• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1279-1282
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• 2005

본 논문은 초고속 전송을 위해 설계된 HCOC(High Capacity Orthogonal Code) 기술을 적용한 Multi-Code Spread Spectrum System에서 발생할 수 있는 PAPR(Peck to Average power Ratio) 문제해결을 위한 연구이다. H(HCOC)MC-SS 시스템의 PAPR 감소를 위해 기본적인 SLM(Selected Mapping) 기법을 적용하였으며, 또한 SLM 기법의 단점인 많은 계산량 감소를 위해 Recursive 방법을 적용한 Recursive SLM HMC-SS 시스템을 제안하였다. 컴퓨터 시뮬레이션을 통해 제안하는 시스템을 검증하였으며, 또한 초고속 전송을 위한 16 QAM-SS 시스템과 $4{\times}4$ HMC-SS 시스템의 성능을 비교 분석하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.16-21
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• 2002

The high speed machining center(HMC) has been widely applied to manufacture a die and trial product in many machine industry. Because the evaluation fer the HMC is not sufficiently performed and the efficient cutting conditions aren't selected, a great loss has been caused in the cost aspect. In this study, the need of preliminary running time and unstable spindle speed is presented from the analysis of acceleration in idling. The Machinability fur the TiAlN coated flat end mill and STD11( $H_{R}$C60) is evaluated from the trends of tool wear and cutting force according to cutting conditions and slenderness ratio and a low response of tool dynamometer in high speed is proved. The resonance spindle speed is identified through the tool wear and natural frequency test.t.

• Natural Product Sciences
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• v.17 no.3
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• pp.239-244
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• 2011

Immediate-type hypersensitivity is involved in many allergic diseases such as asthma, allergic rhinitis and anaphylaxis. The discovery of drugs for the treatment of allergic disease is an important subject in human health. Stimulation of mast cells releases inflammatory mediators, such as histamine and pro-inflammatory cytokines with immune regulatory properties. We investigated the effect of the aqueous extract of Schizonepeta tenuifolia (AEST) (Labiatae) on the immediate-type allergic reaction. AEST inhibited compound 48/80-induced systemic allergic reaction. AEST attenuated immunoglobulin E (IgE)-mediated skin allergic reaction and histamine release from human mast cell line (HMC-1) cells. In addition, AEST decreased the gene expression and secretion of pro-inflammatory cytokines in phorbol 12-myristate 13-acetate (PMA) plus calcium ionophore A23187 (A23187)-stimulated HMC-1 cells. Our results indicate that AEST inhibits the mast cell-derived allergic reactions and involvement of histamine and pro-inflammatory cytokines in these effects.

• Journal of Haehwa Medicine
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• v.13 no.2
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• pp.123-129
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• 2004

We observed the efficacy of natural herbs and mixture in treating atopic dermatitis using anti-human IgE treated Human HMC-I cell model. We selected three herbs, Cynonchum witfordii, Diospyros kaki, Ilite which were used to treat skin disease in Traditional Korea Medicine. Using Human HMC-I cell treated with anti-human IgE, we investigate in vitro whether each herb effects on IL-4, IL-13, TNF-a expression and TNF-a, Histamine secretion value. The results show the possibility that the mixture of three herbs may be better in improving atopic dermatitis condition.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.456-461
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• 2002

Nowadays, there are required more speed and accurate machining in order to improve the productivity through the reduction of cutting and non-cutting time. In this study, the high-speed HMC is specially designed to do remote control and high-speed mechanism with 30000rpm, 50000rpm, 40m/min, 100m/min and bridge type structure. Every structural deformation and vibration that is generated from all of factor is analyzed being based on the virtual manufacturing technologies: thermal characteristic analysis, machine-ability, tool wear measuring system, driving characteristic of linear motor and so on. As the application of these results had been consisted of three axes to move slight and rigid finally. Therefore, table errors that are resulted in change of work weight can be removed.

• Biomedical Science Letters
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• v.24 no.4
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• pp.349-356
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• 2018

Generally, berry fruits have various pharmacological activities such as anti-inflammation, anti-oxidation and anti-cancer effects. The effects of gooseberry, a berry fruits, on atopic dermatitis (AD) have not been widely examined. The aim of this present study is to investigate whether gooseberry modulates AD. We examined the pharmacological effects of gooseberry on 2, 4-dinitrochlorobenzene (DNCB)-induced AD symptoms in mice. To determine the anti-atopic mechanism of gooseberry, we investigated its effects on the production of inflammatory cytokines and activation of nuclear factor-${\kappa}B$ in PMA + ionophore -stimulated human mast cells (HMC-1). The results demonstrated that gooseberry attenuated AD clinical symptoms such as erythema, edema and dryness as well as histamine and IgE serum levels in DNCB-induced AD model mice. Additionally, gooseberry suppressed the expression of inflammatory cytokines and activation of nuclear factor-${\kappa}B$ in stimulated HMC-1. These findings demonstrate that gooseberry is potential agent for treating AD and allergic inflammation.

• Korean Journal of Plant Resources
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• v.36 no.6
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• pp.549-555
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• 2023

Hijikia fusiforme (HF), a member of brown algae family, exerts various pharmacological effects, including preventing arteriosclerosis and menopausal disorders. This study aimed to elucidate the ameliorative effect of HF on skin inflammation. We investigated the antioxidant and anti-inflammatory effect of HF extract to evaluate its potential as a functional materials. The antioxidant activity of HF was determined using 2,2-diphenyl-1-picrylhydrazy (DPPH) scavenging and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) scavenging. To determine the pharmacological mechanism of HF in inflammatory reaction, we evaluated the effects of HF on interleukin (IL)-8, IL-6 and tumor necrosis factor (TNF)-α production and nuclear factor-κB (NF-κB) activation in activated- human mast cells (HMC)-1. Results showed that HF had the high DPPH and ABTS+ radical scavenging activity, and it suppressed IL-8, IL-6 and TNF-α production in a concentration-dependent manner. Moreover, HF significantly ameliorated NF-kB activation in activated-HMC-1. Hence, these results provide evidence that HF's potential for skin inflammation therapy.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.41-49
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• 2009

Soeumin-Googwihyangso-san(SGGHSS) has been used for the prevention or treatment of Soeumin-allergic rhinitis. This study was performed to demonstrate anti-allergic and anti-inflamatory effects of SGGHSS methanol extract in HMC cell lines and activated mouse B cells and CD4+ T cells. SGGHSS inhibited the production of TNF-$\alpha$ in PMA plus A23187 activated HMC-1 cells but not that of IL-6, as measured by ELISA. SGGHSS inhibited the expression of CD23 and surface IgE in B cells as determined by flowcytometry. It also inhibited secretion of IFN-$\gamma$ and IgG1, the Th1 related IgG type, but increased that of IL-4 in anti-CD40 and IL-4 treated B cells as measured by ELISA. As for Th cell differentiation, SGGHSS did not much affect IL-4 or IFN-$\gamma$. Taken together, our data showed that SGGHSS exerted an anti-inflammtory effect by inhibiting TNF-$\alpha$ in mast cells and has anti-allergic activity not via inhibition of CD4+ T cell, but via inhibition of B cells. These results suggest some evidence that SGGHSS can be applied to allergic disease.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.150-157
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• 2009

This research was performed in order to investigate the anti-inflammatory effects of Bupleuri Radix(BR) on the Immune response in vitro. Cellular proliferation and cytokine production were measured in mast cells or mouse B cells or CD4 Th cells. BR water extract inhibited the secretions of TNF-$\alpha$ and IL-6 in PMA/A23187 stimulated HMC-1 cells. It increased proliferation but did not affect the expressions of CD69 or CD23 in rIL-4/anti-CD40 activated S cells. BR reduced surface IgE expression and secreted IgE but increased the production of IL-4, IFN-$\gamma$ and IgG1 in the same cells. BR caused an increase in proliferation in anti-CD3/anti-CD28 stimulated CD4 Th cells but it did not affect the differentiation of Th1 or Th2 cells. However, IL-2 was increased in BR treated Th2 cells. Considering the above-mentioned results, BR can be applied to a broad range of anti-inflammatory reactions, but our data suggest that it will not be likely to exert any effects on type 1 allergic response.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.6-10
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• 2016

Until a recent day, degradation of PEMFC (Proton Exchange Membrane Fuel Cells) has been mainly studied in unit cell. But operation and degradation of real PEMFC going along in stack instead of unit cell. Therefore in this work, ADT (Accelerated Degradation Test) of PEMFC was done in stack and the result from stack's test was compared with that of unit cell. The polymer electrolyte membrane was degraded by repeated electrochemical and mechanical degradation method among several ADT methods. Current densities of MEA at 0.6V decreased in stack and unit cell, 28.4% and 27.8% respectively after ADT for 312 hours. Hydrogen crossover current densities of membrane increased in stack and unit cell, 16.8% and 15.2% respectively after ADT for 312 hours. The result of ADT in stack was similar that of ADT in unit cell, which showed that ADT method of unit cell was available to the stack.