High Order Numerical Methods
Mostrando 37-47 de 47 artigos, teses e dissertações.
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37. Visual performance in myopic correction with spectacles and soft contact lenses / "Desempenho visual na correção de miopia com óculos e lentes de contato gelatinosas"
Objective: to evaluate the visual performance(VP) by Visual acuity(VA)Logmar of high contrast, sensibility of contrast(SC) and wavefront (WF) in myopic patients correct with spectacles and 3 SCL Methods: prospective clinical trial was performed in 40 myopic patients(-1,00 D and -4,50 D). Exams: VA, WF and CS. Results: The WF analysis detected a significant d
Publicado em: 2004
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38. Integração das equações diferenciais do filtro digital de Butterworth mediante algoritmo de quadratura numérica de ordem elevada / Integration of the Butterworth digital filters differential equations using numerical algorithm of high order integrator
In this work is presented the development of hermitian algorithm for integration of the Butterworth digital filters differential equations by means of high order numerical one step operators. The Butterworth filters theory is presented based on the Fourier transform. Numerical examples show that the results of the developed hermitian algorithm are more a
Publicado em: 2003
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39. Impacto de um esquema objetivo de análise nas simulações de eventos meteorológicos num modelo regional. / Impact of an analysis objective scheme to simulate meteorological events regional model.
An objective scheme of data analysis was implemented in a limited area model for numerical forecast. It is composed of two parts: initialization and continuous data assimilation. The hydrostatic numerical model used was developed by the Japan Meteorology Agency. It is written in flux form using s-p vertical coordinates. The initialization procedure combines
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 01/04/2002
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40. Impacto de um esquema objetivo de análise nas simulações de eventos meteorológicos num modelo regional. / Impact of an analysis objective scheme to simulate meteorological events regional model.
An objective scheme of data analysis was implemented in a limited area model for numerical forecast. It is composed of two parts: initialization and continuous data assimilation. The hydrostatic numerical model used was developed by the Japan Meteorology Agency. It is written in flux form using s-p vertical coordinates. The initialization procedure combines
Publicado em: 2002
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41. Análise e implementação de esquemas de convecção e modelos de turbulência para simulação de escoamentos incompressíveis envolvendo superfícies livres. / Analysis and implementation of convection schemes and turbulence models for simulation of incompressible flows involving free surfaces.
A considerable part of fluid flows encountered in technological applications is characterised by involving high-Reynolds numbers, especially those in turbulent regime and with free-surface. It is extremely difficult to obtain representative numerical solutions for this class of problems, due to the non-linear nature of the partial differential equations invo
Publicado em: 2001
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42. Numerical simulation of a two-stage turbine for turbopumps of liquid propellant rocket engine.
The main aim is to understand the gas dynamic process, which occurs inside a two-stage turbine and to propose an algorithm for the simulation of a two-stage turbine at design and off-design points. The explanation of each chapter is constructed to make further works easy, which should be the main of any research work that needs to be continued. Moreover, the
Publicado em: 1999
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43. ANÁLISE DO COMPORTAMENTO DE UM MURO DE CONTENÇÃO UTILIZANDO PNEUS / BEHAVIOUR OF A GRAVITY RETAINING WALL USING SCRAP TIRES / ANÁLISIS DEL COMPORTAMIENTO DE UN MURO DE CONTENCIÓN UTILIZANDO NEUMÁTICOS
Construction of a retaining wall using scrap tires and soil is presented in this thesis. The technique was developed as part of a research program at PUC-Rio in collaboration with University of Ottawa and Geo-Rio. The present work consisted of building and analyzing an experimental retaining wall which was constructed in Jacarepaguá, Rio de Janeiro and made
Publicado em: 1998
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44. Otimização do itinerario de sondas de intervenção / Workover rig itinerary otimization
The costs of workover and the loss of revenue in wells waiting workover rigs are very high. This work proposes methods to prioritize these wells in order to minimize the total cost. To determine the workover sequence it is necessary to compare the rig expense with the wells losses. To calculate the wells losses, it is necessary to analyze the monetary influe
Publicado em: 1997
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45. Modelagem e simulação do processo de oxidação do etanol a acetaldeido
A new high performance catalyst is proposed to oxidize ethanol to acetaldehyde. The available experimental data are analysed using two different reactional mechanisms. After choosing a Temkin type mechanism, the single reaction rate equation to be used in the simulations is determined. Then,a continuous bidimendional steady-state model for the catalytic bed
Publicado em: 1992
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46. Esquemas de alta resolução para controle da dispersão numerica em simulação de reservatorios
Standard finite-diference reservoir simulation normally uses single-point upstream welghting to approximate the components of the convective flow term at the interfaces between blocks. This procedure stabilizes the numerical solution, but introduces high levels of numerical dispersion, difficulting the correct interpretation of the simulated results. Exponen
Publicado em: 1991
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47. Transferencia de calor mistura-parede em leitos fluidizados recirculantes
This work involved the analysis of the influence of volumetric concentration, nature and size of solid particles on determining the convective heat transfer coeficient between solid-gas: mixtures and heated walls influidized beds with high air velocities and solids recirculation. The experimental results led to a correlation for predicting Nusselt Number as
Publicado em: 1986