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Baldwin, Carol May. "The voice of emotion: Acoustic properties of six emotional expressions." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184337.
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Studies in the perceptual identification of emotional states suggested that listeners seemed to depend on a limited set of vocal cues to distinguish among emotions. Linguistics and speech science literatures have indicated that this small set of cues included intensity, fundamental frequency, and temporal properties such as speech rate and duration. Little research has been done, however, to validate these cues in the production of emotional speech, or to determine if specific dimensions of each cue are associated with the production of a particular emotion for a variety of speakers. This study addressed deficiencies in understanding of the acoustical properties of duration and intensity as components of emotional speech by means of speech science instrumentation. Acoustic data were conveyed in a brief sentence spoken by twelve English speaking adult male and female subjects, half with dramatic training, and half without such training. Simulated expressions included: happiness, surprise, sadness, fear, anger, and disgust. The study demonstrated that the acoustic property of mean intensity served as an important cue for a vocal taxonomy. Overall duration was rejected as an element for a general taxonomy due to interactions involving gender and role. Findings suggested a gender-related taxonomy, however, based on differences in the ways in which men and women use the duration cue in their emotional expressions. Results also indicated that speaker training may influence greater use of the duration cue in expressions of emotion, particularly for male actors. Discussion of these results provided linkages to (1) practical management of emotional interactions in clinical and interpersonal environments, (2) implications for differences in the ways in which males and females may be socialized to express emotions, and (3) guidelines for future perceptual studies of emotional sensitivity.
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Knowles, Kristen. "Evolutionary and cognitive approaches to voice perception in humans : acoustic properties, personality and aesthetics." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/21784.
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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.
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Krull, Diana. "Acoustic Properties as Predictors of Perceptual Responses : a Study of Swedish Voiced Stops." Doctoral thesis, Stockholms universitet, Institutionen för lingvistik, 1988. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-40213.
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In speech recognition algorithms and certain theories of speech perception the interpretation of the signal is based on " distance scores " for comparisons of the signal with stored references; in these theories, perception is seen as a product of stimulus and experience. The aim of the present thesis is to evaluate such distance measures by investigating the perceptual confusions of the Swedish voiced stops [b,d,q,g] in systematically varied fragments of vowel-consonantvowel stimuli providing 25 vowel contexts for each consonant. To what extent can perceptual identifications be accounted for in terms of the acoustic properties of the stimuli? Short stimulus segments following stop release, chosen to elicit perceptual confusions, constituted the main material for this investigation. The resulting confusions were shown to form a regular pattern depending mainly on the acute/grave dimension of the following vowel. The acoustic distances calculated were based partly on formant frequencies at the consonant-vowel boundary, partly on filter-band spectra. B oth models provided distance measures which revealed regular patterns related in their essentials to the confusions. However, the predictive capacity of both models was improved by including the dynamic properties of the stimuli in the distance measures. The highest correlation between predicted and observed percent confusions, r=.85, was obtained with the fOlmant-based model. The asymmetries in the listeners' confusions were also shown to be predictable given acoustic data on the following vowel and were included in the calculations.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
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Schoenstgen, Jean. "Acoustic features of modal voice." Doctoral thesis, Universite Libre de Bruxelles, 2003. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211340.
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Chang, Wing-yin Maureen. "Perceptual and acoustic differences between aging voice and dysphonic voice." Click to view the E-thesis via HKUTO, 2001. http://sunzi.lib.hku.hk/hkuto/record/B36207810.
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Thesis (B.Sc)--University of Hong Kong, 2001."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, May 4, 2001. Also available in print.
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Sari, Hayri. "Underwater acoustic voice communications using digital techniques." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/13854.
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An underwater acoustic voice communications system can provide a vital communication link between divers and surface supervisors. There are numerous situations in which a communication system is essential. In the event of an emergency, a diver's life may depend on fast and effective action at the surface. The design and implementation of a digital underwater acoustic voice communication system using a digital signal processor (DSP) is described. The use of a DSP enables the adoption of computationally complex speech signal processing algorithms and the transmission and reception of digital data through an underwater acoustic channel. The system is capable of operating in both transmitting and receiving modes by using a mode selection scheme. During the transmission mode, by using linear predictive coding (LPC), the speech signal is compressed whilst transmitting the compressed data in digital pulse position modulation (DPPM) format at a transmission rate of 2400 bps. At the receiver, a maximum energy detection technique is employed to identify the pulse position, enabling correct data decoding which in turn allows the speech signal to be reconstructed. The advantage of the system is to introduce advances in digital technology to underwater acoustic voice communications and update the present analogue systems employing AM and SSB modulation. Since the DSP-based system is designed in modular sections, the hardware and software can be modified if the performance of the system is inadequate. The communication system was tested successfully in a large indoor tank to simulate the effect of a short and very shallow underwater channel with severe multipath reverberation. The other objective of this study was to improve the quality of the transmitted speech signal. When the system is used by SCUBA divers, the speech signal is produced in a mask with a high pressure air environment, and bubble and breathing noise affect the speech clarity. Breathing noise is cancelled by implementing a combination of zero crossing rate and energy detection. In order to cancel bubble noise spectral subtraction and adaptive noise cancelling algorithms were simulated; the latter was found to be superior and was adopted for the current system.
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Wheeler, Karen Michelle. "Predicability of the Voice Handicap Index relative to acoustic measures of voice." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000823.
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Li, Lai-ching Gina. "Voice quality of Cantonese tones an acoustic study /." Click to view the E-thesis via HKUTO, 1997. http://sunzi.lib.hku.hk/hkuto/record/B3620948X.
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Thesis (B.Sc)--University of Hong Kong, 1997."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, April 30, 1997." Also available in print.
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Suiter, Wendy. "Text manipulation voice with audio or acoustic augmentation /." Access electronically, 2007. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20080228.103431/index.html.
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Rockwell, Patricia Ann. "The voice of deceit: Comparing acoustic and perceptual data." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186929.
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This study examined the nature of deceptive vocal behavior in interactive situations. It compared those vocal features of deception that can be measured by acoustic equipment with those vocal features of deception that can be measured perceptually by human coders. As deception researchers traditionally measure vocal behavior with either acoustic or perceptual methods, it is uncertain what correspondence, if any, exists between these two methods. This study attempted to determine this correspondence. Deceptive interactions from an earlier study (Buller, Burgoon, Buslig & Roiger, 1993; Burgoon, Buller, Ebesu, White, and Rockwell, 1994) were used to conduct a detailed analysis of vocal features of deceptive speech. The vocal samples were analyzed perceptually and acoustically. Results indicated moderate correlations between some acoustic and perceptual variables, with neither measurement type proving conclusively superior to the other in discriminating between truth and deception. Of three categories examined (time, pitch, and intensity), the time variables of shorter message length, longer response latencies, slower tempo, and less fluency best discriminated between truthful and deceptive statements. Other variables that discriminated truth from deceit were increased intensity range, increased pitch level and variance, and less pleasant vocal quality. Analyses of deception type showed that fabricated deceptions were louder and lower pitched than equivocal deceptions. An analysis of deception planning, showed that planned deceptions exhibited more fluency, a lower pitch level, and less pitch variance than unplanned deceptions. An examination of correlations between deceiver/receiver evaluations of deceiver honesty and deceiver vocal behaviors showed moderate correlations occurred between these evaluations and length of response latencies, pitch level, pitch range, and pitch variance. In general, these findings provide further confirmation of Interpersonal Deception Theory.
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Malyska, Nicolas 1977. "Automatic voice disorder recognition using acoustic amplitude modulation features." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30092.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 114-117).
An automatic dysphonia recognition system is designed that exploits amplitude modulations (AM) in voice using biologically-inspired models. This system recognizes general dysphonia and four subclasses: hyperfunction, A-P squeezing, paralysis, and vocal fold lesions. The models developed represent processing in the auditory system at the level of the cochlea, auditory nerve, and inferior colliculus. Recognition experiments using dysphonic sentence data obtained from the Kay Elemetrics Disordered Voice Database suggest that our system provides complementary information to state-of-the-art mel-cepstral features. A model for analyzing AM in dysphonic speech is also developed from a traditional communications engineering perspective. Through a case study of seven disordered voices, we show that different AM patterns occur in different frequency bands. This perspective challenges current dysphonia analysis methods that analyze AM in the time-domain signal.
by Nicolas Malyska.
S.M.
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Tangsangiumvisai, Nisachon. "Algorithms and structures for stereophonic acoustic echo cancellation." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251753.
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ISHIKAWA, KEIKO. "VOCAL FUNCTION EXERCISES (VFE): ACOUSTIC AND PHYSIOLOGIC EXAMINATION OF SUSTAINED /O/ WITH BUZZ." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1148316914.
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Pandit, Medha. "Voice and lip based speaker verification." Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/915/.
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Chen, Wu-Nan. "Multiple microphone voice activity detection and adaptive noise cancellation." Thesis, University of the West of Scotland, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365083.
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Nelson, Wendy Jill. "Acoustic, physiologic, and aerodynamic effects of the clinical stimulation technique "tongue protrusion/i/" /." abstract and full text PDF (UNR users only), 1998. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1389835.
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Mautner, Helene. "A Cross-System Instrumental Voice Profile of the Aging Voice: With Considerations of Jaw Posture Effects." Thesis, University of Canterbury. Communication Disorders, 2011. http://hdl.handle.net/10092/5183.
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Purpose: An open mouth approach is used in voice therapy for enhancing speech and voice production and relaxing the laryngeal musculature. The acoustic and physiological consequences of an open jaw posture, however, have not been clearly understood due to a paucity of cross-system studies taking the age effect into consideration. The major aims of this study are twofold (1) to examine if the geriatric voice may be improved using an “open jaw” posture and (2) if an aging effect on the voice of normal healthy adults can be detected through acoustic and physiological measures
Method: The main part of this study involved simultaneous multi-channel voice recordings obtained from 85 healthy adults aged between 38 and 93 years. A convenience sampling strategy was used to recruit at least five females and five males in each of four age groups, 35-59 years (35+), 60-69 (60+), 70-79 (70+), and above 80 (80+). For simultaneous acoustic, electroglottographic (EGG), and jaw displacement recordings, participants were asked to perform two tasks which included a sustained vowel task and a sentence production task. The sustained vowel task involved sustaining the vowel /a/ in five different conditions, an isolated vowel /a/ produced at normal, low, and high pitch levels and the vowel /a/ initiated with a consonant (/m/ and /h/). The sentence production task involved production of the sentence 'We saw two cars,' containing the vowels /i, ɔ, u, a/. For simultaneous airflow-EGG recordings, participants were asked to sustain the vowel /a/ at normal pitch. For simultaneous airflow-air pressure-EGG recordings, participants were asked to repeat /pa/ five times in one breath. Participants were asked to perform all of the tasks using two jaw postures (normal and open). A series of univariate analysis of variances were used to identify instrumental measures sensitive for discriminating between the four age groups and the two jaw postures. A follow-up perceptual study was conducted to determine the effect of an open jaw posture on vowel intelligibility and voice clarity. A quota sampling strategy was used to recruit 40 normal hearing participants, including 20 females (age range = 18-42 years, mean = 25.3, SD = 7.9) and 20 males (age range = 18-47, mean = 23.6, SD = 6.7). These listeners were presented with vowels segmented from the sentences recorded in the first experiment and asked to perform a vowel identification and a voice clarity discrimination task. The vowel samples were taken from 40 speakers, with five females and five males in each of the four age groups (35+, 60+, 70+, and 80+). The percentages of correct vowel identification for voices produced with normal and open jaw postures were compared. The percentages of vowels judged as 'clearer' in a normal-open jaw contrast pairs were also calculated for comparison.
Results: Significant age group effects were found in this study for both genders on fundamental frequency (F0), voice onset time (VOT) (/ka/), open quotient (OQ), and speed quotient (SQ), with additional age differences detected for females on %jitter, %shimmer, signal-to-noise ratio (SNR), and the second formant frequency (F2), and for males a significant age group effect was found on VOT (/tu/). Results for both females and males revealed significant open jaw posture effects on F0, F2, VOT (/ka/), MFR, SPL and vowel space area. In addition, for females significant posture effects were found on F1, subglottal pressure and the H1-H2 amplitude difference, and for males, significant posture effects were found on %jitter and VOT-/tu/. Results from the follow-up perceptual study revealed that an open jaw posture was associated with better vowel identification and better voice clarity.
Conclusions: A selection of instrumental measures was shown to be useful for detecting voice changes due to aging. Instrumental and perceptual evidence was found that an open jaw posture was associated with positive changes in vocal behaviours, including improved phonatory stability, vocal power, and voice clarity.
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Huang, Weichun. "Acoustic properties of natural materials." Thesis, Le Mans, 2018. http://www.theses.fr/2018LEMA1031/document.
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Dans cette thèse, nous étudions un métamatériau inspiré de la paille de blé pour l'absorption parfaite du son. Une botte de paille estidéalisée comme un milieu poreux anisotrope, composé d’un arrangement périodique très concentré de tubes creux cylindriques. L’approche théorique de ce métamatériau repose sur l'homogénéisation asymptotique à deux échelles d'un réseau perméable de résonateursparfaitement rigides dont la physique est enrichi par des résonances internes. Les principales caractéristiques de ce milieu poreux sont lacompressibilité effective négative autour de la résonance du tube et la réduction drastique de la vitesse de propagation du son (slowsound) à très basse fréquence. Une configuration optimale est conçue, basée sur la condition de couplage critique, pour laquelle la fuited’énergie du système résonnant ouvert est parfaitement compensée par les pertes intrinsèques induites par les pertes viscothermiques.Des mesures en tube à impédance sont effectuées sur des échantillons fabriqués par impression additive pour valider les résultatsthéoriques. Nous montrons que ce métamatériau est un absorbeur sub-longueur d'onde capable d’une absorption parfaite à très bassefréquence et d'introduire une quasi-bande interdite autour de la résonance du tube. De plus, la nature anisotrope de ce matériau conduit àune absorption globalement élevée à basse fréquence et ce pour toutes les incidences. Cette étude offre la possibilité de concevoir unabsorbeur acoustique sélectif en angle et en fréquence. Pour conclure, les résultats de cette thèse montrent que la paille est un boncandidat pour une absorption acoustique parfaiteStraw-inspired metamaterials for sound absorption are investigated in this Thesis. A straw stack is idealized as a highly concentratedresonant anisotropic porous medium constituted of a periodic arrangement of densely packed cylindrical hollow tubes. The approach tothis metamaterial relies on the two-scale asymptotic homogenization of a permeable array of perfectly rigid resonators, where the physicsis further enriched by tailoring inner resonances. The main features of such sound absorbing medium are the possibility for the effectivecompressibility to become negative around the tube resonance and the drastic reduction of the effective sound speed (slow sound) at verylow frequency in the system. Moreover, an optimal configuration for sound absorption is designed, based on the critical couplingcondition, in which the energy leakage out of the open resonant system is perfectly compensated by the intrinsic losses induced by thevisco-thermal losses both in the anisotropic matrix and in the resonators. Impedance tube measurements are performed on 3-D printedsamples with controlled parameters to validate the theoretical results. This metamaterial is a sub-wavelength absorber that can achievetotal absorption at a very low frequency and possesses a quasi-band-gap around the tube resonance. Furthermore, the anisotropic nature ofthe configuration gives rise to high absorption at low-frequency range for all incidences and diffuse field excitation. It paves the way tothe design of angular and frequency selective sound absorber. To conclude, the results of this Thesis show that straw is a good candidatefor perfect sound absorption
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Ambróz, Richard. "Analysis of Powertrain Acoustic Properties." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-234137.
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Dizertačná práca rieši problematiku analýzy akustických vlastností pohonných jednotiek. V úvodnej časti je teoretický rozbor fyzikálnych princípov vibrácií a hluku a prehľad súčasného stavu riešenia problematiky v oblasti návrhu pohonných jednotiek. Vlastná časť práce popisuje konštrukčný návrh elektrodynamického budiča vibrácií, návrh hodnotenia výsledkov merania a taktiež spôsob spracovania výsledkov. Akustické vlastnosti sú hodnotené pomocou normálových rýchlostí kmitania povrchu. V závere práce sú prezentované ukážky využitia metódy v praktických príkladoch spojených s návrhom pohonnej jednotky. Celé riešenie predstavuje ucelený spôsob analýzy vhodný pre rýchle hodnotenie vplyvu konštrukčných úprav na akustické vlastnosti.
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Bozzette, Maryann. "Premature infant responses to taped maternal voice /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/7220.
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Lee, Matthew E. "Acoustic Models for the Analysis and Synthesis of the Singing Voice." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6859.
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Throughout our history, the singing voice has been a fundamental tool for musical expression. While analysis and digital synthesis techniques have been developed for normal speech, few models and techniques have been focused on the singing voice. The central theme of this research is the development of models aimed at the characterization and synthesis of the singing voice. First, a spectral model is presented in which asymmetric generalized Gaussian functions are used to represent the formant structure of a singing voice in a flexible manner. Efficient methods for searching the parameter space are investigated and challenges associated with smooth parameter trajectories are discussed. Next a model for glottal characterization is introduced by first presenting an analysis of the relationship between measurable spectral qualities of the glottal waveform and perceptually relevant time-domain parameters. A mathematical derivation of this relationship is presented and is extended as a method for parameter estimation. These concepts are then used to outline a procedure for modifying glottal textures and qualities in the frequency domain.
By combining these models with the Analysis-by-Synthesis/Overlap-Add sinusoidal model, the spectral and glottal models are shown to be capable of characterizing the singing voice according to traits such as level of training and registration. An application is presented in which these parameterizations are used to implement a system for singing voice enhancement. Subjective listening tests were conducted in which listeners showed an overall preference for outputs produced by the proposed enhancement system over both unmodified voices and voices enhanced with
competitive methods.
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Fahlgren, Anton. "Combining Acoustic Echo Cancellation and Voice Activity Detection in Social Robotics." Thesis, KTH, Matematik (Avd.), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-248001.
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This thesis is partly a theoretical introduction to some basic concepts of signal processing such as the Fourier transform, linear time invariant systems and spectral analysis of random signals, both in the continuous and discrete setting. A second part is devoted to theory and applications of echo cancellation and voice activity detection in so called social robotics. Existing methods are presented along with new specialized methods and both are later evaluated.Vi ger en teoretisk introduktion till grundläggande koncept inom kontinuerlig och diskret signalhantering som Fourier-transformen, linjära tidsinvarianta system och spektralanalys av slumpsignaler. En andra del behandla teori och tillämpningar för ekokansellering och röstdetektion i så kallad social robotik. Existerande metoder presenteras tillsammans med nya specialiserade metoder och samtliga utvärderas
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Howell, Henry R. G. "Inferring bottom acoustic properties from AN /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA384490.
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Thesis (M.S. in Physical Oceanography) Naval Postgraduate School, Sept. 2000."September 2000." Thesis advisor(s): Bourke, Robert H.; Wilson, James H. Includes bibliographical references (p. 89-92). Also available online.
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Gardner, Trevor Noel. "The acoustic properties of gassy soil." Thesis, University of Oxford, 1988. http://ora.ox.ac.uk/objects/uuid:1fe2a2d0-a2e3-4f8d-bb37-3db2e1505939.
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Compression wave sound speed and attenuation measurements are made in the laboratory over frequencies in the range from 10 kHz to 1 MHz on samples of estuarine silty clay that have been provided with varying amounts of uniformly distributed gas bubbles. The soil can be idealised as a two phase material of spherical gas pockets within a matrix of saturated soil, where the pocket sizes are in the range from 100 to 2000 μm diameter. It is shown that the acoustic response of this soil is dominated by the gas fraction and bubble size of the gas phase, and by the elastic moduli of the matrix phase, within the frequency range that causes bubbles to pulsate radially (resonate). Below this range, it is shown that the sound speed response is not significantly affected by bubble size, except close to the saturated soil condition. The gas fraction and bubble size distribution of each sample is measured and used, with values of the appropriate elastic moduli from the literature, to provide curves from current theory. The theory is evaluated in comparison to the experiment results, and proposals are made, which may provide the basis for the prediction of the gas fraction and bubble sizes of sea-bed sediments that are suspected of containing gas. Such a process would involve the use of an acoustic probe to obtain in situ sound speed and attenuation measurements using the signal analysis techniques developed in this study.
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Vasilic, Ana. "Homogenizing acoustic properties of cancellous bone." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 134 p, 2009. http://proquest.umi.com/pqdweb?did=1885756531&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Kulikov, Vladimir. "Voicing and voice assimilation in Russian stops." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3327.
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The main objective of this thesis is to investigate acoustic cues for the voicing contrast in stops in Russian for effects of speaking rate and phonetic environment. Although the laryngeal contrast in Russian is assumed to be a [voice] contrast, very few experimental studies have looked at the acoustic properties of Russian voiced and voiceless stops. Most claims about acoustic properties of stops and phonological processes that affect them (voice assimilation and final devoicing) have been made based on impressionistic transcriptions. The present study provides evidence that (1) voicing in voiced stops is affected by speaking rate manipulation, (2) stops in Russian retain underlying voicing contrast in presonorant position and voice assimilation occurs only in obstruent clusters, and (3) phonological processes of voice assimilation and final devoicing do not result in complete neutralization.
The target of the investigation is voiced and voiceless intervocalic stops, stops in clusters, and final stops in different prosodic positions within a word and at the phrase level. The acoustic cues to voicing (duration of voicing, stop closure duration, vowel duration, f0, and F1) were measured from the production data of 14 monolingual speakers of Russian recorded in Russia. Speakers produced words and phrases with target stops in three speaking rate conditions: list reading, slow rate and fast rate. The data were analyzed in 5 blocks focusing on (1) word-internal stops, (2) voice assimilation in stops in prepositions, (3) cases of so-called "sonorant transparency", (4) voice assimilation in stops before /v/, and (5) voicing processes across a word boundary.
The results of the study present a challenge to the widely-held assumption that phonological processes precede phonetic processes at the phonology-phonetics interface. It is shown that the underlying contrast leaves traces on assimilated and devoiced stops. To account for the findings, a phonology-phonetics interface that allows interaction between the modules is required. In addition, the results show that temporal cues are affected by speaking rate manipulation, but the effect of rate on voicing is found only in voiced stops. Duration of voicing and VOT in voiceless stops are not affected by speaking rate. The results also show that no effect of C2 is obtained on voicing in C1 stops in in obstruent-sonorant-obstruent clusters, thus no "phonological sonorant transparency to voice assimilation" is found in Russian. Rather, the study provides evidence that there is variation in production of voicing in stops in prepositions, and that voice assimilation in stops before /v/ followed by a voiced obstruent is optional for some speakers.
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Foote, Alexander Gavin. "Contemporary commercial music (CCM) singers| Lifestyle choices and acoustic measures of voice." Thesis, State University of New York at Buffalo, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1594707.
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Contemporary commercial music (CCM) singers may be at a high risk for voice damage due to their increased vocal demands and the chronic exposure to chemical irritants associated with unhealthy lifestyle choices. Continuous mechanical damage, confounded with chemical trauma, has detrimental effects on the biomechanical properties of the vocal folds. Prior research on CCM singers has been limited, with efforts focused on physiologic aspects of voice production. The objective of the study was to report on the lifestyle choices of CCM singers and evaluate their vocal abilities according to healthy vs. unhealthy profile status via acoustic analyses as well as auditory perceptual assessments. The second objective was to evaluate if there were differences in lung volume associated with healthy vs. unhealthy lifestyle profiles.
Thirteen CCM singers participated in the study where they were assigned to either a healthy or unhealthy lifestyle vocal profile. Acoustic analyses of sound pressure level (SPL), signal-to-noise ratio (SNR), fundamental frequency (F0), and jitter/shimmer were collected during a prolonged singing /i/ in isolation as well as a singing /i/ in context of the “Star Spangled Banner” at three different vocal intensities (low, comfortable, high). Lung volume was recorded via a vital capacity maneuver. Voice recordings were then rated via an auditory perceptual assessment (CAPE-V). Results were compared with a Wilcoxon rank-sum test.
Differences with regard to group trends were observed across all dependent measures. SNR median values for unhealthy singers were significantly lower in both singing tasks during low vocal intensity (p<0.05), with differences approaching significance found during prolonged singing /i/ in isolation at comfortable vocal intensity (p<0.10). F0 analysis noted significantly lower median values for unhealthy singers during isolated /i/ productions at low vocal intensity (p<0.05). Jitter analysis among unhealthy singers showed significantly higher median values during isolated /i/ productions at comfortable vocal intensity (p<0.05), with differences approaching significance found during singing /i/ in context at low vocal intensity (p<0.10). Shimmer analysis among unhealthy singers showed significantly higher median values during isolated /i/ productions at low and comfortable vocal intensity (p<0.05), with differences approaching significance found during singing /i/ in context at low vocal intensity (p<0.10). Unhealthy singers showed lower vital capacity as compared to healthy singers, however results were nonsignificant (p>0.05). Auditory perceptual assessment of voice was perceived to be essentially normal for all participants regardless of healthy versus unhealthy profile status.
The findings provide a descriptive profile of contemporary commercial music singers and contribute to the existing literature on the harmful effects of exposure to cigarette smoke on voice production. Unhealthy singers displayed significant acoustic differences most often observed in low vocal intensity conditions, which suggest a decreased vocal ability. This may be explained by their repeated exposure to chemical irritants (i.e. cigarette smoke) and possible phonotrauma, causing changes in the biomechanical properties of the vocal folds. Given the disparity between acoustic measures and auditory perceptual assessment, it was concluded that the biomechanical changes might be in the early onset and suggest future voice difficulties.
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Härkönen, P. (Pauli). "The Acoustic Voice Quality Index äänihuulihalvauspotilaiden ja spasmodisten dysfoniapotilaiden äänen laadun mittarina." Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201802081193.
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Tämän pro gradu -tutkielman tarkoituksena oli selvittää tietokonepohjaisen objektiivisen The Acoustic Voice Quality Index -mittarin (AVQI) soveltuvuutta suomenkielisten puhujien äänen laadun mittaukseen. Tutkimuksessa kysyttiin, pystyykö mittari erottamaan terveet äänet äänihäiriöistä. Tutkitut häiriöryhmät olivat äänihuulihalvaus ja spasmodinen dysfonia. Myös äänihäiriöryhmien väliltä etsittiin eroja AVQI-mittauksilla.
Tähän tutkimukseen osallistui yhteensä 95 tutkittavaa: äänihuulihalvauksesta kärsivät (n = 20), spasmodisesta dysfoniasta kärsivät (n = 19) ja terveääniset puhujat (n = 56). Kaikki olivat äidinkieleltään suomea puhuvia aikuisia. Äänihäiriöistä kärsivät puhujat olivat Tampereen yliopistollisen sairaalan foniatrian poliklinikan potilaita, joilla oli oltava diagnosoituna oikea äänihäiriö. Tutkimuksen aineistona käytetyt äänitykset kerättiin terveäänisten osalta Tampereen yliopistolla ja äänihäiriöstä kärsivien osalta TAYS:n foniatrisella poliklinikalla, joissa kummassakin oli käytössä sama äänityslaitteisto. Kultakin puhujalta kerättiin kolme pidennetyn vokaalin näytettä sekä luentanäyte. Äänitiedostot analysoitiin AVQI-skriptillä Praat-puheanalyysiohjelmassa. Tulokseksi saadut AVQI-arvot muodostuivat painotetusti kuudesta eri äänenlaatua mittaavasta akustisesta parametrista.
Tässä tutkimuksessa löydettiin tilastollisesti erittäin merkitsevää eroa verrattaessa terveäänisten puhujien AVQI-arvojen keskiarvoa kumman tahansa äänihäiriöryhmän keskiarvoon. Myös kaikkien paitsi yhden AVQI:n osaparametrin keskiarvojen väliltä löydettiin tilastollisesti erittäin merkitsevät erot verrattaessa terveäänisten ryhmää äänihäiriöryhmiin. Ainoastaan piirteessä tilt of trendline through spectrum (spektrin regressiosuoran kulma) ei tilastollista merkitsevyyttä löytynyt kontrolliryhmän ja spasmodisesta dysfoniasta kärsivien väliltä. Piirre kuitenkin erotti ainoana piirteenä äänihuulihalvauksen ja spasmodisen dysfonian toisistaan tilastollisesti merkitsevästi.
Tutkimus antaa näyttöä siitä, että AVQI on tehokas erottamaan häiriintyneen äänen häiriöttömästä suomenkielisilläkin puhujilla. Tuloksia voidaan pitää suuntaa antavina, eivätkä ne ole automaattisesti yleistettävissä kaikkiin äänihäiriöryhmiin. Varmuutta ei saatu siitä, erottaako AVQI äänihäiriöitä laadullisesti toisistaan.
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Zawawi, Nor Shahrina. "Measuring voluntary cough and its relationship to the perception of voice." Thesis, University of Canterbury. Department of Communication Disorders, 2010. http://hdl.handle.net/10092/3923.
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Cough is a motor act of the laryngeal and respiratory systems. Features of coughing have been considered in the examination of respiratory, swallowing and voice disorders. Although some voice disorders have been linked to excessive coughing, the precise relationship between cough and voice remains unknown. The present study examined the acoustic features of cough across sex and age; and its relationship to the perception of voice production. A total of 30 cough samples and 30 voice samples were collected from 15 healthy females and 15 healthy males; ranging from young age (17-25 years old), middle-aged (30-45 years old) and older-age (60 years old & above). Coughs containing three distinct phases were submitted to an acoustic analysis of the long-term average spectrum (LTAS) and cough duration. Both cough and voice samples were examined perceptually by a group of 20 speech-language pathologists. Results found a distinct three-phase pattern of cough that was remarkably stable across sex and age. Significant differences were found in the duration of each phase of cough. Perception of cough was not significantly related to acoustic features of cough. Perceptual judgment of sex was comparable for both cough and voice samples. However, the accuracy of age recognition was higher for voice samples compared to cough samples. In addition, voice was judged to be healthier and stronger than cough. Overall, the results partially support the previous acoustic findings on cough. A strong relationship between the acoustics of cough and the perception of cough was not evident. Listeners judged voice differently from cough, except for sex recognition. The clinical implications of the findings are discussed.
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Zeller, Brett Dale. "Acoustic measurement of adhesive/adherend interlayer properties." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417261.
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Kristoffersson, Jesper. "Acoustic properties of porous materialsused in silencers." Thesis, KTH, Farkost och flyg, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143497.
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The aim of this master thesis is an experimental investigation of the acoustic characteristics of absorbing materials used in mufflers for trucks and cars. The difference in the composition between different wool type materials consists of difference in material, fibre diameter, length, density and fibre orientation. It is also possible to construct mufflers using micro perforated plates (MPP), either solely or in combination with wool type materials. When a specific material is selected the characteristics of the performance can be altered by compressing the material to different bulk densities. It was investigated how some of these properties change the airflow resistivity of the material. When the airflow resistivity of the material is known this parameter can be used in FEM software to describe how a specific material will react, behave and perform as an absorbent. Two different methods were used to extract the airflow resistivity. The fastest method is from the ISO standard ISO 9053 were the airflow resistivity is measured over a sample with a flow speed down to 0.5 mm/s. The second method is the Transfer Matrix Method (TMM) with which the airflow resistivity is extracted from the acoustic transfer matrix of the sample. Both methods are fully described in the report. The TMM was used within a frequency range of 0‐1600 Hz at no flow conditions. Measurements using both methods were performed at room temperature . Ten different wool type materials and two different kinds of MPP were studied. For the wool type materials, the airflow resistivity was measured with the fibres parallel and perpendicular to the direction of sound and airflow. The material samples had bulk densities of 80‐210 g/l. For the MPP the specific airflow resistance was measured with the static flow perpendicular to the plates. The results from the two methods were compared and the transmission loss, absorption coefficient, reflection coefficient and the complex speed of sound were calculated using the transfer matrix from the TMM. Regarding the TMM these data were also compared to the results that can be calculated when using the measured airflow resistivity together with the empirical expressions from Delany‐Bazley & Miki. Repacking of some materials were done in order to study the differences introduced by the packing process. IV The conclusions after the measurements were: • The agreement between the two methods was very good. • The value of the resistivity was doubled for measurements with the fibres perpendicular to the direction of sound. • When the materials with a high degree of micro strands were oriented with the fibres perpendicular to the direction of sound there was a resonant behaviour in the sample. The onset frequency of this resonance increased with increasing bulk density. This resonance leads to difficulties in predicting the behaviour of real life exhaust systems. • In order to get reliable results, further studies on the micro perforated plates must be made, with even lower flow velocities and sound pressure levels and maybe with other methods.
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Bruijn, Christina Geertruida de. "Voice quality after dictation to speech recognition software : a perceptual and acoustic study." Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440907.
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Masaki, Asako. "Optimizing acoustic and perceptual assessment of voice quality in children with vocal nodules." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54666.
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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 105-109).
Few empirically-derived guidelines exist for optimizing the assessment of vocal function in children with voice disorders. The goal of this investigation was to identify a minimal set of speech tasks and associated acoustic analysis methods that are most salient in characterizing the impact of vocal nodules on vocal function in children. Hence, a pediatric assessment protocol was developed based on the standardized Consensus Auditory Perceptual Evaluation of Voice (CAPE-V) used to evaluate adult voices. Adult and pediatric versions of the CAPE-V protocols were used to gather recordings of vowels and sentences from adult females and children (4-6 and 8-10 year olds) with normal voices and vocal nodules, and these recordings were subjected to perceptual and acoustic analyses. Results showed that perceptual ratings for breathiness best characterized the presence of nodules in children's voices, and ratings for the production of sentences best differentiated normal voices and voices with nodules for both children and adults. Selected voice quality-related acoustic algorithms designed to quantitatively evaluate acoustic measures of vowels and sentences, were modified to be pitch-independent for use in analyzing children's voices. Synthesized vowels for children and adults were used to validate the modified algorithms by systematically assessing the effects of manipulating the periodicity and spectral characteristics of the synthesizer's voicing source.
(cont.) In applying the validated algorithms to the recordings of subjects with normal voices and vocal nodules, the acoustic measure tended to differentiate normal voices and voices with nodules in children and adults, and some displayed significant correlations with the perceptual attributes of overall severity of dysphonia, roughness, and/or breathiness. None of the acoustic measures correlated significantly with the perceptual attribute of strain. Limitations in the strength of the correlations between acoustic measures and perceptual attributes were attributed to factors that can be addressed in future investigations, which can now utilize the algorithms that were developed in this investigation for children's voices. Preliminary recommendations are made for the clinical assessment of pediatric voice disorders.
by Asako Masaki.
Ph.D.
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Knight, Elizabeth Johnson. "The Effect of Head Flexion/extension on Acoustic Measures of Singing Voice Quality." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500127/.
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A study was undertaken to identify the effect of head flexion/extension on singing voice quality. The amplitude of the fundamental frequency (F0), and the singing power ratio (SPR), an indirect measure of singer’s formant activity, were measured. F0 and SPR scores at four experimental head positions were compared with the subjects’ scores at their habitual positions. Three vowels and three pitch levels were tested. F0 amplitudes and low frequency partials in general were greater with more extended head positions, while SPR increased with neck flexion. No effect of pitch or vowel was found. Gains in SPR appear to be the result of damping low frequency partials rather than amplifying those in the singer’s formant region. Raising the amplitude of F0 is an important resonance tool for female voices in the high range, and may be of benefit to other voice types in resonance, loudness, and laryngeal function.
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Selent, Mark. "Acoustic and Respiratory Measures as a Function of Age in the Male Voice." Cleveland State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=csu1401368326.
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Brandås, Linn Tove. "Relating acoustic wave velocities to formation mechanical properties." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for petroleumsteknologi og anvendt geofysikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18408.
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Proper correlation between formation mechanical properties and acoustic data is essential for acquiring field rock mechanical data for analysis, and it has thereby a great significance to oilfield development.This thesis presents results from a correlation study between formation mechanical properties and acoustic wave velocities from a set of unpublished rock mechanical experiments on sandstone samples from the Norwegian shelf. The core samples from the Norwegian shelf were subjected to triaxial compression tests performed at various confining pressures with simultaneous measurements of acoustic velocities. Correlations between formation compressive strength, elastic stiffness and Poisson's ratio and compressional and shear transit time have been established.The results obtained in this study confirm that the stress level and the stress configuration affect the acoustic velocities, and this should be accounted for when using generalized empirical correlations to estimate formation strength, elastic stiffness and Poisson's ratio from acoustic logs in field studies. The empirical correlations established through this work are found to match reasonable well with other published relations. By acoustic logs from field studies, it is found that the empirical correlations overestimate the formation strength and the elastic stiffness.
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Swift, Mark Jonathan. "Acoustic and Physical Properties of Poro-Elastic Media." Thesis, University of Bradford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520232.
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Taylor, Mark Victor. "Acoustic and instability properties of coaxial jet flows." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238545.
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Churches, David K. "The electromagnetic and acoustic properties of smoke particulates." Thesis, Open University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323122.
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Mahasaranon, Sararat. "Acoustic and thermal properties of recycled porous media." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5516.
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This thesis is concerned with developing porous materials from tyre shred residue and polyurethane binder for acoustic absorption and thermal insulation applications. The resultant materials contains a high proportion of open, interconnected cells that are able to absorb incident sound waves through viscous friction, inertia effects and thermal energy exchanges. The materials developed are also able to insulate against heat by suppressing the convection of heat and reduced conductivity of the fluid locked in the large proportion of close-cell pores. The acoustic absorption performance of a porous media is controlled by the number of open cells and pore size distribution. Therefore, this work also investigates the use of catalysts and surfactants to modify the pore structure and studies the influence of the various components in the chemical formulations used to produce these porous materials. An optimum type and amounts of catalyst are selected to obtain a high chemical conversion and a short expanding time for the bubble growth phase. The surfactant is used to reduce the surface tension and achieve a homogenous mixing between the solid particulates tyre shred residue, the water, the catalyst and the binder. It is found that all of the components significantly affect the resultant materials structure and its morphology. The results show that the catalyst has a particularly strong effect on the pore structure and the ensuing thermal and acoustical properties. In this research, the properties of the porous materials developed are characterized using standard experimental techniques and the acoustic and thermal insulation performance underpinned using theoretical models. The important observation from this research is that a new class of recycled materials with pore stratification has been developed. It is shown that the pore stratification can have a positive effect on the acoustic absorption in a broadband frequency range. The control of reaction time in the foaming process is a key function that leads to a gradual change in the pore size distribution, porosity, flow resistivity and tortuosity which vary as a function of sample depth. It is shown that the Pade approximation is a suitable model to study the acoustic behaviour of these materials. A good agreement between the measured data and the model was attained.
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Cicirello, Alice. "Vibro-acoustic analysis of structures with uncertain properties." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608078.
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Sun, Ruting (Michelle). "Characterization of the acoustic properties of cementitious materials." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/27308.
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The primary aim of this research was to investigate the fundamental acoustic properties of several cementitious materials, the influence of mix design parameters/constituents, and finally the effect of the physical and mechanical properties of cementitious material concrete/mortar on the acoustic properties of the material. The main objectives were: To understand the mechanism of sound production in musical instruments and the effects of the material(s) employed on the sound generated; To build upon previous research regarding selection of the tested physical/mechanical properties and acoustic properties of cementitious materials; To draw conclusions regarding the effect of different constituents, mix designs and material properties upon the acoustic properties of the material; To build a model of the relationship between the acoustic properties of a cementitious material and its mix design via its physical/mechanical properties. In order to meet the aim, this research was conducted by employing the semi-experimental (half analytical) method: two experimental programmes were performed (I and II); a mathematical optimization technique (least square method) was then implemented in order to construct an optimized mathematical model to match with the experimental data. In Experimental Programme I, six constituents/factors were investigated regarding the effect on the physical/mechanical and acoustic properties: cementitious material additives (fly ash, silica fume, and GGBS), superplasticizer, and basic mix design parameters (w/c ratio, and sand grading). 11 properties (eight physical/mechanical properties: compressive strength, density, hardness, flexural strength, flexural modulus, elastic modulus, dynamic modulus and slump test; and three acoustic properties: resonant frequency, speed of sound and quality factor (internal damping)) were tested for each constituents/factors related mortar type. For each type of mortar, there were three cubes, three prisms and three cylinders produced. In Experimental Programme I, 20 mix designs were investigated, 180 specimens produced, and 660 test results recorded. After analysing the results of Experimental Programme I, fly ash (FA), w/b ratio and b/s ratio were selected as the cementitious material/factors which had the greatest influence on the acoustic properties of the material; these were subsequently investigated in detail in Experimental Programme II. In Experimental Programme II, various combinations of FA replacement level, w/b ratios and b/s ratios (three factors) resulted in 1122 test results. The relationship between these three factors on the selected 11 properties was then determined. Through using regression analysis and optimization technique (least square method), the relationship between the physical/mechanical properties and acoustic properties was then determined. Through both experimental programmes, 54 mix designs were investigated in total, with 486 specimens produced and tested, and 1782 test results recorded. Finally, based upon well-known existing relationships (including, model of compressive strength and elastic modulus, and the model of elastic modulus and dynamic modulus), and new regressioned models of FA-mortar (the relationship of compressive strength and constituents, which is unique for different mixes), the optimized object function of acoustic properties (speed of sound and damping ratio) and mix design (proportions of constituents) were constructed via the physical/mechanical properties.
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Mvubu, Mlando Basel. "Studies on acoustic properties of non-woven fabrics." Thesis, Nelson Mandela Metropolitan University, 2017. http://hdl.handle.net/10948/19387.
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This study is divided in to two main parts. The first part deals with the optimization of process parameters of needle-punched non-woven fabrics for achieving maximum sound absorption by employing a Box-Behnken factorial design. The influence of fibre type, depth of needle penetration and stroke frequency on sound absorption properties were studied. These parameters were varied at three levels during experimental trials. From multiple regression analysis, it was observed that the depth of needle penetration alone was the most dominant factor among the selected parameters, which was followed by the interaction between depth of needle penetration and stroke frequency. Fibre type was the least dominant parameter affecting sound absorption. A maximum sound absorption coefficient of 47% (0.47) was obtained from the selected parameters. The results showed that for a process such as needle-punching, which is influenced by multiple variables, it is important to also study the interactive effects of process parameters for achieving optimum sound absorption. The second part of the study deals with the effect of type of natural fibre (fineness), and the blending ratio (with PET fibres) on the air permeability of the needle-punched non-woven fabrics and then it proceeds to study the effect of the air-gap, type of natural fibre (fineness) and blending ratio (with PET fibres) on sound absorption of needle-punched non-woven fabrics. These parameters are tested individually and their two way interaction (synergy) effect using ANOVA. The air-gap was varied from 0mm to 25mm with 5mm increments, three natural fibre types were used and all were blended with polyester fibres at three blending ratios for each natural fibre type. The Univariate Tests of Significance shows that all three parameters have a significant effect on sound absorption together with two two-way interactions, with the exception of the Blend Ratio × Air Gap two-way interaction which was not significant. It was found that the sound absorption improves with the increase in the air-gap size up to 15mm after which sound absorption decreased slightly with the further increase in the air-gap up to 25mm.
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Johnson, Wayne Michael. "Structural acoustic optimization of a composite cylindrical shell." Diss., Available online, Georgia Institute of Technology, 2004:, 2004. http://etd.gatech.edu/theses/available/etd-06072004-131213/unrestricted/johnson%5Fwayne%5Fm%5F200405%5Fphd.pdf.
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Ellis, A. Stephanie. "Effects of acoustic resynthesis on the perception of spasmodic dysphonia and essential voice tremor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq30787.pdf.
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Sahrawat, Ramesh. "The influence of inhaled corticosteroids on normal voice production in adults : an acoustic study." Thesis, University of Canterbury. Health Sciences Centre, 2010. http://hdl.handle.net/10092/4964.
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Corticosteroids are the most potent and reliable of the available agents among the anti-inflammatory drugs, and have assumed a major role in the management of asthma. This has subsequently resulted in the global widespread use of inhaled corticosteroids (ICS). A variety of studies have been undertaken to examine the effects of ICS on voice production among people with asthma. Most research suggests that the long-term use of ICS has a negative effect on voice production. However, the results of these studies are limited because of the reliance upon examining an asthmatic population and not consistently recording the dose prescribed. As a result, one cannot exclude that some of the voice problems may have been previously caused by asthma and thus, the contributing effects of ICS are obscured. Therefore, an ideal approach to examine the influence of ICS on voice is to test its short-term effects on healthy individuals, using a specific ICS (Fluticasone Propionate) at a fixed dose (1000 µg/Day). Thirty healthy adults (15 females & 15 males) aged between 18 to 30 years participated in this study. All participants were non-smokers with no history of speech, language or voice disorder. No participants had a history of asthma, respiratory illness hospital admission or inhaler use within the past 3 months. All participants followed the treatment regime often prescribed by physicians (in Canterbury region) for treating asthma (500 µg in morning & 500 µg in evening). Each participant self administered (inhaled) two puffs of ICS in the morning and again in the evening over a six day period. Voice samples were audio-recorded prior to undergoing the ICS regime, at various points during the ICS regime, and at the conclusion of ICS regime. Each participant’s audio-recorded samples were submitted for acoustic analysis using a commercially available speech analysis system (CSL 4300B, Kay Elemetrics, 1994). Three measures were performed, (1) vocal fundamental frequency (F0), (2) long-time spectral analysis (LTAS) and (3) formant frequency and formant frequency bandwidth. The results of this study indicate that ICS does have an effect on acoustic properties of voice. These effects were more evident in connected speech compared to isolated vowel productions. In particular, the spectral tilt and first spectral peak of continuous speech samples were found to change from baseline. The current results are discussed in regard to the phonatory deterioration associated with ICS use. The present study provides a framework for developing ICS treatment for respiratory disease in the phase of minimizing adverse effects on voice.
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Gray, Calum David. "Acoustic pulse reflectometry for measurement of the vocal tract and application in voice synthesis." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/13947.
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In this thesis, the basic theory describing wave propagation in tubes of varying cross-section is outlined, together with a review of how the time domain technique of APR can be used to measure the input impulse response of a tubular object, such as the vocal tract, from which the bore profile can be calculated using the layer peeling algorithm. Experimental measurements of the human vocal tract during the phonation (imitation of) for five non-nasalised vowels [a, e, i, o, u] are presented, using recent enhancements to the APR technique (MLS excitation signals and virtual DC tube method) for a single subject, together with optimisation of the APR technique for vocal tract measurement and its application in a group study using adults and children. To validate the results obtained using the APR technique, a comparative study with an accepted ‘gold standard’ imaging technique (MRI) is presented, using the same subject, a voice professional, in both studies. The results from this study show reasonable overall agreement between the APR and MRI data, with the limited resolution of the acoustic technique tending to broaden features and underestimate cross sectional areas, particularly in the region of the pharynx and glottis. Protocols and supplementary documentation required by scientific, clinical and ethical review bodies for the use of human volunteers in research trials are documented. From this study a data corpus of vocal tract measurements is gathered, using the techniques of APR and MRI, in adult males, adult females and children. In concluding, limitations of the APR technique for vocal tract measurement are discussed and potential improvements are proposed.
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Ng, Yuk-sim Cherry. "Perceptual and acoustic analysis of dysarthric dysphonia direct magnitude estimation versus interval scaling /." Click to view the E-thesis via HKUTO, 2002. http://sunzi.lib.hku.hk/hkuto/record/B36208425.
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Thesis (B.Sc)--University of Hong Kong, 2002."A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science (Speech and Hearing Sciences), The University of Hong Kong, May 10, 2002." Also available in print.
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Li, Yee-key Nicole, and 李依祺. "Acoustic and perceptual analysis of modal and falsetto registers in females with dysphonia." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B26653278.
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Guimarães, Michelle Ferreira. "Analise acustica da voz de adolescentes do sexo masculino durante a puberdade." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309760.
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Orientador: Ivone PanhocaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: A voz e a habilidade vocal são diferentes em cada indivíduo. Devido aos escassos estudos sobre a qualidade vocal de adolescentes durante a puberdade, o presente estudo tem como objetivo identificar os seguintes parâmetros da análise acústica da voz: freqüência fundamental, seus índices de perturbação a curto prazo {jitter e shimmer), proporção GNE (glottal noise excitation), ruído, semitons e intensidade; correlacioná-los entre e si e também com o grau do desenvolvimento puberal de adolescentes do sexo masculino. Métodos: Foram sujeitos desse estudo 46 adolescentes do sexo masculino, com idade entre ] 3 e 15 anos, estudantes de uma escola estadual de Campinas, onde foi feita a coleta dos dados. Os adolescentes foram submetidos à gravação da voz, em gravador digital. Solicitou-se emissão sustentada da vogal /s/ e fala encadeada: contagem de 1 a 10, emissão dos meses do ano e leitura de um trecho pré-estabelecido. Em seguida foram avaliados por uma médica pediátrica para caracterização do grau do desenvolvimento puberal de acordo com os estágios descritos por Tanner (G1 a G5). A análise vocal foi realizada com o programa acústico Voz Metria®. Resultados: A maioria dos adolescentes está entre G3 e GA, a freqüência fundamental média é de 261,5Hz e todos apresentaram freqüência fundamental acima de 200Hz. Jitter manteve-se com média de 0,26% (dentro dos padrões de normalidade). Shimmer mostrou-se alterado em 38 dos 46 indivíduos, apresentando média de 8,41%, considerado acima do limite de normalidade. A proporção GNE e ruído estão dentro dos limites de normalidade para todos os adolescentes, porém todos apresentaram quantidade de semitons acima do esperado. A freqüência fundamental é mais aguda em G4 e G5 (p=0,003), shimmer é alterado em freqüências mais agudas (p=0,008). Conclusão: Os adolescentes estudados possuem freqüência fundamental de característica infantil e feminina, apesar de estarem no início do desenvolvimento puberal adulto, além disso, a maioria deles apresentou shimmer alterado. A maturação da voz provavelmente ocorre após a maturação do desenvolvimento puberal
Abstract: Voice and voice ability are different in each person. Due to scarce studies about adolescents' voice, this study purpose to correlate voice fundamental frequency and its quotients of perturbation at short terra (jitter and shimmer), GNE (glottal noise excitation) values, half-tone, present noise, intensity and the degree of puberty development in male teenagers. Methods: It is a transversal study with 46 boys, with age varying from 13 to 15 years, students from a public school in Campinas (Brazil), where the study was performed. The adolescent's voices were recorded in digital recorder and the speech samples consisted of the vowel /e/ in sustained phonation, counting (from 1 to 10), saying the months of the year and reading. Afterwards, the pediatrician evaluated and characterized the puberty development according to the Tanner stages. The vocal analysis was made in Vox Metria® acoustic programmer. Results: Most of the boys were in G3 and G4 Tanner stages, the mean of fundamental frequency was 261.5Hz and all the adolescents had FO > 200Hz. The mean of jitter was 0.26%, showing it was at normality standard. Shimmer was increased in 38 of 46 boys, which mean was 8.41%. The values of GNE and noise were in the normality limit; nevertheless the half-tones were above the standard. The fundamental frequency was high-pitched in boys with G4 e G5 (p=0,003) and shimmer was increased in high-pitched (p=0,008). Conclusion: These boys have fundamental frequency with childish and feminine characteristics although they are in the beginning of adult genitals development, most of they have alteration in shimmer values. Voice maturation probably occurs after pubertal maturation
Mestrado
Saude da Criança e do Adolescente
Mestre em Saude da Criança e do Adolescente