18 research outputs found

    BIGhybrid - A Toolkit for Simulating MapReduce on Hybrid Infrastructures

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    Cloud computing has increasingly been used as a platform for running large business and data processing applications. Although clouds have become highly popular, when it comes to data processing, the cost of usage is not negligible. Conversely, Desktop Grids, have been used by a plethora of projects, taking advantage of the high number of resources provided for free by volunteers. Merging cloud computing and desktop grids into hybrid infrastructure can provide a feasible low-cost solution for big data analysis. Although frameworks like MapReduce have been conceived to exploit commodity hardware, their use on hybrid infrastructure poses some challenges due to large resource heterogeneity and high churn rate. This study introduces BIGhybrid a toolkit to simulate MapReduce on hybrid environments. The main goal is to provide a framework for developers and system designers to address the issues of hybrid MapReduce. In this paper, we describe the framework which simulates the assembly of two existing middleware: BitDew- MapReduce for Desktop Grids and Hadoop-BlobSeer for Cloud Computing. Experimental results included in this work demonstrate the feasibility of our approach

    Docência na Atualidade Brasileira: rastreando controvérsias acerca do movimento Escola Sem Partido

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    O movimento Escola sem Partido (ESP) teve sua origem por meio da veiculação de um site em 2004, porém, assumiu ampla visibilidade somente no ano de 2014 com os projetos de lei que passaram a tramitar no Congresso Nacional em sintonia com a respectiva temática. Em nome da defesa da liberdade de expressão, lideranças do ESP argumentam que o ensino deveria ser realizado exclusivamente com o objetivo da produção e difusão de conhecimento. Para tal, defendem a neutralidade nesse processo, argumentando pela abertura às diferentes abordagens investigativas e justificando seus posicionamentos com um suposto cenário da educação brasileira, onde um significativo número de docentes dotados de concepções políticas agiria com intenções de doutrinação dos seus discentes. O ESP divulga, em seu site, os diversos projetos de lei que tramitam pelo país com a respectiva temática. Tais projetos demonstram a abrangência do movimento na medida em que circulam nas dimensões federal, estadual e municipal. Parece que a atualidade da educação brasileira e, mais precisamente, os próprios contornos da docência, vivem momentos de intensa controvérsia. Qual seria o papel do professor na educação do país? Vemos controvérsias que circulam em um cenário que mistura mediadores diversos. Articulam-se a política, os professores, a grande mídia, pesquisas, alunos, o direito dentre outros. A fronteira da docência parece ser uma questão atual a ser respondida e definida por tal coletivo. O presente artigo, portanto, objetiva desenvolver uma cartografia descritiva da produção dos contornos daquilo que se entende por docência na atualidade brasileira. Busca-se evidenciar as redes heterogêneas de mediações que a produzem

    Boosting big data streaming applications in clouds with burstFlow

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    The rapid growth of stream applications in financial markets, health care, education, social media, and sensor networks represents a remarkable milestone for data processing and analytic in recent years, leading to new challenges to handle Big Data in real-time. Traditionally, a single cloud infrastructure often holds the deployment of Stream Processing applications because it has extensive and adaptative virtual computing resources. Hence, data sources send data from distant and different locations of the cloud infrastructure, increasing the application latency. The cloud infrastructure may be geographically distributed and it requires to run a set of frameworks to handle communication. These frameworks often comprise a Message Queue System and a Stream Processing Framework. The frameworks explore Multi-Cloud deploying each service in a different cloud and communication via high latency network links. This creates challenges to meet real-time application requirements because the data streams have different and unpredictable latencies forcing cloud providers' communication systems to adjust to the environment changes continually. Previous works explore static micro-batch demonstrating its potential to overcome communication issues. This paper introduces BurstFlow, a tool for enhancing communication across data sources located at the edges of the Internet and Big Data Stream Processing applications located in cloud infrastructures. BurstFlow introduces a strategy for adjusting the micro-batch sizes dynamically according to the time required for communication and computation. BurstFlow also presents an adaptive data partition policy for distributing incoming streams across available machines by considering memory and CPU capacities. The experiments use a real-world multi-cloud deployment showing that BurstFlow can reduce the execution time up to 77% when compared to the state-of-the-art solutions, improving CPU efficiency by up to 49%

    Proposta de métricas de avaliação da qualidade da informação médica para Sistemas de Recomendação baseados no perfil do usuário

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    A Web é uma fonte de busca onde as pessoas procuram informações sobre cuidados em saúde. Entretanto, é aberta a vários tipos de publicação e provedores de informação, portanto a qualidade das informações em saúde que são publicadas são altamente variáveis e dinâmicas.  Um usuário leigo que busca informação nem sempre possui o conhecimento e educação suficientes para avaliar e validar a informação disponível. Neste relatório aborda-se um sistema de recomendação baseado no perfil do usuário e na qualidade da informação recomendada

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    MRSG : a MapReduce simulator for desktop grids

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    This technical report presents the MRSG simulator for MapReduce platforms. The simulator’s goal is to serve as a research tool, and assist in the development of new approaches and solutions to MapReduce platforms. It is described, as well, the decisions made in the simulator’s model, MRSG’s architecture, and the current development state. An initial validation shows the current precision of the already implemented features, in comparison to real executions of the Hadoop MapReduce platform

    Adequacy of intensive data computing to desktop grid environment with using of mapreduce

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    O surgimento de volumes de dados na ordem de petabytes cria a necessidade de desenvolver-se novas soluções que viabilizem o tratamento dos dados através do uso de sistemas de computação intensiva, como o MapReduce. O MapReduce é um framework de programação que apresenta duas funções: uma de mapeamento, chamada Map, e outra de redução, chamada Reduce, aplicadas a uma determinada entrada de dados. Este modelo de programação é utilizado geralmente em grandes clusters e suas tarefas Map ou Reduce são normalmente independentes entre si. O programador é abstraído do processo de paralelização como divisão e distribuição de dados, tolerância a falhas, persistência de dados e distribuição de tarefas. A motivação deste trabalho é aplicar o modelo de computação intensiva do MapReduce com grande volume de dados para uso em ambientes desktop grid. O objetivo então é investigar os algoritmos do MapReduce para adequar a computação intensiva aos ambientes heterogêneos. O trabalho endereça o problema da heterogeneidade de recursos, não tratando neste momento a volatilidade das máquinas. Devido às deficiências encontradas no MapReduce em ambientes heterogêneos foi proposto o MR-A++, que é um MapReduce com algoritmos adequados ao ambiente heterogêneo. O modelo do MR-A++ cria uma tarefa de medição para coletar informações, antes de ocorrer a distribuição dos dados. Assim, as informações serão utilizadas para gerenciar o sistema. Para avaliar os algoritmos alterados foi empregada a Análise 2k Fatorial e foram executadas simulações com o simulador MRSG. O simulador MRSG foi construído para o estudo de ambientes (homogêneos e heterogêneos) em larga escala com uso do MapReduce. O pequeno atraso introduzido na fase de setup da computação é compensado com a adequação do ambiente heterogêneo à capacidade computacional das máquinas, com ganhos de redução de tempo de execução dos jobs superiores a 70 % em alguns casos.The emergence of data volumes in the order of petabytes creates the need to develop new solutions that make possible the processing of data through the use of intensive computing systems, as MapReduce. MapReduce is a programming framework that has two functions: one called Map, mapping, and another reducing called Reduce, applied to a particular data entry. This programming model is used primarily in large clusters and their tasks are normally independent. The programmer is abstracted from the parallelization process such as division and data distribution, fault tolerance, data persistence and distribution of tasks. The motivation of this work is to apply the intensive computation model of MapReduce with large volume of data in desktop grid environments. The goal then is to investigate the intensive computing in heterogeneous environments with use MapReduce model. First the problem of resource heterogeneity is solved, not treating the moment of the volatility. Due to deficiencies of the MapReduce model in heterogeneous environments it was proposed the MR-A++; a MapReduce with algorithms adequated to heterogeneous environments. The MR-A++ model creates a training task to gather information prior to the distribution of data. Therefore the information will be used to manager the system. To evaluate the algorithms change it was employed a 2k Factorial analysis and simulations with the simulant MRSG built for the study of environments (homogeneous and heterogeneous) large-scale use of MapReduce. The small delay introduced in phase of setup of computing compensates with the adequacy of heterogeneous environment to computational capacity of the machines, with gains in the run-time reduction of jobs exceeding 70% in some cases
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