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On the synchronization of two metronomes and their related dynamics /Carranza López, José Camilo. January 2017 (has links)
Orientador: Michael John Brennan / Resumo: Nesta tese são investigadas, teórica e experimentalmente, a sincronização em fase e a sincronização em anti-fase de dois metrônomos oscilando sobre uma base móvel, a partir de um modelo aqui proposto. Uma descrição do funcionamento do mecanismo de escapamento dos metrônomos é feita, junto a um estudo da relação entre este e o oscilador de van der Pol. Também uma aproximação experimental do valor do amortecimento do metrônomo é fornecida. A frequência instantânea das respostas, numérica e experimental, do sistema é usada na analise. A diferença de outros trabalhos prévios, os dados experimentais têm sido adquiridos usando vídeos dos experimentos e extraídos com ajuda do software Tracker. Para investigar a relação entre as condições iniciais do sistema e seu estado final de sincronização, foram usados mapas bidimensionais chamados ‘basins of attraction’. A relação entre o modelo proposto e um modelo prévio também é mostrada. Encontrou-se que os parâmetros relevantes em relação a ambos os tipos de sincronização são a razão entre a massa do metrônomo e a massa da base, e o amortecimento do sistema. Tem-se encontrado, tanto experimental quanto teoricamente, que a frequência de oscilação dos metrônomos aumenta quando o sistema sincroniza-se em fase, e se mantém a mesma de um metrônomo isolado quando o sistema sincroniza-se em anti-fase. A partir de simulações numéricas encontrou-se que, em geral, incrementos no amortecimento do sistema levam ao sistema se sincronizar mais em fase d... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
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Desenvolvimento de um rastreador solar biaxial / Development of a two-axis solar trackerCarvalho, Daniel Rizzo 11 July 2011 (has links)
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Previous issue date: 2011-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents the results of the study related to the production of electricity using a photovoltaic panel attached to the solar tracking mechanism. The objective was to develop a tracker equipment effective, with low cost and energy consumption, targeting the residential use, industrial and distributed generation of energy. Was evaluated the performance of the tracker, comparing it to a fixed system, showing its greatest potential for conversion. Based on the results analyzed, was observed a significant increase in energy conversion panel coupled to the tracking system in relation to fixed panel in a tilt angle accordingly local latitude. Its electromechanical performance was satisfactory, with no need for maintenance during the trial period and exposed to various weather conditions. The system has shown great potential for
application usability and robustness / Neste trabalho estão apresentados os resultados do estudo relacionado à
produção de eletricidade utilizando um painel fotovoltaico acoplado ao mecanismo de rastreamento solar. Objetivou-se desenvolver um equipamento eficaz no rastreamento, de baixo custo e consumo de energia, visando à possibilidade de uso residencial, industrial e a geração distribuída de energia. Avaliou-se o desempenho do rastreador, comparando-o com um sistema fixo. Com base nos resultados analisados, observou-se aumento significativo na produção de energia do painel fotovoltaico acoplado ao sistema de rastreamento em relação ao sistema fixo à inclinação da latitude local. Seu desempenho eletromecânico foi satisfatório, não necessitando de manutenção durante a fase experimental mesmo quando exposto às mais variadas condições de tempo. O sistema demonstrou grande potencial de aplicação, usabilidade e robustez.
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Desenvolvimento de um rastreador solar do tipo polar com ajuste do ?ngulo de inclina??oLira, Jos? R?mulo Vieira 23 January 2014 (has links)
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Previous issue date: 2014-01-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The use of solar energy for electricity generation has shown a growing
interest in recent years. Generally, the conversion of solar energy into electricity is made
by PV modules installed on fixed structures, with slope determined by the latitude of
the installation site. In this sense, the use of mobile structures with solar tracking, has
enabled increased production of the generated energy. However, the performance of these
structures depends on the type of tracker and the position control used. In this work, it is
proposed position control a strategy applied for a solar tracker, which will be installed in
Laboratory of Power Electronics and Renewable Energy (LEPER), located in the Federal
University of Rio Grande do Norte (UFRN). The tracker system is of polar type with daily
positioning east-west and tilt angle manual adjustment in the seasonal periods, from north
to south / O aproveitamento da energia solar para gera??o de energia el?trica tem apresentado
um crescente interesse nos ?ltimos anos. Geralmente nestes sistemas, a convers?o de
energia solar em el?trica ? realizada por m?dulos fotovoltaicos, instalados em estruturas
fixas, com inclina??o determinada em fun??o da latitude do local de instala??o. Neste
sentido, o uso de estruturas m?veis, com rastreamento solar, tem possibilitado o incremento
da produ??o da energia gerada. Por?m, o desempenho dessas estruturas depende
do tipo de rastreador instalado e do tipo de controle de posi??o utilizado. Nesta disserta??o,
? empregada uma estrat?gia de controle de posi??o aplicada a um rastreador solar,
que ser? instalado no Laborat?rio de Eletr?nica de Pot?ncia e Energias Renov?veis (LEPER),
localizado na Universidade Federal do Rio Grande do Norte (UFRN). O rastreador
ser? do tipo polar, com rastreamento di?rio no sentido leste-oeste e ajuste do ?ngulo de
inclina??o manual nos per?odos sazonais, no sentido norte-sul
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Avaliação do posicionamento de geradores fotovoltaicos com sistema rastreador manual aplicado ao bombeamento de água para irrigação / Evaluation of the position of photovoltaic generators with manual tracking system applied to water pumping for irrigationVanessa de Fátima Gráh 15 December 2014 (has links)
A matriz energética brasileira atualmente está concentrada na geração de energia hidrelétrica. Mas, devido aos últimos acontecimentos de escassez de recursos hídricos, faz-se necessário diversificar a matriz energética por meio do investimento em energias alternativas. O Brasil ainda possui muitas pessoas na área rural sem abastecimento de energia elétrica, fato que limita a implantação de técnicas agrícolas como a irrigação. Nesse contexto, a energia solar fotovoltaica (FV) é uma alternativa para diversificar a matriz energética brasileira e ampliar o uso de sistemas de irrigação. Foram instalados dois módulos FV, um estático e outro com um sistema de rastreamento solar manual de três passos, na área experimental do Departamento de Engenharia de Biossistemas - ESALQ/USP (22° 42\' 30\'\'S, 47° 38\' 00\'\'W, altitude de 546 metros). Para cada módulo FV, estático e móvel, foram acoplados sistemas de bombeamento de água para um sistema simulado de irrigação. O objetivo foi avaliar o incremento de energia FV gerada, tempo de bombeamento, volume bombeado e área irrigada; com o uso do sistema rastreador. A partir dos dados encontrados, verificou-se que o sistema rastreador solar manual de três passos apresentou maior eficiência na captação de energia (8 - 19% dia-1), quando comparado com geradores fixos; o que refletiu no incremento significativo do tempo de bombeamento (40 - 160 min dia-1), no volume bombeado (884 - 3479 litros dia-1) e na área irrigada (196 - 773 m² dia-1 para uma lâmina de irrigação de 4,5 mm). Com isso, o rastreador se mostrou uma alternativa técnica viável para melhorar a captação de energia solar e aumentar a área irrigada com um mesmo tamanho de área de gerador FV. Em relação ao investimento, o sistema rastreador custou apenas 0,2% do custo total da instalação FV, e proporcionou a redução do tempo de retorno do investimento em 2 anos e 5 meses comparado ao módulo FV estático. / The current Brazilian Energetic Matrix is concentrated in the generation of hydroelectric energy. But, due the latest water resources scarcity, it is necessary to diversify the energetic matrix by investing in alternatives energies. Brazil still have a plenty of people living in rural areas without supply of electric energy, this fact limits the implantation of agriculture techniques like irrigation. In this sense, the photovoltaic solar energy (PV) is an alternative to diversify the Brazilian Energetic Matrix and expand the use of irrigation systems. It were installed two PV modules, one static and another with solar three steps manual tracking system, Biosystems Engineering Department - ESALQ/USP (22° 42\' 30\'\'S, 47°38\' 00\'\'W, at 546 meters altitude). For each PV module, static and moving, it was coupled water pumping systems for simulated irrigation systems. The goal was evaluate the gain of the PV energy generated; pumping time; pumping volume and irrigated area; using the tracking system. From obtained data, it was observed that the solar three steps manual tracking system shows more efficiency in the energy harvesting (8 - 19% day-1), compared to static generator; which resulted in significant gain of pumping time (40 - 160 min day-1), pumping volume (884 - 3479 liters day-1) and irrigates area (196 - 773 m² day-1 for a irrigation depth equal 4.5 mm). Therewith, the tracking system shows a viable alternative technique to improve solar energy harvesting and increase the irrigated area with same area of PV generator. In relation to investment of the tracking system, it cost only 0.2 % of the total cost of PV installation and provided the reduction in the return on investment time of 2 years and 5 month compared to static PV module.
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Development and evaluation of a 6DOF interface to be used in a medical application / Utveckling och utvärdering av ett 6DOF gränssnitt för användning i en medicinsk tillämpningLarsson, Ulrica, Pettersson, Johanna January 2002 (has links)
This thesis was performed at the research centre CINECA in Bologna, Italy. An interface with six degrees of freedom, 6DOF, to be used in a virtual environ- ment for the positioning of medical components was developed in co-operation with IOR, one of the most important orthopaedic hospitals in Italy. The main reason for doing this was to find out whether or not a virtual en-viron-ment and 6DOF interaction could make the pre-operative planning of an ope-ration more efficient compared to other techniques. Is it easy to posi-tion an object using stereovision and a 6DOF tracker tool? Further-more, the interface might also be used in other applications and areas in the future. Described is the development of an interaction class especially constructed for the use of a tracking tool called a stylus pen. This tool takes advantage of all 6DOF, i.e. it recognises movements in the x, y and z directions and likewise the orientation of the tool around the three axis. Moreover, an application which uses the interaction class was created in order to evaluate its usefulness. The application enables the user to load, save and position objects within a virtual environment. The result of this evaluation is then described and discussed. In the evaluations it was shown that the stylus pen with 6DOF is an intuitive in-ter-action tool which works well for positioning. The stereovision also seems to further improve the users ability to position objects. However, the created interaction class needs to be further developed before itcan be implemented in a pre-operative planning tool.
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A feature based face tracker using extended Kalman filteringIngemars, Nils January 2007 (has links)
A face tracker is exactly what it sounds like. It tracks a face in a video sequence. Depending on the complexity of the tracker, it could track the face as a rigid object or as a complete deformable face model with face expressions. This report is based on the work of a real time feature based face tracker. Feature based means that you track certain features in the face, like points with special characteristics. It might be a mouth or eye corner, but theoretically it could be any point. For this tracker, the latter is of interest. Its task is to extract global parameters, i.e. rotation and translation, as well as dynamic facial parameters (expressions) for each frame. It tracks feature points using motion between frames and a textured face model (Candide). It then uses an extended Kalman filter to estimate the parameters from the tracked feature points.
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Gaze control for detail and overview in image exploration / Gaze control for detail and overview in image explorationRauhala, Sebastian January 2015 (has links)
Eye tracking technology has made it possible to accurately and consistently track a users gaze position on a screen. The human eyes center of focus, where it can see the most detailed information, is quite small at a given moment. The peripheral vision of humans have a much lower level of details than the center of gaze. Knowing this, it is possible to display a view that increases the level of resolution at the position of the users gaze point on the screen, while the rest of the screen keeps a lower resolution. An implementation of such a system can generate a representation of data with both detail and overview. The results indicate that even with simple gaze data processing it is possible to use gaze control to help explore details of a high resolution image. Gaze data processing often involve a compromise between stability, responsiveness and latency. A low latency, highly responsive gaze data filter would increase the risk for lens oscillation, and demand a higher concentration level from the viewer then a slower filter would. Applying a gaze data filter that allowed for smooth and stable lens movement for small saccades and responsive movements for large saccades proved successfully. With the uses of gaze control the user might be able to use a gaze aware application more efficient since gaze precedes actions. Gaze control would also reduce the need for hand motions which could provide a improved work environment for people interacting with computer.
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Arduinobaserad hundpejlLarsson, Oskar January 2017 (has links)
En hundpejl är idag något absolut nödvändigt vid löshundsjakt. Anledningen är att jägaren måste veta vart hunden är och helst också vad som sker. Idag när trafiken ökar allt mer är det av vikt att i tid kunna avgöra om hunden är på väg mot en trafikerad väg. Om hunden blir still har man möjlighet att i tid avgöra om den fastnat eller har gått i vatten och har möjlighet att hinna fram i tid för att hjälpa. Och då hundpejlar ofta kostar mer än 2000 kronor så finns det ett önskemål om att ta fram billigare varianter av hundpejlar. Målet i detta projekt är därför att konstruera, montera och programmera en pejl av Arduino UNO och Adafruit FONA 808 som uppfyller de krav, såsom en batteritid på minst 8 timmar och ett precisionsfel på max 5 meter, som en jägare ställer på en pejl som samtidigt är billigare en kommersiell produkt med liknande prestanda. Tillgångavägssättet var sådant att först studerades relevant litteratur såsom Adafruits produktbeskrivning och testkod, sedan testades de olika enskilt funktionerna, skicka, ta bort och läsa SMS samt hämta GPS-koordinater. När det var klart att funktionerna fungerade programmerades en kod som erhåller de egenskaper som en användare önskar sig. Därefter utvärderades pejlen för att se om den uppfyller de ställda kraven. Det som testades var pejlens vikt, batteritid och positionsnoggrannhet. Vikten mättes på en köksvåg, batteritiden mättes genom att testa batteriladdningen en gång i timmen över tre timmar och positionsnoggrannheten mättes på sådant sätt att pejlens koordinater jämfördes med resultatet från Google Maps och Eniro. Det visade sig att pejlen inte helt uppfyller alla krav, då positionsnoggrannheten inte direkt uppfyller de kraven som är ställda. Dock är enheten fortfarande användningsbar för spårning då den ger en tillräcklig generell area för att kunna hitta en hund på. Pejlen kan även användas i andra syften, till exempel placera den i en bil utifall stöld. Den ger även en bas att vidareutveckla en hundpejl ifrån till exempel skicka ljud till en telefon vilket även intresserar jägare. / A dog tracker is something that is essential when hunting with a dog. The reason is because the hunter needs to know where the dog is always, while preferably as well knowing what happens with the dog. Today, when the traffic is increasing and more, it is of importance to be able to determine whether the dog is heading for a busy road. The tracker also gives the hunter the possibility to rescue the dog if it gets stuck or fall in water. Dog trackers are of importance to the hunter, but they are also expensive, most costs more than 2000 SEK/230 USD, so there is a desire for a cheaper dog tracker that still fulfil the demands that hunters or dog owners require. The goal of this project is to design, build and program a dog tracker from Arduino UNO and Adafruit FONA 808, that meets the requirements stated by a user and at the same time are cheaper than the commercial equivalents. The method used are such that first relevant documents, such as Adafruit product description and testcode, are studied to gain an understanding of the units used. The units were then tested by the testcode to ensure that all parts are working correctly, this was done by testing read, delete and send SMS and get GPS-coordinates. When it was sure that all parts worked correctly a code was programmed that fulfilled all the requirements requested by a user. Then the finished dog tracker was evaluated to ensure that it fulfilled the requirements. Weight, battery time and positioning accuracy was tested, where weight was tested by a kitchen scale, battery time was tested by measuring the loss of charge once an hour over a period of three hours. From what was measured in those three hours a battery time was calculated by extrapolating loss of battery power/hour. The positioning accuracy was measured by using the dog trackers coordinates and comparing them to Google Maps and Eniro coordinates. The conclusion of the project is that the dog tracker didn’t fulfil all the requirements, its positioning accuracy didn’t reach the requirement of max 5-meter error. Though the dog tracker is still usable for tracking because it still gives a good enough positioning for finding a dog. The dog tracker can also be used for other purposes such as placing in a car to track it in event of a theft. The dog tracker also acts as a base for future developments, like using it to send sound which is also of interest for a hunter.
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Využití IT při analýze působení outdoorové reklamy / The application of IT for analysis of outdoor advertising effectsJeníčková, Tereza January 2009 (has links)
This thesis deals with use of Information technology for analysis of exposure to advertising communications, focusing on outdoor advertising.In the theoretical part is a brief outline of the beginnings and development of advertising, its effects on people, whether it can change their consumption behaviour, its position in the modern world and the way new technology along with psychology can be used for its analysis. The second part gives insight in the practical research of effects of outdoor advertising on people. There is an approach of Eye Camera technology in praxis, preparation for research, problems solved in its course. Data obtained are both verbally and graphically interpreted.
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Proposta de implementação de seguidor solar considerando condições nubladasBellini, Douglas January 2017 (has links)
Orientadora: Profa. Dra. Ahda Pionkoski Grilo Pavani / Coorientador: Prof. Dr. Ricardo da Silva Benedito / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, Santo André, 2017.
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