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- Adaptive and Scalable Database Management with Machine Learning Integration: A PostgreSQL Case StudyPublication . Abbasi, Maryam; Bernardo, Marco V.; Vaz, Paulo; Silva, José; Martins, Pedro; ANTUNES VAZ, PAULO JOAQUIM; Silva, JoséThe increasing complexity of managing modern database systems, particularly in terms of optimizing query performance for large datasets, presents significant challenges that traditional methods often fail to address. This paper proposes a comprehensive framework for integrating advanced machine learning (ML) models within the architecture of a database management system (DBMS), with a specific focus on PostgreSQL. Our approach leverages a combination of supervised and unsupervised learning techniques to predict query execution times, optimize performance, and dynamically manage workloads. Unlike existing solutions that address specific optimization tasks in isolation, our framework provides a unified platform that supports real-time model inference and automatic database configuration adjustments based on workload patterns. A key contribution of our work is the integration of ML capabilities directly into the DBMS engine, enabling seamless interaction between the ML models and the query optimization process. This integration allows for the automatic retraining of models and dynamic workload management, resulting in substantial improvements in both query response times and overall system throughput. Our evaluations using the Transaction Processing Performance Council Decision Support (TPC-DS) benchmark dataset at scale factors of 100 GB, 1 TB, and 10 TB demonstrate a reduction of up to 42% in query execution times and a 74% improvement in throughput compared with traditional approaches. Additionally, we address challenges such as potential conflicts in tuning recommendations and the performance overhead associated with ML integration, providing insights for future research directions. This study is motivated by the need for autonomous tuning mechanisms to manage large-scale, hetero geneous workloads while answering key research questions, such as the following: (1) How can machine learning models be integrated into a DBMS to improve query optimization and workload management? (2) What performance improvements can be achieved through dynamic configuration tuning based on real-time workload patterns? Our results suggest that the proposed framework significantly reduces the need for manual database administration while effectively adapting to evolving workloads, offering a robust solution for modern large-scale data environments.
- Analysis of Governance models for sustainable and healthy food systemsPublication . Florença, Sofia de Guiné e; Amaral, Ana Luísa; Costa, Filipa; Guiné, Raquel; Costa, Cristina Amaro daSustainable food systems are systems that safeguard economic, social and environmental sustainability by fomenting social progress, promoting efficient management of natural resources, providing nutritious food and ensuring fair compensation for all actors in the food chain. In recent years, several initiatives worldwide have been created to ensure and promote the sustainability of the current food systems. These initiatives aim to enable people to have access to quality, nutritious and sustainable foods, combat social and economic inequalities and promote synergies between consumers and producers. To promote these initiatives is crucial in order to contribute to improved food consumption and production patterns towards more nutritive and sustainable foods. The objective of this research was to identify and characterize sustainable food initiatives in order to understand their structure, model of governance, motivations, typology of actors involved and future prospects. This investigation was based on an interview guide that was applied to the managers or those responsible for the sustainable initiatives related with the food system. Seven initiatives were included, and the semi- structured interviews were carried out online during the summer of 2024. The recorded interviews were transcribed, and the content analysed. The results obtained by the interviews showed that the principal motivators are related to food and sustainability, in all three, economic, environmental and social, dimensions. It was further identified that the most important cause of success was the availability and commitment of the people involved in the initiative. The seven initiatives analysed were implemented to meet local needs, both of producers and consumers, while promoting sustainability. Furthermore, they aimed at encouraging economic circularity, transference and sharing of knowledge, valorisation of local and rural resources, and management of food waste. These aspects contribute to more efficient and eco-friendly local food supply chains, providing the consumers with fresher and heathier food products. The existence of local or nationwide initiatives related with the sustainability of food system contribute to a more efficient use of natural resources in order to obtain healthy, sustainable and fair food products, that the modern consumers tend to value in search for a more friendly co-existence between the necessity to produce food and the recognized need to preserve the natural ecosystems.
- Assessing Cultural Variations in Nutrition Environment Measures Survey in Stores (NEMS-S): A Global Perspective on Food Availability and QualityPublication . Florença, Sofia de Guiné e; Simões J; Amaro da Costa, Cristina Isabel; Cunha Silva Reis Lima, Maria Joao; Guiné, Raquel; Teixeira-Lemos, Edite
- Characterization of Sustainable Food Initiatives: Preliminary Study.Publication . Florença, Sofia de Guiné e; Amaral, Ana Luísa; Costa, Filipa; Guiné, Raquel; Amaro da Costa, Cristina IsabelAbstract: A sustainable food system can be described as a system that ensures economic, social, and environmental sustainability to secure food and nutrition for current and future generations. The present research aimed to identify and characterize sustainable food initiatives to understand the governance framework, the motivations, the reasons for success, the typology of actors involved, and future prospects. Semi-structured interviews were conducted for seven initiatives between June and August 2024. The interviews were performed online, recorded, transcribed, and analyzed. The results showed that the main drivers of the initiatives relate to food, sustainability, and economic and social dimensions. Moreover, one of the reasons for the success of the initiatives is the availability and commitment of the people involved. These initiatives were created to meet local needs and promote sustainability as well as to encourage economic circularity, knowledge sharing, rural and local valorization, and waste management.
- Comparison of milk consumption habits across two European countries: Pilot study in Portugal and FrancePublication . Guiné, Raquel P. F.; Florença, Sofia de Guiné e; Bréjon, M.; Gonçalves, João Carlos; Ferreira, Manuela; Barroca, Maria João; Fragata, AnabelaHumans have been consuming milk obtained from domesticated animals since ancient times. Milk is a very complete food with important nutrients that can sup- port life. However, the patterns of consumption of milk have been shifting. On one hand, due to the increase in the number of people with intolerances (to lactose, for example), and on the other hand, due to some trend to avoid foods from animal origin owing to speci fi c convic- tion (like animal welfare, for example). In this context, this study focused on the milk consumption patterns in two di ff erent European Countries and the evaluation of pos- sible di ff erences. The object of study was milk obtained from animal sources, namely, cows, and no other derived fermented dairy products were included. For the develop- ment of the study, a questionnaire survey was applied to a sample of 542 participants from both countries using the Internet. The results showed that a high percentage of participants in both countries consume milk regularly, and the usual amount varies between 125 and 250 mL per day. For those who do not consume milk, the most relevant reason pointed out in both countries was because they do not feel the need to consume it. While in France, a high percentage also do not consume because they do not like milk, and in Portugal, a high percentage do not consume milk due to lactose intolerance. The most con- sumed is semi-skimmed milk, and preferences are towards consuming plain milk or consuming it with chocolate. Signi fi cant di ff erences were found in the consumption of white brands, which are preferred in France, while in Portugal, consumers prefer commercial brands, as well as the preferred package, tetra packs for the Portuguese, while the French prefer plastic bottles. In conclusion, although the results showed some similar trends among the participants from both countries, some di ff erences were also identi fi ed that can be used to better plan public policies in both countries.
- Comprehensive Evaluation of Deepfake Detection Models: Accuracy, Generalization, and Resilience to Adversarial AttacksPublication . Abbasi, Maryam; ANTUNES VAZ, PAULO JOAQUIM; Silva, José; Martins, PedroThe rise of deepfakes—synthetic media generated using artificial intelli gence—threatens digital content authenticity, facilitating misinformation and manipu lation. However, deepfakes can also depict real or entirely fictitious individuals, leveraging state-of-the-art techniques such as generative adversarial networks (GANs) and emerging diffusion-based models. Existing detection methods face challenges with generalization across datasets and vulnerability to adversarial attacks. This study focuses on subsets of frames extracted from the DeepFake Detection Challenge (DFDC) and FaceForensics++ videos to evaluate three convolutional neural network architectures—XCeption, ResNet, and VGG16—for deepfake detection. Performance metrics include accuracy, precision, F1-score, AUC-ROC, and Matthews Correlation Coefficient (MCC), combined with an assessment of resilience to adversarial perturbations via the Fast Gradient Sign Method (FGSM). Among the tested models, XCeption achieves the highest accuracy (89.2% on DFDC), strong generalization, and real-time suitability, while VGG16 excels in precision and ResNet provides faster inference. However, all models exhibit reduced performance under adversarial conditions, underscoring the need for enhanced resilience. These find ings indicate that robust detection systems must consider advanced generative approaches, adversarial defenses, and cross-dataset adaptation to effectively counter evolving deep fake threats
- Contemporary challenges in foreign language learning in higher education: rethinking the interactions between digital tools, cultural intelligence and cognitive load for a balanced active pedagogyPublication . Delplancq, Véronique; Costa Lopes, Ana Maria; Pereira, José Manuel de Almeida; Gillain, Romain; Fidalgo, Susana; IJARThe use of digital tools in foreign language learning in higher education raises many pedagogical challenges, particularly in terms of the skills to be developed, vital for society and the labour world, while simultane ously managing the cognitive load of students. Based on the results of experiments carried out with undergraduate Media Studies students at the Escola Superior de Educação de Viseu(Portugal), the paper questions the effects of applying active pedagogies using digital tools upon the acquisition of these competences, with particular focus on cultural intelligence, while keeping students' cognitive load balanced. Results show that pedagogical activation can favour the development of diverse competences and cognitive processes, but presents risks, namely overload in the case of poorly planned activities. The article aims to contribute to the design of balanced, rich and cognitively sustainable pedagogical devices, contributing to an active pedagogy with the integration of the digital tools.
- Data Privacy and Ethical Considerations in Database ManagementPublication . Pina, Eduardo; Ramos, José; Jorge, Henrique; ANTUNES VAZ, PAULO JOAQUIM; Vaz, Paulo; Silva, José; Wanzeller, Cristina; Abbasi, Maryam; Martins, Pedro; Silva, José; Wanzeller Guedes de Lacerda, Ana CristinaData privacy and ethical considerations ensure the security of databases by respecting individual rights while upholding ethical considerations when collecting, managing, and using information. Nowadays, despite having regulations that help to protect citizens and organizations, we have been presented with thousands of instances of data breaches, unauthorized access, and misuse of data related to such individuals and organizations. In this paper, we propose ethical considerations and best practices associated with critical data and the role of the database administrator who helps protect data. First, we suggest best practices for database administrators regarding data minimization, anonymization, pseudonymization and encryption, access controls, data retention guidelines, and stakeholder communication. Then, we present a case study that illustrates the application of these ethical implementations and best practices in a real-world scenario, showing the approach in action and the benefits of privacy. Finally, the study highlights the importance of a comprehensive approach to deal with data protection challenges and provides valuable insights for future research and developments in this field
- Designing Inclusive Smartwatch Interfaces: Guidelines for Enhancing Usability and Adoption Among Older AdultsPublication . P. Duarte , Rui; Alves, Valter; Alves, Valter; Mota, MikaelAging introduces sensory, motor, and cognitive challenges and limited familiarity with digital interfaces, often hindering older adults’ adoption of new technologies. Smartwatches, with their compact size and health monitoring features, promise to improve older adults’ quality of life. However, their small screens and complex interfaces create significant usability barriers. While guidelines for mobile and web interfaces exist, frameworks for smartwatch design still need to be explored. This study addresses this gap by proposing smartwatch-specific design guidelines for older adults. Through an analysis of user challenges, existing design principles, and smartwatch constraints, the research formulates actionable recommendations to enhance usability and user experience. The contributions include identifying key obstacles older adults face with smartwatches, evaluating the applicability of established guidelines, creating tailored design principles for small screens, and developing a design system that balances simplicity, usability, and functionality. These contributions aim to facilitate smartwatch adoption and improve the inclusivity of digital technologies for older adults.
- Diálogos Ibéricos y Transatlánticos. Mapeando las redes intelectuales en torno al Hispanismo de António Sardinha. Transcripción y edición crítica y anotada del epistolario y textos dispersos (1906-1925)Publication . Rocha Relvas, SusanaEste volumen ofrece una lectura renovada del pensamiento hispánico de António Sardinha, figura central del Integralismo Lusitano, en diálogo con destacados actores culturales y políticos de España y América Latina. A partir de un extenso epistolario —en su mayoría inédito— y de textos dispersos que se presentan aquí en edición crítica y anotada, se reconstruye el entramado de contactos e influencias que Sardinha fue tejiendo a lo largo de su trayectoria intelectual con figuras clave del mundo ibérico e iberoamericano. Fruto de más de veinticinco años de investigación documental, este libro traza el mapa de un pensamiento que, en el centenario de la muerte de su autor, invita a repensar los vínculos históricos, espirituales y culturales que siguen articulando el imaginario ibérico e iberoamericano.