• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.5
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• pp.450-456
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• 2005

In this paper, the effect of adhesion properties of semiconductive-insulating interface layer of silicone rubber on electrical properties was investigated. The modifications produced on the silicone surface by oxygen plasma were accessed using ATR-FTIR, contact angle and Surface Roughness Tester. Adhesion was obtained from T-peel tests of semiconductive layer haying different treatment durations. In addition, ac breakdown test was carried out for elucidating the change of electrical property with duration of plasma treatment. From the results, the treatment in the oxygen plasma produced a noticeable increase in surface energy, which can be mainly ascribed to the creation of O-H and C=O. It is observed that adhesion performance was determined by surface energy and roughness level of silicone surface. It is found that at dielectric strength was increased with improving the adhesion between the semiconductive and insulating interface.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1868-1869
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• 2005

이 논문은 반도전 실리콘 고무 표면에 코로나 방전 처리하여 이종의 실리콘 고무와의 접착 특성을 나타낸 것이다. 반도전 실리콘 고무 표면 상태를 발수성 등급에 따른 분류와 FTIR(Fourier Transform Infrared Spectroscopy)를 사용하여 평가하였다. 표면 상태 변화에 따른 반도전 실리콘 고무의 접착 특성은 T-peel test로 접착강도를 시험하였다. 실험 결과 고에너지의 코로나 방전으로 반도전 실리콘 고무의 결합쇄가 절단되었고 이 부분에 산소가 결합되어 극성 관능기를 생성하여 표면을 산화시켰다. 이러한 표면 상태 변화에 따른 접착강도는 초기 상태일 때 보다 코로나 방전 처리 후 증가하는 것을 확인 할 수 있었다. 이 논문을 통하여 코로나 방전 처리는 이종 계면의 접착 특성을 향상시킬 수 있으며, 이종 계면에서 발생하는 절연 파괴 전압을 높여 전기절연 성능을 향상시키는데 도움이 될 것이다.

• Journal of the Korean institute of surface engineering
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• v.29 no.3
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• pp.157-162
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• 1996

The effects of microstructural change on the adhesion strength between Cu/Cr film and polyimide have been studied. Cr films (50 nm thick) and Cu films (500 or 1000 nm thick) were deposited on polyimide by DC magnetron sputtering. During Cu deposition the Ar pressure was 5 or 100 mtorr. The microstructure was observed by SEM and the adhesion was measured by T-peel test. Plastic deformation of peeled metal strips was characterized quantitatively by using XRD technique. The film in which Cu is deposited at 100 mtorr has higher adhesion strength than the film in which Cu is deposited at 5 mtorr. And in the film with same deposition pressure of 100 mtorr, the adhesion strength is increased as the deposited thickness increases from 500 to 1000 nm. The adhesion change of Cu/Cr can be interpreted as the difference in plastic deformation.

• The korean journal of orthodontics
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• v.33 no.6 s.101
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• pp.437-451
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• 2003

The purpose of this study was to measure maximum bite force and to investigate its relationship with anteroposterior, vertical, and transverse facial skeletal measurements. From among the dental students at the College of Dentistry, forty subjects (26 male and 14 female) were selected. With two sets of strain gauge, maximum bite force at the right and left first molars and anterior teeth was measured in the morning and afternoon. After taking lateral and posteroanterior cephalograms, fifty and nineteen variables were evaluated, respectively Paired t-tests and an independent t-test were done and correlation coefficients were obtained. 1. The maximum bite force at the first molars was $68.0\pm13.9kg$. in males and $55.6\pm10.5kg$ in females (p<0.05) while the force at the anterior teeth was $8.4\pm4.9kg\;and\;1.1\pm3.4kg$ respectively (p<0.05). 2. Some tendency for a greater value of maximum bite force at the preferred side was observed but not statistically significant (p>0.05). 3. Significant difference was observed between the strong bite force group and the weak bite force group in some cephalometric and other measurements (p<0.05). N-S-Ar, S-Ar-Go, FH-Hl, IMPA and MMO showed a significant difference in posterior maximum bite force (P). N-S-Ar and FH-H1 also showed a significant difference in anterior maximum bite force (A). 4. Several cephalometric variables showed some correlation with maximum bite force (p<0.05). N-S-Ar, S-Ar-Go, UGA, FH-H6, FH-H1, body weight and MMO were significantly correlated with posterior maximum bite force (P). Go-Me, P-1 and IMPA were significantly correlated with anterior maximum bite force (A).

• Journal of the Korean Society for Heat Treatment
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• v.20 no.4
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• pp.195-202
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• 2007

Corrosion resistance and torque of M10 bolt coated with Magni 565 were investigated. Corrosion protection mechanism were also studied with the microstructure of coating film. The bolts with the optimum conditions showed around $10{\mu}m$ layer thickness, a great corrosion resistance in salt spray test and a proper torque in torque/tension test. But torque coefficient k increased with the number of bolting and clamping force of M10 bolt showed significantly lower than that of specified value 28.3kN. It was thought that the repeated bolting made the coating film peel off and powdery. The sample coated with optimum coating conditions showed more higher polarization resistance and corrosion potential than the specimens of top and base coat only. The base coating film was composed of lamellar zinc flakes, which provides a large sacrificial cathodic protection. Meanwhile, the top coating film was composed of organic aluminium pigments layer, which provides barrier protection to the corrosion circumstances.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.78-81
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• 2004

In this paper, the effect of adhesion properties of semiconductive-insulating interface layer of silicone rubber on electrical properties was investigated. Surface structure and adhesion of semiconductive silicon rubber by surface asperity was obtained from SEM and T-peel test. In addition, ac breakdown test was carried out for elucidating the change of electrical property by roughness treatment. From the results, Adhesive strength of semiconductive-insulation interface was increased with surface asperity. Dielectric breakdown strength by surface asperity decreased than initial Specimen, but increased from Sand Paper #1200. According to the adhesional strength data unevenness and void formed on the silicone rubber interface expand the surface area and result in improvement of adhesion. Before treatment Sand Paper #1200, dielectric breakdown strength was decreased by unevenness and void which are causing to have electric field mitigation small. After the treatment, the effect of adhesion increased dielectric breakdown strength. It is found that ac dielectric breakdown strength was increased with improving the adhesion between the semiconductive and insulating interface.

• The Korean Journal of Food And Nutrition
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• v.24 no.3
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• pp.442-450
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• 2011

Numerous studies have suggested that dietary flavonoids contribute to prevent cardiovascular disease. Onion contains many functional phytochemicals such as quercetin. The aim of this study was to examine whether onion peel extracts supplementation affect blood lipid profiles and blood coagulation in animal model. Total 48 Sprague-Dawley male rats at 5 weeks old were divided into 6 groups with different diets(C: control, HF: high fat diet, HFOE 0.01%: high fat+onion peel extract 0.01% diet, HFOE 0.02%, HFOE 0.05%, HFOE 0.1%) for 8 weeks. Onion peel extract supplementation significantly decreased serum levels of LDL-cholesterol and increased HDL-cholesterol, while total cholesterol and triglyceride levels were not affected. Hematological parameters(hematocrit, white blood cell, red blood cell, and platelet count) and blood coagulation parameters(prothrombin time, activated partial thromboplastin time, thrombin time, and fibrinogen) were not significantly different among 6 groups. However, activated partial thromboplastin time of HFOE 0.05% group was significantly longer than that of HF group. These results indicate that onion peel extract supplementation displays hypocholestrolemic effects but does not seem to have anti-coagulation effects in high fat fed SD rats.

• Journal of Life Science
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• v.18 no.1
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• pp.46-51
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• 2008

This study investigated the effects of Punica granatum L. (PG) ethanol extracts on serum lipid levels in ovariectomized rats. In order to elucidate the effects of PG ethanol extracts on the change of lipid concentration in rats, Sprague-Dawley female rats were randomly assigned to groups as follows: sham-operated rats (sham), ovariectomized control rats (OVX-control), ovariectomized rats supplemented with ethanol extracts of PG seed at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG seed at 200 mg/kg bw/day (OVX-PS200), ovariectomized rats supplemented with ethanol extracts of PG peel at 50 mg/kg bw/day (OVX-PS50), ovariectomized rats supplemented with ethanol extracts of PG peel at 200 mg/kg bw/day (OVX-PP200). PG ethanol extracts were orally supplemented at the level of 1mL per day for 7 weeks. The body weight gain, food intake and food efficiency ratio were not significantly different between groups by t-test. The levels of total-cholesterol and triglyceride in serum were not changed by supplementation of PG ethanol extracts. The level of HDL-cholesterol on serum of the OVX-PS50 and OVX-PS200 groups were similar to the OVX-control group, but the OVX-PP50 and OVX-PP200 groups were higher than sham group. These results suggest that ethanol extracts of PG peel were more effected than those of PG seed.

• Food Science and Preservation
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• v.23 no.7
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• pp.1026-1032
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• 2016

Citrus platymamma hort. ex Tanaka is widely used in traditional Korean medicine because of its medicinal benefits including an anti-inflammatory effect. This study aimed to evaluate changes in the flavonoid content and anti-inflammatory activities of C. platymamma during its harvest period. Fruit peel samples were obtained between September 2015 and February 2016. The results indicate that C. platymamma peel extract (CPE) was an effective inhibitor of lipopolysaccharide (LPS)-induced NO production in RAW264.7 cells. The inhibitory effects of CPE at $100{\mu}g/mL$ concentration included dose-dependent decreases in the expression of iNOS and COX-2 proteins. In addition, CPE decreased the expression of pro-inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. The highest anti-inflammatory activity and flavonoid content were observed in CPE of C. platymamma peel harvested during the immature fruit period in September. Further, to assess the suitability of CPE for cosmetic use, we performed MTT assays using HaCaT keratinocytes and observed that CPE did not exhibit any cytotoxicity. To test the potential application of CPE as a cosmetic material, we also performed primary skin irritation tests on normal skin of 30 volunteers and no adverse reactions were observed. The results of this study indicate that CPE may be considered as an anti-inflammatory candidate for inclusion in cosmetic materials.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.2
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• pp.7-15
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• 2008

In this paper, the Chip-On-Flex (COF) assembly process using anisotropic conductive films (ACFs) was investigated and the reliability of COF assemblies using ACFs was evaluated. Thermo-mechanical properties of ACFs such as coefficient of thermal expansion (CTE), storage modulus (E'), and glass transition temperature $(T_g)$ were measured to investigate the effects of ACF material properties on the reliability of COF assemblies using ACFs. In addition, the bonding conditions for COF assemblies using ACFs such as time, temperature, and pressure were optimized. After the COF assemblies using ACFs were fabricated with optimized bonding conditions, reliability tests were then carried out. According to the reliability test results, COF assemblies using the ACF which had lower CTE and higher $T_g$ showed better thermal cycling reliability. Consequently, thermo-mechanical properties of ACFs, especially $T_g$, should be improved for high thermal cycling reliability of COF assemblies using ACFs for compact camera module (CCM) applications.