• Communications of the Korean Mathematical Society
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• v.12 no.2
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• pp.467-478
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• 1997

A nonlinear Galerkin method for the Burgers equation is considered. Due to the lack of the divergence free condition, the nonlinear term is treated differently compared to that of the Navier-Stokes equations. Strong convergence results are proved for the nonlinear Galerkin method.

• Communications of the Korean Mathematical Society
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• v.10 no.4
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• pp.981-995
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• 1995

This paper first establishes some conditions for preconditioner under which PGCR does not break down. Next, VPGCR algorithm whose preconditioners can be easily obtained is introduced and then its breakdown and convergence properties are discussed. Lastly, implementation details of VPGCR are described and then numerical results of VPGCR with a certain criterion guaranteeing no breakdown are compared with those of restarted GMRES.

• Journal of applied mathematics & informatics
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• v.36 no.3_4
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• pp.257-270
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• 2018

An extrapolated Crank-Nicolson characteristic finite element method is introduced for approximate solutions of nonlinear Sobolev equations with a convection term. And we obtain the higher order of convergence for approximate solutions in the temporal and the spatial directions with respect to $L^2$ norm.

• Communications of the Korean Mathematical Society
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• v.21 no.2
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• pp.237-251
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• 2006

In this paper, we introduce and study a new iterative algorithm for approximating zeroes of accretive operators in Banach spaces.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.08a
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• pp.5-8
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• 2000

This paper introduced a scheme for finding an optimal association matrix that represents the relationships between the measurements and tracks in multi-target tracking of Radar system. We considered the relationships between targets and measurements as MRF and assumed a priori of the associations as a Gibbs distribution. Based on these assumptions, it was possible to reduce the MAP estimate of the association matrix to the energy minimization problem. After then, we defined an energy function over the measurement space, that may incorporate most of the important natural constraints.

• Journal of Microbiology and Biotechnology
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• v.32 no.12
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• pp.1632-1632
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• 2022

• East Asian mathematical journal
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• v.25 no.2
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• pp.141-146
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• 2009

In this paper, we introduce a new generalized nonlinear quasivariational inequality and establish its equivalence with a xed point problem by using the resolvent operator technique. Utilizing this equivalence, we suggest two iterative schemes, prove two existence theorems of solutions for the generalized nonlinear quasivariational inequality involving generalized cocoercive mapping and establish some convergence results of the sequences generated by the algorithms. Our results include several previously known results as special cases.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.541-547
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• 2017

Climate change has become the main cause of the exacerbation in natural disasters. Social Overhead Capital(SOC) structure needs to be checked for displacement and crack periodically to prevent damage and the collapse caused by natural disaster and ensure the safety. For efficient structure maintenance, the optical image technology is applied to the Structure Health Monitoring(SHM). However, optical image is sensitive to environmental factors. So it is necessary to verify its validity. In this paper, the accuracy of estimating the vertical displacement was verified with respect to environmental condition such as natural light, measurement distance, and the number of image sheets. The result of experiments showed that the effect of natural light on accuracy of estimating vertical displacement was the greatest of all. The measurement angle which was affected by the change in measurement distance was also important to check the vertical displacement. These findings will be taken into account by applying appropriate environmental condition to minimize errors when the bridge was measured by camera. It will also enable the application of optical images to the SHM.

• Journal of Life Science
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• v.31 no.8
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• pp.745-754
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• 2021

Deterioration of the immune function weakens the body's resistance to various infections, leading to a series of diseases. Immunomodulatory biomaterials have been used to reduce the side effects of immunosuppressants or to enhance immunity. Agarwood is the aromatic resinous portion of Aquilaria trees that has been traditionally used as a medicinal herb for the treatment of various diseases. Although previous studies have shown that agarwood can improve the body's immunity, evidence for this claim is still lacking. In this study, the immune-enhancing effects of the agarwood methanol extracts of Aquilaria malaccensis Lamk were evaluated in a RAW 264.7 macrophage model. Based on the results, the agarwood extracts markedly enhanced phagocytosis in the absence of cytotoxicity. The agarwood extract-treated RAW 264.7 cells exhibited the typical morphology of activated macrophages, which are spindle-shaped with elongated filopodia. Agarwood extract also significantly increased the production of nitric oxide (NO), which is associated with the increased expression of inducible NO synthase. Moreover, the secretion and expression levels of cytokines, such as tumor necrosis factor-α and interleukin (IL)-1β and IL-6, were increased by agarwood treatment. Notably, these are also associated with a mitogen-activated protein kinase signaling pathway. Taken together, our findings provide scientific evidence that agarwood has potential immune-enhancing effects in vitro.

• Communications of the Korean Mathematical Society
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• v.20 no.4
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• pp.709-721
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• 2005