Browsing Computational Mathematics (CM) by Title
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An IMEX scheme combined with Richardson extrapolation methods for some reactiondiffusion equations
(Idojaras, 20131231)An implicitexplicit (IMEX) method is combined with some socalled Richardson extrapolation (RiEx) methods for the numerical solution of reactiondiffusion equations with pure Neumann boundary conditions. The results are ... 
An IMEX scheme for reactiondiffusion equations: Application for a PEM fuel cell model
(Central European Journal of Mathematics, 20131231)An implicitexplicit (IMEX) method is developed for the numerical solution of reactiondiffusion equations with pure Neumann boundary conditions. The corresponding method of lines scheme with finite differences is analyzed: ... 
Analysis of extreme wave events on the southern coast of Brazil
(Natural Hazards and Earth System Sciences, 20141231)Using the wave model SWAN (simulating waves nearshore), high waves on the southwestern Atlantic generated by extratropical cyclones are simulated from 2000 to 2010, and their impact on the Rio Grande do Sul (RS) coast is ... 
Apparent slip mechanism between two spheres based on solvent rheology: Theory and implication for the shear thinning of nonBrownian suspensions
(Physical Review Fluids, 20181210)Analytical results for the apparent slip between two spheres in a simple biviscous model of a shear thinning fluid are presented. Velocity profiles and apparent slip lengths along the surfaces are analyzed in order to ... 
Arithmetic method of doubleinjectionelectrode model for resistivity measurement through metal casing
(IEEE Transactions on Geoscience and Remote Sensing, 20101231)Throughcasing resistivity (TCR) measurement instruments such as Cased Hole Formation Resistivity are extensively used for the dynamic monitoring of oil reservoirs during the production phase in oil wells to evaluate the ... 
Asymptotic Models for the Electric Potential across a Highly Conductive Casing
(Computers and Mathematics with Applications, 201807)We analyze a configuration that involves a steelcased borehole, where the casing that covers the borehole is considered as a highly conductive thin layer. We develop an asymptotic method for deriving reduced problems ... 
Automatic fitting of conical envelopes to freeform surfaces for flank CNC machining
(Computer Aided Design, 201710)We propose a new algorithm to detect patches of freeform surfaces that can be well approximated by envelopes of a rotational cone under a rigid body motion. These conical envelopes are a preferable choice from the ... 
Automatic RedChannel underwater image restoration
(Journal of Visual Communication and Image Representation, 20151231)Underwater images typically exhibit color distortion and low contrast as a result of the exponential decay that light suffers as it travels. Moreover, colors associated to different wavelengths have different attenuation ... 
BBIPED: BCAMBaltogar Industrial Platform for Engineering Design
(18th International Conference on Circuits, Systems, Communications and Computers (CSCC 2014); Advances in Engineering Mechancis and Materials, Proc.the International Conference; on Industrial Engineering (INDE 2014)", 20141231)Currently, commercial software for computational fluid dynamics offers a good set of features to deal with traditional designs. Within a competitive market industrial innovation is a key factor that must be faced by ... 
Blisk blades manufacturing technologies analysis
(Procedia Manufacturing, 201906)The paper presents blisk blades manufactured by different manufacturing processes. In this sense, different milling trajectories are presented, and, super abrasive machining strategies and EDM technologies are also tested. ... 
Borehole Resistivity Simulations of OilWater Transition Zones with a 1.5D Numerical Solver
(Computational Geosciences volume, 2020)When simulating borehole resistivity measurements in a reservoir, it is common to consider an oilwater contact (OWC) planar interface. However, this consideration can lead to an unrealistic model since in the presence of ... 
A C 0 interior penalty discontinuous Galerkin Method for fourthorder total variation flow. II: Existence and uniqueness
(NMPDE:Numerical Methods For Partial Differential Equations, 20190225)We prove the existence and uniqueness of a solution of a C0 Interior Penalty Discontinuous Galerkin (C0 IPDG) method for the numerical solution of a fourth‐order total variation flow problem that has been developed in part ... 
A C0 interior penalty discontinuous Galerkin method for fourth‐order total variation flow I: Derivation of the method and numerical results
(NMPDE:Numerical Methods For Partial Differential Equations, 20190223)We consider the numerical solution of a fourth‐order total variation flow problem representing surface relaxation below the roughening temperature. Based on a regularization and scaling of the nonlinear fourth‐order parabolic ... 
Computation of slat noise sources using adaptive FEM and lighthill's analogy
(19th AIAA/CEAS Aeroacoustics Conference, 20131231)This is a summary of preliminary results from simulations with the 30P30N highlift device. We used the General Galerkin finite element method (G2), where no explicit subgrid model is used, and where the computational mesh ... 
Computational cost estimates for parallel shared memory isogeometric multifrontal solvers
(Computers and Mathematics with Applications, 20141231)In this paper we present computational cost estimates for parallel shared memory isogeometric multifrontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as $\mathcal{O}( ... 
Computational cost of isogeometric multifrontal solvers on parallel distributed memory machines
(Computer Methods in Applied Mechanics and Engineering, 20151231)This paper derives theoretical estimates of the computational cost for isogeometric multifrontal direct solver executed on parallel distributed memory machines. We show theoretically that for the $C^{p1}$ global continuity ... 
Computational fixedpoint theory for differential delay equations with multiple time lags
(Journal of Differential Equations, 20121231)We introduce a general computational fixedpoint method to prove existence of periodic solutions of differential delay equations with multiple time lags. The idea of such a method is to compute numerical approximations of ... 
Control of distributed parameter systems modelled by parabolic variational inequalities of the obstacle type
(2019)We will investigate the numerical solution of the control problem modelled by parabolic variational inequalities. The general point of view adopted in this work has its roots in the work by R. Glowinski. The optimal control ... 
A Deep Learning Approach to the Inversion of Borehole Resistivity Measurements
(Computational Geosciences volume, 202004)Borehole resistivity measurements are routinely employed to measure the electrical properties of rocks penetrated by a well and to quantify the hydrocarbon pore volume of a reservoir. Depending on the degree of geometrical ... 
A Deep Neural Network as Surrogate Model for Forward Simulation of Borehole Resistivity Measurements
(Procedia Manufacturing, 202001)Inverse problems appear in multiple industrial applications. Solving such inverse problems require the repeated solution of the forward problem. This is the most timeconsuming stage when employing inversion techniques, ...