Presidente Olegário, Brazil
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The Quadrilátero Ferrífero region, in the State of Minas Gerais, became internationally known due to the exploitation of gold in the eighteenth century. In this paper, we will present background values for arsenic in alluvial sediments from areas that were heavily affected by the exploitation of gold in the past, in the Carmo River Basin. The analyses of the facies succession of the alluvial profiles were carried out in the sedimentary deposits of flood plains, cutbank and alluvial terraces; this being the foundation for obtaining the arsenic background in the facies of the channel and flood plains. From the knowledge of the background obtained by the statistical method, and based on the construction of cumulative frequency curves on a linear scale, geochemical maps were generated in the SIG system. The acquisition of the background values and the geochemical map for arsenic in the Carmo River Basin, representing areas with anomalous concentrations of this element, are essential for the diagnosis and environmental planning of a mining district potentially contaminated by arsenic.

Gastaldello D.S.,São Paulo State University | Souza A.N.,São Paulo State University | Ramos C.C.O.,University of Sao Paulo | Da Costa Junior P.,São Paulo State University | Zago M.G.,FATEC
INES 2012 - IEEE 16th International Conference on Intelligent Engineering Systems, Proceedings | Year: 2012

The need for high reliability and environmental concerns are making the underground networks the most appropriate choice of energy distribution. However, like any other system, underground distribution systems are not free of failures. In this context, this work presents an approach to study underground systems using computational tools by integrating the software PSCAD/EMTDC with artificial neural networks to assist fault location in power distribution systems. Targeted benefits include greater accuracy and reduced repair time. The results presented here shows the feasibility of the proposed approach. © 2012 IEEE.

Suassuna J.F.,Federal University of Campina Grande | Fernandes P.D.,Bairro University | do Nascimento R.,Federal University of Campina Grande | de Oliveira A.C.M.,FATEC | And 2 more authors.
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2012

Knowing the importance of the rootstocks for the success of the citrus crop and its influence on tolerance to stress factors, this study was conducted in order to evaluate tolerance of citrus rootstocks to water stress studying two factors: water management ('without stress' and 'under stress' and in this latter case, the irrigation was based on 50 and 25% moisture of field capacity) and rootstocks factor (10 citrus genotypes provided by Citrus Breeding Program of Embrapa Cassava and Tropical Fruits). A randomized block design was adopted with three replications and 15 plants per plot. Shoot, leaves, stem, root and total dry mass, root/shoot ratio, leaf weight ratio and relative yield were evaluated. Water deficit reduced the total dry mass and increased the root/shoot ratio in some rootstocks. Leaf dry mass is the most sensible variable in citrus rootstocks under water deficit. 'TSKFL CTTR x-017' has a significant capacity of tolerance to drought, with promising potential for use in areas under drought conditions.

Silva J.R.V.,Syngenta | Da Silva A.C.,São Paulo State University | Pereira M.R.R.,FATEC | Martins D.,São Paulo State University
Engenharia Agricola | Year: 2016

Surfactant use in spray solutions has a major advantage of reducing droplet surface tension and increasing deposition. We aimed to evaluate droplet deposition on cattail plants (Typha subulata) using food coloring (Brilliant Blue - FD & C-1) as marker added to spray solution at two different growth stages: vegetative (4 leaves) and flowering (5 leaves). The treatments were arranged in a completely randomized design with four replications and five plants per plot (16.2-L tanks). Treatments consisted of adding into spray solutions Brilliant Blue alone (control), Brilliant Blue + 0.5% v/v Aterbane and Brilliant Blue + 0.01% v/v Silwet. Spraying was performed by a pressurized CO2 sprayer at 220 kPa using two Teejet XR 8002 nozzles at a spray volume of 200 L ha-1. We observed that surfactant addition provided uniform deposition of spray solution on T. subulata plants at both growth stages compared to treatments without surfactant. However, this product has not increased spray deposits on cattail leaves at both stages.

The collaborative product development is essential for companies to increase the innovation degree of their products. Companies must follow the critical success factors (CSF) in order to achieve the expected results. There is a set of papers that identified critical success factors (CSF) for collaborative projects; however, there is no paper verifying those factors in Brazil, especially in the Agricultural Machinery Industry. This article aims to verify whether the CSFs identified in the literature could be used in this context. A bibliographical review was carried out to identify a CSF list. After that, a single case study was developed, using the project as unit of analysis. Two successful and collaborative projects were evaluated. The results described new CSFs and reinforced others, as factors related to relationship equality and universality.

Queiroz J.R.G.,São Paulo State University | Junior A.C.D.S.,São Paulo State University | Pereira M.R.R.,Fatec | Martins D.,São Paulo State University
Revista Brasileira de Fruticultura | Year: 2016

Knowledge regarding the use of herbicides in palms fruit is almost nonexistent. Thus, the objective of this work was to evaluate the initial development of seedlings on Euterpeoleraceae and Euterpeedulis. Studies were conducted in two seasons (February 2013 and January 2014) for each species in a completely randomized design with four replications. The treatments tested were: fluazifop-p-butyl (93,8 g ha-1), sethoxydim (184 g ha-1), quizalofop-p-ethyl (75 g ha-1), (clethodim + fenoxaprop-p-ethyl) (50 + 50 g ha-1), fomesafen (225 g ha-1), lactofen (168 g ha-1), nicosulfuron (50 g ha-1), MSMA (1.422 g ha-1), and a control without herbicide. Spraying was performed over seedlings with 45-50 cm tall. Visual evaluations of phytotoxicity, plant height at 7, 14, 21, 28, 35, 42 e 49 days after spraying (DAS) and at the end of the dry mass of shoot.Visual observations showed that all herbicides were selective to the two palm species studied. Some visual injury symptoms eventually noticed (maximum 14%), dissipated of these occurred over time 49 DAS. Analysis of the height and dry mass accumulation of plants showed that E. oleracea palm presented more tolerant to herbicides when compared to E. edulis.All the herbicides can be recommended to the E. oleracea. As to E.edulis, only the herbicidessethoxydim(184 g ha-1), nicosulfuron (50 g ha-1)and mixing clethodim + fenoxaprop-p-ethyl(50 + 50 g ha-1) they did not affect the initial development of seedlings in the two years of study. © 2016, Sociedade Brasileira de Fruticultura. All rights reserved.

Isotani S.,Carnegie Mellon University | Isotani S.,University of Sao Paulo | Mizoguchi R.,Osaka University | Capeli O.M.,FATEC | And 4 more authors.
Computers and Education | Year: 2013

When the goal of group activities is to support long-term learning, the task of designing well-thought-out collaborative learning (CL) scenarios is an important key to success. To help students adequately acquire and develop their knowledge and skills, a teacher can plan a scenario that increases the probability for learning to occur. Such a scenario defines pedagogically sound structures that prevent off-task behavior and engage students in more meaningful interactions. The main difficulty in designing effective CL scenarios is transforming the teacher's intentions into elements that constitute the learning scenario. This problem is frequently observed when novice teachers attempt to improve the quality of learning and instruction by blending collaborative activities with individual activities without careful planning. With the goal of helping teachers in planning collaborative scenarios, we have developed an intelligent authoring tool referred to as CHOCOLATO using Semantic Web technologies (e.g. ontologies) in order to represent knowledge about different pedagogies and practices related to collaboration. Through the use of this knowledge, CHOCOLATO can provide intelligent guidance that helps teachers to create theory-based CL scenarios which has proven to be effective in a variety of situations. We evaluated it by conducting two experiments. We were interested in verifying whether the recommendations given by CHOCOLATO help novice teachers to design pedagogically sound CL activities, and if these activities help students to learn collaboratively in real classroom settings. The first experiment had the participation of 58 pre-service teachers that created CL scenarios with and without our authoring tool and the second experiment was carried out in a Brazilian public school together with 218 students. The results suggest that the guidance provided by CHOCOLATO do help novice teachers plan, understand and share CL scenarios more easily. They also suggest that the continuous utilization of well-designed theory-based CL activities create favorable conditions for students (particularly less knowledgeable ones) to improve their overall performance throughout the school year. © 2012 Elsevier Ltd. All rights reserved.

Cavalini F.C.,FATEC | Jacomino A.P.,University of Sao Paulo | Trevisan M.J.,University of Sao Paulo | Miguel A.C.A.,University of Sao Paulo
Revista Brasileira de Fruticultura | Year: 2015

This research aimed to study the influence of maturation on the quality of ‘Kumagai’ and ‘Paluma’ guavas. Healthy fruits of both cultivars harvested at five maturity stages defined on the basis of skin color, were selected for the absence of mechanical damage and rot and stored under environmental conditions (25±1ºC and 85±5% RH). They were evaluated at the time of harvest and after reaching full maturity as the shelf-life, skin color, pulp firmness, ascorbic acid, soluble solids (SS) and titratable acidity (TA), as well as the SS/TA ratio and the flavor. The results indicated that cv. Kumagai guavas have longer conservation (6.8 days on average) than ‘Paluma’ (3.2 days on average) and that this period is influenced by ripening stage. Regardless of cultivar, guavas harvested in early stages of maturation kept more acid (0.71%) than that those harvested later (0.57%), with the aggravating circumstance that in cv. Kumagai, the harvest in stage 1, resulted in retention of the green color of the skin. The harvest of guava in early stages despite prolonging the shelf-life implies inferior fruit quality. On the other hand, the harvest in more advanced stages of maturation makes necessary the implementation of appropriate conservation techniques to the intrinsic characteristics of each variety, in order to ensure the quality of the fruit offered to the consumer. © 2015, Sociedade Brasileira de Fruticultura. All rights reserved.

Araujo Barros R.,São Paulo State University | Abdalla A.J.,Institute Estudos Avancados | Rodrigues H.L.,FATEC | dos Santos Pereira M.,São Paulo State University
Materials Science Forum | Year: 2014

The 4340 are classified as ultra-high strength steels used by the aviation industry and aerospace applications such as aircraft landing gear and several structural applications, usually in quenched and tempered condition. In this situation occurs reduction of toughness, which encourages the study of multiphasic and bainític structures, in order to maintain strength without loss of toughness. In this study, ferritic-pearlitic structure was compared to bainitic and martensitic structure, identified by the reagents Nital, LePera and Sodium Metabisulfite. Sliding wear tests of the type pin-on-disk were realized and the results related to the microstructure of these materials and also to their hardnesses. It is noted that these different microstructures had very similar behavior, concluding that all three tested pairs can be used according to the request level. © (2014) Trans Tech Publications, Switzerland.

Araujo E.S.R.,FATEC | Costa J.O.,FATEC | De Lima R.O.P.,FATEC | Rodrigues Henriques V.A.,Brazilian Technological Institute of Aeronautics
Materials Science Forum | Year: 2014

Titanium is found in its raw form in nature mainly in rutile, ilmenite, and anatase which appears in abundant quantities in the earth crust. However, its extraction through the conventional process is still very expensive. Powder metallurgy has been used as an alternative technique for production of titanium alloys parts due to its low cost compared with conventional melting techniques. The process involves the use of powders under high pressure and temperature. Using this technique, Ti-10V-2Fe-3Al samples were produced from Ti-Al pre-alloyed powder with additions of different contents of aluminum in order to study the influence of aluminum particles on the formation of residual porosity. After cold uniaxial and isostatic pressing and sintering at 1100°C and 1400ºC, samples were characterized by SEM (Scanning Electron Microscopy), XRD (X-ray Diffraction), EDS (Energy Dispersive Spectrometry) and density analyses. Sintered samples presented homogeneous microstructure and increased densification due to increased content of Ti- Al pre-alloyed powder. © (2014) Trans Tech Publications, Switzerland.

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