Projections Reconstruction
Mostrando 1-12 de 22 artigos, teses e dissertações.
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1. 3D computer tomography for measurement of femoral position in acl reconstruction
Objective: To validate intra- and inter-class correlation coefficients of a transparent 3D-TC protocol and investigate relationships between different axial rotations.Methods: Twenty unilateral knee TCs (iSite - Philips) were evaluated by means of a transparent 3D-TC OsiriX Imaging Software (v.3.9.4), 3D MPR protocol. Mathematical model of femoral tunnel pro
Acta ortop. bras.. Publicado em: 2015-02
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2. Novas propostas em filtragem de projeções tomográficas sob ruído Poisson
In this dissertation we present techniques for filtering of tomographic projections with Poisson noise. For the filtering of the tomogram projections we use variations of three filtering techniques: Bayesian estimation, Wiener filtering and thresholding in Wavelet domain. We used ten MAP estimators, each estimator with a diferent probability density as prior
Publicado em: 2010
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3. Reconstrução tridimensional de objetos a partir das projeções de suas secções / Tridimensional objects reconstruction from the projections of theirs sections
Este trabalho trata da reconstrução tomográfica bidimensional e tridimensional, a partir de projeções, visando sua utilização em qualquer aplicação que necessite do volume completo do objeto em questão ou que necessite das imagens adquiridas dos- objetos projetados. Propicie-se utilizar um dos métodos pelo qual a tomografia Computadorizada gera as
Publicado em: 2010
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4. Métodos híbridos para reconstrução tomográfica de imagens usando POCS e teoria da estimação / Hybrid methods for tomographic image reconstruction using POCs and estimation theory
Nesta tese é apresentado um novo método de reconstrução de imagens, por tomografia de transmissão, de projeções sujeitas a ruído na contagem de fótons. O método de reconstrução selecionado utiliza a técnica POCS (Projections Onto Convex Sets). A estimação das projeções originais a partir das observações ruidosas se dá por meio de quatro m
Publicado em: 2007
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5. Aplicação de métodos tomográficos na reconstrução bi-dimensional de propriedades de chamas / Application of the tomographyc methods on bidimensional reconstruction of the flame properties
Fundamentally, flame diagnosis by tomographic imaging deals with reconstructing an image from its projections. In the strict sense of the word, a projection at a given angle is the integral of the image in the direction specified by that angle. However, in a loose sense, projection means the information derived from the emitted energies, at some angle, when
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/02/2006
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6. Development and applications of three-dimensional gamma ray tomography system using ray casting volume rendering techniques
Computed Tomography (CT) has made possible visualization of physical structures in the interior of an object in their real relative spatial position and orientation. Another important contribution of CT is to greatly improve abilities to distinguish regions with different gamma ray transmittance and to separate over-lying structures. The mathematical problem
Brazilian Journal of Physics. Publicado em: 2005-09
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7. Restauração das imagens do satélite CBERS-1 utilizando POCS.
A quantidade de aplicações oriundas do sensoriamento remoto tem aumentado significativamente nos últimos anos. Isso se deve, principalmente, à alta qualidade dos equipamentos a bordo dos sistemas sensores. Entre essa nova geração de satélites, o CBERS-1 (China-Brazil Earth Resources Satellite) foi desenvolvido através de uma parceria entre Brasil e C
Publicado em: 2005
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8. Metodo de sincronização de cameras de video utilizando a banda de audio
This work proposes and evaluates a novel method for synchronisation of video cameras using the audio band. The method consists in generating and transmitting an audio signal through radio frequency for receivers connected to the microphone input of the cameras and inserting the signal in the audio band. In a software environment, the phase differences among
Publicado em: 2005
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9. Analysis of concrete material through gamma ray computerized tomography
Computerized Tomography (CT) refers to the cross sectional imaging of an object from both transmission or reflection data collected by illuminating the object from many different directions. The most important contribution of CT is to greatly improve abilities to distinguish regions with different gamma ray transmittance and to separate over-lying structures
Brazilian Journal of Physics. Publicado em: 2004-09
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10. Development of a simulator for tomographic images generated by radiation transmission
A computer program to simulate tomographic images generated by transmitted radiation was developed. The algorithm uses a deterministic approach to generate the projections, which supply an existing image reconstruction software. A dispersion associated with the counting statistics is also incorporated into the algorithm, in order to simulate the influence of
Brazilian Journal of Physics. Publicado em: 2004-09
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11. Computerized tomography with high-energy proton beams: tomographic image reconstruction from computer-simulated data
The use of protons instead of X-rays for computerized tomography (CT) studies has potential advantages, especially for medical applications in proton treatment planning. However, the spatial resolution of proton CT is limited by multiple Coulomb scattering (MCS). We used the Monte Carlo simulation tool GEANT4 to study the resolution achievable with different
Brazilian Journal of Physics. Publicado em: 2004-09
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12. Reconstrução tomográfica de imagens utilizando técnicas POCS seqüenciais e paralelas.
In this dissertation four algorithms are presented for the tomographic reconstruction of images using methods denominated POCS - Projections onto Convex Sets, which are the ART - Algebraic Reconstruction Technique, the SIRT - Simultaneous Iterative Reconstructive Technique, the sequencial POCS and parallel POCS. A comparison is made between the reconstructio
Publicado em: 2001