Este trabalho se encontra dividido em duas partes. Em uma parte inicial, relatamos a construção e caracterização de um laser de centro de cor (LCC) com meio ativo de KCl:Li+, operando de forma sintonizável no infravermelho na região em torno de 2,7 um. São descritas três configurações distintas para a cavidade do laser, e fazemos um estudo comparativo do desempenho do LCC para os três casos. Na segunda parte, o laser de centro de cor foi transformado em um espectrofotômetro de duplo feixe de alta resolução (largura de linha OMEGA-V<O,2 cm-1), com o qual passamos a estudar amostras cristalinas de NaF multiplamente dopadas com impurezas moleculares OH- e monoatômicas Cu+. Relatamos novas características desse material, que surgem em virtude da interação entre as referidas impurezas. Dentre essas características, temos o surgimento de um espectro complexo de linhas deslocadas para menores energias com relação a banda de absorção do modo de estiramento do OH-. Parâmetros de anarmonicidade são analisados, os quais sugerem a existência de anarmonicidade elétrica em adição a anarmonicidade mecânica. Estudos da dependência das larguras das bandas de absorção com a temperatura juntamente com medidas de TSDC ( corrente de despolarização termo-estimulada), revelaram a existência de um comportamento diferente daquele de rotor quase livre encontrado para o OH- em vários halogenetos alcalinos. Os resultados mostraram que no cristal de NaF tanto o OH- isolado quanto o acoplado estão permanentemente orientados / This work has two parts. The starting one is related with the construction and characterization of a tunable color center laser (CCL) with an active medium of KCl:Li+ which works in the mid infrared region around 2,7 um. It is discussed three different configurations set up for the laser cavity, and the profile of each case is compared between each other. For the second part, the color center laser is used as the source of a high-resolution double beam spectrophotometer (line width OMEGA-V<O,2 cm-1). The spectrophotometer is used to study multiple doped NaF crystal samples, with OH- molecules and monoatomic Cu+ impurities. New optical properties are found due to assumed coupling interaction between both impurities, which gives rise to a more complex spectrum where several lines are displaced to lower energies relative to the main OH- stretching mode absorption. Some anharmonic effects are observed, which suggests the existence of electric anharmonicity added to the mechanical one. Further study of the bandwidth temperature dependence, together with thermally stimulated depolarization current measurements, reveal a different behavior of the usual OH- quasi-free rotor found in several alkali halides. The results show that for the NaF crystal the isolated and coupled OH- ions are permanently oriented

FM halftoning is increasingly popular with traditional analog offset lithographic printing processes. There is a desire to offer this capability with digital presses based on electrophotographic printing (EP) technologies. However, the inherent instability of the EP process challenges the achievement of satisfactory print quality with dispersed-dot, aperiodic halftoning. The direct binary search (DBS) algorithm is widely considered to represent the gold standard of dispersed-dot, aperiodic halftone image quality. In this paper, we continue our previous efforts to adapt DBS to use with the Indigo liquid EP printing technology. We describe a complete color management pipeline for halftoning with a PARAWACS matrix designed using DBS. For the first time, we show actual printed patches obtained using our process. Our gamut mapping is performed in the YyCxCz color space, and is image-dependent. It incorporates several stages of alignment between the input and output spaces, as well as several stages of compression. After the gamut mapping, we tessellate the output color space into six global tetrahedra that each share the neutral axis, as an edge. Then, we determine the Neugebauer Primary Area Coverage (NPAC) for each pixel in the image to be printed by tetrahedral interpolation from the four nearest neighbors in the inverse printer mapping table. These four nearest neighbors are chosen so that only four Neugebauer primaries are used to render each pixel.

Para compreender a relação entre cor e fotografia, investiguei seus aspectos técnicos e poéticos. Aprofundando-me na pesquisa de importantes fotógrafos que trabalham com a cor, realizando uma série de entrevistas com os artistas estudados e especialistas na área e construindo uma prática artística pessoal, procuro mostrar nesta dissertação como a cor adquire autonomia, tornando-se elemento estrutural da obra. / To understand the relationship between color and photography, I investigated the technical and poetical aspects. Deepening in the researches about important photographers that work with color, making a series of interviews with the artists that had been studied and professionals from the area and building an artistic personal practice, I try to show in this dissertation how the color acquires autonomy becoming a structural element of the work.

O trabalho consiste na análise do processo de construção do sentido, a significação, na linguagem musical do compositor Hermeto Paschoal, por meio da Teoria Semiótica de linha francesa fundada por A. J. Greimas. Estudar a música instrumental, através da abordagem semiótica greimasiana, coloca-nos diante de uma série de questões teóricas, relativas à possibilidade de um sentido definido no plano de expressão, bem como à própria definição de sentido que procuramos desenvolver. Segundo a orientação que tomamos, procuramos verificar as possibilidades e os limites da teoria semiótica quando aplicada às linguagens abstratas, no nosso caso, a linguagem musical. Além dos problemas teóricos, encontramo-nos diante do desafio de investigar a intrigante música de Hermeto Paschoal que, se por um lado é realmente complexa, por outro, a capacidade do compositor transformar em música qualquer dado sonoro e criar incessantemente sobre todos os parâmetros do som, como altura, duração, intensidade e timbre, faz de sua obra um objeto muito rico para o trabalho que pretendemos desenvolver. Mais que isso, Hermeto vale ser estudado pela sua importância na cultura brasileira e no cenário da música internacional, tanto quanto pelo grande valor estético de sua arte. Embora nossa proposta seja a de investigar os problemas relativos ao plano da expressão e estudar a Teoria Semiótica aplicada linguagem musical, orientamo-nos, mais simplesmente, pela curiosidade de compreender o que ?diz? a música de Hermeto Paschoal, e pela convicção de que as sonoridades da música instrumental fazem sentido / This study analyzed the construction process of meaning of the musical language of Hermeto Paschoal\'s instrumental music using the A.J. Greimas\' semiotics theory. The evaluation of instrumental music using Greima\'s semiotic approach raises many theorical questions regarding the possibility of a defined meaning on the plan of expression, as well as the definition of meaning by itself, which we tried to develop. According to direction that we followed, we tried to verify the possibilities and limits when the Semiotic Theory is applied to abstract languages, such as the musical language. Besides the theoric issues, we faced the challenge of investigating the intriguing Hermeto Paschoal\'s music, which may be considerably complex, but on the other hand is an extremely rich object to be evaluated considering the composer\'s ability to convert to music any sound, and to incessantly create music varying all parameters such as volume duration, intensity and timbre. Furthermore, the study of Hermeto Paschoal\'s music is valuable not only because of the esthetic quality, but also due to its remarkable importance for the Brazilian culture and the International musical scenario. Although our aim is to investigate the issues related to the expression field and to study the Semiotic Theory applied to the musical language, we more simply attempted to focus and comprehend the meaning of Hermeto Paschoal\'s music and confirm the evidence that the sounds created on the instrumental music have a meaning

Através do fato de que os silicones pigmentados utilizados na confecção de aloplastias para a reabilitação de pacientes portadores de defeitos faciais apresentam alteração cromática com o decorrer do tempo na experiência clínica, e pela escassez na literatura específica de trabalhos experimentais relacionados ao tema, principalmente quanto aos silicones industriais de cura acética, o presente trabalho tem como objetivo verificar o comportamento de três tipos de silicones diferentes coloridos com um determinado pigmento (pó para maquiagem facial), usados rotineiramente no atendimento de próteses faciais. Os silicones usados foram um de cura por calor (HTV) para finalidades médicas, um de cura acética (RTV) para fins industriais com especificações de normas alimentícias e outro também de cura acética (RTV), porém somente de normas industriais. Para a realização do experimento confeccionou-se 30 corpos de prova, sendo 10 para cada tipo de silicone, que foram analisados por espectrofotômetro. Após análise, cada grupo foi dividido em 2 subgrupos, de 5 unidades cada, um grupo exposto (E) e um grupo controle (C). Os 3 grupos (E) passaram por envelhecimento acelerado em exposição ambiental, enquanto os 3 grupos (C) ficaram acondicionados em um lugar totalmente escuro em temperatura ambiente. A leitura inicial foi considerada padrão, enquanto as seguintes foram aos 45 e 90 dias. Os dados obtidos nas três medições foram usados para avaliação das alterações cromáticas. Com os resultados estatísticos após análise, concluímos que todos os silicones expostos apresentaram alteração na cor clinicamente inaceitável, sendo que nos grupos controle somente o silicone de cura acética (RTV), industrial com especificações de normas alimentícias, apresentou mudanças cromáticas clinicamente aceitáveis, enquanto os outros dois se mantiveram estáveis. / Owing to the fact that pigmented silicons used in the making of facial prosthesis or the rehabilitation of patients with facial flaws present , in clinical experience, chromatic alteration as time passes by, and due to the shortage of experimental papers in the specific literature, specially in relation to industrial silicon of acetic cure, the present paper targets to verify the behavior of three types of different silicons colored with a determined pigment (facial make up powder), used as routine in facial prosthesis. The used silicons were: one of cure by heat (HTV) with medical purposes , one of acetic cure (RTV) for industrial purposes with specific nutritious rules and another one of acetic cure (RTV) with industrial rules only. To perform the experiment thirty bodies of proof were made , ten to each silicon type, which were analyzed through spectrophotometer. After analyzing, each group was divided into two sub groups, five units each, one group exposed (E) and one group control (C). The three groups (E) passed through accelerated environmental exposure aging, while the three groups (C) stayed in a totally dark place at normal temperature. The initial reading was considered pattern, while the following readings were within 45 and 90 days. The data from the three measurements were used for evaluating the chromatic alterations. With the statistic results at hand, we came to the conclusion that all silicons exposed showed unacceptable clinical color alteration, and in the control groups only the industrial acetic cure silicon (RTV) with specific nutritious rules, showed acceptable clinical chromatic changes while the other two remained stable.

A classificação de texturas coloridas sob diferentes condições de iluminação é um desafio na área de visão computacional, e depende da eficiência dos descritores de textura em capturar características que sejam discriminantes independentemente das propriedades da fonte de luz incidente sobre o objeto. Visando melhorar o processo de classificação de texturas coloridas iluminadas com diferentes fontes de luz, este trabalho propõe três novos descritores, nomeados Opponent Color Local Mapped Pattern (OCLMP), que combina o descritor de texturas por padrões locais mapeados (Local Mapped Pattern - LMP) com a teoria de cores oponentes; Color Intensity Local Mapped Pattern (CILMP), que extrai as informações de cor e textura de maneira integrada, levando em consideração a textura da cor, combinando estas informações com características da luminância da textura em uma análise multiresolução; e Extended Color Local Mapped Pattern (ECLMP), que utiliza dois operadores para extrair informações de cor e textura de forma integrada (textura da cor) combinadas com informações apenas de textura (sem cor) de uma imagem. Todos esses novos descritores propostos são paramétricos e, sendo o ajuste ótimo de seus parâmetros não trivial, o processo exige um tempo excessivo de computação. Portanto, foi proposto nesta tese a utilização de algoritmos genéticos para o ajuste automático dos parâmetros. A avaliação dos descritores propostos foi realizada em duas bases de dados de texturas coloridas com variação de iluminação: RawFooT (Raw Food Texture Database) e KTH-TIPS- 2b (Textures under varying Illumination, Pose and Scale Database), utilizando-se um classificador. Os resultados experimentais mostraram que os descritores propostos são mais robustos à variação de iluminação do que outros decritores de textura comumente utilizados na literatura. Os descritores propostos apresentaram um desempenho superior aos descritores comparados em 15% na base de dados RawFooT e 4% na base de dados KTH-TIPS-2b. / Color texture classification under varying illumination remains a challenge in the computer vision field, and it greatly relies on the efficiency at which the texture descriptors capture discriminant features, independent of the illumination condition. The aim of this thesis is to improve the classification of color texture acquired with varying illumination sources. We propose three new color texture descriptors, namely: the Opponent Color Local Mapped Pattern (OCLMP), which combines a local methodology (LMP) with the opponent colors theory, the Color Intensity Local Mapped Pattern (CILMP), which extracts color and texture information jointly, in a multi-resolution fashion, and the Extended Color Local Mapped Pattern (ECLMP), which applies two operators to extract color and texture information jointly as well. As the proposed methods are based on the LMP algorithm, they are parametric functions. Finding the optimal set of parameters for the descriptor can be a cumbersome task. Therefore, this work proposes the use of genetic algorithms to automatically adjust the parameters. The methods were assessed using two data sets of textures acquired using varying illumination sources: the RawFooT (Raw Food Texture Database), and the KTH-TIPS-2b (Textures under varying Illumination, Pose and Scale Database). The experimental results show that the proposed descriptors are more robust to variations to the illumination source than other methods found in the literature. The improvement on the accuracy was higher than 15% on the RawFoot data set, and higher than 4% on the KTH-TIPS-2b data set.

En vision par ordinateur, les points saillants sont des caractéristiques essentielles aux algorithmes. Les performances dépendent de paramètres extérieurs (ex. illumination). Les mesures de similarité sont centrales à la reconnaissance. Pour assurer l'efficacité de traitement, les caractéristiques extraites d'une image doivent être stables, et la mesure de similarité doit les distinguer parfaitement.Dans cette thèse, des caractéristiques conjointes géométrie/couleur sont étudiées : lignes de couleur et régions. Elles fondent la détection d'une troisième, la profondeur, qui sert en retour à évaluer leurs performanceLes lignes sont des extensions des classiques lignes de niveau: l'espace couleur 3-D est projeté sur un espace 1-D adapté pour résumer l'information chromatique là où elle est adéquate,Les régions exploitent classiquement la connexité image mais jointe à une compacité dans l'histogramme bidimensionnel issu du modèle dichromatique. L'homogénéité ainsi définie garantit une robustesse a priori aux variations d'éclairage en séparant la couleur de l'intensité et les couleurs entre elles.Cette homogénéité est exploitée selon 2 méthodes d'extraction d'ensembles compacts autour des modes de l'histogramme: extraction analytique des extrema locaux de couleur, extraction de ces mêmes extrema contrôlée par les régions correspondantes de l'image.Pour la profondeur, trois calculs de disparité stéréoscopique sont proposés et les performances comparées avec la réalité terrain:1. Appariement de lignes couleur avec une distance de Hausdorff revisitée.2. Exploitation de la forme des histogrammes de disparité par régions3.Coopération entre appariement de points et de régions. / In computer vision, salient points are essential features to algorithms. Performances depend on external parameters (e.g. illuminant). Similarity measures are central to recognition.To secure the processing efficiency, extracted features have to be stable enough, and the similarity measure needs to perfectly distinguish between them.In the thesis, joint geometrical and color features are studied: color lines and regions. They found the detection of a third one, range, that helps in turn to assess their goodness.Color lines are extensions of classical level lines: the 3 D color space is mapped onto a 1 D scale especially designed to retain the chromatic information where it is suitable.Regions require the usual image connectivity but in association with compactness in the bi-dimensional histogram stemming from the dichromatic model. The so-designed homogeneity is granting an a priori good robustness against illumination variations in separating the body colors and splitting color from intensity.The latter homogeneity gives raise to 2 methods for extracting compact sets around histogram modes: color first analysis (an analytic extraction of color local extrema) , and joint color/space analysis (same but controlled by the region growing).As for depth, 3 methods to compute the stereo disparity are proposed for their results to be confronted with the ground-truth:1. Color line matching based on a modified Hausdorff distance,2. Studying the shape of the disparity histogram between regions,3. Cooperation between pixel correlation and region matching.The robustness of the designed features is proved on several stereo pairs. Future work deals with improving efficacy and accuracy.

Um dos fatores imprescindíveis no resultado estético satisfatório do tratamento reabilitador protético ocular é a reprodução fiel da íris do olho remanescente na íris protética. É a dissimulação da perda para os pacientes afetados. Este trabalho apresenta duas novas técnicas de confecção da íris protética, utilizando imagem digitalizada da íris remanescente, obtida por meio de imagem fotográfica impressa em etiqueta autocolante e em adesivo. Em função da fotodegradação que compromete a longevidade das próteses oculares, decidiu-se avaliar a estabilidade das cores, comparando-se ambas as técnicas, através de teste de envelhecimento acelerado. Para os ensaios foram confeccionados corpos de prova simulando a íris protética, divididos em dois grupos: adesivo e etiqueta autocolante, nas cores verde, azul, marrom e preto. A variação do grau de degradação foi avaliada por leitura colorimétrica inicial e, em três intervalos semanais durante o envelhecimento artificial com radiação ultravioleta. A análise estatística sugere que quando as cores foram avaliadas em função do período de ensaio de envelhecimento artificial, somente na cor azul no grupo adesivo houve diferença estatisticamente significante. Quando avaliadas em função do grupo e período de ensaio, os testes estatísticos indicam que não houve diferença entre as cores entre adesivo. Nenhuma das cores entre os grupos apresentou uma degradação de cor acima do nível clinicamente aceitável. / One of the essential factors in satisfactory final result of ocular prosthetic rehabilitation treatment is a faithful reproduction of the iris of the eye remaining in prosthetic iris. It concealment loss for affected patients. This paper presents two new techniques to manufacture prosthetic iris, using the remaining iris scanned image, obtained by photographic image printed sticker and adhesive. Depending on the photo degradation that compromises the longevity of artificial eyes, decided to evaluate the stability of colors, comparing both techniques, through accelerated aging test. For the tests were prepared specimens simulating prosthetic iris, divided into two groups: adhesive sticker and, in green, blue, brown and black. The variation of the degree of degradation was evaluated by colorimetric reading before and after and three weekly intervals during aging with artificial ultraviolet radiation. Statistical analysis suggests that when the colors were evaluated according to the period of artificial aging test, only in blue color in the adhesive group difference was statistically significant. When evaluated as a function of group and trial period, the statistical tests indicate no difference between the colors of adhesive. None of the colors between the groups showed color degradation above the clinically acceptable level.

Motivos azuis recorrentes na última fase (1912 a 1914) do poeta austríaco Georg Trakl são comentados à luz de influências românticas. As imagens azuis desta lírica revelam vertentes românticas como o tributo à noite, a remitização, o clima crespuscular e de obscurecimento progressivo a partir do final do século XIX. A atribuição inusitada de cores a seres do mundo empírico traduz um procedimento comum às vanguardas plásticas e líricas deste período. / This study comments the recurrent blue motifs in the latest phase of poet Georg Trakl according to romantic influences. In this poems blue images reveal typical axes of Romanticism as the tribute to the night, remythologization and the progressive darkeness at the turn of the century. The uncommon use of blue color had become a hallmark of pictorial and poetical avant-garde of the 20th century.

Increased near infrared (NIR) reflection, closely resembling the red edge found in leaves, has been known in frogs for many years. Whereas previously thought of as an isolated rarity, we have shown that it is likely far more prevalent than previously believed, occurring in multiple distinct family groups and world regions. To date, there are now 26 anuran species known to demonstrate increased NIR reflectance, from 12 different genera, 4 families, and 3 ecozones. The visible/NIR reflection spectra of each individual measured was found to be characteristic of its species; whether it was wild or captive bred; and its sex. A machine learning based classification system was demonstrated as a viable method of identifying these properties from a frog's reflection spectra alone. How this reflection spectra developed from a pre-metamorphosis froglet through to adult frog was tracked, with the gradual changes to the reflection spectra of both NIR reflective and other frogs identified as being most likely dominated by the reduction in epidermal melanophores, and the increasing number of dermal iridophores. A modified consumer camera was shown to be a viable method for rapid identification of increased NIR reflection in anurans, and was used to identify that salamanders also show variation in NIR reflection between ground dwelling and leaf sitting species. The overnight colour change in Hylomantis lemur was observed, and found to occur pre-emptively of the frog's future location; with the frogs regularly transitioning from pale green ‘daytime' colouration, to the dark brown ‘night time' colouration, while still on the green leaf surface before becoming active, and undertaking the reverse transition while still active, but shortly before returning to the leaf. It seems likely that this change is for protection from silhouetting whilst active. Optical coherence tomography images were taken of several species of frog, and found to be a viable method for non-invasive investigation of anuran skin structure, with structural differences observed between the two colourations of H. lemur. It was found that the most likely cause of the increased NIR reflection in frogs is a reduction in melanin, either by absence or substitution with pterorhodin. Although the true benefit to the frog is difficult to determine, it seems likely that cryptic thermoregulation plays a key role: the maintenance of body temperature for the purpose of camouflage from animals capable of far-infrared vision. This thesis demonstrates the legitimacy of several techniques and approaches for non-invasive study of anurans, but the ultimate scope of the project is fundamentally limited by the range of frogs available. Further insight is likely to arise from increasing this scope, applying these techniques to more frogs, from more species, in more regions, and the author wishes all future researchers the greatest success in this endeavour.