Análise estrutural não linear pelo metodo dos elementos finitos utilizando-se relaxação viscosa acelerada

Neste trabalho discute-se a utilizacfio da técnica de relaxacáo viscosa para a solucao de equacoes do método dos elementos finitos, visando-se a sua implementacao em computadores de processamento paralelo/vetorial. Os problemas de convergencia e número de iteracoes foram minimizados de modo a obter-se um algoritmo seguro e versátil, que oferece as seguintes vantagens: simplicidades de implementacáo , reduzida memória central e facilidade de refinamento e modificacóes da malha. Sfio apresentados estudos relativos a dois casos clássicos de leitura, tanto em regime linear quanto elástico plástico.This paper discusses the implementation of the accelerated viscous relaxation technique to be used in nonlinear finite element analysis on vector/parallel computers. The resulted approach have significant advantages: reduced central storage, great efficiency and the suitability for adaptative finite element analysis. Two classic elasto-plastic cases are studied and the obtained performance are examined for the linear and nonlinear ranges. 1s the authors opinion that the generated software can be considered as an engineering tool to treat complex problems with economy and versatility.Peer Reviewe

Sentiment analysis domain based environment

In this article, the Sentiment Analysis, which main task is to understand the polarity of the opinions expressed in the documents, is used to obtain a better understanding of how people express themselves about a particular subject or domain. Such understanding is important because it may provide input in the formulation of policies and actions to be taken in relation to a product or service or to the perceptions related to issues or people. As more people put their thoughts and opinions on a variety of services available on the Web microblogging sites like Twitter, social networks and forums have become a common way for them to express themselves. There, they put in a spontaneous, free and in real time over different views on the issues. However, each domain or Internet service has its own peculiarities. Some jargon is specific to a domain. Certain slang or characteristics of services for people putting their opinions differ significantly, which undermines the use of machine learning systems previously developed for other domains. To validate the proposed methodology a corpus of nuclear texts was assembled, annotated and analyzed. After that, a system was developed to process these data. The results thus obtained provide important information on the identification of key stakeholders and the views expressed on what subjects. With this better understanding of the fears, prejudices and expectations of people regarding the nuclear area, new strategies can be traced to improve the perception of them as the nuclear area

Análise estrutural não linear pelo metodo dos elementos finitos utilizando-se relaxação viscosa acelerada

Neste trabalho discute-se a utilizacfio da técnica de relaxacáo viscosa para a solucao de equacoes do método dos elementos finitos, visando-se a sua implementacao em computadores de processamento paralelo/vetorial. Os problemas de convergencia e número de iteracoes foram minimizados de modo a obter-se um algoritmo seguro e versátil, que oferece as seguintes vantagens: simplicidades de implementacáo , reduzida memória central e facilidade de refinamento e modificacóes da malha. Sfio apresentados estudos relativos a dois casos clássicos de leitura, tanto em regime linear quanto elástico plástico.This paper discusses the implementation of the accelerated viscous relaxation technique to be used in nonlinear finite element analysis on vector/parallel computers. The resulted approach have significant advantages: reduced central storage, great efficiency and the suitability for adaptative finite element analysis. Two classic elasto-plastic cases are studied and the obtained performance are examined for the linear and nonlinear ranges. 1s the authors opinion that the generated software can be considered as an engineering tool to treat complex problems with economy and versatility.Peer Reviewe

Processo semi-analítico para análise de estruturas pelo método dos elementos finitos

Static linear analysis is applied to three dimensional problems through the semi-analytical finite element process, making use of orthogonal functions. Prismatic structures and axi-symmetric structures with non-symmetrical loads, are studied using two finite elements. The first is a isoparametric quadrilateral quadratic element for solid bodies and the other, a degenerated superparametric cubic element, indicated for shells. A computer program employing this elements was prepared. Some examples are presented using the above program and the results discussed with those from available analytica solutions.A análise linear, estática de problemas tridimensionais é efetuada pelo processo semi-analítico, utilizando-se funções ortogonais. Estruturas prismáticas e axissimétricas com carregamento qualquer, são resolvidas com o implemento de dois elementos finitos. O primeiro, isoparamétrico quadrilátero quadrático, para o estudo de sólidos e, o outro, degenerado superparamétrico cúbico, especialmente indicado para o caso de cascas. Um programa automático utilizando os elementos desenvolvidos é elaborado. Alguns exemplos são apresentados, com o uso deste programa e, os resultados, comparados com as soluções analíticas são discutidos

Data mining for environmental analysis and diagnostic: a case study of upwelling ecosystem of Arraial do Cabo

The Brazilian coastal zone presents a large extension and a variety of environments. Nevertheless, little is known about biological diversity and ecosystem dynamics. Environmental changes always occur; however, it is important to distinguish natural from anthropic variability. Under these scenarios, the aim of this work is to present a Data Mining methodology able to access the quality and health levels of the environmental conditions through the biological integrity concept. A ten-year time series of physical, chemical and biological parameters from an influenced upwelling area of Arraial do Cabo-RJ were used to generate a classification model based on association rules. The model recognizes seven different classes of water based on biological diversity and a new trophic index (PLIX). Artificial neural networks were evolved and optimized by genetic algorithms to forecast these indices, enabling environmental diagnostic to be made taking into account control mechanisms of topology, stability and complex behavioral properties of food web.A zona costeira brasileira apresenta grande extensão e variedade de ambientes. Contudo, pouco se sabe sobre sua diversidade biológica e o funcionamento dos ecossistemas. Como mudanças ambientais são constantes, é muito importante distinguir entre variabilidade natural e antrópica. Nesse cenário, o objetivo deste trabalho é apresentar a metodologia para o desenvolvimento de um Sistema Inteligente de Gerenciamento Integrado do Ecossistema Costeiro (SIGIEC) capaz de acessar o nível de qualidade e saúde ambiental através do conceito de Integridade Biológica. Foram usadas séries temporais de dez anos de parâmetros físicos, químicos e biológicos para extrair conhecimento e gerar modelos de regras de associação para classificar sete diferentes tipos de condições ambientais, analisadas através da diversidade biológica e um novo índice trófico (PLIX). Redes neurais artificiais foram otimizadas por algoritmos genéticos para fazer predições desses índices e apresenta-se um diagnóstico ambiental baseado na análise dos mecanismos de controle da topologia, estabilidade e propriedades do comportamento complexo de redes alimentares

Data Mining on Parallel Database Systems

Abstract Recent years have shown the need of an automated process to discover interesting and hidden patterns in real-world databases, handling large volumes of data. This sort of process implies a lot of computational power, memory and disk I/O, which can only be provided byparallel computers. Our work contributes with a solution that integrates a machine learning algorithm, parallelism and a tightly-coupled use of a DBMS system, addressing performance problems with parallel processing and data fragmentation