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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.
111

On the synchronization of two metronomes and their related dynamics

Carranza López, José Camilo [UNESP] 05 June 2017 (has links)
Submitted by CAMILO CARRANZA (carranzacamilo@gmail.com) on 2017-07-25T19:58:22Z No. of bitstreams: 1 Camilo_PhD_Thesis.pdf: 11035322 bytes, checksum: efe400c07b13cabff41e927078789c59 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-26T18:31:30Z (GMT) No. of bitstreams: 1 carranzalopez_jc_dr_ilha.pdf: 11035322 bytes, checksum: efe400c07b13cabff41e927078789c59 (MD5) / Made available in DSpace on 2017-07-26T18:31:30Z (GMT). No. of bitstreams: 1 carranzalopez_jc_dr_ilha.pdf: 11035322 bytes, checksum: efe400c07b13cabff41e927078789c59 (MD5) Previous issue date: 2017-06-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / 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 do que em anti-fase. Adicionalmente se encontrou que, para dado valor de amortecimento, diminuir a massa da base leva a uma situação em que a sincronização em anti-fase é mais comum do que a sincronização em fase. / This thesis concerns a theoretical and experimental investigation into the synchronization of two coupled metronomes. A simplified model is proposed to study in-phase and anti-phase synchronization of two metronomes oscillating on a mobile base. A description of the escapement mechanism driving metronomes is given and its relationship with the van der Pol oscillator is discussed. Also an experimental value for the damping in the metronome is determined. The instantaneous frequency of the responses from both numerical and experimental data is used in the analysis. Unlike previous studies, measurements are made using videos and the time domain responses of the metronomes extracted by means of tracker software. Basins of attraction are used to investigate the relationship between initial conditions, parameters and both final synchronization states. The relationship between the model and a previous pendulum model is also shown. The key parameters concerning both kind of synchronization have been found to be the mass ratio between the metronome mass and the base mass, and the damping in the system. It has been shown, both theoretically and experimentally, that the frequency of oscillation of the metronomes increases when the system reaches in-phase synchronization, and is the same as an isolated metronome when the system synchronizes in anti-phase. From numerical simulations, it has been found that, in general, increasing damping leads the system to synchronize more in-phase than in anti-phase. It has also been found that, for a given damping value, decreasing the mass of the base results in the situation where anti-phase synchronization is more common than in-phase synchronization.
112

Ensinando cinemática através da análise de movimentos em vídeos de captura de games

Silva Neto, Manoel Coelho da 21 August 2017 (has links)
Submitted by Larissa Vitoria Cardoso Cusielo (larissavitoria@id.uff.br) on 2017-05-22T15:59:28Z No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Manoel Coelho da Silva Neto - Dissertação Final.compressed.pdf: 2147671 bytes, checksum: c046094e9eb88ea2c91f4ebc1857ab0e (MD5) Manoel Coelho da Silva Neto - Produto Final.pdf: 4043748 bytes, checksum: ed0f262e5d26eb90ede963337eadcabc (MD5) / Rejected by Biblioteca do Aterrado BAVR (bavr@ndc.uff.br), reason: oi on 2017-05-22T16:23:42Z (GMT) / Submitted by Larissa Vitoria Cardoso Cusielo (larissavitoria@id.uff.br) on 2017-05-22T17:10:03Z No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Manoel Coelho da Silva Neto - Dissertação Final.compressed.pdf: 2147671 bytes, checksum: c046094e9eb88ea2c91f4ebc1857ab0e (MD5) Manoel Coelho da Silva Neto - Produto Final.pdf: 4043748 bytes, checksum: ed0f262e5d26eb90ede963337eadcabc (MD5) / Approved for entry into archive by Biblioteca do Aterrado BAVR (bavr@ndc.uff.br) on 2017-08-21T15:45:13Z (GMT) No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Manoel Coelho da Silva Neto - Dissertação Final.compressed.pdf: 2147671 bytes, checksum: c046094e9eb88ea2c91f4ebc1857ab0e (MD5) Manoel Coelho da Silva Neto - Produto Final.pdf: 4043748 bytes, checksum: ed0f262e5d26eb90ede963337eadcabc (MD5) / Made available in DSpace on 2017-08-21T15:45:13Z (GMT). No. of bitstreams: 3 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Manoel Coelho da Silva Neto - Dissertação Final.compressed.pdf: 2147671 bytes, checksum: c046094e9eb88ea2c91f4ebc1857ab0e (MD5) Manoel Coelho da Silva Neto - Produto Final.pdf: 4043748 bytes, checksum: ed0f262e5d26eb90ede963337eadcabc (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Ciências Exatas. Programa de Pós-Graduação em Ensino de Física. Volta Redonda,RJ. / Esta dissertação apresenta uma atividade de ensino centrada no aluno para tópicos de cinemática, utilizando Tecnologias de Informação e Comunicação (TICs) e o game Angry Birds como motivador do engajamento do aluno no processo de aprendizagem. Em nosso projeto, conduzido no Colégio Estadual Conde Pereira Carneiro, em Angra dos Reis, RJ, os alunos cumpriram atividades de recuperação escolar em aulas vagas do próprio turno de presença, onde, capturando uma sessão de jogo de Angry Birds em vídeo, posteriormente analisavam os movimentos nele contidos no software Tracker. Com isso, trabalharam-se todos os conceitos fundamentais da cinemática, como posição, deslocamento, velocidade e aceleração, além de tópicos da cinemática, como movimento uniforme, acelerado e de projéteis. Os resultados sugerem que este tipo de atividade é efetiva em promover uma maior aproximação do aluno à disciplina de Física, proporcionando engajamento e estimulando autonomia e independência no aprendizado do estudante, qualidades desejáveis em qualquer metodologia de ensino. / This work presents a student-centered teaching activity for teaching kinematics, using Communication and Information Tecnologies, and the game Angry Birds as the motivator for student engagement in the learning process. Our project, conducted at Colégio Estadual Conde Pereira Carneiro, in Angra dos Reis, RJ, consisted of sessions where students captured a playing session of Angry Birds in video, with later analysis of the motion of the birds through the software Tracker. They dealt, thus, with all the fundamental concepts of kinematics, such as position, displacement, velocity and acceleration, as well as with topics specific to kinematics, such as uniform and accelerated motion and projectile motion. The results suggest that this kind of activity promotes a greater closeness to the discipline of Physics, as well as engagement and independence in learning, something highly desirable in teaching and learning.
113

Look2Hook - A Comparative Study of Eye-tracker and Mouse Based Object Selection in a Complex Environment / Look2Hook - En Komparativ Studie av Eye-tracker och Musbaserad Objekt Selektion i en Komplex Miljö

Erlandsson, Oskar January 2021 (has links)
In this thesis the Tobii eye-tracker 4L was used to investigate how well eye-tracking solutions such as a confirmation-click and dwell-time algorithm compares to the standard mouse input device when performing selection tasks in a map environment. In order to distinguish the different complexity one could face, two user cases are proposed. Scenario one includes non clustered objects. Scenario two include clustered occluded objects. A user study with nine different participants where conducted in order to compare the execution times and find out how error prone the different methods were. Each test participant performed eight different tests, three in the non-clustered scenario and five in the clustered scenario. In two of the tests in the clustered scenario test participants were aided with zooming through a zoom algorithm. The methods was evaluated by calculating the average execution times and errors along with the corresponding standard deviations. In order to grasp the users experience a subjective cognitive load score was calculated with the help of a questionnaire. The eye-tracker methods was found to be competitive in comparison to mouse interaction in the more simple non-clustered case. However, in a more complex scenario such as the clustered case the mouse interaction had the lowest average completion time and cognitive load score. A different type of selection behaviour was discovered among the test participants in the clustered scenario due to the difference in precision between the eye-tracker and mouse interaction. Finally interesting areas to consider in the future is presented and discussed. / I denna avhandling användes en Tobii eye-tracker 4L för att undersöka hur väl eye-tracking metoder så som en bekräftelseklick och dwell-time algoritm jämför sig med standard mus interaktion vid objekt selektion i en kartmiljö. För att urskilja variationen i komplexitet man kan möta föreslås två olika användarfall. Scenario ett inkluderar objekt som är distinktivt separerade och därav ej grupperade. Scenario två inkluderar grupperade samt ockluderade objekt. En användarstudie med nio olika deltagare genomfördes för att jämföra exekveringstiderna och ta reda på hur felbenägna de olika metoderna var. Varje testdeltagare utförde åtta olika tester, tre i det icke-grupperade scenariot och fem i det grupperade scenariot. I två av testerna i det grupperade scenariot fick deltagarna hjälp med att zooma genom en zoomalgoritm. Metoderna utvärderades genom att beräkna de genomsnittliga exekveringstiderna samt antal fel tillsammans med motsvarande standardavvikelser. För att förstå hur användarna upplevde de olika metoderna togs en subjektiv kognitiv belastningspoäng fram genom ett frågeformulär. Eye-tracker metoderna var konkurrenskraftiga i jämförelse med musinteraktion i det enklare fallet där objekt ej var grupperade. I ett mer komplext scenario, såsom i det grupperade fallet, hade dock musinteraktionen den lägsta genomsnittliga exekveringstiden och kognitiva belastningspoängen. En annan typ av selektions beteende upptäcktes bland testdeltagarna i det grupperade scenariot på grund av skillnaden i precision mellan eye-trackern och musinteraktionen. Slutligen presenteras och diskuteras intressanta områden att överväga vid framtida arbeten.
114

Tracking Under Countermeasures Using Infrared Imagery

Modorato, Sara January 2022 (has links)
Object tracking can be done in numerous ways, where the goal is to track a target through all frames in a sequence. The ground truth bounding box is used to initialize the object tracking algorithm. Object tracking can be carried out on infrared imagery suitable for military applications to execute tracking even without illumination. Objects, such as aircraft, can deploy countermeasures to impede tracking. The countermeasures most often mainly impact one wavelength band. Therefore, using two different wavelength bands for object tracking can counteract the impact of the countermeasures. The dataset was created from simulations. The countermeasures applied to the dataset are flares and Directional Infrared Countermeasures (DIRCMs). Different object tracking algorithms exist, and many are based on discriminative correlation filters (DCF). The thesis investigated the DCF-based trackers STRCF and ECO on the created dataset. The STRCF and the ECO trackers were analyzed using one and two wavelength bands. The following features were investigated for both trackers: grayscale, Histogram of Oriented Gradients (HOG), and pre-trained deep features. The results indicated that the STRCF and the ECO trackers using two wavelength bands instead of one improved performance on sequences with countermeasures. The use of HOG, deep features, or a combination of both improved the performance of the STRCF tracker using two wavelength bands. Likewise, the performance of the ECO tracker using two wavelength bands was improved by the use of deep features. However, the negative aspect of using two wavelength bands and introducing more features is that it resulted in a lower frame rate.
115

A study for the development of a laser tracking system utilizing multilateration for high accuracy dimensional metrology

Greeff, Gabriel Pieter 03 1900 (has links)
MScEng / Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Accurate dimensional measurement devices are critical for international industrial competitiveness for South Africa. An overview of all the necessary components of a laser tracking system using a multilateration technique for very accurate dimensional metrology is presented. A prototype laser tracker station was built to further investigate this type of system. The prototype successfully tracks a target within a volume of at least 200 200 200 mm3, approximately 300 mm away from the tracker. This system includes the mechanical design of a prototype tracker station, electronic implementation of ampli cation and motor control circuits, a tracking control algorithm, microcontroller programming and interfacing, as well as a user interface. Kinematic modelling along with Monte Carlo analyses nd the main error source of such a tracker as the beam steering mechanism gimbal axes misalignment. Multilateration is also motivated by the results found by the analysis. Furthermore, an initial sequential multilateration algorithm is developed and tested. The results of these tests are promising and motivate the use of multilateration over a single beam laser tracking system. / AFRIKAANSE OPSOMMING: Dit is van kritieke belang dat Suid-Afrika akkurate dimensionele metingstoestelle ontwikkel vir internasionale industriële medinging. 'n Oorsig van al die nodige komponente vir 'n Laser-Volgsisteem, wat slegs van multilaterasie gebruik maak om baie akkurate drie dimensionele metings te kan neem, word in hierdie projek voorgestel. 'n Prototipe Laser-Volgsisteem-stasie word gebou om so 'n sisteem verder te ondersoek. Die prototipe slaag wel daarin om 'n teiken, binne 'n volume van 200 200 200 mm3 op 'n afstand van omtrent 300 mm te volg. Die sisteem sluit die meganiese ontwerp van die sodanige stasie, elektroniese seinversterking, motorbeheer, 'n volgingsbeheer algoritme, mikroverwerker programeering en intergrasie, asook 'n gebruikerskoppelvlak program in. Kinematiese modelering, tesame met Monte Carlo simulasies, toon aan dat die hoof oorsaak van metingsfoute by so 'n stasie by die rotasie-asse van die laserstraal-stuurmeganisme, wat nie haaks is nie, lê. Die multilaterasie metode word ook verder ondersteun deur dié modelering. 'n Algoritme wat sekwensiële multilateratsie toepas word boonop ontwikkel en getoets. Die resultate van die toetse dui daarop dat die algoritme funksioneer en dat daar voordele daarin kan wees om so 'n metode in plaas van 'n Enkelstraal-Volgsisteem te gebruik.
116

OPTICAL SLIP-RING CONNECTOR

Xu, Guoda, Bartha, John M., McNamee, Stuart, Rheaume, Larry, Khosrowabadi, Allen 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Current ground-based tracking systems at the DoD test and training ranges require transmission of a variety of signals from rotating platform to fixed control and process center. Implementation of commercial off the shelf (COTS) solution for transmitting high-speed, multiple-channel data signals over a rotational platform prompt the development of an advanced electro-optic hybrid rotating-to-fixed information transmission technology. Based on current demand, an Air Force-sponsored Small Business Innovative Research (SBIR) contract has been awarded to Physical Optics Corporation (POC) to modify existing tracking mounts with a unique electro-optic hybrid rotary joint (EOHRJ). The EOHRJ under current development is expected to provide the following features: 1) include a specially designed electrical slip-ring, which is able to accommodate hundreds of transmission channels, including electrical power, control, feedback, and low-speed data signals; 2) include an optical fiber slip-ring which, by incorporating with electrical time division mulitplexing (TDM) and optical wavelength division multiplexing (WDM) technologies, is able to provide multiple channel, high data rate (over gigabits per second), and bi-directional signal transmission; and 3) is designed to be reliable for harsh environmental operation, adaptive to stringent size requirement, and accommodating to existing electrical and mechanical interfaces. Besides the military use, other possible commercial applications include on board monitoring of satellite spinners, surveillance systems, instrumentation and multi spectral vision systems, emergency/medical instruments, remote sensing, and robotics.
117

Detector Development for the High Luminosity Large Hadron Collider

Rieger, Julia 02 August 2016 (has links)
Um das Entdeckungspotential des Large Hadron Colliders auszunutzen, wird er beginnend 2024 zum High Luminosity Large Hadron Collider ausgebaut. Neue Detektorherausforderungen entstehen durch die höhere instantane Luminosität und den höheren Teilchenfluss. Der neue ATLAS Inner Tracker wird den aktuellen Spurdetektor ersetzen, um mit diesen Herausforderungen umzugehen. Es gibt viele Pixeldetektortechnologien zur Teilchenspurerkennung, jedoch muss ihre Eignung für den ATLAS Inner Tracker untersucht werden. Aktive Hochspannungs-CMOS-Sensoren, die in industriellen Prozessen produziert werden, bieten eine schnelle Auslese und Strahlenhärte. In dieser Arbeit wird der HV2FEI4v2-Sensor, der kapazitiv mit dem ATLAS-FE-I4-Auslesechip gekoppelt ist, dahingehend charakterisiert, ob er für eine Verwendung in einer der äußeren Lagen des ATLAS Inner Tracker geeignet ist. Schlüsselgrößen des Prototypens, wie die Treffereffizienz und die Subpixelentschlüsselung, werden untersucht. Der frühe HV2FEI4v2-Prototyp zeigt vielversprechende Ergebnisse, die als Ausgangspunkt für weitere Entwicklungen dienen. Aktive CMOS-Sensoren stellen einen möglichen Kandidaten für einen kosteneffizienten Detektor für den High Luminosity Large Hadron Collider.
118

Odpověď zrakového analyzátoru při řízení vozidla v reálných podmínkách a na simulátoru při paralelní motorické úloze. / The response of the visual system when driving a car in real conditions and in a simulator during a parallel motor task.

Čiháková, Lucie January 2011 (has links)
Work title: The response of the visual system when driving a car in real conditions and in a simulator during a parallel motor task. Aims: To implement a laboratory measurement in a driving simulator and in real conditions during a parallel motor task. To track the response of the visual system during the task and to determine potential differences in the response of the visual system and in the speed in the simulator and in the real car environment. Methods: The laboratory measurement was realized in a driving simulator OCTAVIA II. The measurement in real conditions was realized in Škoda Octavia as well. The eye-tracking method was used to track the drivers` eyes. Results: In the simulator the more experienced driver managed to do the parallel motor task within a shorter period of time than the less experienced driver, lower frequency of looks at the radio during the tasks with the more experienced driver was not proved. There was not an evidence of more balanced speed during the drive with the more experienced driver in the simulator. On the average the driver spent shorter time doing the tasks in the real environment than in the simulator and the total number of looks at the radio was lower. The speed of the drive in the real environment was lower than the speed in the simulator. Key words:...
119

Investigação experimental do Kindchenschema lorenziano: Preferência visual de portadores de Síndrome de Williams e Transtorno do Espectro Autista em resposta a imagens neotênicas faciais / Experimental investigation of the lorenzian Kindchenschema: visual preference of Williams Syndrome patients and Autistic Spectrum Disorder in response to neotenic facial images

Carvalho, André Paulo Correa de 11 December 2018 (has links)
A neotenia é um importante processo biológico-evolutivo que conserva traços fenotípicos do jovem no indivíduo adulto. A neotenia modifica a velocidade típica da ontogênese das características morfológicas compartilhadas pelos ancestrais. Essas mudanças podem representar oportunidades de mudanças fenotípicas dramáticas com poucas alterações genéticas, possibilitando alterações de estados especializados. O etólogo Konrad Lorenz reconheceu características neotênicas em humanos e algumas espécies de mamíferos na fórmula estrutural do corpo (principalmente da face) típica de infantes. Essa fórmula corpórea foi batizada por Lorenz de Kindchenschema. Os humanos típicos respondem quando observam traços infantis ativando uma resposta chamada de Efeito Kindchenschema (EK). Neste efeito verifica-se uma diminuição da agressividade, estimulação do cuidado parental e engajamento social. São raros os trabalhos de escaneamento do olhar em portadores de disfunções do neurodesenvolvimento, como a Síndrome de Williams (SW) e o Transtorno do Espectro Autista (TEA). O presente trabalho é o primeiro na literatura a investigar o escaneamento do olhar em portadores de SW e TEA usando estímulos faciais neotênicos de humanos e animais. Na presente investigação foram estudados 21 portadores de SW e 25 portadores de TEA, o grupo controle (GC) contou com 33 participantes. Encontramos uma correspondência entre os resultados declarados do estímulo preferido e o tempo de fixação. Os resultados mostraram que todos os participantes fixaram mais a região dos olhos de humanos e animais, sendo que o GC fixou mais tempo do que os portadores de SW e TEA. Foi possível separar usando o tempo de fixação nos olhos e HeatMaps os três grupos investigados. É viável a produção de um exame clínico auxiliar rápido e não-invasivo para indivíduos com suspeita de uma disfunção do neurodesenvolvimento. Talvez a região do nariz e boca sejam menos importantes e as orelhas mais importantes do que pensávamos nos estímulos neotênicos. Os estímulos mais neotênicos de infantes humanos e animais produziram um padrão semelhantes do tempo de fixação nos três grupos estudados. Esses resultados demonstram que portadores de SW e TEA respondem positivamente a estímulos faciais neotênicos. Sugerimos que as novas investigações na área incorporem também como variáveis faciais as orelhas, cor do cabelo e olhos, e simetria facial / Neoteny is an important biological-evolutionary process that retains phenotypic traits of the young in the adult individual of a species. Neoteny modifies the typical ontogeny velocity of the morphological characteristics shared with the ancestors. These changes may represent opportunities for dramatic phenotype modifications with few genetic changes, allowing for alterations in specialized states. The ethologist Konrad Lorenz has recognized neotenic characteristics in humans and some species of mammals in the structural formula of the body (mainly of the face) typical of infants. This body formula was named by Lorenz Kindchenschema. Typical humans respond when they observe infant traits by activating a response called the Kindchenschema Effect (KE). In this effect, there is a decrease in aggressiveness, stimulation of parental care and social engagement. There is a paucity of eye scanning in individuals with neurodevelopmental disorders such as Williams Syndrome (WS) and Autistic Spectrum Disorder (ASD). The present work is the first in the literature to investigate the eye scanning in WS and ASD patients using neotenic facial stimuli of humans and animals. In the present investigation, 21 WS and 25 ASD participants were studied. The control group (CG) had 33 participants. We found a correspondence between the stated results of the preferred stimulus and the fixation time. The results showed that all the participants fixed more the region of the eyes of humans and animals, and the CG fixed more time than the WS and ASD participants. It was possible to distinguish, using the fixation time in the eyes and Heat Maps, the three groups. The production of a rapid and non-invasive auxiliary clinical examination is feasible for individuals suspected in presenting a neurodevelopmental dysfunction. Perhaps the nose and mouth areas are less important, and the ears are more important than previously considered with respect. The more neotenic stimuli of human and animal infants produced a similar pattern of fixation time in the three groups studied. This may represent a greater adaptive value than we thought of those with WS and ASD. We suggest that the new investigations can also incorporate facial variables as ears, hair color and eyes, and facial symmetry
120

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 irrigation

Gráh, Vanessa de Fátima 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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