Percorrer por autor "Felgueiras, Carlos"
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- Advances on Sustainable Development in Higher EducationPublication . Caetano, Nídia; Felgueiras, CarlosSustainable development has been linked to the ecological, economic and social dimensions, and it appears from the outset that it is a complex task to include several very different aspects while planning and projecting. This multi-dimensional feature migrates to education sustainable development that is, as expected, a complex task. Traditional education based on specialization of subjects and unidirectionality of strategies has often proved to be insufficient. The present Track intends to be a space of debate of the challenges posed to Higher Education professionals as strategic partners for the development of different mindsets, able to tackle the real problems.
- An Alternative Way of Teaching Operational Amplifiers Using a Reconfigurable and Expandable KitPublication . Costa, Ricardo; Portela, Paulo; Alves, Gustavo R.; Felgueiras, Carlos; Viegas, ClaraEarly on, students must develop competences by implementing simple or complex electronic circuits with Operational Amplifiers (OpAmps). Traditionally, these skills were mainly developed in laboratory classes, but technology allows us to explore other and complementary ways of aiding students in this achievement. This paper presents a contribution to improve the way OpAmps are included in electronic engineering courses’ curricula. A reconfigurable and expandable kit to teach electronic circuits based on the OpAmp uA741 was designed and implemented. This kit comprises a software application locally interfaced with a hardware platform capable of running in a PC. This platform includes a circuit with the OpAmp uA741 able to reconfigure according to a set of parameters defined by a software application. Its reconfiguration capability also enables the establishment of automatic connections for measuring and for applying signals to a reconfigured circuit, plus the ability to simulate the same or other OpAmp-based circuits. This paper provides an overview about the OpAmp uA741 and its relevance in engineering education. After presenting the kit and make some considerations for its improvement, at the end a brief discussion about its implementation in education according to specific educational strategies and methodologies are provided.
- An educational remote laboratory for controlling a signal conditioning circuit with an LDR sensorPublication . Costa, Ricardo; Bastos, Paulo; Alves, Gustavo R.; Felgueiras, Carlos; Fidalgo, AndréIn the past few years, the technologic evolution of communication and information systems had a major impact in our lives. In education, this evolution broke some geographical barriers, facilitating students’ access to real laboratories using a simple device connected to the Internet, contributing therefore to improve teaching and learning methods. To support this evolution, this paper describes a remote laboratory that provides students’ access to a typical electronic instrumentation system. Through a set of webpages, users can remotely control a light intensity sensed through a Light Dependent Resistor (LDR) sensor connected in an arm of a configurable Wheatstone Bridge (WB), whose output differential voltage are amplified / attenuated by an Instrumentation Amplifier (IA) circuit. Through this laboratory, users are able to control several components of a typical instrumentation system, visualize changes and analyze some measurements, in the same way as they would do in a traditional hands-on laboratory. An overview of the developed remote laboratory and a contextualization within other available solutions are presented in this paper. At the end, some considerations for its adoption in education are described.
- An embedded 1149.4 extension to support mixed-signal debuggingPublication . Felgueiras, Carlos; Alves, Gustavo R.; Ferreira, José M.Debugging electronic circuits is traditionally done with bench equipment directly connected to the circuit under debug. In the digital domain, the difficulties associated with the direct physical access to circuit nodes led to the inclusion of resources providing support to that activity, first at the printed circuit level, and then at the integrated circuit level. The experience acquired with those solutions led to the emergence of dedicated infrastructures for debugging cores at the system-on-chip level. However, all these developments had a small impact in the analog and mixed-signal domain, where debugging still depends, to a large extent, on direct physical access to circuit nodes. As a consequence, when analog and mixed-signal circuits are integrated as cores inside a system-on-chip, the difficulties associated with debugging increase, which cause the time-to-market and the prototype verification costs to also increase. The present work considers the IEEE1149.4 infrastructure as a means to support the debugging of mixed-signal circuits, namely to access the circuit nodes and also an embedded debug mechanism named mixed-signal condition detector, necessary for watch-/breakpoints and real-time analysis operations. One of the main advantages associated with the proposed solution is the seamless migration to the system-on-chip level, as the access is done through electronic means, thus easing debugging operations at different hierarchical levels.
- An overview of the evolution of civil engineering education towards sustainability in PortugalPublication . Silva, Paulo; Caetano, Nídia S.; Felgueiras, CarlosEducation is essential to prepare future professionals, preparing them for the labor market, by providing knowledge and practical experiences. The model that trains these professionals becomes crucial for professionals to adapt to the current needs of this market, which in itself is competitive and dynamic, so it is always in constant change of priorities and needs. It is undeniable that environmental and sustainability issues have become essential aspects in the performance of any business at a global level. Particularly, the concern with sustainability becomes evident in the field of civil engineering, due to the need of optimization of use of resources (raw materials, energy and water), that can have a huge impact on the environment, resulting both from reduction of consumption of resources, and pollutants emissions. Therefore, the MSc courses should have two levels of education on sustainability: at the mul-tidisciplinary level, Higher Education schools should offer courses specifically dedicated to sustainable development and sustainability should be analysed glob-ally; at the disciplinary level, each course should include the basic related concerns with sustainability issues. This work surveys civil engineering courses in Portugal and analyzes how subjects related to SDGs are directly or indirectly present in the respective curricula.
- Analog electronic teaching – a new approach for bipolar transistorsPublication . Felgueiras, Carlos; Santos, Catarina; Alves, Gustavo R.; Fidalgo, André; Pertry, Clovis; Schlichting, Luisa) This work was based in a single individual sample; b) Learning Support Means (LSM) received poor acceptance; c) Other Alternative Support Means are under development; d) For these, a broader test sample was used; e) Preliminary results from this test are encouraging to further pursue this work
- Analysis of Fossil Fuel Energy Consumption and Environmental Impacts in European CountriesPublication . Martins, Florinda; Felgueiras, Carlos; Smitkova, Miroslava; Caetano, NídiaThe use of fossil fuels as the main source of energy for most countries has caused several negative environmental impacts, such as global warming and air pollution. Air pollution causes many health problems, causing social and economic negative effects. Worldwide efforts are being made to avoid global warming consequences through the establishment of international agreements that then lead to local policies adapted to the development of each signing nation. In addition, there is a depletion of nonrenewable resources which may be scarce or nonexistent in future generations. The preservation of resources, which is a common goal of the Circular Economy strategy and of sustainable development, is not being accomplished nowadays. In this work, the calculation of indicators and mathematical and statistical analysis were applied to clarify and evidence the trends, provide information for the decision-making process, and increase public awareness. The fact that European countries do not possess abundant reserves of fossil fuels will not change, but the results of this analysis can evolve in the future. In this work, fossil fuel energy consumption, fossil fuel depletion, and their relationship with other variables, such as energy dependence and share of renewable energy in gross final energy consumption, were analyzed for 29 European countries. Furthermore, it was possible to conclude that many European countries still depend heavily on fossil fuels. Significant differences were not found in what concerns gross inland consumption per capita when the Kruskal–Wallis test was applied. It was possible to estimate that by 2050 (considering Jazz scenario) it will only remain approximately 14% of oil proven reserves, 72% of coal proven reserves and 18% of gas proven reserves. Given the small reserves of European countries on fossil fuels, if they need to use them, they will fast disappear.
- Book of abstracts of ICEER2019: The 6th International Conference on Energy and Environment Research: Energy and Environment: Challenges towards circular economyPublication . Caetano, Nídia de Sá; Borrego, Carlos; Nunes, Maria Isabel da Silva; Felgueiras, CarlosThe 6th edition of the International Conference on Energy and Environment Research, ICEER 2019, took place in the end of July 2019, at the University of Aveiro, Portugal. With most of the participants coming from academia, and a few from the professional field, ICEER series is still growing and attracting increased interest. Energy production, distribution and use are fundamental for the Sustainable Development of nations, showing a clear link between the energy and environment issues. Nevertheless, these matters are frequently dealt with separately, reflecting the way they are taught, and causing strong negative impacts, and hindering progress. With a growing trend in circular economy models applied to common goods production and commercialization, ICEER 2019 had as focus theme the challenges posed by energy and environment research in a circular economy-based model.
- Buildings Sustainability — The Non-Intrusive Load-Identification System ContributionPublication . Felgueiras, Carlos; Cruz, N.; Martins, F.; Martins, R.Buildings are responsible for an important share of the global energy consumed with the associated consequences at economic and environmental level. To overcome this actual concern several objectives were put in perspective, being one of them the energetic performance of systems and appliances. Efficiency depends on working on optimal conditions and user behavior. Monitoring of the energy consumption of each electric load is important but the use of decentralized energy is not feasible at present due to the huge number of loads connected to the electric grid. An alternative consists on the use of a centralized measurement device able to identify loads. This work presents a measurement infrastructure that have, among others, the possibility to make the identification of electrical loads data will be used to improve the energetic performance of households and buildings and increase the sustainability of the energy system.
- Buildings Sustainability: The HVAC ContributionPublication . Felgueiras, Carlos; Santos, Rute; Fonseca, Luís Miguel; Caetano, Nídia SáA very important part of the globally produced energy is consumed in buildings, being an important share frequently used in the HVAC systems. These ones are increasing both in performance and in complexity, taking advantage from the use of the recent advances in mechanical and power electronic devices, particularly in the speed variation field. However the improved efficiency only occurs while the HVAC unit is working in the conditions specified by the manufacturer, otherwise the energy consumption raises to values considerably higher than the nominal ones. The adequate maintenance enforces the system to run on its nominal performance and the contrary has undesirable impact both in the performance and in the system expected life time. Therefore, HVAC field maintenance assumes a very important role in the global building sustainability concept. This work presents some results of an incorrect use of HVAC and the associated electric energy overconsumption that can assume values 50% higher than those that occur when the installation is operated according to the adequate maintenance plan.