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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.
231

An Investigation of Extrinsic Laryngeal Muscle Responses to Auditory Stimulation

Wallace, Jerry D. (Jerry Don) 08 1900 (has links)
The purpose of this study was to provide, through systematic investigation, empirical data to support or reject the assumption that auditory stimulation by discrete pitches evokes consistent muscle responses in the extrinsic laryngeal muscles. The study was an electromyographic investigation of specific upper and lower extrinsic laryngeal muscles as stimulated by two specific pitch stimuli. The responses were evoked by auditory stimulation, without vocalization. From these findings, it was concluded that a direct relationship exists between specific pitch stimuli and specific extrinsic laryngeal muscle responses. It was concluded that these responses likely exist in the general population.
232

Dynamics of Pitching Wave Energy Converter with Resonant U-Tank Power Extraction Device

Afonja, Adetoso J. 05 1900 (has links)
This research revolves around the concept design and theoretical validation of a new type of wave energy converter (WEC), comprising a pitching floater integrated with a resonant U-tank (RUT) and a Wells turbine as power take-off (PTO). Theoretical formulation of a fully coupled multi-body dynamic system, incorporating the thermodynamic processes of the RUT air chamber, its interaction with the PTO dynamics and their coupling with the floater is presented. Inaccuracies of the dynamic modeling of RUT based on Lloyd's low order model, which assumes constant hydrodynamic parameters irrespective of the frequency, are demonstrated by a series of high fidelity CFD simulations. These simulations are a systematic series of fully viscous turbulent simulations, using unsteady RANSE solvers, of the water sloshing at different frequencies of oscillation. Calibration of Lloyd’s model with CFD results evidenced that the RUT hydrodynamic parameters are not invariant to frequency. A numerical model was developed based on Simulink WEC-Sim libraries to solve the non-linear thermo-hydrodynamic equations of the device in time domain. For power assessment, parametric investigations are conducted by varying the main dimensions of the RUT and power RAOs were computed for each iteration. Performance in irregular sea state are assessed using a statistical approach with the assumption of linear wave theory. By superimposing spectrum energy density from two resource sites with RAO, mean annual energy production (MEAP) are computed. The predicted MEAP favorably compares with other existing devices, confirming the superior efficiency of the new proposed device over a larger range of incident wave frequency. / M.S. / This study present results of an investigation into a new type of wave energy converter which can be deployed in ocean and by its pitch response motion, it can harvest wave energy and convert it to electrical energy. This device consist of a floater, a U-tank (resonant U-tank) with sloshing water free to oscillate in response to the floater motion and a pneumatic turbine which produces power as air is forced to travel across it. The pneumatic turbine is used as the power take-off (PTO) device. A medium fidelity approach was taken to carry out this study by applying Lloyd’s model which describes the motion of the sloshing water in a resonant U-tank. Computational fluid dynamics (CFD) studies were carried out to calibrate the hydrodynamic parameters of the resonant U-tank as described by Lloyd and it was discovered that these parameters are frequency dependent, therefore Lloyd’s model was modelled to be frequency dependent. The mathematical formulation coupling the thermodynamic evolution of air in the resonant U-tank chamber, modified Lloyd’s sloshing water equation, floater dynamics and PTO were presented for the integrated system. These set of thermo-hydrodynamic equations were solved with a numerical model developed using MATLAB/Simulink WEC-Sim Libraries in time domain in other to capture the non-linearity arising from the coupled dynamics. To assess the annual energy productivity of the device, wave statistical data from two resource sites, Western Hawaii and Eel River were selected and used to carrying out computations on different iterations of the device by varying the tank’s main dimensions. This results were promising with the most performing device iteration yielding mean annual energy production of 579 MWh for Western Hawaii.
233

Absolutní sluch v teorii i praxi / Absolute Pitch: Theoretical Concept and Practical Issues

Bártová, Jitka January 2016 (has links)
The thesis aims at complex assessment of absolute pitch both theoretically and practically. It describes the functioning of ear and main issues related to processing of sound and tone height. In addition, it clarifies related terms stemming from musical psychology. Especially, it endeavours to identify causes of absolute pitch and factors which form it. The thesis surveys several phenomena connected with absolute pitch, for example with synesthesia, and with other aspects such as occurrence of absolute pitch among population. More practical part of research consists in a questionaire used for verification of hypotheses related to absolute pitch. The thesis uses not only the Czech but especially English written literature which has not yet been used in such a scope in the Czech musical research.
234

Absolutní sluch v teorii i praxi / Absolute Pitch: Theoretical Concept and Practical Issues

Bártová, Jitka January 2015 (has links)
The thesis aims at complex assessment of absolute pitch both theoretically and practically. It describes the functioning of ear and main issues related to processing of sound and tone height. In addition, it clarifies related terms stemming from musical psychology. Especially, it endeavours to identify causes of absolute pitch and factors which form it. The thesis surveys several phenomena connected with absolute pitch, for example with synesthesia, and with other aspects such as occurrence of absolute pitch among population. It uses not only the Czech but especially English written literature which has not yet been used in such a scope in the Czech musical research.
235

Návrh systému regulace vrtule stálých otáček / Design of regulation system for constant speed propeller

Líška, Lukáš January 2014 (has links)
This thesis deals with the design of electrical control for a constant speed propeller. The objective of this paper is to demonstrate the propeller governor design process on a case example of a DMP-3 propeller paired with a Rotax 912 ULS, using knowledge of flight mechanics, electrical engineering and automation. The scope of this thesis addresses the problems of propeller pitch control using an electrically driven linear actuator. In conclusion, this paper compares the benefits of the DMP-3 constant speed propeller, considering its use in existing airplanes within the UL-2 and CS-LSA category. Furthermore, it evaluates the capabilities of the proposed electronic governor, and outlines possibility of further development in this field.
236

Development of Pitch Perception Indexed By Infant Mismatch Responses

He, Chao 11 1900 (has links)
<p> Hearing provides a vital means for infants to discover their environment and communicate with their caregivers. Identifying and discriminating the pitch of sounds is critical for infants in order to acquire information from speech and music. Therefore, how infants process pitch is a fundamental question in research on auditory development. The focus of this dissertation is the use of auditory event related potentials (ERPs) derived from electroencephalogram (EEG) recordings to examine the maturation of pitch perception in early infancy. </p> <p> Pitch perception in adults has been extensively studied, but little is known about the development of pitch perception during early infancy. Infant mismatch responses (MMRs) are ERP components that are elicited by infrequent changes in auditory stimuli. MMR is a promising tool to study infant pitch perception because it can be elicited without attention or a behavioural response. However, previous studies on MMRs in infants have reported inconsistent results, some reporting frontally positive responses while others report frontally negative mismatch responses. In Chapter 2, we examined MMRs to simple pitch changes in infants between 2 and 4 months of age and found both types of infant MMRs are present, but the morphological distributions and developmental trajectories are different. In Chapter 3, we reported that both types of infant MMRs are affected similarly by the amplitude of pitch change but only the positive MMR becomes stronger when stimulus presentation rate increases, which suggests different neural mechanisms for the two types of infant MMRs. The studies reported in Chapter 4 found that only the negative MMR can be elicited readily by changes in pitch patterns, suggesting that it may be functionally similar to mismatch negativity (MMN) in adults. </p> <p> The experiments in Chapter 5 used MMR as the indication of whether infants automatically integrate the frequency components of a complex tone into a single pitch percept, even when the fundamental frequency component (corresponding to the pitch) is removed. Previous studies show that adult MMN is elicited by a pitch change in such tones missing the fundamental. Previous behavioural studies using a conditioned head tum method show that 7-month-olds also perceive pitch with tones missing the fundamental. The results of the present study indicate that infants as young as 4 months of age integrate components into a single pitch percept, but evidence for this in younger infants could not be found. </p> <p> In conclusion, the current dissertation established a promising procedure utilizing infant MMR to study infant pitch perception and contributed to the knowledge of early development of pitch perception by demonstrating dramatic changes in brain response to pitch in harmonic tones in infants between 2 and 4 months old, and to pitch in tones in infants missing the fundamental between 3 and 4 months old . </p> / Thesis / Doctor of Philosophy (PhD)
237

Les locuteurs d’une langue tonale sont-ils de meilleurs musiciens? Effet potentiel de la connaissance native d’une langue à tons sur la perception du contraste du pitch

Li, Na 11 1900 (has links)
Ce mémoire consiste à offre un survol des études neuropsychologiques et électrophysiologiques concernant l’interaction possible entre le traitement du langage et la musique. Le but principal est de déterminer les raisons possibles pour lesquelles des locuteurs d’une langue à tons auraient une meilleure capacité dans la perception du contraste du pitch en musique par rapport aux individus qui ont pour langue maternelle une langue à intonation. Dans un premier temps, nous discutons du traitement neuronal de la prosodie et de la musique, tentant de montrer le chevauchement du traitement cérébral des deux domaines. Ensuite, nous présentons des notions d’une langue tonale ainsi que le traitement neuronal des tons lexicaux. Après, nous discutons des effets de transfert de la capacité du traitement du pitch en linguistique et en musique, en nous focalisant sur l’influence de la connaissance native d’une langue tonale sur la perception musicale. Pour ce faire, l’encodage du pitch et la localisation hémisphérique du traitement des tons lexicaux et la musique serons discutés. / This thesis gives an overview of neuropsychological and electrophysiological studies about the possible interaction between the processing of language and music. Our main purpose is to examine the possible reasons for which tone language speakers have a better capacity in perceiving pitch contrast in music than native speakers of an intonational language. First, we discuss the neural processing of prosody and music, attempting to show an overlap between the two domains. Next, we present the concept of a tone langue and the neural processing of lexical tones. Afterwards, we discuss the transfer effects of the processing capacity of pitch in linguistic and music by focusing on the influence of a knowledge of a tone language on the musical perception. To do this, the encoding of pitch and the hemispheric specialization will be discussed.
238

Evolutionary and cognitive approaches to voice perception in humans : acoustic properties, personality and aesthetics

Knowles, Kristen January 2014 (has links)
Voices are used as a vehicle for language, and variation in the acoustic properties of voices also contains information about the speaker. Listeners use measurable qualities, such as pitch and formant traits, as cues to a speaker’s physical stature and attractiveness. Emotional states and personality characteristics are also judged from vocal stimuli. The research contained in this thesis examines vocal masculinity, aesthetics and personality, with an emphasis on the perception of prosocial traits including trustworthiness and cooperativeness. I will also explore themes which are more cognitive in nature, testing aspects of vocal stimuli which may affect trait attribution, memory and the ascription of identity. Chapters 2 and 3 explore systematic differences across vocal utterances, both in types of utterance using different classes of stimuli and across the time course of perception of the auditory signal. These chapters examine variation in acoustic measurements in addition to variation in listener attributions of commonly-judged speaker traits. The most important result from this work was that evaluations of attractiveness made using spontaneous speech correlated with those made using scripted speech recordings, but did not correlate with those made of the same persons using vowel stimuli. This calls into question the use of sustained vowel sounds for the attainment of ratings of subjective characteristics. Vowel and single-word stimuli are also quite short – while I found that attributions of masculinity were reliable at very short exposure times, more subjective traits like attractiveness and trustworthiness require a longer exposure time to elicit reliable attributions. I conclude with recommending an exposure time of at least 5 seconds in duration for such traits to be reliably assessed. Chapter 4 examines what vocal traits affect perceptions of pro-social qualities using both natural and manipulated variation in voices. While feminine pitch traits (F0 and F0-SD) were linked to cooperativeness ratings, masculine formant traits (Df and Pf) were also associated with cooperativeness. The relative importance of these traits as social signals is discussed. Chapter 5 questions what makes a voice memorable, and helps to differentiate between memory for individual voice identities and for the content which was spoken by administering recognition tests both within and across sensory modalities. While the data suggest that experimental manipulation of voice pitch did not influence memory for vocalised stimuli, attractive male voices were better remembered than unattractive voices, independent of pitch manipulation. Memory for cross-modal (textual) content was enhanced by raising the voice pitch of both male and female speakers. I link this pattern of results to the perceived dominance of voices which have been raised and lowered in pitch, and how this might impact how memories are formed and retained. Chapter 6 examines masculinity across visual and auditory sensory modalities using a cross-modal matching task. While participants were able to match voices to muted videos of both male and female speakers at rates above chance, and to static face images of men (but not women), differences in masculinity did not influence observers in their judgements, and voice and face masculinity were not correlated. These results are discussed in terms of the generally-accepted theory that masculinity and femininity in faces and voices communicate the same underlying genetic quality. The biological mechanisms by which vocal and facial masculinity could develop independently are speculated.
239

A Fourteen-Week Program for Teaching Beginning Music Reading Through Rhythmic Notation and Pitch Notation to Pre-School Children in Piano Classes

Ogilvy, Susan 05 1900 (has links)
The purpose of this study is to develop a fourteen-week program for teaching beginning music reading through rhythmic and pitch notation to pre-school children in piano classes. The historical background for the study discusses man's learning abilities in the group process in music education with the particular reference to class piano and its development and publications by leading authorities concerning class piano and rhythmic training in the classroom. The second chapter contains analyses and summaries of five selected texts pertinent to the study. The findings of research of the five selected texts serve as the groundwork for the development of the program which is contained in the third chapter.
240

Le chant basque monodique (1897-1990) : analyse musicologique comparée des sources écrites et musicales / Monodic basque singing (1897 - 1990) : comparative musicological analysis of written and musical sources

Hirigoyen Bidart, Marie 25 September 2012 (has links)
Le XXème siècle marque le début de l’étude musicologique sur le chant basque, concept apparu dans le courant du XIXème siècle. La plupart des recherches insistent sur les spécificités de cette pratique. A cette même époque, l’enregistrement de ce répertoire permet la constitution d’archives sonores. Pourtant, musicologues et collecteurs de sources sonores ne se rencontrent pas. Or, l’examen approfondi des études musicologiques publiées sur le chant basque amène à penser que les caractéristiques musicales attribuées à cette pratique tout au long du XXème siècle ne sont pas toutes pertinentes, que ce soit dans les termes employés ou dans la conception même de la musique. Elles renseignent parfois plus sur les auteurs et le contexte d’écriture de l’ouvrage/ article que sur la musique elle-même. Ces descriptionspeuvent de ce fait être nuancées à la lumière de nouvelles analyses. Une comparaison diachronique et synchronique de sources écrites et musicales de la fin du XIXème siècle à la fin du XXème siècle permet d’une part d’observer le lien entre ce qui est « dit » sur le sujet du point de vue musicologique et ce que nous pouvons en entendre, et d’autre part de repérer les caractéristiques musicales communes qui se dégagent de l’ensemble. Nous formulons l’hypothèse qu’il existe dans le chant basque monodique, non des caractéristiques musicales intrinsèques, mais des éléments musicaux mobiles, variés, des « indices », notamment du point de vue de la hauteur, qui peuvent être observés grâce à des outils d’analyse modernes. / The XXth century marks the beginning of the musicological study of the Basque singing, a concept appeared during the course of the XIXth century. Most of these researchs insist on the specificities of such a practice. At the same time, the recording of this repertory allows the setting up of sound archives. Nevertheless, musicologists and collectors of the sound sources do not meet. However, a thorough examination of the musicology studies published about the Basque singing leads to think that the musical characteristics ascribed to this practice throughout the XXth century are not all relevant whether concerning the terms being used or the conception of the very music. They often inform more on the authors and the context of the writing of the work/article than on the music itself. These descriptions may then be qualified in the light of new analyses. A diachronic and synchronic comparison of the written and musical sources from the late XIXth century to the end of the XXth allows us, on the one hand, to observe the link between what is “said” on the topic from the musicology point of view and what we can hear, and on the other hand to spot the common musical characteristics emerging from the whole.We formulate the hypothesis that the monodic Basque singing does not present any intrinsic musical characteristics. Rather, we observe mobile and diverse musical elements, kinds of “clues”, especially as far as pitch is concerned, that can be observed thanks to modern analysis tools.

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