https://repositorio.unifei.edu.br/jspui/handle/123456789/481 2026-11-09T10:26:19Z https://repositorio.unifei.edu.br/jspui/handle/123456789/4325 Título: Proposta de sistemática para o processo de autoavaliação: uma contribuição para a avaliação e acompanhamento dos programas de pós-graduação profissionais Abstract: Brazilian graduate education is continuously seeking to refine its evaluation models to better assess its programs. In this context, self-evaluation (SE) stands out as a fundamental criterion for the continued accreditation of stricto sensu Postgraduate Programs, fostering internal improvements and alignment with the guidelines of the Coordination for the Improvement of Higher Education Personnel (CAPES). This work investigates SE practices in professional postgraduate programs (PGPs) within a Higher Education Institution (HEI), aiming to enhance these practices and align them with CAPES's expectations. Therefore, the objectives of this work consist of analyzing the context of Brazilian postgraduate education and the evaluation criteria pertaining to SE; describing and analyzing the SE practices in the HEI's professional PGPs and in a benchmark program; mapping documents and regulations regarding SE, establishing criteria for comparison and validation; and proposing improvements to the SE practices, based on the literature, CAPES guidelines, and best practices. The methodology, qualitative, exploratory, and descriptive, employs a multiple case study involving five PGPs from the HEI and a benchmark program. Document analysis encompasses legislation, CAPES regulations and guidelines, institutional documents, and public information from the Sucupira Platform. The results reveal heterogeneity in SE implementation, ranging from initial stages to more consolidated practices. Comparison with the benchmark program highlights the importance of aligning SE with strategic planning, stakeholder participation, consistent reporting and dissemination, and the use of results for continuous improvement. Furthermore, the study proposes an analytical framework with twelve items and characteristics for evaluating SE practices, categorized into four maturity stages. This research contributes to advancing knowledge about SE in PGPs by offering a methodology for analyzing and improving processes, thus strengthening self-evaluation in postgraduate education. Tipo: Dissertação 2025-07-01T00:00:00Z https://repositorio.unifei.edu.br/jspui/handle/123456789/4324 Título: Detecção de faltas de alta impedância em sistemas de distribuição utilizando transformada Wavelet e modelos de aprendizado de máquina Abstract: The identification of high-impedance faults is a recurring topic in the literature, given the importance of electric power in modern life and the disruptions caused by its absence. High-impedance faults are difficult to identify, presenting peculiarities and characteristics that can easily be mistaken for simple load variations in electrical systems. Conventional methods, such as those used in protection relays, may fail to correctly identify high impedance faults, delaying system restoration. The problems associated with delayed identification can have both economic impacts and pose safety risks to living beings. Therefore, considering the advancements in computational methods and their contribu tions to solving problems across various fields, the objective of this work is to apply these methods to the identification of high-impedance faults. To achieve this, machine learn ing algorithms were employed in combination with the Continuous Wavelet Transform (CWT) to analyze simulated electrical signals in IEEE 13-bus and 34-bus systems. The results showed improvements in the accuracy and precision of fault detection compared to existing methods in the literature, validating the effectiveness of the proposed approach. Tipo: Dissertação 2025-04-19T00:00:00Z https://repositorio.unifei.edu.br/jspui/handle/123456789/4323 Título: Análise e implementação de um algoritmo de sensação de movimento em uma plataforma de 2 graus de liberdade para treinamento de operadores de caminhões fora de estrada Abstract: Vehicle simulators in mining environments play an increasingly vital role in the development and training of operators, offering high safety, reliability, low cost, and the ability to create scenarios that would be difficult to reproduce under real conditions. However, due to spatial constraints, simulators cannot fully replicate the movements of real vehicles, especially off-highway trucks like the CAT793F, which exhibit distinct behaviors in acceleration, braking, turning, and other maneuvers. This work presents a methodology for implementing a washout-type Motion Cueing Algorithm (MCA) on a motion platform with two degrees of freedom (DoF), designed to simulate pitch and roll movements consistent with the operating conditions of mining trucks. The proposed algorithm was compared with an alternative approach and showed promising results, with better motion representation, lower response delay, and reduced system-induced noise. The evaluation of the results was conducted in three main stages: initially through an objective analysis using the OMCT (Objective Motion Cueing Test), followed by a comparison with the expected response of the human vestibular system, highlighting a good similarity, especially in the semicircular canals. Finally, the influences of noise and disturbances observed in the platform’s response were considered, with these deviations being strongly associated with dynamic effects resulting from the lack of anchoring of the base to the ground. This condition favors undesired displacements and imbalances during motion, directly affecting the accuracy of the simulation and the stability of the system. Tipo: Dissertação 2025-07-02T00:00:00Z https://repositorio.unifei.edu.br/jspui/handle/123456789/4319 Título: Análise das fases cristalinas na soldagem GTAW de aço inoxidável AISI 316L revestido por Níquel-Watts utilizando Thermo-Calc Abstract: This study investigates the microstructure and mechanical properties of the austenitic stainless steel AISI 316L after performing GTAW (TIG) welding using commercially pure argon gas (with 2% oxygen) at the ends of sheets that were previously subjected to nickel electrodeposition, containing a nickel-Watts solution enriched with niobium particulate (with a particle size of less than 150 µm) at room temperature. To evaluate the mechanical properties and microstructural changes, tensile tests, potentiodynamic polarization, Vickers microhardness, ferritoscopy, and microstructural analyses were conducted. The welding resulted in the formation of austenitic and delta ferrite (δ) phases, with a pronounced concentration in the molten zone (MZ), attributed to the rapid cooling characteristic of the welding process. Additionally, the emergence of metallic carbides and sigma (σ) phase was observed at grain boundaries, particularly in the heat-affected zone (HAZ). Ferritoscopy revealed a significant increase in the volumetric fraction of ferromagnetic phases in the welded regions, reaching 6.7% Fe in the MZ, 3.3% Fe in the HAZ, and 0.5% Fe in the base metal (BM). The microhardness results demonstrated differences among the analyzed regions, with the ZF exhibiting the highest microhardness value (231 HV ± 7 HV), followed by the ZTA with an intermediate value (188 HV ± 6 HV), and the base metal (BM) showing the lowest value (174 HV ± 1 HV). In the potentiodynamic polarization tests, the results indicated minimal variations in corrosion and pitting potentials between the base metal and the welded samples. For the welded sample, the average corrosion potential was measured at 0.02 V ± 0.01 V, with an average pitting potential of 0.24 V ± 0.01 V. Conversely, the base metal exhibited an average corrosion potential of 0.05 V ± 0.01 V and an average pitting potential of 0.29 V ± 0.01 V. Microfractographic analyses characterized the fracture of the welded samples as ductile, with the presence of dimples indicating a good capacity for deformation prior to rupture. Despite the addition of niobium to the nickel-Watts solution, the formation of niobium precipitates in the material was not identified, which may be attributed to the low thickness of the coating compared to the thickness of the weld bead, resulting in insignificant improvements in mechanical properties and corrosion resistance. Tipo: Dissertação 2025-02-20T00:00:00Z