864 resultados para Conceptual change model


Relevância:

80.00% 80.00%

Publicador:

Resumo:

The IPD Annual Index is the largest and most comprehensive Real Estate market index available in the UK Such coverage however inevitably leads to delays in publication. In contrast there are a number of quarterly and monthly indices which are published within days of the year end but which lack the coverage in terms of size and numbers of properties. This paper analyses these smaller but more timely indices to see whether such indices can be used to predict the performance of the IPD Annual Index. Using a number of measures of forecasting accuracy it is shown that the smaller indices provide unbiased and efficient predictions of the IPD Annual Index. Such indices also significantly outperform a naive no-change model. Although no one index performs significantly better than the others. The more timely indices however do not perfectly track the IPD Annual Index. As a result any short run predictions of performance will be subject to a degree of error. Nevertheless the more timely indices, although lacking authoritative coverage, provide a valuable service to investors giving good estimates of Real Estates performance well before the publication of the IPD Annual Index.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The Canadian Middle Atmosphere Model is used to examine the sensitivity of simulated climate to conservation of momentum in gravity wave drag parameterization. Momentum conservation requires that the parameterized gravity wave momentum flux at the top of the model be zero and corresponds to the physical boundary condition of no momentum flux at the top of the atmosphere. Allowing momentum flux to escape the model domain violates momentum conservation. Here the impact of momentum conservation in two sets of model simulations is investigated. In the first set, the simulation of present-day climate for two model-lid height configurations, 0.001 and 10 hPa, which are identical below 10 hPa, is considered. The impact of momentum conservation on the climate with the model lid at 0.001 hPa is minimal, which is expected because of the small amount of gravity wave momentum flux reaching 0.001 hPa. When the lid is lowered to 10 hPa and momentum is conserved, there is only a modest impact on the climate in the Northern Hemisphere; however, the Southern Hemisphere climate is more adversely affected by the deflection of resolved waves near the model lid. When momentum is not conserved in the 10-hPa model the climate is further degraded in both hemispheres, particularly in winter at high latitudes, and the impact of momentum conservation extends all the way to the surface. In the second set of simulations, the impact of momentum conservation and model-lid height on the modeled response to ozone depletion in the Southern Hemisphere is considered, and it is found that the response can display significant sensitivity to both factors. In particular, both the lower-stratospheric polar temperature and surface responses are significantly altered when the lid is lowered, with the effect being most severe when momentum is not conserved. The implications with regard to the current round of Intergovernmental Panel on Climate Change model projections are discussed.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper analyzes the most significant events occurring in Brazil`s educational, social and political areas over the last half century, viewed against a background of relevant worldwide events. The hypothesis presented here is that the relations between the country`s educational policies, the demands of the various segments of academia, and the public school system have always been strained. This strain has contributed positively to the evolution of academic knowledge and production, to the design of more modern curricular projects by institutional authorities, and to the initial recognition of the specific construction of school knowledge by the school system itself. However, the interaction of these major institutions lacks a crucial element-one that would lead to an effective change in the education of science teachers and produce a positive impact on Brazil`s schools-namely, the wholehearted participation of science teachers themselves. With this analysis, we intend to contribute by offering some perspectives and proposals for science teacher education in Brazil.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper presents the results of a new investigation of the Guarani Aquifer System (SAG) in Sao Paulo state. New data were acquired about sedimentary framework, flow pattern, and hydrogeochemistry. The flow direction in the north of the state is towards the southwest and not towards the west as expected previously. This is linked to the absence of SAG outcrop in the northeast of Sao Paulo state. Both the underlying Piramboia Formation and the overlying Botucatu Formation possess high porosity (18.9% and 19.5%, respectively), which was not modified significantly by diagenetic changes. Investigation of sediments confirmed a zone of chalcedony cement close to the SAG outcrop and a zone of calcite cement in the deep confined zone. The main events in the SAG post-sedimentary history were: (1) adhesion of ferrugineous coatings on grains, (2) infiltration of clays in eodiagenetic stage, (3) regeneration of coatings with formation of smectites, (4) authigenic overgrowth of quartz and K-feldspar in advanced eodiagenetic stage, (5) bitumen cementation of Piramboia Formation in mesodiagenetic stage, (6) cementation by calcite in mesodiagenetic and telodiagenetic stages in Piramboia Formation, (7) formation of secondary porosity by dissolution of unstable minerals after appearance of hydraulic gradient and penetration of the meteoric water caused by the uplift of the Serra do Mar coastal range in the Late Cretaceous, (8) authigenesis of kaolinite and amorphous silica in unconfined zone of the SAG and cation exchange coupled with the dissolution of calcite at the transition between unconfined and confined zone, and (9) authigenesis of analcime in the confined SAG zone. The last two processes are still under operation. The deep zone of the SAG comprises an alkaline pH, Na-HCO(3) groundwater type with old water and enriched delta(13)C values (<-3.9), which evolved from a neutral pH, Ca-HCO(3) groundwater type with young water and depleted delta(13)C values (>-18.8) close to the SAG outcrop. This is consistent with a conceptual geochemical model of the SAG, suggesting dissolution of calcite driven by cation exchange, which occurs at a relatively narrow front recently moving downgradient at much slower rate compared to groundwater flow. More depleted values of delta(18)O in the deep confined zone close to the Parana River compared to values of relative recent recharged water indicate recharge occur during a period of cold climate. The SAG is a ""storage-dominated"" type of aquifer which has to be managed properly to avoid its overexploitation. (C) 2011 Elsevier Ltd. All rights reserved.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This study presents an approach to combine uncertainties of the hydrological model outputs predicted from a number of machine learning models. The machine learning based uncertainty prediction approach is very useful for estimation of hydrological models' uncertainty in particular hydro-metrological situation in real-time application [1]. In this approach the hydrological model realizations from Monte Carlo simulations are used to build different machine learning uncertainty models to predict uncertainty (quantiles of pdf) of the a deterministic output from hydrological model . Uncertainty models are trained using antecedent precipitation and streamflows as inputs. The trained models are then employed to predict the model output uncertainty which is specific for the new input data. We used three machine learning models namely artificial neural networks, model tree, locally weighted regression to predict output uncertainties. These three models produce similar verification results, which can be improved by merging their outputs dynamically. We propose an approach to form a committee of the three models to combine their outputs. The approach is applied to estimate uncertainty of streamflows simulation from a conceptual hydrological model in the Brue catchment in UK and the Bagmati catchment in Nepal. The verification results show that merged output is better than an individual model output. [1] D. L. Shrestha, N. Kayastha, and D. P. Solomatine, and R. Price. Encapsulation of parameteric uncertainty statistics by various predictive machine learning models: MLUE method, Journal of Hydroinformatic, in press, 2013.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A presente dissertação tem por objetivo identificar - por meio do estudo de caso da implantação do PRC - Programa de Racionalização e Competitividade na Caixa Econômica Federal - se existem padrões de respostas e soluções organizacionais que possam ensejar um modelo básico de inovação e mudança organizacional tipicamente brasileiro. Considerando que o turbulento ambiente empresarial brasileiro desenvolveu empresas altamente adaptáveis às provocações ambientais por meio de diversos modelos de gestão de mudança organizacional, o presente estudo num primeiro momento faz uma revisão da literatura sobre o tema. Em seguida, descreve o contexto e os diversos modelos de gestão experimentados pela CAIXA, no período de 1989 a 1998, visando registrar e sistematizar informações que poderão permitir que se vislumbre, ao longo do tempo, traços comuns que possam caracterizar esse típico modelo de inovação e mudança organizacional brasileiro. Os resultados obtidos da pesquisa de campo, respaldados pelo exame bibliográfico, permitiu concluir que o processo de mudança experimentado pela organização em virtude da implementação do programa foi despertado tanto por variáveis do contexto interno quanto do contexto externo, com semelhante intensidade. Adicionalmente, pode-se concluir que houve mais facilidade da organização em lidar com as perspectivas estratégica, estrutural e humana, e mais dificuldade em lidar com as perspectivas tecnológica, cultural e política. Confirma-se, portanto, que algumas perspectivas do processo de mudança experimentado pela CAIXA denotaram práticas de inovação organizacional e que, entretanto, outras perspectivas não puderam ser reproduzidas de modo confiável, em uma escala significativa a custos razoáveis.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este pesquisa, inserida no campo de estudo sobre mudanças organizacionais, buscou investigar como é realizada a gestão de mudanças na Criminalística da Polícia Federal. Para isso, partiu-se de um referencial teórico para a estruturação de categorias de análise essenciais para o estudo do tema, agrupadas em três dimensões: conteúdo da mudança, processo de implementação da mudança e contexto em que ocorreu a mudança. Dessa forma, essa pesquisa de caráter qualitativo avaliou o processo de gestão de mudança ocorrido por meio da implementação de indicadores de complexidade na Criminalística da Polícia Federal, à luz do modelo proposto por John P. Kotter para a implementação eficaz de mudanças nas organizações, considerando sua interação com as circunstâncias contextais prevalecentes. Para a coleta de dados foram utilizadas entrevistas semiestruturadas com os componentes do corpo gerencial e diretor da Criminalística, responsáveis pela condução do processo de implementação da mudança. A análise de documentos institucionais e a observação direta complementaram a coleta dos dados. Os resultados apontaram para uma significante concorrência dos fatores relacionados às três dimensões estudadas que impediu o alcance dos objetivos esperados com a mudança, destacando-se: a) aspecto negativo relacionado à própria natureza da mudança, que se enquadra no campo de avaliação de desempenho, questão polêmica que levanta muitas discussões; b) contexto organizacional desfavorável, por estar inserida em uma organização policial, com forte cultura disciplinar e punitiva; c) processo de gestão de mudança mal conduzido, de acordo com modelo teórico para a implementação eficaz de mudanças nas organizações proposto por Kotter (1995, 1997).

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Procurou-se identificar as consequências mais importantes da concepção de ciência de Popper, que deu origem a um rico debate na Filosofia das Ciências, para o Ensino de Ciências. O acompanhamento deste debate permite perceber a riqueza do processo científico, reconhecendo as contribuições daqueles que debateram com Popper; bem como a importância dos aspectos da ciência que Popper valorizou e procurou preservar. As críticas e os debates em torno das abordagens de mudança conceitual contribuíram para a percepção da riqueza e complexidade desse processo. Quando considerados os objetivos institucionais das escolas e as expectativas sociais em torno da compreensão adequada e da procura de superação dos paradigmas vigentes a manutenção de certos aspectos, inerentes ao processo de mudança conceitual, pode se mostrar relevante. Neste sentido, a obra de Popper pode oferecer importante apoio para valorizar aspectos racionais que poderiam presidir o processo de aprender Ciências.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A suit able decision-making on managing a contaminated site characterization program is strongly dependent of the diagnosis process. A detailed diagnosis can be done based on a Conceptual Site Model (CSM) elaboration using high resolution site characterization tools. The piezocone (CPTu) test is a high resolution tool which allows attaching several specific sensors, like the resistivity probe. This hybrid device is called the resistivity piezocone (RCPTu). A simulated geo-environmental site characterization program was performed on an erosion site using different tools (direct push tools soil samplers, hollow stem auger (HSA) drilling and RCPTu tests) to develop the CSM for a site similar to the Brazilian conditions. It was observed a good agreement between the site profiles interpreted by the different methods. The resistivity sensor attached to the piezocone improved the interpretation and the decision-making process on site was significantly better for the CSM elaboration. The RCPTu test data also allowed identifying the hydrogeological heterogeneities. The present study shows that the RCPTu test is also a useful and powerful tool to development an accurate CSM in a Brazilian condition, especially in an approach that prioritizes high resolution geo-environmental investigation. © 2013 Taylor & Francis Group.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Pós-graduação em Educação para a Ciência - FC