3,855 research outputs found
Towards a knowledge-based system to assist the Brazilian data-collecting system operation
A study is reported which was carried out to show how a knowledge-based approach would lead to a flexible tool to assist the operation task in a satellite-based environmental data collection system. Some characteristics of a hypothesized system comprised of a satellite and a network of Interrogable Data Collecting Platforms (IDCPs) are pointed out. The Knowledge-Based Planning Assistant System (KBPAS) and some aspects about how knowledge is organized in the IDCP's domain are briefly described
The effect of temperature on the dynamics of a homogeneous oscillatory system operated in batch and under flow
The effect of temperature on a network of chemical reactions is not obvious, especially when compared to the effect exerted on elementary steps. There are few reports regarding the estimation of parameters such as activation energies for oscillating chemical systems. Still less investigated is the importance of the relative distance from thermodynamic equilibrium on the way in which temperature influences the oscillators' dynamics – a crucial aspect for the understanding of chemical and bio-chemical oscillating networks. In this paper we use the bromate–oxalic acid–acetone–cerium oscillatory system to study the influence of temperature under close and far-from-equilibrium regimes. The research was carried out under identical conditions for batch and flow (in a continuous flow stirred tank reactor, CSTR) regimes, and the main oscillation features were preserved, so that it was possible to isolate the effect of flow. Overall, increasing the flow results in an increase of the oscillatory frequency. The apparent oscillatory activation energy was found to decrease from 72 ± 6 kJ mol−1, for the system operated in batch, to 50 ± 2 kJ mol−1, under the flow regime. The role of the distance from the thermodynamic equilibrium on the temperature dependence is generalized and discussed in connection with other systems. Numerical simulations using the Brusselator model under batch and flow regimes further helped the discussion of the main experimental results
The new automated daily mortality surveillance system
The experience reported in an earlier Eurosurveillance issue on a fast method to evaluate the impact of the 2003 heatwave on mortality in Portugal, generated a daily mortality surveillance system (VDM) that has been operating ever since jointly with the Portuguese Heat Health Watch Warning System. This work describes the VDM system and how it evolved to become an automated system operating year-round, and shows briefly its potential using mortality data from January 2006 to June 2009 collected by the system itself. The new system has important advantages such as: rapid information acquisition, completeness (the entire population is included), lightness (very little information is exchanged, date of death, age, sex, place of death registration). It allows rapid detection of impacts (within five days) and allows a quick preliminary quantification of impacts that usually took several years to be done. These characteristics make this system a powerful tool for public health action. The VDM system also represents an example of inter-institutional cooperation, bringing together organisations from two different ministries, Health and Justice, aiming at improving knowledge about the mortality in the population
Os sistemas de controlo de gestão nas empresas de setores tradicionais na região de Trás-os-Montes
A criação/desenvolvimento de empresas é frequentemente apontada como uma estratégia viável para o desenvolvimento das regiões. Para este fim, as empresas dispõem de vários instrumentos entre os quais os SCG – Sistemas de Controlo de Gestão. Estes são considerados como importantes instrumentos para o crescimento e desenvolvimento das empresas incluindo PME.
Assim, pretende-se com o presente trabalho avaliar o sistema de controlo de gestão existente nas empresas dos setores de atividade tradicionais da região de Trás-os-Montes. Para o efeito, após uma revisão da literatura, procede-se a um estudo empírico com base em dados primários de uma amostra de 7 empresas, recorrendo ao questionário com 3 grupos de questões.
Os resultados vão de encontro ao esperado, ou seja, nem todas as empresas possuem SCG e as que não possuem não tencionam implementar esse sistema no curto prazo. Verifica-se alguma indiferença, relativamente à performance das empresas que possuem SCG
Fire and flooding resilience in Mimosa L. of the Brazilian Pantanal
PosterThe Pantanal ecoregion, in south-central Brazil, is one of the largest foodplains in the world. Cycles of fooding and periodic fre have been determinant to the diversity of species in the ecoregion. In the fora of Pantanal, Leguminosae is one of the most rich families, and Mimosa is its most diversifed genus. Species of this genus are widely distributed and occur in the capões, sandy ridges and monominant stands (e.g. Cambarazal, Carandazal and Paratudal), in addition to native grasslands and pasture areas. In the Cerrado ecoregion, adaptations to fre have been recognized in some species of Mimosa. However, there is no data in the Pantanal ecoregion about which species of Mimosa are resilient to fre and/or fooding. This study aimed to investigate morphological adaptation in Mimosa in terms of resilience to fre and fooding. We verifed 45 specifc and infraspecifc taxa of Mimosa occurring in the Brazilian Pantanal, by means of the revision of literature, herbarium data, personal observations, plant collections and feld notesInstituto de Recursos BiológicosFil: Nogueira, Luan. Universidade Federal de Mato Grosso do Sul, BrasilFil: Morales, Matias. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Recursos Biológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Morón. Facultad de Agronomía y Ciencias Agroalimentarias; ArgentinaFil: Sartori, Angela Lucia. Universidade Federal de Mato Grosso do Sul, Brasi
Implantação de sistemas agroflorestais com açaizeiros para recuperação de áreas degradadas com a utilização das técnicas do sistema bragantino no Estado do Pará.
Áreas utilizadas com cultivos agrícolas ou pastagens, que se encontram com sinais de degradação, podem ser recuperadas com o cultivo de açaizeiros (Euterpe oleracea Mart.) em sistemas agroflorestais. Com o objetivo de elaborar, validar e recomendar sistemas diversificados de produção capazes de recuperar áreas degradadas e serem eficazes quanto à produtividade, custo de produção e sustentabilidade ambiental, conduziram-se estudos em uma área com indícios de degradação ambiental no município de Inhangapi, Pará. A implantação do sistema agroflorestal consistiu inicialmente do plantio de mudas de açaizeiros e de culturas anuais e perenes, cujo solo foi corrigido e adubado. As culturas anuais foram implantadas utilizando-se as técnicas do sistema bragantino, que consistiu no plantio consorciado de mandioca e feijão-caupi, cuja função é produzir alimentos, recuperar a fertilidade do solo e amortizar os custos iniciais das culturas perenes. O sistema contemplou, também, no segundo ano, o plantio de mudas de cacaueiros e de essências florestais. Ao final do processo de implantação das culturas perenes é possível se verificar a formação de um sistema agroflorestal, caracterizado por um açaizal enriquecido com espécies frutíferas e florestais, que fornecerá renda e produção diversificada, melhorando a cobertura vegetal da área e a proteção ao sol
Long-distance distribution of genuine energy-time entanglement
Any practical realization of entanglement-based quantum communication must be
intrinsically secure and able to span long distances avoiding the need of a
straight line between the communicating parties. The violation of Bell's
inequality offers a method for the certification of quantum links without
knowing the inner workings of the devices. Energy-time entanglement quantum
communication satisfies all these requirements. However, currently there is a
fundamental obstacle with the standard configuration adopted: an intrinsic
geometrical loophole that can be exploited to break the security of the
communication, in addition to other loopholes. Here we show the first
experimental Bell violation with energy-time entanglement distributed over 1 km
of optical fibers that is free of this geometrical loophole. This is achieved
by adopting a new experimental design, and by using an actively stabilized
fiber-based long interferometer. Our results represent an important step
towards long-distance secure quantum communication in optical fibers.Comment: 6 pages, 3 figures. Matches published versio
Selective extraction of fatty acids and unsaponifiable matter of Caryocar brasiliense Camb and Acrocomia aculeata pulp.
A aplicação de N-mineral na fase reprodutiva não resulta em aumento de produtividade de grãos de soja.
Indicadores microbiológicos e bioquímicos de qualidade em solo de baixa fertilidade natural com diferentes manejos de calagem e adubação fosfatada.
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