63 research outputs found

    Arquitectura para um registador de dados

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    A aquisição de dados é um procedimento utilizado em várias áreas. O presente trabalho tem como objectivo desenvolver um registador que armazena dados obtidos de uma ou mais fontes. Para esse efeito propõe-se uma arquitectura baseada num computador pessoal cujas dimensões e interface de expansão obedecem à norma industrial PC/104. Foi desenvolvida uma placa de aquisição para esta interface e foi utilizado o Linux como sistema operativo. Para cumprir os requisitos de tempo real do sistema utilizou-se o Real Time Linux, que corre o Linux como uma tarefa de baixa prioridade, permitindo usufruir de todos os seus serviços e funcionalidades. A aplicação que gere o registador e a interface de configuração foi programada em linguagem Java. Esta aplicação comunica com um módulo desenvolvido no espaço do Real Time Linux para efectuar o ciclo de aquisição, em determinados intervalos temporais pré-programados. Do ponto de vista do utilizador, a arquitectura interna do sistema tem por orientação as normas industriais existentes para instrumentos programáveis. A configuração do registador é efectuada remotamente via TCP/IP. Adicionalmente, e seguindo a tendência que existe para este tipo de aplicações, foram desenvolvidos gestores de dispositivo para a utilização com o programa LabVIEW.info:eu-repo/semantics/publishedVersio

    Registador de dados para aplicações de baixo consumo

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    Este artigo descreve uma arquitectura de um registador de dados para aplicações de baixo consumo. São apresentados resultados experimentais sobre o desempenho do oscilador, que é um dos módulos do registador. São ainda apresentadas estimativas do consumo do registador e dos respectivos módulos. A autonomia e a estabilidade são os critérios de projecto mais relevantes de um registador de dados para aplicações de baixo consumo que exijam precisão temporal, por exemplo a sismologia oceânica.info:eu-repo/semantics/publishedVersio

    A Comparative Analysis of Load Balancing Algorithms Applied to a Weather Forecast Model

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    Among the many reasons for load imbalance in weather forecasting models, the dynamic imbalance caused by lo-calized variations on the state of the atmosphere is the hard-est one to handle. As an example, active thunderstorms may substantially increase load at a certain timestep with re-spect to previous timesteps in an unpredictable manner – after all, tracking storms is one of the reasons for running a weather forecasting model. In this paper, we present a com-parative analysis of different load balancing algorithms to deal with this kind of load imbalance. We analyze the im-pact of these strategies on computation and communication and the effects caused by the frequency at which the load balancer is invoked on execution time. This is done with-out any code modification, employing the concept of proces-sor virtualization, which basically means that the domain is over-decomposed and the unit of rebalance is a sub-domain. With this approach, we were able to reduce the execution time of a full, real-world weather model. 1

    The Brazilian Developments On The Regional Atmospheric Modeling System (brams 5.2): An Integrated Environmental Model Tuned For Tropical Areas

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We present a new version of the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS), in which different previous versions for weather, chemistry, and carbon cycle were unified in a single integrated modeling system software. This new version also has a new set of state-of-the-art physical parameterizations and greater computational parallel and memory usage efficiency. The description of the main model features includes several examples illustrating the quality of the transport scheme for scalars, radiative fluxes on surface, and model simulation of rainfall systems over South America at different spatial resolutions using a scale aware convective parameterization. Additionally, the simulation of the diurnal cycle of the convection and carbon dioxide concentration over the Amazon Basin, as well as carbon dioxide fluxes from biogenic processes over a large portion of South America, are shown. Atmospheric chemistry examples show the model performance in simulating near-surface carbon monoxide and ozone in the Amazon Basin and the megacity of Rio de Janeiro. For tracer transport and dispersion, the model capabilities to simulate the volcanic ash 3-D redistribution associated with the eruption of a Chilean volcano are demonstrated. The gain of computational efficiency is described in some detail. BRAMS has been applied for research and operational forecasting mainly in South America. Model results from the operational weather forecast of BRAMS on 5km grid spacing in the Center for Weather Forecasting and Climate Studies, INPE/Brazil, since 2013 are used to quantify the model skill of near-surface variables and rainfall. The scores show the reliability of BRAMS for the tropical and subtropical areas of South America. Requirements for keeping this modeling system competitive regarding both its functionalities and skills are discussed. Finally, we highlight the relevant contribution of this work to building a South American community of model developers. © Author(s) 2017.1011892222014/01563-1, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2014/01564-8, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2015/10206-0, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo306340/2011-9, Conselho Nacional de Desenvolvimento Científico e TecnológicoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Evaluation of commercial soy sauce koji strains of Aspergillus oryzae for γ-aminobutyric acid (GABA) production

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    In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P < 0.05) among themselves. Based on the A. oryzae strains, highest GABA concentration was obtained from NSK (194 mg/L) followed by NSZ (63 mg/L), NSJ (51.53 mg/L) and NST (31.66 mg/L). Therefore, A. oryzae NSK was characterized and the sequence was found to be similar to A. oryzae and A. flavus with 99 % similarity. The evolutionary distance (K nuc) between sequences of identical fungal species was calculated and a phylogenetic tree prepared from the K nuc data showed that the isolate belonged to the A. oryzae species. This finding may allow the development of GABA-rich ingredients using A. oryzae NSK as a starter culture for soy sauce production
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