982 resultados para Hypergraph-structured process
Resumo:
The Agricultural Production Systems slMulator, APSIM, is a cropping system modelling environment that simulates the dynamics of soil-plant-management interactions within a single crop or a cropping system. Adaptation of previously developed crop models has resulted in multiple crop modules in APSIM, which have low scientific transparency and code efficiency. A generic crop model template (GCROP) has been developed to capture unifying physiological principles across crops (plant types) and to provide modular and efficient code for crop modelling. It comprises a standard crop interface to the APSIM engine, a generic crop model structure, a crop process library, and well-structured crop parameter files. The process library contains the major science underpinning the crop models and incorporates generic routines based on physiological principles for growth and development processes that are common across crops. It allows APSIM to simulate different crops using the same set of computer code. The generic model structure and parameter files provide an easy way to test, modify, exchange and compare modelling approaches at process level without necessitating changes in the code. The standard interface generalises the model inputs and outputs, and utilises a standard protocol to communicate with other APSIM modules through the APSIM engine. The crop template serves as a convenient means to test new insights and compare approaches to component modelling, while maintaining a focus on predictive capability. This paper describes and discusses the scientific basis, the design, implementation and future development of the crop template in APSIM. On this basis, we argue that the combination of good software engineering with sound crop science can enhance the rate of advance in crop modelling. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved.
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A technique based on laser light diffraction is shown to be successful in collecting on-line experimental data. Time series of floc size distributions (FSD) under different shear rates (G) and calcium additions were collected. The steady state mass mean diameter decreased with increasing shear rate G and increased when calcium additions exceeded 8 mg/l. A so-called population balance model (PBM) was used to describe the experimental data, This kind of model describes both aggregation and breakage through birth and death terms. A discretised PBM was used since analytical solutions of the integro-partial differential equations are non-existing. Despite the complexity of the model, only 2 parameters need to be estimated: the aggregation rate and the breakage rate. The model seems, however, to lack flexibility. Also, the description of the floc size distribution (FSD) in time is not accurate.
Resumo:
Complete biological nutrient removal (BNR) in a single tank, sequencing batch reactor (SBR) process, is demonstrated here at full-scale on a typical domestic wastewater. The unique feature of the UniFed process is the introduction of the influent into the settled sludge blanket during the settling and decant periods of the SBR operation. This achieves suitable conditions for denitrification and anaerobic phosphate release which is critical to successful biological phosphorus removal, It also achieves a selector effect, which helps in generating a compact, well settling biomass in the reactor. The results of this demonstration show that it is possible to achieve well over 90% removal of GOD, nitrogen and phosphorus in such a process. Effluent quality achieved over a six-month operating period directly after commissioning was: 29 mg/l GOD, 0.5 mg/l NH4-N, 1.5 mg/l NOx-N and 1.5 mg/l PO4-P (50%-iles of daily samples). During an 8-day, intensive sampling period, the effluent BOD5 was
Resumo:
Background/Aims: The role of cytokines in hepatic injury has been examined for many liver diseases however little is known of the cytokine involvement in haemochromatosis. The aim of the current study was to examine the hepatic gene expression of potential proinflammatory and profibrogenic cytokines in haemochromatosis. Methods: Interferon-gamma, interleukin-10, transforming growth factor-beta(1) and tumor necrosis factor-alpha mRNA expression was assessed in liver tissue from 20 haemochromatosis patients, eight controls and eight chronic hepatitis C patients. To assess the immunophenotype of the inflammatory infiltrate in haemochromatosis, liver sections were subjected to immunohistochemistry using markers for macrophages (CD68, HAM56, MAC387) or T cells (CD3 and CD45RO). Results: Interferon-gamma mRNA was increased in both haemochromatosis (0.29+/-0.08%, P=0.01) and hepatitis C patients (1.02+/-0.32%, P=0.03) compared to controls (0.04+/-0.01%). Interleukin-10 mRNA was significantly decreased in both haemochromatosis and hepatitis C patients (0.01+/-0.003%, P=0.008 and 0.03+/-0.015%, P=0.02, respectively) compared to controls (0.12+/-0.01%). CD3 positive T-cell number was significantly correlated with increasing hepatic iron concentration (r=0.56, P=0.03). Conclusions: This study has demonstrated a distinct pattern of cytokine gene expression in haemochromatosis, which resembles that of inflammatory conditions such as chronic hepatitis C. These factors may play a role in the development of iron-induced hepatic fibrosis in haemochromatosis. (C) 2003 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.
Nitrification of high strength ammonia wastewtaer treatment - process selection is the major factor.
Resumo:
Biological nitrogen removal via the nitrite pathway in wastewater treatment is very important in Saving the cost of aeration and as an electron donor for denitrification. Wastewater nitrification and nitrite accumulation were carried out in a biofilm airlift reactor with autotrophic nitrifying biofilm. The biofilm reactor showed almost complete nitrification and most of the oxidized ammonium was present as nitrite at the ammonium load of 1.5 to 3.5 kg N/m3.d. Nitrite accumulation was stably achieved by the selective inhibition of nitrite oxidizers with free ammonia and dissolved oxygen limitation. Stable 100% conversion to nitrite could also be achieved even under the absence of free ammonia inhibition on nitrite oxidizers. Batch ammonium oxidation and nitrite oxidation with nitrite accumulating nitrifying biofilm showed that nitrite Oxidation was completely inhibited when free ammonia is higher than 0.2 mg N/L. However, nitrite oxidation activity was recovered as soon as the free ammonia concentration was below the threshold level when dissolved oxygen concentration was not the limiting factor. Fluorescence in situ hybridization analysis of cryosectioned nitrite accumulating nitrifying biofilm showed that the β-subclass of Proteobacteria, where ammonia oxidizers belong, was distributed outside the biofilm whereas the α-subclass of Proteobacteria, where nitrite oxidizers belong, was found mainly in the inner part of the biofilm. It is likely that dissolved oxygen deficiency or limitation in the inner part of the nitrifying biofilm, where nitrite oxidizers exist, is responsible for the complete shut down of the nitrite oxidizers activity under the absence of free ammonia inhibition.
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This paper describes a process-based metapopulation dynamics and phenology model of prickly acacia, Acacia nilotica, an invasive alien species in Australia. The model, SPAnDX, describes the interactions between riparian and upland sub-populations of A. nilotica within livestock paddocks, including the effects of extrinsic factors such as temperature, soil moisture availability and atmospheric concentrations of carbon dioxide. The model includes the effects of management events such as changing the livestock species or stocking rate, applying fire, and herbicide application. The predicted population behaviour of A. nilotica was sensitive to climate. Using 35 years daily weather datasets for five representative sites spanning the range of conditions that A. nilotica is found in Australia, the model predicted biomass levels that closely accord with expected values at each site. SPAnDX can be used as a decision-support tool in integrated weed management, and to explore the sensitivity of cultural management practices to climate change throughout the range of A. nilotica. The cohort-based DYMEX modelling package used to build and run SPAnDX provided several advantages over more traditional population modelling approaches (e.g. an appropriate specific formalism (discrete time, cohort-based, process-oriented), user-friendly graphical environment, extensible library of reusable components, and useful and flexible input/output support framework). (C) 2003 Published by Elsevier Science B.V.
Resumo:
O presente artigo tem por objetivo demonstrar como um processo de implementa????o se modifica e ?? adaptado ao longo do tempo, podendo conduzir a um redesenho da pol??tica p??blica. Utiliza-se como estudo de caso o programa Cultura Viva. A pesquisa em que se baseia o artigo foi realizada por meio de entrevistas semiestruturadas com gestores do programa Cultura Viva e gestores de pontos de cultura, bem como por meio de um survey com os pontos de cultura do Estado de S??o Paulo e seus Munic??pios. Os resultados revelam que a implementa????o do programa alterou os crit??rios estabelecidos no processo de formula????o e incluiu novos instrumentos de gest??o, redesenhando assim a pol??tica p??blica
Resumo:
O objetivo deste artigo ?? apresentar tr??s a????es empreendedoras em organiza????es p??blicas premiadas pela ENAP no concurso Inova????o na Gest??o P??blica Federal. A partir da revis??o de literatura e estudo de caso, ser??o confrontados os diversos tipos e modelos de processos de inova????o, para identificar as dificuldades apontadas e as solu????es adotadas nas a????es premiadas. Foram selecionados tr??s casos de iniciativas inovadoras no INSS, apontando a origem, caracter??sticas, amplitude e o modelo do processo. Nosso quadro te??rico de refer??ncia est?? estruturado no sentido de aprofundar a percep????o, bem como nos dar condi????es de comparar alguns estudos e apontar lacunas, se existentes. A pesquisa foi realizada por meio de metodologia qualitativa, explorat??ria e adotando a estrat??gia de investiga????o do estudo de caso. A revis??o de literatura teve como objetivo identificar o que se encontra dispon??vel em livros, artigos, teses e, inclusive, experi??ncias. A conclus??o alcan??ada no artigo ?? a de que, apesar dos alegados entraves e limita????es, o intraempreendedorismo se faz presente nas organiza????es p??blicas e vem crescentemente sendo adotado pelas chefias ou mesmo por funcion??rios sem nenhum tipo de fun????o comissionada, como relatado em um dos casos. A inova????o nas organiza????es p??blicas, representada pelo intraempreendedorismo das experi??ncias premiadas pelo concurso, confirma nosso quadro te??rico na medida em que a????es empreendedoras geradoras de inova????o se fazem presentes nas organiza????es p??blicas, em todos os seus processos e meios.
Resumo:
Este estudo teve como objetivo analisar como ocorre a inclusão de dois bebês surdos (de 1 ano) na educação infantil de um Centro Municipal de Educação Infantil (CMEI) do município de Vitória/ES. Como aporte teórico foi utilizada a perspectiva Histórico-Cultural do desenvolvimento humano, sob a perspectiva que o sujeito se constitui nas relações sociais, como um ser ativo que transforma e é transformado nessas relações. Nesse contexto, o desenvolvimento implica a relação com o outro e a mediação da linguagem, meio de comunicação e de constituição do pensamento. Assim, no caso dos bebês surdos, destaca-se a LIBRAS como língua privilegiada que deve ser apropriada por eles e ensinada no cotidiano da educação infantil. Como opção metodológica, desenvolvemos um estudo de caso de inspiração etnográfica, por entendermos que essa metodologia permite atender apropriadamente ao objetivo do estudo. Para a coleta de dados, adotamos recursos como observação participante, registro em diário de campo, entrevistas semiestruturadas com os sujeitos participantes da pesquisa e análise documental. Na análise dos dados, tomamos como eixos de análise: as concepções dos profissionais a respeito da inclusão, surdez e do trabalho com os bebês surdos; o cuidado e a educação dos bebês surdos e as atividades lúdicas na sala dos bebês. As análises indicam que muitos profissionais têm dúvidas a respeito da inclusão e que a falta do conhecimento da LIBRAS por parte de muitos profissionais, leva à utilização de outros recursos de comunicação, como os gestos. A vivência e interação em LIBRAS entre as crianças e a maior parte dos profissionais da escola com os bebês surdos torna-se um desafio, sobressaindo a necessidade de mais profissionais com o conhecimento da LIBRAS para atender às crianças surdas em diferentes espaços no cotidiano da educação infantil, na perspectiva de potencializar o seu desenvolvimento e a constituição de sua identidade. Todavia, os profissionais da escola são movidos pela preocupação com a inclusão e o aprendizado da LIBRAS, esforçando-se no sentido de buscar novas formas de trabalho para/com as crianças surdas. Além disso, o empenho da equipe bilíngue na estruturação do cotidiano da educação infantil merece destaque, não só pelo trabalho que faz enquanto equipe bilíngue, mas pelo incentivo e auxílio aos outros profissionais.