• Korean Chemical Engineering Research
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• 제55권1호
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• pp.34-39
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• 2017

본 실험은 방사선을 이용하여 유착방지용 Carboxymethyl cellulose sodium salt (CMC)/Porcine Cartilage Acellular Matrix (PCAM) 수화젤 필름에 대해 연구하였다. 방사선 조사시 CMC/PCAM의 농도 및 혼합비율에 따른 필름의 형태학적 구조, 젤화율, 젤강도, 팽윤도 등을 분석하였다. 방사선에 의해 가교된 CMC/PCAM 필름은 CMC 필름보다 물리적인 특성인 젤화율이 낮게 측정되었다. 또한, 가교된 CMC 필름보다는 CMC/PCAM 필름에서 인간 혈관내피세포의 부착 및 증식율이 감소하였다. 우리는 PCAM에 함유한 세포의 항부착 성분이 도입된 CMC/PCAM 필름과 CMC 필름은 세포의 접착 및 증식율을 낮추는 것을 확인하였다. 결론적으로, 본 연구에서는 방사선 가교된 CMC/PCAM 수화젤 필름은 유착방지 향상을 위한 유착방지제로서 응용이 기대된다.

• Restorative Dentistry and Endodontics
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• 제35권1호
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• pp.5-12
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• 2010

본 연구에서는 인위적으로 노출시킨 비글견의 치수조직을 기존의 수산화칼슘제재와 MTA, 접착성 레진, 광중합형 수산화칼슘제재를 사용하여 직접치수복조한 후 각 재료에 따른 치수의 반응을 광학현미경 하에서 조직학적으로 관찰하여 비교분석하였다. 2마리 비글견의 36개 치아를 이용하여, 실험적으로 치수를 노출시키고 노출된 치수에 치수복조재를 적용한 후 와동은 복합레진으로 충전하여 직접치수복조술을 시행하였다: (1) Mineral Trioxide Aggregate (MTA: $ProRoot^{(R)}$ MTA, Dentsply, Tulsa, USA), (2) Clearfil SE Bond (Dentin adhesive system: Kuraray, Osaka, Japan), (3) Ultra-Blend (Photopolymerized Calcium hydroxide: Ultradent, South Jordan, USA), (4) Dycal (Quick setting Calcium hydroxide: LD Caulk Co., Milford, USA). 희생전 90일, 30일, 7일 전에 각 복조재별로 3개씩의 와동을 충전하였고 비글견을 희생시키고 조직시편을 제작하였다. 시편을 H&E 염색 후 광학 현미경으로 치수염증반응과 경조직 형성 정도를 관찰하였다. MTA 군은 초기에는 경조직 형성이 관찰되지 않고 치수조직의 위축과 부분괴사가 관찰되었으나 시간이 지나면서 경조직 형성이 관찰되었다. Clearfil SE Bond군은 초기에 염증세포의 침윤과 치수세포의 괴사를 관찰할 수 있었고 시간이 지날수록 치수 세포의 괴사가 더욱 진행한 양상을 보였다. Ultra-blend 군과 Dycal 군은 MTA 군과 비슷하게 초기에는 경조직 형성을 보이지 않고 중등도의 염증반응이 관찰되었으며 시간이 지나면서 경조직 형성이 관찰되었다. MTA, 수산화칼슘제재와 광중합 수산화칼슘제재는 초기의 치수염증반응 이후 조상아세포층, 상아질교 형성을 보여 직접치수복조재로 적당하였으며, 접착성 레진은 심한 염증반응과 치수 조직의 괴사 양상을 보여 직접치수복조재로 부적당하다는 결론을 얻을 수 있었다.

• 한국멀티미디어학회논문지
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• 제12권7호
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• pp.971-978
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• 2009

본 연구는 위상제어형 루프안테나에 관한 것으로서, 유전체기판 상에 에칭기법이나 프린트기법으로 루프안테나용 동박패턴을 제작함에 있어, 루프에서 발생하는 전자계가 서로 보완위상이 되게 배치하여, 인접하는 루프패턴 간에서 방사되는 전자계가 서로 충돌하지 않게 방사되는 위상제어형 루프코일 배치에 관한 것이다. 이 방법으로 인접하는 각 루프코일이 서로 보완위상으로 배치되어 전자계가 원만하게 방사되어, 방사 손실이 없고 방사 효율이 뛰어나게 된다. 또한 복수 개의 각 루프코일의 길이를 서로 달리함으로 인해, 각 루프코일의 길이가 달라짐에 따라 공진주파수가 달라지고, 이러한 공진점이 다른 루프코일을 밀결합 시킴으로 인해 공진주파수 대역을 넓게 할 수 있고, 원하는 대역만큼 조절할 수가 있게 된다. 이로 인하여 크기 20mm$\times$20mm 이하의 사이즈에, 두께 0.4mm 이하의 박막의 유전체기판에 CDMA850 휴대폰대역 및 PCS, WCDMA 등의 안테나를 구현하여 게인 0dBi 이상 방사효율 60% 이상의 안테나를 구현할 수가 있다.

• Current Photovoltaic Research
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• 제4권2호
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• pp.59-63
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• 2016

A key point of a soldering process for photovoltaic (PV) modules is to increase an adhesive strength leading a low resistivity between ribbon and cell. In this study, we intended to optimize a heating condition for the soldering process and characterize the soldered joint via physical and chemical analysis methods. For the purpose, the heating conditions were adjusted by IR lamp power, heating time and hot plate temperature for preheating a cell. Since then the peel test for the ribbon and cell was conducted, consequently the peel strength data shows that there is some optimum soldering condition. In here, we observed that the peel strength was modified by increasing the heating condition. Such a soldering property is affected by a various factors of which the soldered joint, flux and bus bar of the cell are changed on the heating condition. Therefore, we tried to reveal causes determining the soldering property through analyzing the soldered interface.

• 구강회복응용과학지
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• 제23권4호
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• pp.303-312
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• 2007

Recently several studies have been developed not only to apply bone materials to bony defect, but also to use osteogenic and osteoinductive materials to form bone more effectively. In 1998 Mark et al applied gel formation of PRP(platelet-rich plasma) in bony transplantation for mandibular reconstruction as one of the method of stimulating bone formation in maxillofacial area, which is contain of varies growth factors. After he reported that PRP accelerate bone formation, which is used in varies bone transplantation and augmentation with a good result. Especially there are amount of growth factors in PRP, and PRP increase angiogenesis, cell division, and mesenchymal cell growth. Moreover it is capable of osteoconduction, hemostatitis, anti-infection, forming the shape at transplantation, ease of handling, and recipient site stability. So it is known that success rate is high in bone transplantation. However PRP need tissue adhesive to make plasma to solid form. Thrombin and calcium chloride, component of PRP, is extracted from autogenic donor. So it is expensive to extract and there is possibility of hepatitis, AIDS, and hematogenous metastasis. After all, tissue adhesive have the limitation and danger of use. So we are willing to introduce that we had get some idea after using PRF(platelet-rich fibrin) in the various hard and soft tissue bony defect, which is self extracted simply and contain growth factors.

• 대한한방종양학회지
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• 제4권1호
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• pp.17-36
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• 1998

This experimental study was carried out to evaluate the effects of Hwallakhyoreungdan on angiogenic inhibition mechanism. In order to investigate the effects of Hwallakhyoreungdan on angiogenic inhibition mechanism, MTT assay, cell adhesive inhibition effect, DNA fragmantaion analysis, Nuclear condensation assay, FACScan analysis, Angiogenic lumen formation assay, Immunocytochemistry analysis, RT-PCR for mRNA expression, Western blot analysis and Confocal analysis for $Ca^{2+}$ change were performed. The results were summarized as follows: 1. The cell adhesive inhibition ability was strong from $5{\mu}g/ml$. 2. The $G_0/G_1$ arrest peak was existed on ECV304 cell-line. 3. The cells on Collagen plate were inhibition of proliferation and inducement of apoptosis by HR water extract. 4. Angiogenic lumen formation was inhibited by HR water extract. 5. LFA-1 and ELAM-1's expression were inhibited by HR water extract. They are commenly participation on inflammation and tumor regeneration. 6. The expression of MMP-9 and uPA were inhibited by HR water extract. 7. The expression of integrin ${\alpha}_v{\beta}_3$ was inhibited by HR water extract. 8. The expression of intracellular molecule were successively inhibited by HR water extract therefore the proliferation of ECV304 cell line was stopped and apoptosis was induced. 9. The change of $Ca^{2+}$ was decreased by HR water extract it cause confusion of signal transduction pathway therefore it was take part in apoptosis. According to the results, Hwallakhyoreungdan showed to be a key antaonist of integrin ${\alpha}_v{\beta}_3$, and to be induction of apoptosis by p53 through flow cytometry. This report also demonstrated that expressions of MMP-9 and uPA was blocked under the angiogenesis model. Thus, we suggests that Hwallakhyoreungdan blocks angiogenesis by inducing apoptosis of ECV304 and ECVPAR cell lines and another oriental herbal medicine that treats blood-stasis type also has angiogenic inhibition effects.

• 전기학회논문지P
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• 제65권4호
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• pp.250-254
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• 2016

In this paper, solar-cell modules were fabricated by low-temperature bonding method of construction using CF. CF adhesive strength of cells at 180 degree using 3bus bar structure was measured average 2.4N. As the bonding temperature got higher, Voc and Iscwas increased. And at $185^{\circ}C$, Rseries was measured 0.013[${\Omega}$] which is the highest point. At $185^{\circ}C$, 2N and 6sec in bonding time, $P_{max}$ was measured 3.954[W], fillfactor was measured 67.36[%] and efficiency was measured13.178[%] the highest point.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.129-132
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• 2007

Advanced structure of metal-supported solid oxide fuel cells was devised to overcome sealing problem and mechanical instability in ceramic-supported solid oxide fuel cells. STS430 whose dimensions were 26mm diameter, 1mm thickness and 0.4mm channel width was used as metal support. Thin ceramic layer composed of anode(Ni/YSZ) and electrolyte(YSZ) was joined with STS430 metal support by using a cermet adhesive. $La_{0.8}Sr_{0.2}Co_{0.4}Mn_{0.6}O_{3}$ perovskite oxide was used as cathode material. It was noted that oxygen reduction reaction of cathode governed the overall cell performance from oxygen partial pressure dependance.

• Transactions on Electrical and Electronic Materials
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• 제16권1호
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• pp.20-24
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• 2015

We studied the relationship between the surface smoothness of the internal Cu ribbon and the morphology of the Sn-Pb plating layer for solar cell modules. A bumpy surface was observed on the surface of the solar ribbon, which caused irregular reflection of light. Large, Pb-rich, primary ${\alpha}$-phases were found below the convex surface of the solar ribbon, passing from the surface of the internal Cu ribbon to the surface of the plating layer. The primary ${\alpha}$-phases heterogeneously nucleated on the convex surface of the Cu ribbon, and then largely grew to the convex surface of the plating layer. The restriction of the primary ${\alpha}$-phase's formation was enabled by enhancing the smoothness of the Cu ribbon's surface; it was also possible to increase the adhesive strength and decrease contact resistance. We confirmed that the solar ribbon's surface smoothness depends on the internal Cu ribbon's surface smoothness.

• 한국컴퓨터정보학회논문지
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• 제22권10호
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• pp.1-7
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• 2017

In this paper, the separation force measuring system is developed. The separation force aries due to adhesive strength between semiconductor epoxy molding compound(EMC) and the metal plate in semiconductor formed plate. In general, when removing the metal plate in semiconductor formed plate from semiconductor epoxy molding compound, excessive strength can result in a increase in semiconductor defect rates, or conversely, if too little force is exerted on the metal plate in semiconductor formed plate, the semiconductor production rates can decrease. In this study, the design criteria for the selection of the AC servo motor, the role of the ball screw, the relationship between the load cell and the ball screw, and the rate of deceleration are given. In addition, minimizing the reject rate of semiconductors and maximizing the semiconductor production rate are achieved through the standardization of the collected separation force data measured by the proposed system.