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- Adapting portuguese architecture to former african colonies climate conditionsPublication . Ferreira, Ana Vaz; Silva, J.A. Mendes daThe Portuguese architecture is borderless due to the colonialism period. Many African countries can testify this influence and the cities still sprawling around remaining old buildings. These constructions are characterized by using local resources and adapting Portuguese architecture to the climatic characteristics and answering local natural hazards. The work developed presents a systematic approach about the constructive changes, identifying the solutions adopted for answering climatic demands. The passive solar systems used were categorized and some examples were selected according to examples found in African cities with Portuguese influence as Beira (Mozambique), Lubango, Namibe and Luanda (Angola) and Praia (Cape Verde). This analysis encompasses strategies to improve thermal behavior of buildings, as ventilation trough the analysis of ventilated roofs or windows geometry, shadowing devices as large eaves, brises and second facades, among other issues. The local construction was also analyzed in order to find out traditional techniques for cooling buildings in a natural way.
- Adaptive error control coding for a mobile broadband systemPublication . Torres, Paulo; Caseiro, Carlos; Gusmão, AntónioThe Mobile Broadband System (MBS) under research in Europoe aims at offering to mobile users an ATM-based radio access to the future integrated broadband communications network. It is well known that a high-quality transmission channel can be assumed within the fixed broadband network; however, this is far from being expected in the radio links of the future mobile system. This paper is concerned with the design of an error control coding scheme for a first stage of MBS implementation. The proposed scheme is a very flexible, hybrid one, which is based on the concatenation of a convolutional inner code, and a Reed-Solomon outer code, and combines ARQ and FEC features in an adaptive manner, under an implicit evaluation of the channel state. It is powerful enough to cope with poor channel conditions and is compatible with both ATM characteristics and those of a wide range of services (including required BER below lo-' with a delay of a few ms). A set of simulation results illustrates the advantages of the proposed error control coding scheme.
- Algae in acid mine drainage and relationships with pollutants in a degraded mining ecosystemPublication . Gomes, Patrícia; Valente, Teresa; Albuquerque, M.T.D.; Henriques, Renato; Flor-Arnau, Núria; Pamplona, Jorge; Macías, FelipeAcid mine drainage represents an extreme environment with high concentrations of potentially toxic elements and low pH values. These aquatic habitats are characterised by harsh conditions for biota, being dominated by acidophilic organisms. The study site, São Domingos mine, located in one of the largest metallogenetic provinces in the world, the Iberian Pyrite Belt, was closed without preventive measures. To identify the algae species and understand the relationships with abiotic parameters of the ecosystem, water and biological material were collected and analysed. Digital terrain models were obtained with an unmanned aerial vehicle for geomorphological and hydrologic characterisation of the mine degraded landscape. The results show two types of algal colours that seem to represent different degrees of photosynthetic activity. Optical and scanning electron microscopy revealed 14 taxa at the genus level, divided into eight classes. The genus Mougeotia is the most abundant multicellular algae. With respect to unicellular algae, diatoms are ubiquitous and abundant. Abiotic analyses expose typical features of acid mine drainage and support an inverse relationship between chemical contamination and biological diversity. Factorial correspondence analysis indicates three groups of attributes and samples by their relationship with specific toxic elements. This analysis also suggests a close association between Spirogyra and Pb, together composing a structurally simple ecosystem. The highest contamination in the river system is related to the hydrologic patterns obtained from photogrammetric products, such as the digital surface model and flow map accumulation, indicating the input of leachates from the section having the finest sulfide-rich wastes. Information about the algae community and their association with flow patterns of toxic elements is a relevant tool from a biomonitoring perspective.
- Aligning software engineering teaching strategies and practices with industrial needsPublication . Metrôlho, J.C.M.M.; Ribeiro, Fernando Reinaldo; Graça, Paula; Mourato, Ana; Figueiredo, David; Vilarinho, HugoSeveral approaches have been proposed to reduce the gap between software engineering education and the needs and practices of the software industry. Many of them aim to promote a more active learning attitude in students and provide them with more realistic experiences, thus recreating industry software development environments and collaborative development and, in some cases, with the involvement of companies mainly acting as potential customers. Since many degree courses typically offer separate subjects to teach requirements engineering, analysis and design, coding, or validation, the integration of all these phases normally necessitates experience in a project context and is usually carried out in a final year project. The approach described in this article benefits from the close involvement of a software house company which goes beyond the common involvement of a potential customer. Students are integrated into distributed teams comprising students, teachers and IT professionals. Teams follow the agile Scrum methodology and use the OutSystems low-code development platform providing students with the experience of an almost real scenario. The results show that this approach complements the knowledge and practice acquired in course subjects, develops the students’ technical and non-technical skills, such as commitment, teamwork, and communication, and initiates them in the methodologies and development strategies used in these companies. The feedback from the teachers involved, software companies and students was very positive.
- An analytical approach to the ventilation effectiveness of mediterranean buildings: case study: existing residential building, PortugalPublication . Salehi, Atefeh; Torres, Isabel; Ferreira, Ana VazBuilding airtightness assumes an important role in the energy saving and the indoor thermal comfort. Ventilation rates bring significant impacts on energy usage in the constructions and indoor contaminant concentrations and also setting them as the key parameters in building performance. Ventilation rate have been measured in building for a long time, and there are some developed measurement methodologies related to it in the research domains. However, most of the investigations in recent years have been done usually in the cold climate conditions, while Mediterranean construction are not deeply investigated in the literature. In this paper, the authors present the obtained results of an experimental research which is carried out on the Portuguese residential buildings. The investigation is done by fan pressurization methods, also known as “Blower Door Test (BDT)” as the measurement method as well as Design Builder (DB) as the simulation software. The airtightness measurement of the existing buildings and the influence of air leakage on energy consumption and indoor comfort in different Portuguese construction typologies are focused on the aim of the research. The important parameters of the building such as whole-building air change rates, building infiltration rates, and ventilation effectiveness rate in the residential building are also considered in this research.
- An approach using a low-code platform for retraining professionals to ICTPublication . Metrôlho, J.C.M.M.; Araújo, Ricardo; Ribeiro, Fernando Reinaldo; Castela, NunoInformation and Communications Technology is a growing area with a growing demand for employees. However, there is a shortage of professionals in this area and integrated strategies are required to foster the access of more people to these areas and provide training to develop the necessary skills. In this paper we present a short course that was designed to retrain unemployed people, mainly with already a higher education level in the area of the science technology engineering and math (STEM), to be Information and communications technology (ICT) professionals. After this training, trainees will have the opportunity to significantly increase the likelihood of being able to obtain employment in ICT areas. The course described involves public entities (including a higher education institution) and a private company, which is also a demonstration of synergies between academia and business. In the paper, the context that led to the appearance of the course, the fundamentals that supported the syllabus design, the partners involved, the objectives of the several subjects, the profile of the trainees and the results already achieved are described. To explain the fundamentals of the course syllabus we explain the most original features of the course regarding the usefulness of taking advantage of the abstraction allowed by the new low-code platforms, what seem to be appropriate and facilitator for retraining professionals from STEM to ICT. This approach, using a low code platform for retraining professionals to ICT, presents in our point of view, advantages over other approaches. In short, in the paper we intend to share the work done during the design and follow-up of the course, as well as the preliminary results obtained in the meantime.
- An Eco-Energetic performance comparison of dehumidification systems in High-Moisture indoor environmentsPublication . Santos, Alexandre F.; Gaspar, Pedro Dinis; Souza, Heraldo J.L.; Caldeira, J.M.L.P.; Soares, V.N.G.J.This study discusses the choice of dehumidification systems for high-moisture indoor environments, such as indoor swimming pools, supported by an eco-energetic performance comparison. Initially, the causes of the high relative humidity and condensation in these spaces are reported, as well as the available dehumidification technologies. Two different solutions are described: desiccant wheel dehumidification and re-cooling. The energy demand required by a refrigeration system is lower than the desiccant wheel; however, the former system requires less maintenance and does not require refrigerant fluid. An eco-energetic comparison is performed between the two systems in two countries with different energy matrices (Brazil and USA). In Brazil, the desiccant wheel is the best choice for the past 10 years, with a predicted 351,520 kgCO2 of CO2 emissions, which is 38% lower than the refrigeration system. In the USA, the best option is the refrigeration system (1,463,350 kgCO2), a 12% more efficient option than desiccant wheels. This model can be considered for energy and CO2 emissions assessment, predicting which system has better energy efficiency and lower environmental impact, depending on the refrigerant type, location and environmental conditions.
- An industry 4.0 self description information model for software components contained in the administration shellPublication . Neto, Luís; Gonçalves, Gil; Torres, Pedro; Dionísio, Rogério Pais; Malhão, SérgioIndustry 4.0 is the movement towards a fourth industrial revolution that will consist in the digitization and integration of all value chain. In Europe, this movement is led by the German RAMI 4.0 (Reference Architecture for Industry 4.0) proposal, which is attracting a lot of attention from industry, academia and other practitioners. Under the RAMI 4.0 scope there is an Administration Shell proposal to abstract physical and logical assets in a standardized way. Once abstracted, assets become Industry 4.0 Components and can be fully integrated in the Cyber Physical Production System or value chain. This work focuses on the utilization of software components within the Administration Shell. There is a necessity to represent software components and their relation to industrial asset. Therefore, control and monitoring applications involving software components and other assets can be represented in compliance with the I4.0 Component Model. To address this necessity the Smart Object Self Description information model is proposed and applied to a real case study scenario.
- An opportunistic routing solution to monitor isolated elderly people in rural areasPublication . Jesús-Azabal, Manuel; Berrocal-Olmeda, Javier; García-Alonso, José; Soares, V.N.G.J.; Galán-Jiménez, JaimeCountries are experiencing a global population ageing. It is estimated that the percentage of third age people will notably increase in next decades, implying a difficult challenge to society. Rural areas are the most affected locations by these conditions. Currently, small vil- lages are facing an increasing ageing of population where almost 40% of inhabitants are over 65. Medical needs are one of the most relevant aspects in this context. This factor, in conjunction with other reasons such as loneliness, motivates technological solutions. Despite this, Inter- net is not accessible from rural and low income areas, due to the lack of interest from the operator side to invest in these locations. In this paper, an opportunistic routing solution based on BLE is proposed, with the aim of monitoring loneliness population in order to detect potential emergencies.
- Análise dos critérios de classificação dos edifícios nas regulamentações de segurança contra incêndios nos Estados do BrasilPublication . Minervino, Bernardete de Lourdes; Santos, C.C.; Von Krüger, Paulo Gustavo; Rodrigues, João PauloDiante da variedade de legislações de segurança contra incêndio aplicadas no Brasil, é comum encontrar divergências nos parâmetros determinados em cada um dos 27 estados da federação. Elaborar um projeto de incêndio já é uma atividade que exige considerar uma imensa gama de características normativas e funcionais. Elaborar projetos diferentes em dois ou mais estados da federação é uma tarefa ainda mais complexa, uma vez que os parâmetros e as exigências mudam de um estado para o outro. Neste estudo será apresentada uma análise das divergências encontradas nas legislações estaduais, no que se refere ao dimensionamento dos sistemas de segurança contra incêndio e será feita uma proposta de ajuste para os quesitos de classificação de destinação das edificações. O objetivo é sugerir um início para o processo de padronização dos parâmetros de segurança contra incêndio.