Publications Repository of the Polytechnic Institute of Bragança
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A Comprehensive Review of Fused Filament Fabrication: Numerical Modeling Approaches and Emerging Trends
Get PDFFused Filament Fabrication (FFF) has become a widely adopted additive manufacturing technology due to its cost-effectiveness, material versatility, and accessibility. However, optimizing process parameters, predicting material behavior, and ensuring structural reliability remain major challenges. This review analyzes state-of-the-art computational methods used in FFF, which are categorized into four main areas: melt flow dynamics, cooling and solidification, thermal-mechanical behavior, and material property characterization. Notably, the integration of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) has led to improved predictions of key phenomena, such as filament deformation, residual stresses, and temperature gradients. The growing use of fiber-reinforced filaments has further enhanced mechanical performance; however, this also introduces added complexity due to filler orientation effects and interlayer adhesion issues. A critical limitation across existing studies is the lack of standardized experimental validation methods, which hinders model comparability and reproducibility. This review highlights the need for unified testing protocols, more accurate multi-physics simulations, and the integration of AI-based process monitoring to bridge the gap between numerical predictions and real-world performance. Addressing these gaps will be essential to advancing FFF as a precise and scalable manufacturing platform.The authors acknowledge the project “0049_NATUR_FAB_2_E-Fomento de la especialización inteligente, transición industrial y emprendimiento a través de nuevos materiales basados em recursos endógenos compatibles com tecnologias de fabricación aditiva de gran formato” for the financial support, through the Programme Interreg VI A España–Portugal (POCTEP)
Creating resilient silvopastoral systems: Mediterranean silvopastoralism as a model for agroforestry
No full textO capítulo analisa os sistemas silvopastoris na Península Ibérica como um modelo de agrofloresta resiliente que integra árvores (sobretudo carvalhos), estrato arbustivo/herbáceo e gado. Enquadra a importância histórica de sistemas como o montado (Portugal) e a dehesa (Espanha), hoje pressionados pela intensificação agrícola, pelas políticas agrárias e pelas alterações climáticas, mas ainda relevantes pelo seu valor económico, ecológico e cultural. Descreve as interações entre ungulados domésticos e selvagens e os ecossistemas florestais: alimentação seletiva, pisoteio, deposição de estrume/urina e descasque, com efeitos na dispersão de sementes, composição da vegetação e propriedades do solo. Sublinha a “dupla face” destes efeitos: podem aumentar heterogeneidade, reciclagem de nutrientes e reduzir combustíveis finos, mas também provocar compactação, erosão, degradação do habitat e falhas de regeneração quando há sobrepastoreio e gestão inadequada. Aborda ainda como a cobertura arbórea condiciona o microclima, a água, luz e nutrientes, influenciando produtividade e qualidade da forragem, e como a sombra é crucial para o bem-estar animal em verões quentes, reduzindo o stress térmico. Por fim, destaca espécies e práticas-chave (Quercus ilex, Q. suber, Q. pyrenaica; ovinos, caprinos, bovinos e suínos em “montanera”) e defende a gestão integrada, inovação e coesão comunitária para assegurar a sustentabilidade futura e manter os serviços de ecossistema associados.The chapter analyses silvopastoral systems in the Iberian Peninsula as a resilient agroforestry model that integrates trees (especially oaks), a shrub/herbaceous layer, and livestock. It frames the historical importance of systems such as the montado (Portugal) and the dehesa (Spain), which are now under pressure from agricultural intensification, agricultural policies, and climate change, yet remain relevant due to their economic, ecological, and cultural value. It describes the interactions between domestic and wild ungulates and forest ecosystems—selective feeding, trampling, dung/urine deposition, and bark stripping—with effects on seed dispersal, vegetation composition, and soil properties. It highlights the “two-sided” nature of these effects: they can increase heterogeneity, nutrient cycling, and reduce fine fuels, but can also cause compaction, erosion, habitat degradation, and regeneration failure when overgrazing and inadequate management occur. It also discusses how tree cover shapes microclimate, water availability, light and nutrients, influencing forage productivity and quality, and how shade is crucial for animal welfare in hot summers by reducing heat stress. Finally, it highlights key species and practices (Quercus ilex, Q. suber, Q. pyrenaica; sheep, goats, cattle, and pigs in “montanera”) and argues for integrated management, innovation, and community cohesion to ensure future sustainability and maintain the associated ecosystem services
Dark tourism management and development: An exploratory analysis
No full textA review of recent relevant literature related to dark tourism from a management perspective indicates that there is an increasing academic interest in “dark tourism consumption,” “dark tourism motivation” and “dark tourism experience.” Thus, our goal is threefold: to delve into the research development on these three constructs, to critically analyze the current research, and bring to light research gaps and interrogations that deserve further consideration. This allows for detailed present implications besides indicating possible future developments that can or will impact dark tourism management and development. Due to the multidimensional nature of the approached constructs, we conducted an exploratory study because it gives researchers the ability to synthesize multiple points of view and harness unique erspectives while still allowing us to introduce rigor and objectivity into the analysis and discussion. This chapter contributes to a deeper understanding of dark tourism management and development by providing a novel conceptual framework. Nevertheless, some constraints exist when one seeks to carry out an exploratory study because when plunging into new realities, it is only possible to formulate hypotheses. The results, however, represent a theoretical advance for dark tourism studies and provide valuable insights into how it can be better managed and
developed
A Inteligência Artificial como Instrumento para a Inovação Pedagógica no Ensino Superior: Estudo de Caso em Cabo Verde
No full textEm Cabo Verde, a tecnologia digital tem vindo a assumir um papel cada vez mais relevante no domínio da educação. Nos últimos anos, foram desenvolvidas diversas iniciativas com o intuito de integrar as tecnologias digitais no currículo, contribuindo, assim, para o enriquecimento do processo de ensino-aprendizagem. Neste contexto, a presente investigação centra-se na seguinte questão: Que inovações pode a Inteligência Artificial (IA) introduzir no processo de ensino-aprendizagem no ensino superior em Cabo Verde? Para dar resposta a esta problemática, foram definidos os seguintes objetivos específicos: (i) analisar o potencial da IA na personalização do processo de ensino-aprendizagem; (ii) compreender o contributo da IA para a aquisição de conhecimentos pelos estudantes; (iii) identificar ferramentas de IA passíveis de serem utilizadas na dinamização do processo de ensino-aprendizagem; e (iv) explorar aplicações da IA no âmbito da avaliação e do feedback aos estudantes. A metodologia adotada seguiu uma abordagem mista, de natureza qualitativa e quantitativa, recorrendo-se, como instrumento de recolha de dados, ao inquérito por questionário. Os resultados obtidos permitem concluir que a integração da IA no ensino superior cabo-verdiano constitui ainda uma temática emergente. Verifica-se, contudo, um potencial significativo da IA na personalização do processo educativo, ajustando-o às necessidades individuais dos estudantes, reforçando a necessidade de aprofundar as investigações e de um maior compromisso institucional para promover uma implementação ética e eficaz dessas tecnologias no sistema de ensino superior de Cabo Verde, em particular, por parte das entidades governamentais com responsabilidade na tutela da Educação.In Cape Verde, digital technology is playing an increasingly important role in education. In recent years, various initiatives have been developed to integrate digital technologies into the curriculum, thereby enriching the teaching and learning process. In this context, this research centres on the following question: What innovations can Artificial Intelligence (AI) introduce into the teaching-learning process in higher education in Cape Verde? To answer this question, the following specific objectives were defined: (i) to analyse the potential of AI to personalise the teaching-learning process; (ii) to understand the contribution of AI to the acquisition of knowledge by students; (iii) to identify AI tools that can be used to boost the teaching-learning process; and (iv) to explore AI applications in the context of assessment and feedback to students. The methodology adopted followed a mixed qualitative and quantitative approach, using a questionnaire survey as the data collection tool. The results show that the integration of AI in Cape Verdean higher education is still an emerging issue. However, there is a significant potential for AI to personalise the educational process, adjusting it to the individual needs of students, reinforcing the need for further research and greater institutional commitment to promote the ethical and effective implementation of these technologies in Cape Verde's higher education system, particularly by government bodies responsible for education
A Computational Approach to Study Non-Synonymous Mutations
Get PDFNon-synonymous SNPs (Single Nucleotide Polymorphisms) result in amino acid substitutions within proteins. While some may have minimal impact on protein structure and function, others can significantly alter stability, conformation, and biological activity. Therefore, it is crucial to predict how SNP-induced changes affect protein structure and function. Here, we developed a novel pipeline that integrates bioinformatics and molecular modeling techniques to evaluate the structural and functional consequences of a non-synonymous SNP in a protein. Initially, Protein Plus was used to predict the potential active sites, which will help to determine whether a mutation is located within the functional binding regions. Identification of active sites is necessary to prioritize mutations that may alter protein structure and function. PolyPhen-2 and I-Mutant were used to evaluate the functional impact of mutations and the thermodynamic stability of the proteins. Next, to visualize the structural changes, AlphaFold3 was used to generate highconfidence 3D models for wild and mutant proteins. Finally, molecular dynamics (MD) simulations were conducted using YASARA to explore the dynamic behavior and stability of both mutant and wild-type proteins. MD simulations provide valuable insight into structural flexibility, potential conformational shifts, and the overall impact of the mutation on protein function. This computational pipeline provides a detailed framework to evaluate the structural and energetic consequences of non-synonymous mutations
Attention deficit hyperactivity disorder adhd drug use in the context of a sars cov 2 pandemic
Get PDFAttention Deficit Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood. Pharmacological treatment, primarily with methylphenidate, is widely used [2,3]. This study evaluates ADHD drug consumption patterns before and during the SARS-CoV-2 pandemic. Objectives: To analyse the consumption of ADHD medicines in community pharmacies in Bragança before and during the SARSCoV-2 pandemic. Methods: A retrospective, observational, and quantitative study was conducted using data from eight pharmacies between 2018 and 2021. Data were collected through Sifarma and 4DigitalCare software and analysed using SPSS and Excel. Results: Medicine consumption was higher in the pre-pandemic period (2018–2019, 50.97%) than during the pandemic (2020–2021, 49.19%). However, 2021 recorded the highest annual consumption (27%). Ritalin© LA 20mg was the most dispensed medicine. The autumn season showed the highest usage. There was variability in dispensing volumes between pharmacies. Conclusions: The pandemic led to a temporary reduction in ADHD medicine use. Nevertheless, the increased consumption in 2021 suggests a possible delayed pharmacological response due to prolonged confinement. These findings underscore the impact of public health crises on the management of chronic conditions and highlight the need for consistent support for individuals with neurodevelopmental disorders
AI shopping assistant
Get PDFThis project addresses the challenge of online shoppers feeling overwhelmed by the vast array of options available on e-commerce platforms, a problem that often leads to cart
abandonment and revenue losses for store owners. The proposed solution is the development of an AI-powered virtual fashion assistant capable of understanding customer
preferences in real-time and suggesting curated product recommendations. By offering personalized, streamlined guidance, the assistant simplifies the journey from browsing to
checkout while preserving the customer’s freedom to design a custom look. This approach not only enhances user satisfaction but also increases conversion rates and customer retention for online retailers
A portuguese case study on performance monitoring in technology transfer and valorisation centres using the balanced scorecard approach
Get PDFAligning strategic, operational, and technical priorities is critical for effective governance in Research and Development (R&D) organisations, especially those engaged in technology transfer and innovation. This article explores the development and application of the Balanced Scorecard (BSC) as a structured performance monitoring tool for a Portuguese Centre for the Valorisation and Transfer of Water Technology. Situated within the national network of technological interface centres, the research investigates how the BSC, supplemented by a strategic map, can support integrated management control by aligning organisational efforts with strategic goals. The study employs a qualitative case study methodology, with empirical data collected through three semi-structured interviews involving the centre’s CEO and two mid-level managers. The content analysis of interview transcripts enabled the identification of fourteen strategic objectives and their respective indicators, which were systematically mapped across the BSC’s four perspectives and interlinked through causal relationships. The results underscore the BSC’s potential to improve internal strategic coherence and monitoring capacity and to attend as a transferable framework for other public or private research centres facing similar challenges. The study offers both practical comprehensions for institutional management and conceptual contributions to the literature on performance management in the context of science, technology, and innovation
Analysis of DC-DC converters for integrated photovoltaic solar-powered electric bus charging systems
Get PDFThis article presents a theoretical study and validation of the feasibility of integrating photovoltaic (PV) systems to charge electric vehicles, with a focus on an electric bus as the model for analysis. The work further explores the design of an energy conversion system employing DC-DC converters, analyzing various converter types and configurations to maximize energy transfer efficiency. The study identifies optimal converter topologies and control strategies to enhance system performance.
Finally, the proposed models are validated through simulations in Matlab/Simulink, incorporating lithium-ion batteries as the energy storage system. The article aims to demonstrate how integrating photovoltaic energy into electric vehicle charging can serve as a sustainable and environmentally friendly solution, offering practical insights for improving energy efficiency in public transportation systems
Metagenomic analysis of the effects of plant- and yeast-based formulations on the grapevine leaf microbiome of cv. ‘Touriga Franca’
Get PDFGrapevine is highly susceptible to fungal diseases such as downy mildew and powdery mildew, which are traditionally managed through the intensive use of chemical fungicides. However, in the context of increasingly sustainable viticulture, biofungicides derived from plant and yeast extracts are gaining attention. Despite this, their impact on the grapevine leaf microbiome, crucial for plant health and disease resilience, remains underexplored. This study evaluated the effects of foliar applications of biofungicides (nettle extract, Japanese knotweed extract, and a yeast-based formulation - T66 and T90) in comparison with conventional chemical treatments and control (no treatment). Over two consecutive growing seasons, high-throughput sequencing was used to assess the diversity and composition of fungal and bacterial communities on grapevine leaves. Bacterial communities were more sensitive to treatments and interannual variability than fungal communities, which remained relatively stable. Conventional treatment (CT) showed the highest influence on fungal and bacterial composition, reducing the diversity of both. Some important fungal (Aureobasidium and Sporobolomyces) and bacterial (Pseudomonas and Sphingomonas) genera associated with the promotion of plant growth, health, and biocontrol were detected. These findings reinforce the potential of new treatments with putative fungicide effects to modulate the leaf microbiome, particularly bacterial communities, without disrupting the natural fungal balance. Thus highlight their relevance for developing sustainable viticultural practices aimed at improving plant protection.The author(s) declare financial support was received for the research and/or publication of this article. This research was funded by the European Regional Development Fund through the INTERREG Atlantic Area Program, under the NASPA-natural fungicides against air and soil borne pathogens in the Atlantic Area project (EAPA-451/2016) and by the National Funds by FCT -Portuguese Foundation for Science and Technology, under the projects UID/04033/2023: Centre for the Research and Technology of Agro-Environmental and Biological Sciences and LA/P/0126/2020 (https://doi.org/10.54499/LA/P/0126/2020)