ESTCB - Artigos em revistas com arbitragem científica
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- A study on acoustic bird detection in the context of smart agriculturePublication . Cardoso, Fábio; Carvalho, Daniel; Gaspar, Pedro Dinis; Soares, V.N.G.J.; Caldeira, J.M.L.P.Bird attacks on crops represent one of the main challenges faced by farmers to make a farm profitable and sustainable. This challenge requires a paradigm shift from old, traditional, ineffective methods, towards the incorporation of smart farming technologies. Intelligent or precision agriculture contributes to the effective and efficient management of resources and, consequently, an increase in production. This work first reviews projects, techniques and methods that can be used for bird species detection and identification based on their sound. Then, a performance evaluation study is conducted on two different approaches that can be employed for the development of a smart bird deterrence solution. Their strengths and limitations are highlighted. The findings can be used as a foundation for future research in this area.
- Dynamic energy-aware anchor optimization for contact-based indoor localization in MANETsPublication . Jesús-Azabal, Manuel; Zheng, Meichun; Soares, V.N.G.J.Indoor positioning remains a recurrent and significant challenge in research. Unlike outdoor environments, where the Global Positioning System (GPS) provides reliable location information, indoor scenarios lack direct line-of-sight to satellites or cellular towers, rendering GPS inoperative and requiring alternative positioning techniques. Despite numerous approaches, indoor contexts with resource limitations, energy constraints, or physical restrictions continue to suffer from unreliable localization. Many existing methods employ a fixed number of reference anchors, which sets a hard balance between localization accuracy and energy consumption, forcing designers to choose between precise location data and battery life. As a response to this challenge, this paper proposes an energy-aware indoor positioning strategy based on Mobile Ad Hoc Networks (MANETs). The core principle is a self-adaptive control loop that continuously monitors the network’s positioning accuracy. Based on this real-time feedback, the system dynamically adjusts the number of active anchors, increasing them only when accuracy degrades and reducing them to save energy once stability is achieved. The method dynamically estimates relative coordinates by analyzing node encounters and contact durations, from which relative distances are inferred. Generalized Multidimensional Scaling (GMDS) is applied to construct a relative spatial map of the network, which is then transformed into absolute coordinates using reference nodes, known as anchors. The proposal is evaluated in a realistic simulated indoor MANET, assessing positioning accuracy, adaptation dynamics, anchor sensitivity, and energy usage. Results show that the adaptive mechanism achieves higher accuracy than fixed-anchor configurations in most cases, while significantly reducing the average number of required anchors and their associated energy footprint. This makes it suitable for infrastructure-poor, resource-constrained indoor environments where both accuracy and energy efficiency are critical.
- Modular microservices architecture for generative music integration in digital audio workstations via VST pluginPublication . Raposo, Adriano N.; Soares, V.N.G.J.This paper presents the design and implementation of a modular cloud-based architecturethat enables generative music capabilities in Digital audioWorkstations through a MIDI microservices backend and a user-friendly VST plugin frontend. The system comprises a generative harmony engine deployed as a standalone service, a microservice layer that orchestrates communication and exposes an API, and a VST plugin that interacts with the backend to retrieve harmonic sequences and MIDI data. Among the microservices is a dedicated component that converts textual chord sequences into MIDI files. The VST plugin allows the user to drag and drop the generated chord progressions directly into a DAW’sMIDI track timeline. This architecture prioritizes modularity, cloud scalability, and seamless integration into existing music production workflows, while abstracting away technical complexity from end users. The proposed system demonstrates how microservice-based design and cross-platform plugin development can be effectively combined to Support generative music workflows, offering both researchers and practitioners a replicable and extensible framework.
- Phrase-oriented generative rhythmic patterns for jazz solosPublication . Raposo, Adriano N.; Soares, V.N.G.J.This study introduces a novel generative approach for crafting phrase-oriented rhythmic patterns in jazz solos, leveraging statistical analyses of a comprehensive corpus, the Weimar Jazz Database. Jazz solos, celebrated for their improvisational complexity, require a delicate interplay between rhythm and melody, making the generation of authentic rhythmic patterns a challenging task. This work systematically explores the relationships among rhythmic elements, including phrases, beats, divisions, and patterns. The generative method employs a Markov chain framework to synthesize rhythmic divisions and patterns, ensuring stylistic coherence and diversity. An extensive evaluation compares original and generated datasets through statistical and machine learning metrics, validating the generative model’s ability to replicate key rhythmic characteristics while fostering innovation. The findings underscore the potential of this approach to contribute significantly to the fields of computational creativity and algorithmic music composition, providing a robust tool for generating compelling jazz solos.
- Avaliação do nível de contaminação nos sedimentos de cursos de água do Sistema Mineiro de Caveira (Grândola)Publication . Silva, R. da; Fonseca1, R.; Araújo, J. F.; Silva, N.; Albuquerque, M.T.D.O presente trabalho, inserido no Projeto GeoMatRe, visa o levantamento das condições mais atualizadas no que toca aos parâmetros físico-químicos numa mina de drenagem ácida. Uma situação crítica que ocorre na área mineira de Caveira, em Grândola, Portugal, abandonada desde a década de 60 do século passado. O objetivo passa por analisar as condições de contaminação de Elementos Potencialmente Tóxicos (EPT) nos sedimentos que ocorrem quer em fases móveis e dissolvidas na água intersticial dos sedimentos, quer em fases mais imóveis. Neste trabalho é realizada uma caracterização geral da área do sistema mineiro, verificando-se um nível de contaminação da área, através da análise do Índice de Geoacumulação (IGEO) e do Fator de Enriquecimento (FE), onde os elementos Cu, Pb, Zn, As e Hg demonstram ser os principais EPT’s na região, apresentando valores, em alguns dos casos, milhares de vezes acima dos estipulados pelas normas nacionais.
- Influence of tailings from a sulfide mine on drainage water quality, 60 years after its abandonment. A case study in SW PortugalPublication . Araújo, J.F.; Albuquerque, M.T.D.; Silva, N.; Silva, R. daThe GeoMatRe project aims to find low-cost solutions for water and sediment rehabilitation using raw geomaterials, in abandoned mines of the Iberian Pyritic Belt. One of our case studies is the Caveira mine in southwestern Portugal, where large piles of mining waste, containing significant amounts of metals, record the long history of its exploitation for gold (Au) and silver (Ag). After the exhaustion of its reserves, the extraction of the remaining metals (cooper (Cu), lead (Pb) and zinc (Zn)) and sulphur (S) continued, until its abandonment during the 60s of 20th century. This work has two objectives: (i) to study the influence of mine and mine tailings drainage on water quality by analysing the dissolved and particulate material in drainage waters, and (ii) to determine whether there are differences in the contamination level of these waters according to the different weather conditions of the last two winters.
- Stream sediments geochemistry on the Valongo anticlinal, northern Portugal: Arsenic as a proxy for outlining new exploration targetsPublication . Carvalho1, P.; Albuquerque, M.T.D.; Chambel, L.; Silva, M.; Rocha, F.The Valongo anticline is known for the occurrence of several Sb-Au and As-Au mineral deposits, many of which have been exploited since Roman times. The Sb-Au and As-Au deposits occur in brecciated quartz veins, predominantly trending NE-SW, NNW-SSE, and ENE-WSW, cutting Cambrian to Carboniferous formations. An 801-stream sediment campaign was conducted in this area. Factorial kriging was applied as an interpolation method as it enables the estimation and mapping of the individual spatial components of the variogram. Arsenic (As) was used as a proxy to outline new exploration targets. The results allow the identification of NW-SE and NE-SW alignments as preferential areas for elevated As contents. Future studies will incorporate structural information and the distribution of old mine dumps to achieve higher accuracy in target areas for mining prospection.
- Big data in healthcare: Possibilities and challenges - A systematic literature reviewPublication . Barata, Luís; Louro, João; Afonso, JoãoIn today's world, the extensive use of Big Data emerges as a fundamental component in various sectors, and healthcare is no exception. This article explores the importance of using this data for the continuous improvement of patient care, providing them with a better quality of life. However, for this to happen, several challenges must be overcome, especially in data processing and analysis, and in this sector, it is crucial that their accuracy and integrity are not compromised, as they are related to life and death. In this study, we present a survey of technologies, possibilities, and challenges that arise in this field through a systematic review of various articles with cutting-edge approaches to the subject. Consequently, the advantages of using Big Data in healthcare will be highlighted, as well as the critical need to overcome the inherent challenges to achieve efficient and ethical implementation.
- Classification of anomalies in microservices using an XGboost-based approach with data balancing and hyperparameter tuningPublication . Barata, Luís; Lopes, Eurico; Inácio, Pedro; Freire, MárioMicroservice architecture has emerged as a leading paradigm for decomposing large monolithic applications into smaller, autonomous services. Although this approach offers many advantages, its complexity, distributed nature, and substantial scale create significant challenges for monitoring and anomaly detection. The vast volume of generated data further exacerbates computational load and detection latency, complicating the identification of anomalies. This study analyses the impact of data balancing and hyperparameter tuning on anomaly classification in microservices and introduces ADMXGB - Anomaly Detection in Microservices using XGBoost, a XGBoost-based framework tailored for anomaly detection in microservices that seamlessly integrates data balancing with hyperparameter tuning. We propose guidelines to determine appropriate threshold values that balance sensitivity with false positives, and show that the framework is model-agnostic, enabling integration with different machine learning algorithms beyond XGBoost. Validation was performed using a four-stage process encompassing preprocessing, training, validation, and testing. ADMXGB demonstrated improvements in both Accuracy and F1-Score, reaching 99.96% in both metrics on the TraceRCA dataset, outperforming the baseline XGBoost method by a margin of 1.46% in Accuracy and 45.62% in F1-Score. Moreover, ADMXGB achieves reductions in execution time (-86.3%) and memory usage (-21.7%), while maintaining an acceptable CPU overhead. These findings highlight the robustness of ADMXGB in delivering high-accuracy classification in a microservice environment.
- A systematic review on the IEEE 1451 standards: Current status, challenges, and opportunitiesPublication . Spencer, Geoffrey; Torres, Pedro; Gonçalves, Gil M.Given the growth of different manufacturers with diverse hardware/software designs, the growth of transducers functionalities, and rising concerns toward heterogeneity, data security, and trustworthiness, the IEEE Instrumentation and Measurement Society’s Technical Committee 9 on Sensor Technology (IM/ST-TC9-Sensor Technology) supported by the National Institute of Standards and Technology (NIST) formalized the IEEE 1451 family of standards. The standards were developed with the purpose of defining common interfaces for communication within transducers and different systems with plug-and-play (PnP) features, reducing configuration and deployment time. However, in the context of Industry 4.0 (I4.0), the standard fails to address emerging technologies toward Internet of Things (IoT) applications, artificial intelligence (AI), and remaining concerns related to cybersecurity, making it difficult to achieve widespread adoption in the industry sector. This article explores a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 (PRISMA 2020) as a formal systematic literature review guideline to collect and analyze existing knowledge within the scope of the IEEE 1451 standard, examine potential improvements to the standard, and explore future directions to address the constraints identified and open new research opportunities. A total of 53 studies are analyzed, considering publications within the 2019 and 2025 time frame, with data being collected from the Web of Science (WoS), Scopus, and IEEE Xplore scientific database. Findings reveal a strong focus on smart transducers applications in the most diverse domains with interoperability concerns, such as integration with different standards, smart cities applications, environmental monitoring, as well as research on disseminating the adoption of the standards considering both the academic community and industry field while alsosuggesting adaptations/modifications of particular parameters to address evolving applications. Furthermore, a portion of the findings is centered on cybersecurity vulnerabilities and proposes solutions to enhance the robustness and resilience of systems employing the given standards.