• Journal of computational fluids engineering
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• v.10 no.4 s.31
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• pp.12-17
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• 2005

A computational study of evaluation of current turbulence models is performed for a better prediction of thermal stratification in an upper plenum of a liquid metal reactor. The turbulence models tested in the present study are the two-layer model, the shear stress transport (SST) model, the v2-f model and the elliptic blending mode(EBM). The performances of the turbulence models are evaluated by applying them to the thermal stratification experiment conducted at JNC (Japan Nuclear Corporation). The algebraic flux model is used for treating the turbulent heat flux for the two-layer model and the SST model, and there exist little differences between the two turbulence models in predicting the temporal variation of temperature. The v2-f model and the elliptic blending model better predict the steep gradient of temperature at the interface of thermal stratification, and the v2-f model and elliptic blending model predict properly the oscillation of the ensemble-averaged temperature. In general the overall performance of the elliptic blending model is better than the v2-f model in the prediction of the amplitude and frequency of the temperature oscillation.

• Journal of the Korean Geotechnical Society
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• v.30 no.11
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• pp.17-23
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• 2014

In this study, the prognostic model for the prediction of the road surface temperature is developed using the surface energy balance theory. This model not only has a detailed micro meteorological physical attribute but also is able to accurately represent each surface energy budget. To verify the performance, the developed model output was compared with the German Weather Service (DWD)'s Energy Balance Model (EBM) output, which is based on the energy budget balance theory, and the observations. The simulated results by using both models are very similar to each other and are compatible with the observed data.

• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.111-117
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• 2008

This paper reports briefly on the computational results of a turbulent Rayleigh-Benard convection with the elliptic-blending second-moment closure (EBM). The primary emphasis of the study is placed on an investigation of accuracy and numerical stability of the elliptic-blending second-moment closure for the turbulent Rayleigh-Benard convection. The turbulent heat fluxes in this study are treated by the algebraic flux model with the temperature variance and molecular dissipation rate of turbulent heat flux. The model is applied to the prediction of the turbulent Rayleigh-Benard convection for Rayleigh numbers ranging from $Ra=2{\times}10^6$ to $Ra=10^9$, and the computed results are compared with the previous experimental correlations, T-RANS and LES results. The predicted cell-averaged Nusselt number follows the correlation by Peng et al.(2006) ($Nu=0.162Ra^{0.286}$) in the 'soft' convective turbulence region ($2{\times}10^6{\leq}Ra{\leq}4{\times}10^7$) and it follows the experimental correlation by Niemela et al. (2000) ($Nu=0.124Ra^{0.309}$) in the 'hard' convective tubulence region ($10^8{\leq}Ra{\leq}10^9$) within 5% accuracy. This results show that the elliptic-blending second-moment closure with an algebraic flux model predicts very accurately the Rayleigh Benard convection.

• Journal of computational fluids engineering
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• v.13 no.3
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• pp.62-68
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• 2008

This paper reports briefly on the computational results of a turbulent Rayleigh-Benard convection with the elliptic-blending second-moment closure (EBM). The primary emphasis of the study is placed on an investigation of accuracy and numerical stability of the elliptic-blending second-moment closure for the turbulent Rayleigh-Benard convection. The turbulent heat fluxes in this study are treated by the algebraic flux model with the temperature variance and molecular dissipation rate of turbulent heat flux. The model is applied to the prediction of the turbulent Rayleigh-Benard convection for Rayleigh numbers ranging from Ra=$2{\times}10^6$ to Ra=$10^9$ and the computed results are compared with the previous experimental correlations, T-RANS and LES results. The predicted cell-averaged Nusselt number follows the correlation by Peng et al.(2006) (Nu=$0.162Ra^{0.286}$) in the 'soft' convective turbulence region ($2{\times}10^6{\leq}Ra{\leq}4{\times}10^7$) and it follows the experimental correlation by Niemela et al. (2000) (N=$0.124Ra^{0.309}$) in the 'hard' convective turbulence region ($10^8{\leq}Ra{\leq}10^9$) within 5% accuracy. This results show that the elliptic-blending second-moment closure with an algebraic flux model predicts very accurately the Rayleigh-Benard convection.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.934-937
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• 2005

It is not efficient and scarcely out of the question to use commercial expensive electron beam lithography system widely used for semiconductor fabrication process for the manufacturing application field of various devices in the small business scope. Then scanning electron microscope based electron beam machining system is maybe regarded as a powerful model can be used for it simply. To get a complete suite of thus proper system, proper chamber with high vacuum condition is necessarily required more than anything else to modify scanning electron microscope. In this study, special chamber unit using rotary pump and diffusion pump to obtain high vacuum degree was designed and manufactured and various evaluation tests fur recognize the vacuum characteristic were accomplished.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.2
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• pp.125-151
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• 2008

Purpose: In this study, we investigated the anti-thrombotic efficacy of "Eungapbang-gagam(EGB)" currently used in clinical treatment of PID Methods: We studied inhibitory effect of platelet cohesion, suppressive effect of GPIIb/IIIa activity, inhibitory effect of $TXB_2$ and $PGE_2$ biosynthesis, and oxidative damage suppression effects of "EGB" in vitro. Also, suppression of pulmonary embolism and changes of related factors in dextran coagulation condition model were studied in vivo. Results: In this study, EGB extract showed dose-dependent inhibitory effect on platelet coagulation induced by ADP, epinephrine, collagen, arachidonic acid. Also it showed dose-dependent inhibition effect on GPIIb/IIIa activities compared to the control group. EGB extract significantly suppressed the decrease of speed of bloodstream caused by blood coagulation in dextran coagulation condition model and increased the number of platelets and amount of fibrinogen, and decreased the APTT in dextran coagulation condition model compared to the control group. EGB extract showed dose-dependent decrease of oxidative damages caused by DPPH and superoxide anion radicals, whereas dose-dependent increase of superoxide dismutase like activity was observed compared to the control group. Conclusion: We confirmed the anti-thrombosis and anti-oxidative efficacy of "Eungapbang-gagam". Various clinical applications of "Eungapbang-gagam" as well as use of data for the construction of EBM is anticipated.

• Journal of Haehwa Medicine
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• v.17 no.2
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• pp.69-86
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• 2008

In order to validate the objective efficacy of CBPT on anti-asthma and to develop effective therapeutics for asthma treatments, immunological modulatory mechanism was studied using animal model using OVA-Alum. The results are listed below. When treated with CBPT, survival rate of hFCs at 250 ug/ml was above 90%. AST and ALT, indicators of liver function measurements were in the normal range. Compared to the control group, CBPT treated group showed significant reduction in liver weights at both 400 and 200 mg/kg, and significant decrease of total liver cells at 400 mg/kg. Significant increase in CD4+ and CD8+ cells in DLN was observed in the CBPT treated group. Slight increase in CD3+, CD4+/CD25+ cells were also observed. On the other hand, CBPT significantly reduced the CD3+/CD69+ cell numbers at both concentrations. Slight decrease of CD19+ cells was also observed. CBPT significantly reduced the CD3e+/CD69+, CCR3+ and CD11b+/Gr-1+ cells in lung tissues at both doses. However, significant decrease of CD3e+ and B220+/IgE+ cells was only observed at 400 mg/kg dosed group. The results above strongly suggest the anti-asthmatic effect of CBPT through immunological modulation. By using various concentrations of CBPT, broader clinical applications of CBPT on anti-asthmatic treatment can be developed. The EBM database should provide valuable information in the development of drugs for asthma treatments.

• Journal of Haehwa Medicine
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• v.21 no.1
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• pp.53-63
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• 2012

Objectives : The aim of this study was to investigate the effect of Chunghwatang (CHT) for atopic dermatitis. Methods : CHT, a verified anti-oxidant and anti-inflammatory effect, was treated in atopic dermatitis animal model to investigate cytokine levels and immunoglobulin production. Results : Clinical skin index was 47.1%, suggesting significant efficacy of CHT in atopic dermatitis treatment. Serum IL-4, IL-6, IL-13, TNF-${\alpha}$ and histamine productions were significantly decreased to 52.3%, 61.8%, 68.0%, 37.4%, and 46.6%, respectively. The production of IL-5 was decreased to 33.3%. The increase of Immunoglobulin IgG1 production along with IgE through the interaction of IgE and IL-4 induced by IL-4 and IL-13 were measured as 20.7% and 23.4%, respectively. Conclusions : The results above, along with the in vitro test results, strongly supports the CHT samples as effective immunomodulator in AD treatments, suggesting its use in clinical practice and basic information for EBM.

• Journal of International Society for Simulation Surgery
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• v.1 no.1
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• pp.13-15
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• 2014

Nowadays, with advanced 3D printing techniques, the custom-made implant can be manufactured for the patient. Especially in skull reconstruction, it is difficult to design the implant due to complicated geometry. In large defect, an autograft is inappropriate to cover the defect due to donor morbidity. We present the process of manufacturing the 3D custom-made implant for skull reconstruction. There was one patient with skull defect repaired using custom-made 3D titanium implant in the plastic and reconstructive surgery department. The patient had defect of the left parieto-temporal area after craniectomy due to traumatic subdural hematoma. Custom-made 3D titanium implants were manufactured by Medyssey Co., Ltd. using 3D CT data, Mimics software and an EBM (Electron Beam Melting) machine. The engineer and surgeon reviewed several different designs and simulated a mock surgery on 3D skull model. During the operation, the custom-made implant was fit to the defect properly without dead space. The operative site healed without any specific complications. In skull reconstruction, autograft has been the treatment of choice. However, it is not always available and depends on the size of defect and donor morbidity. As 3D printing technique has been advanced, it is useful to manufacture custom-made implant for skull reconstruction.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.4
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• pp.446-454
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• 2012

In order to evaluate the efficacy of SHT against atopic dermatitis (AD), various immune related cytokines as well as histological comparison were performed in animal models, and the results are described. Clinical skin index of the SHT treated group decreased significantly in weeks 11 and 13, compared to the control group. Also, CD4+ immune cell ratio in the dorsal skin was significantly decreased to 69%, and both epidermal and dermal skin thickness was decreased. Serum IL-4, IL-5, IL-6, IL-13, and TNF-${\alpha}$, which are all important markers of inflammation, were decreased to 64%, 44%, 87%, 48%, and 45%, respectively. The expression of histamine, a chemical transmitter increasingly released during the progression of inflammation, was significantly decreased to 47%. The production of IgE immunoglobulin was significantly decreased to 16% compared to the control group. In conclusion, SHT pacifies the activation of T cells, leading to suppression of both Th2 cytokine overexpression and infiltration of immune cells into skin. As a result, relative thinning of both epidermis and dermis were observed. With the results obtained from in vitro studies, the immune modulatory effect of SHT in AD animal models was experimentally demonstrated. This study should provide solid information to construct EBM and for clinical practice.