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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.
- An integrated and interoperable AutomationML-based platform for the robotic process of metal additive manufacturingPublication . Babcinschi, Mihail; Freire, Bernardo; Ferreira, Lucía; Señaris, Baltasar; Vidal, Felix; Vaz, Paulo; Neto, PedroIncreasingly, industry is looking to better integrate their industrial processes and related data. Interoperability is key since the organizations need to share data between them, between departments and the different stages of a given technological process. The problem is that many times there are no standard data formats for data exchange between heterogeneous engineering tools. In this paper we present an integrated and interoperable AutomationML-based platform for the robotic process of metal additive manufacturing (MAM). Data such as the MAM robot targets and process parameters are shared and edited along the different sub-stages of the process, from Computer-Aided Design (CAD), to path planning, to multiphysics simulation, to robot simulation and production. The AutomationML neutral data format allows the implementation of optimization loops connecting different sub-stages, for example the multi-physics simulation and the path planning. A practical use case using the Direct Energy Deposition (DED) process is presented and discussed. Results demonstrated the effectiveness of the proposed AutomationML-based solution.
- Analysing the different interrelationships of soil organic carbon using machine learning approaches: Assessing the specific case of PortugalPublication . Pereira Domingues Martinho, Vítor João; Ramos, Tiago Brito; Castanheira, Nádia; Cunha, Carlos; Ferreira, António José Dinis; Pereira, José Luís da Silva; Sánchez-Carreira, Maria del CarmenGiven the importance of soil organic carbon (SOC) for sustainability, policymakers and researchers are particularly concerned with identifying the conditions that promote carbon storage in the soil. These assessments provide relevant support for the design of policy instruments aimed at increasing soil quality and its carbon sequestration capacity. The new technologies associated with the digital transition can bring relevant added value, namely through artificial intelligence methodologies, where machine learning approaches are important. In this context, this research aims to analyse the several interrelationships of SOC in the specific Portuguese context, with a focus on highlighting its main predictors and providing proposals for stakeholders (including policymakers). To achieve these objectives, statistics from the INFOSOLO database were considered and evaluated using machine learning algorithms to select the most important SOC predictors and identify accurate models. These interrelationships were quantified with cross sectional regressions and optimisation models. The results obtained provide relevant information for the design of adjusted policy measures that promote sustainable practices and increase soil quality. Generally, Portuguese soils have low organic carbon content due to soil features, climate circumstances and land management. Adjusted management of agroforestry activities is possibly the easiest part to deal with in this context.
- 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.
- Antioxidant and Antimicrobial Activity Characteristics of Seven Biopreparations Used in Organic FarmingPublication . Simões, Joana; Peleja, Ana; Neves, Cláudia; de Vasconcelos Teixeira Aguiar da Costa, Daniela; de Paiva Martins Esteves Correia, Helena Maria; Pinto, António; Ferreira Wessel, Dulcineia; Costa, Cristina Amaro da; Delgado, Fernanda; Carneiro, João Paulo; Horta, Carmo; Bahcevandziev, Kiril; Vidal, Maria; Filipe, OlgaAgroecological transition is a major societal challenge and it is urgent to support technical solutions to answer farmers demand towards the necessary changes. The project RESTORE - biopReparados Em SisTemas prOdução agRoEcológicos aimed to study and validate the production, conservation, and use of seven biopreparations by characterizing and testing them in lettuce nurseries. The biopreparations used include prickly pear vinegar, purslane vinegar, fermented orange juice, garlic extract, nettle infusion, horsetail decoction and a biopreparation of garlic and chilli. The in vitro microbiological characterization and chemical analysis of the biopreparations, which included phenolic composition and antioxidant capacity, allowed us to understand their properties and to propose the most appropriate conservation strategy. The tests were conducted in four different moments: during the biopreparations’ manufacturing, after six months of frozen storage, and after three and six months of fresh storage. One-Way ANOVA in SPSS 29.0 and PCA comparison tests were used to analyze the results. Fermented orange juice and vinegars were the biopreparations that showed the greatest outcomes in terms of antioxidant capacity and phenolic composition. Purslane vinegar had the highest average inhibition against germs. The concentration of phenolic compounds, the antioxidant capacity, and the antibacterial activity of the biopreparations varied with time and type of conservation. It is crucial to conduct more trials, using different species and recipes, to support farmers’ decision making and adoption of agroecological solutions.
- Aplicação da metodologia DMAIC em uma empresa produtora de componentes de borrachaPublication . Almeida, Ricardo; ANTUNES VAZ, PAULO JOAQUIM; Gomes da Silva, Rosa Maria; AlmeidaIntrodução: Nas últimas décadas, foram feitos grandes desenvolvimentos na indústria. As empresas aprimoraram-se para fazer o produto final com mais qualidade e com grande redução de custos. As metodologias Lean foram implementadas em todos os tipos de indústrias e negócios, rompendo com o tipo de produção que se praticava na época, que se baseava em grandes volumes e pouco flexíveis. As metodologias Lean começaram quando os funcionários e engenheiros da Toyota começaram a desenvolver procedimentos e ferramentas para permitir a produção lean, com desperdício zero e sistemas de produção altamente flexíveis. Objetivo:A reorganização do layout do departamento de manutenção, assim como, a melhoria do processo de gestão das spare partse a criação de fluxos para a reparação de equipamentos e ferramentas. Métodos: A ferramenta utilizada foi o DMAIC, esta subdivide o processo de resolução de problemas em cinco etapas, tais como: Definir, Medir, Analisar, Melhorar, Controlar. Resultados: Com a aplicação desta ferramenta foi possível uma redução do número de deslocações e da distância percorrida, (que por sua vez, permitiu também a diminuição do tempo necessário para a sua realização) deste modo o tempo necessário para a sua realização também diminuiu. As spare parts estão mais organizadas, cada bancada de trabalho possui as peças de substituição de maior consumo. A pontuação obtida nas auditorias 5’S também apresentaram um aumento face aos resultados obtidos antes da intervenção. Conclusão: Conclui-se que a causa raiz e as soluções definidas impactaram positivamente a eliminação da causa e problema iniciais.
- Aplicação do Lean Seis Sigma no Setor do Turismo: Um estudo de caso na Indústria Hoteleira PortuguesaPublication . ANTUNES VAZ, PAULO JOAQUIM; Rocha, Sílvia; Reis, Marco S.; Silva, Cristóvão; Vaz, MariaNum ambiente cada vez mais competitivo, fatores como a eficiência, a qualidade de produtos, processos e serviços, assim como a satisfação de clientes, são, cada vez mais determinantes para o sucesso de qualquer organização. Para atingir estas vantagens competitivas, iniciativas de Qualidade como o Lean e o Seis Sigma têm revelado ser importantes estratégias de negócio em muitas indústrias em todo o mundo. No entanto, apesar da sua aplicabilidade ser praticamente transversal a todos os setores da economia, estas metodologias ainda não despertaram, tanto quanto se sabe, um interesse generalizado no setor do Turismo em Portugal. No sentido de colmatar esta lacuna, este trabalho procura avaliar a oportunidade de implementar estas metodologias de qualidade no setor do Turismo, mais concretamente na Hotelaria Portuguesa. Foi feito um levantamento das práticas correntes de implementação de sistemas de qualidade na Hotelaria Portuguesa. Adicionalmente, foi ainda implementada a iniciativa Lean Seis Sigma a um estabelecimento Hoteleiro Nacional, recorrendo à metodologia do Seis Sigma para a resolução de problemas – DMAIC (Define, Measure, Analyse, Improve e Control), tendo sido realizadas as primeiras três etapas e elencadas propostas de melhorias a implementar na fase seguinte. Este trabalho permite analisar a pertinência da implementação do Lean Seis Sigma na Hotelaria Portuguesa, bem como avançar com a sua aplicação a um caso prático.
- 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
- Bio-Regions as An Innovative Model of Sustainable Rural Development: An Integrative Literature ReviewPublication . Lagoa, Rui; Florença, Sofia de Guiné e; Tibério, Manuel; Gonçalves, Ramiro; Costa, Cristina Amaro daThe Bio-Regions, whose origin dates back to Italy, constitute an innovative model of rural development anchored in endogenous dynamics, valuing territorial specificities, local social capital and participatory governance mechanisms. Its integrated approach seeks to articulate organic farming, environmental sustainability, community cohesion and proximity circuits. This study aims to contribute to the scientific and political debate around Bio-Regions, exploring their transformative potential in the context of territorial public policies. Through an integrative literature review, we sought to understand not only the conceptual and practical evolution of the Bio-Regions, but also the implications of their consolidation in different territorial contexts. The analysis focused on indexed scientific publications and non conventional specialized literature, collected through professional and academic networks. The selection of contributions was guided by thematic criteria, favoring studies that addressed institutional factors, the mobiliza tion of local actors and the role of public policies in the operationalization of this development model. The results highlight the decisive role of the institutional dimension in the consolidation of Bio-Regions, underlining the importance of integrated and participatory political strategies. At the same time, significant gaps in sci entific production are identified, particularly with regard to the systematic assessment of the economic, social and environmental impacts associated with the implementation of the Bio-Regions.
- Biopreparados agroecológicos como solução biológicaPublication . Simões, Joana; de Vasconcelos Teixeira Aguiar da Costa, Daniela; Costa, Cristina Amaro daNa sociedade atual, a sustentabilidade ambiental e social é uma preocupação crescente, em particular na produção de alimentos que se traduz na crescente procura por produtos seguros para os ecossistemas e para o consumidor final. A utilização de biopreparados, com base na (re)utilização de recursos naturais existentes na exploração, é uma parte integrante de sistemas produção agroecológicos. Estudaram se sete biopreparados agroecológicos no projeto RESTORE - biopReparados Em SisTemas prOdução agRoEcológicos [projeto UIDB/00681/2020] – vinagre de figo-da-índia, vinagre de beldroega, sumo fermentado de laranja, extrato de alho, infusão de urtiga, decocção de cavalinha e biopreparado de alho e malagueta. O trabalho consistiu em: aplicação de inquérito aos agricultores sobre biopreparados utilizados; seleção e produção, análise físico-química e microbiológica e avaliação de efeitos in vivo de biopreparados. Foram realizados 17 inquéritos a produtores, na região Centro. Os biopreparados foram selecionados a partir da informação dos agricultores. Em laboratório, procedeu-se à quantificação de compostos fenólicos totais, análise da capacidade antioxidante e a da inibição de atividade microbiana, em bactérias e fungos, em três momentos temporais diferentes e com base no tipo de conservação estabelecida: logo após a preparação do biopreparado; três e seis meses após a conservação em fresco e seis meses após conservação por congelação. Os ensaios de campo foram realizados em viveiros de alface, em estufa, desde a sementeira até à transplantação. O sumo fermentado de laranja e os vinagres apresentam os melhores resultados em composição fenólica e capacidade antioxidante. Em termos de inibição de atividade microbiológica, o biopreparado de alho e malagueta é o que demonstra uma inibição mais consistente. A decocção de cavalinha demonstra apresentar melhores resultados enquanto bioestimulante no cultivo de alface. É essencial dar continuidade a estudos de avaliação dos efeitos dos biopreparados para melhorar o conhecimento sobre os mesmos e os seus efeitos, bem como para fundamentar uma tomada de decisão mais adequada.