Browsing by Issue Date, starting with "2016-12"
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- Fully automatic segmentation of femurs with medullary canal definition in high and in low resolution CT scansPublication . Almeida, Diogo F.; Ruben, Rui; Folgado, João; Fernandes, Paulo R.; Audenaert, Emmanuel; Verhegghe, Benedict; De Beule, MatthieuFemur segmentation can be an important tool in orthopedic surgical planning. However, in order to over- come the need of an experienced user with extensive knowledge on the techniques, segmentation should be fully automatic. In this paper a new fully automatic femur segmentation method for CT images is pre- sented. This method is also able to define automatically the medullary canal and performs well even in low resolution CT scans. Fully automatic femoral segmentation was performed adapting a template mesh of the femoral vol- ume to medical images. In order to achieve this, an adaptation of the active shape model (ASM) tech- nique based on the statistical shape model (SSM) and local appearance model (LAM) of the femur with a novel initialization method was used, to drive the template mesh deformation in order to fit the in-image femoral shape in a time effective approach. With the proposed method a 98% convergence rate was achieved. For high resolution CT images group the average error is less than 1 mm. For the low resolution image group the results are also accurate and the average error is less than 1.5 mm. The proposed segmentation pipeline is accurate, robust and completely user free. The method is ro- bust to patient orientation, image artifacts and poorly defined edges. The results excelled even in CT images with a significant slice thickness, i.e., above 5 mm. Medullary canal segmentation increases the geometric information that can be used in orthopedic surgical planning or in finite element analysis.
- Digital media as a driver of a more inclusive higher educationPublication . Almeida, Ana Margarida; Santos, Rita; Batista, João; Pereira, Dora; Sousa, Célia MariaDigital media may have a fundamental role in promoting more inclusive social and learning experiences, particularly when considering the challenge of widening participation that Higher Education Institutions (HEI) are currently facing. This article briefly overviews recent policies, initiatives and recommendations that address the use of digital media in promoting a more inclusive higher education (HE) system; the review focuses especially on actions involving HE students and that promote innovative uses of digital media solutions that provide flexible delivery models and alternative ways of communicating, helping students from a variety of non-traditional backgrounds and contexts to actively participate and engage with HE in a more open and inclusive approach. The article also presents preliminary results of an exploratory survey on how Portuguese public HEI websites present the challenge of inclusion, namely through digital media. The results of the review show the increasing importance for HE of ensuring open and inclusive student experiences through the use of digital media, although it seems that there is a lack of policies and information widely available about how this can be achieved, especially for publics other than the learners with disabilities or special education needs. Also, the analysis of the HEI websites does not seem to reveal a great concern in presenting HEI as open, flexible and inclusive for all learners, particularly using digital media. Drawing on the revision undertaken and on the collected data, the authors make recommendations for future research and propose an action plan towards the development of a future research project.
- Choosing sheep (Ovis aries) as animal model for temporomandibular joint research: Morphological, histological and biomechanical characterization of the joint discPublication . Angelo, D.F.; Morouço, P.; Alves, N.; Viana, T.; Santos, F.; González, R.; Monje, F.; Macias, D.; Carrapiço, B.; Sousa, R.; Cavaco-Gonçalves, S.; Salvado, F.; Peleteiro, C.; Pinho, M.Preclinical trials are essential to the development of scientific technologies. Remarkable molecular and cellular research has been done using small animal models. However, significant differences exist regarding the articular behavior between these models and humans. Thus, large animal models may be more appropriate to perform trials involving the temporomandibular joint (TMJ). The aim of this work was to make a morphological (anatomic dissection and white light 3D scanning system), histological (TMJ in bloc was removed for histologic analysis) and biomechanical characterization (tension and compression tests) of sheep TMJcomparing the obtained results with human data. Results showed that sheep processus condy-laris and fossa mandibularis are anatomically similar to the same human structures. TMJ dischas an elliptical perimeter, thinner in the center than in periphery. Peripheral area actsas a ring structure supporting the central zone. The disc cells display both fibroblast andchondrocyte-like morphology. Marginal area is formed by loose connective tissue, with somechondrocyte-like cells and collagen fibers in diverse orientations. Discs obtained a tensile mod-ulus of 3.97 ± 0.73 MPa and 9.39 ± 1.67 MPa, for anteroposterior and mediolateral assessment.The TMJ discs presented a compressive modulus (E) of 446.41 ± 5.16 MPa and their maximumstress value ( max) was 18.87 ± 1.33 MPa. Obtained results suggest that these animals should beconsidered as a prime model for TMJ research and procedural training. Further investigationsin the field of oromaxillofacial surgery involving TMJ should consider sheep as a good animalmodel due to its resemblance of the same joint in humans.© 2016 Elsevier Masson SAS. All rights reserved.
- Blind Guide: anytime, anywherePublication . Yánez, Daniel Vera; Marcillo, Diego; Fernandes, Hugo; Barroso, João; Pereira, AntónioEyesight is an important sense that helps humans to avoid dangers and navigate in our world. Blind people usually have enhanced accuracy and sensibility of their other natural senses in order to sense their surroundings. But sometimes this is not enough because the human senses can be affected by external sources of noise or disease. That is why technology has been used to develop many assistive tools. Artifacts like white canes or braille compasses help blind people moving around in the environment. In this article, the use of a system that detects and recognize nearby objects or obstacles is proposed, giving an audible feedback to the user. It is designed as a wireless system in order to be comfortable to be carried by the user. The system helps visual impaired people to move around in indoor or outdoor scenarios. The goals of this blind guide system is to detect obstacles that white canes or dogs cannot, extending its detection range.
- Marketing experiencial: o estudo de 3 hotéis de charme da região centro de PortugalPublication . Marques, Alzira; Dantas, JoséA competitividade das marcas depende, em parte, de as empresas associarem aos produtos e serviços experiências memoráveis, uma vez que os consumidores os compram não só por aquilo que eles fazem mas também por aquilo que eles significam. Os clientes esperam ser influenciados de um modo positivo, emocional e memorável em todos os níveis da sua vivência comercial. É neste contexto que emerge o marketing experiencial, que tem pautado a orientação estratégica do sector da hotelaria, motivo pelo qual o escolhemos para alvo de estudo. Assim, com base no caso de estudo de 3 hotéis de charme na região de Leiria identificámos as práticas de marketing experiencial implementadas e verificámos que estão relacionadas com o nível de satisfação dos clientes e de popularidade dos hotéis, estão também na origem do WOM positivo que desempenha um papel importante na captação de novos clientes.
- Animais nossos Amigos. Dos versos de Afonso Lopes Vieira aos animais de Pedro Anjos TeixeiraPublication . Nobre, Cristina; Cruz, Sara; Carvalho, Vânia; Coelho, MárioFruto de um percurso acidentado e quase centenário, no acervo do Museu de Leiria incluem-se várias peças cuja memória se foi desvanecendo. É a história de algumas dessas peças que pretendemos nesta ocasião reconstituir. Centrámo-nos nas pequenas estátuas de animais, esculpidas em pedra, por Pedro Anjos Teixeira, que se encontram presentemente no Museu e corporizam os animais-personagens da obra Animais Nossos Amigos, de Afonso Lopes Vieira.
- Interfaces alternativas para brinquedos adaptadosPublication . Soares, Marcos; Conniot, Wilson; Gomes, Hugo; Lopes, Nuno VieiraO presente artigo descreve o trabalho desenvolvido durante o ano letivo 2015/2016 no âmbito da unidade curricular de Projeto em Engenharia Eletrotécnica e de Computadores do curso de Licenciatura em EngenhariaEletrotécnica e de Computadores da Escola Superior de Tecnologia e Gestão (ESTG). São apresentadasideias e objetivos, bem como as metodologias de trabalho utilizadas e os protótipos desenvolvidos deforma a tornar a interação de crianças com brinquedos adaptados mais simples e divertida. Em conjuntocom a campanha “Mil Brinquedos Mil Sorrisos” foram definidas algumas estratégias para melhorar esta interaçãoatravés da inovação e melhoramento dos dispositivos já desenvolvidos. Numa primeira abordagem foi efetuada uma pesquisa sobre as interfaces alternativas já existentes para brinquedosadaptados, sobre os requisitos necessários para cada sistema, o funcionamento e consumos energéticosde cada dispositivo e custos associados. Foram criados dois sistemas de interação: um com fios e outro sem fios, sendo este último constituído por dois elementos (interruptor emissor e recetor). Associado a este sistema sem fios, foi também desenvolvida uma aplicação para dispositivos móveis (sistema operativo Android) que permite ativar o brinquedo adaptado a partir de um Smartphone ou Tablet.
- First aid drone for outdoor sports activitiesPublication . Bravo, Gustavo Cedeno; Parra, Diego Marcillo; Mendes, Luis; Pereira, Antonio Manuel de JesusPracticing sports in the outdoors as a way to reduce stress levels, improve health; and even as an incentive to improve social relations, has encouraged more and more people to leave the sedentary lifestyle to perform activities like walking, jogging, hiking, biking, among others. This trend to practice outdoor sport activities was also driven by new technological gadgets (e.g., smartphone whit special apps, fitness trackers and smartwatches) since they allow tracking all the workout values (e.g., pace, speed, distance, duration), vita parameters and signals (e.g., heart rate, temperature and calories burned) and also the exercise route (e.g., geographic coordinates). During outdoors sports activities, independently if these are amateur or professional, the sportsman can suffer accidents, which can result in body injuries, or an unexpected health problem (e.g., heart attack, heatstroke and dehydration) that can limit its mobility or even its conscious state. When this happens, an emergency service should be activated. This is the more important the more remote is the site of the emergency. A solution envisaged to provide emergency care as soon as possible in cross-country sports competitions, even when the land topography is very rough, is proposed in this paper. The base idea is to use a drone that carries a first aid kit (bandages, alcohol, cotton, gauze, water, and other emergency and survival products) and has real-time audio and video communications capabilities.
- Improved numerical methods in reliability analysis of suspension roof jointsPublication . Priadko, I.N.; Mushchanov, V.P.; Bártolo, H.; N.I. Vatin; I.N. RudnievaModern structures require more complex designs. There is an increased need for accurate approaches to assessing uncertainties in loads, geometry, material properties, and operational environments. However, information is scarce on the reliability of suspension roofs together with their joints. There is an urgent need for estimating stress-strain state and reliability of welded joints, so recommendations can be given based on the obtained data. In this paper, reliability of large-span suspension roofs was investigated and a fundamental approach is proposed for reliability determination of these joints at the design phase of suspension rod roofs. In this work, several joints were investigated: supporting joints between rigid threads and external/internal contours, intermediate joints of top /lower chords of supporting threads, as well as joints between vertical/horizontal links and supporting thread of a roof. To measure reliability of joints, logic and probabilistic methods were used conjointly with other methods based on mathematical statistics. The proposed approach can be applied to design of suspension roof systems and help to develop better designs for better safety, quality control and efficiency of these structures, providing economic and social benefits. © Priadko I.N., Mushchanov V.P., Bartolo E., Vatin N.I., Rudnieva I.N., 2016.
- CFD analysis of head and helmet aerodynamic drag to wheelchair racingPublication . Forte, Pedro; Marinho, Daniel A.; Morouço, Pedro; Barbosa, TiagoWheelchair racing, an important event in Paralympics, it requires huge effort from its athletes to overcome the resistive forces. The resistive forces in wheelchair racing are aerodynamic drag and rolling friction. CFD methodology can play a determinant role in aerodynamic analysis. The aim of this study was to analyses the aerodynamic drag at different speeds and attack angles of a human head with a helmet, whilst extrapolating results to better suit the needs of wheelchair racing athletes. Computer Fluid Dynamics methodology was used in this study. A 3D head and helmet scan was obtained from a Paralympics athlete. The 3D model was exported to fluent software generating the aerodynamic drag after numerical simulation. Regardless the velocity, 90° attack angle (subject looking down) presented higher aerodynamic drag (0.732 N) Wheelchair racing athletes should maintain a 0° attack angle (looking forward) mainly at speeds greater than 3.5 m/s.