1000 resultados para Previsão Estatística


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The piles are one of the most important types of solution adopted for the foundation of buildings. They are responsible for transmitting to the soil in deepe r and resistant layers loads from structures. The interaction of the foundation element with the soil is a very important variable, making indispensable your domain in order to determine the strength of the assembly and establish design criteria for each c ase of application of the pile. In this research analyzes were performed f rom experiments load tests for precast concrete piles and inve stigations of soil of type SPT, a study was performed for obtaining the ultimate load capacity of the foundation through methods extrapolation of load - settlement curve , semi - empirical and theoretic . After that, were realized comparisons between the different methods used for two types of soil a granular behavior and other cohesive. For obtaining soil paramet ers to be used i n the methods were established empirical correlations with the standard penetration number (NSPT). The charge - settlement curves of the piles are also analyzed. In the face of established comparisons was indicated the most reliable semiempirical method Déco urt - Quaresma as the most reliable for estimating the tensile strength for granular and cohesive soils. Meanwhile, among the methods studied extrapolation is recommended method of Van der Veen as the most appropriate for predicting the tensile strength.

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The effects of climate change on human societies have become the focus of many researchers for their research. Understanding weather patterns (circulation of the atmosphere, precipitation, temperature) is essences for predicting extreme weather, but analyze how these extreme events act in our society and look for ways to reduce the impact caused by these events is the great challenge. Using a concept very in the humanities and social sciences to understand these impacts and the adaptation of the society's vulnerability. The objective of this work is to develop and apply a methodology for evaluating fining scale and quantify the vulnerability of the Brazilian Northeast to climatic extremes, developing a methodology that combines aspects of vulnerability to drought, as well as socioeconomic and climatic indicators used to assess exposure, ability to adaptation and the sensitivity of geographical microregions of the region. The assessment of the susceptibility or degree of exposure to risk is the regional using the SPI (Standardized Precipitation Index) by the degree of magnitude dried (MD), the rate of precipitation such as PCD (Precipitation Concentration Degree) and PCP (Precipitation Period Concentration) helped characterize and regional climatology, these indices showed satisfactory results in the pilot study of Rio Grande do Norte to assess the degree of exposure to drought. Regarding sensitivity agricultural / livestock multivariate statistical technique to factor analysis showed acceptable results for the proposed model using data for the period 1990-1999 (P1). The application of the analysis of vulnerability considering the adaptive capacity, as the adaptive disability have almost similar results with much of the region's vulnerability to extreme south of Bahia state as a part of the semiarid region has a degree of vulnerability among moderate and mean

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Intense precipitation events (IPE) have been causing great social and economic losses in the affected regions. In the Amazon, these events can have serious impacts, primarily for populations living on the margins of its countless rivers, because when water levels are elevated, floods and/or inundations are generally observed. Thus, the main objective of this research is to study IPE, through Extreme Value Theory (EVT), to estimate return periods of these events and identify regions of the Brazilian Amazon where IPE have the largest values. The study was performed using daily rainfall data of the hydrometeorological network managed by the National Water Agency (Agência Nacional de Água) and the Meteorological Data Bank for Education and Research (Banco de Dados Meteorológicos para Ensino e Pesquisa) of the National Institute of Meteorology (Instituto Nacional de Meteorologia), covering the period 1983-2012. First, homogeneous rainfall regions were determined through cluster analysis, using the hierarchical agglomerative Ward method. Then synthetic series to represent the homogeneous regions were created. Next EVT, was applied in these series, through Generalized Extreme Value (GEV) and the Generalized Pareto Distribution (GPD). The goodness of fit of these distributions were evaluated by the application of the Kolmogorov-Smirnov test, which compares the cumulated empirical distributions with the theoretical ones. Finally, the composition technique was used to characterize the prevailing atmospheric patterns for the occurrence of IPE. The results suggest that the Brazilian Amazon has six pluvial homogeneous regions. It is expected more severe IPE to occur in the south and in the Amazon coast. More intense rainfall events are expected during the rainy or transitions seasons of each sub-region, with total daily precipitation of 146.1, 143.1 and 109.4 mm (GEV) and 201.6, 209.5 and 152.4 mm (GPD), at least once year, in the south, in the coast and in the northwest of the Brazilian Amazon, respectively. For the south Amazonia, the composition analysis revealed that IPE are associated with the configuration and formation of the South Atlantic Convergence Zone. Along the coast, intense precipitation events are associated with mesoscale systems, such Squall Lines. In Northwest Amazonia IPE are apparently associated with the Intertropical Convergence Zone and/or local convection.

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Salivary gland neoplasms exhibit a wide variety of biological behavior and a high morphological diversity raises the interest in researching these lesions. The stem cells are the main source for the generation and maintenance of cell diversity, disorders in the regulation of these cells can lead to the production of altered stem cells, termed cancer stem cells capable of generate the tumor. Researches on cancer stem cells and associated proteins have been developed in some oral cancers; however, their role in salivary gland neoplasms is not well established. Thus, the aim of this study was to identify the tumor parenchyma cells exhibiting stem cell characteristics, by evaluating the immunoreactivity of OCT4 and CD44, in a number of cases of salivary gland neoplasms. The sample consisted of 20 pleomorphic adenomas, 20 mucoepidermoid carcinomas and 20 adenoid cystic carcinoma located in minor and major salivary glands. The expression of OCT4 and CD44 was evaluated by the percentage of positive cells (PP) and the intensity of expression (IE), it is realized the sum of the scores, resulting in the total score immunostaining (PIT) ranging 0-7. All studied cases showed positive expression of OCT4 and CD44 and higher values than the control groups. It was observed that for OCT4 luminal cells and non-luminal were immunostained in the case of pleomorphic adenomas and adenoid cystic carcinoma. Already the immunoreactivity of CD44 was particularly evident in the non-luminal cells of these lesions. In mucoepidermoid carcinomas for both markers, there was immunoreactivity in squamous and intermediate cells and absence of staining mucous cells. For both markers, a statistically significant higher immunostaining was verified in neoplasms located in the major salivary glands compared with lesions in the minor salivary (p<0.001). At the total sample and in the group of minor salivary glands, malignant neoplasms exhibited higher immunoreactivity for OCT4 than pleomorphic adenoma. However, there was no statistically significant difference between the lesions and between their classifications histomorphologic. Analyzing the correlation between OCT4 and CD44 immunoexpressions, a statistically significant moderate positive correlation (r = 0.444) was observed. The high expression of OCT4 and CD44 may indicate that these proteins play an important role in identifying cancer stem cells, allowing a prediction of biological behavior of salivary gland neoplasms.

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O presente trabalho constitui uma investigação levada a cabo no âmbito do Mestrado e Ensino do 1.º e 2.º Ciclos de Educação Básica. A problemática surgiu no decorrer da minha prática pedagógica no seio de uma turma do 6.º ano, numa Escola Básica do centro do país. Partindo da necessidade da tomada de posição perante o ensino e a sua finalidade, centra-se na perspetiva de que além da promoção de aquisição de informação, conteúdo e experiência Matemática, também é finalidade do ensino desta disciplina o desenvolvimento de atitudes positivas face à mesma e a capacidade de apreciar esta ciência. Pretende verificar o efeito de um trabalho de projeto nas atitudes dos alunos, pois conhecer apenas a atitude que apresentam em relação à matemática não previne que a mesma evolua no sentido negativo ao longo da escolaridade obrigatória. O projeto realizado na turma teve como dinâmica o trabalho de grupo, no qual os alunos desempenharam o papel de produtores e de consumidores de informação estatística. Avalia a atitude dos alunos em três momentos da concretização do projeto – antes, durante e depois; por forma a evidenciar semelhanças e diferenças nos três momentos, bem como o que poderá ter influenciado o resultado obtido. Considerando a atitude com base em três componentes principais – afetiva, cognitiva e comportamental, a análise dos dados traduziu-se na análise das expressões de comportamento verbal e não-verbal a partir da qual foi inferida a componente de atitude refletida. Os resultados obtidos apontam para uma melhoria nas atitudes dos alunos mediante a metodologia utilizada, nomeadamente no que respeita à apreciação desta ciência através da compreensão da sua aplicabilidade no quotidiano diário e futuro profissional, bem como ao autoconhecimento das suas competências em relação ao tema matemático abordado. Poderia ter tido uma influência mais positiva nas atitudes dos alunos, nomeadamente na componente comportamental, se estes já tivessem desenvolvido competências intrínsecas ao trabalho cooperativo.

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Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model

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The present paper has the purpose of investigate the dynamics of the volatility structure in the shrimp prices in the Brazilian fish market. Therefore, a description of the initial aspects of the shrimp price series was made. From this information, statistics tests were made and selected univariate models to be price predictors. Then, it was verified the existence of relationship of long-term equilibrium between the Brazilian and American imported shrimp and if, confirmed the relationship, whether or not there is a causal link between these assets, considering that the two countries had presented trade relations over the years. It is presented as an exploratory research of applied nature with quantitative approach. The database was collected through direct contact with the Companhia de Entrepostos e Armazéns Gerais de São Paulo (CEAGESP) and on the official website of American import, National Marine Fisheries Service - National Oceanic and Atmospheric Administration (NMFS- NOAA). The results showed that the great variability in the active price is directly related with the gain and loss of the market agents. The price series presents a strong seasonal and biannual effect. The average structure of price of shrimp in the last 12 years was R$ 11.58 and external factors besides the production and marketing (U.S. antidumping, floods and pathologies) strongly affected the prices. Among the tested models for predicting prices of shrimp, four were selected, which through the prediction methodologies of one step forward of horizon 12, proved to be statistically more robust. It was found that there is weak evidence of long-term equilibrium between the Brazilian and American shrimp, where equivalently, was not found a causal link between them. We concluded that the dynamic pricing of commodity shrimp is strongly influenced by external productive factors and that these phenomena cause seasonal effects in the prices. There is no relationship of long-term stability between the Brazilian and American shrimp prices, but it is known that Brazil imports USA production inputs, which somehow shows some dependence productive. To the market agents, the risk of interferences of the external prices cointegrated to Brazilian is practically inexistent. Through statistical modeling is possible to minimize the risk and uncertainty embedded in the fish market, thus, the sales and marketing strategies for the Brazilian shrimp can be consolidated and widespread

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Result of a professional master course of research work in Teaching Science and Technology of the Federal Technological University of Paraná (UTFPR), this work aims to provide the mathematics teacher of the final years of elementary school a teaching sequence (SE) which includes basic content of Statistics provided in the curriculum. In this book a text about the importance of the teaching of statistics is presented, as well as issues related to literacy skills, reasoning and statistical thinking. The development of the SE was designed considering the presuppositions of contextualization, being structured in six steps. We chose to develop a work with the basic contents of Statistics through real data collected with the participation of students, within a context for them significant. This option was due to be possible to develop with the students situations such as: raising hypotheses , communication situations experienced by different graphs and tables , results of discussion and understanding of the significance of the results obtained by means of statistical calculations. Thus, it is believed to be possible to contribute to the development of statistical skills by the students.

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Vivemos na era mais mensurável da história. Na era do petabyte (1000 terabytes) o desafio não é mais o armazenamento de dados, é dar-lhes sentido. Sendo esta a era da revolução dos dados, a respetiva análise torna-se parte integrante de várias ciências. Por exemplo, a biologia molecular deixa de ser uma ciência onde os biólogos estudam um gene de cada vez, para passar a produzir milhares (agora milhões) de medições por amostra para analisar. Além disso, ao contrário da análise do ADN, que é estática, a análise da expressão genética é dinâmica, uma vez que nos vários tecidos expressam-se genes diferentes. O geneticista John Craig Venter, sequenciava organismos isolados, mas com o aparecimento de novas tecnologias e computadores com elevada capacidade de memória, que permitem a análise de dados bastante complexos, passou a estudar ecossistemas inteiros: sequenciação dos microorganismos do oceano, desde 2003, e do ar, desde 2005. A complexidade dos dados é ainda potenciada pelas novas tecnologias que, ao surgirem, são ainda pouco exploradas, produzindo dados com mais ruído dos que as anteriores. Esta complexidade e grau de variabilidade fazem com que a estatística seja um importante e inequívoco contributo na análise. Na realidade, o papel da estatística na biologia molecular vai além de uma mera intervenção. Trata-se de um pilar indissociável desta ciência! A estatística tem vindo a conquistar o seu espaço nesta nova área, tornando-se uma componente essencial de mérito reconhecido.

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This work presents the use of projects as an alternative for teaching statistics, for that it was elaborated a Project that involves the educational socioeconomic reality from the families of the students and built a link between the reality and the scholastic knowledge. This project was applied in Sesi School - Pato Branco between the months of August to September 2014 with 25 students from the 1o and 2o grades from High School. To work the statistics concepts a questionnaire was applied for the parents of the students of the Project´s, they answer it and through these answers the students made frequency tables and graphs, besides measure calculations on measures of central tendency and dispersion measure. All of the construction were realized manually and in the Excel spreadsheet and some of them were chosen to be in this work to with the purpose of showing the hits and the mistakes done. The students worked in groups of 5 students, except in the last class when it was done a test referring to the contents taught in the classroom and a questionnaire for them to evaluate the project´s application. The results show that the teaching of Statistics trough projects motivate the students interest, stimulating the statistical reasoning, in addition made the students know a Math that was different from the one they have already known, with a lot of calculation but with no final objective.

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"[…]. A aplicação de técnicas estatísticas na análise de problemas económicos, em que é necessário testar hipóteses sobre as relações económicas e prever mudanças nos valores de variáveis relevantes, tem tido uma importância crescente. Algumas relações teóricas entre variáveis económicas podem ser expressas usando modelos matemáticos, cujos parâmetros podem ser estimados usando métodos estatísticos. […].Os gestores de empresas são frequentemente confrontados com processos de tomada de decisão, pelo que a posse de conhecimentos de Estatística e o domínio de software que permita a gestão de informação em tempo real é uma mais-valia, principalmente na análise de situações que incluam cenários de incerteza. Nessa perspetiva, os gestores e todos os outros tomadores de decisão têm de ser capazes de entender a informação e usá-la eficazmente, não esquecendo que “se gerir é tomar decisões, gerir bem é tomar boas decisões".

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Currently, the decision analysis in production processes involves a level of detail, in which the problem is subdivided to analyze it in terms of different and conflicting points of view. The multi-criteria analysis has been an important tool that helps assertive decisions related to the production process. This process of analysis has been incorporated into various areas of production engineering, by applying multi-criteria methods in solving the problems of the productive sector. This research presents a statistical study on the use of multi-criteria methods in the areas of Production Engineering, where 935 papers were filtered from 20.663 publications in scientific journals, considering a level of the publication quality based on the impact factor published by the JCR between 2010 and 2015. In this work, the descriptive statistics is used to represent some information and statistical analysis on the volume of applications methods. Relevant results were found with respect to the "amount of advanced methods that are being applied and in which areas related to Production Engineering." This information may provide support to researchers when preparing a multi-criteria application, whereupon it will be possible to check in which issues and how often the other authors have used multi-criteria methods.

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"A Estatística tem um papel relevante a nível da investigação científica na área das Ciências da Saúde, uma vez que as práticas e as investigações médicas geram uma grande quantidade de dados, cheios de incerteza e variabilidade, estando assim as variáveis de interesse sujeitas a flutuações aleatórias […]. A compreensão e a análise crítica de muitos dos artigos publicados no âmbito da saúde, da investigação médica e da epidemiologia requer a posse de conhecimentos estatísticos. […] A posse de conhecimentos estatísticos por parte dos cidadãos, na medida em que lhes possibilita uma melhor capacidade a nível da compreensão e análise crítica das informações disseminadas através dos meios de comunicação social e da literatura, poderá contribuir para que estes tenham um papel mais ativo na sociedade e na promoção de hábitos de vida saudáveis.".

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A triagem consiste numa avaliação preliminar do paciente, a qual deverá ser efetuada rapidamente, em cerca de 60 segundos, e pode ser confiada à equipa paramédica. Esta avaliação tem como principal objectivo determinar se o animal apresenta uma ou várias lesões susceptíveis de comprometer as suas funções vitais. Ao longo deste trabalho, são demonstradas diferentes escalas de triagem, de forma a dar a conhecer diversas formas de abordagem ao paciente crítico. Devido ao facto de existirem cada vez mais pacientes a dar entrada nos serviços de urgência veterinária, cria-se a necessidade de tentar adaptar uma destas escalas a esta realidade, tal como acontece em medicina humana. Uma grande variedade de sistemas, que classificam a gravidade das doenças, têm sido usados nos cuidados intensivos em humanos e sistemas similares têm sido desenvolvidos para unidades de cuidados intensivos de pequenos animais. Deste modo, esta dissertação de mestrado, através de um estudo estatístico, procurou correlacionar diferentes variáveis com a sobrevivência de um grupo de animais, em estado crítico, que deu entrada no Centro Hospitalar Veterinário (CHV).