115 research outputs found

    Cloud-based system for IoT data acquisition

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    IoT permite-nos trazer o mundo físico para o mundo virtual, dando o poder de o controlar e monitorizar. Isto tem encorajado um aumento no interesse em IoT, devido às múltiplas aplicações nos mais variados contextos. Ainda assim sistemas de IoT enfrentam desafios tais como o suporte de altos volume de conexões ou a baixa capacidade de computação face a algoritmos para segurança dos dados. O objectivo desta dissertação é criar um sistema de recolha de dados de sensor de qualidade do ar que resolva esses desafios usando tecnologias de estado de arte, dando preferência a ferramentas de código aberto. O sistema foi implementado em volta Apache Kafka, com Spring Boot e VerneMQ responsáveis por receber dados e PostgreSQL, com plugin Timescale, encarregue de os guardar. Um protótipo do sistema foi implementado usando contentores Docker, mas não foi possível organiza-los com Kubernetes; Abstract: Cloud-based system for IoT data acquisition The purpose of IoT is to bring the physical world into a digital one and allowing it to be controlled and monitored from a virtual standpoint. The interest in IoT has increased due to its many applications in various fields, but IoT systems still deal with challenges such as the support of a high volume of connections or the low processing capacity of devices faced with data security algorithms. The objective of this dissertation is to create a data collection for air quality sensors system, that solves those challenges based on state of the art technologies, giving preference to open-source tools. Implementation was done around Apache Kafka, with Spring Boot and VerneMQ receiving data, HMAC granting a level security on data transport and PostgreSQL with the plugin Timescale storing the data. A prototype of the system was implemented in Docker containers, but we were unable to orchestrate them through Kubernetes

    Efeitos do sistema de gestâo do solo na disponibilidade de N e produtividade de plantações de castanheiro em condições Mediterrâneas

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    Soil tillage with chisel ploughing is the conventional soil management system in chestnut stands for fruit production in Northern Portugal. A study was developed to assess the effects of three soil management systems on in situ soil N mineralization dynamics, tree nutrition status and fruit productivity, in a 50-yr old chestnut stand. The treatments were: conventional tillage with a chisel ploughing twice a year (CT), no-tillage with rainfed improved pasture with leguminous and grasses plants (NIP), and no-tillage with spontaneous herbaceous vegetation - natural pasture (NP). The CT treatment showed a strong increase of the soil N mineral concentration following soil disturbance by tillage, but the cumulative net N mineralized along the year was significantly lower (51.8 kg ha-1) than in the NIP (85.1 kg ha-1) treatment. The NP treatment (65.9 kg ha-1) did not cause a reduction in the soil N mineralization when compared to the CT treatment. The mineralization rate (g mineralized N kg-1 total N) in 2004 was about 26, 30 and 38 in the treatments CT, NP and NIP, respectively. Treatments showed different soil N dynamics, the proportion of mineralized NO3--N being lower in the NP (10-48%) than in CT and NIP treatments (53-74%). Our study indicates that no-tillage systems improve the tree nutrition status and enhance productivit

    MODELING the INTERACTION BETWEEN AIDS and TUBERCULOSIS

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    A deterministic model is proposed for the study of the dynamics of acquired immunodeficiency syndrome (AIDS) and tuberculosis (TB) co-infection. the model is comprised by a set of sixteen ordinary differential equations representing different states of both diseases, and it is intended to provide a theoretical framework for the study of the interaction between both infections. Numerical simulations of the model resulted in three striking outcomes: first, the pathogenicity of Human Immunodeficiency Virus (HIV) is enhanced by the presence of TB, and vice-versa; second, the prevalence of AIDS is higher in the presence of TB; and third, relative risk analysis demonstrated a much stronger influence of AIDS on TB than the other way around.ESCOLA PAULISTA MED,BR-04023 São Paulo,BRAZILUNIV São Paulo,INST PHYS,São Paulo,BRAZILHCFMUSP,BR-01246 São Paulo,BRAZILESCOLA PAULISTA MED,BR-04023 São Paulo,BRAZILWeb of Scienc

    Effects of soil management practices and irrigation on plant water relations and productivity of chestnut stands under Mediterranean conditions

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    The effects of different soil management practices and irrigation on plant water relations, physiological response and productivity of chestnut stands in Northeastern Portugal were assessed during four growing seasons (2003 to 2006). Treatments were: conventional soil tillage up to 15–20 cm depth with a tine cultivator thrice a year (CT); no tillage with spontaneous herbaceous vegetation (NV); no tillage with rainfed seeded pasture (NP); and no tillage with irrigated seeded pasture (NIP). Results suggest that soil water availability was the most critical parameter for chestnut productivity over the study period. In all treatments, high predawn leaf water potentials (-0.40 to -0.55 MPa) were observed during the dry seasons of 2003, 2004 and 2006, showing no critical conditions for plant productivity, which is ascribed to water availability in deep soil layers. In contrast, in 2005, an extremely dry year, water potentials decreased and varied from -1.46 to - 1.72 MPa in late summer, showing unfavourable conditions for nut production. Maintenance of spontaneous herbaceous vegetation without irrigation enhanced productivity of chestnut stands as compared with the conventional tillage system and the no tillage system with seeded pasture. Productivity in the soil watering system (NIP treatment) was not significantly different from that observed in the NV treatment. Therefore, studies on the irrigation strategy should be developed, in order to increase its efficiency especially in stands with young tree

    Displacer-type liquid level sensor with liquid density auto-compensation

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    In the classic displacer-type liquid level measuring method, liquid level is calculated via the buoyancy force exerted by the liquid on a displacer. This technology has high linearity, precision, accuracy, ease of installation and low cost. Nonetheless, displacer level sensors have significant sensitivity to variations in liquid density, which hinder its use in industrial applications that such quantity is not held constant. In this paper a novel displacer-type liquid level sensor is presented and analyzed. The innovation of the new sensor consists of adding another displacer and thus calculating the new measured value by the quotient of the buoyancy forces of both displacers. Therefore, the new measurement is ideally insensitive to the variations in liquid density. A prototype was built and prototype results presented high linearity, being able to mitigate the sensitivity to the liquid density, increasing accuracy in the measurements

    A Pandemia da COVID-19 impactou o ENEM? Uma Análise Comparativa de Dados dos Anos de 2019 e 2020

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    O Ministério da Educação do Brasil avalia o desempenho escolar dos estudantes ao término da educação básica através do Exame Nacional do Ensino Médio (ENEM), o qual é tambémm usado para a entrada dos estudantes no ensino superior. Com a pandemia da COVID-19, muitas escolas tiveram que pausar as aulas ou manter o ensino de forma remota, o que afetou o processo de ensino e aprendizagem. Este artigo objetiva identificar se a pandemia impactou o ENEM, utilizando os microdados do ENEM de 2019, ano anterior ao início da pandemia, e do ENEM de 2020, primeiro ano da pandemia. O estudo realiza uma análise exploratória baseada em mineração de dados para comparar os dados dos dois anos. Os resultados apontam para uma melhoria nas notas médias gerais e aumento da disparidade de notas entre os candidatos de maior e menor renda

    A educação básica nas comunidades ribeirinhas do Estado do Amapá

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    This work aims to examine scientific productions on the quality of education in riverside communities considering the specifics of displacement. And how basic education has been addressed in riverside communities in the state of Amapá, in scientific production. Methodologically, the work used bibliographical research, through a literature review on the theme Education for riverside communities and ending with the result that education in riverside communities needs infrastructure in schools in Amapá with expansion, adaptation and reforms. Continuing education for teachers and a permanent staff at the school for all professionals, safe school transport and a curriculum focused on student knowledge and culture for the full development of citizenship.O referido trabalho tem objetivo de examinar as produções científicas sobre a qualidade da educação nas comunidades ribeirinhas considerando as especificidades do deslocamento. E de que forma a educação básica vem sendo abordada nas comunidades ribeirinhas do estado do Amapá, nas produções científicas.  Metodologicamente, o trabalho utilizou a pesquisa bibliográfica, através da revisão de literatura acerca da temática Educação para as comunidades ribeirinhas e finalizando com o resultado de que a educação nas comunidades ribeirinhas necessita de infraestrutura nas escolas amapaenses com ampliação, adequação e reformas. Formação continuada para os professores e um quadro fixo na escola de todos os profissionais, transporte escolar seguro e um currículo voltado para o saber e cultura do aluno para desenvolvimento pleno da cidadania

    Análisis fitoquímico, actividad antibacteriana y acción moduladora de antibióticos de Jatropha mollissima (Pohl.) Baill. (Euphorbia­ceae)

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    The emergence of resistant bacterial strains and the significant increase in side effects of currently available antibacterial drugs have made it urgent to develop research to identify new bioactives antibacterial compounds. Jatropha mollissima is a plant endemic to the Caatinga biome, Brazil and this species has antioxidant, antibacterial and antiproliferative action. The present study aimed to evaluate the antibacterial and modulatory potentials of J. mollissima against multiresistant bacterial strains. The phytochemical profile was obtained from gas chromatography coupled to mass spectrometry. J. mollissima presented moderate antibacterial activity and modulated the activity of the antibiotic Norfloxacin, promoting an antagonistic relationship. This was the first study of this nature carried out with J. mollissima.La aparición de cepas bacterianas resistentes y los efectos secundarios de sus fármacos disponibles han hecho investigar nuevos compuestos antibacterianos bioactivos. Jatropha mollissima es una planta endémica del bioma Caatinga, Brasil. Existen informes en la literatura de que esta especie tiene acción antioxidante, antibacteriana y antiproliferativa. El presente estudio tuvo como objetivo evaluar el potencial antibacteriano y modulador de J. mollissima contra cepas bacterianas multirresistentes. El perfil fitoquímico se obtuvo por cromatografía de gases junto con espectrometría de masas. J. mollissima mostró actividad antibacteriana moderada y moduló la actividad del antibiótico Norfloxacino, promoviendo una relación antagonista. Este fue el primer estudio de este tipo realizado con J. mollissima
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