The diploma theses focused on the topic of removing spectral aberration of sensor. The anomaly is being called spectral smile effect, or spectral curvature. Usually are with this artifact affected hyperspectral sensors, whose sensing is based on principle corresponding to pushbroom scanner. The defect occurs in the data as brightness gradient in the cross-track direction to the sensor flight and affects the object's spectral characteristics shape. Removing is important particularly in case of applying atmospheric correction algorithm, which are being degraded with presence of this defect. The work contents description of current methods used for detecting and eliminating this anomaly. The work is closer focused on the methods removing the defect based on own measured data without use of calibration targets. There is being examined sensitivity of the methods on the scene perception character, meaning heterogeneity of the scene and other outside influence. One of the methods is deeply processed resulting in increasing quality of the method for removing the defect.

A calibração de instrumento é reconhecida como um importante processo para a garantia de qualidade de dados obtidos a partir de um laser scanner terrestre (TLS). Um aspecto importante na garantia da qualidade de nuvem de pontos tridimensionais capturadas com instrumentos TLS é a calibração geométrica. Erros sistemáticos inerentes aos instrumentos, se não corrigidos, podem degradar a acurácia da nuvem de pontos obtida pelo scanner. A modelagem destes erros sistemáticos e o uso de metodologias de calibração para estimativa dos coeficientes do modelo permitem quantificar e avaliar a qualidade e a acurácia dos sistemas lasers scanners terrestres. Identificar os diferentes erros inerentes ao equipamento ou ao processo de medição é um fator de grande importância para certificá-los, comprovando sua conformidade com a precisão nominal definida pelos fabricantes. Esta dissertação apresenta propostas de diferentes metodologias para aferição e calibração de laser scanners terrestres. A primeira metodologia refere-se à auto-calibração de TLS que permite obter os parâmetros de calibração referentes aos erros sistemáticos de distância (??), colimação (?C), direção horizontal (??) e o erro de índice vertical (??). Dois equipamentos foram submetidos à auto-calibração, um equipamento novo, recém-fabricado, modelo Faro Focus 3D X330, que foi utilizado como referência, e um equipamento antigo, modelo Faro Photon 80, que devido ao tempo de constante uso foi submetido à aferição. Os resultados comprovaram a eficiência da metodologia de auto-calibração na determinação dos parâmetros de correção sistemática adicional, indicando que o scanner novo apresentou resultados dentro das especificações e o modelo antigo, resultados acima dos valores de precisão definidos pelo fabricante. Visando facilitar os procedimentos de campo e escritório para fins de calibração de TLS foram propostas duas metodologias com a utilização de peças fabricadas para uso no presente trabalho, visando a obtenção da acurácia tridimensional de um TLS. A primeira consiste na utilização de uma placa de aço com nove furos sobre os quais são alojadas nove esferas de poliacetal. A segunda consiste na utilização de um sistema tridimensional de planos perpendiculares, através do qual pode-se obter a acurácia 3D do TLS. Os resultados obtidos comprovam a eficiência das duas metodologias propostas, aplicadas em procedimentos de calibração em laboratório utilizando varreduras em equipamentos de curto alcance. Por fim foram realizados testes para determinação dos parâmetros de calibração relativos ao erro de zero ou constante aditiva, o erro de escala e o erro cíclico em linhas bases de calibração EDM, utilizando-se a rede de pilares da USP. Os resultados comprovam a necessidade de contar com distâncias entre pilares menores para utilização em TLS de curto alcance, porém, para laser scanners com maior autonomia de distância se mostrou um método eficiente. / Instrument calibration is recognized as an important process for quality assurance of data obtained from a terrestrial laser scanner (TLS). An important aspect in ensuring the quality of three-dimensional point cloud captured with TLS instruments is geometric calibration. Systematic errors inherent in the instruments, if not corrected, can degrade the accuracy of the cloud of points obtained by the scanner. The modeling of these systematic errors and the use of calibration methodologies to estimate the coefficients of the model allow quantifying and evaluating the quality and accuracy of the laser systems. Identifying the different errors inherent in the equipment or the measurement process is a factor of great importance to certify them, proving their conformity with the nominal precision defined by the manufacturers. This dissertation presents proposals of different methodologies for calibration of terrestrial laser scanners. The first methodology refers to TLS self-calibration, which allows to obtain the calibration parameters for systematic errors of distance (??), collimation (?C), horizontal direction (??) and vertical index error (??). Two devices were submitted to self-calibration, a new, newly manufactured Faro Focus 3D X330 model, which was used as reference, and an old equipment, Faro Photon 80 model, which due to the time of constant use was subjected to the calibration . The results proved the efficiency of the self-calibration methodology in determining the additional systematic correction parameters, indicating that the new scanner presented results within the specifications and the old model, values above the precision values defined by the manufacturer. In order to facilitate the field and office procedures for TLS calibration purposes, two methodologies were proposed with the use of prefabricated parts to obtain the three-dimensional accuracy of a TLS. The first proposes the use of a steel plate with nine holes on which are housed nine spheres of polyacetal. The second refers to the use of a three-dimensional system of perpendicular planes, where from the point cloud of the different planes the 3D accuracy of the TLS can be obtained. The results obtained prove the efficiency of the two proposed methodologies, applied in laboratory calibration procedures using short-range scans. Finally, tests were carried out to determine the calibration parameters related to the error of zero or additive constant, the scale error and the cyclic error in EDM calibration baselines, using the USP\'s network of columns. The results confirm the need for adequacy of the distance between columns for use in short-range TLS, but for laser scanners with greater distance autonomy an efficient method was shown.

O sistema desenvolvido obteve boa resposta na detecção de modelos numéricos de tumores com dimensões a partir de 5mm, representada na localização adequada e determinação do tamanho obtidos por meio de simulações envolvendo os modelos dos blocos especificados. Como objetivo principal do trabalho será apresentado o projeto, fabricação e resultados de testes de um circuito integrado gerador de pulsos com o formato da derivada de quinta ordem do pulso de gaussiano (transmissor UWB) fabricado utilizando a tecnologia IBM 0.18 CMOS. Os blocos principais que formam o circuito gerador de pulso são: circuito gerador de onda quadrada, gerador de atrasos, detector de fase e etapa de saída (formador de pulso). O gerador de onda quadrada foi implementado a partir de um buffer de RF com um inversor na saída com casamento de impedância. O gerador de atrasos foi implementado a partir de uma cascata de inversores. O circuito detector de fase é composto por bloco n- dinâmico , n-latch e inversor estático para forma pulsos em alta velocidade. As dimensões dos transistores foram definidas de modo a obter característica adequada de um pulso Gaussiano de 5ª ordem, considerando especificações exigidas de Sistema de Detecção de Câncer de Mama. Foi implementado o leiaute em full Custom com dimensões mínimas da tecnologia. Cinco chips diferentes foram testados. E os valores da fonte de alimentação foram variadas em 1,62V, 1,80V e 1.98, então foram medidos os valores de saída pico a pico e largura de pulso para cada chip. O consumo de energia medido foi de 244 uW, e a amplitude do pulso de saída 115,2 mV pico a pico e largura de pulso de 407,8 ps com um sinal de entrada senoidal de amplitude 806mVp à 100 MHz . O pulso gerado pelo gerador de pulso resultou em uma PSD (Power Spectral Density) com largura de banda de 0,6 GHz a 7,8 GHz, que é adequado para aplicações de UWB para detecção do câncer de mama. / As a result for detecting the numeric representation, the system could identify tumors from 5mm of extent with adequate localization, as well size determination. The primary goal of this work, therefore, is to bring out the project, manufacturing process and achieved results of tests regarding an integrated circuit for generating pulses which are shaped as the derivative of fifth order of the Gaussian pulse (UWMB transmitter) using the UWB 0.18 CMOS. The pulse generator circuit is composed by: circuit for generating square waves, delay generator, phase detector and output stage. The generator of square wave was implemented from one buffer of rf, with an inverter in the output and impedance matching. The delay generator was implemented from one cascade of inverters. The circuit for detecting the stages is assembled with n block dynamic, n-latch and static inverter for quickly generating pulses (high speed pulse generation). The dimensions of the transistors were defined in order to obtain the adequate characteristics of one Gaussian pulse of 5th order, considering the required specification of the Detection System for Cancer of Breast. It was implemented using the full Custom layout, taking into account the minimum dimensions for such technology. Five different chips were tested. The values of the source energy varied among 1,62V, 1,80V and 1,98V, being later measured the output values, peak to peak, as well the pulse width for each chip. The measured energy consumption was 244 uW, the amplitude of the output pulse was 115.2 mV peak to peak, and the pulse width was 407,8ps with sinusoidal input signal of 806mVp amplitude at 100MHz. As a result, it was obtained a PSD (Power Spectral Density) with band width of 0,6GHz to 7,8GHz from the pulse generator, which is quite adequate for UWB applications for detecting the breast cancer.

L’objectif de cette thèse est l’étude et le développement d’un outil de planification de trajectoires adaptatives guidée par robot afin d’assister l’insertion des aiguilles biseautées semi-rigides en procédures percutanées sous imagerie scanner ou IRM. L’approche est basée sur un nouveau modèle de la déflexion de l’aiguille qui permet une prédiction hors ligne des déformations de l’aiguille et une amélioration des performances d’insertion en ligne. Cette amélioration permet de compenser les incertitudes sur les connaissances de l’environnement et les approximations lors de la modélisation de l’aiguille. Les résultats des tests in vitro pour différentes plateformes robotiques ont confirmé la viabilité de la méthode proposée. / The goal of this thesis is the study and development of a tool for robot-driven adaptive needle insertion planning in order to assist percutaneous insertions of beveled semi-rigid needles guided by CT or MR images. The approach is based on a novel needle deflection prediction model that provides offline predictions and improve online the needle insertion performance. This improvement allows to compensate for environment uncertainties and approximations of needle-tissue interactions modeling. Results obtained from in vitro tests, using different robot platforms confirmed the viability of our method.

"Modern ultrasound scanners are portable and have become very useful for clinical diagnosis. However, they have limitations for field use purposes, primarily because they occupy both hands of the physician who performs the scanning. The goal of this thesis is to develop a wearable voice-controlled ultrasound scanner system that would enable the physician to provide a fast and efficient diagnosis. This is expected to become very useful for emergency and trauma applications. A commercially available ultrasound scanner system, Terason 2000, was chosen as the basis for development. This system consists of a laptop, a hardware unit containing the RF beamforming and signal processing chips and the ultrasound transducer. In its commercial version, the control of the ultrasound system is performed via a Graphical User Interface with a Windows-application look and feel. In the system we developed, a command and control speech recognition engine and a noise-canceling microphone are selected to control the scanner using voice commands. A mini-joystick is attached to the top of the ultrasound transducer for distance and area measurements and to perform zooming of the ultrasound images. An eye-wear viewer connected to the laptop enables the user to view the ultrasound images directly. Power management features are incorporated into the ultrasound system in order to conserve the battery power. A wireless connection is set up with a remote laptop to enable real-time transmission of wireless images. The result is a truly untethered, voice-controlled, ultrasound system enclosed in a backpack and monitored by the eye-wear viewer. (In the second generation of this system, the laptop is replaced by an embedded PC and is incorporated into a photographer’s vest). The voice-controlled system has to be made reliable under various forms of background noise. Three command and control speech recognition systems were selected and their recognition performances were determined under different types and levels of ambient noise. The variation of recognition rates was also analyzed over 6 different speakers. A detailed testing was also conducted to identify the ideal combination of a microphone and speech recognition engine suitable for the ultrasound scanner system. Six different microphones, each with their own unique methods of implementing noise cancellation features, were chosen as candidates for this analysis. The testing was conducted by making recordings inside a highly reverberant acoustic noisy chamber, and the recordings were fed to the automatic speech recognition engines offline for performance evaluation. The speech recognition engine and microphone selected as a result of this extensive testing were then incorporated into the wearable ultrasound scanner system. This thesis also discusses the implementation of the human-speech interface, which also plays a major role in the effectiveness of the voice-controlled ultrasound scanner system."

A Área de Proteção Ambiental do Banhado Grande na Bacia Hidrográfica do rio Gravataí, inserida na região metropolitana de Porto Alegre, abriga uma extensa Área Úmida em sua porção central. A partir de técnicas de Sensoriamento Remoto e Geoprocessamento para a análise das variáveis físicas como, geologia, cota altimétrica, pedologia e índices de vegetação como o NDVI e o NDWI, foi possível classificar compartimentos de Unidades de Paisagem associados às Áreas Úmidas em: Unidade de Paisagem Turfeira e Unidade de Paisagem / Planície de Inundação. A delimitação destas áreas, visa o planejamento do uso racional destes ambientes para a sua manutenção e preservação. No início da década de 1970, um trecho do rio Gravataí foi canalizado, com objetivo de drenar as Áreas Úmidas e viabilizar a expansão das áreas de cultivo do arroz, esta intervenção ocasionou um processo erosivo em forma de voçoroca no Banhado Grande, no município de Glorinha. A partir de uma série temporal de imagens satelitais foi possível mapear e quantificar a evolução do processo erosivo da voçoroca entre os anos de 2003 a 2015. Os resultados do mapeamento mostraram um aumento de quatro vezes na área da voçoroca de 2909,62 m² em 2003 para 12097,70 m² em 2015. No mapeamento da voçoroca e no monitoramento dos processos erosivos no banhado foram o uso das técnicas como: a) monitoramento por estaqueamento; b) mapeamento por imagens de satélite; b) mapeamento por varredura de Laser Scanner Terrestre. O Laser Scanner Terrestre mostrou-se uma ferramenta potencial para o mapeamento da voçoroca em virtude de sua alta precisão e rapidez na coleta de dados no campo, gerando modelos digitais de elevação com alta precisão. O uso do modelo permitiu identificar áreas de erosão deposição e de sedimentos, a partir do perfil topográfico. É necessário o monitoramento contínuo do processo erosivo na área do Banhado Grande, combinando métodos para modelar a sua dinâmica. Essas ferramentas de apoio são fundamentais para a elaboração do Plano de Manejo e estudos que visam a restauração das Áreas Úmidas do rio Gravataí. / The Banhado Grande Environmental Protected Area in the Gravataí river basin, located in the metropolitan area of Porto Alegre, has an extensive wetland area in its central portion. From remote sensing and geoprocessing techniques for the analysis of physical variables such as geology, topography, pedology and vegetation indices such as NDVI and NDWI, it was possible to classify compartments of Landscape Units associated to Wetlands in: Peat Landscape Unit and Landscape Unit / Flood Plain. The delimitation of these areas, aims at planning the rational use of these environments for their maintenance and preservation. In the beginning of the 1970s, a section of the Gravataí river was channeled, with the objective of draining the wetlands and making possible the expansion of rice cultivation areas, this intervention caused an erosive process in the form of gully in Banhado Grande, in the municipality of Glorinha. From a time series of satellite images, it was possible to map and quantify the evolution of the erosion process of the voçoroca between the years 2003 to 2015. The results of the mapping showed a significant increase in the gully of 2909.62 m² in 2003 to 12097.70 m² in 2015. In the mapping of gully and in the monitoring of the erosive processes in the swamp, were used techniques such as: a) stacking monitoring; b) mapping by satellite images; b) scanning mapping of terrestrial Laser Scanner. The terrestrial Laser Scanner has proved to be a potential tool for the mapping of the gully because of its high precision and rapid data collection in the field, generating digital elevation models with high precision. The use of the model allowed identifying areas of erosion deposition and sediment from the topographic profile. It is necessary, however, to choose suitable techniques for the continuous monitoring of the erosive process in the area of the Grande Banhado, combining methods to model the dynamics. These support tools are fundamental for the elaboration of the Management Plan and studies that aim at the restoration of the wetlands of the Gravataí river flood plain.

Le scanner laser est un périphérique permettant d'analyser un objet réel et d'extraire des informations de sa surface. Grâce à cet outil, il est possible d'obtenir la représentation numérique de tout ou partie de la surface frontière d'un objet réel. Les scanners laser sont livrés avec un logiciel permettant de faire l'acquisition des données brutes, le recalage des différentes parties acquises et la reconstruction de la surface. Cette suite d'opérations permet de construire le modèle numérique et est communément appelée pipeline 3D d'acquisition. Dans cette thèse, nous développons notre pipeline, que nous nommons A2RI, et y ajoutons une étape d'impression. Ce pipeline permet la reproduction d'un objet à partir de son acquisition au scanner laser. Nous veillons particulièrement à quantifier et maîtriser l'erreur commise dans chaque maillon de la chaîne grâce à des mesures euclidiennes et géodésiques sur l'objet réel et le modèle numérique. / Abstract

Avec l’augmentation du nombre de scanner et de la dose collective, le risque potentiel d’apparition d’effets stochastiques est accentué. Pour limiter au maximum ce risque, les principes de justification et d’optimisation doivent être appliqués avec rigueur. L’optimisation des pratiques a pour but de délivrer la dose la plus faible possible tout en conservant une qualité diagnostique des images. C’est une tâche complexe qui implique de trouver en permanence un compromis entre la dose délivrée et la qualité image résultante. Pour faciliter cette démarche, des évolutions technologiques ont été développées. Les deux évolutions majeures sont la modulation du courant du tube en fonction de l’atténuation du patient et l’apparition des reconstructions itératives (IR). L’introduction des IR a modifié les habitudes puisqu’elles permettent de conserver des indices de qualité image équivalents en réduisant les doses. Cependant, leurs utilisations s’accompagnent d’une modification de la composition et de la texture de l’image nécessitant d’utiliser des métriques adaptées pour les évaluer. Le but de cette thèse est d’évaluer l’impact d’une utilisation des IR sur la réduction de la dose et sur la qualité des images afin de proposer en routine pour tous les patients, des protocoles avec la dose la plus faible possible et une qualité image adaptée au diagnostic. La première partie de cette thèse est consacrée à une mise au point sur la problématique du compromis dose/qualité image en scanographie. Les métriques de qualité image et les indicateurs dosimétriques à utiliser, ainsi que le principe et l’apport des reconstructions itératives y sont exposés. La deuxième partie est consacrée à la description des trois étapes réalisées dans cette thèse pour atteindre les objectifs. La troisième partie est constituée d’une production scientifique de 7 articles. Le 1er article présente la méthodologie d’optimisation globale permettant la mise en place de protocoles Basses Doses en routine avec utilisation de niveaux modérés des IR. Le 2ème article évalue l’impact et l’apport sur la qualité des images obtenues pour des niveaux de doses très bas. Le 3ème et le 4ème article montrent l’intérêt d’adapter ou de proposer des protocoles optimisés selon la morphologie du patient. Enfin les 3 derniers articles, illustrent la mise en place de protocoles Très Basses Doses pour des structures ayant un fort contraste spontané. Pour ces protocoles les doses sont proches des examens radiographiques avec des niveaux élevés des IR. La démarche d’optimisation mise en place a permis de réduire considérablement les doses. Malgré une modification de la texture et de la composition des images, la qualité des images obtenues pour tous les protocoles était jugée satisfaisante pour le diagnostic par les radiologues. L’utilisation des IR en routine nécessite une évaluation particulière et un temps d’apprentissage pour les radiologues. / The increasing number of scanner and the cumulative dose delivered lead to potential risk of stochastic effects. To minimize this risk, optimization on CT usage should be rigorously employed. Optimization aims to deliver the lowest dose but maintaining image quality for an accurate diagnosis. This is a complex task, which requires setting up the compromise between the dose delivered and the resulting image quality. To achieve such goal, several CT technological evolutions have been developed. Two predominant developments are the Tube Current Modulation and the Iterative Reconstruction (IR). The former lays one patient's attenuation, the latter depend on advanced mathematical approaches. Using IR allows one to maintain equivalent image quality values by reducing the dose. However, it changes the composition and texture of the image and requires the use of appropriate metric to evaluate them. The aim of this thesis was to evaluate the impact of using IR on dose reduction and image quality in routine for all patients, protocols with the lowest dose delivered with an image quality suitable for diagnosis. The first part of the thesis addressed the compromise between dose delivered and image quality. Metrics of the image quality and the dosimetric indicators were applied as well the principle and the contribution of IRs were explored. The second part targets the description of the three steps performed in this thesis to achieve the objectives. The third part of the thesis consists of a scientific production of seven papers. The first paper presents the global optimization methodology for the establishment of low dose protocols in routine using moderate levels of IR. The second paper assesses the impact and contribution of IR to the image quality obtained to levels very low doses. The third and the fourth papers show the interest to adapt or propose protocols optimized according to patient's morphology. Finally the last three papers illustrate the development of Very Low Dose protocols for structures with high spontaneous contrast. For these protocols, doses are close to radiographic examinations with high levels of IR. The optimization process implementation has significantly doses reduction. Despite the change on the texture and on composition of the images, the quality of images obtained for all protocols was satisfactory for the diagnosis by radiologists. However, the use of routine IR requires special assessment and a learning time for radiologists.

Vermont is the first and only state in the US to establish mandatory labels for food containing genetically modified organisms (GMOs). This thesis investigates the impact of the mandatory labeling law as it relates to changes in prices, quantities sold, and opinions of GMOs. First, grocery store scanner data from Vermont and Oregon are compared using triple difference (difference-in-difference-in-difference) models. Next, Vermont, Oregon, and Colorado survey response data are compared using difference-in-difference models. The findings reveal that there is a general price premium for non-GMO goods of $0.05/oz across all states and times, that mandatory labeling laws do not result in a short-term change in quantities sold or prices of GMO products, and that both mandatory labeling laws and failed mandatory labeling referendums cause an increase in support for GMOs in the food supply. The implications of this research are that mandatory GMO labels did not impact short-term prices or sales and increased the level of support for GMOs.

Une chaîne de traitement a été mise en place permettant de reproduire des mouvements physiologiques afin d’en étudier l’influence et tester les solutions pour y pallier. Une méthodologie originale, basée sur des acquisitions échographiques « Doppler Tissue Imaging », a permis de quantifier les mouvements tridimensionnels de contraction cardiaque. Ces données ont alors servi à optimiser le placement des fenêtres temporelles d’acquisition/reconstruction, à quantifier la résolution temporelle minimum pour geler le mouvement cardiaque le long de son cycle et de données d’entrées de commande d’une plateforme de mouvement et pour un simulateur informatique. Une étude dynamique menée sur des modélisations de calcifications d’artère coronaire a montré l’influence du mouvement respiratoire et la nécessité de l’intégrer dans le processus d’acquisition. Des premiers algorithmes d’estimation et de correction du mouvement ont également été testés sur des données brutes réelles et simulées. / The new idea presented in this work takes into account patient motion in the acquisition and reconstruction processes. For this work, the complete acquisition system has been developed in order to reproduce physiologic motion, analyse their effect and propose correction methods to reduce image artefacts. A new methodology based on Doppler Tissue Imaging was used to find the motion in three dimensions of several coronary artery segments. Based on these data, optimal temporal windows were defined for reconstruction and an analysis of the ideal temporal window in the heart cycle was proposed. Both motion models were then used the control of a motion platform and as input for computer simulations. A first analysis carried on coronary calcification showed the influence of respiratory motion. Estimation and correction of motions were then performed on CT raw data and simulated motion. This works shows that it is necessary to include motion in the acquisition/reconstruction algorithms in CT.