EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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3 resultados
Resultados da Pesquisa
Item Error variance of short duration sieving.(2018) Resende, Tulio Viegas Bicalho; Luz, José Aurélio Medeiros dan this study, the variance of ordinary sieving test error was determined concerning the specification limit of sized iron ore product by subtracting the fundamental error (described by the Gy's formalism for sampling), from the global error (recoverable from database of historical values). The results allowed the calculation of the confidence interval for the percentage of material finer than the upper screen specification limit. Thereafter, a method to estimate the so-called effectiveness coefficient of the screening operation was developed, which is the ratio between number of particle presentations to passage and the number of oscillations during the material shaking on the screen surface. This estimation was based on the probability statements and particle size distribution of the feed. Considering the size distribution of the products tested in this study, the results have shown that the sieving time could be reduced when determining the percentage of material finer than the upper specification mesh.Item Simulations of EIA screening across jurisdictions : exposing the case for harmonic criteria?(2017) Rocha, Caroline Priscila Fan; Fonseca, Alberto de Freitas CastroScreening is one of the most critical stages in environmental impact assessment (EIA). However, there is no consensus about best approaches to screen development proposals, particularly in large territories with multiple jurisdictions. This study explored the challenges of harmonizing EIA screening criteria across jurisdictions, using Brazilian states as the empirical context. It set out to answer the following question: what would be the screening decisions of approved development projects if they had been licensed in different states? This study selected four cases of projects that had obtained environmental licenses in the state of Minas Gerais, and, based on their data, simulated license applications in other three states in south-eastern Brazil. Interviews helped to determine likely screening decisions. Screening approaches, while similar, varied significantly in terms of choices of threshold criteria across the four states. With the exception of one project type, the projects would face very different EIA requirements in the other jurisdictions. Such differences seem to stem more from political choices than from geographical idiosyncrasies. Implications for policy-making regarding harmonization are discussed.Item Modelamento matemático de peneiramento vibratório (Parte 1) : dimensionamento clássico.(2005) Luz, José Aurélio Medeiros da; Carvalho, Simão Célio deA partição do fluxo em peneira é fortemente dependente da distribuição de probabilidade de passagem de partículas por suas aberturas. Essa probabilidade é influenciada pelas condições de operação e pela relação entre o tamanho de partícula e abertura. Desenvolveu-se um sistema (SimPeneira) para dimensionar peneiras, utilizando o método clássico de dimensionamento (adequadamente modificado), e simular diversos cenários de peneiramento industrial, quantificando o impacto de parâmetros operacionais. Esse artigo descreve a primeira parte de tal sistema, abordando o dimensionamento clássico de peneiras vibratórias e revolventes.