• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.377-380
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• 1997

In order to investigate the electrical characteristics due to the curing condition of silicone gel for Power Semiconductor, the V-I characteristics is studied. For experiment, We have made up several samples of different curing temperature and time such as 1[H],2[H] at 150[$^{\circ}C$], 160[$^{\circ}C$], 170[$^{\circ}C$]. As a result of the V-I characteristics, it is confirmed that the properties of specimen cured at 170[$^{\circ}C$], 2[H] is stable.

• 대한기계학회논문집A
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• 제34권10호
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• pp.1499-1505
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• 2010

유연성 공구를 가진 자기연마는 고경도 소재 및 자유곡면 형상 표면의 나노메터급 가공이 가능한 강점을 지닌다. 이러한 자기연마에서 자기연마입자는 시간적, 비용적 측면에서 단순 혼합형 입자가 유리하다. 그러나 단순혼합형 입자는 가공 중 공구로부터 쉽게 이탈하게 되어 가공 시간이 증가 할수록 매우 낮은 가공 효율을 가진다. 따라서 본 연구에서는 단순 혼합형 입자에 오일을 대신하여 실리콘 겔을 매개물로 사용하는 자기연마 입자를 연구하고 그 특성을 분석하였다. 그 결과 자기력 향상과 별개로 입자간 응집력을 높여 입자의 이탈을 줄여 표면거칠기의 향상에 효과가 높음을 확인 하였다. 그리고 실험계획법을 이용하여 고경도 소재인 텅스텐 카바이드의 실리콘 겔 자기연마에서 각 공정변수가 표면거칠기의 향상에 미치는 특성을 평가하고 이를 최적화 하였다.

• Archives of Plastic Surgery
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• 제50권2호
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• pp.160-165
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• 2023

Background The number of cosmetic and reconstructive surgeries that use breast implants is increasing in Korea. Recently, it has been reported that breast implant-associated anaplastic large-cell lymphoma is related to textured breast implants, and interest in classification according to the texture of breast implants is increasing. However, there is currently no clear and unified classification. In particular, the definition of "microtextured" is highly varied. In this study, we retrospectively investigated and analyzed the clinical outcomes of smooth and microtextured breast implants. Methods A retrospective chart review of all patients who underwent breast augmentation surgery with smooth and microtextured silicone gel implants between January 2016 and July 2020 was performed. We retrospectively analyzed implant manufacturer, age, body mass index (BMI), smoking status, incision location, implant size, follow-up period, complications, and reoperation rate. Results A total of 266 patients underwent breast augmentation surgery, of which 181 used smooth silicone gel implants and 85 used microtextured silicone gel implants. Age, BMI, smoking status, implant size, and follow-up period were not significantly different between the two groups. Similarly, complications and reoperation rates were not significantly different between the two groups. Conclusion It is important to provide information regarding the clinical risks and benefits of breast implants to surgeons and patients through a clear and unified classification according to the texture of the breast implant.

• 대한치과보철학회지
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• 제37권2호
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• pp.200-211
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• 1999

For many years permanent soft denture liners has been widely used in dental practice directly or indirectly because of its function in absorbing and distributing the impact force. However, it reveals problems such as lack of permanency and decreased bond strength in long term use. The purpose of this study is to measure the bond strength and failure between denture base resin and several permanent liners. Lucitone 199 was used as denture base resin with soft acrylic liners (Triad, Tokuso Rebase) and silicone elastomers (Tokuyama, Ufi Gel C) bonded to measure the tensile strength before and after thermocycling. The thermocycling was done in 2000 cycles at $5^{\circ}C,\;26^{\circ}C\;and\;55^{\circ}C$ and the measured tensile strength values before and after thermocycling were compared. The mode of failure was investigated in the separated specimens. The results are as follows. 1. As to tensile strength, the strongest material is Tokuso Rebase followed by Triad, Tokuyama, Ufi Gel C in before thermocycling and the order of Triad, Tokuso Rebase, Tokuyama, Ufi Gel C in after thermocycling state. There was significant difference between the values of Triad, Tokuso Rebase and Tokuyama, Ufi Gel C(p<0.05). 2. As to degree of displacement, Ufi Gel C showed most displacement with or without thermo-cycling treatment and also the difference was significant with the other materials(p<0.05). 3. As to comparisons before and after thermocycling, Tokuso Rebase and Tokuyama showed significant difference in bond strength, whereas Triad and Tokuso Rebase showed significant difference in the degree of displacement(p<0.05). 4. In debonded specimens, Triad and Ufi Gel C showed adhesion failure and Tokuyama showed cohesion failure. Both failures were observed in Tokuso Rebase with adhesion failure up to 70%. The results of this study showed that degree of bond strength between permanent soft denture liner and denture base resin were variable. There was a significant difference between soft acrylics and silicone elastomers with regard to bond strength. Further research in improving bond strength of widely used silicone elastomers and in developing the method of measuring bond strength between denture base resin and the lining materials is needed.

• 한국전기전자재료학회논문지
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• 제17권10호
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• pp.1068-1078
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• 2004

In this paper we investigated the characteristics of surface degradation in silicone rubber due to corona exposure and recovery mechanism. It was shown that surface free energy was 22.42 mJ/$m^2$ on initial sample but surface free energy was approximately increased to 71.14 mJ/$m^2$ after 45 minutes. However, surface free energy on silicone rubber after corona discharge treatment was completely recovered within a short time due to diffusion of low molecular weight(LMW) silicone fluid. It was shown that corona discharge insured the increase of diffusible LMW chains, which could lead to recover the surface hydrophobicity. 200～370 g/mol distribution of LMW silicone fluid which was extracted by solvent-extraction with gel permeation chromatography (GPC) was contributed to recovery. The surface degradation characteristics on silicone rubbers and the recovery mechanism based on our results were discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.503-506
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• 2004

In this paper we investigated the changes of surface hydrophobic characteristics on silicone rubbers by corona discharge treatment and also investigated the distribution and the behavior of low molecular weight(LMW) silicone fluid which was extracted by solvent-extraction with gel permeation chromatography(GPC). It was shown that contact angle was $110.5^{\circ}$ on initial sample but contact angle was approximately decreased to $10^{\circ}$ after 45 minutes. However the surface hydrophobic characteristic on silicone rubbers which were removed from corona discharge was recovered within 5 hours. It was shown that corona discharge insured the increase of diffusible LMW chains, which could lead to recover the surface hydrophobicity. The surface hydrophobic characteristics on silicone rubbers and the recovery mechanism based on our results were discussed.

• 한국정밀공학회지
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• 제29권3호
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• pp.266-272
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• 2012

This paper has aims to share fundamental knowledge for magnetic abrasive polishing and to mainly introduce recent research results. In order to enhance a magnetic flux density for nonferrous materials, advanced magnetic abrasive polishing system which is called 2nd generation system was established by electro-magnet array table, and the effectiveness of the electromagnet array table was evaluated in real polishing experiments. To increase adhesiveness of the abrasives in high speed polishing, a silicone gel agent was proposed and carbon nanotube particles as new magnetic abrasives were applied in the magnetic abrasive polishing. In addition, a strategy for optimal step-over determination by heuristic algorithm was introduced for applying large size workpiece. Curved surfaces having a uniform radius were simulated and tested with installed electro-magnet array table.

• 대한화상학회지
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• 제22권2호
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• pp.30-33
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• 2019

Purpose: Wound healing and scar management of donor site after skin graft should not be overlooked. Patients continue to complain of dryness, itching sensation. Such discomfort can cause irritation to the patients and lead to delayed healing or secondary infection. Thus, the author predicted Eucalyptus Oil, which acts on Transient Receptor Potential Melastatin 8 would be effective in regulating scar by reducing itching sensation in donor site when combining conventional silicone materials. Methods: The study was performed on 30 patients who underwent split thickness skin graft with lateral thigh as donor site between January 2017 and August 2018. First, primary evaluation of fully epithelized donor site scar three weeks after surgery was conducted. Control group (n=15) applied silicone gel (Kelo-cote, USA) solely two times a day. study group (n=15) applied Eucalyptus oil, combined with silicone gel. After 3 months of follow up, donor scar was evaluated using Vancouver scar scale and VAS scores of subjective patient reports regarding pain and itching sensation. Results: It was confirmed that both groups showed stable scar improvement comparing scar quality for 3 months. After 3 months, scar quality in study group showed superiority in pigmentation, pliability and pruritus compared to control group. Conclusion: Application of Eucalyptus Oil combined with conventional silicone gel is favorable to scar management and may give additional benefit of alleviating pruritis symptoms.

• 한국컴퓨터산업학회논문지
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• 제3권12호
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• pp.1747-1758
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• 2002

실리콘 젤의 경화조건에 따른 전기적 특성을 조사하기 위하여 절연파괴특성에 대한 실험을 실시하였다. 실험을 위해 온도 100[$^{\circ}C$], 125[$^{\circ}C$], 150[$^{\circ}C$], 160[$^{\circ}C$], 170[$^{\circ}C$], 180[$^{\circ}C$]에서 각각 30[Min], 1[H], 2[H]동안 경화된 여러 시료를 제작하였다. 절연파괴실험에서 사용된 전극의 재료는 순도 99.9[%]의 구리이며, 전극간 간격은 1~3[mm]로 하였고, 전극의 두께는 0.2[mm]이다. 실험결과 온도 170[$^{\circ}C$]에서 2[H] 경화된 시료의 전기적 특성이 가장 우수하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.270-272
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• 1997

In order to a study on the electrical properties of silicone gel due to the curing condition, the volume resistivity test is researched. For experiment, we have made up several samples of different curing temperature and time such as 1[H], 2[H] at 125[$^{\circ}C$], 150[$^{\circ}C$], 160[$^{\circ}C$], 170[$^{\circ}C$], 180[$^{\circ}C$]. A measurement of volume resistivity using the VMG-1000 highmegohm meter is recorded after 10 minutes when the each voltage, and DC 500[V] and 1000[V] is applied. A coaxial cylindrical liquid electrode to measure volume resistivity of specimen is used, and its geometric capacitance is 2[pF]. As a result of the experiment, the electrical properties of specimen cured at 170[$^{\circ}C$] for 2[H] is superior.