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1
Camilleri, Jérémy. "Dosimétrie in vivo des traitements de radiothérapie conformationnelle avec modulation d'intensité par imageur portal haute énergie au silicium amorphe." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2736/.
Повний текст джерелаАнотація:
La réalisation de la dosimétrie in vivo (DIV) en radiothérapie externe reste difficilement applicable dans le cadre d'irradiations conformationnelles avec modulation d'intensité (RCMI) où la mesure obtenue à l'aide de détecteurs ponctuels placés en entrée de patient est trop peu représentative de la dose réellement délivrée au volume cible. L'utilisation des imageurs haute énergie au silicium amorphe ("Electronic Portal Imaging Device", EPID) dans ce contexte est une alternative intéressante à condition de disposer en parallèle d'algorithmes permettant de convertir le plus précisément possible le signal de l'EPID en dose absorbée dans le patient. Ce travail de thèse s'inscrit donc dans cette démarche et consiste à développer des méthodes de calculs applicables en clinique permettant d'utiliser l'EPID pour la pratique de la DIV des traitements par RCMI. En premier lieu nous présentons le dispositif d'imagerie utilisé tout au long de ces travaux ainsi que la caractérisation de sa réponse en fonction de plusieurs paramètres d'irradiation. Une méthode permettant de déterminer la dose reçue par le patient en un point situé sur l'axe du faisceau à partir du signal de l'EPID a par la suite fait l'objet d'une étude sur 92 patients traités par RCMI dynamique pour des pathologies pelviennes. Dans un second temps, un algorithme de rétroprojection permettant de reconstruire la dose reçue par le patient en deux dimensions a été développé. Pour cela, le signal de l'EPID obtenu en sortie de patient est d'abord converti en dose absorbée dans l'eau par convolution de l'image avec plusieurs kernels de redistribution. La dose ainsi calculée est ensuite rétroprojetée par l'intermédiaire de facteurs correctifs dépendants de la morphologie du patient et de sa transmission. L'évaluation de la méthode a été réalisée sur 26 faisceaux issus de 6 plans de traitements différents d'abord en condition de prétraitement (i. E. Sans patient placé entre la source et le détecteur), puis sur fantôme homogène et enfin in vivo. L'introduction de fonctions d'atténuation dépendantes de la profondeur de calcul dans notre modèle a finalement permis d'obtenir un algorithme capable de reconstruire la dose dans le patient en trois dimensionsIn vivo dosimetry (IVD) is still a complex procedure for intensity-modulated radiation therapy (IMRT). The use of conventional point detectors does not give a good representation of the actual dose delivered to the target volume. On the other hand, EPID-based in vivo dosimetry methods appears to be an interesting and efficient option for carrying out such measurements provided that accurate algorithms allowing to convert EPID signal into patient absorbed dose are available. The present work consists in developing clinically applicable calculation methods to perform EPID-based IVD on intensity-modulated fields. As a starting point, the imaging device used throughout this work is described before considering its response with respect to several irradiation parameters. An IVD method enabling the calculation of the on-axis patient point dose from EPID signal was studied and evaluated for 92 pelvic cancer patients treated with IMRT. Then, a 2D back-projection in vivo dose reconstruction algorithm was developed. In this model, the EPID signal was first converted into absorbed dose in water by convolving the EPID image with dose redistribution kernels. The 2D dose distribution was then back-projected applying correction factors calculated from the patient morphology and transmission factor. The validity of the method was checked for 6 treatment plans (26 fields) in pretreatment situation (i. E. Without patient) with homogeneous phantom and finally in vivo. The last part of this work deals with the introduction of mathematical attenuation functions in order to devise a complete in vivo 3D dose reconstruction algorithm
2
Chatrie, Roudier Frédéric. "Dosimétrie in-vivo et contrôle qualité en radiothérapie externe par réseaux de neurones." Thesis, Toulouse 3, 2021. http://www.theses.fr/2021TOU30175.
Повний текст джерелаАнотація:
Le domaine de l'intelligence artificielle a subi un essor considérable ces dernières années, notamment avec l'arrivée du Deep learning. Des applications diverses peuvent bénéficier de ces modèles, à condition d'avoir suffisamment de données représentatives du système. Ces avancées scientifiques sont principalement dues aux prouesses tech- nologiques qui amènent des capacités de calculs notables avec l'utilisation des cartes graphiques. Les réseaux de neurones artificiels appliqués à la radiothérapie externe peuvent avoir un grand intérêt, notamment pour contrôler la qualité des traitements. Dans ce travail, une récente approche a été investiguée, basée sur des réseaux de neurones. Ceux-ci permettent de reconstruire une distribution de dose absorbée 2D à partir de l'imageur portal dont le signal est récupéré avant et pendant le traitement, respectivement, pour l'étape de contrôle qualité et de dosimétrie in-vivo. En appliquant des corrections sur ce signal, il est possible de vérifier que le patient a bien reçu ce qui lui avait été prescrit préalablement. Les modèles utilisés sont, soit des réseaux de neurones multi-couches de type feed-forward, soit des réseaux de neurones convolutionnels. Ils ont été appliqués à différents types de traitements tels que la radiothérapie conformationnelle ou celle à modulation d'intensité. De plus, plusieurs énergies d'irradiation ainsi que différentes marques d'accélérateurs de particules ont été prises en charge. Afin d'évaluer la qualité du modèle conçu, le critère clinique γindex a été utilisé. Des résultats tout à fait satisfaisants ont été obtenus pour la phase de contrôle qualité. Cependant, même si des résultats prometteurs pour la phase de dosimétrie in-vivo ont été montrés, il reste des améliorations à apporter pour pouvoir utiliser de tels algorithmes en routine cliniqueThe field of artificial intelligence have received a considerable amount of attention in recent years, particularly thanks to the arrival of Deep learning. A wide range of applications can benefit from these models, provided there is sufficient data that is representative of the system. These scientific advances are mainly due to technological progress that enables significant computing capabilities with the use of GPUs. Artificial neural networks applied in the domain of external radiotherapy can be of great interest, especially for controlling the quality of treatments. In this work, a recent approach was investigated based on neural networks. These make possible the reconstruction of 2D absorbed dose distribution from the portal imager whose signal is recovered before and during the treatment, respectively, for quality assurance and in-vivo dosimetry. By correcting this signal, it is possible to verify that the patient has accurately received the prescribed treatment. The models used are either feed-forward multi-layer neural networks or convolutional neural networks. They have been applied to different types of treatments, such as conformational or intensity-modulated radiotherapy. In addition, several irradiation energies as well as different particle accelerators manufacturers have been supported. In order to assess the quality of the design, the clinical criterion γindex was used. Completely satisfactory results were obtained for the quality assurance phase. However, although promising result for the in-vivo dosimetry phase have been shown, there are still improvements to be made to be able to use such algorithms in clinical routine
3
Lim, Seng Boh. "2d dose measurement using a flat panel EPID." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1609.
Повний текст джерелаАнотація:
The increasing use of intensity modulated radiation therapy (IMRT) to deliver conformal radiation treatment has prompted the search for a faster and more cost effective quality assurance (QA) system. The standard technique relies on the use of film for two-dimensional dose distribution verification. Although film is considered the gold standard and is widely used for this purpose, the procedures involved are relatively lengthy, labour intensive and costly for a multiple field IMRT verification. In this study, we investigate the use of an amorphous silicon electronic portal imaging device (a-Si EPID) to complement the film. The dosimetric behaviour of the device is studied both experimentally and numerically using the EGSnrc Monte Carlo simulation routine. The intrinsic build-up of the flat panel EPID was found to be 1.1 cm of water equivalent material. The response of the flat panel EPID was found to be linear between 0 and 300 cGy. To calibrate the flat panel EPID for two dimensional dose measurements, the deconvolution method was chosen. The scatter dose kernel required for this calibration method was calculated and characterized by varying the energy, spectrum and phantom material using a 6MV pencil beam. We found that flat panel EPID scatter kernel has as much as 80% more scattering power than the water scatter kernel in the region 1 cm away from the center of a 6MV pencil beam. This confirms that a flat panel EPID behaves significantly differently from water dosimetrically and requires an accurate dose scatter kernel for calibration. A 1.0 cm wide picket fence test pattern was used to test the accuracy of the kernel. Using the deconvolution method with the calculated dose kernels, the measurements from the flat panel EPID show improved agreement with the films.
4
Lachaîne, Martin. "Monte Carlo optimization of a metalamorphous-selenium portal imager." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27539.
Повний текст джерелаАнотація:
An amorphous-Selenium (a-Se) based portal detector, which uses the metal substrate as a conversion plate, is studied using Monte Carlo techniques. The optimal thickness and material of the metal plate and a-Se thicknesses are investigated by modelling dose deposition in the a-Se layer for a 6 MV exit beam. Simulations of Detective Quantum Efficiency DQE(f) show that although DQE(0) increases with metal thickness up to $d sb{max},$ there is a cross-over near 1 cycle/mm which indicates that smaller metal thicknesses are more useful to visualize edges and small objects. A similar cross-over, though not as prominent, is also observed with constant metal thickness while varying a-Se thickness. Tungsten front plates are shown be optimal in terms of DQE for the plates under investigation. The effect of the scattered beam, described by the Scatter Fraction SF and Scatter-to-Primary Ratio SPR, is also modelled to ensure that the front-plate, which also acts as a scatter-rejection tool, satisfactorily filters out the scatter component. The SF is measured experimentally with a prototype imager for four metal plate/a-Se combinations and agrees with the Monte Carlo results within experimental uncertainties.
5
Lynde, Clément. "Développement d'un imageur neutron portable." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAE006/document.
Повний текст джерелаАнотація:
Le sujet de la thèse vise à développer un imageur neutron portable présentant des performances de détection compatibles avec les besoins de la recherche et de l’industrie nucléaire, notamment ceux du démantèlement. Cette thèse se décompose en trois axes principaux de recherche, précédés d’une phase de recherche bibliographique. Suite à cette dernière, l’approche de localisation retenue est l‘imagerie de neutrons rapides par encodage spatial. Les détecteurs de neutrons ont été étudiés et plusieurs choix, adaptés à cette problématique, ont été retenus pour la suite de l’étude. Le premier axe est consacré aux études sur le développement d’un détecteur de neutrons sensible à la position. Le deuxième axe est lié à la conception et au prototypage d’un imageur neutronique, se reposant sur un masque codé et un détecteur Timepix modifié par une couche de paraffine. Le dernier axe concerne le déploiement et la caractérisation expérimentale de ce prototypeThe subject of the thesis aims at developing a portable neutron imager with detection performance compatible with the needs of the nuclear research and industry, in particular those of decommissioning. This thesis is divided into three main areas of research, preceded by a bibliographic research phase. Following the latter, the localization approach adopted is spatial encoding fast neutron imaging. Neutron detectors were studied and several choices adapted to this challenge were selected for the continuation of the study. The first axis is dedicated to the studies on the development of a position-sensitive neutron detector. The second axis is related to the design and prototyping of a portable neutron imager, based on a coded aperture and a Timepix detector enhanced with a paraffin layer. The last axis concerns the deployment and experimental characterization of this prototype
6
Lachaîne, Martin. "Monte Carlo optimization of a metal/amorphous-selenium portal imager." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ37138.pdf.
Повний текст джерела
7
Jacoby, Grant A. "A metric model for Intranet portal business requirements." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FJacoby%5FPhD.pdf.
Повний текст джерела
8
Lachane, Martin. "Portal imaging with a direct-detection active matrix flat panel imager." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38070.
Повний текст джерелаАнотація:
The problem of charge creation by x-rays in amorphous selenium (a-Se) is studied. A quantitative theory is developed which includes collective and single electron-hole pair excitations by a passing electron. This theory is incorporated into a Monte Carlo code to calculate track structures in a-Se. The initial positions of the electron-hole pairs along these tracks are used to study the fraction of pairs which recombine versus incident x-ray energy and applied electric field. The experimentally-observed energy dependence of recombination is attributed to a spur size which is dependent on the velocity of the ionizing electrons. The theory and simulations agree with available experimental data in the energy range from 20 keV to 10 MeV.The use of an a-Se based direct-detection active matrix flat-panel imager (AMFPI) is explored at megavoltage energies for use in the verification of radiotherapy treatments. As with most other megavoltage detectors, a metal front plate is used to reduce patient scatter and to act as a buildup layer. The Modulation Transfer Function (MTF), Noise Power Spectrum (NPS), and Detective Quantum Efficiency (DQE) are measured. The DQE for the direct detection AMFPI is compared with the published DQE of an indirect detection AMFPI for portal imaging. The direct detector has a lower DQE at zero frequency, but there is a cross-over at approximately 0.3 cycles/mm after which it has a higher DQE.
A theoretical expression for the DQE of medical imaging detectors with non-elementary cascade stages is derived. This formalism can be used in conjunction with Monte Carlo techniques to evaluate the DQE of megavoltage imaging detectors. The predictions of the theory agree with the experimental DQE results for the direct-detection AMFPI and also for published results for the DQE of both a metal/phosphor detector and an indirect-detection AMFPI.
The effect of scatter on image quality is modeled in terms of the scatter fraction (SF) and scatter-to-primary ratio (SPR) using Monte Carlo techniques. To validate these simulations, the SF is measured experimentally using a prototype a-Se detector which uses an electrostatic probe to measure the a-Se surface potential. The simulations are used, along with the DQE simulations, to study the effect of metal/a-Se or metal/phosphor thicknesses on image quality in direct and indirect AMFPIs at megavoltage energies. It is found that for a-Se or phosphor thicknesses less than about 300 mum, a front plate of about 1 mm copper is optimal whereas for larger a-Se/phosphor thicknesses a front plate of about 0.4 mm may in some situations lead to better image quality.
9
Rader, Neil Christopher. "Development of a Civil Engineer Corps community portal prototype." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Jun%5FRader.pdf.
Повний текст джерела
10
Watanabe, Érika Yumi. "Avaliação do dispositivo eletrônico de imagem portal \"Portal Dosimetry\" no controle de qualidade de radioterapia de intensidade modulada." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-08082011-110213/.
Повний текст джерелаАнотація:
No presente trabalho serão apresentados testes de comissionamento e de avaliação da utilização do portal dosimetry, da Varian, no controle de qualidade dos planejamentos de radioterapia de intensidade modulada. Os testes de comissionamento foram realizados para caracterizar o portal dosimetry em termos dosimétricos e para avaliar a sua possível aplicação em radioterapia. Esses testes demonstraram que o portal dosimetry possui todas as características necessárias para ser utilizado em dosimetria na radioterapia tais como linearidade da resposta com a dose, independência com a taxa de dose, reprodutibilidade, dentre outras. A avaliação da utilização do portal dosimetry no controle de qualidade de IMRT foi realizada em duas etapas: avaliação da capacidade do dispositivo em detectar erros propositalmente introduzidos em fluências simples e em fluências complexas. Foram introduzidos erros de magnitude conhecida em áreas determinadas das fluências e foi realizado o controle de qualidade dessas fluências com o portal dosimetry e com mais três sistemas dosimétricos: câmara de ionização, filme e matriz de câmaras de ionização. Os dados obtidos com o portal foram comparados com os dos outros dispositivos e todos foram capazes de identificar os erros introduzidos de maneira satisfatória, sendo os valores, normalizados para a fluência original, obtidos com o dosímetro portal indênticos aos da câmara de ionização e aos da matriz de câmaras de ionização (seven29) e diferindo em até 2% dos valores obtidos com os filmes. As fluências medidas com o portal dosimetry foram avaliadas em termos quantitativos e qualitativos. Os índices da função gama fornecidos pelo software de análise do portal dosimetry não apresentaram regras definidas de comportamento em relação aos erros introduzidos e por essa razão a análise qualitativa se mostrou indispensável nos casos avaliados.In this paper we present commissioning testing and evaluation of the use of Varians portal dosimetry in the quality assurance of intensity-modulated radiotherapy. The commissioning tests were performed to characterize the portal dosimetry in terms dosimetric and to assess the its possible application in radiotherapy. These tests demonstrated that portal dosimetry has all the characteristics to be used for dosimetry in radiotherapy such as linear response with dose, the independence of dose rate, reproducibility, and others. The evaluation of the use of portal dosimetry in quality control of IMRT was performed in two steps: assessing the ability of the device to detect errors deliberately introduced in simple and complex fluences. Errors of known magnitude were introduced in certain areas of fluences and was carried out quality control of these fluences with portal dosimetry and three dosimetric systems: ionization chamber, film and array of ionization chambers. The data obtained from the portal were compared with those of other devices and all were able to identify errors introduced satisfactorily, the values, normalized to the original fluence, obtained with the portal dosimetry were similar to the ionization chamber and the array of ion chambers (seven29) and differing in up to 2% of the values obtained with the films. The fluences measured with the portal dosimetry were evaluated both quantitatively and qualitatively. The index of the gamma function provided by software analysis of portal dosimetry showed no defined rules of behavior in relation to the errors introduced and for this reason the qualitative analysis has proved indispensable in cases evaluated.
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WATANABE, ERIKA Y. "Avaliacao do dispositivo eletronico de imagem portal 'portal dosimetry' no controle de qualidade de radioterapia de intensidade modulada." reponame:Repositório Institucional do IPEN, 2010. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9564.
Повний текст джерелаАнотація:
Made available in DSpace on 2014-10-09T12:28:05Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:01:20Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Wang, Hui 1964. "Development of a portal imager and of tools for radiation treatment verification." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40463.
Повний текст джерелаАнотація:
A prototype electrostatic imager has been developed for megavoltage portal imaging in radiation therapy. The imager utilizes amorphous selenium (a-Se) with a front metal plate as the imager receptor and a high resolution voltmeter probe for image readout. Imaging characteristics of a-Se have been investigated theoretically through Monte Carlo simulations, and experimentally by measuring radiation discharging curves and phantom tests. The results of this study have shown that the prototype imager has high sensitivity, good spatial resolution and low noise level. Our study also reveals the potential of electrostatic imaging with metal/a-Se in megavoltage imaging.Two computer algorithms have also been developed for automatic segmentation and contrast-enhancement of digital portal images, and for radiation field shape verification. Based on a priori knowledge of the properties of portal images, the segmentation and contrast-enhancement algorithm employs multiple criteria and dynamic reasoning to achieve optimal segmentations of individual images, and has been proved to be accurate, robust and fast. The algorithm for radiation field shape verification is an adaptation of the chamfer matching technique to a specific application: matching closed contours. By incorporating geometric features of the radiation field and using a simple minimization method which is more specific to this task, the algorithm appears to be able to improve the matching results of the standard method.
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Melo, Eliana Virgínia Vieira de. "Persuasão nas imagens generificadas nos jogos online infantis do portal Clickjogos." reponame:Repositório Institucional da UFSC, 2015. https://repositorio.ufsc.br/xmlui/handle/123456789/160712.
Повний текст джерелаАнотація:
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação Interdisciplinar em Ciências Humanas, Florianópolis, 2015.Made available in DSpace on 2016-04-19T04:12:25Z (GMT). No. of bitstreams: 1 337747.pdf: 7246899 bytes, checksum: 341fa5198adffcf3b83304b5eba0d89d (MD5) Previous issue date: 2015
Este trabalho se dedica a análises das linguagens gráficas pictóricas utilizadas nas imagens ilustrativas dos cenários dos jogos online infantis no portal ClickJogos. Atualmente, é um dos websites brasileiros mais requisitados pelas crianças e adolescentes e é especializado na disponibilização de jogos digitais na área de mídia de entretenimento virtual na Internet. As análises encontram-se embasadas, principalmente, nas teorias de gênero, na historicização dos movimentos feministas em relação às novas tecnologias, na revisão dos estudos referentes ao entretenimento infantil virtual e nos modos de persuasão visual nas imagens, remetendo aos estudos da retórica visual. Com estes aportes teóricos, fizemos uso de algumas figuras retóricas visuais como parâmetros e instrumentos de análise, com o intuito maior de evidenciar as práticas dos usos de gênero. Identificamos simetrias e assimetrias nas relações de gênero nas imagens gráficas pictóricas, que possibilitam a interação das crianças, através da jogabilidade, dos modos de jogo e das ações dentro dos jogos online infantis. Levamos em conta os códigos visuais morfológicos, cromáticos e tipográficos que compõem as imagens ilustrativas dos cenários e personagens dos jogos. Como resultado, encontramos ocorrências de diferenças acentuadas no tratamento destes códigos imagéticos dos jogos prescritos ?para meninas? pelo portal ClickJogos em relação aos jogos sem prescrição, considerados aqui como ?universais?. Neste estudo, que contribui com áreas de Ciências Humanas e Design, fica constatada a exigência de atenção especial, por parte de profissionais nas áreas de produção de jogos digitais infantis, em relação às projetações de linguagens gráficas pictóricas que contemplem as simetrias de gênero, promovendo entendimentos seminais destas questões desde a infância. Sem dúvida, os jogos digitais podem ser instrumentos poderosos de informação para a disseminação das questões de gênero, e de minimização de preconceitos.
Abstract : This paper aims at analyzing Pictorial and Graphic Languages used as illustrations for children?s online game scenarios on ClickJogos website. Nowadays, this website is one of Brazilian?s favorite and specialized in making digital games available, each time more requested by children and teenagers when it comes to virtual entertainment media in the Internet. The analysis are mainly supported by gender theories, historicizing feminist movements in relation to new technologies, reviewing studies concerned with children virtual entertainment and visual persuasion in images, which is connected with visual rhetoric studies. Based on this theoretical framework, we made use of some visual rhetoric images as parameters and analysis tools in order to make gender practices visible. Then we identified gender symmetries and asymmetries in the graphic images that allow children?s interaction with the game and its playability, the ways the game is played and actions within the children?s online games. We considered the morphological graphic indexes, chromatic and typographic that form the scenario?s and the character?s illustrations in the games. As results we have evidence that there are accentuated differences in the treatment for imagery codes in games prescribed as ?for girl? by the ClickJogos website in relation to games that have no gender indication, considered as ?universal?. In this paper, which contributes to areas such as Human Sciences and Design, we emphasize the special attention on the children?s digital online games production end and by the professionals in relation to Pictorial Graphic specific Languages that allow for gender symmetries, promoting inspiring understanding of such matters every since childhood. No doubt, digital online games may be powerful information tools in the work of disseminating gender matters and minimizing bias.
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Sirois, Luc M. "3-D automatic anatomy-based image registration in portal imaging." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0025/MQ50880.pdf.
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Pedrosa, Micael Cardoso. "A web portal for Portuguese brain imaging network." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/2163.
Повний текст джерелаАнотація:
Mestrado em Engenharia de Computadores e TelemáticaA Imagiologia Cerebral (IC) está na fronteira entre a neurologia, engenharia e física. écnicas de imagens médicas multimodais, tais como a Ressonância Magnética (MRI e fMRI) e Espectroscopia (MRS), Tomografia Computadorizada por Emissão de Fotões/Positrões (SPECT/PET), entre outros, são emergentes ferramentas de pesquisa médica que pode fornecer informações valiosas para o diagnóstico de doenças do cérebro. Eletroencefalograma de alta resolução (HR-EEG), técnicas para sincronizar e fundir seus resultados de análise e várias técnicas de imagem são também parte de IC. Em Portugal, dado o facto que a maioria das áreas relacionadas com IC (por exemplo, medicina, engenharia ou física) são assuntos de investigação em muitos grupos de P&D, um consórcio de universidades de Aveiro, Coimbra, Minho e Porto criou a Rede Nacional de Imagiologia Funcional Cerebral (RNIFC). A RNIFC é uma associação sem fins lucrativos que foi formalizada e assinada em fevereiro de 2009. Actualmente, com o suporte de sistemas digitais para armazenar imagens médicas, é possível partilhar dados entre essas instituições para melhorar o diagnóstico, e permitir investigações entre a comunidade médica de diferentes instituições. O principal objectivo desta dissertação é descrever a implementação dos serviços de sistemas de informação essenciais para a Brain Imaging Network (BIN) que suportam actualmente o RNIFC acessível através do Portal BIN, o principal ponto de entrada para a BING. O Portal BIN permite aos pesquisadores na comunidade BING espalhadas pelo país e no estrangeiro, quer para solicitar o acesso a instrumentos científicos ou para recuperar os seus casos e executar as suas análises. ABSTRACT: Brain Imaging is in the frontier between neurology, engineering and physics. Multimodal medical imaging techniques, such as Magnetic Resonance Imaging (MRI and fMRI) and Spectroscopy (MRS), Single Photon/Positron Emitting Tomography (SPECT/PET) among others, are emergent medical research tools that can provide valuable information for diagnosis of brain diseases. High-resolution electroencephalogram (HR-EEG), techniques for synchronizing and fuse its analysis results and several imaging techniques are also part of BI. In Portugal, given fact that most of the BI related areas (e.g. medical, engineering or physics) are subjects of research in many R&D groups, a consortium of the universities of Aveiro, Coimbra, Minho and Porto created the National Functional Brain Imaging Network (RNIFC). The RNIFC is a non-profitable association that was formalized and signed in February 2009. Currently, with the support of digital systems to store medical images, it is possible to share data among these institutions to improve diagnosis, and allow investigations by the medical community among different institutions. The main objective of this thesis is to describe the implementation of the essential Brain Imaging Network (BIN) information systems services that currently support the RNIFC accessible through the BIN Portal, the main entry point for the BING. BIN Portal enables researchers in the BING community scattered along the country and abroad either to apply for access to the scientific instruments or to retrieve their cases and run their analysis.
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Liu, Xindi. "The Ashes and the Portal: An immersive stereoscopic experience on Cyclorama." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/92801.
Повний текст джерелаАнотація:
the Ashes and the Portal is an immersive stereoscopic animated short capturing the burned library after a fire disaster at Mzuzu University, Malawi, Africa, and it also witnesses the new design of the library from Virginia Tech architecture students. This animated short recreates the burned library and presents the new library design with photo-real image sequences which can immersively bring the audiences onto the site. The Ashes and the Portal utilizes the Cyclorama system, which is a 32 feet diameter and 16 feet tall cylindrical screen with four projectors that can display visual content. The surrounding panels with rendered footage could provide an immersive experience within this semi-public space. This is a collaboration project between the School of Visual Arts and the School of Architecture + Design, also with technical support from the Institute for Creativity, Arts, and Technology. This project explores the potential use of Cyclorama system as a platform for CG works, especially for stereoscopic animation.Master of Fine Arts
The Ashes and The Portal is a computer generated animation tells a story about burned library at Mzuzu University, Malawi, Africa and a new library design from Virginia Tech architecture students. Audience is required to wear a pair of 3D goggles to view the animation inside a giant curved screen which is surrounding the viewer. The photo-real footage of burned library and new library design can visually bring audiences onto the site and provide an immersive experience. This project is a collaboration project between the School of Visual Arts and the School of Architecture + Design, also with technical support from the Institute for Creativity, Arts, and Technology. This is an educational project that explores the potential use of the Cyclorama system as a platform for computer generated media works, especially for stereoscopic animation.
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Amsden, Saundra L. "Web portal design, execution and sustainability for Naval Websites and Web services." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FAmsden.pdf.
Повний текст джерелаАнотація:
Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 2003.Thesis advisor(s): Don Brutzman, Curt Blair, Barb Helfer. Includes bibliographical references (p. 95-99). Also available online.
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Mosleh-Shirazi, Mohammad Amin. "A combined 3D megavoltage CT scanner and portal imager for treatment verification in radiotherapy." Thesis, Institute of Cancer Research (University Of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267840.
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Petersson, Anton. "Fast complex transformative portals." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3566.
Повний текст джерелаАнотація:
In this thesis an image-space and geometry hybrid algorithm for portal rendering is con- structed and evaluated in terms of correctness and performance. A number of tests are de ned and out of these three are selected and executed. Based on the results of these tests, the con- clusion is that a hybrid approach to portal rendering is a valid option for increasing the speed without sacri cing the correctness of an image-space portal rendering algorithm.
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MOURA, Francisco Tigre. "A formação da imagem de destinações turísticas na Web : o estudo do Portal visiteportodegalinhas.com." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/640.
Повний текст джерелаАнотація:
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Previous issue date: 2008Universidade Federal de Pernambuco
Esta dissertação teve como objetivo principal investigar de que modo o gerenciamento dos elementos de um website oficial de uma destinação turística se relaciona com a formação de uma imagem positiva da localidade, na perspectiva do consumidor. Primeiramente foi elaborada uma revisão teórica envolvendo a imagem em marketing, o estudo da imagem na internet, a imagem no turismo e o desenvolvimento de websites para a formação da imagem. A metodologia, de caráter exploratório-descritivo, realizou-se em duas fases, sendo a primeira qualitativa e a segunda quantitativa, onde se investigou o portal www.visiteportodegalinhas.com. Na primeira fase, foram desenvolvidas pesquisas bibliográficas e entrevistas pessoais semi-estruturadas. A segunda fase caracterizou-se pelo desenvolvimento de um survey com estudantes de graduação. Utilizou-se a escala de mensuração da imagem de destinações turísticas proposta por Echtner e Ricthie (1991) na elaboração do instrumento de coleta de dados. Nas análises, foram empregadas técnicas estatísticas descritivas e teste de hipóteses (MALHOTRA, 2006). Os resultados indicaram que a visitação a sites oficiais de turismo previamente a ida ao local, se relaciona positivamente com a formação da imagem que os consumidores possuem destas localidades, e que é possível transmitir uma imagem desejada de um destino turístico através do gerenciamento dos elementos do website da destinação turística. De modo geral, pode-se afirmar que os websites de destinações turísticas devem ser tratados como elementos estratégicos por parte dos gestores
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Tollefsen, Cristina Dawn Spanu. "Comparison of video and CCD cameras in online portal imagers calibrated for dosimetry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ57587.pdf.
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Husberg, Björn. "A Portable DARC Fax Service." Thesis, Linköping University, Department of Electrical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1373.
Повний текст джерелаАнотація:
DARC is a technique for data broadcasting over the FM radio network. Sectra Wireless Technologies AB has developed a handheld DARC receiver known as the Sectra CitySurfer. The CitySurfer is equipped with a high-resolution display along with buttons and a joystick that allows the user to view and navigate through various types of information received over DARC.
Sectra Wireless Technologies AB has, among other services, also developed a paging system that enables personal message transmission over DARC. The background of this thesis is a wish to be able to send fax documents using the paging system and to be able to view received fax documents in the CitySurfer.
The presented solution is a central PC-based fax server. The fax server is responsible for receiving standard fax transmissions and converting the fax documents before redirecting them to the right receiver in the DARC network. The topics discussed in this thesis are fax document routing, fax document conversion and fax server system design.
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Wu, Peter A. "A methodology for the development of secure vertical web portals." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FWu.pdf.
Повний текст джерелаАнотація:
Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 2002.Thesis advisor(s): Neil C. Rowe, Xavier Maruyama. Includes bibliographical references (p. 105-109). Also available online.
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McCurdy, Boyd Matthew Clark. "Development of a portal dose image prediction algorithm for arbitrary detector systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ62655.pdf.
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Sperling, Nicholas Niven. "A Novel Algorithm for the Reconstruction of an Entrance Beam Fluence from Treatment Exit Patient Portal Dosimetry Images." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1384521982.
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Azoulay, Michel M. "Aural stealth for night vision portable imagers." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6380.
Повний текст джерелаАнотація:
Modern tactics for carrying out military and antiterrorist operations calls for the development of a new generation of enhanced portable infrared imagers. The high performance of these imagers relies on the focal plane arrays, which are maintained at cryogenic temperatures using rotary Stirling cryogenic engines. These engines are known as powerful sources of wideband vibration export. For the sake of weight and compactness, the enclosure of the above imager is usually designed in the form of a light metal thin-walled shell, accommodating a directly mounted Infrared Detector Dewar Cooler Assembly. The operation of the device typically leads to an excitation of the inherently lightly damped structural resonances and therefore, to a radiation of the specific acoustic signature capable of compromising the aural stealth of the IR imager. Such a noisy IR imager may be detected from quite a long distance using enhanced sniper detection equipment or even aurally spotted when used in a close proximity to the target. Numerous efforts were taken towards achieving the desired inaudibility level, apparently becoming one of a crucial figure of merit characterizing the portable IR imager. However, even the best examples of modern should-be silent imagers are quite audible from as far as 50 meters. The presented research intends to improve the aural stealth of the portable IR imager by using three different approaches: First, by compliantly mounting the Infrared Detector Dewar Cooler Assembly where the stiffness and damping of the vibration protective pad are optimized for the best acoustical performance without developing excessive line of sight jitter. Secondly, by using the concept of the weak radiator to reshape the enclosure mode shapes, and finally developing a multi-modal distributed dynamic absorber (MMDA) to enhance the absorption of the vibrating structure. The multi-modal characteristic of such a dynamic absorber makes it highly dynamically reactive through a wide frequency range (20 kHz) of excitation. It will be shown that incorporating a MMDA into the vibrating structure will result in ultra range vibration attenuation, making the IR aurally silent.
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Sheen, Timothy M. "Tools for portable parallel image processing." Thesis, University of Aberdeen, 1999. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU112832.
Повний текст джерелаАнотація:
The computational demands of real-time image processing often dictate the use of techniques such as parallel processing to meet required performance. This thesis considers a range of technology which may be used to accelerate image processing operations. An occam compiler is ported to a PowerPC based parallel computer. A multiprocessor configuration tool and Run Time System is developed, allowing occam programs to be distributed over an arbitrary sized network of PowerPC microprocessors. Code optimization techniques for image processing operations are investigated, with the development of a post-compilation code optimizer. The optimizer provides performance increases between 37% and 450% for a variety of image processing algorithms. The applicability of these tools is demonstrated with two image processing applications, micro-biological rapid imaging and sediment texture analysis. Edge detection, region merging and shape analysis algorithms are discussed in the context of the applications. The image processing algorithms are implemented in occam and performance is compared on serial and parallel platforms. The algorithms are then ported to a hardware implementation in a custom computing device, based on a field programmable gate array (FPGA), using the Handel hardware compilation system. The issues involved with this porting are discussed, including the compromises which must be considered when designing for a size constrained hardware platform. Amongst the issues considered are restricted precision data, low level parallelism and algorithmic simplifications. To provide performance equivalent to the hardware, between 5 and 10 processors would be required on the parallel machine, with considerably greater cost, size and power consumption.
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Walton, Dean R. "Effect of slit scan imaging techniques on image quality on radiotherapy electronic portal imaging." Connect to full text in OhioLINK ETD Center, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=mco1217886133.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Toledo, 2008."In partial fulfillment of the requirements for the degree of Master of Science in Biomedical Sciences." Title from title page of PDF document. Bibliography: pages 67-72.
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Ribeiro, Leonardo Andrade. "Um portal de banco de imagens médicas distrubuído usando corba para integração de serviços de teleradiologia." Florianópolis, SC, 2002. http://repositorio.ufsc.br/xmlui/handle/123456789/83950.
Повний текст джерелаАнотація:
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.Made available in DSpace on 2012-10-20T04:54:46Z (GMT). No. of bitstreams: 1 208066.pdf: 638412 bytes, checksum: c762b70508aada6ed9a0a59748b8d2c9 (MD5)
A área do diagnóstico por imagem é um dos campos da medicina mais propensos a uso da Telemedicina, porque normalmente não existe a obrigação do contato direto com o paciente pelo radiologista responsável durante a elaboração do diagnóstico. A carência de especialistas em locais distantes de grandes centros urbanos faz da Telemedicina uma importante ferramenta para melhorar os serviços de atenção à saúde. Neste trabalho é apresentado um modelo baseado em uma abordagem federada chamo Portal de Teleradiologia, para a integração de bancos de imagens médicas DICOM distribuído geograficamente. O objetivo é prover uma visão única e transparente dos dados compartilhados sem sacrificar a autonomia dos sistemas integrantes ou interferir com operações locais. Um requisito obrigatório para sistemas desta natureza é a garantia de um contexto seguro para a execução das operações. O modelo proposto prevê também a identificação única de pacientes entre as diversas bases de dados através de técnicas de relacionamento de registros. Para a implementação do protótipo do sistema foi utilizada a tecnologia de objetos distribuídos através da arquitetura CORBA.
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Spampinato, Letizia. "Thermal monitoring of active volcanoes using portable infrared imagers." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609816.
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Walker, Justin A. "The Use of an On-Board MV Imager for Plan Verification of Intensity Modulated Radiation Therapy and Volumetrically Modulated Arc Therapy." University of Toledo Health Science Campus / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=mco1372701428.
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Taourel, Patrice. "Images et signaux du foie et de la circulation sanguine splanchnique chez l'homme." Tours, 1996. http://www.theses.fr/1996TOUR3308.
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Tavares, Enéias Farias. "As Portas da Percepção: Texto e Imagem nos Livros Iluminados de William Blake." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/3976.
Повний текст джерелаАнотація:
Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorEsta tese de doutorado propõe analisar a origem e a interpretação dos livros iluminados de William Blake. A produção do artista foi efetuada como um empreendimento técnico no qual texto e imagem eram gravados numa mesma chapa de impressão, para depois resultarem em diversas cópias impressas e finalizadas com aquarela. A fim de mapear as experimentações que culminaram na técnica de impressão iluminada, o primeiro capítulo discute a formação tripla de Blake como gravurista, poeta e pintor. O segundo analisa o poema narrativo e as ilustrações para Tiriel, livro que evidencia o primeiro esforço de Blake em unir texto e imagem. O terceiro, além de detalhar o método iluminado de impressão, discute o contexto de produção e as possíveis metas do seu autor ao empreender tal arte. O interlúdio apresenta uma discussão metodológica sobre o tipo de análise e conceituação crítica para o estudo de sua arte. Partindo dessa proposta, os capítulos seguintes objetivam uma interpretação dos primeiros livros iluminados de Blake. Os capítulos 4 e 5 discutem as Canções de Inocência e as Canções de Experiência, ao passo que o último se debruça sobre O Matrimônio de Céu e Inferno. Tais capítulos demonstram como, na criação do artista, texto e imagem mantêm uma dialógica relação de oposição e complementaridade que revela a meta do autor de fragilizar o discurso dualista de seu tempo, seja ele científico ou religioso, ao propor uma arte centrada na união de percepções físicas e mentais, visuais e textuais. O recorte metodológico prioriza na primeira parte desta tese uma discussão sobre o contexto cultural da arte de Blake e na segunda uma análise dos processos de leitura, observação e interpretação de seus livros.
Esta tese de doutorado propõe analisar a origem e a interpretação dos livros iluminados de William Blake. A produção do artista foi efetuada como um empreendimento técnico no qual texto e imagem eram gravados numa mesma chapa de impressão, para depois resultarem em diversas cópias impressas e finalizadas com aquarela. A fim de mapear as experimentações que culminaram na técnica de impressão iluminada, o primeiro capítulo discute a formação tripla de Blake como gravurista, poeta e pintor. O segundo analisa o poema narrativo e as ilustrações para Tiriel, livro que evidencia o primeiro esforço de Blake em unir texto e imagem. O terceiro, além de detalhar o método iluminado de impressão, discute o contexto de produção e as possíveis metas do seu autor ao empreender tal arte. O interlúdio apresenta uma discussão metodológica sobre o tipo de análise e conceituação crítica para o estudo de sua arte. Partindo dessa proposta, os capítulos seguintes objetivam uma interpretação dos primeiros livros iluminados de Blake. Os capítulos 4 e 5 discutem as Canções de Inocência e as Canções de Experiência, ao passo que o último se debruça sobre O Matrimônio de Céu e Inferno. Tais capítulos demonstram como, na criação do artista, texto e imagem mantêm uma dialógica relação de oposição e complementaridade que revela a meta do autor de fragilizar o discurso dualista de seu tempo, seja ele científico ou religioso, ao propor uma arte centrada na união de percepções físicas e mentais, visuais e textuais. O recorte metodológico prioriza na primeira parte desta tese uma discussão sobre o contexto cultural da arte de Blake e na segunda uma análise dos processos de leitura, observação e interpretação de seus livros.
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Morales, Vargas Alejandro. "Gestión y desarrollo del portal web del Instituto de la Comunicación e Imagen de la Universidad de Chile." Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/110795.
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Atwal, Parmveer Singh. "An electronic portal image-based monte carlo approach to in-vivo dosimetry for intensity modulated radiation therapy." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/13711.
Повний текст джерелаАнотація:
Radical radiotherapy aims to concurrently achieve high tumour control probability and low normal tissue complication probability. Intensity-modulated radiation therapy (IMRT) provides the highly localized radiation dose delivery necessary to reach this goal. As highly conformal techniques become more prevalent, the importance of determining, and accounting for, treatment-planning, patient-setup, and delivery errors, which result in discrepancies between the calculated and actual delivered dose, also increases. Accurate Monte Carlo-based modeling of the equipment overcomes some of these deficiencies. Unfortunately, some sources of delivery errors, such as mis-calibration of the beam-modulating system, cannot be easily incorporated in the model.
Use of the amorphous-silicon detector (or EPID, for Electronic Portal Imaging Device), available on many linear accelerators, provides a solution. We hypothesize that non-transit dose images from the EPID provide us with information regarding certain delivery errors. To obtain this information, we first capture non-transit EPID dose images of the treatment field. Next, removal of intra-EPID scatter via iterative Richardson-Lucy deconvolution converts the dose image to a fluence matrix. Projected back to the height of the beam-modulating system, this matrix can be used to modulate the statistical weight of photons in a phase-space file simulating the linear accelerator from the source to this height. The modulated phase-space can be used to run Monte Carlo calculations through simulated phantoms.
Assumptions regarding the EPID's electromechanical behaviour, as well as regarding beam divergence, were validated. This method was compared and validated against our centre's treatment planning system, for various configurations of the beam-modulating system, in two non-patient phantoms (water and anthropomorphic). The new procedure matched well with film measurements, consistently providing a higher percentage (~10%-15% higher) of pixels with Gamma-Dose (3mm Distance-To-Agreement, 3% Dose-Difference criteria) less than 1, versus the TPS-based dose distributions. This indicates that the EPID-based fluence is more accurate than the TPS-based fluence. This so-called MCEF (Monte Carlo with EPID-based Fluence) procedure can be extended by utilizing Cone-Beam CT (CBCT) to account for any setup errors or physiological changes in the patient. By coupling the EPID-based fluence with CBCT-based phantoms, we believe this method will accurately mimic true 3D in-vivo dosimetry.
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Chabert, Isabelle. "Développement et validation d’un modèle de sources virtuelles adapté à la prédiction d’images EPID pour le contrôle qualité des traitements de RCMI." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112016/document.
Повний текст джерелаАнотація:
L’essor des nouvelles techniques de traitement en radiothérapie externe a rendu nécessaire la mise en place de nouveaux contrôles qualité (CQ). Il est en effet capital de s’assurer que la dose délivrée au patient est bien conforme à celle qui lui a été prescrite. Les détecteurs EPID, initialement utilisés pour contrôler l’exactitude du positionnement du patient, sont de plus en plus employés pour vérifier la conformité du traitement. L’image qu’ils enregistrent au cours d’une irradiation peut par exemple être comparée à une image de référence, qui correspond à ce qui aurait été mesuré si le traitement s’était déroulé dans les conditions de sa planification. Le succès de ce CQ repose (1) sur la précision avec laquelle on peut prédire l’image EPID (ou portale) de référence et (2) sur les performances de l’outil de comparaison d’image utilisé. Nous avons étudié au cours de cette thèse ces deux points clés. Nous nous sommes tout d’abord tournés vers une méthode de prédiction d’images EPID haute résolution basée sur le couplage de simulations Monte-Carlo (MC) et de la technique de débruitage DGPLM. Pour la mettre en œuvre, nous avons modélisé un accélérateur linéaire d’électrons à usage médical (linac) dans le code MC PENELOPE et optimisé les paramètres de sa source d’électrons primaires pour des calculs de dose dans l’eau. L’analyse d’un fichier d’espace des phases (PSF) de 71 Go stocké sous le cône égalisateur nous a ensuite permis de développer un modèle de sources virtuelles (MSV) représenté par des histogrammes corrélés (environ 200 Mo). Ce nouveau MSV, plus compact que le PSF, est tout aussi précis pour les calculs de dose dans l’eau si son maillage est déterminé selon une méthode adaptative. La modélisation du détecteur EPID dans PENELOPE suggère que les hypothèses faites sur les propriétés de la tâche focale du linac sont trop simplistes et doivent être reconsidérées. L’évaluation du MSV pour la prédiction d’images EPID haute résolution a quant à elle conduit à d’excellents résultats. Une fois la chaine de prédiction de l’image portale de référence validée, nous l’avons utilisée pour détecter des irrégularités dans les traitements de RCMI. Dans une étude préliminaire, nous avons volontairement introduit des erreurs de traitement dans le calcul d’images EPID (dérive du faisceau d’irradiation, modification de la morphologie ou de la position du patient). Le γ-index traditionnellement utilisé en routine s’est avéré moins performant que le χ-index pour les détecter. Une étude plus approfondie aura pour objet de déterminer des seuils de détection d’erreurs en fonction de leur nature et d’éprouver les performances d’autres testsAdvanced techniques used in radiotherapy for cancer treatment, such as Intensity-Modulated Radiation Therapy (IMRT), require extensive verification procedures to ensure the correct dose delivery. Electronic Portal Imaging Devices (EPIDs) are widely used for quality assurance in radiotherapy, and also for dosimetric verifications. For this latter application, the images obtained during the treatment session can be compared to a pre-calculated reference image in order to highlight dose delivery errors. The quality control performance depends (1) on the accuracy of the pre-calculated reference image (2) on the ability of the tool used to compare images to detect errors. These two key points were studied during this PhD work. We chose to use a Monte Carlo (MC)-based method developed in the laboratory and based on the DPGLM (Dirichlet process generalized linear model) denoising technique to predict high-resolution reference images. A model of the studied linear accelerator (linac Synergy, Elekta, Crawley, UK) was first developed using the PENELOPE MC codes, and then commissioned using measurements acquired in the Hôpital Nord of Marseille. A 71 Go phase space file (PSF) stored under the flattening filter was then analyzed to build a new kind of virtual source model based on correlated histograms (200 Mo). This new and compact VSM is as much accurate as the PSF to calculate dose distributions in water if histogram sampling is based on adaptive method. The associated EPID modelling in PENELOPE suggests that hypothesis about linac primary source were too simple and should be reconsidered. The use of the VSM to predict high-resolution portal images however led to excellent results. The VSM associated to the linac and EPID MC models were used to detect errors in IMRT treatment plans. A preliminary study was conducted introducing on purpose treatment errors in portal image calculations (primary source parameters, phantom position and morphology changes). The γ-index commonly used in clinical routine appears to be less effective than the χ-index. A future in-depth study will be dedicated to determine error detection threshold according to their nature and to evaluate other comparison test robustness. The developed portal image prediction method associated to robust analysis tools will then constitute an adapted way to assure treatment quality control
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Clement, Jeffrey. "The spillable environment : expanding a handheld device's screen real estate and interactive capabilities /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2066.pdf.
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McCowan, Peter Michael. "in vivo patient dose verification of volumetric modulated arc therapy including stereotactic body radiation treatment applications using portal dose images." Medical Physics, 2015. http://hdl.handle.net/1993/31120.
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The complexity of radiation therapy delivery has increased over the years due to advancements in computing and technical innovation. A system of dose delivery verification has the potential to catch treatment errors and therefore improve patient safety. The goal of this thesis was to create a portal image-based in vivo dose reconstruction model for volumetric modulated arc therapy (VMAT) deliveries, specifically for stereotactic body radiation therapy (SBRT). This model-based approach should be robust and feasible within a clinical setting. VMAT involves the modulation of dose rate, gantry speed, and aperture shaping while the treatment gantry (i.e., x-ray beam) rotates about the patient. In this work, portal images were acquired using an amorphous silicon electronic portal imaging device (a-Si EPID).
A geometrical characterization of the linear accelerator (linac) during VMAT delivery was performed. An angle adjustment method was determined which improves each EPID’s angular accuracy to within ±1° of the true physical angle.
SBRT delivers large doses over fewer fractions than conventional radiotherapy, therefore, any error during an SBRT delivery will have a greater impact on the patient. In this work, a robust, model-based SBRT-VMAT dose reconstruction verification system using EPID images was developed. The model was determined to be clinically feasible.
The accuracy of a 3D in vivo dose reconstruction, using all the EPID images acquired during treatment, is sensitive to the chosen frame averaging per EPID image: the greater the frame averaging, the larger the reconstruction error. Optimization of the EPID frame averaging number as a function of average linac gantry speed and dose per fraction were determined.
The EPID-based in vivo dose reconstruction model for SBRT-VMAT developed here was determined to be robust, accurate, and clinically feasible as long as adjustments were made in order to correct for EPID image geometrical errors and frame-averaging errors.May 2016
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Boissard, Philippe. "Dosimétrie in vivo en radiothérapie externe avec imageurs portals au silicum amorphe : de la méthode à la validation clinique." Toulouse 3, 2012. http://thesesups.ups-tlse.fr/1676/.
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La dosimétrie in vivo en transmission réalisée avec les imageurs portals apparait être une alternative intéressante pour la réalisation de la dosimétrie in vivo en Radiothérapie externe. Une nouvelle méthode basée sur des fonctions de Rapport Tissue Maximum finit (RTMf) et sur une séparation Primaire / Diffusée est proposée. La dose dans le patient peut alors être estimée à partir du signal transmis mesuré pendant le traitement. 46 configurations test réalisées à l'aide de fantômes d'eau solide ont été proposées pour réaliser l'évaluation globale de la méthode. En outre, une étude clinique de validation a été conduite pour 494 patients. Les images portals ont été acquises à l'aide d'imageur portals au silicium amorphe montés sur des accélérateur Clinacs Varian(tm). La dose dans le patient est calculée par rétroprojection de la dose portal à l'aide du logiciel EPIgray(tm) (logiciel développé en collaboration avec la société DOSIsoft(tm)) et est comparée à celle planifiée à l'aide logiciel Eclipse Varian(tm) (algorithme Pencil Beam). Les écarts entre les doses planifiées et les dose mesurées sont reportés pour chaque point d'intérêt. Les résultats sont dans les niveaux de tolérances habituels de la dosimétrie in vivo (moyenne=0. 7% 1s= 2. 7% pour les mesures sur fantômes; moyenne =-0. 6% 1s= 2. 8% pour les mesures in vivo sur patients). Pour conclure, la dosimétrie in vivo en transmission est facile à utiliser en conditions de routine clinique (pas de temps additionnels lors du traitement). En utilisant la méthode proposée, la dose peut être calculée en tous points dans le patient. La précision des résultats est plus qu'acceptable pour le cadre de la dosimétrie in vivoTransit dosimetry performed with Electronic Portal Imaging Devices (EPIDs) appears as an interesting alternative for in vivo dose verification for patients receiving external Radiotherapy. A new method based on a transit Tissue Maximum Ratio (TMRt) and Primary/Scatter separation is proposed. The dose inside the patient could be estimated from the transmitted signal measured during irradiation. 46 test cases were defined, using solid water phantoms, for the overall method assessment. Moreover, a clinical study was driven for 494 patients. Portal Images are acquired using a-Si EPID mounted on 4 Varian Clinacs(tm). The dose in the patient is estimated from the back projection of the portal dose with EPIgray(tm) (software developed in a partnership with DOSIsoft(tm)) and compared with calculated data (Varian Eclipse(tm) software using pencil beam algorithm). Deviations between stated and measured doses are reported for each point of interest. The results are within the accepted tolerance of classical in vivo dosimetry (mean=0. 7% 1SD= 2. 7% for in-phantom dose verifications; mean =-0. 6% 1SD= 2. 8% for in vivo dose verifications). To conclude, transit dosimetry is easy to use systematically in clinical routine (no additional time for data acquisition). Using this method, the in vivo dose can be computed at any point. The accuracy of this method was more than acceptable for in vivo purpose
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Du, Ruixiang. "An Intelligent Portable Aerial Surveillance System: Modeling and Image Stitching." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-theses/859.
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"Unmanned Aerial Vehicles (UAVs) have been widely used in modern warfare for surveillance, reconnaissance and even attack missions. They can provide valuable battlefield information and accomplish dangerous tasks with minimal risk of loss of lives and personal injuries. However, existing UAV systems are far from perfect to meet all possible situations. One of the most notable situations is the support for individual troops. Besides the incapability to always provide images in desired resolution, currently available systems are either too expensive for large-scale deployment or too heavy and complex for a single solder. Intelligent Portable Aerial Surveillance System (IPASS), sponsored by the Air Force Research Laboratory (AFRL), is aimed at developing a low-cost, light-weight unmanned aerial vehicle that can provide sufficient battlefield intelligence for individual troops. The main contributions of this thesis are two-fold (1) the development and verification of a model-based flight simulation for the aircraft, (2) comparison of image stitching techniques to provide a comprehensive aerial surveillance information from multiple vision. To assist with the design and control of the aircraft, dynamical models are established at different complexity levels. Simulations with these models are implemented in Matlab to study the dynamical characteristics of the aircraft. Aerial images acquired from the three onboard cameras are processed after getting the flying platform built. How a particular image is formed from a camera and the general pipeline of the feature-based image stitching method are first introduced in the thesis. To better satisfy the needs of this application, a homography-based stitching method is studied. This method can greatly reduce computation time with very little compromise in the quality of the panorama, which makes real-time video display of the surroundings on the ground station possible. By implementing both of the methods for image stitching using OpenCV, a quantitative comparison in the performance is accomplished."
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Le, Luel Nathalie Barral i. Altet Xavier. "Le portail Saint-Ursin de Bourges recherches sur l'iconographie profane en façade des églises romanes /." Rennes : Université Rennes 2, 2009. http://theses.scdbases.uhb.fr:8000/theseLeLueldiffusable.pdf.
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Saussard, Romain. "Méthodologies et outils de portage d’algorithmes de traitement d’images sur cibles hardware mixte." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS176/document.
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Les constructeurs automobiles proposent de plus en plus des systèmes d'aide à la conduite, en anglais Advanced Driver Assistance Systems (ADAS), utilisant des caméras et des algorithmes de traitement d'images. Pour embarquer des applications ADAS, les fondeurs proposent des architectures embarquées hétérogènes. Ces Systems-on-Chip (SoCs) intègrent sur la même puce plusieurs processeurs de différentes natures. Cependant, avec leur complexité croissante, il devient de plus en plus difficile pour un industriel automobile de choisir un SoC qui puisse exécuter une application ADAS donnée avec le respect des contraintes temps-réel. De plus le caractère hétérogène amène une nouvelle problématique : la répartition des charges de calcul entre les différents processeurs du même SoC.Pour répondre à cette problématique, nous avons défini au cours de cette thèse une méthodologie globale de l’analyse de l'embarquabilité d'algorithmes de traitement d'images pour une exécution temps-réel. Cette méthodologie permet d'estimer l'embarquabilité d'un algorithme de traitement d'images sur plusieurs SoCs hétérogènes en explorant automatiquement les différentes répartitions de charge de calcul possibles. Elle est basée sur trois contributions majeures : la modélisation d'un algorithme et ses contraintes temps-réel, la caractérisation d'un SoC hétérogène et une méthode de prédiction de performances multi-architectureCar manufacturers increasingly provide Advanced Driver Assistance Systems (ADAS) based on cameras and image processing algorithms. To embed ADAS applications, semiconductor companies propose heterogeneous architectures. These Systems-on-Chip (SoCs) are composed of several processors with different capabilities on the same chip. However, with the increasing complexity of such systems, it becomes more and more difficult for an automotive actor to chose a SoC which can execute a given ADAS application while meeting real-time constraints. In addition, embedding algorithms on this type of hardware is not trivial: one needs to determine how to spread the computational load between the different processors, in others words the mapping of the computational load.In response to this issue, we defined during this thesis a global methodology to study the embeddability of image processing algorithms for real-time execution. This methodology predicts the embeddability of a given image processing algorithm on several heterogeneous SoCs by automatically exploring the possible mapping. It is based on three major contributions: the modeling of an algorithm and its real-time constraints, the characterization of a heterogeneous SoC, and a performance prediction approach which can address different types of architectures
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Rosa, Paulo Cezar. "Comunicação, Valores Comunitários e Sustentabilidade: os portais da UMESP, FEI e FSA." Universidade Metodista de São Paulo, 2009. http://tede.metodista.br/jspui/handle/tede/891.
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Previous issue date: 2009-12-08This work analyzes the relationship between communication and sustainability in community universities in the State of São Paulo which are part of the ABRUC (Brazilian Association of Community Universities). The objective is to examine the image of these universities, based on the communication strategies used in their institutional portals. It seeks to understand whether and how they use the fact that they are community universities as a means of differentiation in their institutional marketing. This research is qualitative, using Yin s (2005) methodology of multiple case study. Some aspects of Bardin s (2006) Content Analysis are also used, to categorize the terms that identify the community values. The portals of community universities located in the ABC region of São Paulo (Universidade Metodista do Estado de São Paulo UMESP, Centro Universitário Engenharia Industrial FEI and Centro Universitário Fundação Santo André FSA), constitute the main corpus of this research. The technique used to analyze the portals was structured based on the work of Vilella (2003). Aspects were evaluated relating to ease of navigation in the use of the information, namely: Usability, functionality and content. The data collection period was one month, distributed as follows: One week during the enrolment period for the university entrance exams, and three weeks at the start of the 2008 academic year. In the analysis of the construction of institutional image, it was also observed, based on the institutions economic and financial results, that there is a correlation between communication policy and financial sustainability. The main results were: a) there are no clearly visible community values in the institutional portals; b) the portals follow traditional patterns, without incorporating technological innovations that would guarantee visibility and transparency in the institutions actions; c) there is a correlation between the economic-financial results and the community differential as a communication strategy, and the sustainability of the institutions.(AU)
Este trabalho analisou a relação entre comunicação e sustentabilidade em universidades comunitárias no Estado de São Paulo associadas à ABRUC (Associação Brasileira das Universidades Comunitárias). O objetivo foi examinar a imagem das universidades, a partir das estratégias de comunicação utilizadas nos portais institucionais. Procurou entender se e como utilizam o diferencial de caráter comunitário no marketing institucional. A pesquisa é de natureza qualitativa, tendo como metodologia central o estudo de caso múltiplos de Yin (2005). Foram também utilizados alguns dos aspectos da Análise de Conteúdo de Bardin (2006) para a categorização dos termos que identificam os valores comunitários. Os portais das universidades comunitárias localizadas na região do ABC paulista (Universidade Metodista do Estado de São Paulo UMESP, Centro Universitário Engenharia Industrial FEI e Centro Universitário Fundação Santo André FSA), se constituem no corpus principal desta pesquisa. A técnica para a análise dos portais foi estruturada a partir do trabalho de Vilella (2003). Foram avaliados aspectos voltados para a facilidade da navegação no uso das informações, tais como: usabilidade, funcionalidade e conteúdo. O período para a coleta de dados foi de um mês, assim distribuído: uma semana durante o período de inscrições para o vestibular e três semanas no início do período letivo do ano de 2008. Como parte da análise da construção da imagem institucional foi também verificado, a partir dos resultados econômicos e financeiros, se existe correlação entre a política de comunicação das instituições comunitárias e a sustentabilidade financeira. Os principais resultados foram: a) não existe uma visibilidade clara dos valores comunitários nos portais institucionais; b) os portais seguem os padrões tradicionais, sem incorporar as inovações tecnológicas, que garantam visibilidade e transparência nas ações das instituições; c) existe correlação entre os resultados econômico-financeiros e o diferencial comunitário como estratégia de comunicação e sustentabilidade das instituições.(AU)
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Van, der Bijl Leendert. "Verification of patient position for proton therapy using portal X-Rays and digitally reconstructed radiographs." Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/1250.
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Thompson, Wendy M. "Correlating responses of portable field instruments used for testing aggregate and soil pavement layers /." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd2840.pdf.
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Ramos, Danusa de Souza. "Elastografia hepatoesplênica para predizer varizes esofágicas em pacientes com hipertensão portal não cirrótica: estudo de acurácia diagnóstica." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5168/tde-07112018-114450/.
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Introdução: elastografia ultrassônica é um método não invasivo validado e rotineiro para a determinação indireta do grau de fibrose hepática e em investigação para predizer a presença de varizes esofágicas. Entretanto, a elastografia foi validada somente em doenças que evoluem para cirrose. Na revisão de literatura que realizamos, observamos que há escassez de estudos de acurácia diagnóstica em pacientes com hipertensão portal não cirrótica. Objetivos: avaliar a acurácia diagnóstica das técnicas de elastografia hepatoesplênica (transitória por FibroScan e ARFI) para predizer a presença de varizes esofágicas e se as varizes são de risco de sangramento em pacientes com hipertensão portal não cirrótica. Avaliar a concordâncias das duas técnicas e correlacioná-las com outros índices (plaquetas/baço, APRI e FIB-4). Métodos: Foram incluídos pacientes com diagnóstico confirmado das seguintes condições: oclusão da veia porta extra-hepática, esquistossomose mansônica, hipertensão portal não cirrótica idiopática e fibrose hepática congênita. A endoscopia digestiva alta foi considerada como marcador da presença de hipertensão portal clinicamente significante. Critérios de inclusão: idade acima de um ano; diagnóstico etiológico definido; concordância do paciente ou responsável legal em participar do estudo. Critérios de exclusão: cirrose, confirmada pela combinação de critérios diagnósticos clínicos, de imagem e laboratoriais ou pela biópsia hepática quando o resultado estivesse disponível; hipertensão portal pós sinusoidal; condições que impeçam tecnicamente a realização da elastografia (ascite volumosa e insuficiência cardíaca); esplenectomia; gestação; carcinoma hepatocelular avançado. O desenho do estudo foi prospectivo, transversal, de acordo com a metodologia STARD, avaliando a acurácia, sensibilidade, especificidade, valores preditivos positivos e negativos e razões de verossimilhança positiva e negativa. Procedimentos no estudo: consulta aos dados de prontuário; ultrassonografia abdominal e elastografia hepatoesplênica com os equipamentos/métodos FibroScan e ARFI. Os pontos de corte foram determinados por curva ROC. Resultados: os valores de elastografia transitória hepática por FibroScan foram de 5,91 ± 1,87 kPa na oclusão da veia porta extra-hepática, 8,89 ± 3,96 kPa na esquistossomose, 10,60 ± 3,89 kPa na hipertensão portal não cirrótica idiopática e 10,30 ± 4,14 kPa na fibrose hepática congênita, enquanto os valores de ARFI foram de 1,27 ± 0,23 m/s; 1,35 ± 0,45 m/s; 1,43 ± 0,40 m/s; 1,55 ± 0,39 m/s; respectivamente. Os valores de elastografia transitória esplênica por FibroScan foram de 60,82 ± 20,56 kPa na oclusão da veia porta extra-hepática, 54,16 ± 22,94 kPa na esquistossomose, 52,64 kPa ± 21,97 kPa na hipertensão portal não cirrótica idiopática e 48,50 ± 24,86 kPa na fibrose hepática congênita, enquanto os valores de ARFI foram de 3,22 ± 0,62 m/s; 3,01 ± 0,74 m/s; 2,86 ± 0,53 m/s; 2,80 ± 0,55 m/s; respectivamente. A elastografia esplênica por FibroScan com ponto de corte 65,1 kPa apresentou acurácia de 0,62 (intervalo de confiança 95% 0,46-0,78; p=0,121) para presença de varizes. Para predizer varizes de alto risco de sangramento, o melhor ponto de corte foi 40,05 kPa, que apresentou acurácia de 0,63 (intervalo de confiança 95% 0,52-0,76; p=0,016). A elastografia esplênica ARFI com ponto de corte de 2,67m/s apresentou acurácia de 0,64 (intervalo de confiança 95%, 0,50-0,78; p=0,065) para presença de varizes. O melhor ponto de corte para predizer varizes de alto risco de sangramento com esse método foi de 3,17m/s, que apresentou acurácia de 0,61 (intervalo de confiança 95%, 0,51- 0,71; p=0,033). Conclusões: métodos de elastografia esplênica apresentaram uma acurácia moderada e valor preditivo positivo elevado para diagnosticar presença de varizes. A elastografia transitória esplênica por FibroScan quando associada à razão plaqueta/baço apresentou acurácia moderada com especificidade alta para predizer varizes de alto risco de sangramento. Entretanto, considerável superposição de valores foi observada entre pacientes com e sem varizes esofagianas, o que limita a aplicação a utilidade clínica do métodoBackground and rationale: transient elastography is a noninvasive, validated, method allowing evaluation of liver fibrosis by measurement of liver stiffness and under investigation to predict the presence of esophageal varices. However, elastography has been validated only in diseases that progress to cirrhosis. In a literature review we found few studies on diagnostic accuracy in patients with non-cirrhotic portal hypertension. Aims: to evaluate the accuracy of hepatosplenic elastography (FibroScan and ARFI) to predict the presence of esophageal varices and whether varices are at risk of bleeding in patients with non-cirrhotic portal hypertension. To evaluate the concordances of the two techniques and correlate them with other indexes such as the platelet /spleen diameter ratio, APRI and FIB-4. Methods: patients with confirmed diagnosis of the following conditions were included: extrahepatic portal vein occlusion, schistosomiasis, idiopathic non-cirrhotic portal hypertension and congenital hepatic fibrosis. Upper digestive endoscopy was considered as a marker of the presence of clinically significant portal hypertension. Inclusion criteria: age above one year; defined etiological diagnosis; agreement of the patient or legal guardian to participate in the study. Exclusion criteria: cirrhosis confirmed by combination of clinical, imaging and laboratory diagnostic criteria or by liver biopsy when the result was available; post sinusoidal portal hypertension; conditions that technically preclude the performance of elastography (massive ascites and heart failure); splenectomy; pregnancy; advanced hepatocellular carcinoma. The study design was prospective, transversal, according to the STARD methodology, evaluating the accuracy, sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios. The procedures of the study were: review of medical records data, abdominal ultrasonography and hepatosplenic elastography with FibroScan and ARFI equipment / methods. Cut-off points for elastography were determined by ROC curves. Results: liver stiffness measurement by FibroScan were 5.91 ± 1.87 kPa in extrahepatic portal vein occlusion, 8.89 ± 3.96 kPa in schistosomiasis, 10.60 ± 3.89 kPa in portal hypertension non-cirrhotic idiopathic and 10.30 ± 4.14 kPa in congenital hepatic fibrosis, whereas by ARFI were 1.27 ± 0.23 m/s; 1.35 ± 0.45 m/s; 1.43 ± 0.40 m/s; 1.55 ± 0.39 m/s; respectively. Spleen stiffness measurement by FibroScan were 60.82 ± 20.56 kPa in extrahepatic portal vein occlusion, 54.16 ± 22.94 kPa in schistosomiasis, 52.64 ± 21.97 kPa in idiopathic non-cirrhotic portal hypertension, and 48.50 ± 24.86 kPa in congenital hepatic fibrosis, while by ARFI were 3.22 ± 0.62 m/s; 3.01 ± 0.74 m/s; 2.86 ± 0.53 m/s; 2.80 ± 0.55 m/s; respectively. Liver stiffness measurement by FibroScan with a cut-off of 65.1 kPa had an accuracy of 0.62 (95%confidence interval, 0.46-0.78, p=0.121) for the presence of esophageal varices. The best cut-off point for predicting the presence of varices at high risk of bleeding was 40.05 kPa (accuracy, 0.63, 95% confidence interval, 0.52-0.76, p = 0.016). The spleen stiffness measurement by ARFI with a cut-off of 2.67 m/s showed (accuracy, 0.64, 95% confidence interval, 0.50-0.78, p=0.065) for the presence of esophageal varices. The best cut-off point for predicting the presence of varices at high risk of bleeding was 3.17 m/s (accuracy, 0.61, 95% confidence interval, 0.51-0.71, p=0.033) for varices at high risk of bleeding. Conclusions: spleen stiffness measurement by transient elastography (FibroScan and ARFI) presented a moderate accuracy and a high positive predictive value to diagnose the presence of esophageal varices. Spleen stifness by FibroScan when associated with platelet/spleen diameter ratio, there is a moderate accuracy with a high specificity to predict varices at high risk of bleeding. However, overlapping values between patients with or without varices was high and this precludes the clinical applicability of these methods
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Gomes, Micael Carmo Côrtes [UNESP]. "Portas entreabertas: em busca de uma educação sensível a partir das imagens, espaços e narrativas com teatro-educação." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/115855.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este estudo teve o objetivo analisar pistas de uma Educação Sensível por meio de uma Pedagogia do Teatro/Teatro-Educação a partir dos seus ‘saberes e saber-fazer Teatro em práticas educativas. O trabalho fundamenta-se na Sócio- Antropologia do Cotidiano, tendo por referência a Sociologia do Cotidiano, os estudos da razão sensível de Michel Maffesoli bem como na pedagogia do teatro. Com base nos procedimentos metodológicos, optou-se pela pesquisa Etnográfica na educação, delimitando o terreno ao qual o pesquisador permaneceu como observador-participante, isto é, no interior de um Galpão denominado como “Escola do Presídio” do Interior do Estado de São Paulo e os informantes dessa investigação, os “Monitores Culturais Detentos”. Entre os meses de maio de 2008 a novembro de 2009, foram realizadas observações, anotadas em diário de campo, a partir do contato com o grupo local (Centro de Trabalho e Educação e os Monitores Detentos) bem como um levantamento sobre o cotidiano desse Galpão escola (documentos da instituição, atividades culturais, aulas dos monitores, desenhos, maquetes da escola, fotos e filmagens) e, ao longo dessa investigação, atividades de cunho artístico-estético-pedagógica a partir da temática, Teatro-Educação, realizadas pelo pesquisador como, por exemplo: Grupo de Estudos; Laboratório do Brincar com Teatro; Pesquisa Cênica (Confecções de Máscaras para a representação de sua Dramaturgia Biográfica de Si) e as entrevistas semiestruturadas com os seis monitores envolvidos tanto no trabalho da escola (distribuídos entre as áreas de Alfabetização de Jovens e Adultos, os Ciclos I, II (I - 1ª a 4ª -, II - 5ª a 8ª - e o Ensino Médio) quanto nessa investigação. Assim, o diário de campo confeccionado permitiu a descrição do universo vivido entre o pesquisador e os seis informantes da pesquisa que estão inseridos. A geração de dados constituiu a partir dos registros ...
This study aimed to analyze the tracks of a Sensitive Education through a Pedagogy of the Theatre from a Knowledge and Know-Do Theatre Education in educational practices. The work is based on the Socio-Anthropology of Everyday Life as a reference to Everyday Sociology and Michel Maffesoli’s studies of the Sensitive Reason. Based on the methodological procedures, we chose for Ethnographic Research, limiting the field to which the researcher remained as an observer-participant, to a building called the “School of the Penitentiary,” located in the interior of Sao Paulo, and the informants of the research, called “Cultural Monitors,” were the inmates. Observations were done from May, 2008 to November, 2009, and reported in a field journal based in the contact with the local group (Center for Labor and Education and the monitors (in custody) ), as well as a survey on this school daily life (documents of the institution, cultural activities, tutoring sessions, drawings, models of school, pictures and movies), and throughout this research, pedagogical-artistic activities based on Pedagogy of the Theatre: Theatre-Education, conducted by the researcher, such as: study group; theatre lab; scenic research (production of masks for the representation of an autobiographical drama) and semi-structured interviews with 06 (six) monitors, involved both with school work (distributed among the areas of adult and youth literacy , cycles I (1st to 4th grades) and II (5th to 8th grades) and High School as in this investigation and with this research. Thus, the field journal allowed the description of the common universe shared with the researcher and the six informants included in the study. Data generation was consisted of audio-visual records (photo ethnographic, video ethnographic), systematic observation, ethno biographic and video interviews. Thus, this research focused on the images, the spaces and the narratives, as possible clues to reveal ...
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Gomes, Micael Carmo Côrtes. "Portas entreabertas : em busca de uma educação sensível a partir das imagens, espaços e narrativas com teatro-educação /." Araraquara, 2012. http://hdl.handle.net/11449/115855.
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Orientador: Sueli Aparecida Itman MonteiroCo-orientador: Olga Pombo Martins
Banca: Elizabete Carvalho de Melo
Banca: Henrique Silvestre
Banca: Luci Muzzeti
Banca: Paulo Rennes Marçal Ribeiro
Resumo: Este estudo teve o objetivo analisar pistas de uma Educação Sensível por meio de uma Pedagogia do Teatro/Teatro-Educação a partir dos seus 'saberes e saber-fazer Teatro em práticas educativas. O trabalho fundamenta-se na Sócio- Antropologia do Cotidiano, tendo por referência a Sociologia do Cotidiano, os estudos da razão sensível de Michel Maffesoli bem como na pedagogia do teatro. Com base nos procedimentos metodológicos, optou-se pela pesquisa Etnográfica na educação, delimitando o terreno ao qual o pesquisador permaneceu como observador-participante, isto é, no interior de um Galpão denominado como "Escola do Presídio" do Interior do Estado de São Paulo e os informantes dessa investigação, os "Monitores Culturais Detentos". Entre os meses de maio de 2008 a novembro de 2009, foram realizadas observações, anotadas em diário de campo, a partir do contato com o grupo local (Centro de Trabalho e Educação e os Monitores Detentos) bem como um levantamento sobre o cotidiano desse Galpão escola (documentos da instituição, atividades culturais, aulas dos monitores, desenhos, maquetes da escola, fotos e filmagens) e, ao longo dessa investigação, atividades de cunho artístico-estético-pedagógica a partir da temática, Teatro-Educação, realizadas pelo pesquisador como, por exemplo: Grupo de Estudos; Laboratório do Brincar com Teatro; Pesquisa Cênica (Confecções de Máscaras para a representação de sua Dramaturgia Biográfica de Si) e as entrevistas semiestruturadas com os seis monitores envolvidos tanto no trabalho da escola (distribuídos entre as áreas de Alfabetização de Jovens e Adultos, os Ciclos I, II (I - 1ª a 4ª -, II - 5ª a 8ª - e o Ensino Médio) quanto nessa investigação. Assim, o diário de campo confeccionado permitiu a descrição do universo vivido entre o pesquisador e os seis informantes da pesquisa que estão inseridos. A geração de dados constituiu a partir dos registros ...
Abstract: This study aimed to analyze the tracks of a Sensitive Education through a Pedagogy of the Theatre from a "Knowledge and Know-Do" Theatre Education in educational practices. The work is based on the Socio-Anthropology of Everyday Life as a reference to Everyday Sociology and Michel Maffesoli's studies of the Sensitive Reason. Based on the methodological procedures, we chose for Ethnographic Research, limiting the field to which the researcher remained as an observer-participant, to a building called the "School of the Penitentiary," located in the interior of Sao Paulo, and the informants of the research, called "Cultural Monitors," were the inmates. Observations were done from May, 2008 to November, 2009, and reported in a field journal based in the contact with the local group (Center for Labor and Education and the monitors (in custody) ), as well as a survey on this school daily life (documents of the institution, cultural activities, tutoring sessions, drawings, models of school, pictures and movies), and throughout this research, pedagogical-artistic activities based on Pedagogy of the Theatre: Theatre-Education, conducted by the researcher, such as: study group; theatre lab; scenic research (production of masks for the representation of an autobiographical drama) and semi-structured interviews with 06 (six) monitors, involved both with school work (distributed among the areas of adult and youth literacy , cycles I (1st to 4th grades) and II (5th to 8th grades) and High School as in this investigation and with this research. Thus, the field journal allowed the description of the common universe shared with the researcher and the six informants included in the study. Data generation was consisted of audio-visual records (photo ethnographic, video ethnographic), systematic observation, ethno biographic and video interviews. Thus, this research focused on the images, the spaces and the narratives, as possible clues to reveal ...
Doutor
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Penney, Graeme. "Registration of tomographic images to X-ray projections for use in image guided interventions." Thesis, King's College London (University of London), 2000. https://kclpure.kcl.ac.uk/portal/en/theses/registration-of-tomographic-images-to-xray-projections-for-use-in-image-guided-interventions(79e28525-ae06-4843-bd75-e1fab126e434).html.
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This thesis contributes to knowledge by describing a new method to allow information from a pre-operative 3D modality to be used during an intervention which is guided using 2D fluoroscopy images. An algorithm has been designed to obtain the pose of a CT volume with respect to a single fluoroscopy image. The registration algorithm is based on the production of digitally reconstructed radiographs from the CT volume, which are compared to the fluoroscopy image using a similarity measure. The novelty of the work described in this thesis is in both the design of the registration algorithm and also in investigating the specific requirements placed upon a similarity measure when attempting to register a pre-operative CT volume to an interventional fluoroscopy image. Seven similarity measures were investigated. Experiments were carried out to calculate the accuracy and robustness of the registration algorithm using each similarity measure. Initially fluoroscopy and CT images of a lumbar spine phantom were used. The accuracy of the registration algorithm was calculated by comparing the final registration positions with a ``gold-standard'' registration calculated using fiducial markers. More realistic datasets were simulated using the phantom fluoroscopy image with clinical image features overlaid. Results show that the introduction of soft-tissue structures and interventional instruments into the phantom image can have a large effect on the performance of some similarity measures previously applied to 2D-3D image registration. The similarity measures were also tested on clinical data from aortic stenting procedures, where k-fold cross validation was used to obtain an estimate of the registration accuracy. The results from these experiments showed that two measures were able to register accurately (RMS rotational error of 0.76 degrees and RMS in-plane translational error of 0.85mm) and robustly (10% failure rate) even when soft-tissue structures and interventional instruments were present as differences between the images. These two measures were pattern intensity and gradient difference. Finally the thesis describes a novel combination of the 2D-3D registration algorithm with a deformation algorithm. The registration algorithm was used to obtain information on the relative movement of the vertebrae between the pre-operative CT image and interventional fluoroscopy image. This information was then used to warp the pre-operative modality so that it more accurately represented the intra-operative scene.
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Billa, Anka Babu. "Development of an Ultra-Portable Non-Contact Wound Measurement System." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1495237287295576.
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