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- 2024 U.S. presidential elections: An event study for U.S. and non-U.S. fossil fuel and renewable listed firmsPublication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, NunoThis study examines the short-term market effect of Donald Trump' victory in the 2024 US presidential election on largest US and non-US listed worldwide fuel fossil and renewable firms. Employing an event study methodology, we observe a negative and statistically significant stock price reaction for worldwide renewable listed firms. An analysis by economic zones reveals the existence of negative abnormal returns for renewable energy firms in the US, Europe, India and in the rest of the world. In the case of China, abnormal returns are not statistically significant. With respect to worldwide fossil fuel listed firms, abnormal returns are generally not statistically significant. However, regarding US firms, we observe positive and statistically significant abnormal returns. These abnormal returns are explained by the change of US energy policy (pro-oil and gas policy) and the expected cut in subsidies and lower profitability of investments in green energies. Finally, our study provide insight into which firm-specific characteristics emerge as value drives around US presidential elections. The results show that despite the change in environmental policy in the US, favourable to fossil energy, the stock markets reward firms with high environmental ratings. Overall, our results indicate that 2024 US presidential election, for implying a change in US energy policy, has relevant policy implications for energy listed firms.
- 5th Symposium of Applied Science for Young Researchers: ProceedingsPublication . Fernandes, Florbela P.; Torres, Helena; Pinto, Pedro; Malta, SilvestreThis document presents the proceedings of the 5th Symposium of Applied Science for Young Researchers – SASYR 2025. This scientific event welcomed scientific works on the topics covered by the following four research centers: – CeDRI (from IPB, Instituto Politécnico de Bragança) – 2Ai (from IPCA, Instituto Politécnico do Cávado e do Ave) – GECAD (from IPP, Instituto Politécnico do Porto) – ADiT-lab (from IPVC, Instituto Politécnico de Viana do Castelo) The primary objective of SASYR 2025 is to create a welcoming and relaxed environment for young researchers to present their work, discuss recent findings, and explore new ideas. In this way, this event offers an opportunity for the CeDRI, 2Ai, GECAD, and ADiT-lab research communities to leverage synergies and promote collaborations, thereby enhancing the quality of their research. The SASYR 2025 took place at Instituto Politécnico de Viana do Castelo, Viana do Castelo, Portugal, on 2 July 2025.
- A cibersegurança e tendências emergentesPublication . Fernandes, Arnilde Rita Costa; Lopes, Isabel MariaNum mundo onde a tecnologia tem estado em constante evolução de forma exponencial, seguido do aumento de aparelhos conectados, a sociedade tem se mostrado submissa as tecnologias, e vê-se um grande aumento da vulnerabilidade da cibersegurança por parte das pessoas e entidades, constituindo assim um número acrescido de ciberataques por parte dos hackers, uma vez que não sabem como se proteger devidamente contra esses ataques, tornando-se assim alvos principais. Desta forma, torna-se importante encontrar uma forma de mitigar esses ataques, implementando assim tendências emergentes como a Inteligência Artificial, Blockchain e Internet das Coisas, para poder de alguma forma mitigar a vulnerabilidade da segurança. Com esse intuito, esta dissertação tem como principal objetivo, fazer a análise do panorama atual da cibersegurança, explorar as tendências emergentes que podem ser mais eficazes para mitigar os riscos cibernéticos, e avaliar os desafios que vêm com a implementação da cibersegurança nas organizações. A metodologia de pesquisa utilizada foi a mista, sendo qualitativa com base na revisão bibliográfica, através de artigos científicos, relatórios e fontes de domínio público, quantitativa com base num inquérito que foi dirigido a um determinado grupo de pessoas e posteriormente aplicação de técnicas de Machine learning, especificamente o algoritmos de árvore de decisão para análise preditiva dos dados recolhidos. Os resultados foram tratados e analisados de forma a contextualizar as respostas com o facto das pessoas e profissionais de TI se encontrarem informadas sobre as principais ameaças cibernéticas e como se devem proteger das mesmas, e analisar como os mesmos percebem os desafios e soluções da segurança digital.
- A Comparison of PID Controller Architectures Applied in Autonomous UAV Follow up of UGVPublication . Bonzatto Junior, Luciano; Berger, Guido S.; Braun, João A.; Pinto, Milena F.; Santos, Murillo Ferreira dos; Oliveira Júnior, Alexandre de; Nowakowski, Marek; Costa, Paulo; Wehrmeister, Marco A.; Lima, JoséThe cooperation between Unmanned Aerial Vehicles (UAVs) and Unmanned Ground Vehicles (UGVs) has brought new perspectives and e!ectiveness to production and monitoring processes. In this sense, tracking moving targets in heterogeneous systems involves coordination, formation, and positioning systems between UGVs and UAVs. This article presents a Proportional-Integral-Derivative (PID) control strategy for tracking moving target operations, considering an operating environment between a multirotor UAV and an indoor UGV. Di!erent PID architectures are developed and compared to each other in the Gazebo simulator, whose objective is to analyze the control performance of the UAV when used to track the ground robot based on the identification of the ArUco fiducial marker. Computer vision techniques based on the Robot Operating System (ROS) are integrated into the UAV’s tracking system to provide a visual reference for the aircraft’s navigation system. The results of this study indicate that the PD, Cascade, and Parallel controllers showed similar performance in both trajectories tested, with the Parallel controller showing a slight advantage in terms of mean error and standard deviation, suggesting its suitability for applications that prioritize precision and stability.
- A Practical Approach to Teaching Differential Robot Control Using a Goal-to-Goal InterfacePublication . Amorim, Johann S.J. C. C.; Moraes, Camile A.; Neto, Accacio F. dos; Amorim, Josef G. J. C. C.; Santos, Patricia S.; Haddad, Diego; Pinto, Milena F.; Lima, JoséThis paper presents an interface to assist students in performing robot controllers. This application is designed to stabilize the movement of a goal-to-goal robot. The primary objective is to enhance the learning experience by offering an easy application that showcases the robot’s behavior based on its kinematic model. The paper outlines the various stages involved in developing and testing this simple interface, including a study of the kinematics of differential robots. It discusses the discrete- time equations for goal-to-goal behavior, the data required to obtain the controller, the application of the controller in a discrete microcontroller, and the development of code to simulate the robot’s behavior. The results show the developed interface and the possible outcomes through the use of this application in control classes.
- A prototype to enhance academic attendance using BLE beaconsPublication . Simas, Sily; Oliveira, Pedro Filipe; Matos, PauloThis project addresses the prototyping and application of an attendance control solution in an academic context, using Beacons. The introduction highlights the importance of effectively managing student attendance to ensure active participation in educational activities and provide insights into student engagement. BLE Beacons technology is compared to other RF signaling technologies, highlighting its advantages in terms of range, power consumption, cost, frequency, and data rate. BLE Beacon is chosen as the preferred technology due to its combination of adequate range, low power consumption, affordable cost, compatibility, security, and flexibility. The results section presents Estimote Beacons as devices used, highlighting their advanced features and techniques used, such as proximity and triangulation, to determine student presence. A visual summary of the project is presented in a flowchart that illustrates the operating processes of each stage. This solution promises to significantly improve the efficiency, safety, and quality of the academic environment, while simplifying the attendance recording process and providing valuable insights into student behavior.
- A Study of the determining factors in the adoption of electric vehicles by consumersPublication . Gonçalves, Miguel Francisco Pimenta; Vaz, Clara B.A crescente preocupação ambiental e o rápido avanço da tecnologia têm impulsionado significativamente a adoção de veículos elétricos (VEs) e híbridos plug-in, marcando um momento de transformação no setor dos transportes. Esta dissertação visa identificar os principais fatores que influenciam as decisões dos consumidores na adoção de veículos elétricos. O estudo baseia-se numa amostra de 297 inquiridos residentes em Portugal e recorre a uma abordagem quantitativa para analisar as suas percepções e comportamentos. Os resultados demonstram que a adoção de VEs é fortemente influenciada por factores financeiros, nomeadamente o elevado custo inicial de aquisição e a importância de incentivos governamentais, como subsídios e isenções fiscais. O acesso à infraestrutura de carregamento revelou-se igualmente um fator crítico, moldando a confiança dos consumidores na utilização destes veículos. Adicionalmente, características demográficas, como níveis de rendimento mais elevados e a residência em áreas urbanas, demonstraram ter um impacto significativo na probabilidade de adoção. Curiosamente, embora os benefícios ambientais dos VEs sejam amplamente reconhecidos, a sua influência nas decisões de compra revelou-se inferior à dos fatores financeiros e infraestruturais. Este estudo sublinha a necessidade de políticas públicas direcionadas e de investimentos estratégicos para ultrapassar as barreiras financeiras e logísticas enfrentadas pelos potenciais utilizadores de veículos elétricos. Ao melhorar a infraestrutura e oferecer incentivos bem estruturados, será possível acelerar a transição para um sistema de mobilidade mais sustentável e ambientalmente responsável.
- Acceleration of the ATLAS-CERN calorimeter data preparation with GPUsPublication . Sereniski, Gabriela Paola; Muiño, Patricia Conde; Rufino, José; Gonçalves, Rogério AparecidoThe High-Luminosity Large Hadron Collider (HL-LHC) will deliver substantially higher numbers of simultaneous proton-proton collisions (events), increasing the volume and frequency of detector readouts and placing growing demands on the ATLAS calorimeter (sub-detectors that measure energy deposits from particle showers) data-preparation pipeline. Bytestream decoding is the first step of this pipeline, responsible for transforming the raw output of the Liquid Argon (LAr) and Tile (TileCal) calorimeters into physics-ready cells. Due to its sequential nature, it may become a significant bottleneck. At the same time, Graphics Processing Units (GPUs) have become increasingly relevant in high-throughput scientific computing, offering massive parallelism and high-memory bandwidth. This dissertation investigates the feasibility of offloading the calorimeter bytestream decoding to GPUs and evaluates the performance of a prototype implementation integrated within the AthenaMT framework. A complete GPU-based pipeline was developed, including bytestream staging, device transfers, parallel fragment parsing and decoding for both LAr and TileCal. The implementation follows a modular CUDA C++ design tailored for parallel scalability. Validation against the CPU reference showed bit-identical agreement across all tested events. Performance measurements using Run-3 data demonstrated an order-of-magnitude improvement: while CPU decoding of a full calorimeter event takes on average 21.1 ms, the GPU prototype achieves 1.30 ms in synchronous and 1.08 ms in asynchronous mode on a constrained A100 MIG slice. These results confirm that massively parallel architectures can effectively accelerate calorimeter data preparation and motivate future accelerator-aware redesigns of the bytestream format for the HL-LHC.
- Accessible power for medical equipment in remote healthcare: a solution for single-phase power generation using three-phase induction machinesPublication . Romeiro, Bruno; Oliveira, Carlos; Hildenberg, Cicero; Ferreira, Ângela P.; Filho, FranciscoThis work was motivated by the urgent need for reliable electricity in remote areas where conventional power distribution, and consequently access to healthcare, remains impractical. The proposed system is a practical alternative to conventional synchronous generators commonly used in off-grid applications, which have high implementation and maintenance costs and potential risks in healthcare applications due to the spark generated by the brushes. We propose the use of a self-excited single-phase generator, derived from a three-phase induction machine, as a robust, low-cost, highly reliable and safe solution for supplying electrical power to medical applications in remote locations. The work presents a mathematical model based on the theory of symmetrical components, which incorporates frequency variation and unbalanced system operation, along with an analytical methodology to determine the capacitance values required for this application and all system elements, including the definition of the sizing factors KE and KM. The proposed approach allows for rigorous design without relying on empirical procedures as commonly presented in the literature, and is experimentally validated using real medical loads. Our experimental setup incorporates current medical devices, including three infusion pumps, a cardioverter-defibrillator, and a patient monitoring device. Despite modest voltage imbalances observed during steady-state operation, all medical devices maintained adequate functionality during testing. The transient response during load switching showed damped oscillations before returning to steady-state operation, demonstrating stable voltage and frequency behavior without the use of active electronic control. The generator demonstrated satisfactory voltage regulation and short-circuit self-protection capabilities without the need for complex systems, making it economically viable for deployment in resource-constrained environments. These results suggest that the proposed configuration offers a practical solution for the electrification of medical facilities in regions where grid extension remains challenging or prohibitively expensive.
- Accurate 3D numerical models for the fire performance on lsf partition walls under different fire scenariosPublication . Piloto, Paulo A.G.; Silva, Renata; Frizzera, Giovanna; Torres, Leonardo; Couto, Carlos; Vila Real, Paulo; Mesquita, Luís M.R.; Lopes, NunoThis study presents the development and validation of advanced 3D numerical models to analyse the fire performance of non-load-bearing Light Steel Frame (LSF) partition walls under different fire scenarios, specifically the standard ISO 834 and HYDROCARBON fire. Medium-scale experimental fire resistance tests from prior research were used for validation, focusing on LSF walls with and without cavity insulation (external composite insulation). Three computational solution methods were compared and used to predict the fire behaviour of LSF walls with a void cavity. The finite element method was employed for transient thermal analysis with temperature-dependent material properties, including adaptations to simulate material degradation such as gypsum board cracking and rock wool melting under HYDROCARBON fire conditions. Hydrocarbon fires reduced fire resistance by an average of 57% compared to ISO 834 fires for cavity-insulated walls, whereas external insulation configurations showed less reduction.