiness is to separate the voice into a filter representing the vocal tract and a source representing the excitation of the vocal folds. Artificial noise is added to the source to simulate aspiration noise. The modified source is then fed through the vocal tract filter to synthesize a new voice. The resulting voice sounds like the original voice plus noise. Listening experiments were carried out. These listening experiments demonstrated that constant pre-emphasis linear prediction (LP) results in an estimated vocal tract filter that retains the perception of vocal effort. It was hypothesized that reducing the perception of vocal effort in the estimated vocal tract filter may improve the breathy effect. This dissertation presents adaptive pre-emphasis LP (APLP) as a technique to more appropriately model the spectral envelope of the voice. The APLP algorithm results in a more consistent vocal tract filter and an estimated voice source that varies more appropriately with changes in vocal effort. This dissertation describes how APLP estimates a spectral emphasis filter that can transform the spectral envelope of the voice, thereby reducing the perception of vocal effort. A listening experiment was carried out to determine whether APLP is able to transform high effort voices into breathy voices more effectively than constant pre-emphasis LP. The experiment demonstrates that APLP is able to reduce the perceived effort in the voice. In addition, the voices transformed using APLP sound less artificial than the same voices transformed using constant pre-emphasis LP. This indicates that APLP is able to more effectively transform high-effort voices into breathy voices.
49

Adaptation de clones orofaciaux à la morphologie et aux stratégies de contrôle de locuteurs cibles pour l'articulation de la parole / Adaptation of orofacial clones to the morphology and control strategies of target speakers for speech articulation

Valdés Vargas, Julian Andrés 28 June 2013 (has links)
La capacité de production de la parole est apprise et maintenue au moyen d'une boucle de perception-action qui permet aux locuteurs de corriger leur propre production en fonction du retour perceptif reçu. Ce retour est auditif et proprioceptif, mais pas visuel. Ainsi, les sons de parole peuvent être complétés par l'affichage des articulateurs sur l'écran de l'ordinateur, y compris ceux qui sont habituellement cachés tels que la langue ou le voile du palais, ce qui constitue de la parole augmentée. Ce type de système a des applications dans des domaines tels que l'orthophonie, la correction phonétique et l'acquisition du langage. Ce travail a été mené dans le cadre du développement d'un système de retour articulatoire visuel, basé sur la morphologie et les stratégies articulatoires d'un locuteur de référence, qui anime automatiquement une tête parlante 3D à partir du son de la parole. La motivation de cette recherche était d'adapter ce système à plusieurs locuteurs. Ainsi, le double objectif de cette thèse était d'acquérir des connaissances sur la variabilité inter-locuteur, et de proposer des modèles pour adapter un clone de référence, composé de modèles des articulateurs de la parole (lèvres, langue, voile du palais, etc.), à d'autres locuteurs qui peuvent avoir des morphologies et des stratégies articulatoires différentes. Afin de construire des modèles articulatoires pour différents contours du conduit vocal, nous avons d'abord acquis des données qui couvrent l'espace articulatoire dans la langue française. Des Images médio-sagittales obtenues par Résonance Magnétique (IRM) pour onze locuteurs francophones prononçant 63 articulations ont été recueillis. L'un des principaux apports de cette étude est une base de données plus détaillée et plus grande que celles disponibles dans la littérature. Cette base contient, pour plusieurs locuteurs, les tracés de tous les articulateurs du conduit vocal, pour les voyelles et les consonnes, alors que les études précédentes dans la littérature sont principalement basées sur les voyelles. Les contours du conduit vocal visibles dans l'IRM ont été tracés à la main en suivant le même protocole pour tous les locuteurs. Afin d'acquérir de la connaissance sur la variabilité inter-locuteur, nous avons caractérisé nos locuteurs en termes des stratégies articulatoires des différents articulateurs tels que la langue, les lèvres et le voile du palais. Nous avons constaté que chaque locuteur a sa propre stratégie pour produire des sons qui sont considérées comme équivalents du point de vue de la communication parlée. La variabilité de la langue, des lèvres et du voile du palais a été décomposé en une série de mouvements principaux par moyen d'une analyse en composantes principales (ACP). Nous avons remarqué que ces mouvements sont effectués dans des proportions différentes en fonction du locuteur. Par exemple, pour un déplacement donné de la mâchoire, la langue peut globalement se déplacer dans une proportion qui dépend du locuteur. Nous avons également remarqué que la protrusion, l'ouverture des lèvres, l'influence du mouvement de la mâchoire sur les lèvres, et la stratégie articulatoire du voile du palais peuvent également varier en fonction du locuteur. Par exemple, certains locuteurs replient le voile du palais contre la langue pour produire la consonne /ʁ/. Ces résultats constituent également une contribution importante à la connaissance de la variabilité inter-locuteur dans la production de la parole. Afin d'extraire un ensemble de patrons articulatoires communs à différents locuteurs dans la production de la parole (normalisation), nous avons basé notre approche sur des modèles linéaires construits à partir de données articulatoires. Des méthodes de décomposition linéaire multiple ont été appliquées aux contours de la langue, des lèvres et du voile du palais ... / The capacity of producing speech is learned and maintained by means of a perception-action loop that allows speakers to correct their own production as a function of the perceptive feedback received. This auto feedback is auditory and proprioceptive, but not visual. Thus, speech sounds may be complemented by augmented speech systems, i.e. speech accompanied by the virtual display of speech articulators shapes on a computer screen, including those that are typically hidden such as tongue or velum. This kind of system has applications in domains such as speech therapy, phonetic correction or language acquisition in the framework of Computer Aided Pronunciation Training (CAPT). This work has been conducted in the frame of development of a visual articulatory feedback system, based on the morphology and articulatory strategies of a reference speaker, which automatically animates a 3D talking head from the speech sound. The motivation of this research was to make this system suitable for several speakers. Thus, the twofold objective of this thesis work was to acquire knowledge about inter-speaker variability, and to propose vocal tract models to adapt a reference clone, composed of models of speech articulator's contours (lips, tongue, velum, etc), to other speakers that may have different morphologies and different articulatory strategies. In order to build articulatory models of various vocal tract contours, we have first acquired data that cover the whole articulatory space in the French language. Midsagittal Magnetic Resonance Images (MRI) of eleven French speakers, pronouncing 63 articulations, have been collected. One of the main contributions of this study is a more detailed and larger database compared to the studies in the literature, containing information of several vocal tract contours, speakers and consonants, whereas previous studies in the literature are mostly based on vowels. The vocal tract contours visible in the MRI were outlined by hand following the same protocol for all speakers. In order to acquire knowledge about inter-speaker variability, we have characterised our speakers in terms of the articulatory strategies of various vocal tract contours like: tongue, lips and velum. We observed that each speaker has his/her own strategy to achieve sounds that are considered equivalent, among different speakers, for speech communication purposes. By means of principal component analysis (PCA), the variability of the tongue, lips and velum contours was decomposed in a set of principal movements. We noticed that these movements are performed in different proportions depending on the speaker. For instance, for a given displacement of the jaw, the tongue may globally move in a proportion that depends on the speaker. We also noticed that lip protrusion, lip opening, the influence of the jaw movement on the lips, and the velum's articulatory strategy can also vary according to the speaker. For example, some speakers roll up their uvulas against the tongue to produce the consonant /ʁ/ in vocalic contexts. These findings also constitute an important contribution to the knowledge of inter-speaker variability in speech production. In order to extract a set of common articulatory patterns that different speakers employ when producing speech sounds (normalisation), we have based our approach on linear models built from articulatory data. Multilinear decomposition methods have been applied to the contours of the tongue, lips and velum. The evaluation of our models was based in two criteria: the variance explanation and the Root Mean Square Error (RMSE) between the original and recovered articulatory coordinates. Models were also assessed using a leave-one-out cross validation procedure ...
50

O comportamento vocal entre escolares com queixas vocais, com e sem história de situação de rua, em Aracaju, Brasil

Sales, Neuza Josina 22 May 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Objective: it is to compare the frequency of vocal, acoustical and otorhinolaryngological alterations among students who present vocal complaints and street background or not. Method: cross sectional with control group. A random sample of 200 students with a street situation background was selected, aging from 07 to 10, both male and female and all took part in a playful workshop with interviews and vocal assessment afterwards. Out of them, 106 were identified as having voice alteration and/or vocal complaint, which became the study group. This group was then sent to a speech evaluation (hearing perception analysis and spectrography) and an otorhinolaryngological evaluation (physical examination and flexible videonasopharyngealaryngoscopy). The same procedures were performed in 400 students with no street situation background and, after a vocal assessment there were a total of 90 children which became the control group. Results: in the vocal assessment there was a higher incidence of vocal complaints related and/or identified in the risk group accounting 106 (17%) children who also presented characteristics of professional use of spoken voice. In the functional speech diagnosis the control group presented higher incidence of dysphonia accounting 73 (37%) in relation to the risk group. The acoustical analysis presented significant difference (p<0,01) between the two groups. In the otorhinolaryngological evaluation there was equal distribution, among the groups, of otological pathologies accounting 12 (8%), pharyngeal tonsil hypertrophy accounting 100 (67%) and varied laryngeal pathologies. The control group presented higher incidence of palato tonsil hypertrophy accounting 18 (12%) and in the risk group there was a higher incidence of nasal alterations accounting 52 (34%) and triangular medium posterior glottic gap accounting 30 (20%). Conclusion: in the control group there was a higher incidence of hoarseness, harshness and breathiness at a discrete and moderate degree and strained quality voice at a moderate degree associated to palato tonsil hypertrophy and computer acoustical parameters of significantly poor quality in relation to the risk group. The risk group makes professional use of spoken voice with high incidence of normal voice, nasal alterations and triangular medium posterior glottic gap, besides computer acoustical parameters of significantly higher quality in relation to the control group. / Objetivo: Comparar a distribuição das alterações vocais, acústicas e otorrinolaringológicas entre escolares com queixas vocais, com ou sem história de situação de rua. Método: transversal com grupo controle. Foi selecionada uma amostra aleatória de 200 escolares com história de situação de rua, com idade entre 07-10 anos, de ambos os sexos. Todos participaram de oficina lúdica, com entrevista e triagem vocal posterior. Destas, 106 crianças foram identificadas com alteração vocal e/ou relataram queixa vocal que se constituiu no grupo de estudo. Este grupo foi encaminhado para avaliação fonoaudiológica (análise perceptivo-auditiva e espectrografia) e avaliação otorrinolaringológica (exame físico e vídeonasofaringolaringoscopia flexível). Os mesmos procedimentos foram realizados com 400 escolares, sem história de situação de rua e após triagem vocal formou-se um total de 90 crianças que se constituiu no grupo controle. Resultados: Na triagem vocal houve significância de queixas vocais relatadas e/ou identificadas em 106 (17%) crianças do grupo de risco e que também apresentou características de uso profissional da voz falada No diagnóstico fonoaudiológico o grupo controle apresentou significância de disfonia em 73 (37%) crianças em relação ao grupo de risco. Na análise acústica computadorizada houve diferenças significativas (p<0,01) entre os dois grupos. Na avaliação otorrinolaringológica ocorreu distribuição igual entre os grupos de alterações otológicas 12 (8%), hipertrofia de tonsila faríngea 100 (67%) e alterações laríngeas variadas. O grupo controle apresentou significância de hipertrofia de tonsila palatina 18 (12%) e no grupo de risco ocorreu significância de alterações nasais 52 (34%) e fenda glótica triangular média posterior 30 (20%). Conclusão: No grupo controle, houve significância no tipo de voz rouca, áspera, soprosa grau discreto e moderado e, voz tensa grau moderado associado à hipertrofia de tonsila palatina e parâmetros acústicos computadorizados com qualidade significantemente inferiores em relação ao grupo de risco. O grupo de risco faz uso profissional da voz falada com significância de voz normal, alterações nasais e fenda glótica triangular média posterior além de parâmetros acústicos computadorizados com qualidade significantemente superior em relação ao grupo controle.

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