• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 53
  • 30
  • 14
  • 5
  • 5
  • 4
  • 4
  • 3
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 130
  • 48
  • 32
  • 30
  • 24
  • 23
  • 15
  • 14
  • 13
  • 13
  • 11
  • 10
  • 10
  • 10
  • 10
  • 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.
71

Experimental study of the tonal trailing-edge noise generated by low-reynolds number airfoils and comparison with numerical simulations / Étude expérimentale du sifflement de bord de fuite pour des profils à faible nombre de Reynolds et comparaison avec des simulations numériques

Yakhina, Gyuzel 31 January 2017 (has links)
Le bruit tonal rayonné au bord de fuite des profils à faible nombre de Reynolds est un phénomène observé sur les ailes de drones ou micro-drones qui sont utilisés partout dans la vie quotidienne. La diminution de ce bruit va augmenter la survivabilité et l'efficacité des appareils dans le domaine militaire. De plus, cela va augmenter le champ des applications civiles et minimiser la pollution par le bruit. La réduction efficace du bruit est indispensable et, par conséquent, une compréhension complète du processus de rayonnement du bruit tonal du profil est nécessaire. Malgré le fait que des essais dédiés aient été réalisés depuis les années 70, il reste beaucoup de détails à expliquer. Le travail présenté est dédié à une étude expérimentale et analytique du bruit tonal. C'est une partie de collaboration entre l'Ecole Centrale de Lyon et Embry- Riddle Aeronautical University. Le but est de réaliser une caractérisation exhaustive des paramètres acoustiques et aérodynamiques du bruit tonal de bord de fuite d'un profil et de produire une base de données qui pourra être utilisée pour valider les simulations numériques réalisées dans le futur. Le profil symétrique NACA-0012 ainsi que le profil asymétrique SD7003 ont été testés pour une série d'angles d'incidence (de -10° à 10°) dans la soufflerie anéchoïque à jet ouvert de l'Ecole Centrale de Lyon pour des nombres de Reynolds modérés (0.6x105 < Rec < 2.6x105). Les mesures de pression aux parois et de pression acoustique en champ lointain pour différentes configurations ont permis d'observer une structure en escalier de la signature du bruit, de déterminer quelle face du profil a produit le bruit et de distinguer le rôle de la boucle de rétroaction. Des techniques supplémentaires de post-traitement comme l'analyse temps-fréquence ont montré l'existence de plusieurs régimes (un régime de commutation entre deux états, un régime d'une seul fréquence et un régime à plusieurs fréquences) de l'émission de bruit. L'analyse de bi-cohérence a montré qu'il y a des couplages nonlinéaires entre les fréquences. Une étude par l'anémométrie à fil chaud et par des techniques de visualisation de l'écoulement a montré que la formation d'une bulle de décollement est une condition nécessaire mais pas suffisante pour la génération du bruit. De plus, la localisation de la bulle est aussi importante et elle doit être suffisamment proche du bord de fuite. En outre, l'analyse de stabilité linéaire des résultats de simulations numériques a montré que des ondes de Tollmien-Schlichting sont transformées en ondes de Kelvin-Helmholtz dans la zone du décollement. Une prédiction analytique de l'amplitude des fréquences pures émises dans le champ lointain a été effectuée sur la base du modèle d'Amiet en supposant que le champ de pression pariétal est bidimensionnel. Les mesures de pression proches du bord de fuite du profil ont été prises comme données d'entrée. Les amplitudes prédites sont globalement en accord avec les mesures acoustiques. Après l'analyse de tous les résultats la description suivante du processus de rayonnement de sons purs peut être proposée. Les ondes de Tollmien-Schlichting qui se développent initialement dans la couche limite se transforment en ondes de Kelvin-Helmholtz le long de la couche de cisaillement de la bulle de décollement. Au bord de fuite du profil elles sont converties en ondes acoustiques qui forment un couplage fort avec les instabilités de couche limite plus en amont de l'écoulement, pilotant elles-mêmes le déclenchement de ces instabilités. / The tonal trailing-edge noise generated by transitional airfoils is a topic of interest because of its wide area of applications. One of them is the Unmanned Air Vehicles operated at low Reynolds numbers which are widely used in our everyday life and have a lot of perspectives in future. The tonal noise reduction will increase the survivability and effectiveness of the devices in military field. Moreover it will enlarge the range of civil use and minimize noise pollution. The effective noise reduction is needed and therefore the complete understanding of the tonal noise generation process is necessary. Despite the fact that investigation of the trailing-edge noise was started since the seventies there are still a lot of details which should be explained. The present work is dedicated to the experimental and analytical investigation of the tonal noise and is a part of the collaboration project between Ecole Centrale de Lyon and Embry-Riddle Aerospace University. The aim is to conduct an exhaustive experimental characterization of the acoustic and aerodynamic parameters of the trailing-edge noise and to produce a data base which can be used for further numerical simulations conducted at Embry-Riddle Aerospace University. A symmetric NACA-0012 airfoil and a slightly cambered SD7003 airfoil at moderate angles of attack (varied from -10° à 10°) were tested in an open-jet anechoic wind tunnel of Ecole Centrale de Lyon at moderate Reynolds numbers (0.6x105 < Rec < 2.6x105). Measurements of the wall pressure and far-field acoustic pressure in different configurations allowed to observe the ladder-type structure of the noise signature, to determine which side produced tones and to distinguish the role of the acoustic feedback loop. Additional post-processing techniques such as time-frequency analysis showed the existence of several regimes (switching regime between two tones, one-tone regime and multiple-tones regime) of noise emission. The bicoherence analysis showed that there are non-linear relationships between tones. The investigation of the role of the separation area by hot-wire anemometry and flow visualization techniques showed that the separation bubble is a necessary but not a suficient condition for the noise generation. Moreover the location of the bubble is also important and should be close enough to the trailing edge. Furthermore the linear stability analysis of accompanying numerical simulation results showed that the Tollmien-Schlichting waves transform to the Kelvin-Helmholtz waves at the separation area. An analytical prediction of the tone levels in the far-field was done using Amiet's model based on the assumption of perfectly correlated sources along the span. The wall-pressure measurements close to the trailing edge were used as an input data. The comparisons of the predicted levels and measured ones showed a good agreement. After analysis of all results the following description of the tonal noise mechanism is proposed. At some initial point of the airfoil the Tollmien-Schlichting instabilities start. They are traveling downstream and continued to Kelvin-Helmholtz waves along the shear-layer of the separation bubble. These waves reach the trailing edge, scatter from it as acoustic waves, which move upstream. The acoustic waves amplify the boundary layer instabilities at some frequencies for which the phases of both motions match and creates the feedback loop needed to sustain the process.
72

Simetria na música pós-tonal. Rede de projeções por inversão / Symmetry in post-tonal music. Inversional pitch-class set network

Albuquerque, Joel Miranda Bravo de 07 November 2018 (has links)
O objetivo principal desta pesquisa é o aprimoramento de ferramentas teóricas desenvolvidas para a análise harmônica de obras de vanguarda do início do século XX e afins (incluindo algumas obras de Villa-Lobos), destacando a utilização da simetria intervalar como fator de coerência em amostras de músicas deste período e correlacionadas. Observaremos principalmente aspectos relacionados a presença de padrões intervalares simétricos por reflexão inerentes ao sistema cromático. Procurando estabelecer um arcabouço teórico consistente que contemplasse as demandas circunscritas nas músicas pós-tonais analisadas, buscamos entender a importância da simetria entre alturas em níveis estruturais mais profundos supondo que a proporcionalidade intervalar pudesse corroborar no delineamento harmônico das obras escolhidas. Nossa proposta de estudo é calcada em fundamentos e conceitos desenvolvidos por teóricos ligados às pesquisas sobre a teoria dos conjuntos, com destaque para os textos de Joseph Straus (2005). Em outra esfera, elencamos ferramentas teóricas de uma segunda abordagem metodológica que cada vez mais ganha destaque entre musicólogos que atuam no campo da análise de obras pós-tonais - a teoria neorriemanniana - em particular observando os conceitos apresentados por David Lewin (1982; 1987) e os seus desdobramentos discutidos por Richard Cohn (1998; 2012), autor em torno do qual gravita a vertente secundária conhecida como teoria transformacional. A partir da intersecção entre estas duas correntes teóricas pós-tonais escolhidas, desenvolvemos uma terceira proposta metodológica aparentemente inédita - que chamaremos neste trabalho de teoria da inversão - um desdobramento decorrente do aperfeiçoamento de conceitos da teoria neorriemanniana de David Lewin e Brian Hyer que envolvem a reflexão intervalar de conjuntos de alturas, parâmetros não contemplados pela recente teoria transformacional de Dmitri Tymoczko (2007; 2011) e Richard Cohn (1998; 2012). No âmbito desta proposição, seguindo a suposição levantada por Robert Morris (2007) de que existem aspectos fundamentais em comum entre as principais correntes teóricas dedicadas à música pós-tonal, exploramos alguns apontamentos deste autor que nos direcionaram à apropriação de ferramentas pertencentes à teoria dos grupos - campo de conhecimento oriundo da matemática, especializada no estudo de simetria utilizando estruturas algébricas conhecidas como matrizes. Deste processo surge a descoberta de um conglomerado de classes de conjuntos que podem ser alinhados em uma mesma rede de projeções por inversão. Avaliando os aspectos inerentes a este sistema apresentado, identificamos a construção de toda uma estrutura em disposição espelhada, revelando a existência de uma simetria transversal que abrange um grande número de conjuntos de alturas inerentes ao universo das doze alturas, confirmando a hipótese levantada por Robert Morris. Verificamos ainda outras correlações entre os conjuntos correspondentes presentes nesta rede de projeções por inversão - relações por multiplicação pelo fator M5 e M7 e invariância entre entradas de vetores intervalares (RAHN, 1980; OLIVEIRA, 2007) - que corroboram a constatação desta dimensão simétrica envolvendo o campo harmônico cromático. Outra proposta neste trabalho foi a ampliação na gama de possibilidades de utilização de redes de alturas (Tonnetze) - ferramenta emblemática da teoria neorriemanniana - apresentando outras opções de conjuntos para os desdobramentos por inversões, indo além dos convencionais conjuntos 3-11 (tricorde Maior e menor) e 4-27 (tetracordes Maior 7 e meio diminuto) recorrentes em formatações tradicionais. Seguindo neste propósito, desenvolvemos aprofundamentos abrangendo a remota rede de alturas de Euler com o tetracorde 4-20 e o Tonnetz tridimensional de Gollin (1998), alinhando esta pesquisa também aos resultados encontrados por Henri Pousseur ([1968], 2009) em suas \"redes harmônicas\" e aos conceitos desenvolvidos por George Perle (1977) e sua \"teoria dos ciclos intervalares\". / The main objective of this research is to improve the theoretical tools developed for the harmonic analysis of the early works of the early 20th century and related works (including some works by Villa-Lobos), highlighting the use of interval symmetry as a coherence factor in samples of pieces from this period and correlated. We will mainly observe aspects related to the presence of symmetrical interval patterns by reflection inherent to the chromatic system. We will mainly observe aspects related to the presence of symmetrical interval patterns by reflection inherent to the chromatic system. In order to establish a consistent theoretical framework that contemplates the circumscribed demands in the analyzed post-tonal pieces, we sought to understand the importance of symmetry by comparing pitches at deeper structural levels, assuming that the interval proportionality could corroborate the harmonic delineation of the chosen works. Our proposal is based on fundamentals and concepts developed by theorists related to research on pitch-class set theory, especially the texts of Joseph Straus (2005). Our study proposal is based on fundamentals and concepts developed by theorists related to research on pitch-class set theory, especially the texts of Joseph Straus (2005). In another sphere, we have ellipped theoretical tools of a second methodological approach that is increasingly prominent among musicologists working in the field of post-tonal analysis - neo-Riemannian theory - in particular, observing the concepts presented by David Lewin (1982, 1987) and its ramifications discussed by Richard Cohn (1998, 2012), author around which gravitates the secondary slope known as transformational theory. From the intersection between these two post-tonal theoretical currents chosen, we have developed a third methodological proposal that is apparently unpublished - which we will call inversional pitch-class set theory - an unfolding resulting from the refinement of David Lewin and Brian Hyer\'s concepts of neo-Riemannian theory involving interval analysis of sets of pitch-class sets, parameters not contemplated by the recent transformational theory of Dmitri Tymoczko (2007; 2011) and Richard Cohn (1998, 2012). In this context, following the assumption made by Robert Morris (2007) that there are fundamental aspects in common among the main theoretical currents dedicated to post-tonal music, we explore some notes of this author that have directed us to the appropriation of tools belonging to the theory of groups - field of knowledge from mathematics, specialized in the study of symmetry using algebraic structures known as matrices. From this process comes the discovery of a conglomeration of pitch-class sets that can be aligned in the same inversional pitch-class set network. Evaluating the inherent aspects of this system, we identified the construction of a whole structure in a mirrored arrangement, revealing the existence of a transversal symmetry that covers a substantial number of pitch-class sets inherent to the universe of the twelve pitches, confirming the hypothesis raised by Robert Morris. We also verified other correlations between the corresponding sets in this inversional pitch-class set network - relations by multiplication by the factor M5 and M7 and invariance between interval vectors (RAHN, 1980; OLIVEIRA, 2007) - which corroborate the observation of this symmetrical dimension involving the chromatic harmonic field. Another proposal in this work was the expansion of the range of possibilities of use of pitch-classes networks (Tonnetze) - emblematic tool of the neo-Riemannian theory - presenting other options of sets for the inversion unfolding, going beyond the conventional sets 3-11 (Major and minor chord) and 4-27 (Major 7th and half-diminished 7th chords) recurrent in traditional formatting. Following this, we developed deepening studies covering the remote pitch-class network of Euler with the tetrachord 4-20 and Gollin\'s three-dimensional Tonnetz (1998), aligning this research also with the results found by Henri Pousseur ([1968], 2009) about his harmonic networks and the concepts developed by George Perle (1977) and his \"interval cycles theory\".
73

Tonal description of music audio signals

Gómez Gutiérrez, Emilia 25 July 2006 (has links)
Aquesta tesi doctoral proposa i avalua un enfocament computacional per a la descripció automàtica dels aspectes tonals de la música a partir de l'anàlisi de senyals d'-audio polifòniques. Aquests mètodes es centren en el càlcul de descriptors de distribucions de notes, en l'estimació de tonalitat d'una peça, en la visualització de l'evolució del centre tonal o en la mesura de la similitud tonal entre dues peces diferents. Aquesta tesi contribueix substancialment al camp de la descripció tonal mitjançant mètodes computacionals: a) Proporciona una revisió multidisciplinària dels sistemes d'estimació de la tonalitat; b) Defineix una sèrie de requeriments que han de complir els descriptors tonals de baix nivell; c) Proporciona una avaluació quantitativa i modular dels mètodes proposats; d) Justifica la idea de que per a certes aplicacions es poden fer servir mètodes que treballen amb partitures sense la necessitat de realitzar una transcripció automàtica e) Estén la literatura existent que treballa amb música clàssica a altres generes musicals; f) Demostra la utilitat dels descriptors tonals per a comparar peces musicals; g) Proporciona un algoritme optimitzat que es fa servir dins un sistema real per a visualització, cerca i recomanació musical, que treballa amb més d'un milió de obres musicals. / Esta tesis doctoral propone y evalúa un enfoque computacional para la descripción automática de aspectos tonales de la música a partir del análisis de señales de audio polifónicas. Estos métodos se centran en calcular descriptores de distribución de notas, en estimar la tonalidad de una pieza, en visualizar la evolución del centro tonal o en medir la similitud tonal entre dos piezas diferentes.Esta tesis contribuye sustancialmente al campo de la descripción tonal mediante métodos computacionales: a) Proporciona una revisión multidisciplinar de los sistemas de estimación de la tonalidad; b) Define una serie de requerimientos que deben cumplir los descriptores tonales de bajo nivel; c) Proporciona una evaluación cuantitativa y modular de los métodos propuestos; d) Respalda la idea de que para ciertas aplicaciones no es necesario obtener una transcripción perfecta de la partitura, y que se pueden utilizar métodos que trabajan con partituras sin realizar una transcripción automática; e) Extiende la literatura existente que trabaja con música clásica a otros géneros musicales; f) Demuestra la utilidad de los descriptores tonales para comparar piezas musicales; g) Proporciona un algoritmo optimizado que se utiliza en un sistema real para visualización, búsqueda y recomendación musical, que trabaja con mas de un millón de piezas musicales. / This doctoral dissertation proposes and evaluates a computational approach for the automatic description of tonal aspects of music from the analysis of polyphonic audio signals. These algorithms focus on the computation of pitch class distributions descriptors, the estimation of the key of a piece, the visualization of the evolution of its tonal center or the measurement of the similarity between two different musical pieces.This dissertation substantially contributes to the field of computational tonal description: a) It provides a multidisciplinary review of tonal induction systems; b) It defines a set of requirements for low-level tonal features; c) It provides a quantitative and modular evaluation of the proposed methods; d) It contributes to bridge the gap between audio and symbolic-oriented methods without the need of a perfect transcription; e) It extents current literature dealing with classical music to other musical genres; f) It shows the usefulness of tonal descriptors for music similarity; g) It provides an optimized method which is used in a real system for music visualization and retrieval, working with over a million of musical pieces.
74

Contribution à la prévision du bruit tonal des machines tournantes subsoniques : couplage des simulations numériques et des modèles analytiques avec les analogies acoustiques

Tannoury, Elias 05 July 2013 (has links) (PDF)
La conception des groupes moto-ventilateurs au sein de Valeo Systèmes Thermiques et la prédiction de leurs performances aérauliques reposent majoritairement sur les méthodes de développement virtuel, i.e. la conception assistée par ordinateur et la simulation numérique de la mécanique des fluides. Dans ce cadre, le présent travail propose une méthodologie de prédiction et de minimisation de la composante tonale du bruit d'un groupe moto-ventilateur. L'approche adoptée est hybride et dissocie la génération et la propagation du bruit. La propagation en champ libre est calculée avec une formulation intégrale de l'analogie de Ffowcs-Williams et Hawkings. Dans un premier temps, les termes-sources à la surface du rotor et du stator sont calculés par une simulation numérique instationnaire. La compacité de la pale ainsi que l'influence du maillage acoustique sur la prédiction sont ensuite investiguées. Finalement, les résultats sont comparés aux mesures expérimentales. Dans un deuxième temps, les sources acoustiques à la surface du stator sont calculées avec le modèle de Sears enrichi avec des données extraites d'une simulation stationnaire du rotor complet. Avant de procéder à la prédiction acoustique, l'influence du modèle de turbulence sur les résultats finaux est évaluée à travers une comparaison entre LES et RANS pour l'écoulement autour de profils extrudés. Enfin, la problématique de minimisation du bruit tonal est traitée en tant que problème d'optimisation où la géométrie d'une aube est paramétrée et où la recherche de l'optimum est conduite par un algorithme génétique. Cette optimisation a permis de concevoir un stator moins bruyant et adapté à l'écoulement en aval du rotor étudié.
75

An Analysis of Phrase Structures in the First Movement of Leo Brouwer’s Elogio De La Danza (1964)

Focsaneanu, Bogdan Vasile 13 September 2012 (has links)
This study examines phrase and larger formal structures in the first movement of Leo Brouwer’s Elegio de la Danza (1964), a work that draws on tonal and post-tonal traditions. By adapting key features of the tonal motive, as described by Douglass Green, and the tonal period, as proposed by Green and William Caplin, the model seeks to provide a tool for the discussion of phrases and larger forms in Brouwer’s work. An analysis of primary parameters, such as melody, harmony, and rhythm, provides the means to discuss how the composer articulates beginnings and endings of statements and responses, which are then grouped into antecedent and consequent phrases. These periods articulate large-scale sections, which outline a ternary formal design. Secondary parameters (dynamics, tempo markings, instrumental markings) further contribute to the identification of formal structures in Brouwer’s work.
76

A.A. Milne - When We Were Very Young : cycle éclectique de chansons pour enfants, chanté par des enfants

Jones Cadieux, Eric 08 1900 (has links)
Les fichiers qui accompagnent mon document on été réalisés avec les logiciels Microsoft Word et Finale. / When We Were Very Young est un recueil de poèmes écrit par A. A. Milne, que j’ai adapté en un cycle de chansons de styles diversifiés, pour le registre de la voix d'un enfant. Mon choix se justifie, d’une part, par le fait que ces poèmes n’ont jamais été adaptés dans leur intégralité et, d’autre part, par ma volonté de redonner à la génération d’aujourd’hui un héritage littéraire mis en une musique nouvelle. En travaillant les divers pastiches stylistiques, j’ai tenté d’élargir mes horizons musicaux, afin de trouver éventuellement ma propre voie. Ma musique est écrite pour être écoutée par un auditoire non averti, tout en visant le raffinement propre à une musique dite savante. La technique d’écriture employée se limite aux langages tonal et modal, de sorte à ne pas trop s’aventurer dans un discours harmonique trop complexe ou d’avant-garde. Par contre, là où je vois place à l’innovation, c’est sur le plan de la forme et de la texture. Tout en gardant un discours harmonique clair, ma démarche de compositeur cherche à briser le cadre rigide d’une forme de chanson à couplets et refrains, et de céder la place à une forme flexible, destinée à soutenir le détail de la prosodie, ainsi que les subtilités littéraires. De nos jours, la musique pour enfants se doit d’être presque simpliste, adaptée à un public estimé non intéressé par des sonorités plus riches et diversifiées. Bien que je conçoive que certains langages musicaux d’avant-garde sont effectivement trop complexes pour une oreille non entraînée, je crois tout de même possible de viser un niveau de composition qui, sans négliger l’auditoire, proposera à celui-ci des couleurs musicales nouvelles et intéressantes. / When We Were Very Young is a collection of poems by A.A. Milne that I have adapted to a stylistically diversified children's songbook. This choice was made for many reasons: first, this cycle has never been put to music in it's entirety; second, to bring our generation a literary heritage in song form. By working on different pastiches, I have attempted to broad my musical horizons, in order to eventually find my own voice. My music is designed to be enjoyed by a musically untrained audience, while aiming for refinement in texture and harmony. Therefore, the composition techniques used are bound to be limited to tonal or modal harmonies, to avoid overly complex progressions and find an innovative approach to texture and form. While keeping a clear harmonic language, my approach as a composer is to break the rigid form of a verse-chorus-verse type song and become more attentive to the prosody and the linguistic subtleties. Today, children's music is considered simple and adapted to a public deemed uninterested by rich and diversified textures. While I understand that many contemporary languages are too complex for an average listener, I believe it is still possible to aim at a compositional level that offers to its audience new and interesting colors.
77

HMM-based Vietnamese Text-To-Speech : Prosodic Phrasing Modeling, Corpus Design System Design, and Evaluation / Text-To-Speech à base de HMM (Hidden Markov Model) pour le vietnamien : modélisation de la segmentation prosodique, la conception du corpus, la conception du système, et l’évaluation perceptive

Nguyen, Thi Thu Trang 24 September 2015 (has links)
L’objectif de cette thèse est de concevoir et de construire, un système Text-To-Speech (TTS) haute qualité à base de HMM (Hidden Markov Model) pour le vietnamien, une langue tonale. Le système est appelé VTED (Vietnamese TExt-to-speech Development system). Au vu de la grande importance de tons lexicaux, un tonophone” – un allophones dans un contexte tonal – a été proposé comme nouvelle unité de la parole dans notre système de TTS. Un nouveau corpus d’entraînement, VDTS (Vietnamese Di-Tonophone Speech corpus), a été conçu à partir d’un grand texte brut pour une couverture de 100% de di-phones tonalisés (di-tonophones) en utilisant l’algorithme glouton. Un total d’environ 4000 phrases ont été enregistrées et pré-traitées comme corpus d’apprentissage de VTED.Dans la synthèse de la parole sur la base de HMM, bien que la durée de pause puisse être modélisée comme un phonème, l’apparition de pauses ne peut pas être prédite par HMM. Les niveaux de phrasé ne peuvent pas être complètement modélisés avec des caractéristiques de base. Cette recherche vise à obtenir un découpage automatique en groupes intonatifs au moyen des seuls indices de durée. Des blocs syntaxiques constitués de phrases syntaxiques avec un nombre borné de syllabes (n), ont été proposés pour prévoir allongement final (n = 6) et pause apparente (n = 10). Des améliorations pour allongement final ont été effectuées par des stratégies de regroupement des blocs syntaxiques simples. La qualité du modèle prédictive J48-arbre-décision pour l’apparence de pause à l’aide de blocs syntaxiques, combinée avec lien syntaxique et POS (Part-Of-Speech) dispose atteint un F-score de 81,4 % (Précision = 87,6 %, Recall = 75,9 %), beaucoup mieux que le modèle avec seulement POS (F-score=43,6%) ou un lien syntaxique (F-score=52,6%).L’architecture du système a été proposée sur la base de l’architecture HTS avec une extension d’une partie traitement du langage naturel pour le Vietnamien. L’apparence de pause a été prédit par le modèle proposé. Les caractéristiques contextuelles incluent les caractéristiques d’identité de “tonophones”, les caractéristiques de localisation, les caractéristiques liées à la tonalité, et les caractéristiques prosodiques (POS, allongement final, niveaux de rupture). Mary TTS a été choisi comme plateforme pour la mise en oeuvre de VTED. Dans le test MOS (Mean Opinion Score), le premier VTED, appris avec les anciens corpus et des fonctions de base, était plutôt bonne, 0,81 (sur une échelle MOS 5 points) plus élevé que le précédent système – HoaSung (lequel utilise la sélection de l’unité non-uniforme avec le même corpus) ; mais toujours 1,2-1,5 point de moins que le discours naturel. La qualité finale de VTED, avec le nouveau corpus et le modèle de phrasé prosodique, progresse d’environ 1,04 par rapport au premier VTED, et son écart avec le langage naturel a été nettement réduit. Dans le test d’intelligibilité, le VTED final a reçu un bon taux élevé de 95,4%, seulement 2,6% de moins que le discours naturel, et 18% plus élevé que le premier. Le taux d’erreur du premier VTED dans le test d’intelligibilité générale avec le carré latin test d’environ 6-12% plus élevé que le langage naturel selon des niveaux de syllabe, de ton ou par phonème. Le résultat final ne s’écarte de la parole naturelle que de 0,4-1,4%. / The thesis objective is to design and build a high quality Hidden Markov Model (HMM-)based Text-To-Speech (TTS) system for Vietnamese – a tonal language. The system is called VTED (Vietnamese TExt-tospeech Development system). In view of the great importance of lexical tones, a “tonophone” – an allophone in tonal context – was proposed as a new speech unit in our TTS system. A new training corpus, VDTS (Vietnamese Di-Tonophone Speech corpus), was designed for 100% coverage of di-phones in tonal contexts (i.e. di-tonophones) using the greedy algorithm from a huge raw text. A total of about 4,000 sentences of VDTS were recorded and pre-processed as a training corpus of VTED.In the HMM-based speech synthesis, although pause duration can be modeled as a phoneme, the appearanceof pauses cannot be predicted by HMMs. Lower phrasing levels above words may not be completely modeled with basic features. This research aimed at automatic prosodic phrasing for Vietnamese TTS using durational clues alone as it appeared too difficult to disentangle intonation from lexical tones. Syntactic blocks, i.e. syntactic phrases with a bounded number of syllables (n), were proposed for predicting final lengthening (n = 6) and pause appearance (n = 10). Improvements for final lengthening were done by some strategies of grouping single syntactic blocks. The quality of the predictive J48-decision-tree model for pause appearance using syntactic blocks combining with syntactic link and POS (Part-Of-Speech) features reached F-score of 81.4% Precision=87.6%, Recall=75.9%), much better than that of the model with only POS (F-score=43.6%)or syntactic link (F-score=52.6%) alone.The architecture of the system was proposed on the basis of the core architecture of HTS with an extension of a Natural Language Processing part for Vietnamese. Pause appearance was predicted by the proposed model. Contextual feature set included phone identity features, locational features, tone-related features, and prosodic features (i.e. POS, final lengthening, break levels). Mary TTS was chosen as a platform for implementing VTED. In the MOS (Mean Opinion Score) test, the first VTED, trained with the old corpus and basic features, was rather good, 0.81 (on a 5 point MOS scale) higher than the previous system – HoaSung (using the non-uniform unit selection with the same training corpus); but still 1.2-1.5 point lower than the natural speech. The quality of the final VTED, trained with the new corpus and prosodic phrasing model, progressed by about 1.04 compared to the first VTED, and its gap with the natural speech was much lessened. In the tone intelligibility test, the final VTED received a high correct rate of 95.4%, only 2.6% lower than the natural speech, and 18% higher than the initial one. The error rate of the first VTED in the intelligibility test with the Latin square design was about 6-12% higher than the natural speech depending on syllable, tone or phone levels. The final one diverged about only 0.4-1.4% from the natural speech.
78

Stravinsky e a música popular americana: Processos identitários, transposições hipertextuais e análise musical / Stravinsky and American popular music: identity processes, hypertextual transpositions and music analysis.

Araujo, Alexy Gaione Viegas de 07 April 2017 (has links)
Em observação à existência de obras de Stravinsky influenciadas pela música popular americana (incluindo Ragtime for Eleven Instruments, Preludium for Jazz Ensemble, Tango e Ebony Concerto) esta tese investiga processos identitários através dos quais o compositor fora possivelmente interpelado pela ideia do popular enquanto ponto de partida para situacionais possibilidades estéticas modernistas. Explora também tópicos da teoria hipertextual conforme proposta por Genette (1982), a fim de examinar a presença de transposições hipertextuais em empréstimos de ragtime realizados por Stravinsky. Por fim, realiza revisão de aspectos pertinentes a correntes teóricas no âmbito da relação entre alturas (SCHENKER, 1906, 1910, 1922, 1935; LERDAHL, 2001; STRAUS, 2014), de textura, densidade e movimento musical (BERRY, 1987), da repetição (FERRAZ, 1998) e da sucessão ordenada (HORLACHER, 2011); e da potencialidade projetiva (HASTY, 1997), com o propósito de apurar traços da articulação destas questões em processos composicionais de Stravinsky, com ênfase nas obras acima referidas. Os resultados obtidos por este trabalho apontam que os empréstimos de \"popular\" articulados por transposições hipertextuais atuam enquanto ponto de partida para criação de obras inéditas, as quais são estruturadas através de múltiplos centros de altura principal, níveis de prolongamento, blocos simultâneos e paralelismos. / Considering Stravinsky\'s American popular music inflected works (including Ragtime for Eleven Instruments, Preludium for Jazz Ensemble, Tango and Ebony Concerto), the present thesis aims to investigate identity processes through which Stravinsky was possibly challenged by the popular as a starting point for occasional modernist aesthetic possibilities. It also explores hypertextual theory topics as proposed by Genette (1982), in order to examine issues related to hypertextual transpositions in Stravinsky\'s ragtime borrowings. Finally, it carries out a review of theoretical trends relevant aspects, concearning pitch relations (SCHENKER, 1906, 1910, 1922, 1935 and LERDAHL, 2001); texture, density and musical movement (BERRY, 1987); repetition (FERRAZ, 1998); ordered succession (HORLACHER, 2011); and projective potentiality (HASTY, 1997), with the purpose of ascertaining traces of the articulation of these issues into Stravinsky\'s compositional processes. The results obtained by this work point out that the popular borrowings articulated by hypertextual transpositions act as a starting point for the creation of new works, which are structured through multiple pitch centers, levels of the basic space, simultaneous blocks and parallelism.
79

Música e discurso : das reflexões do círculo de Bakhtin aos contos de Machado de Assis /

Moro, Alexsandre Escorsi Messias. January 2010 (has links)
Orientador: Renata Maria Facuri Coelho Marchezan / Banca: Maria do Rosário Valencise Gregolin / Banca: Rinaldo Guariglia / Resumo: Nesta dissertação, buscamos compreender a produtividade das ideias do Círculo de Bakhtin no exame do diálogo e da interação entre o sistema de linguagem musical e o sistema de linguagem verbal. Analisamos formas de representação do discurso musical em contos de Machado de Assis (1839-1908). Para tanto, refletimos inicialmente sobre a relação de M. M. Bakhtin (1895-1975) com a música, o seu pensamento musical e sua importância teórica para a constituição da metodologia dialógica de análise da linguagem. Como são as ideias do Círculo sobre dialogismo, discurso direto, indireto e indireto livre, polifonia, modulação tonal e sinfonismo dialógico? A partir dessas ideias, como é possível analisar os alcances objetivos do pensamento musical de Machado de Assis em seus contos? Sendo assim, expomos e comentamos a estrutura, a organização e o funcionamento do material, da forma e do conteúdo do "som significativo" representado na linguagem verbal e musical. Por meio dessa concepção bakhtiniana, estudamos os alcances de continuidades e descontinuidades materiais, formais e semânticas do pensamento musical nas relações do sujeito com os elementos de linguagem musical e verbal. Desse modo, exploramos como o discurso musical de Machado de Assis foi percebido e tratado em perspectiva literária historiográfica e musicológica. Discorremos sobre como o sujeito, o tempo e o espaço aparecem refletidos, refratados e acomodados no diálogo da literatura com a música. Também examinamos como os temas do discurso musical machadiano são modulados no gênero conto e como eles são representados em esferas de atividades da cultura musical brasileira. Por fim, analisamos a posição dialógica do sujeito autor na enunciação do discurso musical e sua condução temática / Abstract: In this dissertation, we have researched the productivity of ideas from "Bakhtin's Circle" to the examination and understanding of "dialogue" and possible interactions between verbal and musical languages. By this way, we have analyzed Machado de Assis (1839-1908)'s musical discourse representation forms in his Brazilian short stories. So, at first, we have reflected about M. M. Bakhtin's musical language relationships answering what your musical thought is like and showing its theoretical importance to the constitution of dialogical methodology on language analysis. In other words, what the ideas from the Circle about dialogism, reported direct and indirect and free indirect speech, polyphony, tonal modulation and dialogical symphonism are like? Starting from those ideas, how is possible to analyze material objective reaches of the Machado de Assis's musical thought in his short stories? We have exposed and commented the material structure, the formal organization and the content semantic function of the "meaningful sound" represented in verbal and musical language. Through that bakhtinian conception, we have studied material reaches, formal and semantic continuities and descontinuities of musical thought in subject's relationships with musical and verbal language elements. We have explored how Machado de Assis's musical discourse was first perceived and treated by historiographic literary critic and musicology perspective. We have discoursed about how subject, time and space appear contemplated, refracted and suitable in literature's dialogue with music. We have also examined how musical themes from machadian literary discourse are modulated by short story genre and how they are represented in Brazilian culture spheres of musical activities. Finally, we have analyzed the subject author's dialogic position, his musical discourse enunciation and his thematic conduction / Mestre
80

Vestibular Evoked Myogenic Potentials Using Tonal Stimuli

Akin, Faith W., Murnane, Owen D., Medley, T. 01 January 2002 (has links)
No description available.

Page generated in 0.0774 seconds