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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.
111

"You must stay for dinner; we're having cud" : A study of the relationship between Swedish speakers' perception and production of English vowels

Sjösteen, Sigrid January 2010 (has links)
Learning a second language is different from learning our first one. A lot of rules from the first language, concerning e.g. grammar, intonation and phonology, are so firmly rooted within learners that they will transfer them to the new language regardless of whether they are correct or not. Studies show that the way we are tuned in to the sounds of our first language can make it difficult for us to perceive the phonemes of a new language correctly. In order to study the relationship between Swedish speakers’ faulty production of English vowels and their perception of them, ten subjects participated in a perception test to find out how well they could distinguish between minimal pairs containing phonemes that Swedes often have problems pronouncing correctly. They were also recorded while reading sentences containing the same minimal pairs. The results from the perception test were compared to graphs showing how consistent the subjects were in their pronunciation of these phonemes. The study shows that although some phonemes proved to be more difficult for the subjects to perceive a difference between, a faulty production of these sounds cannot be explained by misperception alone.
112

Stressed Syllables in Argentine Spanish in Queens, NYC: Lengthening and F0 Early Peak Alignment

Meiling, Giselle Gimenez 01 May 2015 (has links) (PDF)
This thesis investigates the intonation of Argentine Spanish in Queens, NYC, with the goal of verifying if the unique prosody of producing early peak alignments in the F0 of Argentine Spanish, specifically of Porteños (those from Buenos Aires), is maintained among the intense contact influences with other varieties of Spanish in the area. Previous studies have reported this early peak alignment phenomenon in the Spanish spoken in Buenos Aires, and this paper strives to see if this still occurs among Argentine Spanish speakers in New York City. The Buenos Aires speakers were compared with other native Argentine Spanish speakers in New York City who originated from provinces other than Buenos Aires (primarily from Mendoza) to verify if the dialectal varieties of Argentine Spanish had remained the same under the intense language contact situation of living in Queens. The data in the current study are from interviews recorded during the summer of 2014 in the Queens, NYC neighborhood of Elmhurst. Acoustic information obtained includes total syllable duration, F0 measurements, and F0 patterns. Additional linguistic variables included vowel type and vowel syllable position within a word. Extralinguistic variables included speaker sex, age, origin in Argentina, educational level, number of years in NYC, and number of years in Argentina. Results indicate that early peak alignment does indeed occur among Argentine speakers in Queens, NYC; however, it is interesting to note that it not only occurs in the informants from Buenos Aires as predicted, but in the informants from outside Buenos Aires as well. This suggests that the Outside Buenos Aires speakers are undergoing prosodic dialectal leveling with their pitch accent patterns and an increase in stressed syllable duration as occur naturally among the Buenos Aires speakers.
113

Percepção e produção das vogais anteriores arredondadas [y], [ë] e [ê] do francês por locutoras nativas do português brasileiro (L1), proficientes em francês (L2) / Perception and production of front rounded vowels [y], [q], and [E] of French by native speakers of Brazilian Portuguese (L1), proficient in French (L2)

Silva-Pinto, Giulian da 16 September 2016 (has links)
Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2017-05-05T23:23:43Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - SILVA-PINTO (2016).pdf: 21201769 bytes, checksum: 9aa83582fd61c6b36c3b56e9436a66ca (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-05-05T23:24:42Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - SILVA-PINTO (2016).pdf: 21201769 bytes, checksum: 9aa83582fd61c6b36c3b56e9436a66ca (MD5) / Made available in DSpace on 2017-05-05T23:24:52Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - SILVA-PINTO (2016).pdf: 21201769 bytes, checksum: 9aa83582fd61c6b36c3b56e9436a66ca (MD5) Previous issue date: 2016-09-16 / Sem bolsa / Este estudo investiga a aquisição das vogais anteriores arredondadas [y], [q] e [E] do francês por locutoras brasileiras adultas, proficientes em francês (L2). De acordo com a literatura (ALCÂNTARA, 1998; RESTREPO, 2011), a aquisição das vogais anteriores arredondadas do francês por aprendizes adultos brasileiros mostra-se uma tarefa complexa, tanto em termos de percepção quanto de produção. Diante disso, neste trabalho, procuramos contribuir ao entendimento dessa complexidade e fomentar os poucos estudos brasileiros envolvendo sujeitos proficientes em francês (L2) e a aquisição dos referidos sons. Desse modo, buscamos responder de que maneira os locutores brasileiros adultos, proficientes em francês (L2), lidam com sons alheios à fonologia da sua LM, no que concerne à sua percepção e produção. Para tanto, objetivamos, especificamente, detectar o grau de acuidade com o qual as vogais-alvo são identificadas e discriminadas pelas participantes avaliadas, bem como definir o comportamento acústico desses sons em sua fala, de modo que seja possível explicar uma provável produção autêntica dos segmentos franceses investigados em função de as informantes os identificarem, discriminarem e articularem. Diante disso, dois grupos de informantes participam desta pesquisa: o composto pelas brasileiras, três professoras-pesquisadoras de FLE no ensino superior público brasileiro, residentes em Pelotas/RS, e o formado por uma locutora francesa nativa, da região parisiense, a qual constitui o grupo controle e cujos dados se somam aos disponíveis na literatura. Para a coleta dos dados de produção em ambos os grupos, foram elaborados quatro experimentos, três envolvendo vogais orais francesas e o outro vogais orais do PB, as quais se encontravam em palavras e logatomas do francês e do PB, produzidos dentro de frases-veículo. Para a coleta dos dados de percepção relativos às vogais do francês, foram construídos quatro experimentos, dois testes de identificação e dois testes de discriminação. A metodologia utilizada na construção desses experimentos foi baseada, em parte, naquela elaborada por Restrepo (2011), com adaptações para atender aos objetivos específicos deste trabalho. As coletas ocorreram em ambiente acústico controlado (cabine acústica), com a utilização de um gravador digital Zoom H4N e de um par de fones de ouvido modelo AKG K 44. Os dados coletados foram analisados acústica e estatisticamente, por meio dos softwares Praat (versões 6.0.08 e 6.0.19) e SPSS Statistics (versão 17.0), respectivamente. Os resultados obtidos, interpretados à luz do modelo HipCort (MCCLELLAND et al.,1995), um modelo dinâmico de formação da memória e do aprendizado, confirmam nossa tese do potencial êxito de nossas informantes na aquisição dos sons investigados, pois identificam, discriminam e produzem acuradamente as vogais anteriores arredondadas do francês, demonstrando terem se distanciado de uma possível influência de sua LM. Os resultados alcançados contribuem, portanto, para se refutar a existência da atuação de restrições biológicas ligadas a uma concepção de aquisição da linguagem calcada nos pressupostos do paradigma simbólico, indo ao encontro de estudos que evidenciam a possibilidade de aprendizes tardios apresentarem um nível de competência fonético-fonológica em L2 comparável àquele do falante nativo. / This study investigates the acquisition of front rounded vowels [y], [q], and [E] of French by adult female speakers who are proficient in French (L2). According to the literature (ALCÂNTARA, 1998; RESTREPO, 2011), the acquisition of front rounded vowels of French by Brazilian adult learners is a complex challenge, either in terms of perception or in terms of production. From this point, in this study we sought to contribute to the understanding of this complexity and develop the not many Brazilian studies involving individuals with proficiency in French language (L2) and the acquisition of its sounds. Thus, our challenge was to answer in what way adult Brazilian speakers, with proficiency in French (L2), deal with foreign sounds, different from the ones of their ML phonology, when it comes to their perception and production. Therefore, we aimed to detect, specifically, the level of perceptiveness with which the target vowels are identified and distinguished by the considered participants, as well as defining the acoustic behaviour of these sounds in their speaking, in a possible way to explain a probable authentic production of the investigated French segments according to the identification, distinction, and articulation of the participants. Then, two groups of volunteers participated in this research: one counts with the presence of three Brazilian women, professors and researchers of FFL in superior public education, residents in Pelotas/RS; the second group is formed by a native French speaker from Parisian region, who participates of the control group, which data is added to the one available in literature. For the collecting of data of production in both groups, four experiments were elaborated, three involving French oral vowels, and the last one involving oral vowels of BP, which were found in words and non-words from French and BP, produced inside of carrier sentences. For the collecting of information of perception related to the French vowels, four experiments were formed, two tests of identification, and two tests of distinction. The methodology used in the construction of these experiments was based on the one elaborated by Restrepo (2011), with adaptions to attend to the specific objectives of this study. The collection of the material occurred in a controlled acoustic environment (acoustic compartment), with the use of a digital recorder Zoom H4N and a pair of earphones model AKG K 44. The collected data was analysed acoustically and statistically with the softwares Praat (6.0.08 and 6.0.10 versions) and SPSS Statistics (17.0 version), respectively. The results achieved were interpreted with the HipCort model (MCCLELLAND et al, 1995), a dynamic model of formation of memory and learning. They confirmed our thesis of the potential outcome of our participants in the acquisition of the investigated sounds, because they could identify, distinguish, and produce accurately the front rounded vowels of French, demonstrating the distance of a possible influence from their ML. The results contribute, so, to refute the existence of an operation of biological restrictions connected to a conception of acquisition of language based on the presupposition of the symbolic paradigm, which meets the studies that evince the possibility of late learners to present a level of phonetic and phonologic competences in L2 comparable to the native speaker.
114

Stress shift in English rhythm rule environments : effects of prosodic boundary strength and stress clash types

Azzabou-Kacem, Soundess January 2018 (has links)
It is well-known that the early assignment of prominence in sequences like THIRteen MEN vs. thirTEEN, (defined as the Rhythm Rule, or post-lexical stress shift), is an optional phenomenon. This dissertation examines some of the factors that encourage the application of stress shift in English and how it is phonetically realised. The aim is to answer two sets of questions related to why and how stress shift occurs in English: 1a) Does prosodic boundary strength influence stress shift? 1b) Does the adjacency of prominences above the level of the segmental string encourage stress shift? 2) How is stress shift realized? a) Is stress shift only a perceptual phenomenon? and b) Which syllables, if any, change acoustically when stress shift is perceived? To answer these questions, four experiments were designed. The first three experiments test whether the strength of the prosodic boundaries before and after the target word (e.g., canteen) influence stress shift. The effect of the strength of the left-edge prosodic boundary was investigated by comparing perceived stress patterns of the target (e.g., canteen) as produced in isolation where it is preceded by an utterance- and a phrase- initial prosodic boundary (the Isolated condition) with its rendition when embedded in a frame sentence (e.g., Say canteen again) where the left prosodic boundary before canteen is weaker (the Embedded condition). Results show a very clear tendency towards late phrasal prominence on the final accentable syllable (e.g., -teen in canteen) in the Embedded condition while in the Isolated condition this pattern appeared in less than half of the targets, showing that the stronger left boundary increased the incidence of stress shift. Two more experiments manipulated the strength of the boundary to the right of the target (#) respectively by changing the syntactic parse of the critical phrase (e.g. canteen cook) in sequences like (1) and by manipulating constituent length as in (2). Results showed that the syntactic manipulation significantly affected the strength of the prosodic boundary between the clashing words which was stronger in (1b) relative to (1a), and affected the incidence of stress shift, which was higher in (1a) relative to (1b). The length manipulation also affected the rate of stress shift, which was significantly higher in the phrase with the shorter word, e.g., soups (2a) relative to phrase with the longer word, e.g., supervisors (2b). (1) Example from the Syntax Experiment a. Who is the canteen (#) cook these days? (Pre-modifier + Noun) b. How do the canteen (#) cook these days? (NP + VP) (2) Example from the Length Experiment a. It should include the canteen (#) soups again. (Shorter constituent) b. It should include the canteen (#) supervisors again. (Longer constituent) Whilst we knew from the literature that the grouping of the clashing words within one Intonational Phrase (IP) encourages stress shift, results from the Syntax and Length experiments indicate that this (i.e., the phrasing of the clashing words within same IP) is not sufficient condition for the occurrence of stress shift, and that fine-grained degrees of boundary strength below the Intonational Phrase can drive changes in prominence pattern. The fact that higher rates of stress shift (and associated significant acoustic changes) were driven by manipulations of constituent length --for sequences with the same syntactic structure-- provides support for the idea that prosodic (rather than syntactic) boundaries directly influence stress shift. The fourth experiment tests the definition of stress clash in English in cases like fourteen candles where the two main lexical prominences are strictly adjacent along the time dimension, in fourteen canoes where the prominences are not adjacent in time, but adjacent at the higher levels of the metrical hierarchy, and in fourteen canteens where the main lexical prominences are not adjacent, and do not clash. This experiment highlighted and resolved an unacknowledged disagreement about what clash status sequences with one weak intervening syllable (e.g., fourTEEN caNOES). The fourTEEN caNOES type were shown to behave like metrically clashing sequences (e.g., fourteen CANdles) in attracting stress shift, and differently from the non-metrically-clashing sequences (e.g., fourteen CANTEENS) in discouraging it. These results provide empirical support for the Standard Metrical Theory (e.g. Selkirk, 1984; Nespor & Vogel, 1989) claim that 1) stress clash matters in triggering stress shift and that 2) stress clash in English is defined at the higher prosodic levels and not restricted to the level of the segmental string as indirectly assumed in a growing body of research (e.g., Vogel, Bunnel & Hoskins, 1995; Tomlinson, Liu & Fox Tree, 2014). Along with the establishment of prosodic boundary strength as one of the predictors influencing stress shift, another important contribution of the thesis is providing empirical evidence that the English Rhythm Rule is not solely a perceptual phenomenon and that it is associated with acoustic correlates. The main correlates of perceived stress shift consistently appearing across experiments is the decrease in the duration of the main lexical prominence of the target (e.g., -teen in canteen) and the increase of fundamental frequency and Sound Pressure Level peaks and on the initial syllable (e.g., canin canteen), when followed by a main clashing phrasal prominence. The acoustic analysis shows that the first accentable syllable also contributes in the perception of stress shift. This latter result does not lend support to the deletion formulation of the Rhythm Rule (Gussenhoven, 1991) which stipulates that the impressions of stress shift are solely associated with changes of prominence in the last accentable syllable of the target (e.g. -teen in canteen). Along with the determination of the acoustic correlates of perceived stress shift in English, the present research 1) indicates that fine-grained gradations of prosodic boundary strength can influence stress shift, 2) shows that while stress clash can increase the incidence of stress shift, stress shift can take place even in environments completely free of stress clash, and 3) provides evidence that stress clash should not be construed simply as the concatenation of two main lexical prominences along the time dimension.
115

Temporal aspects of speech production in bilingual speakers with neurogenic speech disorders

Theron, Karin 07 August 2003 (has links)
The present study is the first to examine the effect of first versus second language (L1 versus L2) speech production on specific temporal parameters of speech in bilingual speakers with neurogenic speech disorders. Three persons with apraxia of speech (AOS), three with phonemic paraphasia (PP) and five normal speaking participants were included as subjects in the study. Subjects were required to read phonemically similar L1 and L2 target utterances in a carrier phrase, five times each, at a normal and fast speaking rate, respectively. This rendered four speaking contexts that included speech production in L1 at either a normal (L1NR) or fast speaking rate (L1FR) and speech production in L2 at either a normal (L2NR) or fast speaking rate (L2FR). Acoustic analysis of on-target productions involved measurement of utterance onset duration, vowel duration, utterance duration and voice onset time. Results revealed that in normal speakers, speech production in L2 results in greater token-to-token variability than in L1. However, token-to-token variability in the experimental subjects did not tend to increase whilst speaking in L2, most probably because these subjects generally decreased their speaking rate in this context, resulting in more consistent production. The subjects with AOS and PP seemed to be influenced by the increased processing demands of speaking in L2 to a greater extent than the normal speakers, in that they more frequently experienced difficulty with durational adjustments (decreasing duration in the fast speaking rate) in L2 than in L1. Furthermore, the subjects with AOS or PP also exhibited a greater extent of durational adjustment in L1 than in L2. The durations of most of the subjects with either AOS or PP tended to differ from those of the normal group to a greater extent in L2FR that was hypothesized to be the most demanding speaking context for these subjects. The longer than normal durations and greater than normal token-to-token variability in the subjects with either AOS or PP imply the presence of a motor control deficit. The extent of the motor control deficit appears to be more severe in AOS than in PP as is evident from the finding that the subjects with AOS generally exhibited longer durations and greater token-to-token variability than the subjects with PP. The pattern of breakdown in respect of different parameters and utterance groups also differed between subjects with AOS and PP. The nature of the disorder in AOS and PP thus appears to be both quantitatively and qualitatively different. Regarding measurement of the different temporal parameters, voice onset time appears to be less subject to the influence of L2 than the other measured temporal parameters. The results of this study imply that bilingual AOS is as much a reality as bilingual aphasia. Furthermore, the results underscore the importance of taking contextual factors, specifically L1 versus L2, into account when compiling assessment and treatment procedures for persons with either AOS or PP, since speech production in L2 appears to be motorically more difficult than in L1 for persons with neurogenic involvement. The significance of the results is discussed with reference to the influence of speech production in L2 on temporal control and the underlying nature of AOS and PP with regard to theories of speech sensorimotor control. Copyright / Dissertation (DPhil (Communication Pathology))--University of Pretoria, 2004. / Speech-Language Pathology and Audiology / unrestricted
116

Hodnocení Parkinsonovy nemoci na základě akustické analýzy hypokinetické dysartrie / Assessment of Parkinson’s Disease Based on Acoustic Analysis of Hypokinetic Dysarthria

Galáž, Zoltán January 2018 (has links)
Hypokinetická dysartrie (HD) je častým symptomem vyskytujícím se až u 90% pacientů trpících idiopatickou Parkinsonovou nemocí (PN), která výrazně přispívá k nepřirozenosti a nesrozumitelnosti řeči těchto pacientů. Hlavním cílem této disertační práce je prozkoumat možnosti použití kvantitativní paraklinické analýzy HD, s použitím parametrizace řeči, statistického zpracování a strojového učení, za účelem diagnózy a objektivního hodnocení PN. Tato práce dokazuje, že počítačová akustická analýza je schopná dostatečně popsat HD, speciálně tzv. dysprozodii, která se projevuje nedokonalou intonací a nepřirozeným tempem řeči. Navíc také dokazuje, že použití klinicky interpretovatelných akustických parametrů kvantifikujících různé aspekty HD, jako jsou fonace, artikulace a prozodie, může být použito k objektivnímu posouzení závažnosti motorických a nemotorických symptomů vyskytujících se u pacientů s PN. Dále tato práce prezentuje výzkum společných patofyziologických mechanizmů stojících za HD a zárazy v chůzi při PN. Nakonec tato práce dokazuje, že akustická analýza HD může být použita pro odhad progrese zárazů v chůzi v horizontu dvou let.
117

Objektivizace Testu 3F - dysartrický profil pomocí akustické analýzy / Objectification of the Test 3F - dysarthric profile based on acoustic analysis

Bezůšek, Marek January 2021 (has links)
Test 3F is used to diagnose the extent of motor speech disorder – dysarthria for czech speakers. The evaluation of dysarthric speech is distorted by subjective assessment. The motivation behind this thesis is that there are not many automatic and objective analysis tools that can be used to evaluate phonation, articulation, prosody and respiration of speech disorder. The aim of this diploma thesis is to identify, implement and test acoustic features of speech that could be used to objectify and automate the evaluation. These features should be easily interpretable by the clinician. It is assumed that the evaluation could be more precise because of the detailed analysis that acoustic features provide. The performance of these features was tested on database of 151 czech speakers that consists of 51 healthy speakers and 100 patients. Statistical analysis and methods of machine learning were used to identify the correlation between features and subjective assesment. 27 of total 30 speech tasks of Test 3F were identified as suitable for automatic evaluation. Within the scope of this thesis only 10 tasks of Test 3F were tested because only a limited part of the database could be preprocessed. The result of statistical analysis is 14 features that were most useful for the test evaluation. The most significant features are: MET (respiration), relF0SD (intonation), relSEOVR (voice intensity – prosody). The lowest prediction error of the machine learning regression models was 7.14 %. The conclusion is that the evaluation of most of the tasks of Test 3F can be automated. The results of analysis of 10 tasks shows that the most significant factor in dysarthria evaluation is limited expiration, monotone voice and low variabilty of speech intensity.
118

Contribution à l’étude des émissions vibro-acoustiques des machines électriques : cas des machines synchrones à aimants dans un contexte automobile / Study of noise and vibrations of electromagnetic origin in electrical machines : specific case of permanent magnet synchronous machines used in the automotive industry

Verez, Guillaume 02 December 2014 (has links)
Dans un contexte automobile électrique et hybride, la part des machines synchrones à aimants permanents s'est accrue exponentiellement. Cette évolution s'accompagne d'exigences en termes d'émissions vibro-acoustiques. En termes de dimensionnement de la chaîne de traction, l'analyse multiphysique du moteur s'avère être un enjeu crucial pour son développement. La nécessité de disposer de codes informatiques de conception possédant des temps de calcul faibles pour une précision maximale se fait ressentir pour l'exploration de solutions potentiellement performantes dans les premières étapes du processus de dimensionnement. A ce titre, les aspects vibratoires et acoustiques sont modélisés analytiquement et par éléments finis dans la présente thèse. Ainsi, au moyen du modèle magnétique, l'analyse magnéto-vibro-acoustique faiblement couplée (résolution itérative des différentes physiques) peut être réalisée.La thèse est découpée en quatre parties. La première expose un état de l’art sur les émissions vibro-acoustiques des machines et notamment la modélisation du bruit d’origine magnétique. Les problématiques de la modélisation sont détaillées. Dans une deuxième partie, les modèles sont largement décrits. Les modèles éléments finis sont validés expérimentalement. Une troisième partie se propose de valider les modèles analytiques par éléments finis, en complexifiant progressivement la géométrie d’une machine à aimants montés en surface à flux radial. Enfin, la dernière partie utilise les modèles éléments finis pour étudier des machines non-conventionnelles comme les machines à commutation de flux et les machines à aimants en surface à flux axial. / The proportion of permanent magnets synchronous motors used for electric and hybrid automotive traction has exponentially increased during the past decade. This evolution comes with ever-demanding low noise and vibrations requirements. Multi-physics analysis of the motor is a decisive issue for the development of the powertrain. For the exploration of potentially efficient motor solutions in first design steps, it is thus a necessity to have at disposal fast and accurate computer codes. In this respect, acoustic and vibratory aspects are modeled using finite element and analytical models in this thesis. As a result, using an electromagnetic model, the weakly-coupled magneto-vibro-acoustic analysis (iterative solving of each physic) can be performed.The thesis is divided into four parts. The first part states the art on machine vibro-acoustic emissions and focuses on noise of magnetic origins modeling. Issues of modeling are detailed. Then, models are described to a great extent in the second part. Finite element models are favorably compared to experimental measures. A third part validates analytical models in comparison to finite element analysis, by gradually complicating the geometry of a surface permanent magnets radial flux machine. Finally, a fourth part uses finite element models to study non-conventional machines such as flux switching radial flux machines and surface permanent magnets axial flux machines.
119

Door closing sound quality related to door sealing stiffness

Derton, Riccardo January 2021 (has links)
The door closing action is a recurrent situation when using a vehicle, and its sound is therefore a common sensation, which would elicit pleasant feelings. Sensory pleasantness is an important aspect in terms of customer’s perspective, and it can be a contributing factor when deciding to buy or not a specific vehicle. The first contact between a prospective customer and the automobile usually happens in car salons or at the car retailer. The initial impression of the vehicle might be sight-based, and the door may commonly be the first physical contact. Depending on the car brand and type, doors differ in terms of mass, structure, dimension. Furthermore, there are differences regarding the latching system and the door sealing structure, in terms of material and construction. The closing sound produced when slamming the door is related to all these parameters. Auditory pleasantness can be described by characteristics of the sound that are described through psychoacoustics. Loudness, sharpness, roughness, and tonality are important auditory parameters to objectively describe this complex sensation. The aim of car doors would be to generate an enthusiastic, low-pitched, and saturated sound, which would elicit feelings of solidity, robustness, and security. On the other side, a metallic, high-pitched, fragmented sound could be a source of annoyance and produce feelings of insecurity and cheap vehicle.The present work aims to provide a broad picture on the mechanics and acoustics of door closing for automobiles. In specific, the closing sound was evaluated in relation to the door gaskets and their sealing performance over time. The sealing performance was analyzed in energy and force terms. The door closing motion was studied as a quasi-static problem, as well as a dynamic problem, where the former is related to the latching capability of the door, the latter is connected to the slamming action. The measurement results include the sealing performance trend from fresh to aged gaskets. From these measurements, the rubber non-linear behaviour could then be evaluated from a sound quality perspective. The acoustic analysis revealed inconsistencies of the psychoacoustic parameters in the description of the hearing sensations. Spectral analysis was also implemented to capture the door closing phenomenon, and the Wavelet transform emerged as the method with the highest resolution in the description of the sound wave progression.Several measurements were performed in order to assess all the established points, and methods were implemented for the sealing stiffness analysis and the acoustic analysis. The severe transiency of the door closing event was put in evidence. The stiffness analysis method showed also potential in helping to adjust the end of line tuning of the vehicle. Finally, benchmarking was included in the project, which enabled comparisons with competitor cars. / Dörrstängning är en återkommande händelse när ett fordon används, och ljudet bör därför ge ett positivt intryck och korrekt information till brukaren. Ett behagligt intryck är en viktig aspekt ur kundens perspektiv och kan vara ett var flera bidragande faktorer när beslut tas om att köpa eller inte köpa ett fordon. Den första kontakten mellan en potentiell kund och bilen sker vanligtvis i bilsalonger eller hos bilhandlare. Det första intrycket av fordonet kan vara visuellt, och dörren är ofta den första fysiska kontakten. Beroende på biltyp och fabrikat skiljer sig dörrarna åt när det kommer till massa, struktur och dimensioner. Dessutom kan det finnas skillnader i låssystem och dörrtätningskonstruktion såsom i både material och utformning. Stängningsljudet som uppstår när dörren slås igen är relaterat till alla dessa parametrar. Ett ljuds upplevda behaglighet i det beror på ljudets egenskaper, som beskrivs med hjälp av psykoakustik. Ljudstyrka, skärpa, råhet och tonalitet är viktiga auditiva parametrar för att objektivt beskriva detta komplexa intryck. Målet med bildörrar bör vara att generera ett dovt och mättat ljud, för att framkalla känslor av soliditet, robusthet och säkerhet. Å andra sidan kan, ett metalliskt, högfrekvent och skramligt ljud vara en källa till irritation och ge känslor av osäkerhet och låg kvalité.Syftet med detta arbete är att ge en övergripande beskrivning av dörrstängning och akustiken kring detta. I synnerhet utvärderades stängningsljudet i förhållande till dörrpackningarna och deras tätningsprestanda mätt över tiden. Tätningsprestanda analyserades i energi- och krafttermer. Dörrens stängningsrörelse studerades både som ett kvasistatiskt problem och som ett dynamiskt problem. Det förstnämnda är relaterat till dörrens låsningsförmåga, medan det sistnämnda är kopplat till smällar i dörren. Mätresultaten visade hur tätningsprestandan förändras över tiden. Gummits icke-linjära beteende har också utvärderats med ett ljudkvalitetsperspektiv. En spektralanalys genomfördes av ljudet från dörrstängningar och Wavelet-transformen visade sig vara den lösning som gav bäst kvalitet. Flera mätningar utfördes för att bedöma alla fastställda punkter och metoder infördes för analysen av tätningens styvhet och för den akustiska analysen. Den kraftiga transiensen i dörrstängningen kunde ses i resultaten. Styvhetsanalysen visade även hur den utvecklade metoden skulle kunna bidra till att justera fordonets end-of-line inställningar. Slutligen ingick benchmarking i projektet vilket möjliggjorde jämförelser med konkurrentbilar.

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