Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 6 uppsatser.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves [106]-128).

Thesis (MPhil)--University of Melbourne, Centre for Neuroscience, The Howard Florey Institute, 2009. / Typescript. Includes bibliographical references (leaves 137-160)

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2004. / Thesis advisor(s): Gamani Karunasiri, Xiaoping Yun. Includes bibliographical references (p. 47-50). Also available online.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 75-84).

En raison de l’incompatibilité des méthodes chromatiques architecturales promues en Iran dans les deux phases récentes de modernisation avec les conditions du milieu géographique et culturel, nous nous interrogeons sur la spécificité du sens de la couleur et de son rôle dans la spatialité persane. La couleur peut-elle être encore considérée comme un facteur structurant dans une situation où la ville affronte une forte tendance à l’uniformisation de son cadre bâti ? Si nous avons focalisé nos analyses à partir d’Ispahan d’un point de vue historique et théorique, c’est dans la mesure où l’urbanisme traditionnel comme les transformations contemporaines de cette ville permettent d’opérer une coupe épaisse et transversale dans l’ensemble de la société persane et iranienne. Si le point de départ de notre travail a d’abord consisté à analyser le sens et les valeurs des rapports entre couleur(s) et espaces, architectural et urbain, contemporains persans, après plusieurs années de recherche, notre point d’arrivée - et notre thèse principale - consiste à dire que les effets optiques et tactiles ou haptiques des couleurs dans l’espace architectural et urbain dépendent fondamentalement de l’interprétation donnée à la profondeur. Qu’entendre en effet par ce concept, complexe, et ses mises en œuvre urbanistiques dans le contexte de la culture persane ? C’est dans cette logique que nous essayons de projeter un nouveau regard vis-à-vis de la troisième dimension et de son expression par l’usage des couleurs à la fois dans la conception des habitats modernes à Ispahan mais aussi dans les projets d’aménagement urbain actuel de cette ville. / Because of the discordancy between the chromatic architectural strategies put forward in Iran during two of its most recent phases of modernization and Iran’s broader geographic and cultural context, I have set out to question the specificity of the sense of colour and its role in Persian spatiality. Can colour still be considered a structural factor in a city faced with the current trend towards uniform built environments? If I have focused my analysis on Ispahan from a historical and theoretical point of view, it is because traditional urban planning as well as the contemporary transformations of the city encompass a significantly broad and transversal sample of the entire Persian and Iranian society. If the point of departure of my work has been to analyse the sense and value of the relationships between contemporary Persian colour(s) and architectural and urban spaces, my point of arrival, and main thesis after many years of research, consists in saying that the optic and haptic effects of colour in architectural and urban spaces depend fundamentally on the interpretation that is given to depth. How can we understand this complex concept and its urban development usage in a Persian cultural context? It is following this logic that I will try to develop a new perspective on the third dimension and its expression by means of the use of colour, within both the understanding of Ispahan’s inhabitants, and the city’s actual urban development projects.

L’objectif de ces travaux de thèse est de faire la preuve de concept, la validation expérimentale et la réalisation de système de mesure de champ électrique pour la caractérisation de câbles monoconducteur, multiconducteurs ou d’équipements de tension basse fréquence en environnement industriel. Ces travaux répondent à des problématiques de diagnostic énergétique ou de caractérisation d'appareillage haute tension. Le système permet une mesure vectorielle, sans contact des champs rayonnés par les conducteurs afin de s’affranchir de la nécessité d’habilitation électrique (aucune ouverture d’armoire électrique) et surtout sans nécessiter l’interruption de la chaîne de production. Les mesures sont faites en temps réel et permettent d’obtenir des informations sur les tensions, les phases ou encore les positions des conducteurs au sein d’un câble. Deux technologiques différentes sont proposées afin de répondre à cette problématique. La première technologie développée est basée sur l’effet Pockels et amène à la réalisation de sonde électro-optique totalement diélectrique donc non invasive pour la mesure. Cette sonde électro-optique permet, selon la configuration, la mesure des trois composantes du champ électrique. Cette première technologique est utilisée pour les systèmes haute tension. Une deuxième technologie, électrique, permet de répondre aux attentes des industriels en termes de coût et est utilisée pour des applications basse tension, comme le diagnostic électrique des câbles de tension. Un autre aspect a été développé dans le cadre des travaux de thèse afin de proposer une mesure puissancemétrique. Une technologique qui permet la mesure de champs magnétiques pour compléter les informations relatives aux câbles ou équipements industriels a été développé. Cette mesure se fait également sans contact et permet d’obtenir des informations sur le courant et ainsi déduire des informations sur la puissance. Le système électro-optique a permis de caractériser des systèmes haute tension tels que des câbles, des isolateurs ou encore des appareillages de commutation à isolation gazeuse (GIS). Le système électrique (pince puissancemétrique) a permis la caractérisation complète de câble d'énergie: position des conducteurs, tension des conducteurs, courant, phase, détection d'harmoniques ou mesure de décharges partielles. / The aim of this work is to propose the proof of concept, the experimental validation and the realization of electric field measurement system for the characterization of cables (single or multicore) or low frequency voltage equipment in industrial environment. The problematic are the energy diagnostics and high voltage device characterization. The developed system allows a conctact-less vector measurement of the fields radiated by drivers without requiring the interruption of the production chain. The measurements are made in real time and allow to obtain information about the voltage, the phase or the positions of the conductors in a cable. Two different technologies are proposed to address this problem. The first developed technology is based on the Pockels effect and leads to the realization of an electro optic probe totally dielectric and non invasive for the measurement. This electro optic probe allows, depending on the configuration, to measure the three components of the electric field. This technology is used, mainly, for high voltage applications. A second technology, based on electric sensors, is suitable for the industrial's expectations in terms of cost. It is used for low voltage applications such as electric diagnostics voltage cables. A complementary study has been developed to propose a wattmeter clamp. Thus, a technology allowing to measure the magnetic field has been implemented. This development is also contactless and provides information on the current in order deduce information on power. The electro-optical system has allowed characterization of high-voltage systems such as cables, insulators or switchgear gas-insulated (GIS). The electrical system (wattmeter clamp) offers a complete characterization of power cable: position of drivers, voltage drivers, current, phase, harmonic detection or measurement of partial discharge.

Le but de ce travail de thèse est de doter la métrologie française d'un instrument de référence dédié à la caractérisation métrologique des propriétés réflectives des objets qui, du point de vue de l'apparence, sont à l'origine des sensations de couleur, de brillant, de texture, de translucidité…etc. Ce mémoire décrit la conception, réalisation et mise au point d'un dispositif de mesure de la fonction de distribution bidirectionnelle du facteur de luminance d'une surface plane (BRDF). La BRDF est la grandeur physique qui caractérise intégralement la réflexion lumineuse à la surface d'un matériau. En cela, sa mesure s'inscrit comme un outil indispensable pour la mesure de l'apparence car elle permet de connaître en détail le signal qui entre dans l'œil.Certaines surfaces présentent une apparence pigmentée, métallisée, nacrée ou encore interférentielle, ces surfaces, dites "goniochromatiques", ont la capacité de changer d'apparence en fonction de l'angle d'observation. Pour les caractériser, il est impératif d'effectuer une mesure de BRDF sous plusieurs conditions d'observation et d'illumination. L'outil de mesure de la BRDF est un gonioréflectomètre, dédié à des mesures dans le domaine UV - Visible (250 nm – 900 nm).Le montage expérimental consiste en deux lignes distinctes. La première, appelée voie spectrale, est dédiée à l'étude de la couleur. Elle est constituée d'une illumination fixe assurée par une lampe à décharge de xénon filtrée par un monochromateur puis focalisée sur la surface étudiée. La détection, mobile, est assurée par un système optique constitué de lentilles et de miroirs qui servent à renvoyer la lumière réfléchie par la surface sur la photodiode.La deuxième ligne, appelée voie spatiale, est la dédiée à l'étude du brillant. Elle requière une résolution angulaire qui égale l'acuité visuelle de l'œil humain (0,03°) c'est cette partie qui introduit l'originalité de notre instrument. Sur cette voie, la détection est fixe et est basée sur la combinaison d'une optique de Fourier et d'une caméra CCD (512x512 pixels). L'illumination est mobile et est assurée par une lampe incandescente à filament de tungstène collimatée sur l'échantillon.Les deux lignes partagent un robot porte-échantillon qui offre six dégrées de liberté qui sert à reproduire toutes les directions d'illumination et d'observation au-dessus de l'échantillon.Mots clés : Couleur, Brillant, BRDF, Goniochromatisme, Pic spéculaire. / The aim of this thesis is to provide the French Metrology with a reference instrument that can be used for measuring the appearance of objects. Several physical properties of object appearance are used not only to identify the object itself but also determine its quality. These include color, gloss, texture and translucency. This work describes the design, characterization and the implementation of an instrument that has been built particularly to measure the bidirectional reflectance distribution function (BRDF) of planar surfaces. BRDF is a physical quantity that enables measuring the surface color and gloss. Accordingly it is important to ensure accurate and traceable measurements of such a quantity in order for a comprehensive understanding of surface properties to be fulfilled.Some surfaces show pigmented, metallic, sparkling or pearlescent appearance. These surfaces, called goniochromatic surfaces, have the ability to change their appearance depending on the viewing angle. To characterize them, it is necessary to deliver surface reflectance measurements at several directions and under different illumination conditions. The instrument that enables these measurements is called gonioreflectometer.The experimental setup we have designed consists of two separate detection lines. The first line, called "color line", is used to study the color. It consists of a stationary illumination source that uses a xenon lamp spectrally resolved by a monochromator. The light coming out from the source is focused on the surface under investigation. The reflected light by the surface is collected by using a lens and directed onto a photodiode by a mirror. This detection system can be moved over a wide angular range so as to measure the BRDF.The second line, called "gloss line", is used to measure the gloss of the surface. In order to be very close to the average human observer, high angular resolution is required. In this line the detection part is stationary. It consists of a Charged Coupled Device (CCD) camera of 512 x 512 pixels. The source used to illuminate the surface is an incandescent tungsten lamp. Angular measurements in this line are provided by the movement of the illumination source itself. Both color and gloss lines share a robot sample-holder that provides six degrees of freedom. This of course facilitates measurements over varies detection and illumination directions of the sample.Key words: Color, Gloss, BRDF, Goniochromatisme, Specular pic.

[pt] O objetivo deste trabalho foi o desenvolvimento de um sistema de medição de deformações utilizando redes de Bragg em fibras ópticas. Experiências preliminares empregando um analisador de espectro óptico comprovaram que a relação entre deformação e translação espectral do sinal refletido pelo sensor é linear. Baseado neste princípio, foi proposto um circuito óptico para a demodulação do sinal. Este circuito, de construção simples e barata, utiliza uma rede de Bragg como sensor e outra, com largura espectral bem maior, como filtro óptico. Dois fotodetectores são responsáveis pela recepção do sinal e por tornar o sistema auto-compensável. Dois métodos de calibração do sistema, um numérico e outro experimental, são apresentados e testados. A partir dos resultados das experiências, sugestões são feitas no sentido de melhorar os métodos de calibração. A automatização das calibrações e medições é proposta e um método de separação de efeitos de temperatura e deformação mecânica é apresentado. / [en] The goal of the present work has been to develop a fiber Bragg grating strain sensor system. Experiments with an optical spectrum analyzer have confirmed that there is a linear relationship between the strain in the gratting and the shift of the central wave length reflected by the sensor. Based on this measurement principle, a simple and inexpensive optical circuit for demodulation of the sensor s reflected signal has been developed. Two photodetectors are employed in order to reduce the influence of power fluctuations of the optical source as well as of other losses. The measurement system has been calibrated both numerically and experimentally with satisfactory agreement. Suggestions are made in order to improve the calibration techniques, and a method for decoupling the temperature effects from the strain measurement is proposed.

[pt] O presente trabalho investiga a utilização de fibras ópticas em biossensoriamento e na indução de uma não-linearidade de segunda ordem para a construção de dispositivos sensores. O biossensor proposto tem por finalidade diagnosticar uma das doenças com maior incidência em países tropicais: a Dengue. Foi construído um sensor a fibra óptica que potencialmente é capaz de diagnosticar, num tempo curto, a presença do vírus da Dengue no sangue de um paciente infectado. Esse sensor usa nanopartículas de ouro, depositadas na extremidade de uma fibra óptica, que foram funcionalizadas com os anticorpos da Dengue (anti-NS1). O sensor é capaz de detectar o antígeno NS1 em diferentes concentrações com um limite de quantificação de 0.074 micrograma por mililitro, podendo ser explorado para uso na fase aguda da infecção.Outra vertente do trabalho é a possibilidade de se realizar modificações estruturais nas fibras ópticas com o intuito de alterar as propriedades ópticas da fibra. Através da técnica de polarização térmica, é possível gravar campos elétricos da ordem de 108 volts por metro no núcleo da fibra óptica, sendo possível utilizar as fibras polarizadas como moduladores de fase e de amplitude, seletores de pulso, chaves ópticas, voltímetros, entre outras. O trabalho de tese aqui descrito apresenta um estudo detalhado da polarização térmica em fibras ópticas através de simulações, utilizando o software COMSOL Multiphysics, considerando-se os diversos parâmetros envolvidos e geometrias diferentes de fibras, visando a obtenção de uma alta não-linearidade de segunda ordem. Além do mais, experimentos foram realizados a fim de se entender o mecanismo presente no processo de polarização térmica face aos resultados obtidos pela simulação. Buscou-se, também, entender o papel dos portadores de cargas presentes no material no processo de geração de não-linearidade de segunda ordem realizando-se experimentos de polarização óptica. / [en] The present work investigates the use of fiber optics in biosensing and the creation of a second order nonlinearity to be use in the development of sensor devices. The goal of the proposed biosensor is to diagnose one of the diseases with highest incidence in tropical countries: Dengue. Dengue is a dangerous disease that every year affects more and more people, despite the efforts made to deal with the transmitter, the mosquito Aedes aegypti. Furthermore, since Dengue symptoms resemble flu symptoms, wrong diagnoses are frequently made. As a consequence, wrong medicines may be prescribed, and that may lead the patient to death. Another problem in diagnosing Dengue is the long time is necessary for the laboratorial exams to give a result. In an attempt to offer a solution that could minimize these problems, an LSPR-based fiber optic sensor was adapted for antigen NS1 detection. This sensor is potentially able to perform a Dengue s virus diagnosis in a short period of time in an infected patient s blood. It uses gold nanoparticles that are functionalized with Dengue s antibodies. The antibody, anti-NS1, was immobilized in gold nanoparticles deposited at the endface of a multimode optical fiber. The LSPR sensor is able to detect different concentrations of the antigen NS1 with a limit of quantification equal to 0.074 microgram per milliliter, and may be used in the acute phase of the infection. Another part of the present work investigates the possibility of performing structural modifications in the optical fiber to change the optical properties of silica. Through the electro-thermal poling technique it is possible to record electric fields as high as 108 volts per meter in the core of the fiber, making possible the use of these modified fibers as phase and amplitude modulators, optical keys, pulse selectors, voltmeters, etc. This work also shows a very detailed study of electro-thermal poling in optical fiber through simulations, using the software Comsol Multiphysics, considering various parameters that are involved in the process in order to obtain high second order nonlinearity. Furthermore, experiments on eletro-optical poling were performed to investigate the mechanism involved in this poling process, in order to understand the role of the carriers present in the material in the generation of the second order nonlinearity.