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- Automatic versus semi-automatic method for the striatum specific uptake ratio quantification based on [I-123]FP-CIT SPECT imagesPublication . Elias, Maria; Jorge, Pedro; Figueiredo, Sérgio; Oliveira, Luís; Pereira, Edgar L.The aim of this work was to implement an automatic application (AA) for the quantification of the striatum transaxial slices based on [I-123]FP-CIT SPECT (Single Photon Emission Tomography) images. A sample of 68 subjects with and without pathology was collected from the nuclear medicine department of the Hospital Particular de Almada. In order to compare the striatum specific uptake ratios (SUR), a semi-automatic application (SAA) was also developed allowing manual adjustments by a specialist operator. The obtained results were compared with the DaTSCAN (R) V4 application, from General Electric Healthcare. The experimental results based on SUR demonstrate that the AA can successfully discriminate the healthy patients from the pathological subjects. Additionally, a strong correlation was verified between the AA and the semi-automatic methods (DaTSCAN (R) V4 and the SAA). These methods also evidence intra and inter-operator variability, suppressed by the AA. The proposed methodology for segmentation and quantification of the striatum transaxial images obtained by [I-123]FP-CIT SPECT demonstrated that the developed application can accurately complement the visual analysis, requiring future optimization.
- Automatic versus semi-automatic method for the striatum specific uptake ratio quantification based on [I-123]FP-CIT SPECT imagesPublication . Elias, Maria; Jorge, Pedro; Figueiredo, Sérgio; Oliveira, Luís; Pereira, Edgar L.The aim of this work was to implement an automatic application (AA) for the quantification of the striatum transaxial slices based on [I-123]FP-CIT SPECT (Single Photon Emission Tomography) images. A sample of 68 subjects with and without pathology was collected from the nuclear medicine department of the Hospital Particular de Almada. In order to compare the striatum specific uptake ratios (SUR), a semi-automatic application (SAA) was also developed allowing manual adjustments by a specialist operator. The obtained results were compared with the DaTSCAN (R) V4 application, from General Electric Healthcare. The experimental results based on SUR demonstrate that the AA can successfully discriminate the healthy patients from the pathological subjects. Additionally, a strong correlation was verified between the AA and the semi-automatic methods (DaTSCAN (R) V4 and the SAA). These methods also evidence intra and inter-operator variability, suppressed by the AA. The proposed methodology for segmentation and quantification of the striatum transaxial images obtained by [I-123]FP-CIT SPECT demonstrated that the developed application can accurately complement the visual analysis, requiring future optimization.
- Multiscale stress analysis in CFRC using microscope image data of carbon fibresPublication . Graça, R. J. R.; Rodrigues, José Alberto; Loja, Amélia; Jorge, PedroComposite materials, are known as strong candidates to improve different kinds of structures. The micromechanical study of these materials is very important, because it may define the best composite characteristics to be used and/or predict more accurately its response. In the present work a multi-stage procedure comprising different fibre contour modelling strategies and a sequent hierarchic multiscale analysis is performed. With this study it is intended to achieve a more realistic characterization of the stresses maximum values for a set of case studies, through the use of fibre geometry data obtained from microscope images of carbon fibre laminated composites. The theoretical circular cross-section is also considered to enable a comparative study among the different situations.
- Aplicação colaborativa em cenário real para animação de um cenário virtualPublication . Gomes, Telmo; Júnior, Carlos; Jesus, Rui; Jorge, PedroAs aplicações mais populares de mistura de cenários reais com cenários virtuais têm sido as aplicações de realidade aumentada e de realidade mista (realidade aumentada + virtualidade aumentada). Este trabalho mistura a realidade com ambientes virtuais numa aplicação colaborativa para duas pessoas. O projeto tem como objetivo o desenvolvimento de uma aplicação para navegação em ambientes virtuais através da interpretação de movimentos reais de uma pessoa. Estes movimentos são capturados por uma câmara, interpretados com algoritmos de processamento de vídeo e transmitidos para a interface de animação e lógica de jogo do Blender [1] (GameLogic [2]). Este artigo descreve a aplicação e apresenta resultados experimentais que ilustram o seu desempenho.
- Integrated vehicle classification systemPublication . Ferreira, Pedro Miguel; Jorge, Pedro; Marques, Gonçalo; Abrantes, Arnaldo; Amador, AntónioThis paper presents an integrated system for vehicle classification. This system aims to classify vehicles using different approaches: 1) based on the height of the first axle and_the number of axles; 2) based on volumetric measurements and; 3) based on features extracted from the captured image of the vehicle. The system uses a laser sensor for measurements and a set of image analysis algorithms to compute some visual features. By combining different classification methods, it is shown that the system improves its accuracy and robustness, enabling its usage in more difficult environments satisfying the proposed requirements established by the Portuguese motorway contractor BRISA.