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Publications

2023

Analysis of skewing effects on radial force for different topologies of switched reluctance machines: 6/4 SRM, 8/6 SRM, and 12/8 SRM

Authors
Touati, Z; Araújo, RE; Mahmoud, I; Khedher, A;

Publication
U.Porto Journal of Engineering

Abstract
Reducing vibration and noise in electrical machines for a given application is not a straightforward task, especially when the application imposes some restrictions. There are many techniques for reducing vibration based on design or control. Switched reluctance motors (SRMs) have a double-saliency structure, which results in a radial pulsation force. Consequently, they cause vibration and acoustic noise. This paper investigates the correlation between the radial force and the skew angle of the stator and/or rotor circuits. We computed the analysis from two-dimensional (2D) transient magnetic finite-element analysis (FEA) of three machine topologies, namely the 12/8 three-phase SRM, the 6/4 three-phase SRM and the 8/6 four-phase SRM. Compared to SRM, these topologies have the same basic dimensions (stator outer diameter, rotor outer diameter, and length) and operate in the same magnetic circuit saturation. The flux linkage and torque characteristics of the different motors are presented. The radial force distributed on the stator yoke under various skewing angles is studied extensively by FEA for the three machines. It is also demonstrated the effect of skewing angles in the reduction of radial force without any reduction in torque production. © 2023, Universidade do Porto - Faculdade de Engenharia. All rights reserved.

2023

Challenging Beat Tracking: Tackling Polyrhythm, Polymetre, and Polytempo with Human-in-the-Loop Adaptation

Authors
Pinto, AS; Bernardes, G; Davies, MEP;

Publication
Music and Sound Generation in the AI Era - 16th International Symposium, CMMR 2023, Tokyo, Japan, November 13-17, 2023, Revised Selected Papers

Abstract
Deep-learning beat-tracking algorithms have achieved remarkable accuracy in recent years. However, despite these advancements, challenges persist with musical examples featuring complex rhythmic structures, especially given their under-representation in training corpora. Expanding on our prior work, this paper demonstrates how our user-centred beat-tracking methodology effectively handles increasingly demanding musical scenarios. We evaluate its adaptability and robustness through musical pieces that exhibit rhythmic dissonance, while maintaining ease of integration with leading methods through minimal user annotations. The selected musical works—Uruguayan Candombe, Colombian Bambuco, and Steve Reich’s Piano Phase—present escalating levels of rhythmic complexity through their respective polyrhythm, polymetre, and polytempo characteristics. These examples not only validate our method’s effectiveness but also demonstrate its capability across increasingly challenging scenarios, culminating in the novel application of beat tracking to polytempo contexts. The results show notable improvements in terms of the F-measure, ranging from 2 to 5 times the state-of-the-art performance. The beat annotations used in fine-tuning reduce the correction edit operations from 1.4 to 2.8 times, while reducing the global annotation effort to between 16% and 37% of the baseline approach. Our experiments demonstrate the broad applicability of our human-in-the-loop strategy in the domain of Computational Ethnomusicology, confronting the prevalent Music Information Retrieval (MIR) constraints found in non-Western musical scenarios. Beyond beat tracking and computational rhythm analysis, this user-driven adaptation framework suggests wider implications for various MIR technologies, particularly in scenarios where musical signal ambiguity and human subjectivity challenge conventional algorithms. © 2025 Elsevier B.V., All rights reserved.

2023

The influential role of austerity in normalising sustainable consumption

Authors
O'Loughlin D.; McEachern M.G.; Szmigin I.; Karantinou K.; Barbosa B.; Lamprinakos G.; Fernández-Moya M.E.;

Publication
Research Handbook on Ethical Consumption

Abstract

2023

Designing a Skilled Soccer Team for RoboCup: Exploring Skill-Set-Primitives through Reinforcement Learning

Authors
Abreu, M; Reis, LP; Lau, N;

Publication
CoRR

Abstract

2023

CuraZone: The tool to care for populated areas

Authors
Jardim, R; Quiliche, R; Chong, M; Paredes, H; Vivacqua, A;

Publication
SOFTWARE IMPACTS

Abstract
The COVID-19 pandemic highlighted the inadequate readiness of numerous nations to address diseases that could potentially evolve into epidemics or pandemics, posing risks to health systems and supply chains. Statistical analysis and predictive models were developed to manage COVID-19 and other diseases that harm public health. However, few public-policy decision-support tools are documented in the literature, although several governments have created them. In line with the previous developments, this tool uses socioeconomic features to model the COVID-19 province's mortality rates. This paper presents a tool to predict the mortality rate of a province using supervised learning techniques, named CuraZone. This tool was validated using 196 provinces in Peru for training and considering 31 characteristics. The tool displays the dataset's most essential characteristics, shows the country's mean square error (MSE), and predicts a province's mortality rate. In addition, the tool contributes to the field of Explainable AI (XAI), as it shows the importance of each feature. Highlighted contributions of this work include the support for the decision-making of governments or stakeholders in epidemics, providing the source code in an open and reproducible way, and the estimated mortality rate for specific populations of a neighborhood, city, or country.

2023

A review on chatbot personality and its expected effects on users

Authors
Ferreira M.; Barbosa B.;

Publication
Trends, Applications, and Challenges of Chatbot Technology

Abstract
The main objectives of this chapter are to provide an overview of chatbot personality dimensions and to analyze the expected impacts on user behavior. To accomplish these objectives, the chapter provides a detailed review of the main contributions in the literature regarding this topic. It highlights the chatbot personality characteristics that are expected to foster user satisfaction, trust, loyalty, and engagement. This information is useful for both practitioners and researchers, particularly related to customer service, as it provides clear guidance on what characteristics to incorporate in chatbots and on what factors need to be further studied in the future.

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