1,113 research outputs found

    Optimal Categorical Attribute Transformation for Granularity Change in Relational Databases for Binary Decision Problems in Educational Data Mining

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    This paper presents an approach for transforming data granularity in hierarchical databases for binary decision problems by applying regression to categorical attributes at the lower grain levels. Attributes from a lower hierarchy entity in the relational database have their information content optimized through regression on the categories histogram trained on a small exclusive labelled sample, instead of the usual mode category of the distribution. The paper validates the approach on a binary decision task for assessing the quality of secondary schools focusing on how logistic regression transforms the students and teachers attributes into school attributes. Experiments were carried out on Brazilian schools public datasets via 10-fold cross-validation comparison of the ranking score produced also by logistic regression. The proposed approach achieved higher performance than the usual distribution mode transformation and equal to the expert weighing approach measured by the maximum Kolmogorov-Smirnov distance and the area under the ROC curve at 0.01 significance level.Comment: 5 pages, 2 figures, 2 table

    Direct evaluation of mixed mode i+ii cohesive laws of wood by coupling mmb test with dic

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    grant number FCOMP-01-0124-287 FEDER-022692Governing cohesive laws in mixed mode I+II loading of Pinus pinaster Ait. are directly identified by coupling the mixed mode bending test with full-field displacements measured at the crack tip by Digital Image Correlation (DIC). A sequence of mixed mode ratios is studied. The proposed data reduction relies on: (i) the compliance-based beam method for evaluating strain energy release rate; (ii) the local measurement of displacements to compute the crack tip opening displacement; and (iii) an uncoupled approach for the reconstruction of the cohesive laws and its mode I and mode II components. Quantitative parameters are extracted from the set of cohesive laws components in function of the global phase angle. Linear functions were adjusted to reflect the observed trends and the pure modes (I and II) fracture parameters were estimated by extrapolation. Results show that the obtained assessments agree with previous experimental measurements addressing pure modes (I and II) loadings on this wood species, which reveals the appropriateness of the proposed methodology to evaluate the cohesive law under mixed mode loading and its components.publishersversionpublishe

    The Role of Yeast and Lactic Acid Bacteria in the Production of Fermented Beverages in South America

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    Fermentation is one of the oldest forms of food preservation in the world. In South America, most fermented beverages are nondairy products featuring several other food raw materials such as cereals, fruits, and vegetables. Generally, natural fermentations are carried out by yeast and lactic acid bacteria forming a complex microbiota that acts in cooperation. Yeast have a prominent role in the production of beverages, due to the ability to accumulate high levels of ethanol and to produce highly desirable aroma compounds, but lactic acid bacteria are particularly important in fermentation because they produce desirable acids, flavor compounds, and peptides that inhibit the growth of undesirable organisms. Among the South America beverages based on cereals and vegetables, the fermented beverages chicha, caxiri, cauim and champús, and cachaça, a fermented and distilled beverage, could be cited. Genetic and physiological analyses of Saccharomyces cerevisiae strains isolated from cachaça have been shown to present interesting traits for beer production, such as flocculation and production of aroma compounds, fundamental to high-quality beer. The study of these traditional beverages allows the identification of new microorganism strains displaying enhanced resistance or new flavor and aroma profiles that could lead to applications in several industries and ultimately new products

    Desempenho do consórcio entre repolho e rabanete com pré-cultivo de crotalária, sob manejo orgânico.

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    Foram conduzidos dois experimentos no Sistema Integrado de Produção Agroecológica, em Seropédica, (RJ), durante dois anos consecutivos. O objetivo foi avaliar o desempenho do consórcio entre as culturas de repolho e rabanete com pré-cultivo de crotalária, sob manejo orgânico. Usou-se delineamento experimental de blocos ao acaso com sete repetições, em parcelas subdivididas, representando um fatorial 2 x 3, sendo o primeiro fator o pré-cultivo, com Crotalaria juncea e pousio (vegetação espontânea); e o segundo fator o sistema de cultivo (consórcio entre repolho e rabanete e os respectivos monocultivos). Não houve diferença significativa no tocante à produtividade do repolho ou rabanete, entre C. juncea e pousio, independentemente do tipo de manejo (monocultivos ou consórcio). O desenvolvimento do repolho não foi influenciado pela presença do rabanete, no consórcio entre essas espécies sob cultivo orgânico. O rabanete sob consórcio apresentou redução no diâmetro médio, massa média e produtividade de raízes, sem, contudo,desqualificar o padrão comercial das raízes colhidas. Considerando a média dos dois anos experimentais, o IEA atingiu 1,59, o que indicou a viabilidade do consórcio, otimizando práticas culturais, incluindo adubação,capina e irrigação

    Surgical Myocardial Revascularization of Patients with Ischemic Cardiomyopathy and Severe Left Ventricular Disfunction

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    OBJECTIVE: To determine long-term survival, identify preoperative factors predictive of a favorable outcome, and assess functional improvement after coronary artery bypass grafting in patients with advanced left ventricular dysfunction. METHODS: Between 1995 and 2001, 244 patients who underwent coronary artery bypass grafting and had a preoperative left ventricular ejection fraction less than or equal to 35% were included. left ventricular ejection fraction was determined by uniplanar or biplanar ventriculography during left heart catheterization. Indication for surgery was predominance of tissue viability. Functional improvement was evaluated through echocardiography and gated scintigraphy at exercise/ rest. Survival was determined by Kaplan-Meier analysis. RESULTS: Mean left ventricular ejection fraction was 29±4% (ranged from 9% to 35%). An average of 3.01 coronary bypass grafts per patient were performed. In-hospital mortality was 3.7% (9 patients). The 4-year survival rate was 89.7%. Multivariate correlates of favorable short- and long-term outcome were preoperative New York Heart Association Funcional classification for congestive heart failure class I/II, lower PAsP, higher left ventricular ejection fraction and gated left ventricular ejection fraction Ex/Rest ratio >5%. Left ventricular ejection fraction rise from 32±5% to 39±5%, p <0.001. Gated left ventricular ejection fraction at exercise/ rest increased markedly after surgery: from 27±8%/ 23±7% to 37±5%/ 31±6%, p <0.001. CONCLUSIONS: In selected patients with severe ischemic left ventricular dysfunction and predominance of tissue viability, coronary artery bypass grafting may be capable of implement preoperative clinical/ functional parameters in predicting outcome as left ventricular ejection fraction and gated left ventricular ejection fraction at exercise/ rest

    Os rios na paisagem urbana: as modificações através do tempo em Chapecó, SC, Brasil

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    O objetivo deste trabalho foi apresentar a dinâmica das transformações das paisagens de rios urbanos de Chapecó, SC ao longo do tempo, contribuindo com informações para planejamento e tomada de decisão no presente e futuro. Chapecó possui 213. 179 habitantes, 7% residentes no rural e 93% no urbano. O levantamento das imagens dos rios antigos se deu através do Centro de Memórias do Oeste – CEOM. Nas imagens e notícias, percebe-se que ao longo do tempo, a paisagem dos córregos e rios urbanos em Chapecó foi alterada especialmente pela urbanização desenfreada, sem respeito aos planos originais. Fica evidente que a função dos rios no passado foi para servir de canal de escoamento do que não era necessário à população, o que se reflete culturalmente até nos dias atuais, visto que a população em muitos casos desdenha a presença do rio. Este fato talvez seja justificado por muitos destes rios terem sido ocultados da paisagem no município de Chapecó

    Formação dos aquíferos Serra Geral e Guarani: uma volta ao passado

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    A utilização das águas subterrâneas é realizada há milhares de anos, porém, atualmente essa demanda aumentou consideravelmente, principalmente em regiões onde a qualidade da água superficial está comprometida mas continua sendo essencial para o desenvolvimento de atividades econômicas e para o abastecimento público, como nas regiões da Serra e Oeste Catarinense. A ocupação do Oeste Catarinense ocorreu de maneira não sustentável desde meados de 1912, com a chegada das empresas colonizadoras, trazendo inúmeras consequências e problemas vividos na atualidade. Diante disso, o objetivo do presente trabalho é apresentar a formação dos aquíferos Serra Geral e Guarani, na Bacia Geológica do Paraná, visando disseminar esse conhecimento para a população com o propósito de que os mesmos possam assim criar uma cultura de preservação e uso sustentável das águas subterrâneas. Em termos metodológicos, realizou-se uma compilação da bibliografia, sendo necessário fazer um resgate histórico e teórico sobre os processos que deram origem às formações aquíferas na região Oeste de Santa Catarina, tendo como base um capítulo da tese de doutorado de uma das autoras

    Factor Analysis and the Social Capital Index: A Study at the Brazil / Bolivia Border

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    Objective: The study aimed to build the level of social capital by neighborhoods Guajará-Mirim border region between the State of Rondônia, Brazil and the Republic of Bolivia, which in recent years has been showing signs of social fragility due advance not virtuous practices. Method: This work made use of research in secondary bases as well as in primary bases. The tabulation of qualitative and quantitative data was performed in Excel (2010) and for their processing performance index construction purposes were calculated following the factorial analysis techniques presented by Hair et al. [19] Santana [20, 21]; and Choi [22]. For this, we made use of the statistical tool SPSS (Statistical Package for Social Sciences) for the construction of the indices of social capital. The correlation analysis process was done in Excel. results: It was observed that the capital reached regular levels in Guajará-Mirim neighborhoods not observable, so correlations between the studied parameters, however, it needs to be further studied as factors such as the flooding of the Mamore river may have interfered in any way in the implementation process of the field survey to the residents of the city. It became clear that the municipality of Guajará-Mirim suffers from serious social problems and that most problems are correlated with the increase in alcoholic beverage market in the city and use drugs. However, was not observed as the institutional arrangements are dealing with this problem, that is, as public bodies are relating to discuss actions for concrete solutions to this evil that plagues large portion of the population of Guajará-Mirim, mainly young teenagers residents of Guajá-Mamim. However, we hope to continue this work in order to better understand this mechanism of social network between the actors of this process in the region
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