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Percorrer Faculdade Engenharia por Objetivos de Desenvolvimento Sustentável (ODS) "09:Indústria, Inovação e Infraestruturas"
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- Assessment of Airport Pavement Condition Index (PCI) Using Machine LearningPublication . Santos, Bertha; Studart, André; Almeida, Pedro G.Pavement condition assessment is a fundamental aspect of airport pavement management systems (APMS) for ensuring safe and efficient airport operations. However, conventional methods, which rely on extensive on-site inspections and complex calculations, are often time-consuming and resource-intensive. In response, Industry 4.0 has introduced machine learning (ML) as a powerful tool to streamline these processes. This study explores five ML algorithms (Linear Regression (LR), Decision Tree (DT), Random Forest (RF), Artificial Neural Network (ANN), and Support Vector Machine (SVM)) for predicting the Pavement Condition Index (PCI). Using basic alphanumeric distress data from three international airports, this study predicts both numerical PCI values (on a 0–100 scale) and categorical PCI values (3 and 7 condition classes). To address data imbalance, random oversampling (SMOTE—Synthetic Minority Oversampling Technique) and undersampling (RUS) were used. This study fills a critical knowledge gap by identifying the most effective algorithms for both numerical and categorical PCI determination, with a particular focus on validating class-based predictions using relatively small data samples. The results demonstrate that ML algorithms, particularly Random Forest, are highly effective at predicting both the numerical and the three-class PCI for the original database. However, accurate prediction of the seven-class PCI required the application of oversampling techniques, indicating that a larger, more balanced database is necessary for this detailed classification. Using 10-fold cross-validation, the successful models achieved excellent performance, yielding Kappa statistics between 0.88 and 0.93, an error rate of less than 7.17%, and an area under the ROC curve greater than 0.93. The approach not only significantly reduces the complexity and time required for PCI calculation, but it also makes the technology accessible, enabling resource-limited airports and smaller management entities to adopt advanced pavement management practices.
- Automated and Intelligent Inspection of Airport Pavements: A Systematic Review of Methods, Accuracy and Validation ChallengesPublication . Feitosa, Ianca; Santos, Bertha; Almeida, Pedro G.; mdpiAirport pavement condition assessment plays a critical role in ensuring operational safety, surface functionality, and long-term infrastructure sustainability. Traditional visual inspection methods, although widely used, are increasingly challenged by limitations in accuracy, subjectivity, and scalability. In response, the field has seen a growing adoption of automated and intelligent inspection technologies, incorporating tools such as unmanned aerial vehicles (UAVs), Laser Crack Measurement Systems (LCMS), and machine learning algorithms. This systematic review aims to identify, categorize, and analyze the main technological approaches applied to functional pavement inspections, with a particular focus on surface distress detection. The study examines data collection techniques, processing methods, and validation procedures used in assessing both flexible and rigid airport pavements. Special emphasis is placed on the precision, applicability, and robustness of automated systems in comparison to traditional approaches. The reviewed literature reveals a consistent trend toward greater accuracy and efficiency in systems that integrate deep learning, photogrammetry, and predictive modeling. However, the absence of standardized validation protocols and statistically robust datasets continues to hinder comparability and broader implementation. By mapping existing technologies, identifying methodological gaps, and proposing strategic research directions, this review provides a comprehensive foundation for the development of scalable, data-driven airport pavement management systems.
- Desenvolvimento de um novo material de embalagem alimentar: laminados de filme de proteína de soro do leite e papelPublication . Vaz, Rui Jorge Lopes; Ferreira, Ester Fernanda; Luís, Ângelo Filipe SantosOs plásticos estão presentes na sociedade sob a forma de diversos objetos indispensáveis à rotina humana. No entanto, estes materiais têm vindo a causar inúmeras consequências negativas para o meio ambiente e para a saúde pública. A problemática associada a este tipo de resíduo consiste no facto de não serem biodegradáveis, apresentarem um elevado nível de toxicidade e atuarem como vetores de diversos compostos químicos nocivos e microrganismos patogénicos. É relevante destacar que uma parte significativa dos resíduos plásticos encontrados no meio ambiente são provenientes da indústria de embalagens alimentares. Neste contexto, tem-se investigado intensamente acerca da substituição de polímeros provenientes de combustíveis fósseis por biopolímeros, os quais incluem polissacáridos, proteínas e lípidos. Nesta lógica, o presente trabalho teve como objetivo desenvolver um novo material de embalagem a partir de laminados constituídos por filme à base de proteína de soro do leite e papel, apresentando uma alternativa viável para a utilização das proteínas de soro do leite que são descartadas pela indústria de lacticínios. Os filmes foram produzidos através do método de evaporação de solvente, enquanto os laminados foram obtidos por calandragem, envolvendo processos mecânicos e químicos. As amostras foram caracterizadas por microscopia eletrónica de varrimento (SEM), calorimetria diferencial de varrimento (DSC) e espectroscopia de infravermelho por transformada de Fourier (FTIR). Adicionalmente, foram avaliadas as propriedades antioxidantes dos materiais através do ensaio de branqueamento do β-caroteno. Os laminados demonstraram propriedades mecânicas superiores em comparação com o filme isolado, bem como elevada atividade antioxidante. Verificou-se ainda que os polímeros apresentaram degradação térmica na faixa dos 250 °C. O protótipo de embalagem desenvolvido revelou-se termoselável e com elevado potencial na prevenção da peroxidação lipídica de nozes. Concluiu-se que o protótipo de embalagem desenvolvido a partir de polímeros biodegradáveis, representa uma alternativa promissora à substituição do plástico convencional, com propriedades funcionais adequadas para a conservação, em especial, de alimentos secos e com elevado teor lipídico.
- Driving Healthcare Monitoring with IoT and Wearable Devices: A Systematic ReviewPublication . João Pedro da Silva Baiense; Zdravevski, Eftim; Coelho, Paulo Jorge Simões; Serrano Pires, Ivan Miguel; Velez, Fernando J.Wearable technologies have become a significant part of the healthcare industry, collecting personal health data and extracting valuable information for real-time assistance. This review article analyzes 35 scientific publications on driving healthcare monitoring with IoT and wearable device applications. These articles were considered in a quantitative and qualitative analysis using the Natural Language Processing framework and the PRISMA methodology to filter the search results. The selected articles were published between January 2010 and May 2024 in one of the following scientific databases: IEEE Xplore, Springer, ScienceDirect (i.e., El- sevier), Association for Computing Machinery (ACM), Multidisciplinary Digital Publishing Institute (MDPI), or PubMed Central. The analysis considers population, methods, hardware, features, and communications. The research highlights that data collected from one or numerous sensors is processed and accessible in a database server for various uses, such as informing professional careers or assisting users. The review sug- gests that robust and efficient driving healthcare monitoring with IoT and wearable devices applications can be designed considering the valuable principles presented in this review.
- Dual-Purpose Star Tracker and Space Debris Detector: Miniature Instrument for Small SatellitesPublication . Beltran Nadal Arribas; Maia, João G.; Castanheira, João Pedro Conceição ; Filho, Joel Alves Costa ; Melício, Rui; Gordo, Paulo Romeu Seabra; Onderwater, Hugo; Duarte, Rui; Silva, André Resende Rodrigues daThis paper presents the conception, design and real miniature instrument implementation of a dual-purpose sensor for small satellites that can act as a star tracker and space debris detector. In the previous research work, the authors conceived, designed and implemented a breadboard consisting of a computer laptop, a camera interface and camera controller, an image sensor, an optics system, a temperature sensor and a temperature controller. It showed that the instrument was feasible. In this paper, a new real star tracker miniature instrument is designed, physically realized and tested. The implementation follows a New Space approach; it is made with Commercial Off-the-Shelf (COTS) components with space heritage. The instrument’s development, implementation and testing are presented.
- Fractal Patch Antenna based on Photonic Crystal for Enhanced Millimeter-Wave Communication in Intelligent Transportation SystemsPublication . Bagheri, Nila; Peha, Jon; Velez, Fernando J.; VelezThis paper introduces a Fractal Patch Antenna (FPA) integrated with Photonic Crystals (PhC) designed for Intelligent Transportation Systems (ITS) in the Millimeter-wave bands (mmWaves) given the importance of the application of mmWaves in Vehicle-to-Everything (V2X) networks, we assumed, as examples, that the antenna is designed to resonate at three frequency bands: 31.42 GHz, 37.76 GHz, and 38.92 GHz. With a gain of 10.88 dBi, at 38.92GHz, the antenna demonstrates promising signal reception and transmission capabilities, which are anticipated to be important for ITS operations. The antenna bandwidth covers multiple frequency bands, enabling versatile communication in mmWaves V2X applications. To evaluate the performance of the antenna, we conducted a detailed analysis of its configuration. This included a comparison of the antenna with and without the PhC integration, as well as an exploration of rectangular lattice structure. In addition, variations in hole sizes and spacing were examined to assess their impact on key parameters such as the gain and reflection coefficient. The integration of fractal geometry and PhC structures results in a compact, high-performance antenna suitable for mmWave communication. The integration of fractal geometry and PhC structure results in compactness and high performance in mmWaves communication applications. Through simulation and analysis, including radiation pattern, gain, and reflection coefficient plot assessment, the antenna performance is thoroughly evaluated. The study highlights the potential of the proposed FPA-PhC antenna configuration to enhance communication networks within the ITS, significantly advancing the ITS system with support from the mmWave bands.
- How different are conventional and biofuel sprays applied to aviation? An infodynamic comparative analysisPublication . Ferrão, Inês Alexandra dos Santos ; Panão, Miguel Rosa Oliveira; Mendes, Miguel; Moita, Ana Sofia Oliveira Henriques; Silva, André Resende Rodrigues daThe transition from fossil to sustainable and alternative fuels is imperative to address environmental concerns and meet energy requirements. Thus, the implementation of alternative fuels requires a deeper investigation of spray behavior. This study explores conventional jet fuel (Jet A-1) and hydrotreated vegetable oil (HVO) in terms of breakup length and spray dynamics over a wide range of operating conditions. The normalized mean breakup length was measured, and an empirical correlation was developed based on the experimental data. Focusing on the droplet sizes in fuel sprays, which are critical for optimizing combustion, an informational perspective for comparative analysis was explored. The terms informature, infotropy, and infosensor were introduced to quantify and capture the non-deterministic nature of physical systems. The results revealed similar drop size distributions for HVO and Jet A-1, with the Gamma function effectively characterizing the distributions. Both fuels exhibit spray evolution toward higher complexity states, emphasizing the role of aerodynamic forces and minimum development distance in atomization. The new lexicon of infodynamics views sprays as networks of information flow, with infotropy indicating that both fuels produce sprays with similar degrees of transformation. HVO is endorsed as a viable alternative with broader implications for sustainable aviation solutions and understanding complex engineering processes.
- Implementação de Workshops SMED: Uma abordagem estratégica no setor automóvelPublication . Sousa, Sofia Santos; Gaspar, Pedro Miguel de Figueiredo Dinis Oliveira; Silva, Miguel Moura daO forte desenvolvimento tecnológico e a evolução do mercado de trabalho têm impulsionado as organizações a procurar aumentar a sua eficiência operacional e, consequentemente a melhoria do seu desempenho. Para responder a estas exigências, surgiu a Filosofia Lean. Esta assenta num conjunto alargado de ferramentas e metodologias que visam eliminar os desperdícios e criar valor em qualquer tipo de processo produtivo. De entre as principais ferramentas Lean destaca-se o Single Minute Exchange of Die (SMED), uma metodologia amplamente utilizada na indústria automóvel que tem como principal objetivo a redução dos tempos de setup de uma máquina ou equipamento. O objetivo principal deste relatório de estágio assenta no planeamento e implementação de Workshops SMED para análise e otimização dos tempos de setup, das linhas de injeção no processo produtivo da empresa Aspöck Portugal S.A.. Para concretizar estes objetivos, foi selecionada uma linha de injeção, a PT_ IN019_INJ 110B, onde foi realizado o workshop, dividido em três fases, com a participação de um grupo multidisciplinar, promovendo um ambiente colaborativo. Os resultados obtidos após a 1ª e 2ª fases do workshop foram de uma redução do tempo de setup de 48:30 min:seg para 29:41 min:seg, totalizando um ganho de 38,8%. Este valor traduz o empenho e comunicação envolvido entre a equipa participante, traduzindo-se em ganhos significativos de produtividade e eficiência operacional. Na 3ª fase foi definida a sequência de trabalho padrão e elaborado o plano de ações corretivas e preventivas a curto e médio prazo. Foram identificadas 23 melhorias que visam otimizar o processo de mudança de referência. Destacam-se duas ações já concluídas e validadas, referentes à formação e acompanhamento das mudanças de setup para o 1º turno de trabalho. Estas ações resultaram no acompanhamento e validação de 13 mudanças de setup, pela equipa responsável, em diferentes máquinas, incluindo a máquina selecionada para o workshop. Verificaram-se resultados positivos, com reduções significativas nos tempos de setup, nomeadamente na máquina PT_ IN019_INJ 110B, com uma melhoria de 39,24%. Estes resultados comprovam a eficácia da abordagem adotada, possibilitando o cumprimento com as novas etapas estabelecidas, nomeadamente as formações programadas e os testes de soluções futuras para o 2º e 3º turnos de trabalho.
- Lean Management e o seu impacte operacional e financeiro na empresa CatraportPublication . Sobral, Gonçalo José Fonseca; Morais, Flávio Daniel Correia; Lima, Tânia Daniela Felgueiras de Miranda; Teixeira, João Manuel Carvalho SobrinhoEste trabalho explora a relevância do pensamento Lean na gestão empresarial de uma fábrica da indústria automóvel e metalomecânica enfatizando a adaptação às procuras do cliente. Assim, ao longo do documento destaca-se a necessidade imperativa da empresa Catraport reduzir os seus custos, otimizar os seus processos e aumentar a sua produtividade. Neste sentido, a dissertação ressalta a importância da implementação Lean, considerando-a uma metodologia valiosa na identificação de lacunas e orientação de transformações a serem executadas. O relatório de estágio focou na implementação das ferramentas Lean: SMED, 5S, Trabalho Padronizado e Gestão Visual numa das prensas do chão de fábrica com o principal objetivo de reduzir o tempo de troca de ordem de produção e aumentar a sua taxa de produção. Posteriormente, está retratada a analise do impacte financeiro resultante da variação do desempenho da eficiência operacional. Em síntese, a gestão Lean implementada neste relatório surge como um elemento crucial na busca contemporânea por eficiência, na melhoria contínua, no aumento do know-how de todos os trabalhadores. Esta apresenta-se como uma estratégia eficaz na otimização de atividades executadas na máquina em estudo, na redução de desperdícios Lean como tempo de espera e deslocações desnecessárias e melhoria da eficiência financeira na fábrica.
- Mitigating Dynamic Stall with a Movable Leading-Edge: the NACA0012-IK30 WingPublication . Camacho, Emanuel António Rodrigues ; Silva, André Resende Rodrigues da ; Marques, Flávio D.One major problem that affects rotor blade aerodynamics is dynamic stall, characterized by a series of events where transient vortex shedding negatively affects drag and lift, leading to abrupt changes in the wing’s pitching moment. The present work focuses on the mitigation of such effects by using a modified NACA0012 airfoil: the NACA0012-IK30 airfoil, used previously for thrust enhancement in flapping propulsion. An experimental rig is designed and built to study the advantages of a time-varying pitching leading edge on a plunging wing, more specifically its influence on the aerodynamic coefficients over time. Results indicate that when the wing is not experiencing significant stall, the movable leading edge does not hold considerable influence on drag or lift. However, it can reduce the pitching moment intensity by indirectly shifting the pressure center. Contrarily, when the wing is under proper dynamic stall, the movable leading edge truly improves the aerodynamic characteristics while operating at smaller effective angles of attack. This study contributes to the long-standing discussion on how to mitigate the adverse effects of dynamic stall by providing an innovative yet simple solution.
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