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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.
- AUTOMOTIVE: a case study on AUTOmatic multiMOdal drowsiness detecTIon for smart VEhiclesPublication . Esteves, Telma; Pinto, João Ribeiro; Ferreira, Pedro M.; Costa, Pedro Amaro; Rodrigues, Lourenço Abrunhosa; Antunes, Inês; Lopes, Gabriel; gamito, pedro; Abrantes, Arnaldo; Jorge, Pedro; Lourenço, André; Sequeira, Ana F.; Cardoso, Jaime S.; Rebelo, AnaAs technology and artificial intelligence conquer a place under the spotlight in the automotive world, driver drowsiness monitoring systems have sparked much interest as a way to increase safety and avoid sleepiness-related accidents. Such technologies, however, stumble upon the observation that each driver presents a distinct set of behavioral and physiological manifestations of drowsiness, thus rendering its objective assessment a non-trivial process. The AUTOMOTIVE project studied the application of signal processing and machine learning techniques for driver-specific drowsiness detection in smart vehicles, enabled by immersive driving simulators. More broadly, comprehensive research on biometrics using the electrocardiogram (ECG) and face enables the continuous learning of subject-specific models of drowsiness for more efficient monitoring. This paper aims to offer a holistic but comprehensive view of the research and development work conducted for the AUTOMOTIVE project across the various addressed topics and how it ultimately brings us closer to the target of improved driver drowsiness monitoring.
- Automatic vehicle detection and classificationPublication . Ferreira, Pedro Miguel; Marques, Gonçalo; Jorge, Pedro; Abrantes, Arnaldo; Amador, AntónioThis paper presents a proposal for an automatic vehicle detection and classification (AVDC) system. The proposed AVDC should classify vehicles accordingly to the Portuguese legislation (vehicle height over the first axel and number of axels), and should also support profile based classification. The AVDC should also fulfill the needs of the Portuguese motorway operator, Brisa. For the classification based on the profile we propose:he use of Eigenprofiles, a technique based on Principal Components Analysis. The system should also support multi-lane free flow for future integration in this kind of environments.
- 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.
- Tracking with Bayesian networks: extension to arbitrary topologiesPublication . Jorge, Pedro; Abrantes, Arnaldo; Marques, Jorge S.It was recently proposed an object tracking method, which is able to deal with object occlusions and group tracking, using Bayesian networks. The Bayesian network (BN) tracker has shown promising results in difficult situations but its architecture is limited to a maximum of 2 parents/2 children per node, in order to avoid the combinatorial explosion and difficult network generation procedures from the video signal. This paper addresses the major limitation of the BN tracker and presents a method to generalize the tracker to cope with arbitrary topologies, allowing the tracker to operate in more complex scenes.
- Automatic tracking of multiple pedestrians with group formation and occlusionsPublication . Jorge, Pedro; Abrantes, Arnaldo; Marques, Jorge S.This work addresses the problem of automatic track ing of pedestrians observed by a fixed camera in out door scenes. Tracking isolated pedestrians is not a difficult task. The challenge arises when the track ing system has to deal with temporary occlusions and groups of pedestrians. In both cases it is not possi ble to track each pedestrian during the whole video sequence. However, the system should be able to rec ognize each pedestrian as soon as he/she becomes vis ible and isolated from the group. This paper presents methods to tackle these difficulties. The proposed sys tem is based on a hierarchical approach which allows the application of the same methods for tracking iso lated pedestrians and groups.
- Interoperability among its systems with Its-Ibus frameworkPublication . F. G. Osório, A. Luís; Barata, Manuel; Gonçalves, Carlos; Araújo, P.; Abrantes, Arnaldo; Jorge, Pedro; Gomes, J. Sales; Jacquet, G.; Amador, A.This paper presents and discusses the extended Via-Verde business model from the point of view of the underlying requirements for the virtual business processes. The extension of Via-Verde concept to other services beyond the motorway toll collection has increased the number of independent companies involved. The complex networked scenario resulted on a proposal of an intelligent transport system — interoperability bus (ITS-IBus) (Gomes et. al. 2003) (Osorio, et. al. 2003-a) aiming to promote a generalized interoperability among heterogeneous (multi-vendor) technological subsystems. The ITS-IBus initiative has been developing since then, a reference implementation of a peer-to-peer service based framework with pluggable feature and a set of common agreed interfaces for coupling different technological systems. An important objective is to increase the quality of the offered services by establishing a flexible execution and coordination framework for the collaborative distributed business processes.
- 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.