• Journal of applied mathematics & informatics
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• v.33 no.1_2
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• pp.33-44
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• 2015

The convergence rate of a numerical procedure based on Schwarz Alternating Method(SAM) for solving elliptic boundary value problems depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It has been observed that the Robin condition (mixed interface condition), controlled by a parameter, can optimize SAM's convergence rate. In [7], one formulated the multi-parameterized SAM and determined the optimal values of the multi-parameters to produce the best convergence rate for one-dimensional elliptic boundary value problems. Two-dimensional implementation was presented in [8]. In this paper, we present an implementation for three-dimensional problem.

• Journal of applied mathematics & informatics
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• v.9 no.1
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• pp.101-124
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• 2002

The convergence rate of a numerical procedure barred on Schwarz Alternating Method (SAM) for solving elliptic boundary value problems (BVP's) depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It hee been observed that the Robin condition(mixed interface condition), controlled by a parameter, can optimize SAM's convergence rate. Since the convergence rate is very sensitive to the parameter, Tang[17] suggested another interface condition called over-determined interface condition. Based on the over-determined interface condition, we formulate the two-layer multi-parameterized SAM. For the SAM and the one-dimensional elliptic model BVP's, we determine analytically the optimal values of the parameters. For the two-dimensional elliptic BVP's , we also formulate the two-layer multi-parameterized SAM and suggest a choice of multi-parameter to produce good convergence rate .

• Biomedical Science Letters
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• v.27 no.2
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• pp.99-104
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• 2021

Treatment techniques that affect homeostasis by non-invasive regulation in peripheral organs will advance disease research. Here, we demonstrate a non-invasive method of conditioning within an organ using a low-frequency stimulator superposition of alternating microcurrent wave in stages. It is first applied to the inflammatory response in H3N2-infected sinusitis mice. To check the progress of the treatment, mice were sacrificed every week for 3 weeks, nasal tissue was removed, and the inflammatory response was investigated through H & E staining. The low-frequency stimulation treatment group was found to alleviate the proliferation of epithelial cells and invasion of inflammatory cells compared to the control group as the passage of treatment time. The reduction of inflammatory cytokines in the nasal lavage fluid was observed in H3N2-infected sinusitis mice treated with of low-frequency stimulation using superposition of alternating microcurrent wave compared to H3N2-infected sinusitis mice after 3 weeks. These data demonstrate that low-frequency stimulation device in the form of using alternating current wave superposition on within organs provides a new method to regulate specific physiological functions. Therefore, it is necessary to prove the inhibitory effect of low-frequency stimulation using alternating current wave superposition on inflammatory diseases by various methods through further studies and clinical studies.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1431-1432
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• 2013

• Macromolecular Research
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• v.11 no.6
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• pp.437-443
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• 2003

A series of alternating and alternating block copolycarbonates containing the constituent groups of polysulfone was synthesized through a multi-step solution condensation method. For the regulation of block length, monodisperse oligomers were prepared by using a large excess of the bisphenols and were subsequently incorporated into the copolymer chains. Separating the unreacted bisphenols from the oligomers by dissolution/precipitation steps took advantage of solubility differences. The structures of the monomers, oligomers, and copolymers were characterized and confirmed by GPC, NMR spectroscopy, mass spectrometry, and elemental analysis. Monodispersity of the oligomers, which is critical for control over the block length in the copolymers, was confirmed by GPC and mass spectrometry. Of the two constituent groups of the polysulfone, the sulfone linkage stiffens the polycarbonate copolymer chain, while the ether linkage softens it.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.111-114
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• 2003

In order to improve the surface uniformity and the conduction properties of the fabricated YBCO thick films, a system that applies alternating field vertically to the EPD field has been developed for the first time and applied to the electrophoretic deposition process. The applied alternating electric field caused a force to be exerted on each YBCO particle and resulted in a shaking of the particle in the direction of applied electric field, accomplishing a uniform particle orientation. The usual commercial electrical power was used for the vertically applied alternating voltage and the induced electric field was 25-120 V/cm at 60Hz. The thick film fabricated by the method developed in this paper showed better surface uniformity without crack and porosity and improved film characteristics such as critical temperature ($T_{c,zero}$ : 90 K) and critical current density ($2354\;A/cm^2$). Therefore, it is expected that the shaky-aligned electrophoretic deposition method can be used to fabricate superconductor films through a simpler process and at less expense.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.1
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• pp.9-17
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• 2001

A numerical study has been carried out on the evolution of the particle size distribution for unipolar charged particles that experience coagulation in an alternating electric field. The collision frequency function of charged particles was analytically derived. The log-normal size distribution function is utilized for representing a poly-disperse size distribution and the moments of the particle size distribution are used to solve the general dynamic equation considering only AC electric force effect. The results are compared with the effects of brownian coagulation.

• Journal of Korea Game Society
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• v.10 no.4
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• pp.81-90
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• 2010

In this paper, an efficient method is proposed to produce photorealistic images of woven fabrics without empirical data such as the measured BRDFs(bidirectional reflectance distribution functions). The proposed method is applicable both to ray tracer based offline renderers and to realtime applications such as games. The proposed method models the reflectance properties of woven fabric with alternating anisotropy and deformed MDF(microfacet distribution function). The procedural modeling of the yarn structure effectively and efficiently reproduces plausible rendering of woven fabric. The experimental results show the proposed method can be successfully applied to photorealistic rendering of diverse woven fabric materials even in interactive applications.

• Journal of IKEEE
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• v.19 no.3
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• pp.366-370
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• 2015

This paper proposes an alternating battery discharge method by balancing discharge time of battery cells, which significantly increases battery lifetime. In the conventional method, several battery cells are alternately discharged to make battery recovery effect, and this increases battery lifetime. In this case, there are some overlap intervals where several battery cells are ON to avoid system power cut-off, but this makes several problems due to the voltage differences of battery cells. To mitigate these problems, discharge time of battery cells are controlled to make battery cell voltages as equal as possible. Measurements show that the battery lifetime is exxtended by 19.2% in the proposed method.

• Journal of the Korean Vacuum Society
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• v.14 no.1
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• pp.24-28
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• 2005

A typical method for obtaining poly-Si films is the solid phase crystallization(SPC) of amorphous Si. Advantages of SPC are uniformity, process quality and low cost of production. However, high process temperature and long process time prevent the employment of SPC process on thermally susceptible glass substrate. In this parer, we propose a new method that applies an alternating magnetic field during crystallization annealing in an alternating magnetic field crystallization(AMFC) system for lowering process temperature and shorter process time of SPC. When we crystallized, in the case of SPC, annealing time is 24 hours at 570℃. But in the case of AMFC, annealing time is only 20 minutes at the same temperature.