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Análise comparativa de métodos de detecção automática de mensagens ofensivas em textos curtos e ruidosos
(Universidade Federal de São Carlos, 2025-05-06) Maricondi, Thiago Nacrur; Vincenzi, Auri Marcelo Rizzo; https://lattes.cnpq.br/0611351138131709; https://orcid.org/0000-0001-5902-1672; https://lattes.cnpq.br/1237234894241914
With the increasing use of social media and the ease of access to digital content—especially among children and adolescents—there has been a significant rise in cases of cyberbullying and online harassment in recent years. In response, several content moderation tools have been developed, such as comment filters, reporting systems, and user profiles dedicated to moderation. However, due to the vast amount of information constantly generated on social media platforms, manual moderation has become impractical, highlighting the importance of automated moderation in reducing the incidence of digital crimes. This work addresses the automatic identification of aggressive behavior in offensive messages found in short and noisy texts using machine learning and deep learning algorithms. A public dataset extracted from platform X was used, containing 20,001 sentences labeled as aggressive 39.1% or non-aggressive 60.9%. Supervised learning models were trained using stratified cross-validation, employing text preprocessing techniques and various algorithms, including BERT, FastText, and ensemble methods, with the goal of assessing the effectiveness of these approaches in the automatic detection of textual aggressiveness. The results showed that the BERT and FastText models achieved excellent recall scores, reaching 96.5% and 95.8%, respectively, significantly outperforming the baseline model in detecting offensive messages.
Entre fases: práticas informacionais durante a menopausa
(Universidade Federal de São Carlos, 2025-05-06) Andrikonis, Juliana Buzinaro; Furnival, Ariadne Chloe Mary; https://lattes.cnpq.br/1291482506649810; https://orcid.org/0000-0002-2344-4400; https://lattes.cnpq.br/2121898429151597; https://orcid.org/0009-0008-9520-4714
The presented dissertation focuses on investigating the information practices of women experiencing at least one perimenopausal stages, a process that approximately 18% of the Brazilian population has gone through or will go through, and which is an expected experience for all cisgender women. Despite its recurrence, the perimenopause is still surrounded by insecurities and uncertainties, especially regarding the management of symptoms that affect quality of life, such as hot flashes, insomnia, and emotional changes, as well as controversies surrounding hormone replacement therapy. The scarcity of accessible information and the persistence of taboos on the subject exacerbate these challenges, making it difficult for women to access resources that could help them better navigate this phase. In this context, this research aims to identify the informational practices of these women, contributing to an interdisciplinary understanding between Information Science and the Health field. To support the study, we rely on four theories from Information Science: Brenda Dervin’s Sense-Making approach, which explores how individuals construct meaning in situations of uncertainty; Reijo Savolainen’s Everyday Life Information Seeking model, which focuses on how people seek information in their daily lives; Elfreda Chatman’s Small World concept, which analyzes how groups of individuals share information in specific environments; and finally, Pamela McKenzie’s informational practices approach, which examines how people interact with information in their social context. The research adopts a descriptive, exploratory, and cross-sectional approach, with qualitative data collection through the survey method, using a questionnaire. In addition to primary data collection, bibliographic materials were used, obtained from guidance recommendations, references from foundational works, and searches in scientific databases such as Scopus, PubMed, SciELO, and Web of Science, using search expressions specifically developed for this study. The results are based on 208 valid responses, with most participants located in the state of São Paulo, identifying as white, and holding postgraduate degrees. Although the majority of respondents belong to a socially privileged group, we also obtained responses from women with different socioeconomic backgrounds, enriching the findings. These results suggest that many women indeed experience doubts, difficulties in accessing evidence-based health information, and insecurities during the perimenopausal phase. Among them, most seek guidance from healthcare professionals to address these concerns. However, some respondents expressed frustration with the lack of adequate attention and the inability of healthcare professionals to provide proper guidance. Another significant finding is that women frequently turn to other women for information about menopause, whether through virtual groups, friends, or family members. This study leads us to conclude that the healthcare field could greatly benefit from integrating information services through the lens of Information Science. This approach would provide more adequate support for individuals in various health situations, especially for those experiencing some degree of social vulnerability.
Concrete masonry structures: numerical modeling, seismic performance, and building applications
(Universidade Federal de São Carlos, 2025-05-06) Palhares, Rodolfo de Azevedo; Graham Shrive, Nigel; Parsekian, Guilherme Aris; https://lattes.cnpq.br/7798651726059215; https://orcid.org/0000-0002-5939-2032; https://lattes.cnpq.br/6274536481818193; https://orcid.org/0000-0002-5271-7447
Partially grouted reinforced masonry (PGRM) structures are widely used worldwide, especially in regions with low to moderate seismicity, due to their economic and structural advantages. The nonlinear behavior of PGRM walls is complex, as it is influenced by the interaction between grouted/reinforced and ungrouted regions, which differ in stiffness and introduce non-uniformity in the cross-section. Additionally, factors such as aspect ratio, cross-sectional area, material properties, reinforcement detailing, and axial load significantly influence the nonlinear response. At the building level, further complexities arise from layout configurations, horizontal diaphragm interactions (slabs), and axial load distributions, making it insufficient to rely solely on isolated wall responses to predict overall performance. This thesis addresses these complexities by developing numerical modeling approaches to simulate multi-storey PGRM walls, with the aim of evaluating the seismic performance of building systems and propose practical design recommendations. The research comprises four independent but interconnected studies, each presented as a separate chapter in this thesis. In the first study, a simplified macro-modeling approach is evaluated to simulate the nonlinear in-plane behavior of PGRM walls with vertical reinforcement concentrated at the pier ends. The model, validated based on experimental data from four walls tested by the author’s research group, accurately predicted global behavior, including force-displacement responses and damage mechanisms, while presenting low computational costs. However, further refinement and validation are needed to address additional detailing scenarios, such as cases where vertical reinforcement and grouted regions are not continuous across stories or where reinforcement and grout are distributed non-uniformly along the wall length. In the second study, a unified finite element-based modeling strategy is introduced that combines macro-modeling for grouted regions and simplified micro-modeling for ungrouted regions. This approach facilitates the accurate simulation of various masonry wall typologies, including unreinforced masonry (URM), fully grouted reinforced masonry (FGRM), and PGRM. The numerical model effectively captured the nonlinear response across different experimental cases, and sensitivity analyses identified key parameters that influence numerical accuracy. This study provides valuable insights for future applications in the simulation of in-plane loaded masonry structures. The third study extends the unified modeling approach to investigate the seismic behavior of multi-storey PGRM walls within three-dimensional structural systems. Nonlinear static (pushover) analysis results revealed the significant impact of orthogonal walls (flanges), aspect ratios, axial load levels, and vertical reinforcement arrangements. Flanges have been shown to increase lateral stiffness and force capacity, higher axial loads enhance force capacity but reduce ductility, and a greater number of stories decreases stiffness and increases ultimate displacement. The vertical reinforcement concentrated at the wall ends exhibited an efficiency comparable to uniformly distributed reinforcement, demonstrating it as a suitable alternative. In the fourth study, the seismic performance of two real-world reinforced masonry buildings representative of Canadian (B1) and Brazilian (B2) practices is examined. Using a multi-step methodology that integrates eigenvalue analyses and pushover simulations, the study highlighted the critical role of structural layout in the seismic performance of buildings. Balanced wall distribution and flange contributions significantly improved performance. Notably, building B2, despite lacking explicit seismic design provisions and detailing, outperformed B1 under higher seismic demands, underlining the importance of optimized structural layouts in enhancing seismic performance. Overall, this thesis establishes a comprehensive framework for evaluating and improving the seismic performance of concrete masonry buildings. The proposed modeling approaches, validated based on experimental data, provide support for analyzing masonry systems and informing potential updates to seismic design standards. The findings emphasize the importance of regional adaptations in building design and structural layout optimization to achieve better seismic performance.