REPOSITÓRIO P.PORTO
Scientific Repository of the Porto Polytechnic
The Scientific Repository of the Polytechnic Institute of Porto's main goal is to provide all the scientific production of teachers, researchers and students of the Polytechnic Institute of Porto when possible in full text.The mission of the Scientific Repository of the Polytechnic Institute of Porto comprises up between two factors of extreme importance, the availability of scientific information and the preservation of digital information."Key Market": to make available in free access all the scientific production of the Polytechnic Institute of Porto."Contribution": aid students, researchers, teachers and the general public in obtaining reliable scientific production."Distinction": commitment that each user meets their scientific needs.
Recent Submissions
Product optimization using decision support tools
Publication . RAMALHO, RITA MOREIRA; Campilho, Raul Duarte Salgueiral Gomes; Barbosa, Flávia Vieira
The transition to a circular economy is currently a strategic priority in various industrial sectors, with the aim of increasing resource efficiency, reducing environmental impact, and extending product life cycles. However, the practical application of circularity principles to the redesign of existing industrial equipment remains a significant challenge. A review of the state of the art revealed an important gap: the lack of structured and integrative frameworks that guide product development and optimization, reconciling environmental, functional, and economic criteria. In this context, this work aims to develop and apply a circularity framework to support the redesign process of existing industrial equipment, specifically a stone cutting machine. The proposed framework is based on Lean Design-for-X principles and consolidated product engineering practices, combining digital tools, namely Solidworks and its simulation and sustainability modules, technical approaches gathered from the literature, and quantitative criteria for assessing structural, environmental, and economic performance. The methodology adopted followed an iterative approach, based on computer-aided engineering analyses and
finite element simulations, applied to the redesign of two critical structural components, the vertical supports and longitudinal beam. Several geometric and material alternatives were studied and designed aiming to improve stress distribution, reduce total mass, lower manufacturing costs, and minimize the environmental footprint, while ensuring that the company's functional requirements were met, namely structural integrity, displacement limits, and production feasibility. The results obtained demonstrated that the application of the
framework allowed balanced solutions to be achieved, integrating structural performance, sustainability, and comparative analysis of material costs. The final selection of configurations resulted directly from the framework-guided process, which provided clear criteria for evaluating the different alternatives in relation to the project objectives. Both the longitudinal beam and the vertical supports were optimized to ensure structural robustness and production efficiency, exploring more sustainable material options and proposals to improve the energy
efficiency of the equipment, while remaining within the functionality and manufacturing parameters stipulated by the company. This research thus validated the practical applicability of the proposed framework and confirmed its usefulness as a tool to support the development of more circular and sustainable solutions, also contributing to increasing the competitiveness of products in the market by assisting, from the design and conception phase, in the creation of efficient solutions aligned with current environmental and economic requirements. In practical terms, the requirements initially defined by the company were met, including aspects
related to structural performance, reduction of environmental impacts, and cost containment. In addition, the framework has broad potential for application to other types of equipment and industrial sectors, enabling companies to implement circular economy strategies from the early stages of design and redesign.
Development of microservices-based APIs for smart energy systems
Publication . COSTA, RODRIGO OLIVEIRA; Ramos, Sérgio Filipe Carvalho; Soares, João André Pinto
The transition to sustainable energy systems requires the seamless integration of diverse and distributed technologies. However, challenges related to standardization and interoperability across international platforms continue to hinder this progress. This thesis explores the development of a microservices-ready API tailored for Smart Energy Systems, addressing these integration barriers through a modular and scalable backend design. While a fully distributed microservices architecture was initially envisioned, the implemented solution adopts a
monolithic architecture structured according to microservices principles, enabling future service decomposition without significant redesign. The developed API aims to empower citizens to actively participate as prosumers within Energy Communities, supporting functionalities such as peer-to-peer energy trading, load management, and energy storage optimization. Designed with interoperability in mind, the platform promotes collaboration with international partners and facilitates integration into broader smart energy ecosystems. This work includes a comprehensive analysis of requirements, system architecture, implementation, and validation in realistic use cases. By aligning architectural flexibility with future scalability goals, the research contributes to the
advancement of citizen-centric and sustainable energy systems.
Eficiência operacional de detonadores eletrónicos versus não elétricos no desmonte de rocha
Publication . GOMES, RODRIGO RIBEIRO DA CUNHA; Fernandes, José Augusto Abreu Peixoto
A exploração de recursos minerais é uma atividade fundamental para o desenvolvimento das sociedades. A presente dissertação tem como principal objetivo investigar a influência da utilização de detonadores eletrónicos, em substituição dos detonadores não elétricos convencionais, na otimização do desmonte de rocha com explosivos. A revisão da literatura aborda os conhecimentos teóricos para a compreensão do trabalho, incluindo a caracterização geológico-geotécnica de maciços rochosos, a teoria do desmonte com explosivos e a cartografia geotécnica da pedreira do Facho, objeto de um estudo prévio. A metodologia experimental baseou-se na recolha e análise de dados de campo dos desmontes. As técnicas utilizadas incluíram a técnica da amostragem linear,
ensaios esclerométricos e a aplicação de softwares especializados, como o WipFrag. A análise dos dados inerentes ao plano de fogo, das curvas granulométricas obtidas com o WipFrag e das vibrações registadas com um sismógrafo permitiu comparar a qualidade dos desmontes que utilizaram detonadores não elétricos com os que recorreram a detonadores eletrónicos, identificando a influência da tecnologia eletrónica. Os resultados demonstram que a utilização de detonadores eletrónicos impacta positivamente na eficiência e qualidade do desmonte de rocha, confirmando as previsões da bibliografia.
Tradeoffs entre desempenho e energia em aplicações Java entre bases de dados relacionais e não relacionais
Publication . SOUSA, ROGÉRIO MOURA DE; Azevedo, Isabel de Fátima Silva
This dissertation investigates the performance and energy consumption tradeoffs in Java applications using relational and non-relational database technologies. With the increasing complexity and volume of data, the selection of an appropriate database system has become a critical decision for developers and system architects. Traditional relational databases such as PostgreSQL are known for their reliability and efficiency in structured data and complex queries, while non-relational databases like MongoDB and Apache Cassandra provide greater flexibility and scalability for handling unstructured or large datasets. The study adopts a rigorous methodology combining a literature review and controlled experiments to analyse three core aspects: the impact of the database type on performance and energy consumption in different database operations, the benefits of query optimisation techniques such as indexing, and the role of data volume in system efficiency. Multiple test
scenarios were designed and executed using tools such as Grafana k6 and Kepler to measure relevant performance and energy metrics. The results confirm that no single solution fits all cases. While relational databases perform better in consistency-heavy select operations and structured query workloads, non-relational
systems offer superior scalability and responsiveness in high-throughput or large-scale data environments. Additionally, the use of optimisation strategies was shown to significantly improve both energy efficiency and performance across database types. These findings highlight the importance of aligning database technologies with application-specific requirements to achieve energy-aware and performance-optimised solutions.
Technological interventions in mental health: A VR and mobile-based gamification approach for anxiety management
Publication . MASCARENHAS, RICARDO OLIVEIRA; Carvalho, Carlos Miguel Miranda Vaz de
Anxiety and panic attacks are among the most prevalent mental health challenges today, significantly impacting individuals’ daily lives, emotional stability, and overall well-being. Despite the availability of effective therapeutic techniques, such as guided meditation and breathing exercises, many individuals struggle to access and apply these tools consistently, particularly during acute episodes. This gap reveals the need for accessible, personalized, and engaging digital interventions that support both prevention and crisis management. This thesis presents the design, development, and evaluation of a digital solution that leverages Virtual Reality (VR) and mobile applications to assist individuals in managing anxiety. The system integrates evidence-based techniques into two primary modules: a Daily Work Module, promoting regular emotional regulation, and an SOS Module, for immediate intervention during crises. To maximize user engagement, the solution incorporates gamification elements grounded in psychological principles. Specifically, it maps the 5-4-3-2-1 grounding technique to a
sequence of interactive, sensory-focused mini-games. The development follows a lifecyclebased Work Breakdown Structure (WBS) and a Design-Based Research (DBR) methodology. The prototype was evaluated with two major approaches, involving usability testing (SUS) and qualitative feedback from both mental health experts and end-users. The results confirmed the high usability and therapeutic potential of the application. Participants reported
significant feelings of calmness and immersion, highlighting the effectiveness of the breathing and interactive grounding phases. The SOS mode was consistently validated as a valuable and reassuring feature for crisis management. Ethical considerations, such as data privacy and informed consent under GDPR, were paramount throughout the design. The outcome is a validated, user-centered framework for a gamified mental health tool
that combines therapeutic efficacy with technological innovation, demonstrating a promising direction for accessible and engaging digital interventions.