Engenharia Elétrica

URI Permanente desta comunidade

http://repositorio.ufes.br/handle/10/17617
Programa de Pós-Graduação em Engenharia Elétrica

Centro: CT
Telefone: (27) 4009 2663
URL do programa: https://engenhariaeletrica.ufes.br/pt-br/pos-graduacao/PPGEE

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Navegando Engenharia Elétrica por Autor "1º membro da banca"

Agora exibindo 1 - 6 de 6
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    Identificação e monitoramento de dormentes de ferrovias usando processamento de imagens
    (Universidade Federal do Espírito Santo, 2017-05-29) Franca, André Stanzani; Vassallo, Raquel Frizera; 1º membro da banca
    The railway is an important engine of the world economy. This means of transport more than 200 years old is efficient, safe and of great capacity and speed but still suffers from the difficulties of maintenance, mainly due to its assets of great extent, quantity, weight and geographic dispersion. In view of this, some initiatives in automatic inspection of railway assets have been developing. In particular, the inspection of railway sleepers (railway ties), which is sometimes done manually, needs development and consolidation. This dissertation presents a method for inventorying, identifying the type and some defects in sleepers based on image processing, heuristics and feature fusion in an unsupervised way. It uses Haar transform and integral images, as well as other image processing techniques such as edge detection and entropy computation along with aspects of railroad topology to achieve the proposed objectives. The algorithm was developed using real images of daily railway, previously unclassified, and that were subject to various noises and variations of a real railway operation. The method was validated through experiments with an image set that have approximately 33,000 sleepers. The results are promising and reach 97% accuracy in identifying the type of sleepers and reach 93% accuracy in identifying visible defects in sleepers.
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    Interface cérebro-computador baseada em potenciais evocados visuais em regime permanente para comando de uma cadeira de rodas robótica
    (Universidade Federal do Espírito Santo, 2012-08-01) Müller, Sandra Mara Torres; Sarcinelli Filho, Mário; Bastos Filho, Teodiano Freire; 1º membro da banca
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    Projeto de Topologias Virtuais para Redes Opticas Multiserviço
    (Universidade Federal do Espírito Santo, 2005-08-05) Almeida, Renato Tannure Rotta de; Calmon, Luiz de Calazans; 1º membro da banca
    Optical communication systems have emerged as the best solution for large scale data transport network implementation, providing optical channels with very high bit rates and covering large distances with low error probability. The entire bandwidth of the optical fibers became available with the development of the wavelength division multiplexing (WDM) technology, which allows several channels of different wavelengths to share the same physical links. The increase in physical link capacity was not the only benefit of WDM. The development of WDM optical devices, e.g., optical switches, multiplexers, demultiplexers, and tunable devices, has allowed the implementation of wavelength-routed optical networks. In such networks, the optical channels, also called lightpaths, are not restricted to the physical link edges. Wavelength routing detaches the lightpath configuration, or virtual topology, from the physical topology, permitting lightpaths to optically bypass intermediate nodes, until it reaches the destination node. In this Thesis we propose a Mixed-Integer Linear Programming (MILP) formulation to design virtual topologies in wavelength-routed optical networks, considering as objective function the minimization of the traffic forwarded electronically at the network nodes. Our goal is twofold. Firstly, to reduce processing requirements of the electronic routers, and secondly, to get the most transparent traffic distribution for a given traffic matrix, using the available optical resources at the nodes. Traffic segregation in classes was also included in the formulation, allowing differentiated routing criteria to each class. The proposed formulation was applied successfully to reasonable sized networks yielding optimal solutions in few minutes. To the best knowledge of the authors, this is the first report of a large MILP formulation that optimizes virtual topology and traffic routing of optical networks with low computational cost.
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    Projeto fuse sensor para melhora da qualidade da continuidade de energia elétrica a partir da diminuição do indicador DEC
    (Universidade Federal do Espírito Santo, 2024-05-27) Prazeres, Helder Batista de Boa Esperança dos; Co-orientador1; Orientador1; https://orcid.org/; http://lattes.cnpq.br/; 1º membro da banca; 2º membro da banca; 3º membro da banca
    The electrical power distribution systems play a crucial role in social well-being and economic development, providing the foundation for essential services and business sus tainability. However, many components of these systems face technological obsolescence, contributing to power supply failures at critical moments. This situation is further exacer bated in Brazil due to the predominance of bare conductors in its distribution networks and the limited presence of underground networks, making them susceptible to failures caused by external factors. It is observed, however, that these failures in the electrical system can take time to be detected and located, leading to a deterioration in power quality, specifically in the system interruption time, which increases the financial compensation paid by utilities to consumers. To address these challenges, this dissertation presents the Fuse Sensor project, developed in partnership with the company SEVEN (Seven Science Systems Ltda), as an innovative solution incorporating the concepts of Smart Grids and IoT (Internet of Things) technology for the faster location and repair of faults, thus enabling improvements in the efficiency and reliability of electrical systems. The Fuse Sensor is designed to meet the present and future needs of the electrical system, focusing on reducing the SAIDI (System Average Interruption Duration Index), and providing significant gains in compensations. The master’s project approach is structured into three distinct stages: in the first stage, the conception and construction of the Fuse Sensor project are presented, along with the testing procedures; in the second stage, validations of the Fuse Sensor project are conducted, including a comparison of the effectiveness of the communication technologies LoRa, SigFox, and FSK; and finally, in the third stage, an economic analysis is carried out, considering not only the acquisition costs of the innovative equipment but also its economic feasibility for the utilities. By addressing these aspects comprehensively, the Fuse Sensor project aims not only to mitigate the repair time of power supply interruptions but also to promote significant improvements in the quality and reliability of the electrical service. Combining technological innovation and detailed economic analysis, the project seeks not only to meet the current demands of the electrical sector but also to pave the way for a more efficient and sustainable future
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    Reator eletrônico microcontrolado de alto fator de potência para lâmpadas de alta intensidade de descarga
    (Universidade Federal do Espírito Santo, 2005-11-24) Orletti, Renato; Có, Márcio Almeida; Vieira, José Luiz Freitas; 1º membro da banca
    This work presents an overview about the High intensity discharge (HID) Lamps, showing its operation, the lamps variety and the peculiarities of this drive. The drive with electromagnetic ballast and electronic ballast are studied to verify advantages and disadvantages. After the analysis of electromagnetic and electronic drives, an electronic ballast is proposed. A prototype was implemented to verify the ballast performance. The experimental results have proved the viability of the electronic ballast proposed, emphasizing the reduced number of components used to make the prototype.
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    Uma Arquitetura para Ambientes Virtuaisde Conveniencia-Uma proposta Baseada emSistemas Multiagentes
    (Universidade Federal do Espírito Santo, 2006-09-29) Jose Francisco de Magalhaes Netto; Orientador1; 1º membro da banca
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