873 resultados para modelo linear com resposta em platô


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Pipelines are linear engineering works, designed mostly for transporting oil and its derivatives for long distances, furnishing even the farthermost zones of the country. Due to oil sector needs to ensure for the safety and conservation of its properties, several geotechnical studies are being held at the pipelines field, in order to preserve this important transportation, and also to prevent accidents, which might seriously compromise the environment and the population who lives around it. The OSBRA pipeline, who connects the city of Paulínia to the capital Brasília, is one of these engineering works that deserves to be pointed out. This research, performed at the Ribeirão da Prata Basin, was a pilot study conducted with the main objective of testing the current methodology efficiency, for future applications in the closest watersheds to the OSBRA pipeline. The objective of this research is to analyze flood wave and debris flow processes in a non-fictional watershed, by comparing two different kinds of methods: the first one based on simulation models (software ‘ABC 6’), and the other one by flood wave and debris flow susceptibility mapping. The results from the hydrological modeling were both hydrographs and ietographs that estimated values of outputs and infiltration. To construct the susceptibility maps were necessary three other maps: ground use and occupation maps, divided according to the different protection degrees that were offered to the ground; maps of dam locations in the area and physiographic compartimentation maps, divided according to the local geology. To complete the methodology, the results were collected from both methods for comparison. The obtained product for this methodology was series of data whose different susceptibility degrees to flood wave and debris flow could define the safest route for a pipeline crossing in this watershed...

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For the development of this graduate work of fractal fracture behavior, it is necessary to establish references for fractal analysis on fracture surfaces, evaluating, from tests of fracture tenacity on modes I, II and combined I / II, the behavior of fractures in fragile materials, on linear elastic regime. Fractures in the linear elastic regime are described by your fractal behavior by several researchers, especially Mecholsky JJ. The motivation of that present proposal stems from work done by the group and accepted for publication in the journal Materials Science and Engineering A (Horovistiz et al, 2010), where the model of Mecholsky could not be proven for fractures into grooved specimens for tests of diametric compression of titania on mode I. The general objective of this proposal is to quantify the distinguish surface regions formed by different mechanisms of fracture propagation in linear elastic regime in polymeric specimens (phenolic resin), relating tenacity, thickness of the specimens and fractal dimension. The analyzed fractures were obtained from SCB tests in mode I loading, and the acquisition of images taken using an optical reflection microscope and the surface topographies obtained by the extension focus method of reconstruction, calculating the values of fractal dimension with the use of maps of elevations. The fractal dimension was classified as monofractal dimension (Df), when the fracture is described by a single value, or texture size (Dt), which is a macroscopic analysis of the fracture, combined with the structural dimension (Ds), which is a microscopic analysis. The results showed that there is no clear relationship between tenacity, thickness and fractal values for the material investigated. On the other hand it is clear that the fractal values change with the evolution of cracks during the fracture process ... (Complete abstract click electronic access below)

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Through observation of production process of a Vale do Paraiba’s automobile industry, one can encounter in need of improvement related to large uncertainties and variations in the production environment, a fact that inspired the search for solutions that can respond quickly to these changes. This way, the paper describes the development of a flexible manufacturing model, which aims to optimize the process in an automotive sub-assembly industry of the Paraíba Valley. The main objective is to propose a method to promote viable alternatives to easing the assembly of parallel sub performed the assembly of cars. For the construction of the model was necessary to explore concepts of flexible manufacturing and making the data presented in literature, which were vital to ensure the development of the method. The concepts discussed are usually presented at an undergraduate degree in Engineering. Data compiled by the model are able to serve as a strategic benchmark for decision making by managers. Featuring alternative response variables and uncertainties of the organizational environment, a fact that facilitates the management of human resources and productive

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The N6 Plateau presents an iron-ore occurence in Carajás Mineral Province, standing near to actually operating deposits. Geological mapping in 1:10,000 scale and integration of geochemical, geophysical, petrography and drilling turns possible interpretation of his geological evolution. The mapped area has lithotypes from Archean Grão Pará Group, comprising very lowgrade metamorphic basic rocks and iron formation and an Proterozoic sedimentary association of conglomeratic sandstones called as Caninana Unity. The structural geology in given by a regional scale homoclinal, where the Grão Pará Group strata dips towards SW, as a part of the Northern Limb of the Carajás Fold. Subsequent deformation associated to the installation of the Carajás Shear Zone presents as E-W fold axis. Geochemical evidence permits to consider de Parauapebas Formation as the rocks which has been hydrothermally-altered to outsourcing fluids responsible to deposition of iron formations in the oceanic system, including different signatures which can be interpreted as possible sub-embayments in the Carajás Basin. The iron ore in the area occurs in subsurface as very fine friable hematite generated by supergenous enrichment of the iron formation. The conceived geologic model differs from the current academic proposal on the fact that hydrothermal alteration has been involved on the jaspelite enrichment. Metamorphism on the Parauapebas Formation presents paragenesis considered as ocean-floor metamorphism which precedes de deformation insofar as the rocks show no tectonic fabric referring to shallow crust evolution. Geophysical methods such as magnetometry and gravimetry presents excellent results for structural interpretation in uneven exposed terrain

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Uma das principais alterações ambientais decorrentes da ação antrópica é o efeito de borda, consequência direta da fragmentação, que altera condições microclimáticas nas bordas dos fragmentos. Este processo afeta a biodiversidade, interferindo na dinâmica das comunidades, tanto vegetais, quanto animais, alterando a composição e a estrutura das comunidades. Através da utilização de bioindicadores é possível compreender como alterações nos hábitats interferem nas comunidades locais, ou em processos ecológicos essenciais para a manutenção do ecossistema e da biodiversidade local ou regional. Devido à grande riqueza, abundância e importância em diversos processos ecológicos, como por exemplo, dispersão de sementes e ciclagem de nutrientes, as formigas têm sido utilizadas como indicadores ambientais. Os objetivos deste trabalho foram avaliar como as comunidades de formigas de fragmentos de cerrado respondem ao efeito de borda, especificamente se essa resposta ocorre de forma gradiente ou hábitat-matriz (formigas não estão presentes na borda). Também foi analisado se o tipo de matriz adjacente influencia nessas respostas observadas em 15 paisagens de cerrado circundadas por matrizes de pasto, cana-de-açúcar e eucalipto onde se utilizou armadilhas de queda ao longo de transectos posicionados tanto dentro como fora dos fragmentos. Para a riqueza total de formigas o modelo hábitat-matriz com interferência da matriz foi o que melhor explicou a distribuição. Os modelos que melhor explicaram a riqueza e abundância dos grupos funcionais variaram consideravelmente, o que evidencia a importância de buscar modelos mais complexos (modelo gradiente) que expliquem tanto as respostas mais simples (hábitat-matriz)como as mais multíplices. As comunidades analisadas apresentam diferentes funções dentro do hábitat e das matrizes, dessa forma participam de vários processos ecológicos sendo assim bons indicadores...

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This paper discussed the model of Nash bargaining (NASH, 1950, 1953), which its arbitration function is invariant for the linear transformations. A more robust model was proposed with respect to the incommensurable effect. The result obtained by the optimization process was not influenced by the units or the amplitude values of these measures. The risk and the return is measured in portfolios of assets and defined a risk metric, return and a method to handle the risk and return. For this, we made a review on the main characteristics of Brazilian industry funds and their evolution over the past years, in addition to treating on the risk in the financial market, the importance of portfolio selection and the Markowitz Model. Are made closing remarks, an analysis of the results, some suggests, concerns and how such concerns can be improved and / or explored in future studies

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The objective of this paper is to relate the set of financial ratios that are directly related to the success of public traded companies using a methodological approach and the method of multivariate principal component analysis. This study consists in the use of profitability ratios, debt and liquidity, to define the relationship between financial ratios with the best public traded companies listed in the magazine Exame Melhores e Maiores of 2013. Multivariate analysis was used to reduce the dimensionality of multivariate data, making linear combinations of the original variables (financial ratios) and express the data in principal components that result in new variables that contains much of the original data. As a result, we got the optimal number of five principal components, and both represent 95.6% of the original data. Among of all financial ratios, we can highlight the direct relationship between profitability ratios for the first principal component, and the direct relationship between the liquidity ratios, both inversely related with non-capital participation rates and degree indebtedness to the second principal component

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Pós-graduação em Engenharia Elétrica - FEIS

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Matematica Aplicada e Computacional - FCT

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Introduction: the assessment of the activity of rheumatoid arthritis and juvenile idiopathic arthritis is made by means of different tools, respectively DAS-28 and JADAS.Objective: To compare DAS-28 and JADAS with scores of 71, 27 and 10 joint counts in juvenile idiopathic arthritis.Method: A secondary analysis of a phase III placebo-controlled trial, testing safety and efficacy of abatacept was conducted in 8 patients with 178 assessment visits. Joint count scores for active and limited joints, physician's and parents'global assessment by 0-10 cm Visual Analog Scale, and erythrocyte sedimentation rate normalized to 0-10 scale, in all visits. The comparison among the activity indices in different observations was made through Anova or adjusted gamma model. The paired observations between DAS-28 and JADAS 71, 27 and 10, respectively, were analyzed by linear regression.Results: There were significant differences among individual measures, except for ESR, in the first four months of biological treatment, when five of the eight patients reached ACR-Pedi 30, with improvement. The indices of DAS-28, JADAS 71, 27 and 10 also showed significant difference during follow-up. Linear regression adjusted model between DAS-28 and JADAS resulted in mathematical formulas for conversion: [DAS-28 = 0.0709 (JADAS 71) + 1.267] (R-2 = 0.49); [DAS-28 = 0.084 (JADAS 27) + 1.7404] (R-2 = 0.47) and [DAS-28 = 0.1129 (JADAS-10) + 1.5748] (R-2 = 0.50).Conclusion: The conversion of scores of DAS-28 and JADAS 71, 27 and 10 for this mathematical model would allow equivalent application of both in adolescents with arthritis. (C) 2014 Elsevier Editora Ltda. All rights reserved.

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This work was carried out to evaluate the functional response of Cryptolaemus montrouzieri Mulsant, 1850 (Coleoptera: Coccinellidae) fed with Planococcus citri Risso, 1813 (Hemiptera: Pseudococcidae) reared on a pumpkin hybrid (Cucurbita maxima x Cucurbita moscata) (Cucurbitaceae), seedlings of Rangpur lime (Citrus limonia) Rutaceae) and potato (Solanum tuberosum) (Solanaceae) at two temperatures. The predation rate of C. montrouzieri was measured using Petri dishes of 15 cm diameter with 1, 2, 4, 8, 16 and 24 adults of P. Citri. One third instar larva, one fourfh instar and one newly emerged adult (without differentiation of sex) of C. montrouzieri were added to each plate. The study was conducted in climatic chambers at temperatures of 25 and 30 degrees C and photophase of 12 hours. The predation rate was evaluated after 24 hours of prey exposition to the predator, by counting the number of preys trapped in the different treatments and control. The statistical design was completely randomized with four treatments x 6 subplots with 7 repetitions, the two temperatures. The values obtained were subjected to analysis of variance, to relate the number of scales preyed by larvae and adults of C. montrouzieri set up in different substrates. The amount of prey consumed by larvae and adults of the predator increased with increasing the prey density until it reaches a plateau, characterizing functional response type II. In general, the number of scales preyed by larvae and adults of C. montrouzieri was higher on potato and under temperature of 30 degrees C.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)