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Dissertations / Theses on the topic 'RGB LED'
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Coufal, Miroslav. "Modulární RGB LED displej." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220135.
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The aim of this master’s thesis was the design RGB LED display with Ethernet interface. I created a display module, controlled by a microcontroller ATmega 2560-16AU. These modules can be connected via a serial RS485 standard. Ethernet connection is made via plug-in interface that uses the programmable module Rabbit RCM 3200. I documented a proposal. I tested designed device.
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Zemánek, Petr. "Modulární RGB LED displej s rozhraním Ethernet." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220700.
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This thesis deals with an electronic circuit and a PCB of a modular RGB LED display with the Ehernet interface. Firstly, author describes a RGB colour model, features of RGB LED displays, ways of control them. The next chapter contains a short description of the Ethernet interface, UDP and TCP protocols and a lwIP TCP/IP stack. The last theoretical chapter is an introduction to ARM Cortex-M3 and Cortex-M4 based microcontrollers. The next chaper is deals with a hardware design of the modular RGB LED display. The device is designed to be modular. Individual devices can be combosed together and create a larger display. Data from the Ethernet interface will be displayed on the RGB LED matrix, resolution of the matrix is 32 × 32 (1024 diodes). A refresh frequency is 100 Hz, a color depth is High color (16 bits) and a scanning 1/16 (two rows is driven at the same time). The next chapter describes the firmware for the RGB LED display, all its logical parts including a web page. Author also created the PC application, which sends pictures using UDP protocol to individual modules.
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Biba, Panagiota. "New waviness measurement system using RGB LED lights." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-28314.
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Due to the rapid technological developments in the car industry and the high quality demands of customers, manufacturers and researchers focus on the reduction of surface roughness making use of various surface topography measurement systems. This master thesis focuses on development of a waviness measurement system (WMS) at Volvo Cars where light from different heights and angles illuminates the surface of an extended object in order to acquire images with different intensities due to shadowing effect and reflection. With this, surface irregularities and imperfections can be detected both in polished and unpolished surfaces for improving the car panels in the manufacturing process. The initial WMS idea was to illuminate the surface at different heights from the four corners of a dark room using 20 flash lights and a camera positioned exactly on the top of the surface in the middle of the room. The first light goes on and the image is acquired. This procedure continues for all flash lights in 19s.The acquired images were evaluated by Matlab application. With the new WMS system flash lights are replaced by 32 RGB COB LED lights using the DMX512 protocol to communicate with them. The system runs in 9s which is half the time of the old WMS system. New LabView and Matlab codes were adjusted to the new parameters and devices. In the end, measurements were taken with different surfaces, exposure times and color lights. Details of the new devices and software are analyzed in this thesis.
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Šunka, Pavel. "Aplikace FPGA v řízení maticových displejů LED." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-376970.
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The thesis gives an overview of the issue of control of full-color RGB LED panels with a large number of rows and columns. It deals with communication protocols for image transfer and information exchange. It focuses on implementing the FPGA into the RGB LED control structure. In the first half, the thesis focuses on deepening the theoretical knowledge about LED technologies, their control and color display. It further solves communication with superior elements. The last part of the theory is dedicated to FPGA circuits. The second part of the thesis describes the practical design of the FPGA circuit from UART and SPI communication through data storage from the communication to the panel control itself.
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Medrano, Arias Eduardo Alfredo. "Rediseño e implementación de un sistema de iluminación para espacios publicitarios usando Led RGB." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2010. http://tesis.pucp.edu.pe/repositorio/handle/123456789/509.
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Los sistemas de iluminación son desarrollos que permiten al hombre visualizar de una mejor
forma a los objetos desde un punto de vista artístico y funcional. Estos sistemas tienen un
amplio campo de aplicación en nuestra vida diaria. Están referidos al proceso en el cual la
iluminación forma parte del diseño del objeto usando dispositivos capaces de satisfacer el tipo,
calidad y color de luz que se requiere.
Dado que en el Perú los sistemas de iluminación cumplen una gran importancia como elemento
que forma parte del diseño de espacios públicos y comerciales, es necesario enfrentar el
problema de la iluminación conociendo las características de ella. Por esto se plantea la
utilización de una nueva tecnología como el LED (Light-Emitting Diode) de potencia en el
desarrollo de sistemas de iluminación aprovechando las características que este dispositivo
trae.
La presente tesis consiste en el rediseño e implementación de un sistema de iluminación
aplicado a un display1 publicitario de una superficie de 25x25cm2. Uno de los objetivos es
mejorar la iluminación mediante la aplicación de la nueva tecnología, el LED RGB (Red Green
Blue) que permite obtener un color determinado, rojo, verde y azul; además de variar su
intensidad de brillo. Con el uso de lentes convergentes es posible mezclar los colores primarios
para obtener los colores secundarios; amarillos, cian y magenta; y el color blanco.
El siguiente documento se encuentra dividido en cuatro capítulos principales; el primero de
ellos explica la importancia de la iluminación publicitaria en espacios publicitarios.
El segundo capítulo brinda información sobre la evolución de los sistemas de iluminación
convencionales hasta llegar a la tecnología LED.
El tercer capítulo muestra las consideraciones para el rediseño e implementación del sistema,
los componentes elegidos, así como los cálculos y criterios de selección.
El último capítulo menciona los resultados obtenidos, análisis de costo y conclusiones finales.
Al final del documento se muestra las recomendaciones, sobre el rendimiento del sistema de
iluminación y como mejorarlo, las referencias utilizadas y en la sección de anexos hojas de
datos de los componentes utilizados.Tesis
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Palmqvist, Linnea, and Hillevi Nilsson. "Musikvisualisering med LED-kub." Thesis, Uppsala universitet, Institutionen för materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-412444.
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En 4x4x4 kub konstrueras av RGB LED's med integrerad drivrutin och via en Arduino styrs den av musiken som spelas. Arduinon får musiken som input och med hjälp av fouriertransform delas signalen upp i 128 logaritmiskt uppdelade bins. Efter många olika teorier om hur bas, volym och känsla skulle kunna bestämmas i Arduinon bestämdes slutligen att de skulle bero av olika frekvensintervall; basen i 50-250 Hz, volymen i 500-2000 Hz och känslan i 2000-4000 Hz. Basen förflyttar mönstret framåt, volymen bestämmer ljusintensiteten (mellan 50% - 100% av max) och känslan avgör vilket av 6 mönster som aktiveras.
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Ashiabor, Awo Dede O. "A design for an RGB LED driver with independent PWM control and fast settling time." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/41251.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.Includes bibliographical references (leaves 76-77).
A small sized and efficient method to power RGB LEDs for use as backlights in flat panel displays is explored in this thesis. The proposed method is to drive a parallel switched connection of LEDs with a single Average Mode Controlled buck regulator.Specifications for the switching regulator and control circuitry are described. The application circuit demonstrates current settling times between 7[mu]s and 30[mu]s at a switching frequency of 290kHz. Current settling is improved at higher switching frequencies, with settling times approaching a 2[mu]s to 4[mu]s range at 1MHz switching.
by Awo Dede O. Ashiabor.
M.Eng.
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Stuchi, José Augusto. "Registro de imagens por correlação de fase para geração de imagens coloridas em retinógrafos digitais utilizando câmera CCD monocromática." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-18072013-110903/.
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A análise da retina permite o diagnostico de muitas patologias relacionadas ao olho humano. A qualidade da imagem e um fator importante já que o médico normalmente examina os pequenos vasos da retina e a sua coloração. O equipamento normalmente utilizado para a visualização da retina e o retinógrafo digital, que utiliza sensor colorido com filtro de Bayer e luz (flash) branca. No entanto, esse filtro causa perda na resolução espacial, uma vez que e necessário um processo de interpolação matemática para a formação da imagem. Com o objetivo de melhorar a qualidade da imagem da retina, um retinógrafo com câmera CCD monocromática de alta resolução foi desenvolvido. Nele, as imagens coloridas são geradas pela combinação dos canais monocromáticos R (vermelho), G (verde) e B (azul), adquiridos com o chaveamento da iluminação do olho com LED vermelho, verde e azul, respectivamente. Entretanto, o pequeno período entre os flashes pode causar desalinhamento entre os canais devido a pequenos movimentos do olho. Assim, este trabalho apresenta uma técnica de registro de imagens, baseado em correlação de fase no domínio da frequência, para realizar precisamente o alinhamento dos canais RGB no processo de geração de imagens coloridas da retina. A validação do método foi realizada com um olho mecânico (phantom) para a geração de 50 imagens desalinhadas que foram corrigidas pelo método proposto e comparadas com as imagens alinhadas obtidas como referência (ground-truth). Os resultados mostraram que retinógrafo com câmera monocromática e o método de registro proposto nesse trabalho podem produzir imagens coloridas da retina com alta resolução espacial, sem a perda de qualidade intrínseca às câmeras CCD coloridas que utilizam o filtro de Bayer.The analysis of retina allows the diagnostics of several pathologies related to the human eye. Image quality is an important factor since the physician often examines the small vessels of the retina and its color. The device usually used to observe the retina is the fundus camera, which uses color sensor with Bayer filter and white light. However, this filter causes loss of spatial resolution, since it is necessary a mathematical interpolation process to create the final image. Aiming at improving the retina image quality, a fundus camera with monochromatic CCD camera was developed. In this device, color images are generated by combining the monochromatic channels R (red), G (green) and B (blue), which were acquired by switching the eye illumination with red, green and blue light, respectively. However, the short period between the flashes may cause misalignment among the channels because of the small movements of the eye. Thus, this work presents an image registration technique based on phase correlation in the frequency domain, for accurately aligning the RGB channels on the process of generating retina color images. Validation of the method was performed by using a mechanical eye (phantom) for generating 50 misaligned images, which were aligned by the proposed method and compared to the aligned images obtained as references (ground-truth). Results showed that the fundus camera with monochromatic camera and the method proposed in this work can produce high spatial resolution images without the loss of quality intrinsic to color CCD cameras that uses Bayer filter.
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Guerreiro, Thiago Brito. "Desenvolvimento e aplicação de um fotômetro/fluorímetro microcontrolado à base de LED RGB para a determinação de espécies de interesse analítico." Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/7716.
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In this work, a photometer/fluorometer micro-controlled (P2FM) multifunctional, portable, communicated by USB 2.0, robust, easy handling and with low consumption of energy was developed. The P2FM was built using a micro-controlled (PIC-18F2455) as central unit of process (CPU), two tricolors LEDs (470, 528, 621 nm) as source of radiation, a multichannel sensor (TCS3200) and the management program wrote in Visual Studio. One of the two LED was used as radiation source for photometric mode. The TCS-3200 is a multichannel sensor with four photosensitive tracks: 480, 540, 750 e 830 nm, being that selection of track is performed by program controlled. The management program operates sending functions for microcontroller, record of dates and storage of signal (*.txt) through of USB port 2.0 (5.0 VCC, 300 mA). The P2FM is compact, with 3.5 cm × 7.0 cm × 8.5 cm size and 159.4 g of weight, considered as a portable device. In the program is selected of function mode: photometer or fluorimeter. In the analytic performance test by photometric mode, were used three solutions amaranth (AM), blue light (AB) and tartrazine (TT). The detection limits obtained were 1.6 × 10−7, 5.4 × 10−7 e 1.9 × 10−6 mol L−1 for AM, AB and TT, respectively. The quantification limits obtained were 4.8 × 10−7, 1.6 × 10−6 e 5.9 × 10−6 mol L−1 for AM, AB and TT, respectively. The correlation coefficients were AM = 0.997, AB = 0.975 and TT = 0.994. The analytic performance for fluorometric mode was carried using in both fluorescein (FL) and Rodamine 6G (R6G) solutions, were obtained a detection limit of 8.3 × 10−8 and 4.79 × 10−8 mol L−1, respectively for FL and R6G. The correlations coefficients were 0.997 for FL and 0.999 for R6G. Also, the proposed device was successfully used to sulphite determination in drinks, total hardness in water, determination of stability constant and study of stoichiometry of a chromogenic complex, aiming to show any applications of photometer/fluorimeter. The constant of formation obtained was 5.04 × 1018 is concordant with that presented in previous reports 6.2 × 1018. In sulphite determinations on eight samples of drinks, the paired studen’s t-test showed that reference method and photometric method using P2FM was 0.66 times smaller than critic value (2.36, α = 0.05). The total hardness in water was determined by fluorometric method, being that the P2FM showed best sensibility 8.94 × 106 that a determination using the RF5301/PC spectrofluorometer. The paired studen’s t-test (α = 0.05) no showed significant differences, calculated t (0.36) small than tabulated t (2.01).
Um fotômetro/fluorímetro microcontrolado (P2FM) multifuncional, portátil, comunicado via USB 2.0, robusto, de fácil operação e com baixo consumo de energia foi desenvolvido neste trabalho. O P2FM foi construído utilizando-se um microcontrolador (PIC-18F2455) como unidade central de processamento (CPU), dois LEDs tricolores (470, 528, 621 nm) como fonte de radiação, um sensor multicanal (TCS3200), e o programa de gerenciamento escrito em Visual Studio. Um dos LED foi utilizado como fonte de radiação para o modo fotométrico e o outro para o modo fluorimétrico. O TCS-3200 é um sensor multicanal com quatro faixas fotossensíveis: 480, 540, 750 e 830 nm, sendo que a seleção da faixa é realizada via programa de controle. O programa de gerenciamento atua no envio de funções para o microcontrolador, registro de dados e armazenamento do sinal (*.txt) através da porta USB 2.0 (5,0 VCC, 300 mA). O P2FM é compacto, com dimensões de 3,5 cm × 7,0 cm × 8,5 cm e massa de 159,4 g, configurando-se um instrumento portátil. No programa é selecionado o modo de funcionamento: fotométrico ou fluorimétrico. Nos testes de desempenho analítico no modo fotométrico foram empregadas soluções dos corantes amaranto (AM), azul brilhante (AB) e tartrazina (TT). Os limites de detecção obtidos foram 1,6 × 10, 5,4 × 107 e 1,9 × 106 mol L1 para AM, AB e TT, respectivamente. Os limites de quantificação obtidos foram 4,8 × 107, 1,6 × 10 e 5,9 × 106 mol L1 para AM, AB e TT, respectivamente. Os coeficientes de correlação foram: AM = 0,997, AB = 0,975 e TT = 0,994. O desempenho analítico no modo fluorimétrico foram realizados empregando-se soluções de fluoresceína (FL) e Rodamina 6G (R6G), sendo obtidos um limite de detecção de 8,3 × 108 e 4,79 × 108 mol L1, respectivamente para FL e R6G. Os coeficientes de correlação foram 0,997 para FL e 0,999 para R6G. Ademais, o instrumento proposto foi aplicado com sucesso na determinação de sulfito em bebidas, dureza total em água e determinação da constante de estabilidade e estequiometria de um complexo cromogênico, objetivando mostrar algumas aplicações do fotômetro/fluorímetro. A constante de formação obtida (5,04 × 1018) está em consonância com aquela apresentada na literatura, 6,2 × 1018. Na determinação de sulfito em oito amostras de bebidas, o teste t-pareado mostrou que método de referência e o método fotométrico usando P2FM foi de 0,66 menor do que o valor crítico (2,36, α = 0,05). A dureza da água foi determinada empregando-se o método fluorimétrico, sendo que o P2FM apresentou melhor sensibilidade 8,94 × 106 que a determinada empregandose o espectrofluorímetro (RF5301/PC). O teste t-pareado (α = 0,05) mostrou que não há diferença significativa, t critico (0,36) menor que o t crítico (2,01).
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Pontes, Aline Santos de. "Desenvolvimento de um fotômetro LED-Vis portátil e microcontrolado por Arduino." Universidade Federal da Paraíba, 2014. http://tede.biblioteca.ufpb.br:8080/handle/tede/7136.
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Previous issue date: 2014-04-28Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
A portable and low-cost photometer is proposed in this work. The instrument uses a tri-color light emitting diode (LED) as its radiation source in maximum emission wavelengths of 480 (blue), 534 (green) and 630 nm (red). It employs a phototransistor with spectral sensitivity in the visible region, as well as an Arduino microcontroller. Its analytical performance was evaluated by means of quantitative analysis (analytical curves), whose models were validated by analysis of variance (ANOVA). The instrument was applied to determine sunset yellow dye in energy drinks and sodas, and potassium permanganate pills. For comparison purposes, a commercial spectrophotometer was used to construct the calibration curves for the reference method. Applying the paired t-test at a 95 % confidence level for the concentration results obtained with the two instruments, we observed no statistically significant difference. Furthermore, accurate concentration estimates were obtained for the analytes as confirmed by the low relative standard deviation range of 0.2 and 0.5%, respectively, for both the dye and the permanganate. The proposed photometer might be an economically viable alternative to spectroscopic analysis, especially in teaching laboratories with limited financial resources or lacking in highly qualified personnel.
Um fotômetro portátil e de baixo custo é proposto neste trabalho. Esse instrumento utiliza um diodo emissor de luz (LED-Light Emitting Diode) tricolor como fonte de radiação nos comprimentos de onda do máximo de emissão de 480 (azul), 534 (verde) e 630 nm (vermelho). Além disso, emprega um fototransistor com sensibilidade espectral na região do visível como fototransdutor, bem como um microcontrolador Arduino como unidade de controle. Seu desempenho analítico foi avaliado por meio de análises quantitativas baseadas em curvas analíticas, cujos modelos foram validados por meio da Análise de Variância (ANOVA). O instrumento foi aplicado à determinação do corante amarelo crepúsculo em amostras de refrigerantes e bebidas energéticas e de permanganato de potássio em amostras de medicamentos. Para fins de comparação, um espectrofotômetro comercial foi empregado para construir as curvas analíticas do instrumento de referência. Aplicando o teste t-emparelhado ao nível de 95% de confiança para os resultados de concentração obtidos com os dois instrumentos, observa-se que não houve diferença estatisticamente significativa. Ademais, resultados precisos nas estimativas das concentrações dos analitos foram obtidos sendo atestado pelo baixo desvio padrão relativo conjunto de 0,2 e 0,5%, respetivamente, para o corante e permanganato. O fotômetro proposto pode ser uma alternativa economicamente viável para análises espectrométricas, sobretudo, em laboratórios de ensino com poucos recursos financeiros e carentes de pessoal altamente qualificado.
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Bastin, Guillaume. "Les résidus cystéines en positions 2 et 12 de RGS4 influencent son trafic intracellulaire et ses fonctions." Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10003/document.
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Les protéines RGS (Regulator of G-protein Signaling) sont des inhibiteurs des voies de signalisation des protéines G. RGS4 atténue l’activité de protéines G dans plusieurs tissus tel que la diminution de son activité peut accroître la sévérité de la bradycardie, cardiomyopathies liées au diabète, l’invasion de cellule cancéreuse du sein, résistance à l’insuline et intolérance au glucose. RGS4 a été localisé à la membrane plasmique ainsi que dans des compartiments intracellulaires, cependant, son mode de trafique intracellulaire reste méconnu. En utilisant des outils de microscopie confocale sur cellules vivantes et méthode de détection d’activité des voies de signalisation conditionnée par les protéines G, nous avons caractérisé l’importance de deux sites de palmitoylation, ces deux sites : Cys2 et Cys12 montrent des intérêts complémentaires dans le trafic de RGS4 vers la membrane cellulaire. Dans un axe linéaire, nous avons identifié DHHC3 et 7, deux enzymes de palmitoylation participant au trafique intracellulaire de RGS4 et donc à la maximalisation de son activité inhibitrice des voies de signalisation contrôlées par Galphaq. Enfin des marqueurs de membranes endosomales, les protéines rab ont permis de caractériser les voies de trafic intracellulaire empruntée par RGS4, par exemple RGS4 est internalisé de la membrane plasmique par Rab5 et recyclé à la membrane cellulaire par Rab11. L’activation ou inhibition de Rab5 et 11 ont permis d’observer des changements d’activité de RGS4. Ces travaux confèrent une base de données pour des études ultérieures visant à développer des stratégies thérapeutiques à accroître les fonctionnalités de RGS4RGS proteins (Regulator of G-protein Signaling) are potent inhibitors of heterotrimeric G-protein signaling. RGS4 attenuates G-protein activity in several tissues such that loss of its function may lead to bradycardia, diabetic cardiomyopathy, breast cancer cell invasion, insulin resistance and glucose intolerance. RGS4 has been localized to both plasma membrane and intracellular pools, however, the nature of its intracellular trafficking remains to be elucidated. G-protein inhibition requires the presence of RGS4 at the plasma membrane. In this work, we characterized the complementary roles of two putative palmitoylation sites on RGS4 to target intracellular compartments and plasma membrane. We identified palmitoylation on Cys2 and 12 respectively important for RGS4 endosomal targeting and plasma membrane localization, when mutations were introduced to the palmitoylation sites, RGS4 capability of inhibiting Gq-mediated signaling was impaired. As a continuum we identified two palmitoylating enzymes, DHHC3 and 7 as modulator of RGS4 localization and function. Knock downs of DHHC3 and 7 impaired RGS4 endosomal and plasma membrane targeting and capability of inhibiting M1-muscarinic receptor signaling. Finally we used live cell confocal microscopy to define RGS4 intracellular trafficking routes. Specifically Rab5 mediated RGS4 trafficking from the plasma membrane to intracellular compartments while Rab11 mediated RGS4 trafficking to the plasma membrane. Activation and inhibition of Rab5 and 11 routes impaired RGS4 capability of inhibiting M1-muscarinic receptor signaling pathway. These novel findings provide a strong rationale for future studies aimed at developing new strategies to increase the function of RGS4
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Dai, Yushuang. "Large eddy simulation of labyrinth seals and rib shapes for internal cooling passges." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/271753.
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The turbine is one of the key components in gas turbine engines. To prevent the turbine blades from being badly damaged by their harsh working environment, it is necessary to keep them cool. This can be achieved by enhancement of the heat transfer performance through internal cooling passages. However, the large quantity of flow within this internal cycle inevitably results in mass flow loss, which is a major source of loss in turbomachinery. Therefore labyrinth seals are also investigated in this study, attempting to reduce the flow leakage and further increase the turbine efficiency. Large Eddy Simulation ( LES ) is used for its capability to capture the complex unsteady flow features in this study. Different rib shapes in a fully developed ribbed channel are investigated, aiming to improve the heat transfer performance. An immersed boundary method ( IBM ) is used with LES to generate complex geometries. With the use of IBM , the range of geometries can be represented on a background Cartesian grid. To obtain the best sealing performance, an investigation is undertaken into the possibility of optimising labyrinth seal planforms using a genetic algorithm ( GA ). By making use of the large number of populations, a much faster calculation can be achieved toward the objective function. Three hundred LES calculations are carried out, and an optimised design is generated that maximises the sealing effectiveness. The optimised design shows a leakage reduction of about 27.6% compared to the baseline geometry. The optimisation process employing a GA will be continued. It is expected that automated optimisation as presented will become increasingly important in the design process of future turbomachines, particularly for flows with strong parameter interactions, with an aim to further improve the overall efficiency of gas turbines.
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Palacios, Ana. "Processus de transport et nucléosynthèse dans les étoiles évoluées." Toulouse 3, 2002. http://www.theses.fr/2002TOU30174.
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Dans le cadre du problème de l'étude des "anomalies d'abondances" observées à la surface des étoiles géantes rouges, ce travail de thèse a consisté à étudier les effets de la rotation sur le transport du moment cinétique et des espèces chimiques au cours de l'évolution des étoiles de faible masse. Après avoir déterminé les caractéristiques que doit avoir le mélange non-standard pour reproduire les observations, j'ai inclus dans le code d'évolution stellaire STAREVOL, le traitement du transport rotationnel dans les intérieurs radiatifs stellaires sous l'action combinée de la circulation méridienne et de la turbulence. Si ces processus permettent de reproduire les observations du côté chaud de la brèche du lithium, ils se sont avérés être inefficaces à modifier les abondances de surface des géantes rouges. Nous proposons cependant un scénario physique auto-cohérent, utilisant la rotation comme détonateur d'une série d'évènements permettant de reproduire une grande partie des observationsIn this thesis, we have studied the effects of rotation on the transport of angular momentum and chemicals all along the evolution of low-mass stars. This work was done within the framework of the study of abundance anomalies observed at the surface of low mass red giant stars. I have first determined the properties required for the non-standard mixing to account for the observations. I have then implemented the treatment of rotation-induced transport through meridional circulation and turbulence in stellar radiative interiors in the STAREVOL stellar evolution code. While these processes can account for observations on the hot side of the lithium dip, they appeared to fail in changing the surface abundances of low mass red gieant stars. We nevertheless propose a physical and self-consistent scenario, using rotation as the trigger to a series of events leading to the observed patterns
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Baldárrago, Catcoparco Jhair Andree. "Diseño de efectos y variación de colores mediante degradé en leds de potencia RGB aplicados a paneles publicitarios." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2010. http://tesis.pucp.edu.pe/repositorio/handle/123456789/527.
Full textAbstract:
En el presente trabajo se realizó el diseño de efectos con colores mediante
degradés en una matriz de LEDs de potencia RGB orientado a paneles publicitarios,
con el objetivo de implementar este sistema de iluminación como una opción frente
a los métodos tradicionales, pues estos últimos ofrecen muchas desventajas, tanto
en la parte visual como en la parte económica. Además de incluir en el diseño, una
interfaz para ser operada por un usuario, de manera fácil e intuitiva, la cual
actualmente no es brindada por los equipos comerciales que ofrecen este tipo de
iluminación, pues estos ya vienen predeterminados desde su fabricación.
El diseño realizado consta de 2 partes. La primera parte es el desarrollo del
software, es decir, el programa cuyo fin es lograr el degradés de los colores, así
como los efectos realizados con estos; mientras que la segunda parte es el
hardware, lo que incluye tanto los controladores de potencia para los LEDs, como
los LEDs mismos y la tarjeta de control de todo el sistema. Ambas partes, así como
la investigación previa, están documentadas en 4 capítulos.
En el primer capítulo, se definen los métodos de publicidad visual, dentro de los
cuales se encuentra la publicidad exterior (paneles), así como la visión humana y
sus características en función a los colores.
Luego, en el segundo capítulo, se muestra el estado actual de la iluminación con
LEDs de potencia RGB, su funcionamiento y aplicaciones actuales en la industria.
En el tercer capítulo, se desarrolla el diseño planteado para cubrir los objetivos,
tanto en la parte de hardware (controladores, LEDs de potencia, etc.) como en
software (desarrollo de programa).
Finalmente, en el cuarto capítulo, se presentan las simulaciones y fotografías, las
cuales prueban en correcto funcionamiento de los subsistemas que conforman la
iluminación con LEDs, así como el sistema integral conjunto.
Además, en la última parte se presentan las conclusiones y recomendaciones en el
desarrollo del prototipo presentado, para que puedan ser tomadas en cuenta para
futuras mejoras de este.Tesis
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Luiz, Vitor Hugo Marques [UNESP]. "Desenvolvimento de procedimentos e métodos analíticos no campo forense aplicando os princípios da química verde." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/136238.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho descreve o desenvolvimento de métodos analíticos para a determinação quantitativa de furosemida e bumetanida em amostras de urina utilizando espectroscopia por reflectância difusa (para a furosemida) e por imagem por scanner com quantificação através do histograma de cores utilizando o padrão RGB (para ambas). Envolve também o desenvolvimento de um método quantitativo para a detecção de chumbo em resíduos de armas de fogo (GSR) nas mãos de atiradores utilizando membranas de celulose bacteriana como substrato de coleta, visando o descobrimento do tempo de disparo. Também foi realizada a quantificação de chumbo em amostras de tintura para cabelos utilizando método previamente desenvolvido, visando detecção da adulteração destes produtos e controle de qualidade. Estuda também a potencialidade do uso das membranas de celulose bacteriana para a coleta de impressões digitais. Os métodos desenvolvidos consistem na reação da furosemida (FUR) com o regente cromogênico paradimetilaminocinamaldeído (p-DAC) 0,70% e ácido clorídrico (HCl) 1,72 mol L-1 em papel de filtro qualitativo com barreiras hidrofóbicas, com detecção espectrofotométrica e por histograma de cores; na reação do íon chumbo(II) (Pb2+) com rodizonato de sódio (ROD) 0,16% em meio micelar de dodecil sulfato de sódio (SDS) 5 mmol L-1 em membranas de celulose bacterianas, com detecção espectrofotométrica e por microscopia eletrônica de varredura (MEV); na reação de bumetanida (BMT) com o reagente p-DAC 0,6% e HCl 0,26 mol L-1 em papel de filtro qualitativo com barreiras hidrofóbicas, com detecção por histograma de cores e na coleta de impressões digitais utilizando membrana de celulose bacteriana impregnadas com ninidrina, nitrato de prata ou óxido de zinco, dos quais o nitrato de prata e a ninidrina atuaram como agentes de coleta razoáveis. Todas as concentrações foram otimizadas por planejamentos quimiométricos. As reações foram realizadas na forma de spot test, envolvendo a formação de um produto colorido em 545 nm para o chumbo, em 585 nm para a furosemida e 520 nm para a bumetanida. As curvas analíticas foram contruídas a partir de soluções padrões dos respectivos analitos. Os métodos desenvolvidos para a bumetanida e para a furosemida foram aplicados em amostras de urina sintética e natural fortificadas e os resultados obtidos foram comparados estatisticamente com métodos comparativos. A validação dos métodos foi realizada por adição de padrão e recuperação e por comparação de métodos, no caso da FUR e da BMT, obtendo-se recuperações entre 98,0 e 115,3% para os métodos de quantificação da furosemida e entre 93,0 e 102,0% para o método de quantificação da bumetanida. O método de coleta de GSR é baseado na utilização de membranas finas de celulose bacteriana desenvolvidas pelo Grupo de Materiais Fotônicos do IQ-UNESP.Para os GSR foram realizadas 40 coletas totais em tempos de coleta após o disparo (diferentes e conhecidos), sendo sua comparação realizada através das curvas analíticas, mostrando ser possível a detecção do tempo de disparo com uma margem de erro de aproximadamente 5 minutos. Os resultados foram comparados estatisticamente e os valores obtidos a partir de testes estatísticos mostraram que os métodos podem ser usados para análises de rotina em laboratórios forenses.
This work describes the development of analytical methods for the quantitative determination of furosemide and bumetanide in urine samples using diffuse reflectance spectroscopy (for furosemide) and scanning imaging with quantification by color histogram using RGB color pattern (for both). It involves also the development of a quantitative method for the detection of lead in gunshot residues (GSR) in the hands of the shooters using bacterial cellulose membranes as substrate collection, aiming the discovery of shooting time. It is also done the quantification of lead in progressive hair lotions samples using a previously developed method, aiming the detection of products adulterations and quality control. It also studies the potentiality of the usage of bacterial cellulose membranes for the collection of fingerprints. The developed methods are consisted in the reaction of furosemide (FUR) with the cromogenic reagent p-dimethylamino cinnamaldehyde (p-DAC) 0.70% and hydrochloric acid (HCl) 1.72 mol L-1 in qualitative filter papers with hydrophobic barrier, with spectrophotometric detection and by color histogram; in the reaction of lead(II) ion (Pb2+) with sodium rhodizonate (ROD) 0.16% in micellar medium of sodium dodecyl sulfate (SDS) 5 mmol L-1 in bacterial cellulose membranes with spectrophotometric detection and by scanning electron microscopy; in the reaction of bumetanide (BMT) with the reagent p-dimethylamino cinnamaldehyde (p-DAC) 0.6% and hydrochloric acid (HCl) 0.27 mol L-1 in qualitative filter papers with hydrophobic barrier with color histogram detection an in the collect of fingerprints using bacterial cellulose membranes impregnated with ninhydrine, silver nitrate or zinc oxide, of which the silver nitrate and ninhydrin acted as reasonable collection agents. All concentrations were optimized through chemometrics designs. The reactions were carried out as spot test, involving the formation of a colored product at 545 nm for lead, in 585 nm for furosemide and in 520 nm for bumetanide. Analytical curves were built from standard solutions of the respective analytes. The methods developed for furosemide and bumetanide were applied in fortified synthetic and natural urine samples and the results obtained were compared statistically with comparative methods. The validation of the methods were performed by standard addition and recovery and by comparison of methods, for FUR and BMT, yielding recoveries between 98.0 and 115.3% for furosemide quantification methods and between 93.0 and 102.0% for the quantification method for bumetanide. GSR collection method is based on the use of thin membranes of bacterial cellulose developed by Photonic Materials Group IQ-UNESP. For GSR, 40 total collections were carried out in known and different times of collection after shooting times and their comparison through analytical curves were done, showing the possibility of the detection of the shooting time with an error of 5 minutes, approximately. The results were statistically compared and the values obtained from statistical tests showed that the methods can be used for routine analysis in forensic laboratories.
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Souza, José Antonio Batista de. "Estudo do processo de fabricação de alvos de folhas finas de urânio metálico para produção de Mo-99." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-29112018-081047/.
Full textAbstract:
O Tecnécio-99m (99mTc), gerado a partir do decaimento do Molibdênio-99 (99Mo), é o radionuclídeo mais conveniente para a execução de procedimentos de diagnósticos médicos, devido à sua emissão gama bem característica e de fácil detecção. O método utilizado para produzir 99Mo é através da fissão do 235U incorporado nos chamados alvos de irradiação. Duas rotas estão sendo desenvolvidas para a produção do 99Mo por fissão para o Reator Multipropósito Brasileiro (RMB), ambas utilizando urânio de baixo enriquecimento (LEU): 1) A primeira a dissolução básica, que é baseada na tecnologia de alvos de dispersão UAlx-Al. 2) A segunda emprega a dissolução ácida de alvos de folhas finas de urânio metálico. A principal vantagem dos alvos de folha fina de urânio metálico sobre os alvos de dispersão UAlx-Al é a alta densidade do urânio metálico. Com o intuito de compreender e otimizar o processo de fabricação de alvos de folhas finas foi realizado um estudo da fusão do urânio metálico, laminação de folhas finas, caracterização microestrutural e montagem dos alvos, definindo assim, os procedimentos específicos para a produção desse tipo de alvo com as características dos alvos fabricados internacionalmente. Os resultados obtidos mostraram que o processo de fabricação dos lingotes e de lâminas de urânio metálico por meio de laminação a quente possibilitaram a obtenção de lâminas com espessura entre 250 e 300 μm. O processo de laminação a frio possibilitou a obtenção de folhas finas com espessura de ±125 μm que atende à especificação internacional. O uso de óxido de alumínio como material para prevenir caldeamento do tablete de urânio mostrou-se eficiente, substituindo com vantagens o uso de óxido de ítrio. A microestrutura após o tratamento térmico apresentou grãos equiaxiais pequenos, e a realização de um resfriamento rápido de 5 minutos após o tratamento térmico foi suficiente para se eliminar a textura da folha fina de urânio metálico. O processo de montagem das folhas finas no alvo tubular foi realizado por pré-conformação da folha fina, facilitando a montagem. O processo de consolidação do alvo foi realizado por expansão por tração e a folga após a consolidação (\"gap de ar\") mostrou-satisfatória. As dimensões finais dos alvos tubulares atenderam à especificação internacional.Technetium-99m (99mTc) is generated from the decay of Molybdenum-99 (99Mo). This element is the most convenient radionuclide for application in medical diagnostic procedures, once that its gamma emission is well known and of easily detected. The method used to produce 99Mo is through fission of the 235U embedded in so-called irradiation targets. Two routes are being developed for the production of 99Mo per fission to the Brazilian Multipurpose Reactor (RMB), both using low enriched uranium (LEU): 1) The first basic dissolution, which is based on the technology of dispersion targets UAlx-Al. 2) The second employs the acidic dissolution of thin sheet targets of metallic uranium. The main advantage of uranium metal foil targets on the UAlx-Al dispersion targets is the high density of metallic uranium. In order to understand and optimize the process of manufacturing thin sheet targets, about the fusion of metallic uranium, thin sheet lamination, microstructural characterization and assembly of the target was carried out. Therefore the specific procedures for the production of this type of target with the characteristics of the targets manufactured internationally could be defined. The results showed that the process of manufacturing ingots and sheets of metallic uranium by hot rolling allows obtaining sheets with thickness between 250 and 300 μm. The cold rolling process allows obtaining thin sheets with a thickness of ± 125 μm which are in accordance with the international specification. The use of aluminum oxide as a material to prevent uranium tablet firing proved to be efficient, replacing with advantage the use of yttrium oxide. The microstructure after the heat treatment showed small equiaxial grains. A fast cooling of 5 minutes after the heat treatment was enough to eliminate the texture of the thin sheet of metallic uranium. The process of assembling the thin sheets in the tubular target was performed by preforming the thin sheet, facilitating the assembly. The process of consolidating the target was performed by tensile expansion and the clearance after consolidation (\"air gap\") was satisfactory. The final dimensions of the tubular targets have met the international specification.
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Lara, Alvarado Carlo Manuel. "Diseño de un sistema de iluminación para espacios publicitarios pequeños usando Leds de potencia RGB / Carlo Manuel Lara Alvarado." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2009. http://tesis.pucp.edu.pe/repositorio/handle/123456789/258.
Full textAbstract:
Debido al acelerado desarrollo de los semiconductores, en los últimos 15 años, se
ha logrado dejar de usar a los LEDs como simplemente fuentes de señalización en
diversas aplicaciones minúsculas, por ejemplo en los muy conocidos displays de 7
segmentos o como puntos brillantes en los teclados y circuitos electrónicos, para
pasar con fuerza al ámbito de la iluminación. Es así, como grandes empresas
internacionales han fijado su interés en el desarrollo y afianzamiento en el mercado
de los llamados LEDs de potencia o alto brillo, dado que, como su nombre lo indica,
han llegado a multiplicar su capacidad de generar luz y mejorar su eficiencia
luminosa hasta el punto de competir y superar otros tipos tradicionales de fuentes
de iluminación.
Es por estas razones, que el objetivo de este trabajo de tesis es diseñar un sistema
de iluminación usando LEDs de potencia RGB para espacios publicitarios de
tamaño pequeño, ya que el ámbito de la publicidad es un mercado donde se
permite aplicar todo el potencial de una nueva tecnología de iluminación multicolor.Tesis
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Mikkelsen, Markus, and Gustav Svanfors. "Mätning av LCD-bildskärmars responstid och latens : Measurement of LCD displays response time and input lag." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-26555.
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Examensarbetet har utförts i samarbete med företaget LVI (Low Vision International) som tillverkar elektroniska hjälpmedel för synskadade. LVI utvärderar vid jämna mellanrum nya LCD-bildskärmar för deras produkter. LVI behöver metoder samt utrustning för att mäta bildskärmars responstid och latens. Både responstiden och latensen ger fördröjningar vilket t.ex. leder till att bilden blir oskarp, rörliga föremål får en svans efter sig eller att lju- det kommer före bilden. I detta arbete utförs en grundlig förstudie som behandlar bild- skärmars responstid och latens samt ger ett underlag för att konstruera eller köpa mätut- rustning för responstidsmätningar. I förstudien framkommer den standardiserade mätmeto- den ”grey-to-grey” som LVI kan använda för att mäta responstiden. En mätkrets konstrue- ras för att mäta responstiden samt beställs en dedikerad enhet för latensmätning. För att ut- värdera mätmetoderna utförs ett antal tester med mätkretsen för responstid och den dedike- rade enheten för mätning av latens. Mätningarna visar senare att mätmetoden ”grey-to- grey” är den som LVI ska använda men metoden behöver vidareutvecklas. Den dedikerade enheten för latensmätningar visar sig mäta en del av responstiden och bör därför endast an- vändas som komplement till responstidsmätningen vid jämförelser mellan olika bildskär- mar. Arbetet levererar en förstudie i LCD-bildskärmars responstid och latens, en vidareut- vecklad version av ”grey-to-grey”-metoden, mätutrustning för responstidsmätning samt den dedikerade mätenheten för latens till företaget LVI.The thesis was performed in collaboration with the company LVI (Low Vision Interna- tional) that manufactures electronic devices for the visually impaired. LVI evaluates new LCD displays for their products at regular intervals. LVI need methods and equipment for measuring response time and input lag. Both response time and input lag cause delays, which results in such things as image blur, ghosting after moving objects or a delay between sound and image. The preliminary study reveals the standardized method “grey- to-grey” that LVI can use to measure response time. A measurement circuit was constructed to measure response time and a dedicated unit for input lag measurement was ordered. To evaluate the measurement methods a number of tests were conducted with the response time circuit and the dedicated input lag unit. The measurements showed that the method LVI shall use is the "grey-to-grey” method but it needs further development. It turned out that the dedicated unit for input lag measured a portion of the response time and should therefore only be used as a complement to the response time measurement when comparing displays. The thesis delivers a preliminary study in LCD displays response times and input lag, a further developed version of the “grey-to-grey” method, measurement equipment for response time and a dedicated unit for input lag measurements to the company LVI.
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Mayo, Yague Ignacio. "Flow field and heat transfer in a rotating rib-roughened cooling passage." Phd thesis, Toulouse, INPT, 2017. http://oatao.univ-toulouse.fr/19529/1/MayoYague_Ignacio.pdf.
Full textAbstract:
A great effort has been carried out over the recent years in the understanding of the flow field and heat transfer in the internal cooling channels present in turbine blades. Indeed, advanced cooling schemes have not only lead to the increase of the gas turbine efficiency by increasing the Turbine Inlet Temperature above the material melting temperature, but also the increase of the turbine lifespan. To allow such progresses, modern experimental and numerical techniques have been widely applied in order to interpret and optimize the aerodynamics and heat transfer in internal cooling channels. However, the available data is limited in the case of internal cooling channels in turbine rotor blades. Rotation and temperature gradients introduce Coriolis and centripetal buoyancy forces in the rotating frame of reference, modifying significantly the aerothermodynamics from that of the stationary passages. In the case of turbine rotor blades, most of the investigations are either based on point-wise measurements or are constraint to low rotational regimes. The main objective of this work is to study the detailed flow and heat transfer of an internal cooling channel at representative engine dimensionless operating conditions. This work introduces a laboratory test section that operates ribbed channels over a wide range of Reynolds, Rotation and Buoyancy numbers. In the present work, the Reynolds number ranges from 15,000 to 55,000, the maximum Rotation number is equal to 0.77, and the maximum Buoyancy number is equal to 0.77. The new experimental facility consists in a versatile design that allows the interchangeability of the tested geometry, so that channels of different aspect ratios and rib geometries can be easily fitted. Particle Image Velocimetry and Liquid Crystal Thermography are performed to provide accurate velocity and heat transfer measurements under the same operating conditions, which lead to a unique experimental data set. Moreover, Large Eddy Simulations are carried out to give a picture of the entire flow field and complement the experimental observations. Additionally, the numerical approach intends to provide a robust methodology that is able to provide high fidelity predictions of the performance of internal cooling channels.
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TOUCHOT, NICOLAS. "Les proteines rab : une famille de petites proteines g impliquees dans les transports intracellulaires." Paris 6, 1989. http://www.theses.fr/1989PA066720.
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Nous avons developpe une strategie utilisant les oligonucleotides de synthese pour isoler de nouveaux membres de la superfamille ras. Plusieurs clones correspondant a des genes differents ont ainsi ete isoles de banques d'adnc d'origine humaine ou murine. Ils codent tous pour des polypeptides de 23-25 kd qui presentent de 30 a 92% d'identite et ont ete regroupes dans une nouvelle branche de la superfamille ras: la famille rab. Cette famille comprend egalement deux proteines de levure impliquees dans la regulation de la secretion chez cet organims: ypt1p et sec4p. L'expression en arnm des genes rab a ete etudiee dans les organes de souris adultes, et dans plusieurs lignees cellulaires. Nous avons egalement produit les proteines rab chez e. Coli et etudie certaines de leurs proprietes biochimiques: fixation du gtp et activite gtpase intrinseque. L'utilisation d'anticorps polyclonaux de lapins nous a permis de localiser les proteines rab dans plusieurs structures membranaires intracellulaires dont l'appareil de golgi et le reticulum endoplasmique. La fonction cellulaire des proteines rab ainsi que leur implication possible dans la regulation de la secretion cellulaire chez les mammiferes fait l'objet de la discussion
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Pham, Huy-Hieu. "Architectures d'apprentissage profond pour la reconnaissance d'actions humaines dans des séquences vidéo RGB-D monoculaires : application à la surveillance dans les transports publics." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30145.
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Cette thèse porte sur la reconnaissance d'actions humaines dans des séquences vidéo RGB-D monoculaires. La question principale est, à partir d'une vidéo ou d'une séquence d'images donnée, de savoir comment reconnaître des actions particulières qui se produisent. Cette tâche est importante et est un défi majeur à cause d'un certain nombre de verrous scientifiques induits par la variabilité des conditions d'acquisition, comme l'éclairage, la position, l'orientation et le champ de vue de la caméra, ainsi que par la variabilité de la réalisation des actions, notamment de leur vitesse d'exécution. Pour surmonter certaines de ces difficultés, dans un premier temps, nous examinons et évaluons les techniques les plus récentes pour la reconnaissance d'actions dans des vidéos. Nous proposons ensuite une nouvelle approche basée sur des réseaux de neurones profonds pour la reconnaissance d'actions humaines à partir de séquences de squelettes 3D. Deux questions clés ont été traitées. Tout d'abord, comment représenter la dynamique spatio-temporelle d'une séquence de squelettes pour exploiter efficacement la capacité d'apprentissage des représentations de haut niveau des réseaux de neurones convolutifs (CNNs ou ConvNets). Ensuite, comment concevoir une architecture de CNN capable d'apprendre des caractéristiques spatio-temporelles discriminantes à partir de la représentation proposée dans un objectif de classification. Pour cela, nous introduisons deux nouvelles représentations du mouvement 3D basées sur des squelettes, appelées SPMF (Skeleton Posture-Motion Feature) et Enhanced-SPMF, qui encodent les postures et les mouvements humains extraits des séquences de squelettes sous la forme d'images couleur RGB. Pour les tâches d'apprentissage et de classification, nous proposons différentes architectures de CNNs, qui sont basées sur les modèles Residual Network (ResNet), Inception-ResNet-v2, Densely Connected Convolutional Network (DenseNet) et Efficient Neural Architecture Search (ENAS), pour extraire des caractéristiques robustes de la représentation sous forme d'image que nous proposons et pour les classer. Les résultats expérimentaux sur des bases de données publiques (MSR Action3D, Kinect Activity Recognition Dataset, SBU Kinect Interaction, et NTU-RGB+D) montrent que notre approche surpasse les méthodes de l'état de l'art. Nous proposons également une nouvelle technique pour l'estimation de postures humaines à partir d'une vidéo RGB. Pour cela, le modèle d'apprentissage profond appelé OpenPose est utilisé pour détecter les personnes et extraire leur posture en 2D. Un réseau de neurones profond est ensuite proposé pour apprendre la transformation permettant de reconstruire ces postures en trois dimensions. Les résultats expérimentaux sur la base de données Human3.6M montrent l'efficacité de la méthode proposée. Ces résultats ouvrent des perspectives pour une approche de la reconnaissance d'actions humaines à partir des séquences de squelettes 3D sans utiliser des capteurs de profondeur comme la Kinect. Nous avons également constitué la base CEMEST, une nouvelle base de données RGB-D illustrant des comportements de passagers dans les transports publics. Elle contient 203 vidéos de surveillance collectées dans une station du métro incluant des événements "normaux" et "anormaux". Nous avons obtenu des résultats prometteurs sur cette base en utilisant des techniques d'augmentation de données et de transfert d'apprentissage. Notre approche permet de concevoir des applications basées sur des techniques de l'apprentissage profond pour renforcer la qualité des services de transport en communThis thesis is dealing with automatic recognition of human actions from monocular RGB-D video sequences. Our main goal is to recognize which human actions occur in unknown videos. This problem is a challenging task due to a number of obstacles caused by the variability of the acquisition conditions, including the lighting, the position, the orientation and the field of view of the camera, as well as the variability of actions which can be performed differently, notably in terms of speed. To tackle these problems, we first review and evaluate the most prominent state-of-the-art techniques to identify the current state of human action recognition in videos. We then propose a new approach for skeleton-based action recognition using Deep Neural Networks (DNNs). Two key questions have been addressed. First, how to efficiently represent the spatio-temporal patterns of skeletal data for fully exploiting the capacity in learning high-level representations of Deep Convolutional Neural Networks (D-CNNs). Second, how to design a powerful D-CNN architecture that is able to learn discriminative features from the proposed representation for classification task. As a result, we introduce two new 3D motion representations called SPMF (Skeleton Posture-Motion Feature) and Enhanced-SPMF that encode skeleton poses and their motions into color images. For learning and classification tasks, we design and train different D-CNN architectures based on the Residual Network (ResNet), Inception-ResNet-v2, Densely Connected Convolutional Network (DenseNet) and Efficient Neural Architecture Search (ENAS) to extract robust features from color-coded images and classify them. Experimental results on various public and challenging human action recognition datasets (MSR Action3D, Kinect Activity Recognition Dataset, SBU Kinect Interaction, and NTU-RGB+D) show that the proposed approach outperforms current state-of-the-art. We also conducted research on the problem of 3D human pose estimation from monocular RGB video sequences and exploited the estimated 3D poses for recognition task. Specifically, a deep learning-based model called OpenPose is deployed to detect 2D human poses. A DNN is then proposed and trained for learning a 2D-to-3D mapping in order to map the detected 2D keypoints into 3D poses. Our experiments on the Human3.6M dataset verified the effectiveness of the proposed method. These obtained results allow opening a new research direction for human action recognition from 3D skeletal data, when the depth cameras are failing. In addition, we collect and introduce in this thesis, CEMEST database, a new RGB-D dataset depicting passengers' behaviors in public transport. It consists of 203 untrimmed real-world surveillance videos of realistic "normal" and "abnormal" events. We achieve promising results on CEMEST with the support of data augmentation and transfer learning techniques. This enables the construction of real-world applications based on deep learning for enhancing public transportation management services
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Chabrillat, Marion. "Etude du mouvement des mélanosomes sur les filaments d' actine : rôle des protéines Rab8 et myosine VI." Paris 6, 2005. http://www.theses.fr/2005PA066391.
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LALEGERIE, FREDERIC. "Secretion des catecholamines par les cellules chromaffines : role potentiel de la petite proteine g rab 3." Paris 11, 1993. http://www.theses.fr/1993PA114235.
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Larkin, Heidi. "Rôle de Calnuc dans le triage endosomial des récepteurs lysosomiaux et implication potentielle dans les maladies du lysosome." Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8204.
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Résumé : Calnuc est une protéine ubiquitaire qui lie le calcium et qui est présente au réseau trans-golgien (TGN) ainsi qu'aux endosomes. Notre groupe a précédemment mis en évidence le rôle de Calnuc dans le transport de Low density lipoprotein receptor-related protein 9 (LRP9), un récepteur aux lipoprotéines de faible densité qui cycle entre le TGN et les endosomes. Les récepteurs lysosomiaux au mannose-6-phosphate (MPR) et Sortiline sont bien caractérisés et empruntent également cette voie. À l'image de LRP9, nous avons montré que Calnuc prévient leur dégradation aux lysosomes en participant à leur recyclage à partir des endosomes vers le TGN. En fait, Calnuc est importante pour l'activation et l'association membranaire de Rab7, une petite protéine G qui recrute ensuite le complexe Rétromère responsable du transport rétrograde des récepteurs. La glycoprotéine lysosomiale Ceroid lipofuscinosis neuronal 5 (CLN5) est également impliquée dans ce processus. La structure et la fonction de cette dernière n'étant pas clairement définies, nous avons établi qu'elle est synthétisée sous forme d’une glycoprotéine transmembranaire de type II, mais son domaine N-terminal cytoplasmique et son segment transmembranaire sont rapidement éliminés suivant le clivage du peptide signal de manière à former une protéine CLN5 mature fortement associée à la membrane par une hélice amphipathique (AH). La compréhension des propriétés de base de CLN5 est particulièrement pertinente puisque la protéine est impliquée dans certaines variantes de céroïdes-lipofuscinoses neuronales (NCL), une maladie neurodégénérative rare causée par une surcharge des lysosomes. D'ailleurs, nos données indiquent que les mutants pathologiques de CLN5 dépourvus de cette AH perdent leur association membranaire, sont retenus au réticulum endoplasmique et sont rapidement dégradés. En raison de la similitude des fonctions de Calnuc et de CLN5 au niveau du triage endosomial, nous avons exploré le lien entre les deux protéines. Calnuc cytosolique et CLN5 luminale semblent former un complexe, par l'intermédiaire de la protéine transmembranaire CLN3, de façon à influencer l'activité de Rab7. CLN3 étant aussi associée aux NCL, nous avons finalement exploré la potentielle implication de Calnuc dans la maladie. L'absence de Calnuc entraîne des phénotypes cellulaires typiques des NCL comme un engorgement des lysosomes, une accumulation de matériel autofluorescent et une augmentation de l'autophagie. Les niveaux protéiques de Calnuc sont diminués dans toutes les lignées de fibroblastes de patients atteints de NCL disponibles ce qui indique que Calnuc pourrait être impliquée dans certains types de NCL. La présente thèse couvre donc la découverte de la fonction de Calnuc dans le transport intracellulaire, jusqu'à son implication potentielle dans les NCL, de même qu'une étude topologique de CLN5.Abstract : Calnuc is a ubiquitous Ca2+-binding protein present on the trans-Golgi network (TGN) and endosomes. We previously highlighted the role of Calnuc in the transport of Low density lipoprotein receptor-related protein 9 (LRP9), a low density lipoprotein (LDL) receptor that cycles between the TGN and endosomes. Lysosomal receptors mannose-6-phosphate receptor (MPR) and Sortilin are well-characterized and also use the TGN-to-endosome trafficking pathway. Similarly to LPR9, we showed that Calnuc prevent their degradation in lysosomes by acting in their recycling from endosomes to the TGN. In fact, Calnuc is a important for the activation and the membrane association of Rab7, a small G protein which then recruit the Retromer complex known to be responsible for the retrograde transport of receptors. Lysosomal glycoprotein Ceroid lipofuscinosis neuronal 5 (CLN5) is also involved in this process. Because its structure and function have not yet been clearly defined, we established that it is synthesized as a type II transmembrane (TM) glycoprotein, but its cytoplasmic N-terminus and TM segment are rapidly removed following signal-peptide cleavage to generate mature CLN5 which is tightly associated to membrane through an amphipathic helix (AH). The understanding of the basic properties of CLN5 is particularly important given that CLN5 is involved in some variants of neuronal ceroid lipofuscinosis (NCL), a rare neurodegenerative disease caused by lysosomal overload. Moreover, our data indicate that CLN5 pathological mutants deprived of AH lose their membrane association, are retained in the endoplasmic reticulum, and are rapidly degraded. Based on the similarity featured by Calnuc and CLN5 in endosomal sorting, we explored the link between these two proteins. Cytosolic Calnuc and luminal CLN5 seem to form a complex, through the transmembrane protein CLN3, in order to influence the activity of Rab7. As CLN3 is also associated with NCL, we finally explored the potential involvement of Calnuc in this disease. Canuc depletion leads to typical NCL phenotypes such as lysosome enlargement, accumulation of autofluorescent material and of an increased of autophagy induction. Canuc's levels are decreased in all fibroblasts cell lines of NCL patients available indicating that Calnuc could be involved in some types of NCL. This thesis thus covers the discovery of the function of Calnuc in intracellular transport up to its potential involvement in the NCL, as well as a topological study CLN5.
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JOUANJAN, THIERRY. "Les acides amines ramifies en nutrition post-operatoire : etude experimentale du solute r.b. numero 1593." Lille 2, 1988. http://www.theses.fr/1988LIL2M041.
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Bruneau, Emmanuelle. "Les régulateurs transcriptionnels Rgg de Streptococcus thermophilus LMG18311 : étude du rôle de la protéine Rgg0182." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0139/document.
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Cette thèse a pour objectif la caractérisation des gènes rgg de S. thermophilus LMG18311 codant des régulateurs transcriptionnels et l'étude de leur implication dans l'adaptation à l'environnement. Ce travail montre que le gène rgg0182 code un régulateur transcriptionnel activant la transcription de ses gènes adjacents. Par ailleurs, le couple Rgg0182/Shp0182 participerait à un mécanisme de quorum sensing. De plus, la protéine Rgg0182 participe à la tolérance au stress chaud. En outre, les cellules du mutant [delta]rgg0182 présentent un phénotype d'adhésion thermo-induite via des interactions de types hydrophobes. L'analyse par microscopie à force atomique des cellules de la souche LMG18311 et du mutant [delta]rgg0182 révèle la présence de polymères de surface uniquement chez la souche sauvage, suggérant que la protéine Rgg0182 régulerait l'expression de protéines de surface et de la division cellulaire. Une étude protéomique couplée à une analyse transcriptomique ont permis d'identifier plusieurs cibles de Rgg0182 qui participeraient à diverses fonctions biologiques. L'ensemble des données obtenues démontre que la protéine Rgg0182 de S. thermophilus LMG18311 est un régulateur global de l'expression génique. Par ailleurs, la transcription des 7 gènes rgg présents au sein du génome de S. thermophilus LMG18311 est modulée par les conditions environnementales. Les profils de transcription des 7 gènes rgg diffèrent les uns par rapport aux autres, suggérant que chacun d'eux seraient requis dans des conditions de croissances différentes. Ces données posent l'hypothèse que les protéines Rgg participeraient à la régulation fine et complexe de l'expression génique de S. thermophilusThis thesis aims to characterize the rgg genes of S. thermophilus LMG18311 coding transcriptional regulator and their involvement in environmental adaptation. This work shows that rgg0182 gene encodes a transcriptional regulator controlling the transcription of its flanking genes. The Rgg0182/Shp0182 pair could be involved in a quorum sensing mechanism. This work also demonstrates that the Rgg0182 protein is involved in S. thermophilus tolerance to heat stresses. In addition, the mutant delta rgg0182 cells exhibit a thermo-induced adhesion phenotype via hydrophobic interactions. Analyses by atomic force microscopy of LMG18311 cells of the wildtype and its derivative rgg0182 mutant reveal the presence of polymers only on the surface of the wild-type strain, suggesting that the protein Rgg0182 would regulate the expression of surface proteins and proteins of cell division. A proteomic study coupled with transcriptomic analysis led to the identification of several targets of Rgg0182 involving in various biological functions. The data obtained in this work have shown that the S. thermophilus LMG18311 rgg0182 genes encodes a global regulator of gene expression. Furthermore, transcriptional analyses, in different growth conditions, of the 7 rgg genes present in the genome of S. thermophilus LMG18311 showed that they display different expression profiles that are modulated by environmental conditions. This suggests that these genes would be required in distinct growth conditions. These data raise the hypothesis that Rgg proteins participate in the fine and complex regulation of S. thermophilus gene expression
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Liu, Liyuan. "Les matériaux 2D pour le stockage de l'énergie." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30204.
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L'objectif de cette thèse est d'étudier les propriétés électrochimiques des matériaux 2D utilisés comme électrode dans les batteries et les supercondensateurs. La première partie commence par la synthèse du graphène et la préparation des films d'électrode. Une étude détaillée des propriétés électrochimiques du stockage des ions potassium a été réalisée en utilisant un aérogel à oxyde de graphène réduit (rGO) comme matériau d'électrode négative. L'influence de la nature de l'électrolyte et les méthodes de séchage utilisées ont été étudiées afin d'optimiser les performances électrochimiques du rGO lyophilisé dans les batteries potassium-ion (PIB). La spectroscopie d'impédance électrochimique (EIS) a été utilisée pour évaluer les performances de notre matériau rGO dans les PIB. Utilisé comme électrode négative, le rGO lyophilisé peut fournir une capacité élevée de 267 mAh g-1 à un taux de C/3 avec une rétention de capacité de 78% pendant 100 cycles, combinée à une capacité de taux élevé (92 mAh g-1 à 6.7 C ). Cet ensemble de résultats rend de l'aérogel rGO un matériau d'électrode prometteur pour les PIB. Ensuite, nous nous sommes concentrés sur la méthode du sel fondu (MSM) pour concevoir des matériaux aux propriétés électrochimiques améliorées pour les applications de stockage d'énergie. Avec le MSM, une quantité considérable d'oxydes ternaires Mn-based 2D and V-based 1D a été explorée puis utilisée comme cathode pour les batteries divalentes aqueuses. La nanoparticule K0.27MnO2·0.54H2O (KMO) a été utilisée comme cathode pour les batteries aqueuses Zn-ion, avec des capacités spécifiques élevées (288 mAh g-1) et une cyclabilité à long terme (rétention de capacité de 91% après 1000 cycles à 10 C) . La technique Electrochemical quartz crystal admittance (EQCM) a d'abord été réalisée pour confirmer le mécanisme de stockage de charge d'intercalation H3O+ et Zn2+ qui en résulte. De plus, le procédé au sel fondu utilisé ici a permis la préparation de 1D CaV6O16·7H2O (CVO) et utilisé en outre comme matériau de cathode dans des batteries aqueuses au Ca-ion. En conséquence, d'excellentes performances électrochimiques ont été obtenues, avec une capacité de 205 mAh g-1, une longue durée de vie (> 97% de rétention de capacité après 200 cycles à 3C) et des performances élevées (117 mAh g-1 à 12 C ) lors de réactions d'intercalation (de) intercalation des Ca-ions. Contrairement à la précédente méthode de sel fondu flash réalisée dans l'air, nous avons conçu une autre méthode de sel fondu sous atmosphère d'argon pour préparer des matériaux de carbures métalliques 2-dimmensionnels (MXene) tels que Ti3C2 (M = Ti, X = C). En jouant avec la chimie du précurseur MAX et la composition de la fonte acide de Lewis, nous généralisons cette voie de synthèse à une large gamme chimique de précurseurs MAX (A = Zn, Al, Si, Ga). Les matériaux MXene obtenus (appelés MS-MXenes) présentent des performances électrochimiques améliorées dans un électrolyte non aqueux contenant du Li+, avec une capacité de 205 mAh g-1 à 1.1 C, ce qui rend ces matériaux très prometteurs en tant qu'électrodes négatives pour les batteries Li haute puissance ou les appareils hybrides tels que les condensateurs Li-ion. Outre l'APS, un autre agent de gravure (FeCl3) a été utilisé pour dissoudre le Cu. En résumé, cette méthode permet de produire de nouveaux types de MXène difficiles voire impossibles à préparer en utilisant des méthodes de synthèse précédemment rapportées comme la gravure HF. En conséquence, il élargit encore la gamme de précurseurs de phase MAX qui peuvent être utilisés et offre des opportunités importantes pour ajuster la chimie de surface et faire du MS-MXene une électrode à haut débit dans un système non aqueuxThe aim of this thesis is to study the electrochemical properties of 2D materials used as electrode in batteries and supercapacitor. The first part starts with using reduced graphene oxide (rGO) aerogel as a negative electrode material for potassium-ion batteries (PIBs). The influence of the nature of the electrolyte and the drying methods used were investigated in order to optimize the electrochemical performance of freeze-dried rGO in PIBs. Electrochemical impedance spectroscopy (EIS) were used to assess the performance of our rGO material in PIBs. rGO can deliver a high capacity of 267 mAh g-1 at C/3 rate together with 78% capacity retention during 100 cycles, combined with high rate capability (92 mAh g-1 at 6.7 C). This set of results makes rGO aerogel a promising electrode material for PIBs. Afterwards, we focused on molten salt method (MSM) to design materials with enhanced electrochemical properties for energy storage applications. With MSM, 2D K0.27MnO2·0.54H2O (KMO) and 1D CaV6O16·7H2O (CVO) have successfully prepared. KMO nanosheet has been used as cathode for aqueous Zn-ion batteries, with high specific capacities (288 mAh g-1) and long-term cyclability (91% capacity retention after 1000 cycles at 10 C). Electrochemical quartz crystal admittance (EQCM) technique was firstly performed to confirm the consequent H3O+ and Zn2+ intercalation charge storage mechanism. Additionally, CVO was further used as cathode material in aqueous Ca-ion batteries. As a result, excellent electrochemical performance was achieved, with a capacity of 205 mA h g-1, long cycle life (>97% capacity retention after 200 cycles at 3C rate) and high rate performance (117 mAh g-1 at 12 C) during Ca-ion (de)intercalation reactions. Differently from the previous flash molten salt method achieved in air, we designed another molten salt method under argon atmosphere to prepare 2D metal carbides (MXene) materials such as Ti3C2 (M=Ti, X=C). By playing with the chemistry of the MAX precursor and the Lewis acid melt composition, we generalize this synthesis route to a wide chemical range of MAX precursors (A=Zn, Al, Si, Ga). The obtained MXene materials (termed as MS-MXenes) exhibits enhanced electrochemical performance in Li+ containing non-aqueous electrolyte, with a capacity of 205 mAh g-1 at 1.1 C, making these materials highly promising as negative electrodes for high power Li batteries or hybrid devices such as Li-ion capacitors. Besides APS, another etchant (FeCl3) has been used to dissolve Cu. Furthermore, high conductive ACN-based electrolyte has been applied to improve the power performance of multi-layered MS-MXene. To sum up, this method allows producing new types of MXene that are difficult or even impossible to be prepared by using previously reported synthesis methods like HF etching. As a result, it expands further the range of MAX phase precursors that can be used and offer important opportunities for tuning the surface chemistry and make MS-MXene as high rate electrode in non-aqueous system
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Tsai, Yo-Hunmg, and 蔡友煌. "Color Control of RGB LED." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/58422936347529243592.
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碩士明志科技大學
機電工程研究所
98
This thesis presents the color mixing of red, green and blue light emitting diodes (LED).In order to verify the adopted additive color mixing,a MCU-based RGB-LED lamp,which uses an 8-bit microcontroller, HOLTEK 46R24,is built and a miniature fiber optic spectrometer, USB 4000, and accompanied Spectra Suite software produced by Ocean Optics Inc. are used to measure the experimental results. Based on the temperature characteristics of the used red, green and blue LEDs,color deviations arisen from temperature variations are successfully compensated.
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Lin, Hong-Shen, and 林宏森. "RGB LED backlighting optical feedback compensation." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/15251730552257817348.
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Bautista, Meriam Gay, and 梅利安. "Dimmable Multi-Channel RGB LED Driver." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/41938135831591875664.
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碩士國立臺北大學
電機工程學系
101
This paper proposes a dimmable multi-channel Red-Green-Blue (RGB) LED Driver for backlighting and display and applies variable control technique to regulate color mixing. A linear Control DC-DC converter is used to provide the needed constant current for the RGB LEDs. It is designed to provide greater than 25mA constant output current with high accuracy. A PWM control method is used, of which the variable external voltage determines the available brightness levels and has a dimming frequency of 2 kHz. The proposed LED driver system is also able to dim each individual LED color through the dimming controller circuit; for each of the 3 channel per color around 90%, 93% 93% efficiencies for the red, green and blue channels respectively. A digital port was provided for the option of Digital dimming using a microcontroller. A linear current regulator is presented and this can be extended and applied to multiple strings. The temperature coefficient for the red channel is 75.43 ppm/°C and 89.46 ppm/°C for both green and blue channel. This was designed and simulated using 0.35micron TSMC 2P4M 5V technology and the chip area is 2.31x1.48 (mm2).
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Lai, Shih-Tao, and 賴世道. "Implementation of RGB Mixed LED Backlight Circuit." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/61022110861728633701.
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碩士中原大學
電機工程研究所
95
Abstract Conventionally, multiple cold cathode fluorescent lamps (CCFLs) are required to provide sufficient backlighting for a large-scale of LCD panels. Growing concerns about environmental issues will exhibit the use of CCFLs that contain poisonous mercury. Owing to improvement in long operative life, wider operation temperature range, and the simplicity of driver circuit: work with low and safe voltages, LED has gradually substituted for CCFL as backlight. In this thesis, a LED backlight circuit for a large-scale LCD panel is studied. The design considerations for RGB LED backlighting circuit are discussed in detail. Burst-mode dimming control is designed to achieve the brightness regulation of the backlighting LEDs. A laboratory prototype for the studied RGB LED backlight circuit is implemented and tested. The experimental results of the prototype circuit are shown and discussed to verify the proposed scheme.
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Lin, Yu-Te, and 林育德. "AC/DC integrated RGB LED backlight driver." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/60298945731246619418.
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碩士雲林科技大學
電機工程系碩士班
97
A RGB LED backlight driven by a integrated converter is proposed in the thesis instead of CCFL as a Lcd backlight. A flyback converter with three windings takes place of conventional three DC/DC converter so as to improve the efficiency and to decrease the cost. Series-parallel LEDs is controlled by several constant-current circuits and the brightness modulation can be much find and smooth by adjusting PWM signal. The operation principle, analysis and design of the converter more detail. Experimental results show a prototype for Vin=85~265VAC, 40W, operating at switching frequency of 65KHz to verify the performance of the proposed converter.
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Wang, Guan-Ren, and 王冠仁. "Characteristic Analysis of High Power RGB-LED." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/96160436535201757150.
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碩士和春技術學院
電機工程研究所
95
The operating characteristics of high power RGB-LED are investigated in the thesis, including the effects of the driving current type, something characteristics about electrical and optical, ambient temperature, and used-time. Before conducting experiment, this thesis is aimed at the process of measure, in order to ensure the experimental accuracy, it would obtain the needful procedure of experiment. To observe the RGB-LED characteristics of optical and electrical, this thesis focus on 1W RGB-LED to use the driving way of constant currents and pulse wave currents when control every 50mA interval from 100mA to 350mA and every 10oC interval from ambient temperature 10oC to 70oC. Additionally, in order to observe the RGB-LED characteristics in long used-time, we would deposit the RGB-LED in a chamber and operate at the constant current 350mA, then it would light up long time with the temperature at 40oC, 50oC, 60oC, 70oC, individually, and which is measured every 500 hours. This associated experiment more realize the characteristics of RGB-LED, it would provide the future with foundation of the LED driving cogitation.
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Shiue, Shy-Haw, and 薛世浩. "RGB LED Color Modulation Driving Circuits Design." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/29606632168875145248.
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碩士華梵大學
機電工程學系博碩專班
98
This thesis presents a digital dimming control circuit for RGB LEDs including driver. We simulate the function of RGB colors using FPGA first, then layout the circuit structure by “TSMC 0.35um MIXED MODE (2P4M, 3.3V/5V) process”. Finally, we can achieve the integrated circuit. The digital circuit is simulated by Xilinx Spartan XCS20XL which is 17 bits dimming. We use a method “pulse width modulation (PWM)” to achieve the RGB mixing light. We simulate the analog circuit with Hspice, layout with Laker made by Springsoft Inc., and verify with Calibre DRC（Design Rule Check）、LVS（Layout vs Schematic）、PEX（Post layout extraction）made by Mentor Graphics Corp. The life of light emitting diode will be decreased with rising temperatures it used by a long time. When we make a module for a LED application, the temperature will rise more easily. Besides packages and cooler, we also have to consider whether if the qualities and functions will be changed by the varieties of the temperature. Therefore, we use “Application-Specific Integrated Circuit” to achieve a high speed, stable, and low cost integrated circuit. Keywords：RGB LED、FPGA、PWM、ASIC
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Yang, Zong-Zhen, and 楊宗振. "Study on RGB LED Backlight Driving System." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/79908509970872481866.
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博士國立臺灣科技大學
電機工程系
100
In this dissertation, a digitally-controlled LLC resonant converter for RGB LED backlight driving system is proposed. The LLC resonant topology allows for zero voltage switching (ZVS) of the main switches thereby dramatically lowering switching losses and boosting efficiency. Field color sequential techniques, local dimming control and dynamic bus voltage regulation technologies are then implemented in the proposed system. Using the topology proposed in this dissertation, only one power converter is required to drive the red, green and blue LED strings; therefore the system configuration is very simple. By dividing the backlight into four areas, the backlight brightness of each area can be individually controlled. The output voltage is adjusted by the proposed digital controller so that RGB LED maintains the desired string current. Because the voltage across the linear current regulators in the system is the minimum voltage, the driving system efficiency is maximized. The proposed backlight driving system boasts the advantages of simple circuit structure, improved power efficiency, high contrast ratio and wide color gamut. Finally, experimental results are presented to validate the effectiveness and correctness of the proposed system. According to the experimental results, the presented system can successfully drive the RGB LED backlight module, and the color-mixing, local dimming and bus voltage regulation functions can be achieved.
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Hou, Chih Teng, and 侯智騰. "Liquid Encapsulated RGB-Stack LED Power Module." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/78146842521719835462.
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Wu, Zong-hua, and 吳宗樺. "An RGB-LED Back-Light Driving Circuit." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/4829ez.
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碩士國立中山大學
電機工程學系研究所
95
This thesis proposes a novel driving circuit of the RGB light emitting diodes (LEDs) for the back-light source of the liquid crystal display. In stead of employing three dc-to-dc converters, a fly-back converter with three secondary windings is used to drive RGB-LED light bars. By adjusting the duty-ratio, the fly-back converter provides compromised voltages to RGB-LEDs in accordance with the operating modes of dimming control, so as to retain current magnitudes within the acceptable values. LEDs of three colors are dimmed by regulating the duty-ratios of three active power switches individually. By changing the ratio of the average currents of the three primary color LEDs, the color temperature range of driving can reach the requests of dimming control. As compared with a consumer product using the conventional driving circuit, the proposed circuit is obviously much simpler with less components and a higher efficiency.
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Ming-HungPan and 潘明宏. "Chromatic Detection for RGB LED Back Lighting Unit." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/25653303261318200411.
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碩士國立成功大學
工程科學系專班
98
The RGB LED light source not only performs high purity monochromatic light and low power consumption, but also conforms to the environmental protection rule of Restriction of Hazardous Substance. It is one of the major developing techniques for flat panel display industries. This thesis utilized different detection methods to detect the chromaticity variation of RGB LED back lighting units, and then analyzed the advantages and disadvantages of them. These methods primarily involved color-meters, portable spectrometers, and normal color digital cameras as basic frameworks for detection. In addition, the linear light source LED light-bars used in back lighting units were used to exhibit the RGB’s three primary colors and six mixed-color modes through different circuit driver methods. We divided the back lighting unit display area into a 3x3 matrix with nine points for chromatic measurement. The color-meter used in this study directly measured the chromaticity at nine points by single-point movement, which was different from the spectral power distributions measured by the spectrometer. The digital camera obtained image information from the complete display area, then extracted the color map distribution data from nine points at once. Finally, the CIE1931 color system and Matlab programs were used to calculate chromaticity. Using data from RGB LED back lighting unit, this study found that the chromatic detection capacities of the three detection methods- evaluated by NTSC standards, were: color-meter 139.86%, spectrometer 108.42%, and color digital camera 70.69%. By using data from the six mixed-light mode, we can determine the sensitivity based on the largest variance detected by the three detection methods facing minimal color changes, the detection methods were ranked in order as: spectrometer 0.065%, color-meter 0.047%, color digital camera 0.014%. Chromaticity and color temperature data were used to confirm that the color digital camera possessed the detection trends of color-meters and spectrometers, which were useful for RGB LED back lighting unit detection, capturing images via the Matlab program, processing multiple points of color data at once, and obtaining chromaticity values more quickly than the single-point movement method.
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Wu, Guo-Yang, and 吳國揚. "Analysis of LED Array of RGB LEDs by Artificial Neural Network." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/12968455321632161681.
Full textAbstract:
碩士國立雲林科技大學
電子與光電工程研究所碩士班
100
High power light-emitting diodes (HP-LEDs) always are applied for energy-saving to replace the traditional light sources. Therefore, the high power LED lighting has been regarded in the next generation lighting. In this study, we design the LED array of 2 × 3 with the best artificial neural network (ANN) training model to find the optimization of the neural network calculus. Then, one array data of experimental result was used as the basic to forecast the chromaticity coordinate values of the other 16 arrays. The chromaticity coordinates of the 17 groups LED array were measured by the integrating sphere based on the color temperature of D65. The coordinates of the chromaticity would be simulated and discussed by the optical simulation software and the Artificial Neural Network with optimization algorithms. It was the smallest average error than all with the neural algorithm of Levenberg-Marquardt (L.M.) model. Using the L.M. model to train the model and get the error percentage for the 16 arrays to compare on the basic array. Anyway, the least and highest error rate are 0.2272% and 2.028% for 14th array, respectively. The simulation results with neural network training are 1.027% better than 2.141% that of Trace-Pro simulation. 94.12% arrays could reach the standard with the error rate under 2%, but only 35.29% arrays could reach the standard with the error rate under 1%.
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Hung, Chien-Chung, and 洪健忠. "High Power RGB-LED Model and its Circuit Applications." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/12189294601121264832.
Full textAbstract:
碩士和春技術學院
電機工程研究所
96
The purpose of this thesis is to investigate the optical and electrical characteristics of high power LEDs under different current and ambient temperature. At the same time, Is Spice software is used to build its model and modulize it. In this thesis, integrating sphere system is used to measure the variation of characteristics of 1W RGB-LED, such as luminous flux, dominant wavelength and equivalent resistance, etc., at the driving current from 100mA to 350mA and ambient temperature controlled at 10oC to 70oC. Based on experimental data, a model is built for further verification by practical circuit application after the establishment of such module. The performance of this modulized model is found more accurate through comparison between simulation result and experimental data using a lighting circuit design composed of 5 pieces of 1 W-LED. This finding could provide a reference for future design aiming at high power LED driving circuit to reduce development and design cost.
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Hsieh, Mingyu, and 謝明諭. "Mini/Micro LED Display Module with RGB Full Colorization." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/g874bd.
Full textAbstract:
碩士逢甲大學
自動控制工程學系
107
Mini/Micro-LED display is considered as the most promising one among the products of display technology for next generation. The major advantages are high efficiency, high brightness, high reliability, fast response, and low power consumption. However, it suffers from several limitations, such as mass transfer technology, full colorization, and driver IC. In view of this, this research proposes a Mini/Micro-LED display module with RGB full colorization. The core concept is to produce a white light through integrating the blue LED array and the yellow phosphor film. Furthermore, the color filter was combined to achieve a self-emitting full-color display with RGB dot array. The display module was mainly divided into three parts, including the LED array, electroformed nickel with holes’ structure, and color filter. First of all, the 32×32 LED arrays with the pixel size 200×200 μm2, 100×100 μm2, and 80×80 μm2 are fabricated, simultaneously. After that, the holes and filter fabrication are finished by nickel electroforming and photolithography process. Finally, the three parts of entire display module was integrated by vertical stacking. Based on the above methods, the experimental results show that R, G, and B three color lights are produced, effectively, and the corresponding peak wavelength are 590 nm, 540 nm, 465 nm, respectively. However, the module is limited by the sapphire thickness and the Lambertian light distribution result in the brightness and contrast decreased. In the future, the problems mentioned above can be solved by optimizing the structure design.
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Hung, Chung-Chih, and 洪崇智. "Auto Mixed Light Research for RGB LED Backlight Module." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/26t9k7.
Full textAbstract:
碩士國立虎尾科技大學
電機工程研究所
96
In this thesis, light emitting diodes with red, green, and blue lights, respectively, are served as the back-light source and employed to generate the three primitive colors that can be adjusted and mixed to realize the output of white light. Attempts to bring out wider range of color space and obtain higher color saturation can, thus, be achieved. With the introduction of a half-bridge converter with power factor correcting function, an isolated-power-driven light-emitting diode is developed. By using the light-mixing and adjustment technique, the power saving and white light stabilizing can be accomplished. Through the experimental observations and quantitative measurements, the features of light-emitting diodes and photo-detectors are found to be susceptible to temperature. Moreover, different photo-detectors experience different degree of change of features for temperature fluctuation. To prevent the output white light from being experienced with color deviation due to temperature effect on the performance of LED, a mixed-light circuit module is developed, by integrating Programmable System on Chip with photo-diode sensor devices, to examine the ambient temperature and feedback voltage level of RGB photo-diodes. Through the usage of mixed-light control circuit module, the corresponding duty cycle of RGB LED can be adjusted, and the stable white light output can, consequently, be achieved. Furthermore, attempts to correct the error produced by photo-detector diode due to temperature are made by the introduction of a temperature sensor. A so-called “Mixed-light and adjustment control module corrector” was implemented to correct temperature modified value. By mixed-light and adjustment control module and calibrating of the corrector, the CIE1931 xy coordinates of output light are in good agreement with the predicted results.
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Kun-YuanLee and 李坤原. "Real-time Chromatic Control for RGB LED Back Lighting Unit." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/78185511581632702011.
Full textAbstract:
碩士國立成功大學
工程科學系專班
98
The brightness and wavelength of LED will be shifted by temperature change. The brightness shift can be compensated by the duty cycle in pulse width modulation (PWM). But the wavelength shift was not compensated in general. Due to the different driving current of LED has different radiate wavelength, we attempt to modulate the driving current of LED into a control system in this thesis. So, as the temperature increasing, the system can immediately adjust the duty cycle and the driving current to keep the color temperature stable. The objective of this thesis is to utilize the duty cycle modulation to keep brightness stable and change the driving current of LED with temperature to reduce wavelength shift. Based on the described real time feedback and modulation, we can keep the color temperature of back lighting unit around 5500K. The maximum change of color temperature is less then 64K when the temperature is from 25 to 45℃; the maximum distance of CIE1976 chromaticity diagram in u^' and v^' axis at change from 0.0111 and 0.0067 to -0.0017 and 0.0020. The average color difference of back lighting unit ?u^' v^', which is the directly distance at chromaticity diagram, change from 0.0115 to 0.0008.
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Huang, Ming-Wei, and 黃明偉. "The Design of Digital Control System for RGB-LED Backlighting." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/5287w2.
Full textAbstract:
碩士中原大學
電機工程研究所
98
The objective of this thesis is to design a Digital Control System for RGB-LED backlighting. This study is mainly comprised of software development environment planning, hardware design, and verification of the system functions. The design tools employed for the software include SOC with 8052 MCU, Source-Insight, Keil C, and an ISP Board. The design of hardware involves an RGB-LED array and an RGB-LED driving circuit, in which the electrical design is derived from the requisite specifications whilst involving a designed integrated layout. The control function of the system is produced by SOC with 8052 MCU to produce visible light with full-coloring. Finally, the Digital Control System for the RGB-LED backlighting was verified via the development of an automatic cycling function for the RGB-LED backlighting.
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Lin, Chung-Yi, and 林忠毅. "Study of RGB LED Color Mixing Mechanism for Oral Illumination." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/9pq6cx.
Full textAbstract:
碩士國立中正大學
光機電整合工程研究所
103
This paper studies the detection of oral illumination flashlight lighting, through a flashlight inside the mirror architecture designed to perform the RGB LED color mixing lighting, from past studies typically use color mixing light pipe diffusion sheet and a plurality of optical components such as lenses to complete the color mixing, so we hopes to use the self-developed optical design of stretched the distance mixed light reflective color mixing lighting. By Solidworks modeling and ASAP ray tracing simulation scenarios, lighting placed in front of each one face, face to use for analysis ,project analysis, including illumination, illumination uniformity, color mixed effects. According to the simulation results can be designed to understand the method of the reflecting surface can be simplified and a more uniform illumination, it can achieve the purpose of saving costs, the mixed light lighting can change its color mixing through modulation of the LED luminous intensity in different lighting, so in the future will be for oral illumination medically helpful.
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Sun, Chong-Yuan, and 孫仲元. "Design and Implementation of FPGA-Based RGB LED Dimming Control." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/83203803971251307583.
Full textAbstract:
碩士南台科技大學
電機工程系
96
This thesis presents the implement and design of FPGA based RGB LED backlight digital control, including dimming control, feedback control and RS-232 baseband control. By using the digital PWM duty cycle to dim the illumination, we can achieve the RGB mixing light source with unique features such as instant color variability, and proposing three kind of RGB LED dimming control circuit. Under the long time use of LED, its part can affect brightness and stability of the color temperature along with the temperature change. The proposed article makes optics feedback on using the photo sensor element, fuzzy controller stabilizing the color of RGB LED backlight color drift phenomenon which under a long usage, produces the feedback voltage of photo sensor element. Finally, through the experiment, it can be demonstrated that the open loop controls RGB LED the color, and closed loop control stabilizes the RGB LED color temperature.
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Lai, Peng-Yu, and 賴鵬宇. "Investigation of Discomfort Glare of RGB LED Billboard at Night." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/55783798744566716363.
Full textAbstract:
碩士國立臺灣科技大學
色彩與照明科技研究所
101
Mesopic vision is gaining high attention from lighting researchers and industry people re¬cently. Most night-time outdoor and traffic lighting scenarios are belong the mesopic range. As known as the Purkinje effect, the peak of spectral luminous efficiency shifts to the short-wavelength range in mesopic region. Full color RGB LEDs, which are becoming a popular and energy efficient source for dynamic lighting and displaying information, generally have more wide color gamut than conventional lamps for outdoor lighting like high pressure sodium (HPS) lamps. In addition, achromatic and chromatic color stimuli with same luminance are generally different in brightness (or perceived lightness). The brightness of the latter is higher than the former. The phenomena are well-know and identified with the Helmoholz-Kohlrausch effect (H-K effect). Those imply that LEDs have a potential risk over conventional lamps in terms of discomfort glare. In the measurement, we have 108 different kinds of conditions using the full-color LED billboard with nine color photographs, three color gamut, two kinds of background luminance and two groups of ages. Results revealed that there are significant main factor effects of age, saturation, image and gender in twenty subjects for de Boer glare rating scale. There are three significant interaction effects, including age and saturation, age and image, image and gender. Furthermore, we found that different saturation of displayed images will affect glare discomfort score. Post hoc tests indicated that wide-gamut of RGB LED billboard demonstrated the highest de Boer rating scores (Mean100LED = 4.64; Mean069LED = 4.25; Mean033LED = 3.99), with statistically significant differences detected among three gamut settings. For different age groups, the effect of age was significant. The luminance of the background is not significant. This paper presents results from an ongoing study that compares discomfort glare for different color gamut of RGB LED billboard using the de Boer rating scale. The subjective results were also compared with previous discomfort glare equations. Final, the discomfort glare of RGB LED billboard were described to develop a new discomfort glare equation for outdoor at night.
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Huang, Chien-shun, and 黃建順. "Development of Wireless RGB LED Dimming Control Technology Using Tablet." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/50454950974127890772.
Full textAbstract:
碩士國立臺灣科技大學
電機工程系
101
High intensity light emitting diodes (LEDs) are available in an ever-increasing number of general lighting products. In addition to advantages such as higher energy efficiency and longer life, LED lighting also boasts advantages including low profile, compact size, cold temperature operation, fast turn on time and full controllability. For LED lighting applications, lighting control includes dimming and color control offer potential for increased energy efficiency and user satisfaction. On the other hand, tablets are gaining their popularity due to their portability and their ease of use. The tablet users can use a touchscreen to react to what is displayed and to control how it is displayed; therefore is a suitable candidate for home automation. Of all the user interfaces for home automation, touch screens are the most intuitive and easiest to use. In this thesis, a LED lighting control system based on the Bluetooth wireless network is proposed. The presented system includes three RGB LED light bars and one white LED light bar, a lighting control app for tablets and a Bluetooth communication module for remote control. The hardware and software design will be presented in detail. The experimental results show that tablet is a good candidate for home lighting control applications. Moreover, tablet apps enable easy connection; therefore offers advantages include product interoperability, vendor independence, and accessibility to broader markets.
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Lee, Shih Lung, and 李仕龍. "Light Output Feedback Control System Design for RGB LED Color Stabilization." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/73922408309821893044.
Full textAbstract:
碩士國立交通大學
顯示科技研究所
96
LCD (Liquid Crystal Display) is the mainstream product to replace CRT (Cathode Ray Tube). Conventionally, CCFL (Cold Cathode Fluorescent Lamp) is used as a light source of LCD backlight. However, LED (Light Emitting Diode) is regarded as the candidate to replace CCFL (Cold Cathode Fluorescent Lamp) as light source of LCD backlight due to its wide color gamut, low operation voltage, mercuryfree characteristic, and fast switch response. The color shift due to heat effect after long time usage is an issue needed to resolve. In this thesis, a 14 bits recursive feedback control system is proposed and realized to stabilize the light output of RGB (red, green, and blue) LEDs by generating tiny recursive current in μA order. Whereas the just noticeable color difference (Δu’v’) of human is 0.005, feedback control system is proved that color difference (Δu’v’) of Red, Green, and Blue LEDs are kept within 0.005 under 13 bits resolution, and within 0.004 under 14 bits under aging simulation of 3250, 3969, and 4462 hours usage, respectively.
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陳君瑜. "Silicon-Based LED Packaging Module with an Integrated RGB Color Sensor." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/10440531911946082646.
Full textAbstract:
碩士逢甲大學
自動控制工程學系
102
Thermal management is an important issue for LED packaging. In particular, high power LEDs are subject to high temperatures, which reduce the brightness and alter the color temperature, so external physical sensing devices, such as temperature and photo sensors, and heat dissipation apparatus with control circuits are necessary, to modulate the operating temperature. However, these additions increase packaging volume, integral complexity and cost. To address the above problems, a silicon-based LED packaging module with an integrated RGB color sensor is proposed in this study. The design concept uses MEMS process and monolithic integration technology to fabricate photo sensor with RGB color photoresist on a silicon wafer for the modular packaging with LED. The RGB photo sensors used to detect the brightness and intensity of light source in specified wavelengths, and therefore the optical characterization in this packaging level can be identified for real time control. In which, the photosensitive element and LED carrier structure are directly fabricated on a silicon wafer, using ion doping, color photoresist spin coating and inductively coupled plasma etching, thereby achieving a smart LED packaging module featuring miniaturization, integration and low cost. This method reduces the cost and promotes its applications due to the system in packaging (SIP) at a wafer level. The dimensions of single module were 1×1 cm2; the light source is a 1-watt blue ray LED encapsulated yellow phosphor. Based on above measurement result, the brightness, chromaticity and color temperature of the LED packaging module can be identified during operation process.