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Item100 km-Ultralong Raman Fiber Laser using a Distributed Rayleigh Mirror for Sensing Applications( 2012) Manuel Joaquim Marques ; Hugo Fidalgo Martins ; Orlando Frazão
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Item2012 Survey of Portuguese TTOs( 2012) Aurora Teixeira ; J. Jarrett
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Item2017 Wireless Days, Porto, Portugal, March 29-31, 2017( 2017) Manuel Ricardo ; Campos,Rui ; Ruela,Jose ; Ricardo Morla ; Teixeira,Filipe ; Luís Manuel Pessoa ; Salgado,Henrique
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Item250 km ultra long sensor system based on a Fiber Loop Mirror interrogated by an OTDR( 2011) M. Lopez-Amo ; José Manuel Baptista ; José Luís Santos ; Orlando Frazão ; M. Bravo
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Item2D computational modeling of optical trapping effects on malaria-infected red blood cells( 2017) Joana Isabel Paiva ; Ribeiro,RSR ; Pedro Jorge ; Carla Carmelo Rosa ; Guerreiro,A ; João Paulo CunhaA computational method for optical fiber trapping of healthy and Malariainfected blood cells characterization is proposed. A trapping force relation with the infection stage was found, which could trigger the development of a diagnostic sensor. © OSA 2017.
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Item2D-Interval Predictions for Time Series( 2011) Luís Torgo ; Orlando Shigueo Junior
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Item2DCPackGen: A problem generator for two-dimensional rectangular cutting and packing problems( 2014) Elsa Marília Silva ; José Fernando Oliveira ; Waescher,GCutting and packing problems have been extensively studied in the literature in recent decades, mainly due to their numerous real-world applications while at the same time exhibiting intrinsic computational complexity. However, a major limitation has been the lack of problem generators that can be widely and commonly used by all researchers in their computational experiments. In this paper, a problem generator for every type of two-dimensional rectangular cutting and packing problems is proposed. The problems are defined according to the recent typology for cutting and packing problems proposed by Wascher, Haussner, and Schumann (2007) and the relevant problem parameters are identified. The proposed problem generator can significantly contribute to the quality of the computational experiments run with cutting and packing problems and therefore will help improve the quality of the papers published in this field.
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Item2nd Symposium on Languages, Applications and Technologies, SLATE 2013, June 20-21, 2013 - Porto, Portugal( 2013) José Paulo Leal ; Ricardo Rocha ; Simões,A
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Item3 DoF/6 DoF Localization System for Low Computing Power Mobile Robot Platforms( 2015) Carlos Miguel Costa ; Héber Miguel Sobreira ; Armando Sousa ; Germano Veiga
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Item3-D Position Estimation from Inertial Sensing: Minimizing the Error from the Process of Double Integration of Accelerations( 2013) Neto,P ; Norberto Pires,JN ; António Paulo MoreiraThis paper introduces a new approach to 3-D position estimation from acceleration data, i.e., a 3-D motion tracking system having a small size and low-cost magnetic and inertial measurement unit (MIMU) composed by both a digital compass and a gyroscope as interaction technology. A major challenge is to minimize the error caused by the process of double integration of accelerations due to motion (these ones have to be separated from the accelerations due to gravity). Owing to drift error, position estimation cannot be performed with adequate accuracy for periods longer than few seconds. For this reason, we propose a method to detect motion stops and only integrate accelerations in moments of effective hand motion during the demonstration process. The proposed system is validated and evaluated with experiments reporting a common daily life pick-and-place task.
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Item300 km-Ultralong Raman Fiber Lasers using a Distributed Mirror for Sensing Applications( 2011) Manuel Joaquim Marques ; Hugo Fidalgo Martins ; Orlando FrazãoH. Martins, M. B. Marques, O. Frazão, 300 km-Ultralong Raman Fiber Lasers using a Distributed Mirror for Sensing Applications, Opt. Express, 19 (19), 18149-18154, September 2011.
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ItemA 3D low-cost solution for the aesthetic evaluation of breast cancer conservative treatment( 2014) Hélder Filipe Oliveira ; Jaime Cardoso ; Magalhães,A ; Cardoso,MJBreast cancer conservative treatment (BCCT) is now the preferred technique for breast cancer treatment. The limited reproducibility of standard aesthetic evaluation methods led to the development of objective methods, such as the software tool Breast Cancer Conservative Treatment.cosmetic results (BCCT.core). Although results are satisfying, there are still limitations concerning complete automation and the inability to measure volumetric information. With the fundamental premise of maintaining the system a low-cost tool, this work studies the incorporation of the Microsoft Kinect sensor in BCCT evaluations. The aim is to enable the automatic joint detection of prominent points, both on depth and RGB images. Afterwards, using those prominent points, it is possible to obtain two-dimensional and volumetric features. Finally, the aesthetic result is achieved using machine learning techniques converted automatically from the set of measures defined. Experimental results show that the proposed algorithm is accurate and robust for a wide number of patients. In addition, comparing with previous research, the procedure for detecting prominent points was automated. © 2013 © 2013 Taylor & Francis.
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Item3D lung nodule candidate detection in multiple scales( 2015) Novo,J ; Goncalves,L ; Ana Maria Mendonça ; Aurélio CampilhoLung cancer is mainly diagnosed by the identification of malignant nodules in the lung parenchyma. For that purpose, the identification of all the possible structures that could be suspicious of lung nodules became a crucial task in any lung cancer computer aided diagnosis (CAD) system. In this paper, a new approach for lung nodule candidate identification is proposed. This method uses a 3D medialness Hessian-based filtering to identify round shape structures that could be identified as nodules. This technique, that demonstrated its accuracy in lung vesselness extraction, provides clearer candidates than other approaches, providing less response in the presence of noise artifacts and returns a better continuity in vessels, mostly responsible for false positives. That way, they will be better distinguishable from the nodules in posterior analysis. This approach was validated in 120 scans from the LIDC/IDRI image database. They include 212 nodules with diameters in the range 3 mm to 30 mm. The results demonstrate that our approach is capable of identifying most of the nodules and include less false positives than other approaches, facilitating a posterior task for false positive removal.
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Item3D mapping of choroidal thickness from OCT B-scans( 2018) Simão Pedro Faria ; Penas,S ; Mendonça,L ; Silva,JA ; Ana Maria MendonçaThe choroid is the middle layer of the eye globe located between the retina and the sclera. It is proven that choroidal thickness is a sign of multiple eye diseases. Optical Coherence Tomography (OCT) is an imaging technique that allows the visualization of tomographic images of near surface tissues like those in the eye globe. The automatic calculation of the choroidal thickness reduces the subjectivity of manual image analysis as well as the time of large scale measurements. In this paper, a method for the automatic estimation of the choroidal thickness from OCT images is presented. The pre-processing of the images is focused on noise reduction, shadow removal and contrast adjustment. The inner and outer boundaries of the choroid are delineated sequentially, resorting to a minimum path algorithm supported by new dedicated cost matrices. The choroidal thickness is given by the distance between the two boundaries. The data are then interpolated and mapped to an infrared image of the eye fundus. The method was evaluated by calculating the error as the distance from the automatically estimated boundaries to the boundaries delineated by an ophthalmologist. The error of the automatic segmentation was low and comparable to the differences between manual segmentations from different ophthalmologists. © 2018, Springer International Publishing AG.
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Item3D Model for Aesthetic Objective Evaluation after Breast Cancer Surgery using Infrared Laser Projector( 2011) Jaime Cardoso ; André T. Magalhaes ; Hélder Filipe Oliveira ; João Soares ; Anténio José Moura ; Maria João Cardoso
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Item3D Models for Leg Prothesis - The first step to measure the stub's fitting into a prosthetic device( 2012) Pedro Costa ; Hélder Filipe Oliveira ; Filipe Magalhães ; Frederico Carpinteiro
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ItemA 3D multimodal approach to precisely locate DBS electrodes in the basal ganglia brain region( 2015) Nádia Moreira Silva ; Rozanski,VE ; João Paulo CunhaDeep Brain Stimulation (DBS) is the effective surgical treatment for drug-refractory movement disorders. In order to improve the therapeutic outcome precise anatomic location of electrodes must be achieved. Thus, neurologists can achieve better clinical decisions and take a more careful selection of the best stimulation parameters for DBS. In this paper, we present a system that accurately obtains the 3D positions of DBS electrodes relative to anatomical structures. The latter is based on the segmentation of deep brain structures and on a multimodal imaging approach. In this study, we examined 16 patients undergoing DBS (8 with Parkinson's disease and 8 with dystonia). A 'neuroscientist friendly' graphic user interface (GUI) was designed to support the processing pipeline to precisely detect the electrodes from the DBS lead. Using this system, we obtained the electrodes position and compared them with the ones manually calculated by an experienced physician. The differences observed were less than a voxel size for 89.9% of the cases and the automated procedure takes less 97.5% time than the manual procedure (1min vs 40min). The resulting masks were congruent in shape and position with the corresponding areas in the individuals' space. Using our automatic segmentation pipeline, clinicians save 77% of their time when compared with a manual segmentation (1.20min vs 5.26min). Both structures and electrodes masks were warped to the MNI space in order to provide a common reference space, for the clinical interpretations. © 2015 IEEE.
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Item3D Multimodal Visualization of Subdural Electrodes with Cerebellum Removal to Guide Epilepsy Resective Surgery Procedures( 2014) Nádia Moreira Silva ; Rego,R ; João Paulo CunhaPatients with medically refractory epilepsy may benefit from surgical resection of the epileptic focus. Subdural electrodes are implanted to accurately locate the seizure onset and locate the eloquent areas to be spared. However, the visualization of the subdural electrodes may be limited by the current methods. The aim of this work was to assist physicians in the localization of subdural electrodes in relation to anatomical landmarks using co-registration methods and by removing the cerebellum from MRI images. Three patients with refractory epilepsy were studied, in whom subdural electrodes were implanted. All electrodes were correctly localized in a 3D view over the cortex and their visualization was improved by the removal of cerebellum. This method promises to be useful in the optimization of the surgical plan.
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Item3D Reconstruction of Body Parts Using RGB-D Sensors: Challenges from a Biomedical Perspective( 2014) Costa,P ; Zolfagharnasab,H ; João Pedro Monteiro ; Cardoso,JS ; Hélder Filipe Oliveira
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ItemA 3D Simulation Framework for Safe Ambient-Assisted Home Care( 2011) José Manuel Torres ; Ricardo Morla ; Rui Moreira ; Pedro Sobral ; Carlos Velasquez ; Christophe Soares