Ronaldo De Freitas Zampolo

Ronaldo De Freitas Zampolo
Federal University of Pará | UFPA · Department of Computer and Telecommunications Engineering

Ph.D.

About

43
Publications
13,207
Reads
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74
Citations
Citations since 2016
17 Research Items
32 Citations
201620172018201920202021202202468
201620172018201920202021202202468
201620172018201920202021202202468
201620172018201920202021202202468
Introduction
Ronaldo F Zampolo is with the Signal Processing Laboratory (LaPS) at the Federal University of Pará (UFPA). His current research interests include eye-tracking systems, visual attention models, visual quality assessment, and human activity recognition.
Education
March 1998 - June 2003
Federal University of Santa Catarina
Field of study
  • Electrical engineering
March 1996 - March 1998
Federal University of Santa Catarina
Field of study
  • Electrical engineering
March 1990 - September 1995
Federal University of Pará
Field of study
  • Electrical engineering

Publications

Publications (43)
Article
Full-text available
A Internet das Coisas (Internet of Things - IoT) é um paradigma bem conhecido que define um ambiente dinâmico e inter-relacionado de dispositivos de computação com diferentes componentes para uma conectividade perfeita e transferência de dados. O campo da tecnologia vestível é um dos mais populares nos dias de hoje e prevê-se que continue em expans...
Conference Paper
Full-text available
Resumo-Alvo de diversas pesquisas, a estimação de posicio-namento de cabeça tem por objetivo determinar a posição de um indivíduo em uma determinada cena. Estratégias de análise de vídeo para estimação de posição de cabeça que funcionem com webcams convencionais têm um papel central em sistemas de rastreamento ocular de baixo-custo. Neste trabalho,...
Conference Paper
Full-text available
Considerando o volume de dados produzidos diariamente por centros medico-hospitalares, algoritmos de compressão para imagens médicas representam uma alternativa para reduzir custos de transmissão e armazenamento em sistemas PACS. Nesse caso, esquemas adaptativos podem maximizar a compressão evitando a perda de qualidade visual e, por conseguinte, o...
Conference Paper
Full-text available
The inspection of train and railway components that can cause derailment plays a key role in rail maintenance. To improve productivity and safety, service providers look for automatic and reliable inspection solutions. Although automatic inspection based on computer vision is a standard concept, such an application challenges development community...
Conference Paper
Full-text available
The prediction of visual quality is crucial in image and video systems. Image quality metrics based on the mean square error prevail in the field, due to their mathematical straightforwardness, even though they do not correlate well with the visual human perception. Latest achievements in the area support that the use of convolutional neural networ...
Conference Paper
Full-text available
As atividades de extensão são reconhecidas como essenciais para que a universidade atinja seus propósitos, promovendo a integração entre o conhecimento produzido na academia e as demandas/desafios sociais. Apesar do conhecido princípio de indissociabilidade entre Ensino, Pesquisa e Extensão, em muitas situações tais elementos encontram-se desarticu...
Conference Paper
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Para melhorar a experiência em sala de aula, aumentar a motivação dos discentes, bem como combater as taxas de retenção e evasão, educadores em engenharia vêm adotando estratégias metodológicas não tradicionais, a fim de promover o desenvolvimento de competências mais alinhadas com as necessidades do mercado. Diante disso, temos como objetivo desse...
Conference Paper
Full-text available
Resumo: Motivar alunos de engenharia na maioria das vezes é um desafio. A gamificação pode ser utilizada para propiciar essa motivação. O objetivo deste documento é relatar a experiência de utilização de estratégias de games (gamificação) na disciplina Processamento Digital de Sinais, nos cursos de Engenharia da Computação e Engenharia de Telecomun...
Conference Paper
Full-text available
Compression in medical images has the potential to reduce costs in data transmission and storage in Picture Archiving and Communications Systems (PACS). In this case, the availability of adaptive schemes for codec tuning would be worthwhile for maximising compression and, at the same time, avoiding quality loss, considering the diagnostic value of...
Conference Paper
Full-text available
Several applications (crowdsourcing, human-computer interface, and web design, just to name a few) can largely benefit from reliable low-cost eye/gaze tracking solutions with either reduced or no-calibration procedure. Although very accurate eye/gaze trackers are currently affordable to common users, special hardware is still needed and calibration...
Article
Full-text available
Partial discharge (PD) monitoring is widely used in rotating machines to evaluate the condition of stator winding insulation, but its practice on a large scale requires the development of intelligent systems that automatically process these measurement data. In this paper, it is proposed a methodology of automatic PD classification in hydro-generat...
Conference Paper
Full-text available
Visual quality metrics make easier the optimisation of image processing systems, when comparing with the case when only subjective assessments are taken into account. However, as important as having such metrics available is being able to assess and compare their performances. In this work, we present an application conceived to easily assess the p...
Conference Paper
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Current availability of image editing software with high levels of quality and continuously decreasing cost has been motivating the development of automatic techniques for detecting digital image forgeries. In this paper, we propose a decision strategy based on SLNF-ELM classifiers for a forgery detector that considers the integrity of CFA interpol...
Conference Paper
Full-text available
Seeking to improve the security in daily life, locks are used as a way to ensure private property. Common locks are flawed by not identifying the users who unlock them. This paper proposes a solution in the form of an electric lock activated by facial recognition based on eigenfaces and OpenCV. The processing is performed on a smartphone that commu...
Article
Full-text available
In order to measure electrical signals produced by partial discharges in hydrogenerators stator windings, capacitive couplers are regularly used. They are electrically connected to the windings and therefore, require undesired insulation intrusion. For avoiding such an intrusion, a microstrip directional coupler is used, which is experimentally and...
Conference Paper
Full-text available
Este artigo apresenta uma técnica para seleção de sub-bandas wavelet como etapa preliminar de um sistema de monitoramento e análise de descargas parciais. Tal seleção é realizada de maneira automática, mediante o uso de um classificador baseado em rede neural artificial do tipo SLFN (single hidden layer feedforward network) com algoritmo de aprendi...
Conference Paper
Full-text available
In this paper, the problem of device identification based on sensor noise pattern in open scenarios is addressed. This context is common in practice and quite challenging because of the lack of reference to evaluate statistical similarity measures between image and suspect camera noise patterns. A device identification procedure based on an artific...
Conference Paper
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This paper addresses some practical issues regarding the device identification problem when using the sensor photo-response nonuniformity (PRNU). The PRNU is unique to each digital imaging sensor due to imperfections in the manufacturing process. The motivation for this work comes from some problems found in identifying devices by using threshold s...
Conference Paper
Full-text available
Este documento relata a experiência docente no ensino da disciplina Arquitetura e Organização de Computadores, no curso de Engenharia da Computação da Universidade Federal do Pará. Relata-se a experiência de docência amparada por programa de monitoria, e por ferramenta online para discussão e difusão de conteúdo pertinente. Tanto a monitoria quanto...
Conference Paper
Full-text available
Este trabalho trata de um projeto de extensão desenvolvido pela Faculdade de Engenharia da Computação da Universidade Federal do Pará (UFPA) em parceria com o Centro de Perícias Científicas “Renato Chaves” (CPC-RC), intitulado “Processamento Digital de Sinais Aplicado à Prática Forense: Verificação de Adulteração de Provas Digitais e Assinatura de...
Conference Paper
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Since imaging systems are widespread, digital images are becoming increasingly common in criminal processes. However, their content veracity as well as their validity as criminal proofs are commonly questioned due to the many effortless ways of tampering and editing digital images. This work addresses the device identification issue, which aims to...
Patent
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The present invention relates to method and arrangements for reducing crosstalk in a DSL system. This is achieved by providing the users in the network With a ghost line, i.e. a virtual line that should re?ect the damage to be caused to the remaining users in the network, and that each user allocates the PSDs such that the allocated PSD is optimize...
Conference Paper
Full-text available
This paper addresses the use of full reference metrics in the characterization of perceptual difference in a pair of images, in which one of them is degraded by additive white Gaussian noise (AWGN). Conventional (SNR, PSNR, and CC) and perceptual (MSSIM, IFC, VIF, and C4) full reference metrics are considered. The subjective experiment, which uphol...
Conference Paper
Full-text available
Resumo— Este trabalho considera o uso da SSIM em codificadores de imagem baseados na DCT. Mais especificamente, os autores propõem uma abordagem para adaptar a SSIM média (mean SSIM – MSSIM) ` a estrutura pré-existente do codificador. Tal abordagem também resulta na redução da complexidade computacional associadà a avaliação da métrica em questão....
Conference Paper
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Digital Subscriber Lines (DSL) are today one of the most important means for delivering high-speed data transmission. Dynamic Spectrum Management (DSM) is an emerging technique for dealing with crosstalk, one of the technology's most harmful problems. DSM judiciously designs users' power spectral densities so that the overall system performance is...
Conference Paper
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This paper aims to characterize how the impulse noise impacts on services and applications for a broadband system using an ADSL2+ (Asymmetric Digital Subscriber Line, extended bandwidth) loop. The first approach employs the impulse noise defined in the G.996.1 (Test Procedures for DSL Transceivers) and TR-048 (ADSL Interoperability Test Plan) recom...
Conference Paper
Full-text available
In this paper the spectral features of impulse noise in DSL systems are mapped from the waveform domain onto the symbol domain, considering a QAM receiver. This work can be viewed as part of a full symbol domain model for impulse noise, which should include the amplitude and spectral aspects. Since the available models of impulse noise in DSL are g...
Conference Paper
Full-text available
In this paper three image quality metrics are compared: mean-square error (MSE), noise quality measure (NQM), and structural information metric (SIM). Such a comparison is made in order to evaluate the performance of those different metrics under practical conditions. Experimental results along with statistical indices of performance are provided....
Conference Paper
Full-text available
The paper addresses the issue of perceptual image quality assessment. By using Bayesian networks, we propose a Bayesian composed quality measure (B-CQM). This metric can assess quality in images degraded by combined noise injection and frequency distortion. It presents some advantages with respect to the original CQM approach, such as upholding the...
Conference Paper
Full-text available
This paper addresses the issue of perceptual image quality assessment in image restoration systems. First, experiments are conducted in order to assess quality in images degraded by frequency distortion only. Based on the obtained experimental data, a distortion quality measure (DQM) is proposed. Then, another experiment, whose test images are degr...
Conference Paper
Full-text available
This paper addresses the issue of perceptual image quality assessment and psycho visual quality metric development. Such a study is justified due to expressive number of image processing applications designed for human consumption. Particularly, a measure based on Bayesian networks, called Bayesian composed quality measure (B-CQM), is proposed, whi...
Conference Paper
Full-text available
This paper addresses the issue of perceptual image quality assessment in image restoration systems. Firstly, experiments are conducted to evaluate perceived quality in images degraded only by frequency distortion. Based on the resulting experimental data, a distortion quality measure (DQM) is proposed. Then another experiment, whose test images pre...
Conference Paper
Full-text available
The image restoration via reduced order model Kalman filter (ROMKF) is accomplished in conjunction with a maximum likelihood technique for image/blur parameter estimation purposes. Traditionally, one uses initial condition sensitive optimization algorithms at the estimation stage. This work concerns the use of evolutionary programming (EP) in the p...
Conference Paper
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RESUMO A restauração de imagens através do Filtro de Kalman de Modelo de Ordem Reduzida (FKMOR) é obtida em conjunto com uma técnica baseada no critério de máxima verossimilhança. O referido critério é adotado para estimação dos parâmetros da imagem e da degradação. Tradicionalmente, são usados algoritmos de otimização sensíveis às condições inicia...
Conference Paper
Full-text available
This work presents a laboratory kit designed for the purpose of controlling temperature in liquids. Many different control strategies can be easily evaluated by using this low cost kit. The results of comparative tests with PID controllers designed by two pole placement techniques are presented comprising the following alternatives: a controller wi...

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