• 제목/요약/키워드: fully discrete approximation

검색결과 13건 처리시간 0.019초

ERROR ESTIMATES OF FULLY DISCRETE DISCONTINUOUS GALERKIN APPROXIMATIONS FOR LINEAR SOBOLEV EQUATIONS

  • Ohm, M.R.;Shin, J.Y.;Lee, H.Y.
    • Journal of applied mathematics & informatics
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    • 제27권5_6호
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    • pp.1221-1234
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    • 2009
  • In this paper, we construct fully discrete discontinuous Galerkin approximations to the solution of linear Sobolev equations. We apply a symmetric interior penalty method which has an interior penalty term to compensate the continuity on the edges of interelements. The optimal convergence of the fully discrete discontinuous Galerkin approximations in ${\ell}^{\infty}(L^2)$ norm is proved.

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FULLY DISCRETE MIXED FINITE ELEMENT METHOD FOR A QUASILINEAR STEFAN PROBLEM WITH A FORCING TERM IN NON-DIVERGENCE FORM

  • Lee, H.Y.;Ohm, M.R.;Shin, J.Y.
    • Journal of applied mathematics & informatics
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    • 제24권1_2호
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    • pp.191-207
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    • 2007
  • Based on a mixed Galerkin approximation, we construct the fully discrete approximations of $U_y$ as well as U to a single-phase quasilinear Stefan problem with a forcing term in non-divergence form. We prove the optimal convergence of approximation to the solution {U, S} and the superconvergence of approximation to $U_y$.

L2-ERROR ANALYSIS OF FULLY DISCRETE DISCONTINUOUS GALERKIN APPROXIMATIONS FOR NONLINEAR SOBOLEV EQUATIONS

  • Ohm, Mi-Ray;Lee, Hyun-Young
    • 대한수학회보
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    • 제48권5호
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    • pp.897-915
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    • 2011
  • In this paper, we develop a symmetric Galerkin method with interior penalty terms to construct fully discrete approximations of the solution for nonlinear Sobolev equations. To analyze the convergence of discontinuous Galerkin approximations, we introduce an appropriate projection and derive the optimal $L^2$ error estimates.

ERROR ESTIMATES FOR FULLY DISCRETE DISCONTINUOUS GALERKIN METHOD FOR NONLINEAR PARABOLIC EQUATIONS

  • Ohm, Mi-Ray;Lee, Hyun-Yong;Shin, Jun-Yong
    • Journal of applied mathematics & informatics
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    • 제28권3_4호
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    • pp.953-966
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    • 2010
  • In this paper, we develop discontinuous Galerkin methods with penalty terms, namaly symmetric interior penalty Galerkin methods to solve nonlinear parabolic equations. By introducing an appropriate projection of u onto finite element spaces, we prove the optimal convergence of the fully discrete discontinuous Galerkin approximations in ${\ell}^2(L^2)$ normed space.

MIXED FINITE ELEMENT APPROXIMATION OF A STEFAN PROBLEM

  • Shin, Jun-Yong
    • Journal of applied mathematics & informatics
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    • 제11권1_2호
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    • pp.357-364
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    • 2003
  • A fully discrete $H^1-mixed$ finite element approximation for the single-phase Stefan problem is introduced and the unique existence of the approximation is established. And some numerical experiments are given.

ERROR ANALYSIS OF FINITE ELEMENT APPROXIMATION OF A STEFAN PROBLEM WITH NONLINEAR FREE BOUNDARY CONDITION

  • Lee H.Y.
    • Journal of applied mathematics & informatics
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    • 제22권1_2호
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    • pp.223-235
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    • 2006
  • By applying the Landau-type transformation, we transform a Stefan problem with nonlinear free boundary condition into a system consisting of a parabolic equation and the ordinary differential equations. Fully discrete finite element method is developed to approximate the solution of a system of a parabolic equation and the ordinary differential equations. We derive optimal orders of convergence of fully discrete approximations in $L_2,\;H^1$ and $H^2$ normed spaces.

UNCONDITIONAL STABILITY AND CONVERGENCE OF FULLY DISCRETE FEM FOR THE VISCOELASTIC OLDROYD FLOW WITH AN INTRODUCED AUXILIARY VARIABLE

  • Huifang Zhang;Tong Zhang
    • 대한수학회지
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    • 제60권2호
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    • pp.273-302
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    • 2023
  • In this paper, a fully discrete numerical scheme for the viscoelastic Oldroyd flow is considered with an introduced auxiliary variable. Our scheme is based on the finite element approximation for the spatial discretization and the backward Euler scheme for the time discretization. The integral term is discretized by the right trapezoidal rule. Firstly, we present the corresponding equivalent form of the considered model, and show the relationship between the origin problem and its equivalent system in finite element discretization. Secondly, unconditional stability and optimal error estimates of fully discrete numerical solutions in various norms are established. Finally, some numerical results are provided to confirm the established theoretical analysis and show the performances of the considered numerical scheme.

ESTRPOLATED CRANK-NICOLSON APPROXIMATION FOR A LINEAR STEFAN PROBLEM WITH A FORCING TERM

  • Ahn, Min-Jung;Lee, Hyun-Young
    • Journal of applied mathematics & informatics
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    • 제8권3호
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    • pp.795-809
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    • 2001
  • In this paper, we apply finite element Galerkin method to a single-ohase linear Stefan problem with a forcing term. We apply the extrapolated Crank-Nicolson method to construct the fully discrete approximation and we derive optimal error estimates in the temporal direction in $L^2$, $H^1$ spaces.

Meshfree consolidation analysis of saturated porous media with stabilized conforming nodal integration formulation

  • Wang, Dongdong;Xie, Pinkang;Lu, Hongsheng
    • Interaction and multiscale mechanics
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    • 제6권2호
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    • pp.107-125
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    • 2013
  • A strain smoothing meshfree formulation with stabilized conforming nodal integration is presented for modeling the consolidation process in saturated porous media. In the present method, nodal strain smoothing is consistently introduced into the meshfree approximation of strain and pore pressure gradient variables associated with the saturated porous media. Meanwhile, in order to achieve a consistent numerical implementation, a smoothing approximation of the meshfree shape function within a nodal representative domain is also proposed in the stiffness construction. The resulting discrete system of equations is all expressed in smoothed nodal measures that are very efficient for numerical evaluation. Subsequently the space-time fully discrete equations are further established by the generalized trapezoidal rule for time integration. The effectiveness of the proposed meshfree consolidation analysis method is systematically illustrated by several benchmark problems.