Browsing by Issue Date, starting with "2015-09"
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- A experiência industrial de Afonso Lopes VieiraPublication . Nobre, CristinaHá indícios de que, por volta de 1914, Afonso Lopes Vieira e um primo tenham feito parte de um grupo de pessoas com vontade de estabelecer uma nova fábrica de vidros, dirigida por António de Magalhães Júnior. A I Guerra não deve ter facilitado as coisas, mas tudo parece indicar que em 1917 a fábrica produzia alguma coisa.
- Augmented Reality and 3D Technologies: Mapping Case Studies in EducationPublication . Cardoso, Teresa; Coimbra, Teresa; Mateus, ArturLearning anywhere, anytime is becoming ever more a daily routine, due to the increasing and recent growth of information and communication technologies. In the last 5 years, their key characteristic and specifically in the use of mobile equipment and software have been their portability, mobility, and network access. The technological development, including software applications available for the implementation of three-dimensional contents, has been following this trend. Hence, it is important to know whether and how these threedimensional contents are being integrated in educational situations, namely, regarding augmented reality and mobile learning. Thus, a synthesis of Portuguese and international research works and case studies on the use of threedimensional augmented reality is chronologically presented along with the evolution of information and communication technologies. The main goal of this knowledge mapping is to contribute to the state of the art in threedimensional augmented reality technologies in education. In addition, it is aimed at framing the creation and implementation of three-dimensional content in higher education, specifically in the field of mathematics. © Springer-Verlag Berlin Heidelberg 2015.
- A real-time platform for collaborative research on Visible Light CommunicationPublication . Ribeiro, Carlos; Figueiredo, Mónica; Alves, Luis NeroThis paper reports the implementation and performance results of a real-time Visible Light Communication platform. The platform uses a high-level software abstraction architecture where the algorithms are developed and tested in MATLAB, using a modular architecture. With this modular approach it is very easy to add/remove blocks, making it amenable to collaboration with other groups with interest in this field, offering a real-time test bed to evaluate the performance of different modules, algorithms and optical front-ends, which is currently not available. The physical layer is based on DCO-OFDM and is implemented in a Xilinx Virtex-6 FPGA. We explore the optical front-end out-of-band bandwidth to transmit, showing the usefulness of adopting OFDM-based modulations schemes for VLC. Our system transmits at 2m over an indoor free space channel with 12MHz bandwidth, with more than 23dB gain difference, using QPSK, thus achieving 24Mbit/s with a BER smaller than the usual 3.8×10-3 limit.
- Persistence of measles antibodies, following changes in the recommended age for the second dose of MMR-vaccine in PortugalPublication . Gonçalves, Guilherme; Frade, João; Nunes, Carla; Mesquita, João Rodrigo; Nascimento, Maria São JoséIn populations vaccinated with two doses of combined measles–mumps–rubella vaccine (MMR), the serum levels of antibodies against measles depend on the vaccination schedule, time elapsed from the last dose and the area-specific epidemiological situation. Variables measuring “schedule” are age at first and second doses of MMR and intervals derived from that. Changes in vaccination schedules have been made in Portugal. The specific objectives of this study were to measure the association between those potential determinants and the concentration of measles-specific IgG antibodies, after the second dose of MMR. Convenience samples of three Portuguese birth cohorts were selected for this study (41, 66 and 60 born, respectively, in 2001–2003, 1990–1993 and 1994–1995). Geometric mean concentrations (GMC) for measles IgG were, respectively, 934, 251 and 144 mIU/ml; p < 0.001). Anti-measles-IgG serum concentration decreased with time since last vaccination (waning immunity) and was not influenced by any other component of vaccination schedule, namely age at vaccination with the second dose of MMR. Waning levels of measles antibodies have been observed elsewhere but not as fast as it was observed in Portuguese birth cohorts in this study. Changes in the vaccination schedules might have to be considered in the future.
- Experience of an International Collaborative Project with First Year Programming StudentsPublication . Paterson, James H.; Karhu, Markku; Cazzola, Walter; Illina, Irina; Law, Robert; Malchiodi, Dario; Maximiano, Marisa; Silva, CatarinaThis paper describes an Erasmus Intensive Programme that used international collaboration as a novel pedagogical approach to teaching programming skills to first-year students in a blended learning context using a mixture of virtual environment and intensive teaching. The experience and outcomes of the Programme are evaluated from the viewpoints of the students and instructors and conclusions are drawn on the value and conduct of international student collaborations.
- Digital sound processing using arduino and MATLABPublication . Silva, Sergio; Soares, Salviano; Valente, Antonio; Marcelino, Sylvain T.Over the last decade, impelled by the huge open source software community support, the low cost Arduino platform presents itself as an alternative for digital sound processing. Although Arduino is generally used for small applications for the artistic and maker community, its built-in Analog to digital converter can be used for sound capturing, processing and reproduction. Equipped with a powerful AVR 8 bit RISC microcontroller, the Arduino, can achieve up to 200kHz with a 10 bit resolution according to the Atmel ATmega328P datasheet that is the AVR core that we are going to focus on this article. Realizing the hardware potential, software suppliers like Matworks or National instruments, have included the Arduino packages on the software accessories of MATLAB and LABView. This work presents some of the sound capabilities and specific limitations of the Arduino platform, enfacing its connection and installation with MATLAB software. A series of examples of the Arduino interface with MATLAB are detail and shown in order to facilitate users initiation of MATLAB and Arduino Digital Sound Processing enhancing education fostering.
- Automatic network configuration in virtualized environment using GNS3Publication . Emiliano, Rodrigo; Antunes, MárioComputer networking is a central topic in computer science courses curricula offered by higher education institutions. Network virtualization and simulation tools, like GNS3, allows students and practitioners to test real world networking configuration scenarios and to configure complex network scenarios by configuring virtualized equipments, such as routers and switches, through each one's virtual console. The configuration of advanced network topics in GNS3 requires that students have to apply basic and very repetitive IP configuration tasks in all network equipments. As the network topology grows, so does the amount of network equipments to be configured, which may lead to logical configuration errors. In this paper we propose an extension for GNS3 network virtualizer, to automatically generate a valid configuration of all the network equipments in a GNS3 scenario. Our implementation is able to automatically produce an initial IP and routing configuration of all the Cisco virtual equipments by using the GNS3 specification files. We tested this extension against a set of networked scenarios which proved the robustness, readiness and speedup of the overall configuration tasks. In a learning environment, this feature may save time for all networking practitioners, both beginners or advanced, who aim to configure and test network topologies, since it automatically produces a valid and operational configuration for all the equipments designed in a GNS3 environment.
- Collaborative Vehicle Self-Localization Using Multi-GNSS Receivers and V2V/V2I CommunicationsPublication . Conde Bento, Luis; Chelim, Rafael; Nunes, UrbanoThis paper presents a collaborative self-localization approach using a multi-GNSS receiver setup and V2V/V2I communications. The purpose is to develop a low-cost alternative (equipment and installation), without compromising the process of localization estimation. The proposed method uses two GPS-receivers installed on the vehicle, disposed longitudinally on the cover (to maximize the distance among receivers) in order to estimate the Yaw and Pitch angles. To estimate the Roll angle, the proposed approach uses information from a receiver on the road infrastructure or on a nearby vehicle using V2V and/or V2I communication (compliant with 802.11p standard). Experimental results revealed that the performance on both absolute positioning and Pitch angle estimation is very high. The method is accurate in Yaw angle estimation enabling acceptable results in heading computation. Therefore the use of this algorithm in risk assessment on crossroads approaching scenarios, is achievable with an affordable setup. The Roll angle estimation can reach satisfactory results if there is a third receiver in the vicinity and in a non-collinear position with respect to the installed onboard receivers.
- Adaptação de Obras Literárias Cabo-Verdianas em Multiformato: Um passo no combate à info-exclusãoPublication . Pina, Maria Teresa Mascarenhas dos Santos; Sousa, Célia Maria Adão de Oliveira Aguiar deA literatura tem discutido a importância da leitura no desenvolvimento cognitivo e na interação social de um individuo. Em Cabo Verde, os profissionais das áreas da educação e da saúde têm argumentado a necessidade de adequar e adaptar os livros para crianças e jovens, para que todos possam ter oportunidades equitativas no processo de aprendizagem. Nesta linha de pensamento, estruturou-se o presente projeto que teve como objetivo adaptar duas obras literárias infantojuvenis adotados pelo Ministério da Educação e Desporto de Cabo Verde (“Cidadão Pikinoti”, da autoria da Comissão Nacional para os Direitos Humanos e Cidadania e “Um País de Pernas para o Ar”, da autoria da Presidência da República de Cabo Verde) em dois formatos acessíveis - Crioulo e signos do Sistema Pictográfico para a Comunicação (SPC). Posteriormente seguiu-se um estudo exploratório do efeito dos livros adaptados em comparação com o seu formato original, nomeadamente no que diz respeito à reação comunicativa das crianças face aos livros. Participaram neste estudo oito crianças com paralisia cerebral e trinta e três alunos do segundo ano de escolaridade de uma turma bilingue de Ponta d’Água, na Cidade da Praia. Os resultados obtidos evidenciaram que os livros adaptados foram estruturadores e facilitadores da comunicação, face aos livros na sua versão original. Esta constatação foi ainda mais evidente na aplicação prática junto das crianças com paralisia cerebral, já que aquando da leitura das histórias na sua versão original, as reações foram praticamente inexpressivas, contrastando com o envolvimento constante destas crianças no processo comunicativo decorrente das histórias em SPC. Relativamente à reação comportamental das crianças da turma bilingue, face ao livro em Crioulo, também foi possível identificar uma maior participação e dinâmica dos alunos do que os que tiveram contacto com a sua versão em Português. Face aos resultados obtidos, constata-se a necessidade urgente de adaptar os materiais didáticos existentes em Cabo Verde, adequando-os a uma intervenção que vá ao encontro das capacidades e necessidades de todas as crianças e jovens, de forma a melhorar o seu processo comunicativo e as aprendizagens que dele decorrem.
- Earthquake loss estimation for the Kathmandu ValleyPublication . Chaulagain, Hemchandra; Rodrigues, Hugo; Silva, Vitor; Spacone, Enrico; Varum, HumbertoKathmandu Valley is geologically located on lacustrine sediment basin, characterized by a long history of destructive earthquakes. The past events resulted in large structural damage, loss of human life’s and property, and interrupted the social development. In recent years, the earthquake risk in this area has significantly increased due to uncontrolled development, poor construction practices with no earthquake safety provisions, and lack of awareness amongst the general public and government authorities. In this context, this study explores the realistic situation of earthquake losses due to future earthquakes in Kathmandu Valley. To this end, three municipalities: (a) Kathmandu Metropolitan City, (b) Lalitpur Sub-Metropolitan City and (c) Bhaktapur Municipality are selected for a case study. The earthquake loss estimation in the selected municipalities is performed through the combination of seismic hazard, structural vulnerability, and exposure data. Regarding the seismic input, various earthquakes scenario considering four seismic sources in Nepal are adopted. For what concerns the exposure, existing literature describing the construction typologies and data from the recent national census survey of 2011 are employed to estimate ward level distribution of buildings. The economic losses due to the earthquake scenarios are determined using fragility functions. Finally, the ward level distribution of building damage and the corresponding economic losses for each earthquake scenario is obtained using the OpenQuake-engine. The distribution of building damage within the Kathmandu Valley is currently being employed in the development of a shelter model for the region, involving various local authorities and decision makers.