• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.4
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• pp.147-151
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• 2002

The resistances of metal2 contact to metall and poly Si are checked by various RF etch conditions in terms of pre-cleaning. The changes of resistance are evaluated by statistical analysis method(SAS) for the AC bias power, coil power and RF target. The contact area on poly Si is shown by TEM image and the distributions of contact resistance according to ar etch target and RTP are investigated. The RTP groups have larger variations than normal RF etch targets. When the RF etch target becomes lower and coil power becomes higher, the resistances of metal2 contact to metals and poly Si have lower contact resistance. But the condition of AC bias power did not satisfied low meta12 contacts resistance for metall and poly Si simultaneously. The R-square of ststistical analysis was 0.98 for resistances of meta12 contact to poly Si and 0.87 for resistances of meta12 contact to metall.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.3
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• pp.205-212
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• 1995

Effect of Mn addition on rolling contact fatigue of C-base induction hardened bearing steels has been investigated to develop inexpensive surface-hardened bearing steels with improved resistance to rolling contact fatigue. Fatigue tests were conducted in elasto-hydrodynamic lubricating conditions at a shaft speed of 5,000rpm, under max. Hertzian stress of $492kg/mm^2$. It was found in the C-Mn steels that effective depth of induction hardened layer and amount of retained austenite were slightly increased in comparison with those of C-base steels. finer interlamellar spacing of pearlite in the C-Mn steels was also observed using TEM. Decomposition of retained austenite during rolling contact fatigue was smaller in quantity in the C-Mn steels than C-base steels. This might be associated with enhanced mechanical stability of retained austenite with addition of Mn. Statistical analysis of fatigue life for C-Mn steels using Weibull distribution indicated that improved resistance to rolling contact fatigue was mainly attributed to transformation induced plasticity and mechanical stability of retained austenite.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.159-162
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• 2009

In temperature controlled batch reactor, the effect of temperature and contact metals on the thermal stability of Exo-tricyclo[$5.2.1.0^{2,6}$]decane (tricyclodecane, exo-THDCP) were investigated by use of GC/MS. And the characteristic of metal in contact with tricyclodecane were analyzed by SEM-EDX. In fuel temperature variation test, thermal decomposition of exo-THDCP was occurred at $350^{\circ}C$. In case of fuel contact metals, Titanium was less effective to decomposition of exo-THDCP than stainless steel 304, 316.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.17-22
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• 2018

A glove valve regulates the flow in a pipeline as a kind of control valve. However, when the disc and seat contact, the valve structure can be distorted and flow can leak due to the elongation of the valve material under high pressure. The surface texture is not good enough to seal the contact surface (in practice) because the lapping process is usually done manually. Furthermore, assembly performance is analyzed by structural analysis. Compared with a standard seat, the newly designed seat had a smaller radial deformation and a larger longitudinal deformation. Therefore, the newly designed seat can maintain a tight and uniform contact with the disc with a reduced radial deformation and an expanded available seal area with an increased longitudinal deformation. The seal performance of the glove valve has been improved in a cost-effective manner.

• Journal of Korea Foundry Society
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• v.28 no.4
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• pp.184-189
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• 2008

Ag-Cd alloy has been widely used as an electrical contact material, since Ag-Cd alloy has a good wear resistance and stable contact resistance. But nowadays Ag-Cd alloy is not considered as electrical contact material any more due to detrimental effect on environments. Currently, active researches are being performed on ($Ag-SnO_2$ and $Ag-SnO_{2}-In_{2}O_{3}$) as an alternative solution which can fix the remaining environmental problems. However, $In_{2}O_{3}$ is relatively expensive and Ag-Sn alloy has low wear resistance. Our recent research results show that Ag-X%Zn-Y%Sn has similar physical and chemical properties. In the present study, so we tried to change and to optimize the Zn oxide content to over 6 wt% and Sn oxide content with 0.5, 1.0, 1.5 wt%. Results obtained from the experiments on the Ag-X%ZnO-Y%$SnO_2$ are discussed.

• The Korea Journal of Herbology
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• v.21 no.1
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• pp.9-15
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• 2006

Objectives : Lonicerae Flos has been known as a useful plant with anti-inflammatory, antioxidative and immunosuppressive activity. To evaluate anti-inflammatory effect of Lonicerae Flos, we treated Lonicerae Flos-skin in animal model system induced contact hypersensitivity. Methods : Contact hypersensitivity, a local inflammatory response of the skin, was induced by spreading the right ear of BALB/c mouse with 1% DNCB. Lonicerae Flos-skin was prepared by dissolving 1% water extract of Lonicerae Flos in skin vehicle and treated everyday for 2 weeks on the right ear. Results : Lonicerae Flos-skin significantly reduced a mouse ear thickness swelled by 1% of DNCB treatment compared with skin vehicle-treated control group. Lonicerae Flos-skin also reduced IgG and IgE in serum obtained from blood of 1% DNCB-treated mouse. Conclusion : These results showed that Lonicerae Flos-skin could be used as a pharmaceutical material with antiinflammatory effects by reducing IgG and IgE in contact hypersensitivity mouse model by DNCB.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.1-5
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• 2009

Objectives : HRHDT has been known as a useful prescription with antibiotic, anti-inflammatory, antioxidative and immunosuppressive activity. To evaluate anti-inflammatory effect of HRHDT, we treated HRHDT-skin in Balb/c mice model induced contact hypersensitivity. Methods : Contact hypersensitivity, a local inflammatory respinse of skin, was induced by spreading the back skin of Balb/c mice with 1% DNCB. HRHDT-skin was prepared by dissolving 3% 1,3-butylene glycol extract of HRHDT in solution and treated 2 weeks on the back skin. Results: HRHDT-skin significantly reduced TEWL and erythema by 0.4-1% of DNCB treatment compared with control group. HRHDT-skin reduced IgE on serum obtained from blood of DNCB-treated Balb/c mice. Histopathological examination showed that thickening of the epidermis, hyperkeratosis and the infiltration of inflammatory cells were found in Balb/c mice under conventional circumstances. Conclusions : These results showed that HRHDT-skin could be used as a pharmaceutical material with antiinflammatory effects by reducing IgE in contact hypersensitivity dermatitis Balb/c mice by DNCB.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.31 no.2
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• pp.123-132
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• 2018

Objectives : The purpose of this report is to know the effect of Korean medicine treatments on Allergic Contact Dermatitis. Methods : We treated a 63-years-old man patient with Allergic Contact Dermatitis on the left medial calf with Korean medicine. After Korean medical treatment for 26 days, we identified a reduction in size of erythema and loss of color fading, exudates and edema. We recorded pictures of changes on symptoms. Results & Conclusions : The symptoms of Allergic Contact Dermatitis were improved. Erythema, edema, exudate were lost. Thus Korean medicine treatments are effective on allergic contact dermatitis.

• Journal of Environmental Science International
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• v.3 no.4
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• pp.427-437
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• 1994

Batch experiments were performed to evaluate the effect of sludge acclimation and contact load on the behavior of phosphorus and organic substrates under anaerobic conditions. Four different sludges were acclimated in the sequencing batch reactors operated by intermittent aeration. All the experiments performed in a bench scale have shown the following results: 1. The unreleaseable phosphorus contents for four different sludges are the range of 16 mg P/g SS to 24 mg P/g SS, depending on the sludge acclimation conditions. 2. All the specific substrate uptake rates(SSUR) are expressed in the first order equation for releaseable phosphorus contents. The reaction rate coefficient k, has the values of 4.0, 8.9, and 13.8 mg COD/mg P/hr, depending on the contact load and slut식e species. 3. As reaction proceeds, the ratios of $\delta$P to -$\delta$COD at high contact load are almost constant in the range of 0.10 to 0.14, but at low contact load, they increase from 0.08 to 0.27.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.114-117
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• 2004

The purpose of this study is to investigate geometric effect on the contact stress at a lip seal. The geometries of interest were angle, thickness of lip seal and width of contact surface. The contact stress was calculated by using a coupled thermo-mechanical analysis method. The friction thermal load between lip seal and sleeve was adopted to design load. Based on the FEA results, design variables for controlling the maximum contact stress at the lip seal were identified.