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Desenvolvimento de um sistema de aquecimento por radiação com lâmpadas infravermelhas para utilização em manufatura aditiva
(Universidade Federal de São Carlos, 2025-04-24) Govoni, Valter Cesar; Malavolta, Alexandre Tácito; https://lattes.cnpq.br/8477313173581967; https://lattes.cnpq.br/8111798381904307
In the modern manufacturing process research for new materials and different manufacturing methods has intensified with the purpose of increasing production, quality and easy of assembly of parts more complex. One of these technologies is 3D Printing, also known as Manufacturing Additive, which began to emerge in the 1980s with the purpose of producing prototypes three- dimensional, and currently joined in the final manufacture of products through the physical creation of a three-dimensional digital model depositing successive layers of material, until obtaining the finished piece. Despite already although there are several types of 3D printing, they are all based on the same principle of deposition by layers, but is constantly modernizing, only the material deposited varies. In this context, the present research aims to investigate the effect of temperature on the mechanical strenght and surface quality characteristics of parts printed using the FPM (Fused Pellet Modeling) technique, using the ABS (acrylonitrile butadiene styrene) polymer. To this end, a still unusual low-cost complementary heating system was developed using infrared lamps integrated into a large-scale 3D printing manufacturing cell. The main objective is to verify how additional temperature can inprove the mechanical resistance and surface quality of large-volume parts produced. Also, as the part is being built, sensors read the temperature of the part in real time, and via wireless connection, the values of these measured temperatures are sent to a data recorder, which is a computer mounted remotely near the manufacturing cell, where they can be analyzed in real time or later, in the form of tables or graphs.
Resolução de problemas de matemática da Olimpíada Brasileira de Matemática das Escolas Públicas sob a visão da metodologia de Polya
(Universidade Federal de São Carlos, 2025-04-24) Batista, Ailton Cecílio; Seixas, Wladimir; https://lattes.cnpq.br/1697352974728327; https://orcid.org/0000-0002-0843-3500; https://lattes.cnpq.br/4397355751940879; https://orcid.org/0000-0002-5168-0320
The objective of this work is to use Pólya’s problem-solving methodology as a tool for teaching and learning geometry concepts in the classroom. The study was developed based on four exercises from the question bank of the Brazilian Mathematics Olympiad for Public Schools (OBMEP), addressing topics such as perimeter, area, and formation rules. In addition to analyzing Pólya’s methodology, a generalization of the worked-out problems was made, which constitutes one of the main objectives of the book How to Solve It. This entire process was conducted in alignment with the skills and competencies outlined by the National Common Curricular Base (BNCC).
Impactos das Mudanças no Uso e Cobertura do Solo na Produção e Exportação de Sedimentos na Bacia Hidrográfica do Alto Paranapanema
(Universidade Federal de São Carlos, 2025-04-24) Boniolo, Vinicius Rainer; Martensen, Alexandre Camargo; https://lattes.cnpq.br/1608659358382981; Mello, Kaline de; https://lattes.cnpq.br/1974531968891537; https://lattes.cnpq.br/8757447264574231
Changes in land use and land cover are important drivers of environmental degradation in watershed areas, intensifying erosive processes and compromising the provision of ecosystem services that regulate water quantity and quality. This dissertation aimed to assess the impacts of such changes on sediment production and export in the Upper Paranapanema River Basin (BH-ALPA), located in the state of São Paulo, through multitemporal modeling based on four decades (1987, 1997, 2007, and 2017), spatial pattern analysis associated with different land use types, simulation of scenarios involving the restoration of Permanent Preservation Areas (APPs) and soil conservation practices, and validation of the modeled data with direct field measurements. The work was structured into three integrated chapters: a theoretical review, multitemporal modeling, and an applied evaluation in micro-watersheds with different land use matrices. Chapter 1 consisted of a literature review aimed at understanding the relationships between land use, erosive processes, and environmental management strategies in watersheds. This review discussed the main natural and anthropogenic factors driving soil degradation, with emphasis on the role of vegetation in controlling erosion. It also presented a critical analysis of the main models used to estimate erosion and sediment transport in watersheds, including empirical models (such as RUSLE) and semi-empirical/semi-distributed models (such as MUSLE, SWAT, AnnAGNPS, and SDR-InVEST), justifying the adoption of the SDR-InVEST model in this research. In Chapter 2, the model was applied to estimate sediment production and export in BH-ALPA for the years 1987, 1997, 2007, and 2017, based on land use data from the MapBiomas platform. The results indicated a significant increase in sediment export over recent decades, associated with the intensification and conversion of landscapes for agriculture. The modeling also made it possible to test scenarios of APP restoration and the implementation of conservation practices. Chapter 3 deepened the analysis of the influence of land use and land cover on water quality in four sub-watersheds with different landscape matrices: agriculture, pasture, and forest. Flow and physicochemical parameters of the water were collected over seven sampling campaigns and analyzed through descriptive, correlational, and multivariate statistical methods. The results revealed distinct patterns among land use types, with greater stability in forested areas and higher variability in intensively managed agricultural landscapes. Overall, the research highlights the importance of integrating soil conservation strategies into territorial planning in watersheds. Conservation practices, restoration of degraded areas, and the protection of APPs are shown to be essential for reducing sediment export and ensuring the maintenance of ecosystem services.
Abordagens para reagendamento de voos de helicópteros em uma empresa de óleo e gás natural
(Universidade Federal de São Carlos, 2025-04-24) Fantazzini, Tarley Mansur; Munari Junior, Pedro Augusto; https://lattes.cnpq.br/1328868140869976; https://orcid.org/0000-0001-5929-593X; Morabito Neto, Reinaldo; https://lattes.cnpq.br/4194801952934254; https://orcid.org/0000-0002-3948-305X; https://lattes.cnpq.br/8785320051083372; https://orcid.org/0009-0005-4334-7770
Air transportation of passengers relies on prior planning of scheduled flights. However, unforeseen events may affect this scheduling, making recovery and rescheduling actions necessary. In this context, the Aircraft Recovery Problem (ARP) arises, aiming to reschedule flights affected by such disruptions. This work addresses a specific ARP faced by a Brazilian oil and natural gas extraction company operating offshore platforms, where third-party helicopters are used to transport employees between airports and maritime units. Several optimization-based approaches are proposed to model and solve this problem. Initially, hierarchical goal programming was applied with three sequential objectives: minimizing the number of postponed flights, helicopter usage, and total delays. Optimal or near-optimal solutions were obtained with low computational times for instances with up to 50 flights. Subsequently, multi-objective models were adopted, including the weighted Chebyshev metric and the approach proposed by Lokman and Köksalan, enabling the identification of non-dominated solutions that compose the Pareto frontier. These methods showed promising results, with computational gaps below 12% and reduced execution times, even with a shortened time limit. To complement the deterministic approaches, stochastic programming techniques were incorporated to handle uncertainties in the problem parameters, aiming to capture and analyze the variability and risks associated with uncertain values such as flight time between the airport and maritime units. The integration of deterministic and stochastic approaches provided a comprehensive and flexible analysis of this ARP, enabling result optimization in both controlled and uncertain scenarios, and contributing to more effective management of aircraft recovery operations.