# LEAST-SQUARES SPECTRAL COLLOCATION PARALLEL METHODS FOR PARABOLIC PROBLEMS

• SEO, JEONG-KWEON (Department of Mathematics, Chonnam National University) ;
• SHIN, BYEONG-CHUN (Department of Mathematics, Chonnam National University)
• Accepted : 2015.05.29
• Published : 2015.09.25
• 93 13

#### Abstract

In this paper, we study the first-order system least-squares (FOSLS) spectral method for parabolic partial differential equations. There were lots of least-squares approaches to solve elliptic partial differential equations using finite element approximation. Also, some approaches using spectral methods have been studied in recent. In order to solve the parabolic partial differential equations in parallel, we consider a parallel numerical method based on a hybrid method of the frequency-domain method and first-order system least-squares method. First, we transform the parabolic problem in the space-time domain to the elliptic problems in the space-frequency domain. Second, we solve each elliptic problem in parallel for some frequencies using the first-order system least-squares method. And then we take the discrete inverse Fourier transforms in order to obtain the approximate solution in the space-time domain. We will introduce such a hybrid method and then present a numerical experiment.

#### Keywords

first-order least-squares method;parabolic equation;Fourier transform

#### Acknowledgement

Supported by : Chonnam National University

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