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CAD and CAE Integration Through Scientific Visualization Techniques for Illumination Design

Tsinghua Science and Technology 2008年第S1期13卷 26-33页

作者： Tiago Martinuzzi Buriol Sergio Scheer Graduate Program in Numerical Methods for Engineering Civil Engineering Research Center Federal University of Parana

Engineers tend to use different software to perform tasks such as geometry modeling, database management, numerical analysis, and visualization. This may cause decrease of productivity and loss of information during the conversion process between different data file formats. This paper presents a computer aided design (CAD) and computer aided engineering (CAE) system integration using scientific visualization tools and techniques. It deals with the development of a 3D CAD add-in for lighting analysis which uses the CAD model as 3D interface for creating a lighting scheme, processing, and visualizing 2D or 3D illuminance fields. Visualization features as color and contour mapping were developed using the visualization toolkit (VTK) toolkit. The application integrates all functionalities of the 3D CAD with tools for light sources database management, pre-processing, processing, and post-processing of illuminance fields in a single environment. This approach increases productivity and eliminates the need for different software.

关键词： illumination design scalar fields post-processing 3D computer aided design (CAD) visualization toolkit (VTK) systems integration

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High Order of Accuracy for Poisson Equation Obtained by Grouping of Repeated Richardson Extrapolation with Fourth Order Schemes

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Computer Modeling in engineering & Sciences 2021年第8期128卷 699-715页

作者： Luciano Pereira da Silva Bruno Benato Rutyna Aline Roberta Santos Righi Marcio Augusto Villela Pinto Graduate Program in Numerical Methods in Engineering Federal University of ParanaCuritiba81531-980Brazil Graduate Program in Space Sciences and Technologies Aeronautics Institute of TechnologySao Jose dos Campos12228-900Brazil Department of Mechanical Engineering Federal University of ParanaCuritiba81531-980Brazil

In this article,we improve the order of precision of the two-dimensional Poisson equation by combining extrapolation techniques with high order *** high order solutions obtained traditionally generate non-sparse matrices and the calculation time is very *** can obtain sparse matrices by applying compact *** this article,we compare compact and exponential finite difference schemes of fourth *** numerical solutions are calculated in quadruple precision(Real*16 or extended precision)in FORTRAN language,and iteratively obtained until reaching the round-off error magnitude around 1.0E−*** procedure is performed to ensure that there is no iteration *** Repeated Richardson Extrapolation(RRE)method combines numerical solutions in different grids,determining higher orders of *** main contribution of this work is based on a process that initializes with fourth order solutions combining with RRE in order to find solutions of sixth,eighth,and tenth order of *** multigrid Full Approximation Scheme(FAS)is also applied to accelerate the convergence and obtain the numerical solutions on the fine grids.

关键词： Tenth order accuracy RRE compact scheme exponential scheme multigrid finite difference

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On the Robustness of the xy-Zebra-Gauss-Seidel Smoother on an Anisotropic Diffusion Problem

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Computer Modeling in engineering & Sciences 2018年第11期117卷 251-270页

作者： Michely Laís de Oliveira Marcio Augusto Villela Pinto Simone de Fátima Tomazzoni Goncalves Grazielli Vassoler Rutz Graduate Program in Numerical Methods in Engineering Federal University of Paraná81531-980Curitiba-PRBrazil Department of Mechanical Engineering Federal University of Paraná81531-980Curitiba-PRBrazil Federal Institute of Education Science and Technology of Santa Catarina89813-000Chapecó-SCBrazil.

Studies of problems involving physical anisotropy are applied in sciences and engineering,for instance,when the thermal conductivity depends on the *** this study,the multigrid method was used in order to accelerate the convergence of the iterative methods used to solve this type of *** asymptotic convergence factor of the multigrid was determined empirically(computer aided)and also by employing local Fourier analysis(LFA).The mathematical model studied was the 2D anisotropic diffusion equation,in whichε>0 was the coefficient of a *** equation was discretized by the Finite Difference Method(FDM)and Central Differencing Scheme(CDS).Correction Scheme(CS),pointwise Gauss-Seidel smoothers(Lexicographic and Red-Black ordering),and line Gauss-Seidel smoothers(Lexicographic and Zebra ordering)in x and y directions were used for building the *** best asymptotic convergence factor was obtained by the Gauss-Seidel method in the direction x for 0<ε<<1 and in the direction y forε>>*** this sense,an xy-zebra-GS smoother was proposed,which proved to be efficient and robust for the different anisotropy ***,the convergence factors calculated empirically and by LFA are in agreement.

关键词： Physical anisotropy diffusion problem finite difference method multigrid,local Fourier analysis Gauss-Seidel zebra

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Performance of the multigrid method with time-stepping to solve 1D and 2D wave equations

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International Journal for Computational methods in engineering Science and Mechanics 2022年第1期23卷 45-56页

作者： Malacarne, Maicon F. Pinto, Marcio A. V. Franco, Sebastião R. Graduate Program on Numerical Methods in Engineering–PPGMNE Federal University of Parana–UFPR PR Curitiba Brazil Department of Mechanical Engineering Federal University of Parana–UFPR PR Curitiba Brazil Department of Mathematics State University of Centro-Oeste–UNICENTRO PR Irati Brazil

This work aims to discuss a proposed solution for wave equations that utilize discretization by means of the finite difference method, weighted by a parameter η, with sweeping done according to the time-stepping method. The multigrid method is employed to speed up the convergence in obtaining the solution of the system of equations resulting from the discretization. To validate the proposed model, the discretization errors, effective and apparent orders, convergence factor, orders of complexity, and the computational time were assessed. A comparison between the singlegrid and multigrid methods was carried out in order to determine the most advantageous one. © 2021 Taylor & Francis Group, LLC.

关键词： Wave equations

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Analysis of A 2D cathodic protection system for a buried slender structure with the dual boundary element method

Analysis of A 2D cathodic protection system for a buried sle...

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European Congress on Computational methods in Applied Sciences and engineering, ECCOMAS 2004

作者： De Lacerda, Luiz A. De Oliveira, Paulo A. Lázaris, José Da Silva, José M. LACTEC - Institute of Technology for Development Materials Department Centro Politécnico Cx. P. 19067 Curitiba Brazil PPGMNE - Post-Graduate Program on Numerical Methods in Engineering UFPR - Federal University of Paraná Curitiba Brazil

In this paper a boundary element formulation is developed and used for the analysis of cathodic protection systems of buried slender structures, such as foundations of electric transmission line towers. The foundation is basically a truss structure and the slenderness of the pieces composing it, brings numerical difficulties into the classical boundary element method. To avoid this problem, the dual boundary element method is implemented: combination of standard and hypersingular integral equations to form a mathematically well-posed system. A simple experiment is carried out where a galvanized metallic sheet is buried alongside two Copper electrodes (anodes) in parallel, with the objective of simulating a two-dimensional problem. The soil resistivity properties are measured along the depth and the non-linear polarization curves describing the relation between the current density and the electrochemical potential at the metallic sheet is investigated. Two situations are analysed: a) current is injected into the ground through both electrodes;b) current is injected through only one of the electrodes. In the numerical implementation, the soil is modeled as a homogeneous layered half-space with a different property for each layer. The validity of the proposed dual approach is discussed and compared with the measurements of potential at the ground surface.

关键词： Boundary element method

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Damage effects from dynamic interaction between vehicles, irregularities and railway bridges in the nonlinear dynamic response of structures

Damage effects from dynamic interaction between vehicles, ir...

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作者： De Abeche, T.O. Machado, R. Dalledone Abdalla Filho, J.E. Beghetto, L.F.M. De Souza, L.A.F. Mechanical Engineering Graduate Program Pontifical Catholic University of Paraná Curitiba Brazil Numerical Methods in Engineering Graduate Program Federal University of Paraná Curitiba Brazil Department of Civil Environmental and Architectural Engineering University of Colorado Boulder United States Civil Engineering Graduate Program Federal Technological University of Paraná Curitiba Brazil Academic Department of Civil Construction Federal Technological University of Paraná Curitiba Brazil Department of Civil Engineering Federal Technological University of Paraná Apucarana Brazil

The effects of vehicle-structure interaction have a significant effect on the dynamic responses of both the vehicle and the structure with several applications within the railways field. When the vehicle loads are capable of producing accumulated strains sufficient to cause damage to the structure, the dynamic responses change completely. By crossing a railway bridge, the vehicle is subjected to the effects of track irregularities. The vehicle's movement on the bridge is already a dynamic action on the structure. However, the irregularities of the track tend to excite the vehicle dynamically which in turns triggers additional vibrations in the structure apart from those produced by its own movement, increasing the structural degree of damage. This modifies the structural dynamic responses, increasing the magnitude and the oscillations within the same time interval especially at critical speeds of the vehicle, capable of provoking some resonance. Apart from changing the displacements, velocities and accelerations, the damage alters the structural natural frequencies of vibration. It is not possible to analyse such effects with linear dynamic models. This paper evaluates, using the finite element method, the nonlinear dynamic effects in a reinforced concrete bridge where the degree of damage is altered over time using a damage mechanics procedure. © Civil-Comp Press, 2016.

关键词： Dynamic response

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A PARAMETRIC MODEL DISCUSSION FOR THE CONCRETE EXPANSION DUE TO AAR

A PARAMETRIC MODEL DISCUSSION FOR THE CONCRETE EXPANSION DUE...

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第十二届国际混凝土碱集料反应会议

作者： Rogério Carrazedo Luiz Alkimin de Lacerda Department of Civil Engineering Graduate Program in Numerical Methods in Engineering Federal University of Parana Curitiba Brazil.LACTEC-Institute of Technology for Development Curitiba Brazil Department of Civil Engineering Graduate Program in Numerical Methods in Engineering Federal University of Paraná Curitiba Brazil. LACTEC-Institute of Technology for Development Curitiba Brazil

Concrete strength and durability reduction are two of the major consequences of the long-term chemical reaction evolution between the cement alkali and certain minerals from the aggregate. This reaction is known as alkali-aggregate reaction. It provokes a heterogeneous expansion of the concrete causing geometry changes and eventually, loss of functionality. In concrete dams these effects can be very costly and the development of numerical tools to diagnose and correct the problem should be welcome. In this work, a parametric model to simulate concrete expansion is proposed, which uses the main AAR influence factors to form its basis. The employed methodology consists on obtaining the spatial distribution of these influence factors, parameters normalization and the use of a constitutive relationship to retrieve the expansive AAR rate of deformation. An optimization technique is also employed to adjust the computed parameters to existing field measurements. The methodology was developed in a commercial finite element package and tested in a for simple three-dimensional finite element model.

关键词： Alkali-aggregate reaction, finite element method, parametric model, influence factors.

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Classification of power quality considering voltage sags occurred in feeders

Classification of power quality considering voltage sags occ...

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5th International Joint Conference on Computational Intelligence, IJCCI 2013

作者： Góes, Anderson Roges Teixeira Steiner, Maria Teresinha Arns Neto, Pedro José Steiner Graduate Programs in Numerical Methods in Engineering Federal University of Paraná Centro Politécnico CP: 19081 CEP: 81531-990 Curitiba PR Brazil Graduate Program in Industrial and Systems Engineering Pontifical Catholic University of Paraná Rua Imaculada Conceição 1155 Prado Velho CEP: 80.215-901 Curitiba PR Brazil Numerical Methods in Engineering and Industrial Engineering Federal University of Paraná Centro Politécnico CP: 1908 CEP: 81531-990 Curitiba PR Brazil Graduate Programs in Business Administration Federal University of Paraná Av. Pref. Lothario Meissner 632 CEP: 80210-170 Curitiba PR Brazil

ISBN: (纸本)9789898565778

In this paper we propose a methodology to classify Power Quality for feeders, based on sags and by the use of KDD technique, establishing a quality level printed in labels. To support the methodology, it was applied to feeders on a substation located in Curitiba, Paraná, Brazil, based on attributes such as sag length, duration and frequency (number of occurrences on a given period of time). In the search for feeders quality classification, on the Data Mining stage, the main stage on KDD process, three different techniques were used in a comparatively way for pattern recognition: Artificial Neural Networks, Support Vector Machines an Genetic Algorithms. Those techniques presented acceptable results in classification feeders with no possible classification using a simplified method based on maximum number of sags. Thus, by printing the label with information and Quality level, utilities companies can get better organized for mitigation procedures, by establishing clear targets.

关键词： Pattern recognition

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Construction of school timetable with emphasis in minimization of twinned lessons and windows 1

Construction of school timetable with emphasis in minimizati...

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1st Pan-American Congress on Computational Mechanics, PANACM 2015 and the 11th Argentine Congress on Computational Mechanics, MECOM 2015

作者： Mikuska, Márcia Inês Schabarum Rosa, Carlos Eurico Galvão Góes, Anderson Roges Teixeira Scheer, Sérgio Federal University of Paraná Graduate Program on Numerical Methods in Engineering P.O Box 19011 Curitiba-PR81531-980 Brazil Federal University of Paraná Advanced Campus Jandaia Do sul 426 Doutor João Maximiano street Jandaia do Sul-PR86900-000 Brazil

ISBN: (纸本)9788494392825

The timetabling problem is, as best as possible, allocate teachers at their respective classes, to meet with their students, so that it complies with the amount of weekly lessons of discipline. Many basic education institutions still do this work manually, since commercial softwares to solve this problem are considered high cost, especially for public schools, and softwares available on the web sometimes do not give good solutions. Thus, is demanded a lot of time in the pursuit of meeting the preference of requests from teachers, maybe creating windows, twinned lessons or isolated lessons. In this context, this research seeks to resolve problems such as those mentioned using a metaheuristics and compare the quality of the solution obtained with the use of exact method since metaheuristics admit possible to determine a feasible solution even not getting the optimal solution to the problem. Moreover, the mathematical modeling problem will be penalized the solutions having the undesirable characteristics, increasing the likelihood that the model itself select the solutions with better performance.

关键词： Optimization

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Comparative analysis of adhesive failure of orthodontic resins: An in vitro mechanical test with the finite element method

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European Journal of General Dentistry 2021年第2期2卷 124-129页

作者： Ana Leticia Rocha Avila Mildred Ballin Hecke Ana Paula Gebert de Oliveira Franco Marco Antonio Amorin Vasco Dauro Douglas Oliveira Orlando Motohiro Tanaka Department of Orthodontics School of Health and Biosciences Pontifical Catholic University of Paraná Curitiba Brazil Numerical Methods in Engineering Graduate Program Federal University of Paraná (UFPR) Curitiba Brazil Department of Dentistry Pontifical Catholic University of Paraná Curitiba Brazil Department of Prosthodontics Oral Rehabilitation USP Brazil Department of Orthodontics Pontifical Catholic University of Minas Gerais Belo Horizonte Brazil

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