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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.
131

För en etisk utsägelseposition : ethos och persona i Asta Olivia Nordenhof Penge på lommen

Kalin, Martin January 2022 (has links)
I denna studie undersöks den känsla av författarnärvaro som präglar Asta Olivia Nordenhofs roman Penge på lommen. Genom att undersöka hur Nordenhofs ethos och persona förhåller sig till bokens berättartekniker, samt hur detta samverkar med berättarpåträngningar, är det möjligt att visa hur författaren, genom en paus i narrativet, förmedlar sin egen röst och sammansmälter sin litterära persona med sitt ethos. Detta resultat kontextualiseras genom att beskriva Nordenhofs litterära samtid i Danmark. Därigenom skapar uppsatsen förståelse för vilka etiska dimensioner som ryms i romanens berättartekniker, i synnerhet blickens ökande och minskande distans till romankaraktärerna. Avslutningsvis diskuteras författarnävaron utifrån blickens etiska aspekter.
132

Looking Outside of Self and Experience: Effects of Cognitive Distancing on Intrusive Thought Responses

Adut, Sarah Lily January 2019 (has links)
No description available.
133

Design and application of a novel Laser-Doppler Velocimeter for turbulence structural measurements in turbulent boundary layers

Lowe, K. Todd 20 November 2006 (has links)
An advanced laser-Doppler velocimeter is designed to acquire fully-resolved turbulence structural measurements in high Reynolds number two- and three-dimensional turbulent boundary layers. The new instrument combines, for the first time, new techniques allowing for the direct measurement of particle acceleration and sub-measurement-volume-scale position resolution so that second-order 3D particle trajectories may be measured at high repetitions. Using these measurements, several terms in the Reynolds stress transport equations may be directly estimated, giving new data for modeling and understanding the processes leading to the transport of turbulence in boundary layer flows. Due to the unique performance of the probe, many aspects of LDV instrumentation development were addressed. The LDV configuration was optimized for lowest uncertainties by considering the demanding applications of particle position and acceleration measurements. Low noise light detection and signal conditioning was specified for the three electronic channels. A high-throughput data acquisition system allows for exceptional burst rate acquisition. Signal detection and processing algorithms have been implemented which draw from previous techniques but also address distinctive problems with the current system. In short, the instrument was designed to advance the state-of-the-art in LDV systems. Measurements presented include turbulence dissipation rate and fluctuating velocity-pressure gradient correlations that have been measured in 2D and 3D turbulent boundary layers using the unique capabilities of the CompLDV--many of these measurements are the first of their kind ever acquired in high Reynolds number turbulent flows. The flat-plate turbulent boundary layer is studied at several momentum thickness Reynolds numbers up to 7500 to examine Reynolds numbers effects on terms such as the velocity-pressure gradient correlation and the dissipation rate in the Reynolds transport equations. Measurements are also presented in a pressure-driven three-dimensional turbulent boundary layer created upstream from a wing-body junction. The current results complement the extensive data from previous studies and provide even richer depth of knowledge on the most-completely-documented 3D boundary layer flow in existence. Further measurements include the wakes of three circular-cylinder protuberances submerged in a constant pressure turbulent boundary layer. / Ph. D.
134

Vers une stratégie robuste et efficace pour le contrôle des calculs par éléments finis en ingénierie mécanique / Towards a robust and effective strategy for the control of finite element computations in mechanical engineering

Pled, Florent 13 December 2012 (has links)
Ce travail de recherche vise à contribuer au développement de nouveaux outils d'estimation d'erreur globale et locale en ingénierie mécanique. Les estimateurs d'erreur globale étudiés reposent sur le concept d'erreur en relation de comportement à travers des techniques spécifiques de construction de champs admissibles, assurant l'aspect conservatif ou garanti de l'estimation. Une nouvelle méthode de construction de champs admissibles est mise en place et comparée à deux autres méthodes concurrentes, en matière de précision, coût de calcul et facilité d'implémentation dans les codes éléments finis. Une amélioration de cette nouvelle méthode hybride fondée sur une minimisation locale de l'énergie complémentaire est également proposée. Celle-ci conduit à l'introduction et à l'élaboration de critères géométriques et énergétiques judicieux, permettant un choix approprié des régions à sélectionner pour améliorer localement la qualité des champs admissibles. Dans le cadre des estimateurs d'erreur locale basés sur l'utilisation conjointe des outils d'extraction et des estimateurs d'erreur globale, deux nouvelles techniques d'encadrement de l'erreur en quantité d'intérêt sont proposées. Celles-ci sont basées sur le principe de Saint-Venant à travers l'emploi de propriétés spécifiques d'homothétie, afin d'améliorer la précision des bornes d'erreur locale obtenues à partir de la technique d'encadrement classique fondée sur l'inégalité de Cauchy-Schwarz. Les diverses études comparatives sont menées dans le cadre des problèmes d'élasticité linéaire en quasi-statique. Le comportement des différents estimateurs d'erreur est illustré et discuté sur des exemples numériques tirés d'applications industrielles. Les travaux réalisés constituent des éléments de réponse à la problématique de la vérification dans un contexte industriel. / This research work aims at contributing to the development of innovative global and goal-oriented error estimation tools applied to Computational Mechanics. The global error estimators considered rely on the concept of constitutive relation error through specific techniques for constructing admissible fields ensuring the recovery of strict and high-quality error estimates. A new hybrid method for constructing admissible stress fields is set up and compared to two other techniques with respect to three different criteria, namely the quality of associated error estimators, the computational cost and the simplicity of practical implementation into finite element codes. An enhanced version of this new technique based on local minimization of the complementary energy is also proposed. Judicious geometric and energetic criteria are introduced to select the relevant zones for optimizing the quality of the admissible fields locally. In the context of goal-oriented error estimation based on the use of both extraction techniques and global error estimators, two new improved bounding techniques are proposed. They lean on Saint-Venant's principle through specific homotheticity properties in order to obtain guaranteed and relevant bounds of better quality than with the classical bounding technique based on the Cauchy-Schwarz inequality. The various comparative studies are conducted on linear elasticity problems under quasi-static loading conditions. The behaviour of the different error estimators is illustrated and discussed through several numerical experiments carried out on industrial cases. The associated results may open up opportunities and help broaden the field of model verification for both academic research and industrial applications.
135

Die invloed van ekspressiewe skryfoefeninge op die werkende geheue van adolescente en jong volwassenes (The influence of expressive writing on the memory of adolescents and young adults

Swart, Johanna Catherina 12 1900 (has links)
Text in English / Abstracts in Afrikaans and English / Ekspressiewe skryfwerk (ES) – as ‘n metode van intervensie gemik op fisiese en geesteswelstand van deelnemers – word reeds vir ongeveer drie dekades ondersoek. Klein en Boals beweer met hul 2001-studie dat ES ook ‘n positiewe invloed uitoefen op die werkende geheue van individue. Met die huidige studie word die vraag of hierdie bevinding ook van toepassing is op adolessente en jong volwassenes van Suidelike Afrika ondersoek. Dié projek betrek aanvanklik skoolleerders (N = 44) en eerstejaar universiteitstudente (N = 83) in die Suid-Kaap en met die skryfoefeninge word ‘n komponent bygevoeg by een van die eksperimentele groepe waar kognitiewe insette saam met die emosionele onthulling verlang word. Die studie-resultate toon heelwat teenstrydighede, dog die positiewe invloed van ES op die werkspan word by ‘n goeie aantal eksperimentele groep deelnemers waargeneem. Vorige navorsing dui op ‘n verlaging in die voorkoms van indringer- en vermydingsgedagtes na ES tesame met verbeterde werkspan en hierdie verband word van nader beskou deur die huidige studie. Die moontlikheid dat woordtelling per minuut as informele meting van werkspan aanvaar kan word, sowel as die moontlike verband tussen gemoedsvlak en skryfkondisie word ook met die projek ondersoek. / During the past three decades expressive writing has been in the research spotlight as an effective method of intervention in the improvement of human well-being. In 2001 a study done by Klein and Boals claimed that expressive writing also has a positive influence on the working memory of the student participants. The current study investigates the influence of expressive writing on adolescents and young adults in the Southern Africa context. Solution-focused exercises, together with emotional expression during the writing sessions, add a cognitive component to the intervention which strive to create greater impact on working memory capacity (WMC). Previous research indicate that improvement in WMC goes hand in hand with the reduction in the prevalence of intrusive and avoidant thoughts. During the current project the relationship between working memory and these thoughts is investigated. Additionally the possibility of word count as informal measure for WMC are looked at as well as a possible association between mood level and writing condition. / Psychology / M.A. (Psychology)
136

Alojamento e deformação de plútons graníticos da extremidade nordeste da Suíte Intrusiva Cunhaporanga (Domínio Apiaí - Faixa Ribeira, PR) / Emplacement and deformation of granitic plutons from northeast of Cunhaporanga Intrusive Suite (Apiaí Domain - Ribeira Belt, PR)

Caltabeloti, Fabrizio Prior 29 April 2011 (has links)
Plútons graníticos (Patrimônio Santo Antônio, São Domingos, Ouro Verde e Santa Rita) alojados na porção nordeste da Suíte Intrusiva Cunhaporanga (c. 620-590 Ma) intrudiram metassedimentos pelíticos e carbonáticos de baixo grau metamórfico do Grupo Itaiacoca. Os plútons são isótropos, de coloração cinza a rósea e composição monzo- a sienogranítica, predominando granitóides porfiríticos grossos e, secundariamente, tipos inequigranulares a equigranulares. A cartografia regional mostrou que a foliação das rochas metassedimentares encaixantes mergulha dominantemente para NE e contém uma lineação (interseção, mineral) de direção NNW-SSE. A trama metamórfica das encaixantes assume progressivamente a direção NE-SW conforme se aproxima da zona de cisalhamento transcorrente de Itapirapuã, onde quartzo-milonitos verticalizados exibem uma cinemática sinistral. A trama dos plútons foi estudada pela técnica da anisotropia de suscetibilidade magnética (ASM). Foram amostradas 40 estações (300 espécimes) no granito porfírítico Patrimônio Santo Antônio, 7 estações (48 espécimes) no granito equigranular fino de São Domingos, 9 estações (67 espécimes) no granito inequigranular de Ouro Verde e 14 estações (92 espécimes) no granito porfiritico foliado de Santa Rita. A suscetibilidade magnética média (k) do granito Patrimônio Santo Antônio é da ordem de 23,29 x \'10 POT.-3\' SI, enquanto nos granitos Santa Rita (k = 11,85 mSI), São Domingos (k = 7,43 mSI) e Ouro Verde (k = 7,46 mSI) são menores. Por outro lado, a anisotropia magnética (P = \'k IND.max\'/\'k IND.min\', onde \'k IND.max\' > \'k IND.int\' > \'k IND.min\') é menor em Patrimônio Santo Antônio (P = 1,09 ± 0,04) do que no São Domingos (P = 1,21 ± 0,09), Ouro Verde (P = 1,19 ± 0,07) e Santa Rita (P = 1,23 ± 0,11). Estudos termomagnéticos e de magnetização remanente isotermal mostraram que as propriedades magnéticas dos granitoides são dominadas pela magnetita (pobre em Ti) e, secundariamente, Ti-hematita. Sulfetos de Fe (pirita, calcopirita) ocorrem como acessórios. Os óxidos de Fe estão frequentemente associados à titanita, biotita e anfibólio e suas microestruturas são tipicamente magmáticas, exceto no granito Santa Rita onde a microestrutura apresenta evidência de recristalização pós-magmática. A foliação magnética dos maciços graníticos mergulha suave a moderadamente e, no plúton Patrimônio Santo Antônio, exibe um padrão tipicamente dômico. A lineação magnética subhorizontal orienta-se na direção NNW-SSE paralelamente ao eixo do dobramento regional das rochas metassedimentares encaixantes. Esta característica indica que os granitos são sin-tectônicos a um evento deformacional cujo controle está aparentemente relacionado ao funcionamento das grandes transcorrências regionais de direção NE-SW. A ocorrência de domos graníticos (Patrimônio Santo Antônio) e elipsóides magnéticos dominantemente prolatos (São Domingos) sugerem que a trama NNW teria sido formada por uma tectônica que combina transcorrência e extensão. Uma idade concordante U-Pb (SHRIMP) em zircão de 589 ± 6 Ma, atribuída à cristalização do plúton Patrimônio Santo Antônio, indica que a deformação que afetou o granito no estado magmático bem como suas encaixantes ocorreu nos estágios finais da formação da Suíte Intrusiva Cunhaporanga. / Granite plutons located on the northeast of Cunhaporanga Intrusive Suite (Patrimônio Santo Antônio, Ouro Verde, São Domingos and Santa Rita) are emplaced into low grade metasedimentary rocks (Itaiacoca Group) of the Apiaí Domain (Ribeira Belt). Most of these plutons are isotropic with pinkish to grey colors and their compositions vary from monzogranite to sienogranite. They are usually porphyritic and locally inequigranular and equigranular. Regional mapping revealed that the foliation of the metasedimentary host rocks dips mainly to NE while the lineation (intersection, mineral) strikes in the NNW-SSE direction. The host rocks metamorphic fabric rotates progressively to become parallel to the NE-trending Itapirapuã transcurrent shear zone. Kinematic markers such as elongated quartz grains and mica-fish from quartz-milonites indicate the Itapirapuã shear records a sinistral movement. The fabric of the plutons was studied by anisotropy of magnetic susceptibility (AMS) technique. Forty sites (300 specimens) were sampled at the Patrimônio Santo Antônio granite, 7 sites (48 specimens) at São Domingos, 9 sites (67 specimens) at Ouro Verde and 14 sites (92 specimens) at Santa Rita granite. The mean of magnetic susceptibility (k) is higher in Patrimônio Santo Antônio granite (k = 23,29 x \'10 POT.-3\' SI) and lower in the granites of Santa Rita (k = 11,85 mSI), São Domingos (k = 7,43 mSI) and Ouro Verde (k = 7,46 mSI). In contrast the magnetic anisotropy (P) is lower in the Patrimônio Santo Antônio granite (P = 1,09 ± 0,04) and higher in the granites São Domingos (P = 1,21 ± 0,09), Ouro Verde (P = 1,19 ± 0,07) and Santa Rita (P = 1,23 ± 0,11). Thermomagnetic and Isothermal Remanent Magnetization (IRM) studies show that Ti-poor magnetite is the principal carrier of rock magnetic properties but that includes minor contributions of Ti-hematite. Iron oxides are frequently associated with titanite, biotite and amphibole. Microstructures are typically magmatic, except for Santa Rita granite which shows post-magmatic recrystallized microstructures. The magnetic foliation of granitic plutons dips smooth to moderately and for the Patrimônio Santo Antônio body it exhibits a typical dome pattern. The subhorizontal magnetic lineation strikes NNW-SSE parallel to regional folding axe of the metasedimentary rocks. This feature shows that the granites are syntectonic to a deformation event apparently connected to NE-trending transcurrent shears. The occurrence of a foliation dome in the Patrimônio Santo Antônio pluton and prolate magnetic ellipsoids in São Domingos pluton suggest that the NNW-trending structures includes, besides a strike-slip shear fabric, a component of extension that probably assisted the emplacement of the plutons. A U-Pb (SHRIMP) determination in the Patrimônio Santo Antônio zircons have produced a concordia age of 589 ± 6 Ma attributed to the crystallization of the granite. These results indicate that in the latest stages of the development of the Cunhaporanga Intrusive Suite the Apiaí Domain was submitted to a regional strain field recording transcurrent simple shear and extension.
137

Alojamento e deformação de plútons graníticos da extremidade nordeste da Suíte Intrusiva Cunhaporanga (Domínio Apiaí - Faixa Ribeira, PR) / Emplacement and deformation of granitic plutons from northeast of Cunhaporanga Intrusive Suite (Apiaí Domain - Ribeira Belt, PR)

Fabrizio Prior Caltabeloti 29 April 2011 (has links)
Plútons graníticos (Patrimônio Santo Antônio, São Domingos, Ouro Verde e Santa Rita) alojados na porção nordeste da Suíte Intrusiva Cunhaporanga (c. 620-590 Ma) intrudiram metassedimentos pelíticos e carbonáticos de baixo grau metamórfico do Grupo Itaiacoca. Os plútons são isótropos, de coloração cinza a rósea e composição monzo- a sienogranítica, predominando granitóides porfiríticos grossos e, secundariamente, tipos inequigranulares a equigranulares. A cartografia regional mostrou que a foliação das rochas metassedimentares encaixantes mergulha dominantemente para NE e contém uma lineação (interseção, mineral) de direção NNW-SSE. A trama metamórfica das encaixantes assume progressivamente a direção NE-SW conforme se aproxima da zona de cisalhamento transcorrente de Itapirapuã, onde quartzo-milonitos verticalizados exibem uma cinemática sinistral. A trama dos plútons foi estudada pela técnica da anisotropia de suscetibilidade magnética (ASM). Foram amostradas 40 estações (300 espécimes) no granito porfírítico Patrimônio Santo Antônio, 7 estações (48 espécimes) no granito equigranular fino de São Domingos, 9 estações (67 espécimes) no granito inequigranular de Ouro Verde e 14 estações (92 espécimes) no granito porfiritico foliado de Santa Rita. A suscetibilidade magnética média (k) do granito Patrimônio Santo Antônio é da ordem de 23,29 x \'10 POT.-3\' SI, enquanto nos granitos Santa Rita (k = 11,85 mSI), São Domingos (k = 7,43 mSI) e Ouro Verde (k = 7,46 mSI) são menores. Por outro lado, a anisotropia magnética (P = \'k IND.max\'/\'k IND.min\', onde \'k IND.max\' > \'k IND.int\' > \'k IND.min\') é menor em Patrimônio Santo Antônio (P = 1,09 ± 0,04) do que no São Domingos (P = 1,21 ± 0,09), Ouro Verde (P = 1,19 ± 0,07) e Santa Rita (P = 1,23 ± 0,11). Estudos termomagnéticos e de magnetização remanente isotermal mostraram que as propriedades magnéticas dos granitoides são dominadas pela magnetita (pobre em Ti) e, secundariamente, Ti-hematita. Sulfetos de Fe (pirita, calcopirita) ocorrem como acessórios. Os óxidos de Fe estão frequentemente associados à titanita, biotita e anfibólio e suas microestruturas são tipicamente magmáticas, exceto no granito Santa Rita onde a microestrutura apresenta evidência de recristalização pós-magmática. A foliação magnética dos maciços graníticos mergulha suave a moderadamente e, no plúton Patrimônio Santo Antônio, exibe um padrão tipicamente dômico. A lineação magnética subhorizontal orienta-se na direção NNW-SSE paralelamente ao eixo do dobramento regional das rochas metassedimentares encaixantes. Esta característica indica que os granitos são sin-tectônicos a um evento deformacional cujo controle está aparentemente relacionado ao funcionamento das grandes transcorrências regionais de direção NE-SW. A ocorrência de domos graníticos (Patrimônio Santo Antônio) e elipsóides magnéticos dominantemente prolatos (São Domingos) sugerem que a trama NNW teria sido formada por uma tectônica que combina transcorrência e extensão. Uma idade concordante U-Pb (SHRIMP) em zircão de 589 ± 6 Ma, atribuída à cristalização do plúton Patrimônio Santo Antônio, indica que a deformação que afetou o granito no estado magmático bem como suas encaixantes ocorreu nos estágios finais da formação da Suíte Intrusiva Cunhaporanga. / Granite plutons located on the northeast of Cunhaporanga Intrusive Suite (Patrimônio Santo Antônio, Ouro Verde, São Domingos and Santa Rita) are emplaced into low grade metasedimentary rocks (Itaiacoca Group) of the Apiaí Domain (Ribeira Belt). Most of these plutons are isotropic with pinkish to grey colors and their compositions vary from monzogranite to sienogranite. They are usually porphyritic and locally inequigranular and equigranular. Regional mapping revealed that the foliation of the metasedimentary host rocks dips mainly to NE while the lineation (intersection, mineral) strikes in the NNW-SSE direction. The host rocks metamorphic fabric rotates progressively to become parallel to the NE-trending Itapirapuã transcurrent shear zone. Kinematic markers such as elongated quartz grains and mica-fish from quartz-milonites indicate the Itapirapuã shear records a sinistral movement. The fabric of the plutons was studied by anisotropy of magnetic susceptibility (AMS) technique. Forty sites (300 specimens) were sampled at the Patrimônio Santo Antônio granite, 7 sites (48 specimens) at São Domingos, 9 sites (67 specimens) at Ouro Verde and 14 sites (92 specimens) at Santa Rita granite. The mean of magnetic susceptibility (k) is higher in Patrimônio Santo Antônio granite (k = 23,29 x \'10 POT.-3\' SI) and lower in the granites of Santa Rita (k = 11,85 mSI), São Domingos (k = 7,43 mSI) and Ouro Verde (k = 7,46 mSI). In contrast the magnetic anisotropy (P) is lower in the Patrimônio Santo Antônio granite (P = 1,09 ± 0,04) and higher in the granites São Domingos (P = 1,21 ± 0,09), Ouro Verde (P = 1,19 ± 0,07) and Santa Rita (P = 1,23 ± 0,11). Thermomagnetic and Isothermal Remanent Magnetization (IRM) studies show that Ti-poor magnetite is the principal carrier of rock magnetic properties but that includes minor contributions of Ti-hematite. Iron oxides are frequently associated with titanite, biotite and amphibole. Microstructures are typically magmatic, except for Santa Rita granite which shows post-magmatic recrystallized microstructures. The magnetic foliation of granitic plutons dips smooth to moderately and for the Patrimônio Santo Antônio body it exhibits a typical dome pattern. The subhorizontal magnetic lineation strikes NNW-SSE parallel to regional folding axe of the metasedimentary rocks. This feature shows that the granites are syntectonic to a deformation event apparently connected to NE-trending transcurrent shears. The occurrence of a foliation dome in the Patrimônio Santo Antônio pluton and prolate magnetic ellipsoids in São Domingos pluton suggest that the NNW-trending structures includes, besides a strike-slip shear fabric, a component of extension that probably assisted the emplacement of the plutons. A U-Pb (SHRIMP) determination in the Patrimônio Santo Antônio zircons have produced a concordia age of 589 ± 6 Ma attributed to the crystallization of the granite. These results indicate that in the latest stages of the development of the Cunhaporanga Intrusive Suite the Apiaí Domain was submitted to a regional strain field recording transcurrent simple shear and extension.
138

[pt] TRANSFERÊNCIA ULTRASSÔNICA DE ENERGIA E DADOS ATRAVÉS DE CAMADAS DE METAL E FLUIDO UTILIZANDO MODULAÇÃO EM FREQUÊNCIA / [en] ULTRASONIC ENERGY AND DATA TRANSFER THROUGH METAL AND FLUID LAYERS USING FREQUENCY MODULATION

RAPHAEL BOTELHO PEREIRA 18 July 2023 (has links)
[pt] A necessidade de transmitir energia e dados através de barreiras metálicas tem sido cada vez maior em aplicações industriais, onde não é possível a penetração de cabos elétricos, ou o uso de ondas eletromagnéticas, tais como, por exemplo, em sistemas de sensoriamento de cimentação em poços de petróleo. Ondas acústicas podem ser uma solução para esse problema, porque não são afetadas pelo efeito gaiola de Faraday, além de possuírem baixa atenuação ao atravessarem metais. Diversos esforços foram feitos para realizar a transmissão de dados através de camadas metálicas, com abordagens que variam em composição do canal acústico, taxa de transmissão, transmissão simultânea de dados e energia e complexidade dos circuitos empregados; existe, porém, carência de trabalhos que envolvam camadas metal-fluído-metal. Este trabalho apresenta uma possível solução utilizando ondas acústicas como meio de transportar energia e dados em um canal composto de barreiras com duas camadas metálicas e uma de fluído. Aqui propõe-se uma inovadora técnica de controle automático de ganho e um melhor aproveitamento da largura de banda do canal acústico, que permite maior taxa de transmissão de dados. É ainda proposta uma técnica para controle dinâmico da portadora enviada ao lado passivo do sistema. Inicialmente, foi feita uma análise de um modelo numérico, baseado em trabalhos anteriores, fundamentado na propagação de ondas acústicas e baseado na analogia acustoelétrica. Em seguida, desenvolveu-se um sistema eletrônico para receber / transmitir energia e dados digitais, modulados em frequência, de um lado ao outro do sistema. Por fim, análises experimentais foram feitas utilizando como canal acústico, um conjunto de duas placas planas de aço (de 5 mm) separadas por uma camada de fluído (de 100 mm) e dois transdutores alinhados axialmente, realizando a transferência de energia e dados digitais modulados em frequência. O sistema foi capaz de realizar a transferência de dados a uma taxa de 19200 bps e simultaneamente uma transferência de energia de 66 mW, com essa energia foi possível alimentar o modulo eletrônico e um sensor de pressão e temperatura. Durante os testes foi constatado um aproveitamento de 5,5 por cento da energia aplicada ao canal, e foi possível atingir uma taxa de erro de bit de 5 por cento em um teste com 2 h e 30 min de duração, utilizando o canal acústico com camadas de múltiplos materiais propostos. O sistema de controle de portadora funcionou adequadamente, permitindo uma redução de consumo de até 53 por cento. O controle automático de ganho permitiu uma redução de 50 por cento na taxa de erro de decodificação. Demonstra-se, então, a viabilidade de tais sistemas de controle propostos, os quais podem ser úteis em casos onde existam variações nas características acústicas do canal em questão que, em conjunto com a transferência não intrusiva, pode prover solução para sistemas de sensoriamento. / [en] The need for energy and data transmission through metallic barriers is increasing in industrial applications, where the penetration of electrical waves or the use of electrical waves is not possible. An example of such a scenario is the monitoring of cementing in wellbore applications. Acoustic waves are promising to solve this problem, since they are not affected by the Faraday cage effect, in addition, they present low attenuation when propagating in metals. Several efforts have been made to carry out data transmission through metallic layers, with approaches that vary in composition of the acoustic channel, transmission speed, simultaneous transmission of data and energy and the complexity of the circuits used, but there is a lack of works involving metal-fluid-metal layers. This work presents a possible solution using acoustic waves as a mean of transporting energy and data in a channel composed of barriers with two metallic layers and one fluid layer. Here, it is proposed a novel technique for automatic gain control and better use of the available bandwidth of the acoustic channel, which allows higher data transmission speed. Also, a technique for dynamic control of the carrier sent to the passive side of the system is proposed. Initially, an analysis with a numerical model was made, following previous works, which is based on the propagation of acoustic waves and relying on the acoustoelectric analogy. Then, an electronic system was developed to receive/transmit power and digital data, frequency modulated, from one side of the system to the other. Finally, experimental analyzes were performed using as an acoustic channel, a set of two flat steel plates (5 mm) separated by a fluid layer (100 mm) and a pairs of axially aligned transducers, performing the energy transfer and frequency modulated digital data. The system was able to transfer data at a rate of 19200 bps and simultaneously a transfer of energy of 66 mW, with this energy it was possible to feed the inside block module and a pressure and temperature sensor. During the tests, it was verified that 5.5 per cent of the energy applied to the channel was used, and it a bit error rate down to of 5 per cent was reached in a test with 2 h and 30 min of duration, using the multi-layered acoustic. The automatic carrier control system worked as expected and allowed one to reduce energy consumption in 53 per cent. The automatic gain control allowed one to reduce the error rate in 50 per cent. These control systems prove the feasibility of the proposed system and further show the usefulness of the system in scenarios that are subject to variations in the acoustic characteristics of the channel.

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