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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.
351

Characterizing and controlling program behavior using execution-time variance

Kumar, Tushar 27 May 2016 (has links)
Immersive applications, such as computer gaming, computer vision and video codecs, are an important emerging class of applications with QoS requirements that are difficult to characterize and control using traditional methods. This thesis proposes new techniques reliant on execution-time variance to both characterize and control program behavior. The proposed techniques are intended to be broadly applicable to a wide variety of immersive applications and are intended to be easy for programmers to apply without needing to gain specialized expertise. First, we create new QoS controllers that programmers can easily apply to their applications to achieve desired application-specific QoS objectives on any platform or application data-set, provided the programmers verify that their applications satisfy some simple domain requirements specific to immersive applications. The controllers adjust programmer-identified knobs every application frame to effect desired values for programmer-identified QoS metrics. The control techniques are novel in that they do not require the user to provide any kind of application behavior models, and are effective for immersive applications that defy the traditional requirements for feedback controller construction. Second, we create new profiling techniques that provide visibility into the behavior of a large complex application, inferring behavior relationships across application components based on the execution-time variance observed at all levels of granularity of the application functionality. Additionally for immersive applications, some of the most important QoS requirements relate to managing the execution-time variance of key application components, for example, the frame-rate. The profiling techniques not only identify and summarize behavior directly relevant to the QoS aspects related to timing, but also indirectly reveal non-timing related properties of behavior, such as the identification of components that are sensitive to data, or those whose behavior changes based on the call-context.
352

Emittance preservation and luminosity tuning in future linear colliders

Eliasson, Peder January 2008 (has links)
<p>The future International Linear Collider (ILC) and Compact Linear Collider (CLIC) are intended for precision measurements of phenomena discovered at the Large Hadron Collider (LHC) and also for the discovery of new physics. In order to offer optimal conditions for such experiments, the new colliders must produce very-high-luminosity collisions at energies in the TeV regime.</p><p>Emittance growth caused by imperfections in the main linacs is one of the factors limiting the luminosity of CLIC and ILC. In this thesis, various emittance preservation and luminosity tuning techniques have been tested and developed in order to meet the challenging luminosity requirements.</p><p>Beam-based alignment was shown to be insufficient for reduction of emittance growth. Emittance tuning bumps provide an additional powerful preservation tool. After initial studies of tuning bumps designed to treat certain imperfections, a general strategy for design of optimised bumps was developed. The new bumps are optimal both in terms of emittance reduction performance and convergence speed. They were clearly faster than previous bumps and reduced emittance growth by nearly two orders of magnitude both for CLIC and ILC.</p><p>Time-dependent imperfections such as ground motion and magnet vibrations also limit the performance of the colliders. This type of imperfections was studied in detail, and a new feedback system for optimal reduction of emittance growth was developed and shown to be approximately ten times more efficient than standard trajectory feedbacks.</p><p>The emittance tuning bumps require fast and accurate diagnostics. The possibility of measuring emittance using a wide laserwire was introduced and simulated with promising results. While luminosity cannot be directly measured fast enough, it was shown that a beamstrahlung tuning signal could be used for efficient optimisation of a number of collision parameters using tuning bumps in the Final Focus System.</p><p>Complete simulations of CLIC emittance tuning bumps, including static and dynamic imperfections and realistic tuning and emittance measurement procedures, showed that an emittance growth six times lower than that required may be obtained using these methods.</p>
353

Estudo do desenvolvimento da escuta melódica de adultos integrados a coros vocacionais / Study about the processes of development of melodic hearing by adult choral amateur singers

Lopes, Paulo 27 October 2010 (has links)
O objetivo principal deste trabalho é estudar os processos de desenvolvimento da escuta melódica de adultos, sem formação musical, integrados a coros vocacionais, com o intuito de poder melhorar a performance vocal do grupo. Tendo como objeto o processo de formação do Coral Oficina Comunicantus, grupo integrado ao Comunicantus: Laboratório Coral do Departamento de Música da Escola de Comunicações e Artes da Universidade de São Paulo. Nosso método de coleta de dados foi baseado nas observações dos ensaios e nas análises das avaliações (relatórios) feitas pelos monitores integrados ao Comunicantus: Laboratório Coral, através dos quais procuramos vislumbrar as necessidades de aprendizagem dos coralistas do coro supracitado. Por se tratar de uma pesquisa ora de observação ora interativa, atuamos combinando tais ações e orientando o desenvolvimento das habilidades inerentes à escuta melódica em aspectos pré-definidos. Durante o processo investigativo, utilizamos como método referencial de análise, dos conteúdos musicais, os trabalhos do Prof. Dr. Marco Antonio da Silva Ramos e do Prof. Paulo Rubens Morais Costa e, por outro lado, a produção bibliográfica de educadores como César Coll e Teresa Mauri, que atuaram na reforma escolar espanhola, de forma a subsidiar nossas escolhas pedagógicas e didáticas para atuar junto aos coralistas. Como resultado desse processo, pudemos desenvolver algumas atividades que contribuíram para a resolução de certas necessidades de aprendizagem momentâneas deste grupo e também suscitaram a criação de outras que foram utilizadas oportunamente, após o término do prazo definido de observação e interação a que este trabalho se refere. / This dissertation aims mainly at studying the processes of development of melodic hearing by adults who do not have any musical formation and yet join vocational choirs in order to improve the vocal performance of the group. Its object is the process of formation of the Educational Lab-Choir Comunicantus, which belongs to the Comunicantus Choral Office of the Department of Music of the School of Communication and Arts of the University of São Paulo. The method of data collection was based on rehearsal observations and on the analysis of evaluations (reports) made by student trainees integrated in the Comunicantus Choir Office, through which we trie to identify the gaps in learning of the choir singers. As the research is partly made up of observations and partly interactive, action was taken so as to combine these actions and give advice on the development of skills innate to melodic hearing in predefined aspects. Along the process of investigation, the Referencial de Análises of the musical contents by Professor D. Marco Antonio da Silva Ramos and Professor Paulo Rubens Morais Costa were used as a method. On the other hand, the works by educators as César Coll and Teresa Mauri, who worked in the Spanish school reform, were used to provide pedagogical and didactic choices for us to act with the choral singers. As a result of this process, some activities were developed that contributed to offer solution to some specific learning needs of this group and also made possible the creation of others that were used, whenever suitable, after the period of observation and interaction.
354

On the understanding of organic thin film growth and the changes in structure formation induced by molecular chemical tuning

Zykov, Anton 24 February 2017 (has links)
Funktionale organische Moleküle bergen ein hohes Potential für den Einsatz in zukunftsprägenden Technologien wie organischen Leuchtdioden (OLED), Solarzellen, Transistoren und Bio-Sensoren. Eines der Herstellungsverfahren beruht auf der Gasphasenabscheidung der Moleküle, die auf dem Substrat mittels Selbstorganisation zu dünnen Schichten wachsen. Auf Grund der komplexen Wechselwirkungen und des Einflusses der Schichtmorphologie auf die Funktionalität der dünnen Schichten stellt der Wachstumsprozess sowohl für die anwendungsorientierte als auch für die Grundlagenforschung eine hochinteressante und wichtige wissenschaftliche Herausforderung dar, mit der sich die vorliegende Arbeit auseinandersetzt. Die experimentellen Resultate und Konzepte, die in dieser Arbeit vorgestellt werden, leisten neue Beiträge für das Verständnis von organischem Wachstum. Der demonstrierte Einfluss von chemischer Modifikation auf verschiedene Aspekte des Strukturwachstums, wie z.B. auf die Filmrauigkeit, Kristallphasenreinheit und molekulare Diffusivität, zeigt zudem das hohe Potential dieser Methode zur Steuerung des organischen Wachstums. Aus den genannten Gründen kann diese Arbeit neue Impulse für die Erforschung und spätere Anwendung von funktionalen organischen Dünnschichtsystemen setzen. / Functional organic molecules are promising for the application in future relevant technologies such as organic light emitting diodes (OLEDs), solar cells, transistors and bio-sensors. One of the processing methods to fabricate organic devices is organic molecular beam deposition. In this process, the complexly interacting molecules grow via self-assembly as thin films on a substrate. Due to the close structure-property relationship, the growth process constitutes a highly interesting and important scientific challenge for both application oriented as well as fundamental research and is the topic of the present thesis. The experimental results and conceptual methods presented in this thesis contribute new stimuli to the understanding of the molecular self-assembly. The demonstrated influence of chemical tuning on various facets of structure formation, such as film roughness, crystal phase purity and molecular diffusivities, uncovers the strong potential of this approach for steering organic growth. Therefore, the present work has implications for future research and application of functional organic thin films.
355

Estudo do desenvolvimento da escuta melódica de adultos integrados a coros vocacionais / Study about the processes of development of melodic hearing by adult choral amateur singers

Paulo Lopes 27 October 2010 (has links)
O objetivo principal deste trabalho é estudar os processos de desenvolvimento da escuta melódica de adultos, sem formação musical, integrados a coros vocacionais, com o intuito de poder melhorar a performance vocal do grupo. Tendo como objeto o processo de formação do Coral Oficina Comunicantus, grupo integrado ao Comunicantus: Laboratório Coral do Departamento de Música da Escola de Comunicações e Artes da Universidade de São Paulo. Nosso método de coleta de dados foi baseado nas observações dos ensaios e nas análises das avaliações (relatórios) feitas pelos monitores integrados ao Comunicantus: Laboratório Coral, através dos quais procuramos vislumbrar as necessidades de aprendizagem dos coralistas do coro supracitado. Por se tratar de uma pesquisa ora de observação ora interativa, atuamos combinando tais ações e orientando o desenvolvimento das habilidades inerentes à escuta melódica em aspectos pré-definidos. Durante o processo investigativo, utilizamos como método referencial de análise, dos conteúdos musicais, os trabalhos do Prof. Dr. Marco Antonio da Silva Ramos e do Prof. Paulo Rubens Morais Costa e, por outro lado, a produção bibliográfica de educadores como César Coll e Teresa Mauri, que atuaram na reforma escolar espanhola, de forma a subsidiar nossas escolhas pedagógicas e didáticas para atuar junto aos coralistas. Como resultado desse processo, pudemos desenvolver algumas atividades que contribuíram para a resolução de certas necessidades de aprendizagem momentâneas deste grupo e também suscitaram a criação de outras que foram utilizadas oportunamente, após o término do prazo definido de observação e interação a que este trabalho se refere. / This dissertation aims mainly at studying the processes of development of melodic hearing by adults who do not have any musical formation and yet join vocational choirs in order to improve the vocal performance of the group. Its object is the process of formation of the Educational Lab-Choir Comunicantus, which belongs to the Comunicantus Choral Office of the Department of Music of the School of Communication and Arts of the University of São Paulo. The method of data collection was based on rehearsal observations and on the analysis of evaluations (reports) made by student trainees integrated in the Comunicantus Choir Office, through which we trie to identify the gaps in learning of the choir singers. As the research is partly made up of observations and partly interactive, action was taken so as to combine these actions and give advice on the development of skills innate to melodic hearing in predefined aspects. Along the process of investigation, the Referencial de Análises of the musical contents by Professor D. Marco Antonio da Silva Ramos and Professor Paulo Rubens Morais Costa were used as a method. On the other hand, the works by educators as César Coll and Teresa Mauri, who worked in the Spanish school reform, were used to provide pedagogical and didactic choices for us to act with the choral singers. As a result of this process, some activities were developed that contributed to offer solution to some specific learning needs of this group and also made possible the creation of others that were used, whenever suitable, after the period of observation and interaction.
356

Educação superior e políticas inter-regionais: um estudo sobre o projeto Alfa Tuning América Latina nas universidades brasileiras / Higher education and interregional policies: a study on the Alfa Tuning Latin America project in Brazilian universities

Puziol, Jeinni Kelly Pereira 07 April 2017 (has links)
A presente tese discute a implementação do Projeto Alfa Tuning América Latina no Brasil, bem como se, e de que maneira, suas diretrizes foram incorporadas ao contexto da prática das universidades brasileiras participantes. O Projeto Alfa Tuning América Latina de acordo com os documentos oficiais, é uma proposta de afinação do ensino superior latino-americano e europeu, a partir de uma metodologia baseada na noção de competências e de uma rede de comunidades de aprendizagem. Desenvolvido em duas fases, a primeira, entre 2004 e 2007 e a segunda, entre 2011 e 2014, o Projeto Alfa Tuning América Latina integra as políticas de desenvolvimento e cooperação internacional da União Europeia e é financiado pela Comissão Europeia. Para análise do processo de implementação das diretrizes do Projeto Alfa Tuning América Latina nas universidades brasileiras participantes, considerando o cenário de governança multiescalar, os ajustes estruturais e espaço-temporais econômicos, políticos e sociais, foram estudados os relatórios oficiais do Projeto Alfa Tuning América Latina, realizadas entrevistas semiestruturadas com participantes da segunda fase do Projeto e analisados os projetos pedagógicos de seis cursos de graduação em universidades do Brasil. O referencial teórico da tese está pautado no ciclo de políticas e na análise das políticas interregionais de educação superior vinculadas ao entendimento da lógica global do modo de produção capitalista, sustentado-se, principalmente, nos seguintes autores: Bowe e Ball (1992), Ball (2012) e Harvey (2003; 2006; 2011; 2013). Este referencial permitiu compreender a relação do Projeto Alfa Tuning América Latina com seu contexto de influência (cenário de acumulação capitalista), contexto de elaboração da política (cenário da União Europeia) e contexto da prática (universidades brasileiras participantes). Desse modo, constatou-se que o Projeto Alfa Tuning América Latina é uma das ações de territorialização, desterritorialização e reterritorialização de políticas educacionais da União Europeia, que no cenário de governança multiescalar supera fronteiras nacionais para suprir as demandas do mercado global, em que a educação superior, pautada na competitividade, é vista como impulsionadora do desenvolvimento econômico. Verificou-se que o Projeto Alfa Tuning América Latina foi introduzido no Brasil fora dos marcos regulatórios do Estado, sendo acordado com universidades e docentes, desenvolvido a partir de redes políticas e não de decretos ou políticas públicas e que a implementação de suas diretrizes nas universidades brasileiras ocorreu de maneira pontual e discursiva. Entretanto, dada a complexidade das políticas inter-regionais que integram a dinâmica das regiões e das redes, os resultados do Projeto Alfa Tuning América Latina não podem ser dimensionados apenas pela implementação de suas diretrizes a curto prazo, mas também pelo seu potencial de influência nas políticas nacionais, pela adoção de conceitos, diagnósticos e metodologias e também pela possibilidade de legitimar outras políticas. / This thesis discusses the implementation of the Alfa Tuning Latin America Project in Brazil, as well as if and in what way its guidelines have been incorporated in the context of practice of the participating Brazilian universities. According to official documents, Alfa Tuning Latin America Project is a proposal to fine-tune both Latin American and European higher education, while having a methodology based on the notion of competencies and a network of learning communities as starting points. Alfa Tuning Latin America Project has been developed in two phases: the first one between 2004 and 2007, and the second between 2011 and 2014; it is part of the European Unions international cooperation and development policies and it is funded by the European Commission. In order to analyze the implementation process of Alfa Tuning Latin America Project guidelines within the participating Brazilian universities, while taking into account the multi-level governance scenario, as well as structural and spatio-temporal adjustments of social, political and economic order, Alfa Tuning Latin America Project official reports have been studied, semi-structured interviews have been conducted with participants in the second phase of the Project and the pedagogical projects of six undergraduate programs from Brazilian universities have been reviewed. The theoretical framework of this thesis is guided by the policy cycle approach as well as by the analysis of higher education interregional policies linked to the understanding of the global logic of capitalism, while mainly drawing on the following scholars: Bowe and Ball (1992), Ball (2012) and Harvey (2003; 2006; 2011; 2013). This framework has enabled the understanding of the relation between Alfa Tuning Latin America Project and its context of influence (scenario of capitalist accumulation), its context for the development of the policy (European Union scenario) and its context of practice (participating Brazilian universities). In this way, we found out that Alfa Tuning Latin America Project is one of the actions taken by the European Union for the territorialization, deterritorialization and reterritorialization of educational policies, which in the multi-level governance scenario overcomes national borders toward meeting the demands of the global market, where higher education, featured by competitiveness, is seen as a driver of economic development. We observed that Alfa Tuning Latin America Project has been introduced in Brazil regardless of States regulatory frameworks by being agreed among universities and academics, while being developed through political networks rather than decrees or public policies and also that the implementation of its guidelines in Brazilian universities has happened in a specific and discursive way. Given the complexity of the interregional policies comprised in the dynamics of regions and networks, however, the results of Alfa Tuning Latin America Project cannot be merely assessed by the short-term implementation of its guidelines, but also by its potential of influence on national policies through the adoption of concepts, diagnoses and methodologies, as well as through the possibility to legitimize other policies.
357

Emittance preservation and luminosity tuning in future linear colliders

Eliasson, Peder January 2008 (has links)
The future International Linear Collider (ILC) and Compact Linear Collider (CLIC) are intended for precision measurements of phenomena discovered at the Large Hadron Collider (LHC) and also for the discovery of new physics. In order to offer optimal conditions for such experiments, the new colliders must produce very-high-luminosity collisions at energies in the TeV regime. Emittance growth caused by imperfections in the main linacs is one of the factors limiting the luminosity of CLIC and ILC. In this thesis, various emittance preservation and luminosity tuning techniques have been tested and developed in order to meet the challenging luminosity requirements. Beam-based alignment was shown to be insufficient for reduction of emittance growth. Emittance tuning bumps provide an additional powerful preservation tool. After initial studies of tuning bumps designed to treat certain imperfections, a general strategy for design of optimised bumps was developed. The new bumps are optimal both in terms of emittance reduction performance and convergence speed. They were clearly faster than previous bumps and reduced emittance growth by nearly two orders of magnitude both for CLIC and ILC. Time-dependent imperfections such as ground motion and magnet vibrations also limit the performance of the colliders. This type of imperfections was studied in detail, and a new feedback system for optimal reduction of emittance growth was developed and shown to be approximately ten times more efficient than standard trajectory feedbacks. The emittance tuning bumps require fast and accurate diagnostics. The possibility of measuring emittance using a wide laserwire was introduced and simulated with promising results. While luminosity cannot be directly measured fast enough, it was shown that a beamstrahlung tuning signal could be used for efficient optimisation of a number of collision parameters using tuning bumps in the Final Focus System. Complete simulations of CLIC emittance tuning bumps, including static and dynamic imperfections and realistic tuning and emittance measurement procedures, showed that an emittance growth six times lower than that required may be obtained using these methods.
358

Educação superior e políticas inter-regionais: um estudo sobre o projeto Alfa Tuning América Latina nas universidades brasileiras / Higher education and interregional policies: a study on the Alfa Tuning Latin America project in Brazilian universities

Jeinni Kelly Pereira Puziol 07 April 2017 (has links)
A presente tese discute a implementação do Projeto Alfa Tuning América Latina no Brasil, bem como se, e de que maneira, suas diretrizes foram incorporadas ao contexto da prática das universidades brasileiras participantes. O Projeto Alfa Tuning América Latina de acordo com os documentos oficiais, é uma proposta de afinação do ensino superior latino-americano e europeu, a partir de uma metodologia baseada na noção de competências e de uma rede de comunidades de aprendizagem. Desenvolvido em duas fases, a primeira, entre 2004 e 2007 e a segunda, entre 2011 e 2014, o Projeto Alfa Tuning América Latina integra as políticas de desenvolvimento e cooperação internacional da União Europeia e é financiado pela Comissão Europeia. Para análise do processo de implementação das diretrizes do Projeto Alfa Tuning América Latina nas universidades brasileiras participantes, considerando o cenário de governança multiescalar, os ajustes estruturais e espaço-temporais econômicos, políticos e sociais, foram estudados os relatórios oficiais do Projeto Alfa Tuning América Latina, realizadas entrevistas semiestruturadas com participantes da segunda fase do Projeto e analisados os projetos pedagógicos de seis cursos de graduação em universidades do Brasil. O referencial teórico da tese está pautado no ciclo de políticas e na análise das políticas interregionais de educação superior vinculadas ao entendimento da lógica global do modo de produção capitalista, sustentado-se, principalmente, nos seguintes autores: Bowe e Ball (1992), Ball (2012) e Harvey (2003; 2006; 2011; 2013). Este referencial permitiu compreender a relação do Projeto Alfa Tuning América Latina com seu contexto de influência (cenário de acumulação capitalista), contexto de elaboração da política (cenário da União Europeia) e contexto da prática (universidades brasileiras participantes). Desse modo, constatou-se que o Projeto Alfa Tuning América Latina é uma das ações de territorialização, desterritorialização e reterritorialização de políticas educacionais da União Europeia, que no cenário de governança multiescalar supera fronteiras nacionais para suprir as demandas do mercado global, em que a educação superior, pautada na competitividade, é vista como impulsionadora do desenvolvimento econômico. Verificou-se que o Projeto Alfa Tuning América Latina foi introduzido no Brasil fora dos marcos regulatórios do Estado, sendo acordado com universidades e docentes, desenvolvido a partir de redes políticas e não de decretos ou políticas públicas e que a implementação de suas diretrizes nas universidades brasileiras ocorreu de maneira pontual e discursiva. Entretanto, dada a complexidade das políticas inter-regionais que integram a dinâmica das regiões e das redes, os resultados do Projeto Alfa Tuning América Latina não podem ser dimensionados apenas pela implementação de suas diretrizes a curto prazo, mas também pelo seu potencial de influência nas políticas nacionais, pela adoção de conceitos, diagnósticos e metodologias e também pela possibilidade de legitimar outras políticas. / This thesis discusses the implementation of the Alfa Tuning Latin America Project in Brazil, as well as if and in what way its guidelines have been incorporated in the context of practice of the participating Brazilian universities. According to official documents, Alfa Tuning Latin America Project is a proposal to fine-tune both Latin American and European higher education, while having a methodology based on the notion of competencies and a network of learning communities as starting points. Alfa Tuning Latin America Project has been developed in two phases: the first one between 2004 and 2007, and the second between 2011 and 2014; it is part of the European Unions international cooperation and development policies and it is funded by the European Commission. In order to analyze the implementation process of Alfa Tuning Latin America Project guidelines within the participating Brazilian universities, while taking into account the multi-level governance scenario, as well as structural and spatio-temporal adjustments of social, political and economic order, Alfa Tuning Latin America Project official reports have been studied, semi-structured interviews have been conducted with participants in the second phase of the Project and the pedagogical projects of six undergraduate programs from Brazilian universities have been reviewed. The theoretical framework of this thesis is guided by the policy cycle approach as well as by the analysis of higher education interregional policies linked to the understanding of the global logic of capitalism, while mainly drawing on the following scholars: Bowe and Ball (1992), Ball (2012) and Harvey (2003; 2006; 2011; 2013). This framework has enabled the understanding of the relation between Alfa Tuning Latin America Project and its context of influence (scenario of capitalist accumulation), its context for the development of the policy (European Union scenario) and its context of practice (participating Brazilian universities). In this way, we found out that Alfa Tuning Latin America Project is one of the actions taken by the European Union for the territorialization, deterritorialization and reterritorialization of educational policies, which in the multi-level governance scenario overcomes national borders toward meeting the demands of the global market, where higher education, featured by competitiveness, is seen as a driver of economic development. We observed that Alfa Tuning Latin America Project has been introduced in Brazil regardless of States regulatory frameworks by being agreed among universities and academics, while being developed through political networks rather than decrees or public policies and also that the implementation of its guidelines in Brazilian universities has happened in a specific and discursive way. Given the complexity of the interregional policies comprised in the dynamics of regions and networks, however, the results of Alfa Tuning Latin America Project cannot be merely assessed by the short-term implementation of its guidelines, but also by its potential of influence on national policies through the adoption of concepts, diagnoses and methodologies, as well as through the possibility to legitimize other policies.
359

Reconfigurable Microwave/Millimeter-Wave Filters: Automated tuning and Power Handling Analysis

Pintu Adhikari (11640121) 03 November 2021 (has links)
<div>In recent years, intelligent devices such as smartphones and self-driving cars are becoming ubiquitous in daily life, and thus, wireless communication is turning out to be increasingly omnipresent. To efficiently utilize the electromagnetic spectrum, automatically reconfigurable software-controlled radio transceivers are drawing an extensive amount of attention. In order to implement a reconfigurable radio transceiver, automatically tunable RF front-end components such as tunable filters are indispensable. Over the last decade, tunable filters have shown promising performance with high-quality factor (Q), a wide tuning range, and high-power handling. However, most of the existing tunable filters are manually adjusted. In this regard, this research work focuses on developing a novel automatic software-driven tuning technique for continuously tunable microwave and millimeter-wave filters.</div><div><br></div><div><br></div><div>First, a K-band continuously tunable bandpass filter has been demonstrated with contactless printed circuit board (PCB) tuners. Then, an automatic tuning technique based on deep-Q learning has been proposed and realized to tune a filter with contactless tuners automatically. Two-pole, three-pole, and four-pole bandpass filters are experimentally tested as examples without any human intervention to prove the feasibility of the tuning technique. For the first time, unlike a look-up table, the filters can be continuously tuned at a practically infinite number of frequencies inside the tuning range. </div><div><br></div><div>Next, a K/Ka-band tunable absorptive bandstop filter (ABSF) has been designed and fabricated in low-cost PCB technology. Contrary to a reflective bandstop filter, an ABSF filter is preferred for interference mitigation due to its deeper notch and lower reflection. However, the absorbed power may limit the filter's power handling. Therefore, lastly, a comparative analysis of power handling capability (PHC) between a reflective bandstop filter and an absorptive bandstop filter has been studied theoretically and experimentally in this dissertation.</div>
360

Systém automatického ladění pro sedmistrunné kytary / The automatic self tuning system for seven-string guitars

Jeřábek, Vojtěch January 2017 (has links)
The thesis describes a realization of the automatic self tuning system for sevenstring guitars. There are comparisons of commercial and uncommercial solutions for six-string guitars. There is also evaluation of useful parts for seven-string guitars. Thesis contains a description of a requirements for individual parts and a control software with respect on real guitar properties and used computing algorithm. In the second part of thesis, there is a description of final system design and its realisation including the control software. This is also related with testing of the entire system.

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