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 A hybrid multi-step sensitivity-driven evolutionary polynomial regression enables robust model structure selection.(2022) Gomes, Ruan Gonçalves de Souza; Gomes, Guilherme José Cunha; Vrugt, Jasper A.Evolutionary Polynomial Regression (EPR) has found widespread application and use for model structure development in engineering and science. This hybrid evolutionary approach merges real world data and explanatory variables to generate well-structured models in the form of polynomial equations. The simple and transparent models produced by this technique enable us to explore, via sensitivity analysis, the robustness of the derived models. Yet, existing EPR frameworks do not make explicit use of sensitivity analysis in the selection of robust and high-fidelity model structures. In this paper, we develop a multi-step sensitivity-driven method which combines the strengths of differential evolution and model selection via Monte Carlo simulation to explore the input–output relationships of model structures. In the first step, our hybrid approach automatically determines the optimum number of terms of the polynomial equations. In a subsequent step, our algorithm explores the mean parametric response of each explanatory variable used in the mathematical formulation to select a final model structure. Finally, in our selection of the most robust mathematical structure, we take explicit consideration of the prediction uncertainty of the simulated output. We illustrate and evaluate our EPR method for different engineering problems involving modeling and prediction of the moisture content and creep index of soils. Altogether, our results demonstrate that the use of sensitivity analysis as an integral part of model structure search and selection will lead to robust models with high predictive ability.Item Electrical profiling of vibration-induced dewatering of sand.(2021) Reis, Jonathan Leandro Martins; Luz, José Aurélio Medeiros da; Vardanega, FábioElectrorresistive profiling of moisture inside a quartz sand bed on a pilot-scale vibrating screen was treated here. As electrode or probe configuration for resistivity measurement is concerned, the classical Wenner α array was used, requiring equal electrode spacing, and correct penetration depth and alignment. Here, the influence of small variations in penetration depth and lack of probe collinearity on the moisture readings, using a digital earth resistance tester and copper wires as probes, was evaluated. The penetration depths studied were 50 mm and 55 mm. In turn, the electrode misalignment tested was 10 mm. The only factor that has caused statistically significant effect in measurements was probe penetration depth, at least under the range tested here.Item Coating mortars based on mining and industrial residues.(2020) Mendes, Júlia Castro; Barreto, Rodrigo Rony; Vilaça, Vanessa de Freitas; Lopes, Amanda Vitor; Souza, Henor Artur de; Peixoto, Ricardo André FiorottiThe present work assesses the feasibility of using mining and industrial residues as aggregates of coating mortars in terms of building thermal performance. For this purpose, we investigated four types of aggregates (river sand—REF, iron ore tailings—IOT, friable quartzite—QTZ, and steelmaking slag—SLG). Initially, the specifc gravity (density) and thermal conductivity of the residue-based mortars were experimentally obtained. Subsequently, a sensitivity analysis was performed through energy simulations of two existing dwellings. Mortars with SLG and IOT presented the best performance due to their low thermal conductivity and, more importantly, their high density. Mortars with SLG presented 64% of thermal performance classifcations as “superior” and “intermediate”, versus an average of 53% for the other aggregates. They were followed by those with IOT, REF and lastly those with QTZ. Therefore, these mortars are cost-efective and sustainable solutions to passively improve the thermal performance of buildings, as well as to mitigate the impacts of the disposal of these residues.