ESTiG - Artigos em Proceedings Não Indexados à WoS/Scopus
URI permanente para esta coleção:
Navegar
Entradas recentes
- Data acquisition system for a wearable-based fall preventionPublication . Kaizer, Raul; Sestrem, Leonardo; Franco, Tiago; Gonçalves, João; Teixeira, João Paulo; Lima, José; Carvalho, José Augusto; Leitão, PauloReliable ways to treat and monitor patients remotely have been researched and proposed by numerous people. Many of these propositions are under the wearable category due to it usually not requiring deep knowledge to be handled and its durability. Among the many applicable ways, fall monitoring has gained importance as the world population ages and countries aim to increase the quality of life. For it to be possible, there are many ways such as analyzing muscle response, body position, or brain activities, but for most of them, the result ends up being expensive and or inaccurate. With this in mind, this paper brings the development of an acquisition system for electromyography, electrocardiography, body position and temperature. The acquired data is transmitted to the smartphone through Bluetooth Low Energy (BLE) and then sent to a secure cloud to be provided to the physician. In future works, artificial intelligence codes will analyze the data patterns to predict fall occurrences and establish functional electrical stimulation (FES) routines to prevent falls and or treat the patients according to their necessities.
- Speaker recognitionin door access control systemPublication . Manfron, E.; Teixeira, João Paulo; Mineto, R.In this paper, we explore the potential of speaker recognition technology as a biometric authentication method for access control systems. We focus on the development and evaluation of two machine learning models, the Gaussian Mixture Model (GMM) and Multilayer Perceptron (MLP), for speaker identification. Our research presents a review of speaker recognition literature, followed by a detailed methodology for constructing and training the GMM and MLP models on a specific dataset. Experimental results highlight the performance of these models in terms of accuracy and efficiency. This study contributes to the application of GMM and MLP models for speaker recognition-based access control systems, serving as a resource for future research and development in secure and effective access control solutions.
- Mapping user needs in the competitive trading card game communityPublication . Puvaca, Bojan; Almeida, João P.; Duarte, António; Šebek, StjepanTrading card games (TCGs) have evolved from locally rooted communities to globally connected networks of players who rely on online platforms for strategy discussion. Despite the increasing availability of digital tools, most do not adequately address the specific and complex needs of competitive players. This paper explores how lightweight, qualitative methods can help uncover user expectations within this globally dispersed and specialized community. A survey was distributed across various online TCG communities, to collect information about their practices and feelings about existing tools. The data was analyzed using empathy mapping to highlight user perspectives, and affinity diagramming to group recurring needs, behaviors, and frustrations. These methods helped uncover gaps between what current tools offer and what players require. The findings are used for the development of a new platform that assesses the specific needs of competitive TCG players. Future work will include continuous user feedback monitoring and localization efforts to serve international audiences more effectively. This study provides a replicable approach for researchers and designers working with specialized global userbases where standard UX methods may fall short.
- QualyTools: an online collection of tools for quality management and controlPublication . Barreto, Paulo Gomm; Duarte, AntónioQuality practitioners use a varied set of tools to diagnose, stabilize, improve and control business processes and aid in decision making. Most of the tools are well known and several implementations exist across statistical software packages or other software, and online resources. While some tools are generic (e.g. a histogram) other tools are more specific to quality (e.g. a control chart), but they are often integrated into expensive software bundles that are of little use for quality practitioners. We developed an application (QualyTools) that integrates a set of essential tools for quality management and control. These tools cover common needs and include distribution analysis (histogram and scatter plots), Pareto charts, control charts, and capability analysis. The tools were implemented in an application developed using the R shiny package and framework. The collection was published online and can be freely used. We also kept the application code open to collaboration, by means of a GitHub repository. The primary objective of the application is to provide an integrated, efficient and accessible solution for statistical and visual analyses, allowing users to transform data into relevant information to support decision making. The tools can be a resource for practitioners and quality management students.
- Development of an integrated portal for farm audit management with geospatial supportPublication . Correia, Maria; Alves, Joaquim; Sequeira, Romeu; Exposto, JoséThis paper introduces the development of an innovative portal designed to optimize the management of agricultural field audits and ensure compliance with Common Agricultural Policy (CAP) regulations. The system is capable of handling more than five thousand audits, addressing specific audit requirements and integrating geospatial data management through technologies such as Django, and PostGIS, alongside libraries like Leaflet.js and Chart.js. The back end, developed in Django, provides a scalable and reliable infrastructure, supported by containerization deployment, while the front-end offers intuitive tools for data visualization and interaction. The platform’s modular design allows users at various access levels to efficiently manage data, track audit progress, upload documents, and monitor resources. By consolidating all audit tasks into a single application, the system reduces processing time, simplifies workflows, and improves data accuracy, leading to greater overall productivity. Preliminary testing demonstrates the system’s effectiveness for large-scale audits, and its scalability allows for future integrations, including IoT devices and predictive analytics, further enhancing decision-making and real-time data collection. This flexible and efficient solution meets the evolving needs of agricultural management.
- Development of a 2-DoF antenna radiation measurement systemPublication . Leme, Mauro; Coelho, J.A.B.; Coelho, João PauloUnderstanding antenna radiation patterns is crucial for optimizing wireless communication systems. Although simulation tools predict radiation patterns during development, environmental conditions in real-world settings substantially influence outcomes. Commercial measurement systems, though precise, are often prohibitively expensive for education. This work presents a low-cost, two-axis computerised system for measuring antenna radiation patterns at 868 MHz, integrating Arduino-based control, stepper motors, and power sensors. Tested with a Yagi-Uda antenna, it yields results consistent with simulations, serving as a practical tool for telecommunications classes. By enabling real-time visualization, this mechatronic platform enhances student understanding of antenna behaviour. Designs will be shared openly to support replication.
- Los números del envejecimiento demográfico en PortugalPublication . Praça, Lídia GalvãoThe world population is aging and all countries in the world are witnessing an increase in the number and proportion of elderly people in their population. The number of people aged 60 or over is growing faster than all younger age groups, a phenomenon known as demographic aging. This phenomenon, although widespread, occurs at different rates, depending on the region of the globe. For example, Europe has the highest percentage of the population aged 60 or over (25%), according to reports produced by the UN. Divergence in values can also be found when the analysis is done by country. Knowing that Portugal currently has one of the highest rates of aging within the European Union, this work aims to analyze its evolution, over decades, since 1960, in an attempt to subsequently establish a causal relationship with factors recognized in the literature as having an impact on aging. We chose to carry out this study based on two aging indicators, the “youth dependency index” which expresses the relationship between the young population (up to 14 years old) and the working-age population (15 to 64 years old) and the “elderly dependency index” expressed by the relationship between the elderly population (over 65 years old) and the working-age population, both published by PORDATA (base of certified statistics on Portugal, its Municipalities and Europe). It was possible to identify and compare moments of more pronounced variations that occurred over time, contributing to future lines of investigation and a better understanding of this phenomenon, which is so impactful for any Economy.
- Aproveitamento de energia excedente em usinas fotovoltaicas causada por clipping: comparação de eficiência entre soluções de armazenamento em bateria e hidrogênio verdePublication . Horn, Beatriz Souza; Brito, Paulo Sérgio; Soares, OrlandoEm dimensionamentos de usinas fotovoltaicas, é possível realizar um sobredimensionamento, adicionando uma potência pico instalada de módulos fotovoltaicos DC (Corrente Contínua) superior à potência nominal AC (Corrente Alternada) do inversor. Com isso, em momentos de baixa irradiância, os módulos fotovoltaicos adicionais vão minimizar esse impacto, maximizando a energia total produzida. Contudo, em momentos de alta irradiância, como os inversores não são capazes de transformar toda energia DC em AC pela limitação da potência nominal instalada, essa energia é perdida. Esse fenômeno pode ser chamado de clipping, já que há um corte na curva de geração. Para contornar essa questão, os agentes geradores e comercializadores de energia solar fotovoltaica buscam soluções de mercado para aproveitamento da energia excedente gerada. Uma das soluções mais procuradas é a de armazenamento de energia, para posterior injeção na rede, em momentos de baixa irradiância. Convencionalmente, são utilizadas baterias. Porém, há outros métodos de armazenamento existentes, como o do hidrogênio. Em específico, o hidrogênio verde, que é o hidrogênio produzido por eletrólise da água, através de uma fonte renovável, em corrente contínua. Nesse sentido, o hidrogênio torna-se uma opção para análise do processo de carga e descarga em sua cadeia de produção e transformação até o armazenamento, pois apresenta características aplicáveis para usinas fotovoltaicas. Portanto, o objetivo desse trabalho é comparar, ao longo de 25 anos de vida útil de uma usina fotovoltaica, a eficiência dos sistemas de armazenamento em bateria em relação ao sistema de armazenamento em hidrogênio verde, como opções de solução de contorno para evitar perdas de energia excedente ocasionadas pelo clipping.
- Enhancing realism in 3D mapping through drone-based photogrammetry and animated elementsPublication . Deusdado, Leonel; Martins, A.; Rocha, JoãoOver time, society has increasingly adopted technology across various sectors and at different levels. Technological advancements have enabled the substitution of traditional models with animated 3D representations that offer higher levels of realism. This study explores the integration of drone-based photogrammetry with 3D modeling and animation techniques to produce realistic representations of outdoor environments, mapping the IPB-ESTIG campus, highlighting the integration of drones, software tools like Unity, and animation techniques for creating immersive environments. The objective was to provide a dynamic representation of the campus using photogrammetric methods and incorporating animated elements such as people and birds, allowing users to interact with the simulated environment. The challenges, methods, and results of this project demonstrate the viability of integrating photogrammetry, modeling, and animation to develop realistic 3D campus models and a more immersive experience in applications like urban planning, architecture, and environmental monitoring.
- Health evaluation over paver block pavements based on ISO 2631-1 and NHO 09 regulations.Publication . Wolf, Matheus do Prado; Gidrão, Gustavo de Miranda Saleme; Kripka, Moacir; Bisconsini, Danilo Rinaldi; Minhoto, ManuelIt is essential that pavements offer traffic flow, comfort and no health risks for their users. Still, it is important to be aware of the pollution created in their produce chain and drainage capacity. Conventional flexible and rigid pavements have a considerable limited drainage performance besides being not sustainable in their production. A solution for pathways that are frequently neglected, usually low-volume pathways (streets and roads) and environment friendly are paver blocks pavements. Paver blocks are sustainable and have a good performance in the drainage of precipitation, furthermore. This article aims though ISO 2631-1 and NHO 09 evaluations of vibrations over paver blocks on low-volume pathways to check if the evaluations resulting conditions are similar, to compare ISO 2631-1 values obtained with literature values and discuss if different arrangements of paver blocks can produce more vibrations. The equipment used consists of a car support to insert the cellphone which recorded vibrations though its accelerometer and a simple utility trailer towable to the car used to measure vibrations on the same pathway afterward. Other purpose is verify if there is a correlation between the last one and the support car, offering a model that is not dependable on the car model to observe the level of vibrations transmitted by the paver block pavement. This paper reached that NHO-09 classified milder than ISO 2631-1 the performance of pavements, possible relation of higher vibrations with the arrangement of paver and values of vibrations relatable to the literature.