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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.
361

Terapia com placa oclusal com e sem guias anteriores de desoclusão em pacientes com disfunção temporomandibular e zumbido subjetivo / Occlusal splint therapy in the management of patients with TMD and subjective tinnitus

Venezian, Giovana Cherubini 27 April 2012 (has links)
O objetivo deste estudo foi avaliar o efeito de placas oclusais com guias anteriores de desoclusão e placas oclusais com contatos bilaterais e anteriores simultâneos durante os movimentos excursivos da mandíbula em pacientes com disfunção temporomandibular (DTM) e zumbido subjetivo. Foram avaliados 264 pacientes encaminhados para tratamento da DTM na FORP/USP e selecionados 32 mulheres com DTM muscular, associada ou não a DTM articular, e zumbido subjetivo que preencheram os critérios de inclusão. O diagnóstico da DTM foi realizado com o Research Diagnostic Criteria for Temporomadibular Disorders (RDC/TMD). As pacientes foram divididas randomicamente em dois grupos para utilizarem um dos dois tipos de placas. As avaliações incluíram dor à palpação, limiar de dor a pressão com algômetro, medidas da amplitude dos movimentos mandibulares, eletromiografia de superfície, relato da intensidade da dor e da loudness do zumbido em escala visual analógica (EVA) e das características do zumbido. Os pacientes também responderam a um questionário para quantificação da frequência e severidade dos sinais e sintomas de DTM (ProDTMMulti) e para a avaliação do impacto do zumbido no dia-a-dia (Tinnitus Handicap Inventory - THI). A avaliação eletromiográfica foi realizada em várias atividades com e sem placa oclusal (apertamento máximo voluntário, movimentos excursivos mandibulares, repouso e mastigação habitual) e comparada com um grupo de 13 mulheres assintomáticas. As avaliações foram realizadas inicialmente (A1), no dia de instalação das placas oclusais, após 60 dias da avaliação inicial (A2) e após 90 dias de uso da placa oclusal (A3). O período entre as avaliações A1 e A2 foi considerado um período controle. Os resultados mostraram uma significante melhora da dor relatada pelo pacientes e aumento da amplitude da abertura bucal sem dor nos dois grupos, sem diferença entre eles. A atividade eletromiográfica foi significativamente reduzida durante apertamento máximo voluntário com a placa oclusal em comparação com o apertamento em máxima intercuspidação habitual, para as demais atividades realizadas durante o exame não houve diferença significante. A avaliação do zumbido mostrou que em muitos pacientes houve remissão do sintoma após o tratamento com placa oclusal. Não houve diferença entre os grupos para todas as avaliações realizadas. Baseados nesses achados, pode-se concluir que o tratamento com ambas as placas promoveu melhora na sintomatologia dos pacientes, sem diferenças entre elas, e houve em muitos pacientes uma remissão do zumbido relatado durante o tratamento. / The aim of this study was to assess the effect of anterior guidance and bilateral balanced splints in patients with temporomandibular disorders (TMD) and subjective tinnitus. A total of 264 subjects referred for treatment of TMD in FORP/USP were evaluated and 32 women with muscular TMD with or without the diagnosis of articular TMD, who met the inclusion criteria, were selected. TMD diagnosis was performed according to Research Diagnostic Criteria for Temporomadibular Disorders (RDC/TMD). The patients were randomly divided into two groups: anterior guidance splint group and bilateral balanced splints group. The assessments included pain to palpation, pressure pain threshold with algometer, measurement of amplitude of mandibular movements, surface electromyography, pain intensity and loudness of tinnitus reports in visual analogue scale (VAS) and characteristics of tinnitus. The patients also answered a questionnaire to quantify the frequency and severity of signs and symptoms of TMD (ProDTMMulti) and to assess the impact of tinnitus on a day-to-day (Tinnitus Handicap Inventory - THI). The electromyography evaluation was performed in different activities with and without occlusal splint (maximum voluntary clenching, excursive jaw movements, resting and habitual chewing) and compared to a group of 13 asymptomatic women. The assessments were performed initially (A1), at the day of installation of the occlusal splints, after 60 days of the initial assessment (A2) and after 90 days of occlusal splint therapy (A3). The period between A1 and A2 assessments was considered a control period. The results showed a significant improvement in pain reported by patients and an increase in the amplitude of mouth opening without pain in both groups, without difference between them. The electromyographic activity was significantly reduced during maximum voluntary clenching with occlusal splint compared to clenching in maximal habitual intercuspation, to the other activities performed during the examination there was no significant difference. The tinnitus evaluation showed that in many patients there was remission of symptom after treatment with occlusal splint. There was no difference among groups for all assessments. Based on these findings it is possible to conclude that treatment with both splints promoted improvement in symptoms of patients, without differences among them, and many patients had a remission of reported tinnitus during the treatment.
362

Interface entre design e fonoaudiologia:  material instrucional impresso voltado aos usuários de  aparelho de amplificação sonora individual / Interface between design and audiology: printed instructional material for hearing aid users

Medina, Camila 22 February 2017 (has links)
Usuários de aparelhos de amplificação sonora individuais (AASI) apresentam dificuldades com relação ao uso e cuidados com o dispositivo, podendo levar a um impacto negativo na intervenção. Manuais de instrução do AASI, produzidos pelos fabricantes deste dispositivo, frequentemente apresentam baixa leiturabilidade e design pouco eficiente ao público alvo, tornando-os, muitas vezes, ineficazes. A presente pesquisa teve como objetivo desenvolver e avaliar um material gráfico instrucional sobre uso e cuidados com o AASI, voltado para as necessidades destes usuários. Para tal, foram realizados três estudos complementares. Estudo 1: Realização de grupo focal com 10 usuários de AASI (9 homens, 1 mulher, média 57,4 anos) para identificar informações que estes desejavam receber quanto ao manuseio do dispositivo e preferências quanto aos aspectos gráficos dos manuais. A gravação do grupo focal foi transcrita e a análise temática de conteúdo (Bardin, 2011) aplicada. Foram identificadas três categorias principais: AASI e molde auricular (59,8%), manual de instruções (25,3%) e perda auditiva (14,9%). Além do uso e cuidados com o AASI verificou-se a necessidade de incluir informações referentes ao diagnóstico audiológico, adaptação aos sinais amplificados e uso de estratégias de comunicação. Houve preferência por ilustrações a traço, fonte sem serifa e em tamanho maior. Sugere-se maior número de ilustrações acompanhadas de pouco texto, em impresso tamanho A5. Estudo 2: Efetuou-se o levantamento e análise de seis manuais de instrução de AASIs, de diferentes períodos históricos. Verificou-se que os aspectos gráficos dos manuais de instrução evoluíram de acordo com as tecnologias e movimentos artísticos da época. Ademais, observou-se que os manuais atuais apresentam deficiências gráficas como tamanho da fonte e do impresso considerados pequenos. Estudo 3: Foi realizado o redesign de um manual de instrução de AASI tipo retroauricular, de acordo com os resultados obtidos nos Estudos 1 e 2 e princípios do design. Este manual foi avaliado por 30 fonoaudiólogas (média 35,7 anos), com experiência no processo de seleção e adaptação de AASI, por meio de um formulário online contendo 22 itens. Pontuações altas foram obtidas quanto à qualidade e utilidade do manual na prática clínica. A eficiência das páginas para transmissão da informação foi analisada via escala likert de 5 pontos, sendo obtidas médias variando de 3,57±1,1 (Capa) a 4,70±0,84, (Como ligar e desligar o aparelho). Diferenças pequenas, porém significativas (p<0,05) foram encontradas entre as pontuações de algumas páginas sugerindo necessidade de readequação. Uma segunda versão do manual redesenhado foi analisada por cinco novos usuários (2 homens, 3 mulheres, média de idade 71 anos) de AASI, por meio de entrevista. Adequações como inversão de lugares entre títulos e subtítulos e exclusão de alguns conteúdos ocorreram após a entrevista. Diferentes etapas foram necessárias para o desenvolvimento de um material gráfico instrucional sobre uso e cuidados com o AASI. Faz-se necessária a condução de outros estudos para avaliação da usabilidade e eficácia deste manual redesenhado para a compreensão e retenção de informação. / Hearing aid (HA) users present difficulties regarding the use and care of their devices, which may lead to a negative impact on the intervention. Hearing aid booklets, developed by HA manufacturers, often have low readability levels and design inadequate to the target audience, rendering them ineffective. This investigation aimed to develop and assess a printed instructional material on HA use and care focused on their users needs. Three complementary studies were carried out. Study 1: A focus group with 10 HA users (9 men, 1 woman, mean age: 57.4 years) was executed to identify information they wanted to receive regarding hearing aid use and maintenance as well as their preferences relating to booklets graphic aspects. The focus group was recorded, transcribed and thematic content analysis was applied. Three main categories were identified: hearing aid and earmold (59.8%), HA booklet (25.3%) and hearing loss (14.9%). In addition to hearing aid use and maintenance it was necessary to include information regarding audiological diagnosis, adaptation to amplified signals and use of communication strategies. Preference was given to simple line drawings, larger sans-serif fonts and A5 printed format. The use of a greater number of illustrations accompanied by little text was suggested. Study 2: An analysis of six hearing aid printed instructional materials, from different historical periods, was carried out. It was verified that the graphical aspects of such materials evolved according to the technologies and artistic movements of the time. In addition, it was observed that current hearing aid booklets present graphical inadequacies such and small font sizes and format. Study 3: The redesign of a behind-the-ear hearing aid booklet was carried out, according to the results obtained in Studies 1 and 2 as well as good design principles. This booklet was assessed by 30 female audiologists (mean 35.7 years), with experience in hearing aid fitting, via a 22-item online form. High scores were obtained regarding booklets quality and usefulness in clinical practice. The efficiency of the booklets pages for transmitting of the information was assessed through a 5-points likert type scale - average scores ranging from 3.57±1.1 (Cover) to 4.70±0.84 (Turning the hearind aid on and off) were obtained. Small but significant differences (p <0.05) were found among the pages scores, thus suggesting the need for readjustment. A second version of the redesigned manual was analyzed by five new hearing aid users (2 men, 3 women, mean age 71 years) by means of an interview. Adequations such as repositioning titles and subtitles as well as the exclusion of some contents considered unnecessary by the participants occurred after the interview. Different steps were required for the development of a printed instructional material on hearing aid use and maintenance. Further studies are necessary to evaluate the usability and effectiveness of such material information comprehension and retention.
363

[en] ANISOTROPIC DIELECTRIC CORRUGATED CYLINDRICAL GUIDE / [pt] GUIA CILÍNDRICO CORRUGADO COM DIELÉTRICO ANISOTRÓPICO

KATHY CAMILA CARDOZO OSINSKI SENHORINI 25 June 2012 (has links)
[pt] Esta tese apresenta uma análise de uma estrutura de corneta cônica corrugada com dielétrico anisotrópico, com eixo óptico na direção axial da corneta. Esta configuração de corneta pode ser conseguida utilizando-se a estrutura de uma corneta corrugada com a adição de um cone dielétrico anisotrópico uniaxial. A anisotropia pode ser conseguida artificialmente dopando-se o material dielétrico isotrópico ou utilizando-se uma técnica de perfuração na direção axial do cone. Esta técnica de perfuração é sugerida e apresentada nesta Tese. Partindo-se da geometria definida, foram desenvolvidas as expressões dos campos transversais e o equacionamento para a obtenção das curvas características da estrutura. É apresentado ainda um estudo comparativo dos campos transversais com os casos degenerados já conhecidos de guias cilíndricos, entre eles, guia cilíndrico corrugado oco, guia cilíndrico metálico com bastão dielétrico, guia cilíndrico corrugado com bastão dielétrico isotrópico. As expressões para o cálculo dos campos radiados distantes foram obtidas para o guia cilíndrico corrugado com dielétrico anisotrópico. Em adição, expressões para o cálculo dos campos radiados distantes para a corneta cilíndrica corrugada com dielétrico anisotrópico com pequenos ângulos de abertura (flare angle) utilizando-se a aproximação por capa esférica foram obtidas e apresentadas. Estas expressões foram baseadas na terceira definição de Ludwig. Foram realizadas análises para estruturas já conhecidas geradas a partir da degeneração do caso mais geral apresentado nesta tese com o objetivo de validar a teoria desenvolvida e os resultados provaram a validade do material teórico desenvolvido. Finalmente, foi desenvolvida uma análise paramétrica da estrutura apresentada com o intuito de verificar o comportamento dos campos radiados e da polarização cruzada máxima em função da anisotropia e da frequência de operação. Verificou-se que a largura de feixe de meia potência foi pouco influenciada pela anisotropia do dielétrico e apresentou comportamento esperado em função da frequencia. A variação da máxima polarização cruzada em função da frequência foi estudada. Em determinados valores de permissividade e anisotropia, para a configuração considerada, foi alcançada a condição híbrida balanceada. Nesta condição a estrutura apresentou baixos níveis de máxima polarização cruzada em uma faixa larga de frequência. Comportamento este muito superior ao da corneta corrugada, corneta metálica com dielétrico e corneta corrugada com dielétrico isotrópico. / [en] This thesis presents an analysis of a corrugated conic horn structure with anisotropic dielectric. This dielectric cone is positioned inside the horn and has an optical axis in its longitudinal direction. This horn configuration can be obtained using the structure of corrugated horn and adding an anisotropic dielectric cone. The anisotropy can artificially be obtained by doping the isotropic dielectric or using a perforation technique. This perforation technique is suggested and presented in this Thesis. Expressions for the transverse fields and the propagation constant curves were developed considering this new geometry. It is also presented a comparative study of the degenerated transversal fields with well-known structures. These structures are: hollow cylindrical guide, corrugated cylindrical guide, cylindrical metallic guide with dielectric and corrugated cylindrical guide with dielectric. The expressions to calculate the radiated far fields were obtained for the corrugated cylindrical guide with anisotropic dielectric. In addition, expressions to calculate the radiated far fields for the corrugated cylindrical horn with anisotropic dielectric were developed and presented. These expressions considered horns with small flare angle and used the spherical cap approximation theory. All expressions considered the 3th Ludwig definition for the radiated far field. Far field analyses were conducted for well-known structures. These structures were obtained by degenerating the new configuration presented in this thesis and aimed to validate the theoretical developed theory. The results proved its validity. Finally, a parametric analysis was performed. This analysis considered, for a given structure configuration, the behavior of the radiated far fields and its maximum cross polar levels as a function of the anisotropy and frequency. It was verified that the dielectric anisotropy had very little effect on the half power beam width characteristic. The maximum cross polar level as a function of the frequency was analyzed. For some specific values of permittivity and anisotropy, for the considered configuration, the balanced hybrid condition was reached. In this condition the structure presented very low cross polar values in a large frequency band. This behavior is much more superior to the corrugated horn, dielectric horn and the isotropic dielectric corrugated horn.
364

Análise de guias culturais da Área de negociação à luz da teoria da Inteligência Cultural: o caso da cultura árabe / Analysis of cultural guides from the area of negotiation under the light of Cultural Intelligence\'s theory: the case of arab culture

Costa, Andréia Lopes da 14 September 2009 (has links)
Este trabalho traz um exame dos guias classificados como culturais, e elaborados especificamente para a área de comércio internacional. Procura verificar a qualidade das informações neles contida a respeito da cultura em geral e da cultura árabe em particular, e também sua eficácia no processo de contato intercultural, verificando se de fato cumprem seu papel de guiar o leitor rumo ao conhecimento das características culturais do país alvo, com a intenção de possibilitar e facilitar o contato entre diferentes culturas. O exame desses guias é feito a luz da Inteligência Cultural, conceito relativamente novo que propõe o desenvolvimento de habilidades e de flexibilidade para aprender e assimilar aspectos de uma cultura. / This work brings an examination of the guides classified as cultural guides, elaborated specifically for the area of international commerce. Its aim is to verify the quality of the information contained in them about culture in general and, the Arab culture particularly; and so its efficiency in the process of intercultural contact, verifying whether in fact they fulfill the role of guiding the reader onto the path of knowledge of cultural characteristics about a particular country, with the intention of making contact possible and facilitating the contact between different cultures. The examination of these guides is made through the theory of Cultural Intelligence, a concept relatively new which is centered on the development of skills and flexibility to learn and assimilate aspects of a new culture.
365

Simulation of Cerenkov radiation for second harmonic generation and experimental generation and experimental characterization of MNA/PMMA/quartz thin film waveguides.

January 1995 (has links)
by Lui Bong Chun, Richard. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references. / Abstract / Acknowledgment / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background for the Project --- p.1 / Chapter 1.1.1 --- Interests in Blue-Green Laser --- p.1 / Chapter 1.1.2 --- Progress of Blue-Green Laser --- p.2 / Chapter 1.2 --- The Aim of the Project --- p.3 / Chapter 1.3 --- Overview the Remaining Parts of this Thesis --- p.4 / Chapter 1.4 --- References --- p.6 / Chapter Chapter 2 --- Sum Frequency Generation --- p.8 / Chapter 2.1 --- Introduction --- p.8 / Chapter 2.2 --- Sum Frequency Generation --- p.8 / Chapter 2.2.1 --- Theoretical Background for Sum Frequency Generation --- p.9 / Chapter 2.2.2 --- The Coupled Wave Equations for SFG --- p.13 / Chapter 2.2.3 --- Phase Matching Considerations --- p.16 / Chapter 2.3 --- References --- p.18 / Chapter Chapter 3 --- Cerenkov Radiation --- p.19 / Chapter 3.1 --- Introduction --- p.19 / Chapter 3.2 --- The Properties of Cerenkov Radiation by Using TM Mode --- p.21 / Chapter 3.2.1 --- Refractive Index Notation --- p.23 / Chapter 3.2.2 --- Fundamental Wave TM Guides Mode --- p.23 / Chapter 3.2.3 --- Second Harmonic TM Radiation Mode --- p.24 / Chapter 3.2.4 --- Efficiency of SHG --- p.25 / Chapter 3.3 --- Simplified Model Analysis of Cerenkov Radiation in TE Mode --- p.29 / Chapter 3.4 --- Simulation --- p.33 / Chapter 3.4.1 --- Modeling the LiNb03 --- p.33 / Chapter 3.4.2 --- Modeling an Asymmetric Slab Waveguide ´ؤPMMA doped with MNA on Fused Quartz --- p.37 / Chapter 3.4.3 --- Modeling a Symmetric Slab Waveguide ´ؤPMMA doped with MNA on Fused Quartz --- p.42 / Chapter 3.5 --- References --- p.47 / Chapter Chapter 4 --- Ellipsometry --- p.49 / Chapter 4.1 --- Introduction --- p.49 / Chapter 4.2 --- General Principles --- p.49 / Chapter 4.3 --- Basic Operation --- p.50 / Chapter 4.4 --- The Optical Constants of the Bulk Materials --- p.51 / Chapter 4.5 --- Calculation the Refractive Index of the Substrates --- p.53 / Chapter 4.6 --- Ellipsometric Theory for the Thin Film --- p.57 / Chapter 4.7 --- Measurement the Refractive Index and the Thickness of the Thin Film --- p.59 / Chapter 4.7.1 --- Data --- p.62 / Chapter 4.7.2 --- Discussions --- p.73 / Chapter 4.8 --- Calculation the Refractive Index of the thin Film by Considering as a Bulk Material --- p.78 / Chapter 4.9 --- References --- p.80 / Chapter Chapter 5 --- Prism Coupling --- p.81 / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.2 --- Coupling of a Plane Wave --- p.82 / Chapter 5.3 --- Numerical Approach for the Calculation of the Coupling Efficiency --- p.85 / Chapter 5.4 --- Experiment --- p.88 / Chapter 5.4.1 --- Experimental Setup --- p.88 / Chapter 5.4.2 --- Experimental Result and Discussions --- p.90 / Chapter 5.5 --- References --- p.92 / Chapter Chapter 6 --- Conclusion --- p.93 / Chapter Chapter 7 --- Future Plans --- p.96 / Chapter 7.1 --- Simplified Model of Corona Poling --- p.96 / Chapter 7.2 --- Advanced Models of Poling --- p.98 / Chapter 7.2.1 --- Slab Waveguide --- p.98 / Chapter 7.2.2 --- Channel Waveguide --- p.99 / Chapter 7.3 --- References --- p.100 / Chapter Appendix 1 --- Materials' Descriptions --- p.A-l / Chapter A.1.1 --- 2-Methyl-4-Nitoaniline --- p.A-1 / Chapter A.1.2 --- Poly ( Methyl Methacrylate ) --- p.A-3 / Chapter A.1.3 --- References --- p.A-4 / Chapter Appendix 2 --- Fabrication Procedures --- p.A-5 / Chapter A.2.1 --- Cleaning the Apparatus --- p.A-5 / Chapter A.2.2 --- Cleaning the Substrate --- p.A-5 / Chapter A.2.3 --- Thin film Fabrication --- p.A-5 / Chapter A.2.4 --- Thin Film Removal --- p.A-6 / Chapter A.2.5 --- References --- p.A-6 / Chapter Appendix 3 --- Alpha Step --- p.A-7 / Chapter A.3.1 --- Introduction --- p.A-7 / Chapter A.3.2 --- Experimental Setup --- p.A-8 / Chapter A.3.3 --- Experimental Results --- p.A-9 / Chapter A.3.3.1 --- Thin Film of PMMA without Dopant --- p.A-9 / Chapter A.3.3.2 --- Thin Film of PMMA doped with MNA --- p.A-19 / Chapter A.3.4 --- Discussions --- p.A-27 / Chapter A.3.5 --- References --- p.A-28 / Chapter Appendix 4 --- Scanning Electron Microscope --- p.A-29 / Chapter A.4.1 --- Scanning Electron Microscope --- p.A-29 / Chapter A.4.2 --- Reference --- p.A-30 / Chapter Appendix 5 --- Gaussian Beam & Coordinate System Transformation --- p.A-31 / Chapter A.5.1 --- Gaussian Beam in a Homogeneous Medium --- p.A-31 / Chapter A.5.2 --- Transformation of the Coordinate Systems --- p.A-32 / Chapter A.5.3 --- Reference --- p.A-32 / Chapter Appendix 6 --- Waist Size Measurement of Gaussian Beam --- p.A-33 / Chapter A.6.1 --- Waist Size Measurement of Gaussian Beam --- p.A-33 / Chapter A.6.2 --- References --- p.A-34 / Chapter Appendix 7 --- Quasi Phase Matching --- p.A-35 / Chapter A. 7.1 --- Introduction --- p.A-35 / Chapter A.7.2 --- Basic Concept of QPM --- p.A-36 / Chapter A.7.3 --- References --- p.A-38 / Chapter Appendix 8 --- Program Listing --- p.A-41 / Chapter A.8.1 --- Program Listing ( Chapter 3 ) --- p.A-41 / Chapter A.8.1.1 --- Program 3.1 (transcendental.m ) --- p.A-41 / Chapter A.8.1.2 --- Program 3.2 (linbo3.m) --- p.A-42 / Chapter A.8.2 --- Program Listing ( Chapter 4 ) --- p.A-45 / Chapter A.8.2.1 --- Program 4.1 ( ellipsometry.m ) --- p.A-45 / Chapter A.8.3 --- Program Listing ( Chapter 5 ) --- p.A-47 / Chapter A.8.3.1 --- Program 5.1 ( parameter.m ) --- p.A-47 / Chapter A.8.3.2 --- Program 5.2 ( coupling.m ) --- p.A-49 / Chapter A.8.3.3 --- Program 5.3 ( v_3_amp.m ) --- p.A-50 / Chapter A.8.3.4 --- Program 5.4 ( input_profile.m ) --- p.A-51
366

III-V semiconductor integrated optical waveguides and their applications.

January 1995 (has links)
by Chan Lai Yin Simon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references. / Chapter Chapter 1: --- Introduction / Chapter 1.1 --- Background --- p.1-2 / Chapter 1.2 --- Properties of the InGaAsP quaternary alloy on InP substrate --- p.2 / Chapter 1.2.1 --- Physical Properties of In1-xGaxASyP1-y on InP substrate --- p.3-4 / Chapter 1.2.2 --- Optical Properties of In1-xGaxASyP1-y on InP substrate --- p.4-7 / Chapter 1.2.3 --- Nonlinear Optical Property of InGaAsP --- p.7-9 / Chapter 1.3 --- Fabrication of InGaAsP/InP rib waveguide / Chapter 1.3.1 --- Epitaxial Growth of In1-xGaxASyP1-y on InP substrate by MOCVD --- p.9 / Chapter 1.3.2 --- Etching of the five layer In1-xGaxASyP1-y slab waveguide --- p.9-12 / Chapter 1.4 --- Overview of the thesis --- p.12-13 / References --- p.13-15 / Chapter Chapter 2: --- Modal analysis of the single mode III-V semiconductor waveguidesin multi-layer rib structure by Effective Index Method / Chapter 2.1 --- Introduction --- p.16-17 / Chapter 2.2 --- Modal analysis of the rib waveguides --- p.17-27 / Chapter 2.3 --- Optical Confinement in rib waveguide --- p.28-30 / Chapter 2.4 --- Conclusions and discussions --- p.30-31 / References --- p.31-33 / Chapter Chapter 3: --- Ultrashort Pulsewidth Measurement Part I / Chapter 3.1 --- Introduction --- p.34 / Chapter 3.2 --- Pulsewidth measurement by streak camera --- p.34-37 / Chapter 3.3 --- Pulsewidth measurement by nonlinear autocorrelation --- p.37-40 / Chapter 3.3.1 --- Second Harmonic Generation Autocorrelator --- p.40-43 / Chapter 3.3.2 --- Two Photon Fluorescence Autocorrelator --- p.43-44 / Chapter 3.4 --- Two Photon Absorption Waveguide Autocorrelator --- p.45 / Chapter 3.4.1 --- TPA theory --- p.45-48 / Chapter 3.4.2 --- Autocorrelation Measurement by TPA in InGaAsP Waveguide --- p.48-51 / Chapter 3.4.3 --- The Estimated performance of the TPA Waveguide Autocorrelator --- p.52 / References --- p.52-57 / Chapter Chapter 4: --- Ultrashort Pulsewidth Measurement Part II: High Sensitivity Two Photon Absorption InGaAsP Waveguide Autocorrelator for Low Power Pulsewidth Measurement of 1.55μm Waveguide Pulses / Chapter 4.1 --- Introduction --- p.58-60 / Chapter 4.2 --- Waveguide structures --- p.60 / Chapter 4.3 --- Practical Implementation of the TPA Waveguide Autocorrelator / Chapter 4.3.1 --- Mirror arrangement for the delay system --- p.61 -63 / Chapter 4.3.2 --- Alignment and Coupling of the InGaAsP/InP Waveguide --- p.63-64 / Chapter 4.3.3 --- TPA photocurrent detection --- p.64-65 / Chapter 4.4 --- Experimental results --- p.65-67 / Chapter 4.4.1 --- Pulsewidth measurement of the TPA InGaAsP waveguide autocorrelator --- p.67-71 / Chapter 4.4.2 --- Spectral analysis by the TPA InGaAsP waveguide autocorrelator --- p.71 -73 / Chapter 4.5 --- Conclusions and discussions --- p.73-75 / References --- p.75-78 / Chapter Chapter 5: --- Picosecond Pulses Generation by Colliding-Pulse Mode-locking of a Fabry-Perot Laser Diode with an Intra-cavity Gradual Degradation Defect / Chapter 5.1 --- Introduction --- p.79-80 / Chapter 5.2 --- Gain-switching --- p.80-84 / Chapter 5.3 --- Colliding Pulse Mode-locking --- p.84-85 / Chapter 5.3.1 --- Degradation of diode laser --- p.85-86 / Chapter 5.3.2 --- CPM Theory --- p.86-89 / Chapter 5.3.3 --- Experimental results --- p.89-92 / Chapter 5.4 --- Conclusions and discussions --- p.92-93 / References --- p.94-98 / Chapter Chapter 6: --- Conclusions / Chapter 6.1 --- Summary of the Research / Chapter 6.1.1 --- Theoretical Results --- p.99-100 / Chapter 6.1.2 --- Experimental Results --- p.101-104 / Chapter 6.2 --- Future Development / Chapter 6.2.1 --- Improvement of the TPA InGaAsP waveguide autocorrelator --- p.105 / Chapter 6.2.2 --- Future development of III-V semiconductor waveguides --- p.105-107 / References --- p.107-108 / Appendix --- p.109-121
367

UHF propagation channel characterization for tunnel microcellular and personal communications.

January 1996 (has links)
by Yue Ping Zhang. / Publication date from spine. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 194-200). / DEDICATION / ACKNOWLEDGMENTS / Chapter / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Brief Description of Tunnels --- p.1 / Chapter 1.2 --- Review of Tunnel Imperfect Waveguide Models --- p.2 / Chapter 1.3 --- Review of Tunnel Geometrical Optical Model --- p.4 / Chapter 1.4 --- Review of Tunnel Propagation Experimental Results --- p.6 / Chapter 1.5 --- Review of Existing Tunnel UHF Radio Communication Systems --- p.13 / Chapter 1.6 --- Statement of Problems to be Studied --- p.15 / Chapter 1.7 --- Organization --- p.15 / Chapter 2 --- Propagation in Empty Tunnels --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.2 --- Propagation in Empty Tunnels --- p.18 / Chapter 2.2.1 --- The Imperfect Empty Straight Rectangular Waveguide Model --- p.19 / Chapter 2.2.2 --- The Hertz Vectors for Empty Straight Tunnels --- p.20 / Chapter 2.2.3 --- The Propagation Modal Equations for Empty Straight Tunnels --- p.23 / Chapter 2.2.4 --- The Propagation Characteristics of Empty Straight Tunnels --- p.26 / Chapter 2.2.5 --- Propagation Numerical Results in Empty Straight Tunnels --- p.30 / Chapter 2.3 --- Propagation in Empty Curved Tunnels --- p.36 / Chapter 2.3.1 --- The Imperfect Empty Curved Rectangular Waveguide Model --- p.37 / Chapter 2.3.2 --- The Hertz Vectors for Empty Curved Tunnels --- p.39 / Chapter 2.3.3 --- The Propagation Modal Equations for Empty Curved Tunnels --- p.41 / Chapter 2.3.4 --- The Propagation Characteristics of Empty Curved Tunnels --- p.43 / Chapter 2.2.5 --- Propagation Numerical Results in Empty Curved Tunnels --- p.47 / Chapter 2.4 --- Summary --- p.50 / Chapter 3 --- Propagation in Occupied Tunnels --- p.53 / Chapter 3.1 --- Introduction --- p.53 / Chapter 3.2 --- Propagation in Road Tunnels --- p.53 / Chapter 3.2.1 --- The Imperfect Partially Filled Rectangular Waveguide Model --- p.54 / Chapter 3.2.2 --- The Scalar Potentials for Road tunnels --- p.56 / Chapter 3.2.3 --- The Propagation Modal Equations for Road Tunnels --- p.59 / Chapter 3.2.4 --- Propagation Numerical Results in Road Tunnels --- p.61 / Chapter 3.3 --- Propagation in Railway Tunnels --- p.64 / Chapter 3.3.1 --- The Imperfect Periodically Loaded Rectangular Waveguide Model --- p.65 / Chapter 3.3.2 --- The Surface Impedance Approximation --- p.66 / Chapter 3.3.2.1 --- The Surface Impedance of a Semi-infinite Lossy Dielectric Medium --- p.66 / Chapter 3.3.2.2 --- The Surface Impedance of a Thin Lossy Dielectric Slab --- p.67 / Chapter 3.3.2.3 --- The Surface Impedance of a Three-layered Half Space --- p.69 / Chapter 3.3.2.4 --- The Surface Impedance of the Sidewall of a Train in a Tunnel --- p.70 / Chapter 3.3.3 --- The Hertz Vectors for Railway Tunnels --- p.71 / Chapter 3.3.4 --- The Propagation Modal Equations for Railway Tunnels --- p.73 / Chapter 3.3.5 --- The Propagation Characteristics of Railway Tunnels --- p.76 / Chapter 3.3.6 --- Propagation Numerical Results in Railway Tunnels --- p.78 / Chapter 3.4 --- Propagation in Mine Tunnels --- p.84 / Chapter 3.4.1 --- The Imperfect periodically Loaded Rectangular Waveguide Model --- p.85 / Chapter 3.4.2 --- The Hertz Vectors for Mine Tunnels --- p.86 / Chapter 3.4.3 --- The Propagation modal Equations for Mine Tunnels --- p.88 / Chapter 3.4.4 --- The Propagation Characteristics of Mine Tunnels --- p.95 / Chapter 3.4.5 --- Propagation Numerical Results in Mine Tunnels --- p.96 / Chapter 3.5 --- Summary --- p.97 / Chapter 4 --- Statistical and Deterministic Models of Tunnel UHF Propagation --- p.100 / Chapter 4.1 --- Introduction --- p.100 / Chapter 4.2 --- Statistical Model of Tunnel UHF Propagation --- p.100 / Chapter 4.2.1 --- Experiments --- p.101 / Chapter 4.2.1.1 --- Experimental Set-ups --- p.102 / Chapter 4.2.1.2 --- Experimental Tunnels --- p.104 / Chapter 4.2.1.3 --- Experimental Techniques --- p.106 / Chapter 4.2.2 --- Statistical Parameters --- p.109 / Chapter 4.2.2.1 --- Parameters to Characterize Narrow Band Radio Propagation Channels --- p.109 / Chapter 4.2.2.2 --- Parameters to Characterize Wide Band Radio Propagation Channels --- p.111 / Chapter 4.2.3 --- Propagation Statistical Results and Discussion --- p.112 / Chapter 4.2.3.1 --- Tunnel Narrow Band Radio Propagation Characteristics --- p.112 / Chapter 4.2.3.1.1 --- Power Distance Law --- p.114 / Chapter 4.2.3.1.2 --- The Slow Fading Statistics --- p.120 / Chapter 4.2.3.1.3 --- The Fast Fading Statistics --- p.122 / Chapter 4.2.3.2 --- Tunnel Wide Band Radio Propagation Characteristics --- p.125 / Chapter 4.2.3.2.1 --- RMS Delay Spread --- p.126 / Chapter 4.2.3.2.2 --- RMS Delay Spread Statistics --- p.130 / Chapter 4.3 --- Deterministic Model of Tunnel UHF Propagation --- p.132 / Chapter 4.3.1 --- The Tunnel Geometrical Optical Propagation Model --- p.134 / Chapter 4.3.2 --- The Tunnel Impedance Uniform Diffracted Propagation Model --- p.141 / Chapter 4.3.2.1 --- Determination of Diffraction Points --- p.146 / Chapter 4.3.2.2 --- Diffraction Coefficients for Impedance Wedges --- p.147 / Chapter 4.3.3 --- Comparison with Measurements --- p.151 / Chapter 4.3.3.1 --- Narrow Band Comparison of Simulated and Measured Results --- p.151 / Chapter 4.3.3.1.1 --- Narrow Band Propagation in Empty Straight Tunnels --- p.151 / Chapter 4.3.3.1.2 --- Narrow Band Propagation in Curved or Obstructed Tunnels --- p.154 / Chapter 4.3.3.2 --- Wide Band Comparison of Simulated and Measured Results --- p.158 / Chapter 4.3.3.2.1 --- Wide Band Propagation in Empty Straight Tunnels --- p.159 / Chapter 4.3.3.2.2 --- Wide Band Propagation in an Obstructed Tunnel --- p.163 / Chapter 4.4 --- Summary --- p.165 / Chapter 5 --- Propagation in Tunnel and Open Air Transition Region --- p.170 / Chapter 5.1 --- Introduction --- p.170 / Chapter 5.2 --- Radiation of Radio Waves from a Rectangular Tunnel into Open Air --- p.171 / Chapter 5.2.1 --- Radiation Formulation Using Equivalent Current Source Concept --- p.171 / Chapter 5.2.2 --- Radiation Numerical Results --- p.175 / Chapter 5.3 --- Propagation Characteristics of UHF Radio Waves in Cuttings --- p.177 / Chapter 5.3.1 --- The Attenuation Constant due to the Absorption --- p.178 / Chapter 5.3.2 --- The Attenuation Constant due to the Roughness of the Sidewalls --- p.182 / Chapter 5.3.3 --- The Attenuation Constant due to the tilts of the Sidewalls --- p.183 / Chapter 5.3.4 --- Propagation Numerical Results in Cuttings --- p.184 / Chapter 5.4 --- Summary --- p.187 / Chapter 6 --- Conclusion and Recommendation for Future Work --- p.189 / APPENDIX --- p.193 / The Approximate Solution of a Transcendental Equation --- p.193 / REFERENCES --- p.194
368

Interface entre design e fonoaudiologia:  material instrucional impresso voltado aos usuários de  aparelho de amplificação sonora individual / Interface between design and audiology: printed instructional material for hearing aid users

Camila Medina 22 February 2017 (has links)
Usuários de aparelhos de amplificação sonora individuais (AASI) apresentam dificuldades com relação ao uso e cuidados com o dispositivo, podendo levar a um impacto negativo na intervenção. Manuais de instrução do AASI, produzidos pelos fabricantes deste dispositivo, frequentemente apresentam baixa leiturabilidade e design pouco eficiente ao público alvo, tornando-os, muitas vezes, ineficazes. A presente pesquisa teve como objetivo desenvolver e avaliar um material gráfico instrucional sobre uso e cuidados com o AASI, voltado para as necessidades destes usuários. Para tal, foram realizados três estudos complementares. Estudo 1: Realização de grupo focal com 10 usuários de AASI (9 homens, 1 mulher, média 57,4 anos) para identificar informações que estes desejavam receber quanto ao manuseio do dispositivo e preferências quanto aos aspectos gráficos dos manuais. A gravação do grupo focal foi transcrita e a análise temática de conteúdo (Bardin, 2011) aplicada. Foram identificadas três categorias principais: AASI e molde auricular (59,8%), manual de instruções (25,3%) e perda auditiva (14,9%). Além do uso e cuidados com o AASI verificou-se a necessidade de incluir informações referentes ao diagnóstico audiológico, adaptação aos sinais amplificados e uso de estratégias de comunicação. Houve preferência por ilustrações a traço, fonte sem serifa e em tamanho maior. Sugere-se maior número de ilustrações acompanhadas de pouco texto, em impresso tamanho A5. Estudo 2: Efetuou-se o levantamento e análise de seis manuais de instrução de AASIs, de diferentes períodos históricos. Verificou-se que os aspectos gráficos dos manuais de instrução evoluíram de acordo com as tecnologias e movimentos artísticos da época. Ademais, observou-se que os manuais atuais apresentam deficiências gráficas como tamanho da fonte e do impresso considerados pequenos. Estudo 3: Foi realizado o redesign de um manual de instrução de AASI tipo retroauricular, de acordo com os resultados obtidos nos Estudos 1 e 2 e princípios do design. Este manual foi avaliado por 30 fonoaudiólogas (média 35,7 anos), com experiência no processo de seleção e adaptação de AASI, por meio de um formulário online contendo 22 itens. Pontuações altas foram obtidas quanto à qualidade e utilidade do manual na prática clínica. A eficiência das páginas para transmissão da informação foi analisada via escala likert de 5 pontos, sendo obtidas médias variando de 3,57±1,1 (Capa) a 4,70±0,84, (Como ligar e desligar o aparelho). Diferenças pequenas, porém significativas (p<0,05) foram encontradas entre as pontuações de algumas páginas sugerindo necessidade de readequação. Uma segunda versão do manual redesenhado foi analisada por cinco novos usuários (2 homens, 3 mulheres, média de idade 71 anos) de AASI, por meio de entrevista. Adequações como inversão de lugares entre títulos e subtítulos e exclusão de alguns conteúdos ocorreram após a entrevista. Diferentes etapas foram necessárias para o desenvolvimento de um material gráfico instrucional sobre uso e cuidados com o AASI. Faz-se necessária a condução de outros estudos para avaliação da usabilidade e eficácia deste manual redesenhado para a compreensão e retenção de informação. / Hearing aid (HA) users present difficulties regarding the use and care of their devices, which may lead to a negative impact on the intervention. Hearing aid booklets, developed by HA manufacturers, often have low readability levels and design inadequate to the target audience, rendering them ineffective. This investigation aimed to develop and assess a printed instructional material on HA use and care focused on their users needs. Three complementary studies were carried out. Study 1: A focus group with 10 HA users (9 men, 1 woman, mean age: 57.4 years) was executed to identify information they wanted to receive regarding hearing aid use and maintenance as well as their preferences relating to booklets graphic aspects. The focus group was recorded, transcribed and thematic content analysis was applied. Three main categories were identified: hearing aid and earmold (59.8%), HA booklet (25.3%) and hearing loss (14.9%). In addition to hearing aid use and maintenance it was necessary to include information regarding audiological diagnosis, adaptation to amplified signals and use of communication strategies. Preference was given to simple line drawings, larger sans-serif fonts and A5 printed format. The use of a greater number of illustrations accompanied by little text was suggested. Study 2: An analysis of six hearing aid printed instructional materials, from different historical periods, was carried out. It was verified that the graphical aspects of such materials evolved according to the technologies and artistic movements of the time. In addition, it was observed that current hearing aid booklets present graphical inadequacies such and small font sizes and format. Study 3: The redesign of a behind-the-ear hearing aid booklet was carried out, according to the results obtained in Studies 1 and 2 as well as good design principles. This booklet was assessed by 30 female audiologists (mean 35.7 years), with experience in hearing aid fitting, via a 22-item online form. High scores were obtained regarding booklets quality and usefulness in clinical practice. The efficiency of the booklets pages for transmitting of the information was assessed through a 5-points likert type scale - average scores ranging from 3.57±1.1 (Cover) to 4.70±0.84 (Turning the hearind aid on and off) were obtained. Small but significant differences (p <0.05) were found among the pages scores, thus suggesting the need for readjustment. A second version of the redesigned manual was analyzed by five new hearing aid users (2 men, 3 women, mean age 71 years) by means of an interview. Adequations such as repositioning titles and subtitles as well as the exclusion of some contents considered unnecessary by the participants occurred after the interview. Different steps were required for the development of a printed instructional material on hearing aid use and maintenance. Further studies are necessary to evaluate the usability and effectiveness of such material information comprehension and retention.
369

Surface acoustic wave gratings of finite width

Merab, André Antoine January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by André Antoine Merab. / M.S.
370

An integrated optics pulse shaping device

Shepard, Scott Roger January 1981 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by Scott Roger Shepard. / M.S.

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