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Item Ambiente para busca e visualização de documentos históricos na Web(Perspectivas em Ciência da Informação, 2011-07) Possi, Maurilio de Araujo; Oliveira, Alcione de Paiva; Mendes, Fábio; Queiroz, Jonas Marçal; Moreira, AlexandraDocumentos históricos são ferramentas essenciais para historiadores. Em muitos casos, o acesso aos documentos pode ser difícil em função de inúmeros fatores, tais como a distância, segurança e fragilidade do documento. Uma forma de contornar esse problema é a digitalização e disponibilização do acesso em uma rede de comunicação, a Internet. Este artigo apresenta um ambiente para visualização de documentos históricos, desenvolvido dentro do projeto de Digitalização de manuscritos dos acervos dos Cartórios do 1º. e 2º. Ofícios do Arquivo Histórico da Casa Setecentista de Mariana - PHAN.Item Sowing date reduces the incidence of wheat blast disease(Pesquisa Agropecuária Brasileira, 2016-05) Coelho, Maurício Antônio de Oliveira; Torres, Gisele Abigail Montan; Cecon, Paulo Roberto; Santana, Flávio MartinsThe objective of this work was to assess the effect of sowing date on the intensity of wheat blast disease, as well as the yield losses caused by this disease in different wheat (Triticum aestivum) genotypes. The experiments were conducted in 2013 at the Sertãozinho experimental station of Empresa de Pesquisa Agropecuária de Minas Gerais (Epamig), in the municipality of Patos de Minas, in the state of Minas Gerais, Brazil. Fourteen wheat genotypes and two sowing dates were evaluated. The experimental design was a randomized complete block with three replicates. The evaluated variables were: incidence, severity, thousand grain weight (TGW), grain yield, and yield losses. A disease index (DI) was calculated, based both on the incidence and the severity of the disease, to measure blast intensity in wheat. The sowing date significantly affected DI, TGW, and grain yield. Significant linear correlations were observed between DI and yield losses (0.89), between losses and TGW (-0.85), and between losses and grain yield (-0.93). For wheat blast, DIs greater than or equal to 0.5 indicate potential yield losses equal to or greater than 70%. The EP063030 line and the MGS Brilhante and BRS 264 cultivars are the most tolerant to blast, when exposed to high disease pressure.Item Ecocardiografia de gatos com tirotoxicose induzida(Ciência Rural, 2010-04) Martins Filho, Sebastião; Oliveira, Daniel Capucho de; Borlini, Daniel Cometti; Santos, Warley Gomes dos; Monteiro, Jessica Nascimento Moraes; Costa, Lorena Adão Vescovi Séllos; Sobrinho, Aloir Queiroz de Araújo; Costa, Fabiano SéllosO hipertiroidismo é uma doença multissistêmica caracterizada pela elevação dos níveis séricos dos hormônios tireoidianos, sendo uma endocrinopatia comum em gatos. O objetivo deste trabalho foi avaliar possíveis alterações cardíacas pelo exame ecocardiográfico em gatos com tirotoxicose induzida. Foram utilizados nove gatos adultos, sem distinção de sexo ou raça e sem alterações que pudessem interferir nos resultados do estudo. Para indução à tirotoxicose, foram administrados, por via oral, comprimidos, na dose de 150µg kg-1 de levotiroxina sódica, a cada 24 horas, durante 70 dias. Os exames foram realizados em dois momentos: um momento antes da indução e outro ao término do protocolo experimental. Dos parâmetros avaliados, foi observada diminuição estatisticamente significativa nos valores de diâmetro interno do ventrículo esquerdo, tanto na sístole, quanto na diástole. O diâmetro diastólico (DDVE) médio nos animais variou de 14,97mm, no momento inicial, para 13,27mm, no momento final. Os valores médios do diâmetro sistólico (DSVE) variaram de 8,92mm para 7,92mm, nos momentos inicial e final, respectivamente. Os outros parâmetros avaliados não sofreram alterações. Dessa forma, já foi possível caracterizar alterações cardiovasculares secundárias ao excesso dos hormônios tiroidianos nesse curto prazo de indução, porém não havendo a instalação de um quadro de insuficiência cardíaca congestiva. Ressalta-se a necessidade de um diagnóstico precoce do hipertiroidismo felino para evitar a evolução dos efeitos cardiovasculares dessa enfermidade.Item Comparação bayesiana de modelos com uma aplicação para o equilíbrio de Hardy-Weinberg usando o coeficiente de desequilíbrio(Ciência Rural, 2011-04) Reis, Ricardo Luis dos; Muniz, Joel Augusto; Silva, Fabyano Fonseca e; Sáfadi, Thelma; Aquino, Luiz Henrique deO equilíbrio de Hardy-Weinberg é um dos principais assuntos estudados pela Genética de populações. Neste contexto, o presente trabalho aborda a análise e a comparação bayesiana de modelos utilizando o coeficiente de desequilíbrio (D A ). Para isso, realizou-se um estudo de simulação no qual as seguintes distribuições a priori foram consideradas: Dirichlet (modelo 1); beta - função degrau uniforme (modelo 2); uniforme - função degrau uniforme (modelo 3); e as prioris independentes uniformes (modelo 4). Exemplos de aplicação a dados reais de grupos raciais também são apresentados e discutidos. As amostras das distribuições marginais a posteriori para os parâmetros de interesse foram obtidas mediante o algoritmo Metropolis-Hastings, o qual foi implementado no software livre R. A convergência das cadeias geradas por este algoritmo foi monitorada pelos critérios de Geweke e Gelman & Rubin, os quais estão implementados no pacote BOA do R. Quanto às comparações entre os modelos, efetuadas por meio do fator de Bayes, observa-se que, para os dados simulados, o modelo 4 é o mais indicado para os casos de D A =0,146, D A =0,02 e D A =-0,02 com n=200; o modelo 2 é o mais indicado para D A =-0,02 e n=50 e o modelo 3 é o mais indicado para D A =-0,02 e n=1000. Para os dados reais, em cada caso analisado, nota-se uma grande diferenciação na escolha de modelos, em que apenas o modelo 1 não é recomendado.Item Design of a corporate SDI in power sector using a formal model(Infrastructures, 2017) Oliveira, Italo L.; Câmara, Jean H. S.; Torres, Rubens M.; Lisboa-Filho, JugurtaGeospatial data are essential for the decision-making process. However, obtaining and keeping such data up to date usually require much time and many financial resources. In order to minimize the production costs and incentivize sharing these data, countries are promoting the implementation of Spatial Data Infrastructures (SDI) at the different public administration levels. The International Cartographic Association (ICA) proposes a formal model that describes the main concepts of an SDI based on three of the five viewpoints of the Reference Model for Open Distributed Processing (RM-ODP). Afterwards, researchers extended ICA’s model to describe, more properly, the actors, hierarchical relationship and interactions related to the policies that drive an SDI. However, the proposed extensions are semantically inconsistent with the original proposal. Moreover, the use of ICA’s formal model and its extensions has not been assessed yet to specify a corporate-level SDI. This study describes the merger of actors and policies proposed by the ICA and its extensions in order to eliminate differences in the semantics or terminology among them. This unified model was applied to specify a corporate SDI for a large Brazilian corporation, the Minas Gerais Power Company (Companhia Energética de Minas Gerais (Cemig)), which is comprised of about 200 companies in the power sector. The case study presents part of the specification of the five RM-ODP viewpoints, i.e., the three viewpoints featured in ICA’s formal model (Enterprise, Information, and Computation) and the other two viewpoints that make up the RM-ODP (Engineering and Technology). The adapted ICA’s model proved adequate to describe SDI-Cemig. In addition, the case study may serve as an example of the specification and implementation of new SDIs, not only corporate ones, but also of public agencies at any hierarchical level.Item JetsonLEAP: A framework to measure power on a heterogeneous system-on-a-chip device(Science of Computer Programming, 2019-03-15) Gull, Christopher; Nacif, José; Bessa, Tarsila; Quintão, Pedro; Pereira, Fernando Magno Quintão; Frank, MichaelComputer science marches towards energy-aware practices. This trend impacts not only the design of computer architectures, but also the design of programs. However, developers still lack affordable and accurate technology to measure energy consumption in computing systems. The goal of this paper is to mitigate such problem. To this end, we introduce JetsonLEAP, a framework that supports the implementation of energy-aware programs. JetsonLEAP consists of an embedded hardware, in our case, the NVIDIA Jetson TK1 development board, a circuit to control the flow of energy, of our own design, plus a library to instrument program parts. We discuss two different circuit setups. The most precise setup lets us reliably measure the energy spent by 225,000 instructions, the least precise, although more affordable setup, gives us a window of 975,000 instructions. To probe the precision of our system, we use it in tandem with a high-precision, high-cost acquisition system, and show that results do not differ in any significant way from those that we get using our simpler apparatus. Our entire infrastructure – board, power meter and both circuits – can be reproduced with about $500.00. To demonstrate the efficacy of our framework, we have used it to measure the energy consumed by programs running on ARM cores, on the GPU, and on a remote server. Furthermore, we have studied the impact of OpenACC directives on the energy efficiency of high-performance applications.Item Visualization in Big Data: a tool for pattern recognition in data stream(Revista de Sistemas de Informação da FSMA, 2018-01) Soares, Victor Hugo Andrade; Santos, Joelson Antônio dos; Naldi, Murilo CoelhoThe development of new technologies is responsible for the generation and storage of continuous and massive amounts of data. Such type of data is known as data stream. The analysis of data streams may be advantageous in many fields, like bioinformatics, medicine, companies and others, as it may result in important information about the data. In this work, we propose a new software tool for Data Visualization that permits the analysis of the evolution of clusters in real time during the data streaming. The proposed visualization tool is add-on for SAMOA, a new variant of MOA (Massive Online Analysis) for massive data streams mining and processing distribution.Item Erratum to: Mirnacle: machine learning with SMOTE and random forest for improving selectivity in pre-miRNA ab initio prediction(BMC Bioinformatics, 2017) Marques, Yuri Bento; Oliveira, Alcione de Paiva; Vasconcelos, Ana Tereza Ribeiro; Cerqueira, Fabio RibeiroMicroRNAs (miRNAs) are key gene expression regulators in plants and animals. Therefore, miRNAs are involved in several biological processes, making the study of these molecules one of the most relevant topics of molecular biology nowadays. However, characterizing miRNAs in vivo is still a complex task. As a consequence, in silico methods have been developed to predict miRNA loci. A common ab initio strategy to find miRNAs in genomic data is to search for sequences that can fold into the typical hairpin structure of miRNA precursors (pre-miRNAs). The current ab initio approaches, however, have selectivity issues, i.e., a high number of false positives is reported, which can lead to laborious and costly attempts to provide biological validation. This study presents an extension of the ab initio method miRNAFold, with the aim of improving selectivity through machine learning techniques, namely, random forest combined with the SMOTE procedure that copes with imbalance datasets. By comparing our method, termed Mirnacle, with other important approaches in the literature, we demonstrate that Mirnacle substantially improves selectivity without compromising sensitivity. For the three datasets used in our experiments, our method achieved at least 97% of sensitivity and could deliver a two-fold, 20-fold, and 6-fold increase in selectivity, respectively, compared with the best results of current computational tools. The extension of miRNAFold by the introduction of machine learning techniques, significantly increases selectivity in pre-miRNA ab initio prediction, which optimally contributes to advanced studies on miRNAs, as the need of biological validations is diminished. Hopefully, new research, such as studies of severe diseases caused by miRNA malfunction, will benefit from the proposed computational tool.Item Analysis of the coffee harvesting process using an electromagnetic shaker(Acta Scientiarum. Agronomy, 2010-07) Santos, Nerilson Terra; Santos, Fábio Lúcio; Queiroz, Daniel Marçal de; Pinto, Francisco de Assis de CarvalhoHarvesting is one of the most important operations in coffee production systems. This operation has a high cost and impact on the final quality of the product. To reduce production costs, producers are looking for ways to mechanize this operation. Harvesting machines generally detach fruits from the coffee plant by vibration and/or impact. The objective of this work was to study the effect of the amplitude and frequency of vibration on the efficiency of coffee fruit harvesting. Vibration tests of coffee branches were performed in a laboratory using an electromagnetic shaker. The tests were performed using amplitudes in the range of 3.75 to 7.50 mm and frequencies from 13.33 to 26.67 Hz. Coffee branches from two different varieties were used for evaluation, Catuai Vermelho and Mundo Novo. It was verified that harvesting efficiency is directly related to the acceleration reached by the fruits during the harvesting process. The frequencies of 23.33 and 26.67 Hz and amplitudes of 6.25 and 7.50 mm resulted in the highest harvesting efficiency of ripe coffee cherries for both varieties. However, the harvesting efficiency for the Mundo Novo variety was higher than that of the Catuai Vermelho variety at the studied frequency and amplitude ranges in this work.Item An iterated greedy algorithm for total flow time minimization in unrelated parallel batch machines with unequal job release times(Engineering Applications of Artificial Intelligence, 2019-01) Arroyo, José Elias C.; Leung, Joseph Y.-T.; Tavares, Ricardo GonçalvesThis paper investigates the problem of scheduling a set of jobs with arbitrary sizes and non-zero release times on a set of unrelated parallel batch machines with different capacities so as to minimize the total flow time of the jobs. The total flow time, defined as the total amount of time that the jobs spend in the system (i.e. the period between the job release dates and its completion times), is one of the most important objectives in scheduling problems, since it can lead to stable utilization of resources and reduction of working-in-process inventory. Motivated by the computational complexity of the problem, a simple and effective iterated greedy (IG) algorithm is proposed to solve it. The IG algorithm uses an efficient greedy heuristic to reconstruct solutions and a local search procedure to further enhance the solution quality. In attempting to obtain optimal solutions for small-medium size instances, a mixed integer programming model for the problem is also presented. The performance of the proposed algorithm is tested on a comprehensive set of small, medium and large benchmark of randomly generated instances, and is compared to three benchmark meta-heuristic algorithms (Discrete Differential Evolution, Ant Colony Optimization and Simulated Annealing) recently proposed for similar parallel batch machine scheduling problems. Experimental results and statistical tests show that the proposed algorithm is significantly superior in performance than the other algorithms