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    Implementação e integração de uma arquitetura de software para um crawler de postagens em plataformas digitais
    (Universidade Federal de Goiás, 2024-12-19) Cesar, Lucas Rezende Soares; Brenner, Thor Franco; Barbosa, Jacson Rodrigues; Barbosa, Jacson Rodrigues; Oliveira, Marco Antonio Assfalk de; Graciano Neto, Valdemar Vicente
    The study addresses the issue of misinformation on social networks, a phenomenon exacerbated by artificial intelligence technologies and mass dissemination strategies, which undermine the credibility of democratic processes and the formation of public opinion. The research proposes a technical solution to automate the collection and analysis of data from fact-checking agencies and digital platforms, employing crawlers and APIs, with a focus on integration with the Web 3.0 Project. The results demonstrated the effectiveness of the developed architecture in consolidating structured data from reliable sources and social networks, enabling analyses such as sentiment analysis to identify polarizations and social trends. Despite limitations imposed by social network APIs, the system proved scalable and functional, contributing to a more agile and accessible fight against misinformation. Thus, the study highlights the importance of integrating technology and human expertise to tackle complex informational challenges.
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    Análise energética em uma instalação elétrica industrial
    (Universidade Federal de Goiás, 2024-12-05) Pacheco Junior, Paulo de Souza; Oliveira, Antônio Melo de; Belchior, Fernando Nunes; Belchior, Fernando Nunes; Mariano, Felipe Pamplona; Moreira, Leonardo de Queiroz
    This study investigates energy efficiency in an industrial electrical installation, focusing on power quality and optimizing the compressed air system, one of the largest energy consumers in industrial environments. The research explores practical and theoretically grounded measures to reduce energy consumption, enhance operational efficiency, and ensure the plant's sustainable growth—factors aligned with the United Nations' Sustainable Development Goals. Key approaches include reducing operating and cut-off pressure, recovering heat from compression, and controlling leaks. Efficiency analysis is conducted through methods such as plant consumption profiling, energy demand diagnostics, and calculating specific indicators like energy consumption per unit and system performance. Economic indicators, including Net Present Value (NPV), Internal Rate of Return (IRR), and simple payback period, were used to compassess the financial feasibility and savings potential of the proposed improvements. Additionally, the study highlights the energy-saving potential of recovering compression heat for preheating water used in other industrial processes, demonstrating reductions in both electricity consumption and boiler fuel costs. The results emphasize the strategic importance of energy efficiency for energy-intensive industries, showing that the applied measures contribute to more sustainable management and significantly reduce operational costs.
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    Análise do consumo de energia elétrica em grandes consumidores
    (Universidade Federal de Goiás, 2024-12-09) Reis, Amanda de Sousa Batista; Cruz, Daniel do Prado Mendes; Belchior, Fernando Nunes; Castro, Marcelo Stehling de; Castro, Marcelo Stehling de; Valle, Ana Cláudia Marques do; Belchior, Fernando Nunes
    This study analyzes the consumption profile of a Consumer Unit (CU) classified under Group A, supplied by Equatorial Goiás. The CU, part of the hotel industry, is characterized by high energy consumption, operates under the “Azul” tariff modality, and benefits from the Electric Power Compensation System (SCEE), which fully offsets its energy consumption. The analysis was conducted using Business Intelligence tools and methodologies for data processing, modeling, and visualization, supporting result interpretation and informed decision-making. The study examines current resolutions and tariff structures, as well as succinctly discusses the potential for leveraging the available data and information.
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    Diagnóstico de qualidade de energia elétrica em empresa com usina solar fotovoltaica
    (Universidade Federal de Goiás, 2024-12-05) Pimenta, Jader Fillipe Cabral; Belchior, Fernando Nunes; Belchior, Fernando Nunes; Santos, Josephy Dias; Oliveira, Antonio Melo de
    Electricity is an indispensable resource in modern society, essential for economic, social, and technological development. Its importance lies in sustaining the operation of basic infrastructure, such as hospitals, transportation, telecommunications, and supply systems, permeating all areas of daily life, from household activities to industrial processes. However, mere access to energy is not sufficient; the quality of supply is equally crucial. Parameters of Power Quality (PQ), such as voltage and frequency stability, harmonic control, and power factor, directly influence the reliability and efficiency of the supply. Non-compliance with these standards can result in power outages, equipment overloads, and damage, leading to economic losses and safety risks. Thus, maintaining high PQ is essential to prevent interruptions and ensure user well-being. In the industrial sector, the importance of PQ is even greater due to the complexity of production processes. High-quality electricity is critical for the efficient operation of precision equipment, automated systems, and production lines, as variations such as overvoltage’s, harmonic distortions, and frequency fluctuations can cause unexpected stoppages, shorten equipment lifespan, and increase maintenance costs. The electricity photovoltaic generation has been widely adopted in industrial facilities as a cost-reduction strategy and for being a more sustainable source in terms of environmental preservation. This practice aligns with the Sustainable Development Goals (SDGs) established by the United Nations (UN), particularly SDG 7, which aims to ensure universal access to affordable, reliable, sustainable, and modern energy. This study analyzed the relationship between this type of generation and the compliance with PQ parameters in an industrial facility. Concepts were addressed, and aspects such as steady-state voltage, power factor, harmonic distortions, frequency, voltage imbalance, and reverse power flow were evaluated. Real data collected over a week were graphically processed to illustrate the impacts of power injection from the plant on quality indicators. Compliance was assessed based on PRODIST standards.
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    Proposta de otimização do plano de manutenção de uma autoclave utilizada em ambientes hospitalares
    (Universidade Federal de Goiás, 2024-11-11) Pinto, Carlos Daniel Silva; Figueiredo, Kléber Mendes de; Figueiredo, Kléber Mendes de; Vilela, Carlos Alberto de Almeida; Colvero, Diogo Appel
    The study was motivated by the critical importance of sterilization performed by autoclaves for the proper and safe treatment of patients in hospital environments. It aimed to improve the maintenance plan for a Baumer HI VAC MX II B0112 autoclave used for sterilization in a hospital setting, classified as a Category V pressure vessel under NR 13. The methodology included an analysis of the maintenance history (2022–2023), identification of critical components, implementation of predictive maintenance techniques (non-destructive testing and visual inspection), optimization of the maintenance schedule, improvement in inventory management, and the implementation of a data recording and analysis system. The results showed an increase in maintenance performance indicators, with a 23.4% improvement in MTBF (Mean Time Between Failures), rising from 255.5 to 315.22 hours. Additionally, there was a 29% reduction in MTTR (Mean Time to Repair), decreasing from 18.65 to 13.25 hours, and an increase in equipment availability from 92.37% to 95.97%. Improvements included predictive maintenance, schedule optimization based on actual wear, integrated inventory management, and compliance with regulations such as RDC 15. Despite the short post-improvement analysis period (6 months), the project demonstrated potential to enhance operational efficiency, reduce costs, and improve safety. Continuous monitoring, full implementation of the proposed actions, and expansion of the predictive maintenance plan are recommended. The project contributed to the optimization of sterilization processes, positively impacting the quality of patient care and the safety of medical procedures.
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    Aplicação dos metamateriais acústicos na transmissão sonora
    (2024-12-18) Silva, Bruno Cordeiro e; Fagundes Neto, Marlipe Garcia; Fagundes Neto, Marlipe Garcia; Kitatani Junior, Sigeo; Rodrigues, Marcos Vinicius Silva
    Metamaterials are structures designed to exhibit physical properties not found in natural materials, such as controlled manipulation of sound waves, enhancing acoustic mitigation. When combined with additive manufacturing, this technology offers new possibilities for acoustic insulation. This study aims to explore the concept and application of the acoustic metamaterial model UOM (Ultra-open Metamaterial) proposed by Ghaffarivardavagh (2018), validating its efficiency in sound transmission loss based on its geometry. Additionally, the research investigates the advantages of simulations applied to acoustic silencers, evaluating their accuracy through impedance tube tests in conjunction with additive manufacturing of the silencer. The results indicate that the study's objectives were achieved, showing alignment between analytical, simulated, and tested results, with error margins ranging from 0.4% to 8.0%. The tests also showed proximity to the simulations, with a 3.5% error in the frequencies of maximum transmission loss, despite differences in peak absolute values. However, the fabrication of physical models using 3D resin printing revealed structural weaknesses due to reduced dimensions, highlighting challenges to be addressed for improved practical feasibility.
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    Deep learning para reconhecimento de sinais da LIBRAS como tecnologia assistiva
    (Universidade Federal de Goiás, 2024-12-12) Pedrosa, Samuel França da Costa; Santana, Adriano César; Santana, Adriano César; Castro, Marcelo Stehling de; Nerys, José Wilson Lima
    Communication is essential for social inclusion, yet the lack of linguistic accessibility often marginalizes specific groups, such as the Brazilian deaf community. This project proposes the use of deep learning to recognize signals from Brazilian Sign Language (LIBRAS) with the aim of translating them, through model predictions, into written Portuguese. Initially, videos of people signing were collected to form a dataset, which was subjected to processes of extraction and mapping of key body points using open-source tools provided by MediaPipe. The extracted data was processed and used as input for two designed models: one based on Long Short-Term Memory (LSTM) and another on Transformers. The study revealed that model performance is influenced by the alignment methods applied during data processing. The Transformer demonstrated superior results in terms of accuracy and generalization, albeit with higher computational demands. Conversely, the LSTM model showed satisfactory performance in terms of computational efficiency but exhibited limitations as classification complexity increased. One of the primary challenges was the difficulty in building a rich and robust dataset, due to the scarcity of available content for collection and extraction, especially when compared to other natural languages, whether textual or spoken. This limitation partially restricted the models' generalization capabilities. Despite these challenges, the project achieved promising results, suggesting that with enhanced and expanded datasets, its application as assistive technology can be extended to more complex scenarios with broader applicability. This study represents an advancement in the use of deep learning to promote inclusion and accessibility for the Brazilian deaf community.
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    Representação simplificada de um alimentador de média tensão da região metropolitana de Goiânia
    (Universidade Federal de Goiás, 2024-12-12) Nascimento, Guilherme Pereira do; Lima, Ian Douglas Jacob de; Kopcak, Igor; Kopcak, Igor; Brigatto, Gelson Antônio Andrêa; Garces Negrete, Lina Paola
    Studies on electric power systems, given its physical dimensions and power ratings, as well as its economic and social relevance, are typically conducted through computational simulations based on mathematical models of electrical grids, generators, loads, substations, and other components. The limitations regarding “bench testing” and even field testing create a demand for test systems that represent real networks for computational simulations, which can support various types of analysis. In this regard, benchmark test systems have historically been used as reference models. Depending on the objective or phenomenon to be analyzed, there are specific reduced test systems whose mathematical models are more appropriate for focusing on studies related to operational planning, system stability, and network protection security, among other possibilities. This paper develops a reduced equivalent of an electrical grid that serves the metropolitan area of Goiânia, based on data available in the literature as well as data requested from the local utility company, and it is representative of the dynamic behavior of this small portion of the National Interconnected System (SIN).
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    Avaliação da sobreamostragem de dados de voz na classificação automática da doença de Parkinson
    (Universidade Federal de Goiás, 2024-12-19) Silva, Matheus Isac da; Felix, Juliana Paula; Felix, Juliana Paula; Silva, Karina Rocha Gomes da; Salvini, Rogerio Lopes
    This study investigates a possible bias in oversampling via data windowing of vocal signals. Previous studies indicate that there is a bias for gait data when the data is treated independently, in addition there are statistical studies that show that data from the same individual carry similar information. An approach based on three databases containing vocal signals was used, two of which were unbalanced and one balanced. The K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Linear Discriminant Analysis (LDA), Naive Bayes and Decision Tree (DT) algorithms were applied, with pre-processing using StandardScaler and PCA behavior analysis. Cross validation was done with k-fold Cross Validation, with k=5, in all 3 bases, adapted for scenarios with and without bias in the training data. Models evaluated without considering bias showed inflated performances, while the rigorous approach showed more modest results. It is concluded that samples from the same individual in training and testing can inflate the performance of models, and it is crucial to apply oversampling correctly to develop reliable models for diagnosing PD.
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    Desenvolvimento de uma plataforma para o gerenciamento de anomalias em usinas
    (Universidade Federal de Goiás, 2024-12-09) Barros, Arthur Faggin; Castro, Marcelo Stehling de; Castro, Marcelo Stehling de; Valle, Ana Cláudia Marques do; Belchior, Fernando Nunes
    This work presents the development of a maintenance management portal focused on automating the registration, scheduling, and analysis of corrective and preventive maintenance. The system was developed using Python with Flask, along with HTML, CSS, JavaScript, and MariaDB for data storage. Key features include anomaly reporting, creating preventive maintenance plans, scheduling maintenance, and data visualization through dashboards. The implementation of the system automated processes previously performed manually, such as sending preventive maintenance alerts and scheduling interventions. Usability and integration tests were conducted to validate the portal's functionality, and the results indicated a significant improvement in operational efficiency and asset management. Additionally, the system proved to be an effective tool for maintenance data analysis, providing reports and indicators that support decision-making. Finally, the system contributed to reducing operational costs and increasing asset availability, highlighting the importance of digitization in maintenance management.
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    Solução automática do cubo de Rubik usando visão computacional
    (Universidade Federal de Goiás, 2024-12-12) Lima, Gustavo Vinícius Taveira; Santana, Adriano César; Santana, Adriano César; Nerys, José Wilson Lima; Castro, Marcelo Stehling de
    The present work aims to develop an automated system to solve the Rubik’s Cube using computer vision. To execute this project, preliminary theoretical research was conducted, followed by the acquisition of the necessary components and the assembly of the prototype, which uses the Arduino Uno and ESP32-CAM microcontrollers. The computer vision algorithm was implemented in Python, using the OpenCV library, while the microcontroller programming was carried out in C++. To solve the cube, the Kociemba algorithm was adopted. The developed system is capable of automatically recognizing the colors of the cube’s faces and executing the necessary moves to solve it, achieving an efficient solution, with a resolution time of approximately four minutes, in addition to offering an intuitive and easy-to-use interface.
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    Implantação de estação base 5G de baixo custo
    (Universidade Federal de Goiás, 2024-12-11) Gomes, Giulia Ferreira; Silva, Ytalo Breno Barbara; Rocha, Flávio Geraldo Coelho; Rocha, Flávio Geraldo Coelho; Castro, Marcelo Stehling de; Lemos, Rodrigo Pinto
    This work presents the deployment of a 5G network designed for Small and Medium-sized Enterprises (SMEs) using low-cost equipment, including a Raspberry Pi 5 and a self-assembled desktop, along with open-source software serving as the Radio Access Network (RAN) and Core Network (CN). To achieve this, the research addresses the understanding of the architecture of fifth-generation (5G) networks, the licensing requirements for the use of networks and the radiofrequency spectrum in Brazil under the regulation of the National Telecommunications Agency (ANATEL), and an overview of the functionality of software-defined 5G network components. The software solutions were selected based on an analysis of their licensing for commercial use, specifically focusing on srsRAN Project and Open5GS. Two network prototypes are presented: one with the RAN and CN integrated on a Raspberry Pi 5, and another with the RAN and CN decoupled, deployed on the desktop and Raspberry Pi 5, respectively, connected via an Ethernet interface. Despite the limited results, the developed prototypes represent a first step toward refining solutions aimed at serving SMEs using accessible hardware and open-source software.
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    Análise do funcionamento das funções 51, 27, 59 e 87 em diversas condições de curto-circuito de uma linha de transmissão de alta tensão utilizando o software ATPDraw
    (Universidade Federal de Goiás, 2024-12-12) Souza, Alex de Almeida Rodrigues de; Campos, Laura Ferreira; Almeida, Maria Leonor Silva de; Almeida, Maria Leonor Silva de; Kopcak, Igor; Belchior, Fernando Nunes
    The present study investigates, through the implementation in the ATPDraw software, the behavior of four functions commonly used in the protection of high-voltage transmission lines: overcurrent (51), overvoltage (59), undervoltage (27), and differential (87) functions. ATPDraw, a program used for simulating electromagnetic transients in power systems, servesas a tool to study the behavior of these protection functions under different fault scenarios. It offers a practical and detailed approach, enabling the modeling of transient behavior in electrical systems and the evaluation of how different protection strategies can mitigate interruption risks, contributing to a safer and more reliable electrical grid. The results revealed that the performance of protection functions is strongly influenced by operating conditions, such as the type of short circuit (monophase or three-phase), fault resistance, and fault location. While functions like 87 proved to be highly effective and consistent across all tested scenarios, current- or voltage-based functions such as 51, 27, and 59 exhibited variations under specific conditions, such as high fault resistance or fault locations. These findings highlight the importance of precise adjustments and the integration of diverse protection strategies to maximize system reliability and safety. The research concludes that simulation tools like ATPDraw are essential for validating protection settings and enhancing the performance of complex electrical systems.
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    Avaliação da confiabilidade em sistemas de distribuição de energia elétrica com alta inserção de geração distribuída: uma abordagem através do método de Newton-Raphson e da simulação de Monte Carlo
    (Universidade Federal de Goiás, 2024-12-11) Sabreu , Igor Lyncoln da Silva; Garces Negrete, Lina Paola; Garces Negrete, Lina Paola; Brigatto, Gelson Antônio Andréa; Belchior, Fernando Nunes
    This study aimed to evaluate the influence of distributed generation (DG) on reliability parameters in electrical distribution systems, analyzing such metrics before and after allocation. In a different way, this work adopts the integration of the Monte Carlo technique with the Newton-Raphson method, applied to the resolution of the power flow problem, incorporating islanding detection based on Graph Theory. In addition, the use of the goodness-of-fit test (adherence) allows validating the adequacy of probabilistic distribution functions to stochastic variables, ensuring a diagnosis that is more faithful to real behavior. The analyzes were performed using the 14-bus RBTS test system. To this end, five indices were chosen to assess grid reliability: LOLE (Loss Of Load Expectation), LOEE (Loss OF Energy Expectation), FEC (Frequency of Exceeding Capacity), IEC (Interrupted Energy Consumption) and IVR (Interruption Value Rate) , which together provide an excellent perspective of the system. With the addition of decentralized generation, an increase in system availability was noted, a decrease in voltage deviations in the grid, a reduction in unserved energy and fewer occurrences of failures. Thus, the integration of decentralized generation not only improves the parameters evaluated, but also highlights the points in the network that require greater care and allocation of resources, whether in protection devices and systems or in predictive maintenance actions, preventing possible technical complications and excessively high corrective expenses, following the objectives and guidelines of SDG 7 (Sustainable Development Goals), proposed by the UN (United Nations), which aims at clean and affordable energy.
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    Desafios para a comercialização internacional de energia elétrica brasileira
    (Universidade Federal de Goiás, 2024-12-12) Oliveira, Gabriel Souza de; Santana, Lucas Souza de; Garces Negrete, Lina Paola; Garces Negrete, Lina Paola; Kopcak, Igor; Mello, Igoor Morro
    By analyzing the size of Brazil’s electricity potential, which has highly favorable geographical conditions for renewable generation, we can see how beneficial the international energy trading process is, not only from an economic point of view, but mainly in terms of contributing to a global electricity matrix with a greater share of renewable sources. It is therefore important to study how the current commercial process of electricity exchange works and what the challenges are in building a more favorable scenario in this regard. This reflection is the result of understanding how positive this process of international energy trading is, which also brings greater energy security to the participating countries, and it is therefore necessary to understand the current context, with a view to proposing the challenges observed in this area.
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    Análise da inversão do fluxo de potência em instalação elétrica industrial com geração de energia solar fotovoltaica
    (Universidade Federal de Goiás, 2024-12-03) Ferreira, Gabriel Fernandes; Belchior, Fernando Nunes; Belchior, Fernando Nunes; Oliveira, Antônio Melo de; Castro, Marcelo Stehling de; Pires Junior, Kairo Hitler De Almeida Faria
    The increasing integration of distributed generation, particularly solar photovoltaic energy, in industrial installations has revealed critical challenges for the stability and quality of electrical systems. Phenomena such as power flow inversion, harmonic distortions, current and voltage imbalances, and power factor variations add complexity to electrical operations, demanding advanced monitoring and control techniques. These challenges are further exacerbated in industrial contexts, where energy demand is highly dynamic and subject to abrupt changes, intensifying the interactions between local generation and the electrical grid. Such dynamics can significantly impact system reliability, compromising equipment efficiency, reducing lifespan, and increasing operational costs. Moreover, energy quality distortions can cause premature wear of critical components, transformer overloads, and disruptions to plant operations, directly affecting productivity. These consequences highlight the need for solutions that align electrical operations with regulatory compliance, ensuring system stability and efficiency. The main motivation for this study emerged from an incident reported by the maintenance team at Volga Engenharia, where an overload in the entry transformer tripped its protections, disconnecting it from the system and preventing catastrophic equipment failure. This critical event highlighted the need to deeply understand the phenomena associated with distributed generation, particularly power flow inversion and its impacts on the electrical system. In this context, the opportunity arose to align this academic research project with the challenges faced by the company, focusing on practical and technical solutions. Throughout the development of this work, the scope of the analysis expanded to address additional issues related to energy quality and specific operational conditions of the plant. Data obtained during monitoring provided a detailed view of the effects of abrupt power flow inversion and its implications on other critical parameters, such as current imbalances and harmonic distortions. This analysis reinforces the importance of studies like this one, aiming not only to understand the challenges posed by distributed generation but also to propose solutions that ensure efficiency, safety, and sustainability for industrial systems.
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    Modelagem de uma rede de distribuição real no software ATPDraw e análise dos impactos da conexão de geração distribuída ao sistema
    (Universidade Federal de Goiás, 2024-12-13) Gomes, Caio Santos; Lima, Yuri Gonçalves; Kopcak, Igor; Kopcak, Igor; Almeida, Maria Leonor Silva de; Brigatto, Gelson Antônio Andréa
    This study analyzes a distribution network of the Equatorial Goiás system, evaluating the influence of Distributed Generation (DG) on protection systems. The main focus is the modeling of a real primary feeder in the ATP environment, combined with the application of protection functions required by PRODIST (Procedures for Distribution of Electrical Energy in the National Electrical System) and previously modeled. The studyvalidates these functions under disturbance scenarios, verifying the reliability of the protections and their impact on the system, thus highlighting the importance of aspects such as selectivity, speed, sensitivity, and reliability, which are essential to ensuring the proper operation of the distribution system. The research investigates the impacts of DG on a medium-voltage distribution network, based on the technical requirements of PRODIST, addressing planning aspects and necessary adjustments for the efficient integration of this technology. Furthermore, the study examines changes in voltage and current profiles in the network before and after the connection of DG, as well as the effects of simulated short circuits at different points of the primary feeder. The results demonstrate the differences between short circuits occurring near and farther from the DG connection point and illustrate the operation of PRODIST functions. The importance of the precise operation of each function is emphasized to ensure system efficiency and adequate device protection. The study underscores the importance of thorough planning, including power flow and transient stability studies, to ensure the efficient integration of DG. Finally, it concludes that the modeling of the distribution system in the ATP environment was coherent and accurate.
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    Análise de faturamento para consumidores do grupo A: estudos de caso e propostas de otimização
    (Universidade Federal de Goiás, 2024-11-12) Correia, Matheus Vicente; Belchior, Fernando Nunes; Belchior, Fernando Nunes; Oliveira, Antônio Melo de; Castro, Marcelo Stehling de; Santos, Josephy Dias
    This study presents a detailed analysis of billing for Group A consumers, focusing on case studies and optimization proposals. The research addresses the current tariff models in Brazil and their application in calculating electricity consumption and demand, considering the importance of the electricity bill history as an analysis tool. Additionally, concepts such as power factor and the use of capacitor banks for reactive power correction are explored, aiming at reducing penalties and improving energy efficiency. Based on case studies, solutions are proposed for optimizing consumption and contracted demand of the analyzed consumer units to promote cost reduction and improve energy management. It concludes that adopting best practices in demand sizing and efficient use of reactive energy can result in financial benefits for both energy distributors and consumers. This work contributes to SDG 7 – Affordable and Clean Energy by promoting energy efficiency practices and consumption optimization, which aim at both cost reduction and the conscious use of electricity, positively impacting the sector's sustainability and fostering the development of solutions that minimize the waste of natural resources.
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    Sistema de inspeção visual para detecção de sarna em folhas de macieiras
    (Universidade Federal de Goiás, 2024-12-19) Sobreira, Lucas Duarte; Saleh, Tarek Campos; Vinhal , Cássio Dener Noronha; Vinhal , Cássio Dener Noronha; Oliveira, Marco Antônio Assfalk de; Cruz Júnior, Gelson da
    Apple scab, caused by the fungus Venturia inaequalis, poses a substantial threat to apple production, particularly for small-scale farmers in resource-constrained environments. Traditional visual inspection methods are often ineffective, necessitate technical expertise, and are impractical on a large scale. This work proposes an economical and offline-capable solution for detecting apple scab, employing lightweight Convolutional Neural Networks (CNNs) and an intuitive web application. Images were collected from three datasets—ATLDSD, eScab, and AppleScabLDs—and class imbalance was mitigated through data augmentation. Various models were evaluated, including MobileNet V3, ShuffleNet V2, and RegNet, with ShuffleNet V2 achieving the highest accuracy (92.83%). The system integrates a web application based on Next.js and React.js, hosted on Vercel, with local inference utilizing ONNXRuntime-web and Jimp for image preprocessing. This solution provides farmers with an accessible, efficient, and offline diagnostic tool, contributing to enhanced agricultural productivity and improved disease management.
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    Envelhecimento de características da voz
    (2024-12-19) Silva, Matheus Carlos Lima e; Pinheiro Júnior, Carlos Galvão; Pinheiro Júnior, Carlos Galvão; Cardoso, Alisson Assis; Gris, Lucas Rafael Stefanel
    This work presents an approach based on linear models to recover the vocal identity of individuals with dysphonia, using recordings made before the onset of the disorder. The method applies transformations aimed at approximating the representation of vocal age to what the individual would have had if the disorder had not compromised voice quality. The classification models achieved a mean absolute error of 3.49 years in age prediction, although the analysis was limited by an imbalanced dataset with low representativeness across different age groups. Furthermore, a simple linear model applied to speaker embeddings showed promising performance within the scope of the available data. Despite the demonstrated potential, further validation with larger and more diverse datasets is needed to ensure its practical applicability and adaptation to individual particularities.