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Da estatística ao aprendizado profundo: previsão da taxa de transferência móvel
(Universidade Federal de São Carlos, 2025-10-07) Santos, Estêvão; Almeida, Tiago Agostinho de; https://lattes.cnpq.br/5368680512020633; https://orcid.org/0000-0001-6943-8033; https://lattes.cnpq.br/6220068962241088; Rossi, André; Verdi, Fabio; https://lattes.cnpq.br/5604829226181486; https://lattes.cnpq.br/9143186843657940
The limitations of throughput remain one of the main challenges for mobile network performance. They stem from factors such as capacity constraints, coexistence of multiple technological generations, user mobility, massive integration of the Internet of Things, and unequal access in regions such as Latin America. This variability directly compromises Quality of Service (QoS) and Quality of Experience (QoE), highlighting the need for predictive mechanisms capable of anticipating performance fluctuations, optimizing radio resource allocation, and ensuring efficient connectivity in heterogeneous and complex scenarios. In this context, accurate throughput forecasting plays a central role in adaptive resource management and in maintaining service quality in mobile networks, especially under high-mobility conditions. This work systematically investigates two fundamental dimensions of time series modeling applied to this problem: (i) the contrast between local and global models, and (ii) the impact of including or excluding external covariates. To this end, statistical, machine learning, and deep learning methods are evaluated using real-world mobile network data, where throughput is predicted from channel quality metrics and user speed as potential covariates. Experimental results show that global tree-based models, such as LightGBM, provide the best balance between accuracy, robustness, and efficiency. Furthermore, the use of covariates—mainly related to network quality—proved insufficient to consistently improve predictive performance given the inherent complexity of the forecasting task.
Planejamento da paisagem à conectividade entre Unidades de Conservação: estudo de caso na Bacia Hidrográfica do Sorocaba e Médio Tietê
(Universidade Federal de São Carlos, 2025-10-07) Oehlmeyer, Amanda Santos; Mello, Kaline de; https://lattes.cnpq.br/1974531968891537; Toppa, Rogério Hartung; https://lattes.cnpq.br/0673898572494729; https://lattes.cnpq.br/7508802459977966; Santos, André Cordeiro Alves dos; Zanetti, Natália; https://lattes.cnpq.br/2131880667704281; https://lattes.cnpq.br/0998145230173264
This study analyzed the ecological connectivity among Protected Areas (PAs) in the Sorocaba and Middle Tietê River Basin (UGRHI-10), a region marked by intense urbanization, forest fragmentation, and anthropogenic pressures. The objective was to identify ecological corridors to support landscape planning and guide compensation and forest restoration strategies. To this end, three target species from the Columbidae family were selected, representing different degrees of forest dependence (Geotrygon montana, Leptotila verreauxi, and Patagioenas picazuro), used as models for defining the landscape resistance matrix. The methodology involved an integrated analysis of land cover and land use, PA zoning, interviews with managers, construction of resistance matrices with expert consultation, and modeling of least-cost paths using Linkage Mapper software. The generated routes (i.e., ecological corridors) were spatialized and overlaid with municipal boundaries, and Kernel density analyses were applied to identify connectivity hotspots. In addition, data on the reduction and deficit of Permanent Preservation Areas (PPAs) and Legal Reserves (LRs) were incorporated, enabling the definition of priority areas for environmental compensation. The results revealed a landscape dominated by agriculture (40.17%) and pastures (24.03%), with only 20.38% of forest remnants. Sorocaba stands out as the main urban center and a hub of anthropogenic pressure, while municipalities such as Ibiúna, Piedade, and Bofete hold the largest remnants of native vegetation. The analysis indicated that potential corridors are concentrated in the southeastern and northwestern regions of the basin, connecting larger forest blocks and strategic PAs, although urban and agricultural barriers limit overall landscape permeability. The integration of connectivity routes with environmental deficits highlighted Anhembi, Bofete, Botucatu, Conchas, Itu, Porto Feliz and Tietê as priority municipalities for compensation, guiding restoration actions toward the landscape’s connectivity needs. It is concluded that landscape planning at the regional scale, based on target species and spatial analysis of the resistance matrix, is an effective tool to inform public policies and forest compensation processes. The proposed approach contributes to strengthening ecological connectivity, supporting biodiversity conservation, and promoting greater environmental resilience in the face of anthropogenic pressures and land-use changes in the basin.
Upcycling orange waste into porous carriers for organic phase-change materials
(Universidade Federal de São Carlos, 2025-10-07) Possari, Laís Taguchi; Otoni, Caio Gomide; Budtova, Tatiana; https://lattes.cnpq.br/9403804691367376; https://orcid.org/0000-0001-6734-7381; https://orcid.org/0000-0003-1835-2146; Bettini, Sílvia Helena Prado; https://lattes.cnpq.br/3687551763124327; https://orcid.org/0000-0001-6549-2980; https://lattes.cnpq.br/0698601164327683; https://orcid.org/0000-0002-7167-1966; Lucas, Alessandra de Almeida; Petri, Denise Freitas Siqueira; Bras, Julien; Capron, Isabelle; https://lattes.cnpq.br/9754332336954137; https://lattes.cnpq.br/3916542418374036; https://orcid.org/0000-0002-4762-6030; https://orcid.org/0000-0003-4814-8357; https://orcid.org/0000-0002-2023-5435; https://orcid.org/0000-0001-9145-3803
This thesis investigates the upcycling of orange juice waste biomass into aerogels and cryogels, and their performance as organic carriers of phase-change materials (PCMs). PCMs can store and release thermal energy at nearly constant temperatures during phase transitions, typically solid–liquid, which makes them suitable for passive temperature regulation applications. Aqueous suspensions were prepared by subjecting the whole and fractionated biomass waste (namely peels, pulp, and bagasse) to a citric acid pre-treatment, which promoted the extraction and solubilization of pectin into the liquid phase, and the swelling and fibrillation of the insoluble fraction. The kinetic stability of suspensions was tuned by adjusting preparation parameters (e.g., washing or non-washing, biomass and citric acid contents), enabling the production of homogeneous 3D porous materials using different processing routes. Aerogels were prepared via non-solvent-induced phase separation (with ethanol or acetone) followed by drying with supercritical carbon dioxide, and cryogels via suspension freezing followed by lyophilization. Aerogel beads were also produced by dripping the biomass suspension in ethanol prior to supercritical drying. Porous materials with varied morphologies, textural and mechanical properties, thermal conductivities and biodegradation rates in seawater were obtained. Two organic PCMs, polyethylene glycol and coconut oil, were loaded into obtained porous materials via vacuum-assisted melt impregnation for dimensional stabilization. The resulting phase-change composites were characterized for their thermal behavior and leakage resistance above the PCMs melting temperature, showing that the porous materials’ morphology and compatibility with the PCMs had a decisive impact on their performance as carriers for PCMs.
Revelando o sentimento de pertença com adolescentes a partir de uma pesquisa participativa
(Universidade Federal de São Carlos, 2025-10-07) Speranza, Marina; Cid, Maria Fernanda Barboza; https://lattes.cnpq.br/8595043315867424; https://orcid.org/0000-0002-0199-0670; https://lattes.cnpq.br/4401290437133133; https://orcid.org/0000-0003-1186-1386; Taño, Bruna Lídia; Fernandes, Amanda Dourado Souza Akahosi; Latas, Ángeles Parrila; Jucá, Vládia Jamile dos Santos; Cid, Maria Fernanda Borboza; https://lattes.cnpq.br/0192418247836786; https://lattes.cnpq.br/7901666626822625; https://dialnet.unirioja.es/servlet/autor?codigo=115230; https://lattes.cnpq.br/5114828099080089; https://lattes.cnpq.br/8595043315867424; https://orcid.org/0000-0002-0101-4100; https://orcid.org/0000-0001-8006-8117; https://orcid.org/0000-0003-3393-6537; https://orcid.org/0000-0003-2416-7342; https://orcid.org/0000-0002-0199-0670
This decolonial study seeks to break historical silences and question the notion of a universal knowledge. By confronting the coloniality of knowledge, particularly the myth of scientific neutrality, I acknowledge my own non-neutrality and adopt writing in both the first-person singular and plural. The use of the plural expresses the voices of a collective of adolescents who participated in the investigation as researchers, recognizing them as protagonists of their life processes and the topics that concern them. This choice responds to the need to overcome adult-centered and exclusionary perspectives that have historically marked the production of knowledge about this population. Furthermore, despite advances in the field of child and adolescent mental health, there is still a need to expand knowledge production focused on adolescents, in order to support the design and implementation of effective mental health promotion strategies that recognize their singularities, given the increasing experiences of suffering among adolescents. The sense of belonging has been highlighted as an important element in this debate, as it directly influences adolescents’ mental health. Objectives: To explore, identify, and analyse adolescents’ perspectives on the sense of belonging, examining its relationship with the different contexts in which they are embedded and with mental health. Methodology: The theoretical-methodological framework that underpins this investigation is participatory research, characterized by its commitment to occur democratically and horizontally, and to be conducted WITH the subjects rather than ON them, which already implies a potential for transforming reality. The study took place in a community space located in a socially vulnerable territory. Seven adolescents participated, and their engagement was fostered through creative methodologies and methodological coexistence, also supported by my professional perspective as an occupational therapist and by the principles of Popular Health Education. To produce the data, we used various resources, including poster and mural construction, field trips inside and outside the territory, model-making, photography, and interviews, which stimulated group discussions. I also used field diary records written by myself. Data analysis was conducted collectively and integrated into the production process itself. Results: Data were constructed throughout the process and are organized into three axes. In the first, I describe how adolescents’ participation in the research was constituted. As the research group consolidated, the sense of belonging to the collective also strengthened. This belonging, present from the beginning, acted as a driving force for participation: the more it expanded, the more significant adolescents’ engagement in the investigative process became. In the second axis, I present data emerging from the experience of sharing daily life with adolescents, highlighting how they experienced the community space. We observed that the sense of belonging is reinforced when there are opportunities to play, share food, and move freely. In the final axis, I describe activities developed at a stage of the research when adolescents already had a more solid participation repertoire and demonstrated greater proactivity, showing how “belonging-being” (“perten-ser”) enhances participation/action (“particip-ação”). From these activities, we produced data revealing adolescents’ appreciation for experiences of community and solidarity experiences, the complexities and difficulties of social relationships among them, and the school as a space perceived as one of exclusion and non-belonging, while also providing adolescents’ suggestions to transform this school reality. Discussion: Initially, I propose a reflection that highlights the sense of belonging as an analytical key to understanding adolescent participation. Then, I emphasize that “belonging-being” seems to be related to the strengthening of bonds, connecting to concrete possibilities of access and rights guarantees. I also discuss belonging in light of social markers and intersectionalities, emphasizing that “belonging-being” in contexts of social inequality and exposure to different forms of prejudice and violence constitutes an act of resistance. Finally, I address my role as a researcher and occupational therapist, reflecting on the contributions of the field to conducting participatory research.