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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.
81

Seleção e verificação no processo de adaptação de aparelhos de amplificação sonora individual e o impacto na percepção de fala em crianças

Rissatto, Mara Renata 09 October 2007 (has links)
Made available in DSpace on 2016-04-27T18:12:24Z (GMT). No. of bitstreams: 1 mara.pdf: 902402 bytes, checksum: 5593c4e51c3528bc143f385e516e4be4 (MD5) Previous issue date: 2007-10-09 / Objective: To characterize and to argue the application of a protocol of hearing aid adaptation verification in the in children as well as the impact of the acoustic characteristics in speech perception tasks adequacy. Method: Ten children aging from 3yr to 11yr 3mo were enrolled in this study. All children with bilateral cochlear hearing loss (average four-frequency hearing loss: from moderate to profound) and wearing hearing aid; derived from public hearing health care service in Bahia. The children had been submitted to the following procedures: pure tone air and bone conduction thresholds; real-ear coupler difference (RECD); verification with real-ear measurement equipment: coupler gain/output and insertion gain to actually compare the measurement in the child s ear with the correct prescribed for the child by software DSL [i/o] v4.1 and procedures of perception and production of speech: The Six-Sound Test Ling (2006) and Word Associations will be Syllabe Perception (WASP) by Koch (1999). Results: the performance of the hearing aid electro acoustic characteristics measured by 2cc coupler, which was the children real situation when they arrived, was compatible with under amplification and after proceeding the alteration according with the prescribed data provided by the DSL [i/o] software it was possible to verify, trough objective and speech perception procedures, the prescription adequacy. Conclusion: the use of a protocol within pediatric hearing aid adaptation, which includes: procedures of verification trough objective and speech performance measures is very important to the hearing health care services results / Objetivo: o objetivo deste estudo foi caracterizar e discutir a aplicação de um protocolo de verificação na adaptação do aparelho de amplificação sonora individual (AASI) em crianças, bem como o impacto da adequação das características acústicas em tarefas de percepção de fala. Método: a casuística foi composta de dez crianças, quatro do gênero masculino e seis do gênero feminino, com idades entre 3 e 11 anos, portadoras de perda auditiva de graus que variavam de moderado a profundo, usuárias de AASI bilateralmente e que estavam sendo atendidas na unidade de atenção à saúde auditiva de média complexidade da Bahia. As crianças foram submetidas aos seguintes procedimentos: audiometria; medida da diferença de pressão sonora no acoplador de 2cc e no meato acústico externo da orelha (RECD); verificação das características eletroacústicas (ganho e saída) programadas nos seus respectivos AASI por meio de medidas objetivas (medida derivada da resposta real realizada com o acoplador de 2cc e ganho de inserção) e medidas comportamentais (medida dos níveis mínimos de resposta do AASI em campo livre), para comparação com as características eletroacústicas prescritas pelo software DSL [i/o] v4.1. Também foram realizados procedimentos de percepção e produção da fala: detecção dos sons do Ling (2006) e protocolo de avaliação Word Associations for Syllabe Perception (WASP), proposto por Koch (1999). Resultados: o resultado do desempenho das características eletroacústicas no acoplador de 2cc mostrou que a programação dos AASI com a qual as crianças chegaram para o serviço estavam fornecendo uma subamplificação, sendo que, após a alteração e prescrição de acordo com o software do DSL [i/o], foi possível verificar, com os procedimentos objetivos, a adequação da prescrição, o que também foi confirmado nos procedimentos de percepção de fala. Conclusão: é necessária a utilização de um protocolo na adaptação do AASI na população infantil que inclua: procedimentos de verificação com medidas objetivas e validação. Sendo fundamental para que os objetivos da Política Nacional de Saúde Auditiva sejam atingidos
82

Saúde auditiva: estudo do grau de satisfação de usuários de aparelho de amplificação sonora

Farias, Rodrigo Brayner de 09 October 2007 (has links)
Made available in DSpace on 2016-04-27T18:12:26Z (GMT). No. of bitstreams: 1 Rodrigo Brayner de Farias.pdf: 318061 bytes, checksum: e4da610ef9ef7b6e2684d20aec13106b (MD5) Previous issue date: 2007-10-09 / Objectives: This study aimed at characterizing the hearing aid satisfaction of adult and aged individuals derived from public hearing health care services, investigating its relationship with some variables, such as sex, age, degree of hearing loss, hearing aid type and hearing aid electro acoustic profile and comparing its result with the normative data reported by the questionnaire s authors. Method: 39 individuals were evaluated, 21 males and 18 females, aged from 19 to 90 years. All of them had conductive, sensorineural or mixed, symmetric or asymmetric, mild, moderate or severe hearing loss and used their hearing aids from not less than four weeks and not more than 12 weeks. It was used the Satisfaction with Amplification in Daily Life - SADL questionnaire Results: There was statistically significant association in the relationship between hearing aid satisfaction and hearing aid type, where in the ear hearing aid users were more satisfied than behind the ear hearing aid users. SADL global and subscale scores were higher than those described by the questionnaire s authors. Conclusions: The conclusions point out to the importance of hearing aid satisfaction evaluation to validate the effectiveness of its adaptation, contributing to get better results / Objetivos: Este estudo teve como objetivo caracterizar o grau de satisfação de indivíduos adultos e idosos usuários de aparelhos de amplificação sonora (AAS) atendidos em serviços de saúde auditiva vinculados à Política Nacional de Atenção à Saúde Auditiva, investigando sua relação com as variáveis: sexo, idade, grau da perda auditiva, tipo de AAS e perfil eletroacústico do AAS e comparando os resultados apurados com os dados normativos estabelecidos pelas autoras do questionário. Método: Foram avaliados 39 indivíduos, sendo 21 do sexo masculino e 18 do sexo feminino, na faixa etária entre 18 e 90 anos. Todos eram portadores de perda auditiva pós-lingual adquirida dos tipos condutiva, sensorioneural ou mista, unilateral ou bilateral, simétrica ou assimétrica, de grau leve a severo e faziam uso de seus AAS pelo período mínimo de quatro e máximo de 12 semanas. O questionário utilizado foi o Satisfaction with Amplification in Daily Life SADL. Resultados: Observou-se associação estatisticamente significante quanto ao grau de satisfação relacionado com o tipo de AAS utilizado, sendo maior relativo aos que usavam aparelhos intra-aurais. Os índices apurados foram superiores aos da normatização estabelecida pelas autoras do questionário. Conclusões: As conclusões apontam para a importância da avaliação do grau de satisfação dos usuários de AAS para a validação da efetividade da sua adaptação, contribuindo para a obtenção de melhores resultados
83

Desempenho em tarefas de percepção de fala de crianças com deficiência auditiva: familiaridade da lista de palavras

Raimundo, Jesiela Cristina 29 July 2008 (has links)
Made available in DSpace on 2016-04-27T18:12:35Z (GMT). No. of bitstreams: 1 Jesiela Cristina Raimundo.pdf: 1178870 bytes, checksum: 5843a99b0dc5f1eb87e892e0991c7f83 (MD5) Previous issue date: 2008-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
84

Hearing Aid Outcomes in Patients with and without Posttraumatic Stress Disorder

McDowell, Julia, Smith, Sherri L., Fagelson, Marc A., Schairer, Kim 10 August 2016 (has links)
No description available.
85

Determinants of Department of Veterans Affairs Hearing Aid Brand Dispensing by Individual Audiologists

Johnson, Earl E. 01 January 2011 (has links)
Department of Veterans Affairs (VA) audiologists were surveyed regarding their perceptions and evaluations of hearing aid (HA) brands on seven factors previously published in peer-reviewed research as important to the HA brand preference decision of audiologists. One of the seven factors formed a distinct dimension of brand differentiation based on Contract Pricing (dimension 1). Brand perceptions for the other six factors were highly correlated with one another; this dimension of correlated perceptions was labeled Propensity to Dispense Based on a Gestalt Percept (dimension 2). That is, a direct relation exists between the collective perception of HA brand and its likelihood of being dispensed. These two dimensions accounted for 93.1% of the variance in the perceived differences among the HA brands surveyed. Joint-space mapping was used to model the effect of altering perceptions on VA HA brand dispensing. Results indicate that few VA audiologists (7.7%) dispense HA brands in majority association with contract pricing. Instead, the vast majority (77%) form brand preferences in majority association with their individualized perceptions.
86

A Comparison of NAL and DSL Prescriptive Methods for Paediatric Hearing-Aid Fitting: Predicted Speech Intelligibility and Loudness

Ching, Teresa Y.C., Johnson, Earl E., Hou, Sanna, Dillon, Harvey, Zhang, Vicky, Burns, Lauren, van Buynder, Patricia, Wong, Angela, Flynn, Christopher 01 December 2013 (has links)
Objective: To examine the impact of prescription on predicted speech intelligibility and loudness for children. Design: A between-group comparison of speech intelligibility index (SII) and loudness, based on hearing aids fitted according to NAL-NL1, DSL v4.1, or DSL m[i/o] prescriptions. A within-group comparison of gains prescribed by DSL m[i/o] and NAL-NL2 for children in terms of SII and loudness. Study sample: Participants were 200 children, who were randomly assigned to first hearing-aid fitting with either NAL-NL1, DSL v4.1, or DSL m[i/o]. Audiometric data and hearing-aid data at 3 years of age were used. Results: On average, SII calculated on the basis of hearing-aid gains were higher for DSL than for NAL-NL1 at low input level, equivalent at medium input level, and higher for NAL-NL1 than DSL at high input level. Greater loudness was associated with DSL than with NAL-NL1, across a range of input levels. Comparing NAL-NL2 and DSL m[i/o] target gains revealed higher SII for the latter at low input level. SII was higher for NAL-NL2 than for DSL m[i/o] at medium- and high-input levels despite greater loudness for gains prescribed by DSL m[i/o] than by NAL-NL2. Conclusion: The choice of prescription has minimal effects on speech intelligibility predictions but marked effects on loudness predictions.
87

A Comparison of Gain for Adults from Generic Hearing Aid Prescriptive Methods: Impacts on Predicted Loudness, Frequency Bandwidth, and Speech Intelligibility

Johnson, Earl E., Dillon, Harvey 01 July 2011 (has links)
Background: Prescriptive methods have been at the core of modern hearing aid fittings for the past several decades. Every decade or so, there have been revisions to existing methods and/or the emergence of new methods that become widely used. In 2001 Byrne et al provided a comparison of insertion gain for generic prescriptive methods available at that time. Purpose: The purpose of this article was to compare National Acoustic Laboratories—Non-linear 1 (NAL-NL1), National Acoustic Laboratories—Non-linear 2 (NAL-NL2), Desired Sensation Level Multistage Input/Output (DSL m[i/o]), and Cambridge Method for Loudness Equalization 2—High-Frequency (CAMEQ2-HF) prescriptive methods for adults on the amplification characteristics of prescribed insertion gain and compression ratio. Following the differences observed in prescribed insertion gain among the four prescriptive methods, analyses of predicted specific loudness, overall loudness, and bandwidth of cochlear excitation and effective audibility as well as speech intelligibility of the international long-term average speech spectrum (ILTASS) at an average conversational input level were completed. These analyses allow for the discussion of similarities and differences among the present-day prescriptive methods. Research Design: The impact of insertion gain differences among the methods is examined for seven hypothetical hearing loss configurations using models of loudness perception and speech intelligibility. Study Sample: Hearing loss configurations for adults of various types and degrees were selected, five of which represent sensorineural impairment and were used by Byrne et al; the other two hearing losses provide an example of mixed and conductive impairment. Data Collection and Analysis: Prescribed insertion gain data were calculated in 1/3-octave frequency bands for each of the seven hearing losses from the software application of each prescriptive method over multiple input levels. The insertion gain data along with a diffuse field-to-eardrum transfer function were used to calculate output levels at the eardrums of the hypothetical listeners. Levels of hearing loss and output were then used in the Moore and Glasberg loudness model and the ANSI S3.5-1997 Speech Intelligibility Index model. Results: NAL-NL2 and DSL m[i/o] provided comparable overall loudness of approximately 8 sones for the five sensorineural hearing losses for a 65 dB SPL ILTASS input. This loudness was notably less than that perceived by a normal-hearing person for the same input signal, 18.6 sones. NAL-NL2 and DSL m[i/o] also provided comparable predicted speech intelligibility in quiet and noise. CAMEQ2-HF provided a greater average loudness, similar to NAL-NL1, with more high-frequency bandwidth but no significant improvement to predicted speech intelligibility. Conclusions: Definite variation in prescribed insertion gain was present among the prescriptive methods. These differences when averaged across the hearing losses were, by and large, negligible with regard to predicted speech intelligibility at normal conversational speech levels. With regard to loudness, DSL m[i/o] and NAL-NL2 provided the least overall loudness, followed by CAMEQ2-HF and NAL-NL1 providing the most loudness. CAMEQ2-HF provided the most audibility at high frequencies; even so, the audibility became less effective for improving speech intelligibility as hearing loss severity increased.
88

Realistic Expectations for Speech Recognition with Digital Hearing Aid Devices Providing Acoustic Amplification and Noise Averting Microphones

Johnson, Earl E. 01 June 2018 (has links)
People with hearing loss (HL) often express a desire for the particular hearing device that will yield the best speech recognition. The problem with fulfilling that desire is that a vast number of hearing devices are available from which to choose. In recent years, medical device regulatory agencies have generally viewed hearing devices (i.e., hearing aids), particularly the hardware and even the software, as substantially equivalent. The purpose of this manuscript is to: 1) Synthesize a number of variables about the person, environment in which hearing occurs, as well as characteristics of the hearing aids that can impact speech recognition. 2) Describe a created tool entitled Realistic Expectations 2 (RE2), which has application to the clinical needs of estimating expected speech recognition with and without hearing aids. RE2 is available as a supplemental file to this manuscript and may be useful for comparing estimates against measures of speech recognition ability in addition to assisting with the explanation of the operation and limitations of hearing aids. When expected speech recognition is achieved, subsequent development of speech and language can continue based on circumstance, cognitive status, and cultural-specific learning, as well as personal and societal betterment efforts like education, rehabilitation, and therapy.
89

Printed Multiband Antennas for Slim Mobile Communication Devices

Lee, Cheng-Tse 26 April 2010 (has links)
In this dissertation, a series of printed multiband antennas for slim mobile communication devices are presented. The study mainly focuses on how to effectively enhance the impedance bandwidth. With the equivalent LC matching circuit integrated in the antennas, wide impedance bandwidth can be obtained without increasing the size of the antennas. Note that the equivalent matching circuit can be formed by the coupling strip and the shorting strip to generate capacitance and inductance, respectively. In addition, the effects on the user's hand, head and whole body will be analyized. Also, the issue of the hearing aid compatibility will be discussed in this dissertation.
90

Internal Mobile Phone Antenna with Distributed LC Matching Circuit for Eight-band LTE/WWAN Operation

Chen, Wei-Yu 09 June 2010 (has links)
In this thesis, an internal mobile phone antenna with a distributed matching circuit for eight-band LTE/WWAN operation is presented. By selecting proper dimensions of the distributed matching circuit, the bandwidth of the proposed antenna can be greatly enhanced. Good radiation characteristics are also obtained, and the proposed antenna occupies only 60 ¡Ñ 10 ¡Ñ 3 mm^3 and is very suitable for slim mobile phone applications. Effects of the human body including user¡¦s head and hand are also studied, and the SAR and HAC issues are simulated and analyzed in this thesis.

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