ESTG - Artigos em revistas internacionais
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Percorrer ESTG - Artigos em revistas internacionais por Objetivos de Desenvolvimento Sustentável (ODS) "10:Reduzir as Desigualdades"
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- Abordagem baseada em Algoritmos Genéticos para deteção de vulnerabilidades de SQL Injection em Aplicações Web PHPPublication . Baptista, Kevin; Bernardino, Anabela Moreira; Bernardino, Eugénia MoreiraHoje em dia, existe uma maior preocupação com a segurança no desenvolvimento de aplicações web. No entanto, ainda existem muitos ataques a este tipo de aplicações, perpetuados por hackers que se aproveitam das vulnerabilidades destas aplicações. Estas vulnerabilidades podem estar associadas a inúmeros fatores, desde configurações incorretas, falhas nas políticas de segurança, sistemas ou componentes desatualizados ou problemas diretamente associados ao código desenvolvido. Os ataques a aplicações web tem como resultado perda de informação privilegiada. Para mitigar este problema, existem varias ferramentas automatizadas que permitem auxiliar profissionais da área a identificar estas vulnerabilidades. No entanto, manter estas ferramentas atualizadas com a evolução tecnológica tem-se demonstrado um desafio. Neste artigo, propomos uma abordagem para detetar vulnerabilidades de SQL Injection no código-fonte de varias aplicações web PHP, usando Algoritmos Genéticos (AG). Os resultados obtidos mostram a eficiência do AG em relação a outras ferramentas existentes.
- Active reflection coefficients characterization system for multiple input multiple output antennasPublication . Jordão, Marina; Belo, Daniel; Caldeirinha, Rafael F. S.; Oliveira, Arnaldo S. R.; Carvalho, Nuno B.The main objective of this study is to present a characterization system that can be used to measure the active reflection coefficient of each port of the multiple input multiple output (MIMO) antennas, when the main beam is steered to an intended direction. Since MIMO systems are composed of antennas with several elements and each antenna element is connected to a power amplifier, an active component, the beamforming will contribute to the mismatch of each branch. To this extent, a calibrated measurement system has been implemented using off-the-shelf software defined radio and designed to effectively extract such coefficients, when all the ports are simultaneously excited. Results for linear and planar MIMO antenna arrays have been experimentally obtained for several beam directions and the impact of beamforming on each element of the antenna is presented and compared to simulated results. Additionally, their behaviour was also assessed when some of the radiation elements are deliberately disconnected, mimicking those not working properly.
- An Annotated Corpus of Crime-Related Portuguese Documents for NLP and Machine Learning ProcessingPublication . Carnaz, Gonçalo; Antunes, Mário; Nogueira, Vitor BeiresCriminal investigations collect and analyze the facts related to a crime, from which the investigators can deduce evidence to be used in court. It is a multidisciplinary and applied science, which includes interviews, interrogations, evidence collection, preservation of the chain of custody, and other methods and techniques of investigation. These techniques produce both digital and paper documents that have to be carefully analyzed to identify correlations and interactions among suspects, places, license plates, and other entities that are mentioned in the investigation. The computerized processing of these documents is a helping hand to the criminal investigation, as it allows the automatic identification of entities and their relations, being some of which difficult to identify manually. There exists a wide set of dedicated tools, but they have a major limitation: they are unable to process criminal reports in the Portuguese language, as an annotated corpus for that purpose does not exist. This paper presents an annotated corpus, composed of a collection of anonymized crime-related documents, which were extracted from official and open sources. The dataset was produced as the result of an exploratory initiative to collect crime-related data from websites and conditioned-access police reports. The dataset was evaluated and a mean precision of 0.808, recall of 0.722, and F1-score of 0.733 were obtained with the classification of the annotated named-entities present in the crime-related documents. This corpus can be employed to benchmark Machine Learning (ML) and Natural Language Processing (NLP) methods and tools to detect and correlate entities in the documents. Some examples are sentence detection, named-entity recognition, and identification of terms related to the criminal domain.
- Application of curcuminoids in inflammatory, neurodegenerative and aging conditions - Pharmacological potential and bioengineering approaches to improve efficiencyPublication . Lagoa, Ricardo; Rajan, Logesh; Violante, Cristiana; Babiaka, Smith B.; Marques da Silva, Dorinda; Kapoor, Bhupinder; Reis, Flávio; Atanasov, Atanas G.Curcumin, a natural compound found in turmeric, has shown promise in treating brain-related diseases and conditions associated with aging. Curcumin has shown multiple anti-inflammatory and brain-protective effects, but its clinical use is limited by challenges like poor absorption, specificity and delivery to the right tissues. A range of contemporary approaches at the intersection with bioengineering and systems biology are being explored to address these challenges. Data from preclinical and human studies highlight various neuroprotective actions of curcumin, including the inhibition of neuroinflammation, modulation of critical cellular signaling pathways, promotion of neurogenesis, and regulation of dopamine levels. However, curcumin’s multifaceted effects - such as its impact on microRNAs and senescence markers - suggest novel therapeutic targets in neurodegeneration. Tetrahydrocurcumin, a primary metabolite of curcumin, also shows potential due to its presence in circulation and its anti-inflammatory properties, although further research is needed to elucidate its neuroprotective mechanisms. Recent advancements in delivery systems, particularly brain-targeting nanocarriers like polymersomes, micelles, and liposomes, have shown promise in enhancing curcumin’s bioavailability and therapeutic efficacy in animal models. Furthermore, the exploration of drug-laden scaffolds and dermal delivery may extend the pharmacological applications of curcumin. Studies reviewed here indicate that engineered dermal formulations and devices could serve as viable alternatives for neuroprotective treatments and to manage skin or musculoskeletal inflammation. This work highlights the need for carefully designed, long-term studies to better understand how curcumin and its bioactive metabolites work, their safety, and their effectiveness.
- Aprendizagem Interorganizacional e Capacidade Absortiva: Investigação em Pequenas e Médias EmpresasPublication . Cassol, Alessandra; Marietto, Márcio L.; Tonial, Graciele; Werlang, Nathalia B.Objetivo: Esta pesquisa analisa a influência da aprendizagem interorganizacional (AIO) sobre a capacidade absortiva (Acap), potencial (Pacap) e realizada (Racap), no ambiente de pequenas e médias empresas (PMEs). Originalidade/valor: O estudo contribuiu para o entendimento e a expansão das pesquisas da AIO operacionalizadas por meio dos elementos da Acap. A compreensão desses elementos é fundamental para o desenvolvimento de novas competências das PMEs brasileiras e/ou de países emergentes, imersas em setores dinâmicos e de alta mobilidade tecnológica, para se adaptarem e desenvolverem novas capacidades dinâmicas. Design/metodologia/abordagem: A pesquisa foi realizada por meio de uma survey em uma amostra de 215 PMEs do setor de tecnologia da informação e comunicação (TIC) no estado de Santa Catarina, Brasil. Os dados foram analisados a partir da técnica de modelagem de equações estruturais. Resultados: Os resultados demonstraram que as relações de AIO são capazes de influenciar o desenvolvimento de novas competências e possuem forte influência sobre o desenvolvimento da Acap. A habilidade das organizações em adquirir, assimilar, aplicar e internalizar os conhecimentos disponíveis no setor, por meio de relações interorganizacionais, foi fundamental para a adaptação e sobrevivência.
- Artificial intelligence applied to the stone manufacturing industry: A systematic literature reviewPublication . Santos Silva, Alexandre; Antunes, Carolina; Miragaia, Rolando; Costa, Rogério Luís C.; Silva, Fernando; Ribeiro, JoséNatural stone has long been used in construction, as its properties provide functional and visual value, and the natural stone market currently holds significant importance in the global economy. It is important to consider integrating new technologies in the production chain to aid the industry in moving forward, increasing profit margins and reducing wasted material. This article reviews recent trends in using Artificial Intelligence and Machine Learning techniques in the industry between 2017 and 2024, following a methodology for Systematic Literature Reviews in computer science. It was found that extensive research has been conducted on the subject of tile classification, with solid solutions proposed, achieving results that can be considered robust enough for industrial application. Other subjects comprise tasks regarding stone cutting and defect detection, as well as variable prediction, and quarry activity monitoring. Some authors propose solutions to integrate new technologies into the complete production chain. While more research needs to be done on specific subjects, this review provides a solid first step to future research.
- Artificial Intelligence-Driven User Interaction with Smart Homes: Architecture Proposal and Case StudyPublication . Lemos, João; Ramos, João; Gomes, Mário; Coelho, PauloThe evolution of Smart Grids enabled the deployment of intelligent and decentralized energy management solutions at the residential level. This work presents a comprehensive Smart Home architecture that integrates real-time energy monitoring, appliance-level consumption analysis, and environmental data acquisition using smart metering technologies and distributed IoT sensors. All collected data are structured into a scalable infrastructure that supports advanced Artificial Intelligence (AI) methods, including Large Language Models (LLMs) and machine learning, enabling predictive analysis, personalized energy recommendations, and natural language interaction. Proposed architecture is experimentally validated through a case study on a domestic refrigerator. Two series of tests were conducted. In the first phase, extreme usage scenarios were evaluated: one with intensive usage and another with highly restricted usage. In the second phase, normal usage scenarios were tested without AI feedback and with AI recommendations following them whenever possible. Under the extreme scenarios, AI-assisted interaction resulted in a reduction in daily energy consumption of about 81.4%. In the normal usage scenarios, AI assistance resulted in a reduction of around 13.6%. These results confirm that integrating AI-driven behavioral optimization within Smart Home environments significantly improves energy efficiency, reduces electrical stress, and promotes more sustainable energy usage.
- Augmented Reality: An Enhancer for Higher Education Students in Math's Learning?Publication . Coimbra, MMath. Teresa; Cardoso, Teresa; Mateus, ArturIn this text, we intend to answer to the following question: is Augmented Reality an enhancer for Higher Education students in math's learning? For this purpose, we define augmented reality and present a state of the art mapped mainly by studies that focus AR in educational contexts. We also describe our research, including methodological aspects in data collection and the creation of 3D contents in AR. Then, we synthesize the analysis of some preliminary data, briefly presenting perceptions and practices of students in math's learning with AR contents. Finally, we conclude that the challenges that are nowadays put to teaching methods, acquisition and subsequent knowledge consolidation may be met, to some extent, by the application of available technologies. These, in turn, should enhance a more complete understanding of contents, leading to knowledge endogenization and also to the internalization of more sustained competencies. Among those technologies, we highlight augmented reality since it can encourage motivation, comprehension and a higher involvement with the contents to be learned. Thus, it may increase the use of information and the access to knowledge, improving digital and info-inclusion.
- Automated design of microwave discrete tuning differential capacitance circuits in Si‐integrated technologiesPublication . Mendes, Luís; Pires, E. J. Solteiro; Vaz, João C.; Rosário, Maria J.; Oliveira, P. B. de Moura; Machado, J. A. TenreiroA genetic algorithm used to design radio-frequency binary-weighted differential switched capacitor arrays (RFDSCAs) is presented in this article. The algorithm provides a set of circuits all having the same maximum performance. This article also describes the design, implementation, and measurements results of a 0.25 μm BiCMOS 3-bit RFDSCA. The experimental results show that the circuit presents the expected performance up to 40 GHz. The similarity between the evolutionary solutions, circuit simulations, and measured results indicates that the genetic synthesis method is a very useful tool for designing optimum performance RFDSCAs.
- Automatic Transcription of Polyphonic Piano Music Using Genetic Algorithms, Adaptive Spectral Envelope Modeling, and Dynamic Noise Level EstimationPublication . Reis, Gustavo; Fernandez de Vega, Francisco; Ferreira, AníbalThis paper presents a new method for multiple fundamental frequency (F0) estimation on piano recordings. We propose a framework based on a genetic algorithm in order to analyze the overlapping overtones and search for the most likely F0 combination. The search process is aided by adaptive spectral envelope modeling and dynamic noise level estimation: while the noise is dynamically estimated, the spectral envelope of previously recorded piano samples (internal database) is adapted in order to best match the piano played on the input signals and aid the search process for the most likely combination of F0s. For comparison, several state-of-the-art algorithms were run across various musical pieces played by different pianos and then compared using three different metrics. The proposed algorithm ranked first place on Hybrid Decay/Sustain Score metric, which has better correlation with the human hearing perception and ranked second place on both onset-only and onset–offset metrics. A previous genetic algorithm approach is also included in the comparison to show how the proposed system brings significant improvements on both quality of the results and computing time.