Instituto Federal Of Minas Gerais

São João Evangelista, Brazil

Instituto Federal Of Minas Gerais

São João Evangelista, Brazil
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Cabacinha C.D.,Federal University of Minas Gerais | Lafeta B.O.,Instituto Federal Of Minas Gerais
Ciencia Florestal | Year: 2017

This study aimed to evaluate the predictive efficiency of Shannon index (H’) and Pielou Equitability index (J) in forest fragments from the Brazilian Cerrado biome, from the vegetation indices and landscape metrics using artificial neural networks (ANN). Feedforward networks were used and they were trained through a back propagation error algorithm. The variables used as ANN input for simultaneous estimation of indices were: the categorical (H’ and J) and the numbers related to the mean and standard deviation of vegetation indices (NDVI, SAVI, EVI, and MVI5, MVI7) and landscape metrics (AREA, GYRATE, SHAPE, CONTIG, CORE and ENN). It was generated five models of ANN from the functional relationships between numerical variables inherent to vegetation indices in two seasons, a dry season (June) and a rainy season (February). The architecture of the networks was the Multilayer Perceptron (MLP), to estimate simultaneously the H’ and J: 500 using vegetation indices in the wet season (100 for each vegetation index) and 500 in dry (100 for each vegetation index). The precision, accuracy and realism of biological ANN were assessed. The nets built during the rainy season and dry season that used vegetation indices MVI5 (Moisture Vegetation Index) and SAVI (Soil Adjusted Vegetation Index), respectively, were more appropriate, accurate and biologically realistic to estimate both indices H’ and J. The ANN modeling demonstrated to be adequate to estimate the diversity index. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Camargos A.F.P.,Instituto Federal Of Minas Gerais | Camargos A.F.P.,University of Sao Paulo | Silva V.C.,University of Sao Paulo | Guichon J.-M.,CNRS Grenoble Electrical Engineering Lab | Meunier G.,CNRS Grenoble Electrical Engineering Lab
International Journal of High Performance Computing Applications | Year: 2017

We present a performance analysis of a parallel implementation for both preconditioned conjugate gradient and preconditioned bi-conjugate gradient solvers running on graphic processing units (GPUs) with CUDA programming model. The solvers were mainly optimized for the solution of sparse systems of algebraic equations at complex entries, arising from the three-dimensional edge-finite element analysis of the electromagnetic phenomena involved in the open-bound earth diffusion of currents under time-harmonic excitation. We used a shifted incomplete Cholesky (IC) factorization as preconditioner. Results show a significant speedup by using either a single-GPU or a multi-GPU device, compared to a serial central processing unit (CPU) implementation, thereby allowing the simulations of large-scale problems in low-cost personal computers. Additional experiments of the optimized solvers show that its use can be extended successfully to other complex systems of equations arising in electrical engineering, such as those obtained in power-system analysis. © SAGE Publications.

Matuk F.A.,Instituto Federal Of Minas Gerais | Schaefer C.E.G.R.,Federal University of Viçosa | Simas F.N.B.,Federal University of Viçosa | Pereira T.T.C.,University Estadual Of Minas Gerais | And 2 more authors.
Revista Brasileira de Ciencia do Solo | Year: 2017

Quilombolas are Afro-brazilian rural peasants who descended from escaped slaves who tried to carve out territories of autonomy (called Quilombos) by collective organization and resistance. Despite many anthropological and ethnopedological studies, little research has been carried out to identify the agricultural practices and the knowledge of people who live in the Quilombos (Quilombolas). Peasant communities who live from land resources have wide empirical knowledge related to local soils and landscapes. In this respect, ethnopedology focuses on their relationship with local practices, needs, and values. We carried out an ethnopedological evaluation of the soils, landscape and land suitability of the Malhada Grande Quilombola Territory, aiming to examine the local criteria involved in land-use decision making, and evaluate the legitimacy of local knowledge. For this purpose, participatory workshops allowed environmental stratification of the Quilombolas into landscape units, recognition of soil types, and evaluation of land-use criteria. This approach was combined with conventional soil sampling, description, and analysis. The Brazilian System of Soil Classification and its approximations to the WRB/FAO system and the SAAT land evaluation system were compared with the local classificatory systems, showing several convergences. The Quilombolas stratified the local environment into eight landscape units (based on soil, topography, and vegetation) and identified eight soil types with distinct morphological, chemical, and physical attributes. The conventional soil survey identified thirteen soil classes, in the same eight landscape units, organized as soil associations. The apparent contradictions between local knowledge and Pedology were relative since the classification systems were established based on different criteria, goals, and sampling references. Most soils are only suitable for pasture, with restricted agricultural use, due to water or oxygen deficiencies. The current land use was only inconsistent with the technical recommendations when socioecological constraints such as the semiarid climate, land availability, and economic conditions for land management led to overuse of the land. Local knowledge demonstrated its legitimacy and allowed a useful and fruitful exchange of information with the academic view of soil-landscape interplays. Although mostly unknown by the scientific community, local knowledge proved capable of achieving social welfare and food security. In addition, a participatory survey proved to be a core factor for more grounded and detailed data collection on how Quilombolas decide land use on a local scale. © 2017, Revista Brasileira de Ciencia do Solo. All rights reserved.

Souza L.M.C.,Instituto Federal Of Minas Gerais | Souza C.M.,Federal University of Viçosa | Finger F.L.,Federal University of Viçosa
Acta Horticulturae | Year: 2017

The use of lime and fertilizer benefits the crop because most Brazilian soils are acidic and low in nutrients. The objective of this study was to evaluate the ability of two cultivars ('Senador Amaral' and 'Amarela de Carandaí') of arracacha cultivated with Agrosilício and lime (agricultural lime) to absorb the nutrients. The experiment was carried out in Ouro Branco, MG, Brazil. The treatments were: T1 - Dolomitic lime at a dose of 1,000 kg ha-1 (saturation to 60%); T2 - Agrosilício (Harsco Minerals) at a dose of 1,000 kg ha-1; T3 - Agrosilício at a dose of 2,000 kg ha-1 (twice the recommended dose for correcting soil acidity). They were uniformly incorporated into the soil. The roots were manually washed and the plants were separated into shoots (leaves), crown and roots. There was no significant interaction between the cultivars and the treatments performed for calcium in the dry matter of roots. Concerning magnesium, it presented a significant difference in the cultivar 'Amarela de Carandaí'/T2, which showed a high absorption of this element. For some reason the silicon had a significantly different effect in T3 on the leaves and roots. The arracacha can be considered an "intermediate" species regarding silicon accumulation, however it revealed a high concentration of silicon in both shoots and roots in T3; that is why it can be beneficial to postharvest storage. Concerning the economic aspects, the cost-benefit ratio for the use of the calcium silicate must be analyzed.

Ribeiro M.R.,Instituto Federal Of Minas Gerais | Ribeiro M.R.,Federal University of Uberlandia | Barioni M.C.N.,Federal University of Uberlandia | de Amo S.,Federal University of Uberlandia | And 2 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

Preference queries on data streams have been proved very useful for many application areas. Despite of the existence of research studies dedicated to this issue, they lack to support the use of an important implicit information of data streams, the temporal preferences. In this paper we define new operators and an algorithm for the efficient evaluation of temporal conditional preference queries on data streams. We also demonstrate how the proposed operators can be translated to the Continuous Query Language (CQL). The experiments performed show that our proposed operators have considerably superior performance when compared to the equivalent operations in CQL. © 2017, Springer International Publishing AG.

da Silveira F.G.,Instituto Federal Of Minas Gerais | Silva F.F.E.,Federal University of Viçosa | Malhado P.L.S.C.,State University of Southwest Bahia
Revista Brasileira de Saude e Producao Animal | Year: 2012

The main objective of this work was to use the cluster analysis in order to classify nonlinear growth models in relation to different quality fit evaluators when data from the following lambs genetic groups were utilized: Dorper x Morada Nova, Dorper x Rabo Largo e Dorper x Santa Inês. After the choice of the best model, it was also aimed to apply the identity model test in order to identify the most efficient genetic group. The proposed methodology was applied to data of all animals from each group regarding twelve nonlinear models, whose fit quality was measured by determination coefficient, Akaike information criterion, Bayesian information criterion, mean quadratic error of prediction, predicted determination coefficient and convergence percentual. The cluster analysis indicated the von Bertalanffy as the best model for the three data sets. The model identity tests revealed that the Dorper x Santa Inês group presented higher adult weight, therefore this group is recommend for meat production.

Silva C.D.,Federal University of Viçosa | Cerqueira M.S.,Federal University of Viçosa | Moreira D.G.,Instituto Federal Of Minas Gerais | Marins J.C.B.,Federal University of Viçosa
Revista Andaluza de Medicina del Deporte | Year: 2013

Objective. To verify the reliability of maximal heart rate obtained (MHRobt) in official soccer games and to compare it with calculated by equations (MHRpre). Method. The study included 18 soccer players (14 ± 0.6 years, 174 ± 6 cm, 62 ± 6 kg) participant of a Brazilian state championship in U-15 category. The equations were selected [MHR = age-220]; Tanaka et al. [MHR = 208 - (0.7*age)] and Nes et al. [MHR=211 - (0.64*age)] for comparison with MHR obt in competition. Results. Bland-Altman analyze showed good agreement of MHRobt and the CV (1 %) and ICC (0.95 [0.86 - 0.98]) show good reliability of the inter matches. The MHRobt (202 ± 8 bpm) was lower than 220 - age equation (205 ± 1 bpm; P < 0.05) and higher than Tanaka et al. (198 ± 0.4; P < 0.05), with no difference to the Nes et al. equation (202 ± 0.5 bpm) (P > 0.05). Conclusion. MHRobt there is good reliability between soccer matches in competition and it is recommended to use the Nes et al. [MHR = 211 - (0.64 * age)] equation to MHRpre in young soccer players. © 2013 Revista Andaluza de Medicina del Deporte.

Pinho D.S.,Instituto Brasileiro Of Meio Ambiente E Recursos Naturais Renovaveis | de Lima e Borges E.E.,Federal University of Viçosa | Pontes C.A.,Instituto Federal Of Minas Gerais
Revista Arvore | Year: 2010

The aim of this experiment was to evaluate the effect of the accelerated aging in the vigor and viability of Anadenanthera peregrina seeds. For the accelerated aging test, the seeds were conditioned in "gerbox" boxes with an aluminum screen separating the seeds from the bottom of the box. Distilled water was added into the bottom and, after that, the boxes were conditioned in aging chambers under temperatures of 40, 50 and 60°C, during periods of 24, 48, 72 and 96 hours. Seeds not submitted to the aging process were used as the control. After each period the seeds were submitted to the following tests: standard germination test, germination speed index, electric conductivity, tetrazolium test, osmopriming and seedling evaluation. Under 40°C, the percentage of germination, the IVG and the percentage of viable seeds for the tetrazolium test decreased significantly. A significant increase in the electric conductivity curve was noticed, as the period in the aging chamber increased. The seeds lost all their viability when submitted to the aging chamber from periods longer than 96 hours, as well as those submitted to temperatures of 50° and 60°C. In the seedling evaluation, all the parameters analyzed decreased as the seeds stayed in the aging chamber for longer periods, except the percentage of abnormal seedlings and the cool weight of the root, which both increased.

Camargos A.F.P.,Instituto Federal Of Minas Gerais | Camargos A.F.P.,University of Sao Paulo | Silva V.C.,University of Sao Paulo | Guichon J.-M.,CNRS Grenoble Electrical Engineering Lab | Meunier G.,CNRS Grenoble Electrical Engineering Lab
Proceedings - 2014 22nd Euromicro International Conference on Parallel, Distributed, and Network-Based Processing, PDP 2014 | Year: 2014

We present a performance analysis of a parallel implementation to both preconditioned Conjugate Gradient and preconditioned Bi-conjugate Gradient solvers using graphic processing units with CUDA programming model. The solvers were optimized for the solution of sparse systems of equations arising from Finite Element Analysis of electromagnetic phenomena involved in the diffusion of underground currents under time-harmonic current excitation. We used a shifted Incomplete Cholesky factorization as preconditioner. Results show a significant speedup by using the GPU compared to a serial CPU implementation. © 2014 IEEE.

Freitas A.M.S.,Federal University of Ouro Preto | Souza F.T.,Instituto Federal Of Minas Gerais | Freitas M.S.R.,Federal University of Ouro Preto
Thin-Walled Structures | Year: 2010

This work presents a general analysis of drive-in racks, evaluating the influence of each of their components on global stability. In this study, a full-scale test of a drive-in system was carried out. Finite element models were also developed to evaluate global structural stability and component influence on system behavior. The experimental and numerical results show that the connections and base plates have the most significant influence on the system's behavior. This influence is analyzed, an equation that predicts base plate resistance is then proposed, and its results are compared with experimental and numerical results. © 2009 Elsevier Ltd. All rights reserved.

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