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1
Simpson, David Elliott. "Maximum entropy image processing in two and three dimensional single photon nuclear medicine imaging." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259973.
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Prasai, Persis. "Multimodality image registration." Birmingham, Ala. : University of Alabama at Birmingham, 2006. http://www.mhsl.uab.edu/dt/2007m/prasai.pdf.
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Hinshaw, Kevin P. "Seeing structure : using knowledge to reconstruct and illustrate anatomy /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6882.
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Baum, Karl G. "Multimodal breast imaging : registration, visualization, and image synthesis /." Online version of thesis, 2008. http://hdl.handle.net/1850/7063.
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Kang, Xin, and 康欣. "Feature-based 2D-3D registration and 3D reconstruction from a limited number of images via statistical inference for image-guidedinterventions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B48079625.
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Traditional open interventions have been progressively replaced with minimally invasive techniques.
Most notably, direct visual feedback is transitioned into indirect, image-based feedback,
leading to the wide use of image-guided interventions (IGIs). One essential process of all IGIs is to
align some 3D data with 2D images of patient through a procedure called 3D-2D registration during
interventions to provide better guidance and richer information. When the 3D data is unavailable, a
realistic 3D patient-speci_c model needs to be constructed from a few 2D images.
The dominating methods that use only image intensity have narrow convergence range and are
not robust to foreign objects presented in 2D images but not existed in 3D data. Feature-based
methods partly addressed these problems, but most of them heavily rely on a set of \best" paired
correspondences and requires clean image features. Moreover, the optimization procedures used in
both kinds of methods are not e_cient.
In this dissertation, two topics have been studied and novel algorithms proposed, namely, contour
extraction from X-ray images and feature-based rigid/deformable 3D-2D registration.
Inspired by biological and neuropsychological characteristics of primary visual cortex (V1), a
contour detector is proposed for simultaneously extracting edges and lines in images. The synergy
of V1 neurons is mimicked using phase congruency and tensor voting. Evaluations and comparisons
showed that the proposed method outperformed several commonly used methods and the results are
consistent with human perception. Moreover, the cumbersome \_ne-tuning" of parameter values is
not always necessary in the proposed method.
An extensible feature-based 3D-2D registration framework is proposed by rigorously formulating
the registration as a probability density estimation problem and solving it via a generalized expectation
maximization algorithm. It optimizes the transformation directly and treats correspondences
as nuisance parameters. This is signi_cantly di_erent from almost all feature-based method in the
literature that _rst single out a set of \best" correspondences and then estimate a transformation
associated with it. This property makes the proposed algorithm not rely on paired correspondences
and thus inherently robust to outliers. The framework can be adapted as a point-based method with
the major advantages of 1) independency on paired correspondences, 2) accurate registration using
a single image, and 3) robustness to the initialization and a large amount of outliers. Extended to
a contour-based method, it di_ers from other contour-based methods mainly in that 1) it does not
rely on correspondences and 2) it incorporates gradient information via a statistical model instead of
a weighting function. Tuning into model-based deformable registration and surface reconstruction,
our method solves the problem using the maximum penalized likelihood estimation. Unlike almost
all other methods that handle the registration and deformation separately and optimized them sequentially,
our method optimizes them simultaneously. The framework was evaluated in two example
clinical applications and a simulation study for point-based, contour-based and surface reconstruction,
respectively. Experiments showed its sub-degree and sub-millimeter registration accuracy and
superiority to the state-of-the-art methods.
It is expected that our algorithms, when thoroughly validated, can be used as valuable tools for
image-guided interventions.published_or_final_version
Orthopaedics and Traumatology
Doctoral
Doctor of Philosophy
6
Gibson, Christopher John. "Three dimensional display of tomographic images using shaded surfaces." Thesis, Durham University, 1988. http://etheses.dur.ac.uk/6436/.
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Several medical imaging techniques are capable of producing tomographic images, corresponding to cross-sections through the body. A stack of adjacent sections contains three dimensional information about the organs of interest, and this can be presented on a two dimensional screen using shaded surface techniques. In order to facilitate the routine use of such images, algorithms and techniques were developed on a conventional medical imaging computer system in a hospital environment. Several object representation schemes were compared, and two new schemes were devised. The 'solid binary object' technique facilitated exploration of the interior of an object, while the 'ordered surface list' technique enabled real time display of object surfaces. Several shading algorithms were compared, and a local polynomial fitting routine was devised. This was found to be superior to other methods using objective evaluation of the accuracy of surface normal estimations, and subjective evaluation of the corresponding image appearance. The techniques developed were applied to a variety of data obtained using xray computed tomography, nuclear magnetic resonance and emission computed tomography. For display of myocardial tomograms, a technique was devised for superposition of colour coded coronary arteries, showing their relationship to observed perfusion defects. For display of time varying images of the heart, a rapid display routine was developed to enable ventricular wall motion to be evaluated from any angle. Colour display techniques were also applied to this data to produce single images which incorporated kinetic as well as morphological information. The results obtained have confirmed that shaded surface images can be produced using computers currently available in hospital imaging departments. Interactive object modification and real time object display can be achieved without requiring special hardware.
7
Narayanan, Sreeram. "Rapid 3d seed reconstruction from incomplete data sets for image guided prostate brachytherapy /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5825.
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Fan, Li. "3D reconstruction and deformation analysis from medical image sequences with applications in left ventricle and lung /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9999280.
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Quartararo, John David. "Semi-automated segmentation of 3D medical ultrasound images." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-020509-161314/.
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Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: 3d ultrasound; ultrasound; image processing; image segmentation; 3d image segmentation; medical imaging Includes bibliographical references (p.142-148).
10
關福延 and Folk-year Kwan. "An intelligent approach to automatic medical model reconstruction fromserial planar CT images." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243216.
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Nain, Delphine. "Scale-based decomposable shape representations for medical image segmentation and shape analysis." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11192006-184858/.
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Thesis (Ph. D.)--Computing, Georgia Institute of Technology, 2007.Aaron Bobick, Committee Chair ; Allen Tannenbaum, Committee Co-Chair ; Greg Turk, Committee Member ; Steven Haker, Committee Member ; W. Eric. L. Grimson, Committee Member.
12
Köpsén, Kristian. "Improving visualisation of bronchi in three-dimensional rendering of CT data." Thesis, Linköping University, Department of Biomedical Engineering, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8375.
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The medical imaging system Sectra PACS from Sectra Imtec contains a 3D mode that can be used for visualising image stacks from e.g. computed tomography. Various structures of human anatomy can be visualised in the 3D mode, but visualisations of the bronchial tree of the lungs rarely become good enough to be useful. The goal of this work was to investigate ways of improving such visualisations.
Various approaches were studied, evaluated and tested. The fact that most effort was needed for small structures with sizes similar to the resolution of the images made things slightly more complicated. A method classifying neighbourhoods based on local structure emerged as most promising, and was used as foundation for a proposed algorithm. It creates a mask representing the presence of bronchi, allowing the hiding of uninteresting structures in its proximity. The algorithm was then implemented so that it could be tested together with the existing system.
The method was found to work well and was able to detect the smaller tubes of the bronchial tree and output the desired classification mask. Its usefulness was somewhat reduced by issues relating to speed, and the fact that many computed tomography image stacks lack the necessary resolution for visualising the finer details of the bronchial tree.
13
Law, Kwok-wai Albert, and 羅國偉. "3D reconstruction of coronary artery and brain tumor from 2D medical images." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31245572.
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D'Urso, Paul Steven. "Stereolithographic biomodelling in surgery /." [St. Lucia, Qld.], 1998. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17881.pdf.
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Quartararo, John David. "Semi-Automated Segmentation of 3D Medical Ultrasound Images." Digital WPI, 2009. https://digitalcommons.wpi.edu/etd-theses/155.
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A level set-based segmentation procedure has been implemented to identify target object boundaries from 3D medical ultrasound images. Several test images (simulated, scanned phantoms, clinical) were subjected to various preprocessing methods and segmented. Two metrics of segmentation accuracy were used to compare the segmentation results to ground truth models and determine which preprocessing methods resulted in the best segmentations. It was found that by using an anisotropic diffusion filtering method to reduce speckle type noise with a 3D active contour segmentation routine using the level set method resulted in semi-automated segmentation on par with medical doctors hand-outlining the same images.
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Villela, Carlos Henrique Silveira. "Proposta e aplicação de um novo protocolo 3D no diagnóstico da assimetria facial utilizando-se da tomografia computadorizada." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263526.
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Orientador: Cecília Amélia de Carvalho ZavagliaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: O diagnóstico das assimetrias faciais tem sido realizado por meio de exames físicos e complementares. As tomadas radiográficas convencionais ainda são os recursos mais difundidos como exames complementares para o diagnóstico das assimetrias faciais. Hoje, novas técnicas de obtenção de imagem podem fornecer visualizações tridimensionais do complexo craniofacial. Estas, por sua vez, podem eliminar magnificações e demagnificações quando da obtenção de mensurações. A imagem tridimensional, utilizando-se de soluções computacionais, pode ser movimentada em diversas direções. Este recurso favorece a cranioscopia, técnica pela quais grandes e médias assimetrias são reconhecidas em qualquer região do complexo craniofacial. A quantificação de assimetrias menores pode ser reconhecida por mensurações realizadas no biomodelo 3D virtual, ou seja, pela craniometria. Alguns protocolos 3D já foram propostos com a finalidade de qualificar e/ou quantificar a assimetria facial. Este trabalho propõe um novo protocolo 3D que faz uso das novas técnicas de aquisição e tratamento de imagens. Utiliza-se então da tomografia computadorizada e tendo como meta qualificar e quantificar a assimetria facial. Para isso, utiliza-se da marcação de pontos anatômicos verdadeiros, criando condições para que mensurações lineares e angulares sejam realizadas. Assim, assimetrias faciais poderão ser observadas, bem como as respostas individuais aos tratamentos propostos
Abstract: The diagnosis of facial asymmetry has been done using clinical and complementary examinations. The conventional radiographic images have still been the most spread resources as complementary examinations for facial asymmetry diagnosis. Nowadays, new image acquisition techniques can give three dimensional visualizations of the craniofacial complex. This way, it is possible to eliminate magnifications and demagnifications in measurements obtained using conventional radiographic techniques. The three dimensional image, using computational solutions, can be moved in different directions. This capability is favorable to cranioscopy, which is a technique used to recognize big and medium asymmetries in any part of the craniofacial complex. The qualification and quantification of small asymmetries can be done using measurements made in 3D virtual biomodel. Few 3D protocols have been proposed with the aim of qualify and quantify facial asymmetry. This work proposes a new 3D protocol which uses new image acquisition and treatment techniques based on computerized tomography, aimed to qualify and quantify facial asymmetry. To do that, it is used true anatomical landmarks marking process, which gives conditions to make linear, angular, area and volume measurements with positive recognitions and precision. Therefore, small facial asymmetries will be possible to be observer, as well as the individual responses to treatments, been them surgical, orthopedical or orthodontical
Mestrado
Materiais e Processos de Fabricação
Mestre em Engenharia Mecânica
17
Chan, Ho-Ming. "A supervised learning framework for multi-modal rigid registration with applications to angiographic images /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?COMP%202003%20CHAN.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 60-62). Also available in electronic version. Access restricted to campus users.
18
Wang, Xiaoting, and 王筱婷. "Topological analysis and visualization of micro structure of trabecular bone." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B31228380.
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Huang, Wei. "Automatic affine and elastic registration strategies for multi-dimensional medical images." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-050207-145713/.
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Yauri, Vidalón José Elías. "Ferramentas interativas de auxílio a diagnóstico por neuro-imagens 3D." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260025.
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Orientador: Wu Shin-TingDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: Por apresentar alta resolução espacial e espectral, é crescente o uso de imagens de ressonância magnética tanto no estudo dos órgãos humanos como também no diagnóstico das anormalidades estruturais e funcionais e no planejamento e treinamento cirúrgico. Junto com a rápida evolução dos algoritmos de processamento de imagens médicas, surgiram na última década aplicativos de diagnósticos assistidos por computador especializados em mamografia, angiografia e imagens da região torácica. A complexidade estrutural do cérebro e as diferenças anatômicas individuais do crânio constituem, no entanto, ainda desafios ao desenvolvimento de um sistema de diagnóstico especializado em neuro-imagens. A intervenção de especialistas é muitas vezes imprescindível na identificação e na interpretação dos achados radiológicos. Nesta dissertação, propomos o uso de três técnicas para auxiliar os especialistas da área médica na busca por achados radiológicos sutis de forma interativa. São apresentados dois objetos de interação, lente móvel e sonda volumétrica, que permitem atualizar continuamente os dados em foco enquanto são manipulados. Com isso, é possível investigar regiões cerebrais de interesse preservando o seu contexto. E, a fim de facilitar a percepção visual das variações funcionais ou estruturais sutis, propomos utilizar um editor de funções de transferência 1D para realçar ou aumentar o contraste entre os voxels adjacentes. As ferramentas foram avaliadas por um grupo de especialistas em neuro-imagens do Laboratório de Neuro-imagens da Faculdade de Ciências Médicas da Unicamp
Abstract: Because of its high spatial and spectral resolution, it is increasing the use of magnetic resonance images both in the study of human organs as well as in the diagnosis of structural and functional abnormalities and in the surgery planning and training. Along with the rapid evolution of medical image processing algorithms, computer-aided diagnostics systems specialized in mammography, angiography, and computed tomography and magnetic resonance of the thorax have emerged in the last decade. The structural complexity of the brain and individual anatomical shape of skulls are, however, challenges in developing a diagnostic system specializing in neuro-imaging. Expert interventions are still essential both in the identification and in the interpretation of radiological findings. In this dissertation, we propose the use of three techniques to aid the medical experts in the search of subtle findings in an interactive way. We present two widgets, movable lens and volumetric probe, that allow one to update continuously the volume data in focus while are manipulated. In this way, it is possible to investigate brain regions of interest preserving its context. And, in order to facilitate the visual perception of the subtle functional or structural changes, we propose to use an editor of 1D transfer function to enhance or to increase the contrast between adjacent voxels. The tools were assessed by the neuro-imaging experts of the Laboratory of Neuro-Images of the Faculty of Medical Sciences of Unicamp
Mestrado
Engenharia de Computação
Mestre em Engenharia Elétrica
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Jóia, Filho Paulo. "Reconstrução e geração de malhas em estruturas biomecânicas tridimensionais para análise por elemento finitos /." Bauru : [s.n.], 2008. http://hdl.handle.net/11449/90831.
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Orientador: Edson Antonio Capello SousaBanca: Sérgio Scheer
Banca: José Eduardo Cogo Castanho
Resumo: Uma das primeiras fases da análise estrutural por elementos finitos é a criação do modelo geométrico. Este modelo deve representar fielmente a estrutura no que diz respeito a ângulos, dimensões e forma. Quando os objetos de estudo são estruturas biomecânicas, a dificuldade na realização das análises aumenta, primeiro porque os modelos considerados apresentam geometria quase sempre irregular, segundo pela dificuldade na realização de experimentos desta natureza, já que envolvem, em geral, organismos e tecidos vivos. Inserida, portanto, no contexto de Modelagem Científica Computacional, esta pesquisa procurou aplicar a computação a outras áreas do conhecimento, com o objetivo de criar modelos computacionais para situações em que é inviável testar ou medir as diversas soluções possíveis para um fenômeno a partir de modelos experimentais, neste caso, regiões ósseas. Para atingir este objetivo um programa computacional foi desenvolvido: o bioMeshCreate. O bioMeshCreate é uma aplicação final, independente, multi-plataforma, orientado a objeto, implementado em C++ com o auxílio de um toolkit de visualização científica, o VTK (The Visualization Toolkit), e seu objetivo principal é reconstruir estruturas ósseas tridimensionais a partir de seções planas, normalmente imagens médicas digitais obtidas por exames de tomografia computadorizada ou ressonância magnética. A aplicação também permite visualizar as fatias planas, gerar a malha sobre a superfície reconstruída, aplicar filtros de redução de elementos e suavização de superfícies e integrar o volume obtido com softwares de análise por elementos finitos, a fim de completar a análise sobre a estrutura. Ainda é possível exportar dados em formatos compatíveis com processos de prototipagem rápida e gerar modelos de realidade virtual, os quais podem ser distribuídos e visualizados em um browser... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: One of the first phases of the structural analysis by finite elements is to create a geometric model. This model must faithfully represent the structure in what is related to angles, dimensions and form. When the study objects are biomechanical structures, the level of difficulty in the accomplishment of the analyses increases, first because the considered models present geometry almost always irregular, second for the difficulty for the accomplishment of experiments of this nature, as they involve, in general, organisms and live tissues. Inserted, therefore, in the context of Scientific Computational Modeling, this research tried to apply the computation to other areas of knowledge, with the objective of creating computational models for situations in which testing or measuring the several possible solutions for a phenomenon starting from experimental models isn't viable, in this case, bone areas. To reach this purpose, a computational program was developed: the bioMeshCreate. The bioMeshCreate is a final application, independent, multi-platform, object-oriented, developed in C++ with the support of a toolkit for scientific visualization, the VTK (The Visualization Toolkit), and its main objective is to rebuild three-dimensional bone structures starting from plane sections, usually digital medical images obtained by exams of computed tomography or magnetic resonance. The application allows the visualization plane slices, to generate the mesh on the rebuilt surface, to apply filters of elements reduction and mesh smoothing and to integrate the volume obtained with finite elements analysis softwares, in order to complete the analysis on the structure. It is still possible to export data in compatible formats with rapid prototyping processes, and to generate virtual reality models, which can be distributed and visualized in a browser. Tests with patients' real data were accomplished... (Complete abstract click elctronic access below)
Mestre
22
Wong, Victy Yee Wa. "Four-dimensional radiation therapy for thoracic carcinoma : dosimetric evaluation using deformable image registration." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/9215/.
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Respiratory motion remains a significant challenge for radiation therapy in targeting the tumour. The use of planning margins to avoid geometrical miss of the target volume during respiration results in excessive lung tissue irradiation that limits the prescribed dose to be safely delivered and escalated for better therapeutic gain. The purpose of this study was to develop effective dose planning techniques for treatment to be performed under natural patient breathing. The techniques accounted for the dosimetric influences of tumour movement and aimed to provide an optimized treatment volume by minimizing the internal target volume (ITV) without compromising the target coverage. In the study, the accumulated 4D dose distribution over the tumour volume was calculated using deformable image registration (DIR). A DICOM-RT based tool-box was specially developed for automated 4D dose calculation and evaluations. A new concept of defining the internal target volume from 4D dose coverage, namely inverse ITV (iITV) was introduced via the dose volume enclosed by the minimum accumulated dose in the tumour during the respiratory cycle. The dosimetric advantages of using this iITV with reference to the conventional ITV were confirmed in nine clinical cases by an average dose volume reduction of 16.4% (ranging from 2.3% to 29.9%). 4D radiotherapy involves complex dose distribution which was found to be affected by a number of factors including tumour size, magnitude of tumour displacement, tumour motion characteristics and the reference phases selected for dose planning. Our findings indicate that optimal dose planning was generally, but not always, achieved with the planning CT performed at the temporal mean tumour position and the degree of target coverage maximization strongly depends on the nature of tumour movement. Moreover, the conventionally geometric defined treatment margin could over estimate the treatment volume for a required target coverage. In conclusion, 4D dose calculation based on DIR offers realistic dose estimation, as both geometric and temporal factors are considered, and also provides optimal dose plans by minimizing the treatment volume. However, 4D radiation planning involves a number of factors resulting from the properties of tumours (eg. tumour size, amplitude and characteristics of tumour motion, etc) and from the procedure of treatment planning (eg. reference phase for dose planning, penumbra of dose beam, employed treatment volume etc) that interactively affect the resultant dosimetry. Since these factors vary patient-by-patient, there is no single formula or universal solution that can be used to obtain optimal dose planning. The 4D dose toolbox developed in this study could however provide a user friendly platform for 4D dose calculation and analysis, and allow the optimal treatment modalities and planning techniques to be determined for individuals.
23
Armit, Christine Marie. "Promoting physical activity in general practice : a randomised trial to test the efficacy of three strategies /." [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19377.pdf.
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Jóia, Filho Paulo [UNESP]. "Reconstrução e geração de malhas em estruturas biomecânicas tridimensionais para análise por elemento finitos." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/90831.
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Uma das primeiras fases da análise estrutural por elementos finitos é a criação do modelo geométrico. Este modelo deve representar fielmente a estrutura no que diz respeito a ângulos, dimensões e forma. Quando os objetos de estudo são estruturas biomecânicas, a dificuldade na realização das análises aumenta, primeiro porque os modelos considerados apresentam geometria quase sempre irregular, segundo pela dificuldade na realização de experimentos desta natureza, já que envolvem, em geral, organismos e tecidos vivos. Inserida, portanto, no contexto de Modelagem Científica Computacional, esta pesquisa procurou aplicar a computação a outras áreas do conhecimento, com o objetivo de criar modelos computacionais para situações em que é inviável testar ou medir as diversas soluções possíveis para um fenômeno a partir de modelos experimentais, neste caso, regiões ósseas. Para atingir este objetivo um programa computacional foi desenvolvido: o bioMeshCreate. O bioMeshCreate é uma aplicação final, independente, multi-plataforma, orientado a objeto, implementado em C++ com o auxílio de um toolkit de visualização científica, o VTK (The Visualization Toolkit), e seu objetivo principal é reconstruir estruturas ósseas tridimensionais a partir de seções planas, normalmente imagens médicas digitais obtidas por exames de tomografia computadorizada ou ressonância magnética. A aplicação também permite visualizar as fatias planas, gerar a malha sobre a superfície reconstruída, aplicar filtros de redução de elementos e suavização de superfícies e integrar o volume obtido com softwares de análise por elementos finitos, a fim de completar a análise sobre a estrutura. Ainda é possível exportar dados em formatos compatíveis com processos de prototipagem rápida e gerar modelos de realidade virtual, os quais podem ser distribuídos e visualizados em um browser...
One of the first phases of the structural analysis by finite elements is to create a geometric model. This model must faithfully represent the structure in what is related to angles, dimensions and form. When the study objects are biomechanical structures, the level of difficulty in the accomplishment of the analyses increases, first because the considered models present geometry almost always irregular, second for the difficulty for the accomplishment of experiments of this nature, as they involve, in general, organisms and live tissues. Inserted, therefore, in the context of Scientific Computational Modeling, this research tried to apply the computation to other areas of knowledge, with the objective of creating computational models for situations in which testing or measuring the several possible solutions for a phenomenon starting from experimental models isn’t viable, in this case, bone areas. To reach this purpose, a computational program was developed: the bioMeshCreate. The bioMeshCreate is a final application, independent, multi-platform, object-oriented, developed in C++ with the support of a toolkit for scientific visualization, the VTK (The Visualization Toolkit), and its main objective is to rebuild three-dimensional bone structures starting from plane sections, usually digital medical images obtained by exams of computed tomography or magnetic resonance. The application allows the visualization plane slices, to generate the mesh on the rebuilt surface, to apply filters of elements reduction and mesh smoothing and to integrate the volume obtained with finite elements analysis softwares, in order to complete the analysis on the structure. It is still possible to export data in compatible formats with rapid prototyping processes, and to generate virtual reality models, which can be distributed and visualized in a browser. Tests with patients' real data were accomplished... (Complete abstract click elctronic access below)
25
Krefer, Andriy Guilherme. "Fusão de modelos 3D com imagens térmicas para aplicações médicas." Universidade Tecnológica Federal do Paraná, 2015. http://repositorio.utfpr.edu.br/jspui/handle/1/1407.
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CNPq; CAPESA termografia permite a visualização de valores de temperatura de um corpo por meio de imagens. Na área médica, encontra aplicações em oncologia, análise de queimaduras, doenças vasculares, doenças respiratórias, doenças de pele e como forma geral de verificação da vitalidade dos tecidos. A termografia 3D consiste de uma malha 3D com uma textura térmica projetada em sua superfície, oferecendo uma visualização mais precisa dos padrões de temperatura das estruturas anatômicas. Propõe-se, por meio do presente trabalho, um sistema capaz de combinar imagens termográficas 2D com sua malha 3D correspondente e, como resultado, entregar uma imagem termográfica 3D para aplicações médicas. Para isso foram utilizadas as técnicas de Otimização por Enxame de Partículas (PSO) e de reconstrução 3D Structure from Motion (SfM). Diferentemente de outros trabalhos na literatura, a malha 3D e as imagens térmicas não precisam ser adquiridas simultaneamente, não sendo necessário um arranjo mecânico dedicado. A malha 3D pode ter origem em um scanner 3D ou em uma imagem de ressonância magnética, por exemplo. Para avaliar os resultados, um phantom, isto é, um objeto estático de avaliação, com propriedades conhecidas, foi construído. Para tal, uma técnica inédita, utilizando placas de circuito impresso foi desenvolvida. Como resultado, comparações entre a saída do método proposto e o phantom, apresentaram um erro máximo de 3,73 mm e médio de 1,41 mm, com desvio padrão de 0,74 mm, em um phantom de 100 x 150 x 103,2 mm.
Thermography is an imaging method that allows temperature visualization of various regions of an object. In medicine, it finds applications related to oncology, burn trauma, vascular, respiratory and skin diseases, and as a general tissue vitality checking tool. 3D thermography adds tridimensional information to the conventional 2D thermography. It is made from a 3D mesh wrapped by thermal texture, enabling a more precise visualization of thermal patterns of anatomical structures. We propose a system capable of combining 2D thermal images with their corresponding 3D mesh, delivering a 3D thermogram for medical applications as a result. We used Particle Swarm Optimization (PSO) for mesh alignment and Structure from Motion (SfM) for 3D reconstruction in the present method. In contrast to most research found in the literature, the 3D mesh and the thermal images do not need to be acquired simultaneously, and a mechanical support for the thermal camera and the 3D scanner is not required. The 3D mesh may be acquired, for instance, from a 3D scanner or a magnetic resonance imaging machine. In order to evaluate the results, a phantom, that is, a static assessment object of known properties has been built. For this purpose, a novel technique using printed circuit boards has been developed. As a result, comparison between the output of the method and the phantom shows a maximum error of 3.73 mm and a mean error of 1.41 mm with 0.74 mm of standard deviation in phantom of 100 x 150 x 103.2 mm.
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Owodunni, Olalekan. "Three-dimensional particle image velocimetry." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612899.
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Ferreira, Alana Elisabeth Kuntze. "Análise cinemática da marcha de amputados transtibiais: comparação dos encaixes KBM e a vácuo." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/980.
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Introdução: A amputação transtibial é uma das amputações de membros inferiores mais frequentemente realizada. Objetivo: Este trabalho teve por objetivo comparar, através da análise tridimensional da marcha, as alterações de marcha de pacientes com amputação transtibial, previamente treinados, que utilizavam próteses com encaixe Kondylen Bettung Münster (KBM) e a vácuo. Metodologia: Foram avaliados voluntários com amputação transtibial que utilizavam encaixe KBM ou a vácuo disponibilizados pelos Sistema Único de Saúde (SUS). A amostra final foi de 12 participantes no grupo “KBM” e 5 no grupo “vácuo”. Todos eles passaram por um exame físico, que constou de goniometria, teste de força muscular e coleta de dados antropométricos. Eles também realizaram análise tridimensional (3D) da marcha. Para tal, eles foram paramentados com marcadores reflexivos em pontos anatômicos e os correspondentes da prótese, de acordo com o modelo Helen Hayes e caminharam por uma pista de 10 metros com uma velocidade auto selecionada. O sistema de captura consistiu em 6 câmeras Hawk e software Cortex versão 1.1.4.368, de captura e edição das caminhadas, ambos da Motion Analysis Corporation. A comparação entre os dois grupos foi realizada através da Pontuação do Perfil da Marcha (GPS), das Pontuações das Variáveis da Marcha (GVS) e dos parâmetros de tempo e espaço da marcha. Além disso, foi testada a correlação entre a GPS e as GVS e entre a GPS e os parâmetros de tempo e espaço da marcha. Resultados: Os dois grupos obtiveram velocidade da marcha significativamente menores, período de apoio significativamente maior e o tempo de apoio simples menor que o normal. Nos dois grupos ainda, os valores de GPS e GVS foram maiores que o normal, porém o “KBM” apresentou maiores desvios que o “vácuo”. Os maiores desvios do grupo do encaixe KBM foram nas GVS flexão/extensão dos quadris, flexão/extensão dos joelhos e dorsi/plantiflexão do tornozelo MIP, podendo assim caracterizar este como o padrão de desvio do Perfil de Análise do Movimento (MAP) deste grupo. O grupo “vácuo” teve os principais desvios nas GVS dorsi/plantiflexão dos tornozelos, flexão/extensão do joelho MIP e rotação pélvica, sendo este o padrão de desvio do MAP deste grupo. Encontraram-se, portanto, padrões diferentes de desvio nos dois grupos. Os dois grupos apresentaram desvios no MICL, os quais representam as compensações realizadas neste membro para possibilitar uma marcha mais funcional com a prótese. Os participantes que utilizaram o encaixe a vácuo apresentaram marcha mais simétrica que os participantes que utilizavam encaixe KBM. O grupo que utilizava o encaixe a vácuo obteve menores valores de GPS e de algumas GVS que o grupo “KBM”, entre elas estão a flexão/extensão do quadril MIP e MICL, flexão/extensão do joelho MIP e a flexão/extensão do joelho MICL, que foi a única diferença estatisticamente significante entre os grupos de encaixe. O mesmo grupo teve velocidade da macha maior que o grupo “KBM” e, apesar desta diferença não ter sido significativa, sugere uma maior funcionalidade da marcha com o encaixe a vácuo. Conclusão: Pode-se concluir que os indivíduos que utilizaram encaixe a vácuo apresentaram um padrão de marcha mais funcional e com menores desvios que aqueles que utilizaram encaixe KBM, quando comparados através da GPS, das GVS e dos parâmetros de tempo e espaço.Introduction: Transtibial amputation is one of the lower limb amputations more often performed. Objective: The aim of this study was to compare, using 3D gait analysis, gait deviations of patients with transtibial amputation, previously trained, using KBM and vacum prosthetic fittings. Methodology: Transtibial amputees that used Kondylen Bettung Münster (KBM) and vacuum prosthetic fitting waived by the Sistema Único de Saúde (SUS) were evaluated. The final sample consisted of 12 participants in the "KBM" group and 5 in the "vacuum" group. They all underwent a physical examination, which consisted of goniometry, muscle strength testing and anthropometric data. They also performed three-dimensional (3D) gait analysis. For this, they were vested with reflexive markers on anatomical and prosthetic corresponding landmarkers according to the Helen Hayes and walked across a 10-m walk-way at their self-selected speed. The capture system consisted of 6 cameras Hawk and the Cortex software version 1.1.4.368 for capturing and editing the trials, both from Motion Analysis Corporation. The Gait Profile Scores (GPS), Gait Variable Score (GVS) and temporal-spatial parameters performed the comparison between the two groups. In addition, we tested the correlation between GPS and GVS and between GPS and temporal-spatial parameters. Results: The two groups had significantly lower gait speed, significantly longer period of support and shorter time of single support than normal. In both groups, GPS and GVS values were higher than normal, but the "KBM" showed greater deviations than the "vacuum". The largest deviations from the KBM group was in the GVS hips flexion / extension, knees flexion / extension and ankle dorsi / plantarflexion MIP and can thus characterize this as the deviation pattern of the Movement Analysis Profile (MAP) for this group. The "vacuum" group had major deviations of the GVS ankles dorsi / platarflexion, knee flexion / extension MIP and pelvic rotation, the deviation pattern of MAP in this group. There were, therefore, different deviation patterns I the two groups. Both groups showed deviations in MICL, which represent the compensation made by this limb to enable a more functional gait with prosthesis. Participants who used vacuum prosthetic fitting showed more a symmetrical gait than participants that used KBM prosthetic fitting. The group that used vacuum prosthetic fitting had lower values of GPS and some GVS than "KBM" group; these include hips flexion / extension, MIP knee flexion / extension and MICL knee flexion / extension, which was the only statistically significant difference between the groups. The same group had greater walking speed than the "KBM" group and, although this difference was not significant, it suggests more functionality of gait with vacuum prosthetic fitting. Conclusion: It can be concluded that individuals who used the vacuum prosthetic fitting showed more functional gait pattern and smaller deviations than those that used KBM prosthetic fitting, compared by GPS, GVS and temporal-spatial parameters.
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Javid, Shawn Farhang. "Three-dimensional image processing using voxels." Thesis, University College London (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312149.
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Ettinger, Gil J. "Hierarchical three-dimensional medical image registration." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/10448.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 168-172).
by Gil J. Ettinger.
Ph.D.
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Walimbe, Vivek S. "Interactive, quantitative 3D stress echocardiography and myocardial perfusion spect for improved diagnosis of coronary artery disease." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1154710169.
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Adams, Charles N. "Three dimensional image synthesis : theory and application /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FAdams.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2003.Thesis advisor(s): Phillip E. Pace, Don Brutzman. Includes bibliographical references (p. 129-130). Also available online.
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Kapur, Tina. "Model based three dimensional medical image segmentation." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80007.
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Duranza, Sonia. "Three-dimensional image analysis using confocal microscopy." FIU Digital Commons, 1998. http://digitalcommons.fiu.edu/etd/3106.
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This thesis introduces imaging algorithms for three-dimensional data analysis and classification using confocal microscopy. The third dimension, depth information, is provided through the optical sectioning property of the confocal microscope. The theme of this thesis is to develop imaging techniques that extend beyond the traditional two-dimensional (2-D) spatial coordinate system into an augmented three-dimensional (3-D) world where analysis, interpretation, and the eventual classification of data is greatly enhanced. In the development of the proposed 3-D algorithms, three main objectives were sought: (1) establish proper 3-D mathematical extensions and practical implementations of 2-D standard formulations; (2) ensure that the process of classification overcomes the burden imposed by dependence in size and orientation through applications of the principal component transform and the log-spherical plot; and (3) address such issues as memory management and accelerated processing to reach the final objective of data recognition and classification effectively.
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Kinahan, Paul Eugene. "Analytic three dimensional image reconstruction from projections." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28492.
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This work presents an analytic three dimensional image reconstruction algorithm that was developed for a proposed volume-imaging PET scanner. The development of the algorithm was motivated by the scanner's ability to collect an order of magnitude more data than current PET systems and the lack of an efficient algorithm that could use the extra data.
The algorithm is based on an extension of the Recovery Operator of Orlov[68] and operates by convolution in object space. This method of operation sets it apart from other analytic direct image reconstruction algorithms that rely on Fourier transforms.
The algorithm is tested with ideal data and parameters that are appropriate to the new PET scanner. The results of the test show that the algorithm behaves as expected except for a 17% overshoot in the reconstructed value in one area. An explanation of this artifact is suggested, although not verified.
Finally, the efficacy of the algorithm is demonstrated by proving that it is functionally
equivalent to Fourier transform methods.Science, Faculty of
Physics and Astronomy, Department of
Graduate
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Hoyle, Rebecca Bryony. "Instabilities of three-dimensional patterns." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318044.
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Mlsna, Phillip Anthony 1956. "Color image enhancement by three-dimensional histogram modification." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278247.
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Histogram-based color image enhancement is usually accomplished by transforming from RGB coordinates to another coordinate system, modifying the components represented in that system, and converting the results back to RGB. Although a few methods function directly in RGB space, they also attempt to reduce dimensonality from the histogram's original three dimensions. Such methods seldom yield images that use the full extent of RGB color range. A new method called "histogram explosion" has been developed to perform true multivariate enhancement directly in RGB color space. Discussed are the algorithm's operational parameters, behavior, implementation, and possible improvements. Results show histogram explosion to be very effective and flexible in enhancing color images. Finally, two iterative methods are suggested as possible approaches for the extension of the histogram equalization algorithm to operate upon three dimensional histograms.
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Holzbach, Mark. "Three-dimensional image processing for synthetic holographic stereograms." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14767.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1987.Bibliography: leaves 54-55.
A digital image processing technique is presented that allows conventionally produced images to be prepared for undistorted printing in one-step holographic stereograms. This technique effectively predistorts the source 2D image set for a holographic stereogram to compensate for the distorting effects of its display geometry. The resulting stereograms can have undistort ed images that occupy space in front, back, and through the hologram surface. This technique is much more convenient that the current alternatives which either require unusual large optics, or much more intensive use of computer resources. It should therefore facilitate the fast and convenient production of one-step stereograms which are excellent 3D hardcopy displays with potential for applications that require fast visual communication of complex 3D information.
by Mark Holzbach.
M.S.
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Fini, John Michael. "Three dimensional image reconstruction from Fourier magnitude measurements." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43318.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 81-82).
by John Michael Fini.
M.Eng.
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McManigle, John E. "Three-dimensional geometric image analysis for interventional electrophysiology." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:2f36fa8e-9c64-4807-97c0-25e63398da7e.
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Improving imaging hardware, computational power, and algorithmic design are driving advances in interventional medical imaging. We lay the groundwork here for more effective use of machine learning and image registration in clinical electrophysiology. To achieve identification of atrial fibrosis using image data, we registered the electroanatomic map (EAM) data of atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) with MR (n = 16) or CT (n = 18) images. The relationship between image features and bipolar voltage was evaluated using single-parameter regression and random forest models. Random forest performed significantly better than regression, identifying fibrosis with area under the receiver operating characteristic curve (AUC) 0.746 (MR) and 0.977 (CT). This is the first evaluation of voltage prediction using image data. Next, we compared the character of native atrial fibrosis with ablation scar in MR images. Fourteen AF patients undergoing repeat PVI were recruited. EAM data from their first PVI was registered to the MR images acquired before the first PVI (‘pre-operative’) and before the second PVI ('post-operative' with respect to the first PVI). Non-ablation map points had similar characteristics in the two images, while ablation points exhibited higher intensity and more heterogeneity in post-operative images. Ablation scar is more strongly enhancing and more heterogeneous than native fibrosis. Finally, we addressed myocardial measurement in 3-D echocardiograms. The circular Hough transform was modified with a feature asymmetry filter, epicardial edges, and a search constraint. Manual and Hough measurements were compared in 5641 slices from 3-D images. The enhanced Hough algorithm was more accurate than the unmodified version (Dice coefficient 0.77 vs. 0.58). This method promises utility in segmentation-assisted cross-modality registration. By improving the information that can be extracted from medical images and the ease with which that information can be accessed, this progress will contribute to the advancing integration of imaging in electrophysiology.
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Kim, Taegeun. "Optical Three-Dimensional Image Matching Using Holographic Information." Diss., Virginia Tech, 2000. http://hdl.handle.net/10919/28362.
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We present a three-dimensional (3-D) optical image matching technique and location extraction techniques of matched 3-D objects for optical pattern recognition. We first describe the 3-D matching technique based on two-pupil optical heterodyne scanning. A hologram of the 3-D reference object is first created and then represented as one pupil function with the other pupil function being a delta function. The superposition of each beam modulated by the two pupils generates a scanning beam pattern. This beam pattern scans the 3-D target object to be recognized. The output of the scanning system gives out the 2-D correlation of the hologram of the reference object and that of the target object. When the 3-D image of the target object is matched with that of the reference object, the output of the system generates a strong correlation peak. This theory of 3-D holographic matching is analyzed in terms of two-pupil optical scanning. Computer simulation and optical experiment results are presented to reinforce the developed theory.
The second part of the research concerns the extraction of the location of a 3-D image matched object. The proposed system basically performs a correlation of the hologram of a 3-D reference object and that of a 3-D target object, and hence 3-D matching is possible. However, the system does not give out the depth location of matched 3-D target objects directly because the correlation of holograms is a 2-D correlation and hence not 3-D shift invariant. We propose two methods to extract the location of matched 3-D objects directly from the correlation output of the system. One method is to use the optical system that focuses the output correlation pattern along depth and arrives at the 3-D location at the focused location. However, this technique has a drawback in that only the location of 3-D targets that are farther away from the 3-D reference object can be extracted. Thus, in this research, we propose another method in which the extraction of a location for a matched 3-D object is possible without the aforementioned drawback. This method applies the Wigner distribution to the power fringe-adjusted filtered correlation output to extract the 3-D location of a matched object. We analyze the proposed method and present computer simulation and optical experiment results.Ph. D.
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Pacheco, Edward Flórez. "Quantificação da dinâmica de estruturas em imagens de medicina nuclear na modalidade PET." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3142/tde-08052012-114807/.
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A presença que tem hoje a Medicina Nuclear como modalidade de obtenção de imagens médicas é muito importante e um dos principais procedimentos utilizados hoje nos centros de saúde, tendo como grande vantagem a capacidade de conseguir analisar o comportamento metabólico do paciente, fazendo possíveis diagnósticos precoces. Este projeto está baseado em imagens médicas obtidas através da modalidade PET (Positron Emission Tomography) a qual está tendo uma crescente difusão e aceitação. Para isso, temos desenvolvido uma estrutura integral de processamento de imagens tridimensionais PET, a qual está constituída por etapas consecutivas que se iniciam na obtenção das imagens padrões (gold standard), sendo utilizados volumes simulados ou phantoms do Ventrículo Esquerdo do Coração criadas como parte do projeto, assim como geradas a partir do software NCAT-4D. A seguir, nos volumes simulados, é introduzido ruído quântico tipo Poisson que é o ruído característico das imagens PET e feita uma análise que busca certificar que o ruído utilizado corresponde efetivamente ao ruído Poisson. Em sequência é executada a parte de pré-processamento, utilizando para este fim, um conjunto de filtros tais como o filtro da mediana, o filtro da Gaussiana ponderada e o filtro que mistura os conceitos da Transformada de Anscombe e o filtro pontual de Wiener. Posteriormente é aplicada a etapa de segmentação que é considerada a parte central da sequência de processamento. O processo de segmentação é baseado na teoria de Conectividade Fuzzy e para isso temos implementado quatro diferentes abordagens: Algoritmo Genérico, Algoritmo LIFO, Algoritmo kTetaFOEMS e o Algoritmo utilizando Pesos Dinâmicos. Sendo que os três primeiros algoritmos utilizam pesos específicos selecionados pelo usuário, foi preciso efetuar uma análise para determinar os melhores pesos de segmentação que se reflitam numa segmentação mais eficiente. Finalmente, para terminar a estrutura de processamento, um procedimento de avaliação foi utilizado como métrica para obter quantitativamente três parâmetros (Verdadeiro Positivo, Falso Positivo e Máxima Distância) que permitiram conhecer o nível de eficiência e precisão de nosso processo e do projeto em geral. Constatamos que os algoritmos implementados (filtros e algoritmos de segmentação) são bastante robustos e atingem ótimos resultados chegando-se a obter, para o caso do volume do Ventrículo Esquerdo simulado, taxas de VP e FP na ordem de 98.49 ± 0.27% e 2,19 ± 0.19%, respectivamente. Com o conjunto de procedimentos e escolhas feitas ao longo da estrutura de processamento, encerramos o projeto com a análise de um grupo de volumes produto de um exame PET real, obtendo a quantificação destes volumes.The usefulness of Nuclear medicine nowadays as a modality to obtain medical images is very important, and it has turned into one of the main procedures utilized in Health Care Centers. Its great advantage is to analyze the metabolic behavior of the patient, by allowing early diagnosis. This project is based on medical images obtained by the PET modality (Positron Emission Tomography), which has won wide acceptance. Thus, we have developed an integral framework for processing Nuclear Medicine three-dimensional images of the PET modality, which is composed of consecutive steps that start with the generation of standard images (gold standard) by using simulated images or phantoms of the Left Ventricular Heart that were generated in this project, such as the ones obtained from the NCAT-4D software. Then Poisson quantum noise is introduced into the whole volume to simulate the characteristic noises in PET images and an analysis is performed in order to certify that the utilized noise is the Poisson noise effectively. Subsequently, the pre-processing is executed by using specific filters, such as the median filter, the weighted Gaussian filter, and the filter that joins the concepts of Anscombe Transformation and the Wiener filter. Then the segmentation, which is considered the most important and central part of the whole process, is implemented. The segmentation process is based on the Fuzzy Connectedness theory and for that purpose four different approaches were implemented: Generic algorithm, LIFO algorithm, kTetaFOEMS algorithm, and Dynamic Weight algorithm. Since the first three algorithms used specific weights that were selected by the user, an extra analysis was performed to determine the best segmentation constants that would reflect an accurate segmentation. Finally, at the end of the processing structure, an assessment procedure was used as a measurement tool to quantify some parameters that determined the level of efficiency and precision of our process and project. We have verified that the implemented algorithms (filters and segmentation algorithms) are fairly robust and achieve optimal results, assist to obtain, in the case of the Left Ventricular simulated, TP and FP rates in the order of 98.49 ± 0.27% and 2.19 ± 0.19%, respectively. With the set of procedures and choices made along of the processing structure, the project was concluded with the analysis of a volumes group from a real PET exam, obtaining the quantification of the volumes.
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Wan, Sau Kuen. "Modeling with panoramic image network for image-based walkthroughs /." access full-text access abstract and table of contents, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?mphil-cs-b1988588xa.pdf.
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Thesis (M.Phil.)--City University of Hong Kong, 2005."Submitted to Department of Computer Science in partial fulfillment of the requirements for the degree of Master of Philosophy" Includes bibliographical references (leaves 81-84)
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Sitter, David Norbert. "Space invariant modeling in three-dimensional optical image formation." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/13450.
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Lee, Choon. "Interframe image coding with three-dimensional gradient motion estimation." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08252008-162144/.
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Raouf, Abdul. "Three dimensional image structure in in-line Fraunhofer holography." Thesis, Brunel University, 1991. http://bura.brunel.ac.uk/handle/2438/7278.
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In this thesis a new theoretical model for the three dimensional images from a finite aperture in-line Fraunhofer hologram is presented. Existing work only deals with the case of single object, in this thesis this work has been extended to the case of two identical coplanar discs. The resulting image equation is solved numerically for several different limiting apertures and their results are compared with the image intensity data from the holograms recorded on Agfa BE 75HD film. Excellent quantitative agreement is found, verifying the theoretical predictions. Three different criteria for determining the disc diameter and disc separation describing their errors are discussed for both numerical and experimental data. A data acquisition system based upon a digital interfaced with a PC, and high resolution video camera is described.
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Roble, Douglas Raymond. "Computer assisted three dimensional rotoscoping for realistic image composition." Connect to resource, 1992. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1194555873.
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Stazyk, Michael Walter. "Radon Transform in three dimensional image reconstruction from projections." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28726.
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This thesis presents an algorithm for image reconstruction from projections intended for use in a new class of volume imaging PET scanners.
The algorithm is based on the inversion of the three dimensional Radon Transform as it applies to the truncated cylindrical detector geometry and is derived from the X-ray Transform inversion given by the Orlov recovery operator.
The algorithm is tested using Monte Carlo simulations of several phantom geometries
and employs a single iterative step to include all detected events in the reconstruction.
The reconstructed images are good representations of the original objects, however the iterative step is a source of some significant artefacts in the images.
Also discussed is the extension of the Radon Transform technique to a non-iterative method for three dimensional image reconstruction using all detected events.Science, Faculty of
Physics and Astronomy, Department of
Graduate
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Bennett, Stuart Charles. "Three-dimensional reconstruction outside of the laboratory." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708326.
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Gomersall, William Henry. "Deconvolution of three-dimensional medical ultrasound." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609431.
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Pagoulatos, Nikolaos. "Algorithms and systems for registration of two-dimensional and three-dimensional ultrasound images /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/6035.
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