• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.40-44
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• 2011

Recent studies in crystalline silicon solar cell fabrication have been focused on high efficiency and low cost. However, the rising of the cost results in additional processes to approach high efficiency. The fabrication process also becomes complicated with additional technologies. In this paper, we studied the selective emitter formation with phosphorous paste to improve the conversion efficiency. Selective emitter formations like two-step diffusion or etch-back method require at least one more step compared in the conventional line since heavily and lightly doped area was needed to form separately.However,one-step diffusion process is the method diffusing heavily and lightly doped area at the same time only with additional screen-printing step. This study lays the foundation for the simple way to form the selective emitter.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.383-387
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• 2009

Multi-crystalline silicon surface etching without grain-boundary delineation is a challenging task for the fabrication of high efficiency solar cell. The use of sodium hydroxide - sodium hypochlorite (NaOH40% + NaOCl 12%) solution for texturing multi-crystalline silicon wafer surface in solar cell fabrication line is reported in this article. in light current-voltage results, the cells etched in NaOH 40% + NaOCl 12% = 1:2 exhibited higher short circuit current and open circuit voltage than those of the cells etched in NaOH 40% + NaOCl 12% = 1:1 solution. we have obtained 15.19% conversion efficiency in large area(156cm2) multi-Si solar cells etched in NaOH 40% + NaOCl 12% = 1:1 solution.

• 한국수소및신에너지학회논문집
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• 제13권2호
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• pp.159-167
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• 2002

The operation results of the 2kW class plate type reformer, which has several advantages compared with the tubular burner type reformer, are analyzed. This plate type reformer is composed of six combustion chambers and five reforming chambers by turns. The methane conversion rate at 1.6 absolute pressure is about 84%, which is reasonably similar to theoretical value, 85.3%. Though the abrupt interruption was made just by the carbon deposition during heating the fuel line to combustion chambers around 200 hours operation, the overall steady state operation is more than 450 hours. These operation results show the verification of long run performance and the possibility of direct connection between plate reformer and fuel cell stack.

• 약학회지
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• 제47권1호
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• pp.37-45
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• 2003

The present study was undertaken to investigate the anticancer activity of monoterepenes in the animal and the cancer cell line tests. Both of the noncyclic and cyclic monoterpenes showed significant life prolonging effects on ICR mouse with abdominal cancer induced by Sarcoma 180 cells up to 67.4％ and 63.5％ in case of linalool and geraniol, respectively. Linalool and geraniol also exhibited very excellent cytotoxicity against L1210 leukemic cells with $IC_{50}$/ value of 0.32 $\mu\textrm{g}$/mι in 5 days culture condition. In the presence of linalool and geraniol, the generation of $O_2$$^{[-10]}$ ion were found to be increased proportionally to the cytotoxicity arisen from these monoterpenes. Furthermore, the antioxidant enzymes activities such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) responsible for the conversion of $O_2$$^{[-10]}$ ion to $H_2O$$_2$ and then to $H_2O$ augmented remarkably by linalool and geraniol. All data put together it can be postulated that monoterpenes may kill abdominal cancer cells of ICR mouse probably by activating anticancer system of the body, whereas the death of L1210 cells may be due to the detrimental attacks of reactive oxygen species (ROS) including $O_2$$^{[-10]}$ in spite of antioxidant enzymes activities to overcome the ROS attacks.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.159.1-159.1
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• 2011

Partial oxidation reformer was fabricated and operated using commercial transportation fuels. Fuel injector and heating coil were used for fuel atomization and startup, respectively. The reformer was designed to produce syngas for $150{\sim}200W_e$ class solid oxide fuel cell. The reformer was operated in the $O_2$/C range between 0.6 and 0.8 while the capacity was fixed at $150W_e$. The temperature range in catalyst bed was between $500^{\circ}C$ and $900^{\circ}C$. Only 83% fuel was converted to $H_2$, CO, $CO_2$ and $CH_4$ at the operating conditions. The lowest temperature increase to $700^{\circ}C$ when the reformer was operated at $200W_e$, Although the temperature profiles was improved, fuel conversion was 88%. On the other hand, fuel was completely converted when micro-reactor operated at the same condition. This difference maybe due to aromatic compounds formation at homogeneous region. In addition, a significant amount of coke deposition was observed at vent line. Homogeneous reaction depends on the degree of mixing. For this purpose, two fluid nozzle and Ultra sonic injector were compared to investigate the effect of atomization. Sauter mean diameter(SMD) of Ultra sonic injector was lower than two-fluid nozzle at test condition. However, conversion efficiency and fuel conversion were not improved by using two-fluid nozzle. these results imply that the temperature of homogeneous reaction region should be controlled to prevent coke formation.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권12호
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• pp.565-569
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• 2006

Plasma enhanced chemical vapor deposition(PECVD) is a well established technique for the deposition of hydrogenated film of silicon nitride (SiNx:H), which is commonly used as an antireflection coating as well as passivating layer in crystalline silicon solar cell. PECVD-SiNx:H films were investigated by varying the deposition and annealing conditions to optimize for the application in silicon solar cells. By varying the gas ratio (ammonia to silane), the silicon nitride films of refractive indices 1.85 - 2.45 were obtained. The film deposited at $450^{\circ}C$ showed the best carrier lifetime through the film deposition rate was not encouraging. The film deposited with the gas ratio of 0.57 showed the best carrier lifetime after annealing at a temperature of $800^{\circ}C$. The single crystalline silicon solar cells fabricated in conventional industrial production line applying the optimized film deposition and annealing conditions on large area substrate of size $125mm{\times}125mm$ (pseudo square) was found to have the conversion efficiencies as high as 17.05 %. Low cost and high efficiency silicon solar cells fabrication sequence has also been explained in this paper.

• 한국전자파학회논문지
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• 제19권9호
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• pp.985-991
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• 2008

본 논문은 차동과 공통 모드로 동작하는 메타 재질 구조를 바탕으로 평형 믹서 수신기를 제안한 것이다. 이 메타 재질 구조는 리키 웨이브 안테나로 동작하며, 순수 공통 모드는 억압한다. 이러한 특성은 낮은 LO 누설전력과 높은 RF-LO 고립도를 갖고 있어 LO과 RF 경로에 추가적인 여파기가 필요로 하지 않는다. 이 메타 재질은 차동 모드 동작에서는 Composite Right/Left-Handed(CRLH) 메타 재질처럼 동작하고, 공통 모드에서는 차단되는 성질을 갖는 단위 셀을 기초로 설계하였다. 제안된 메타 재질의 차동과 공통 모드 특성은 실험 결과를 통하여 증명하였다. 메타 재질을 이용한 수신기는 $1.96{\sim}2.40$ GHz의 주파수 범위에서 동작하는 안테나와 평형 믹서를 집적화시켜 제작하였고, 2.4 GHz에서 21.1 dB의 믹서의 변환 손실을 얻었다.

• 대한한의학회지
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• 제26권1호
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• pp.37-45
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• 2005

In the present study, we examined the effect of crude methanolic extract (CME) from Euonymus alatus (Thunb.) Sieb on arachidonic acid (AA) cascade in SKBR3 human breast cancer cell line. CME had a potent inhibitory activity of prostaglandin E2 (PGE2) release induced by A23187, a $Ca^{2+}$ ionophore. The inhibition was concentration-dependent, with the 50 value of about 5 M. CME had no inhibitory effect on A23187-induced phosphorylation of p42/p44 extracellular signal regulated kinase/mitogen-activated protein kinase or on the liberation of [14C]-AA from the cells labeled with [14C]-AA. However, CME concentration-dependently inhibited the conversion of AA to $PGE_2$ in microsomal preparations, showing its possible inhibition of cyclooxygenase (COX). In enzyme assay in vitro, CME inhibited the activities of both constitutive COX (COX­I) and inducible COX (COX-2) in a concentration-dependent manner, with the 50 values of about 0.8 and 2M, respectively. Lineweaver-Burk plot analysis indicated that CME competitively inhibited the activities of both COX-l and -2. This study is a first demonstration that CME directly inhibits COX activity.

• 한국항행학회논문지
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• 제15권1호
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• pp.97-103
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• 2011

본 논문은 비선형 위상 특성을 갖고 있는 CRLH 전송선로를 이용하여 이중대역 평형 믹서를 제안한 것이다. 이 메타 재질 구조의 믹서는 이중대역에서 낮은 LO 누설 전력과 높은 RF-LO 고립도를 갖고 있어, LO와 RF 경로에 추가적인 여파기가 필요하지 않는다. 이 평형 믹서는 이중대역에서 동작하는 발룬과 윌킨슨 분배기를 이용하여 구현하였으며, 이중대역 특성은 CRLH 전송선로의 비선형 위상 특성을 이용하였다. 제안한 메타 재질을 이용한 평형 믹서는 실험을 결과를 통해서 증명하였으며, 870 MHz와 1660 MHz의 주파수에서 동작하도록 제작하여, 870 MHz에서 15.2 dB, 1660 MHz에서 21.2 dB의 변환 손실을 얻었다.

• Journal of Plant Biotechnology
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• 제42권4호
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• pp.388-395
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• 2015

본 연구는 약용 및 식용으로 유망한 음나무의 대량생산 및 생식질 보존을 위한 기초 자료를 제공하기 위해 배발생 조직을 재료로 저온저장 기간별 SE 유도 및 식물체 재생을 시험하였다. 배발생 캘러스는 저온저장 6개월까지 정상적인 체세포배 형성이 가능하였으나 유도 빈도는 저장 기간에 따라 감소하는 경향을 보였다. 배발생능이 가장 좋은 ZE 10 세포주은 체세포배 유도 빈도에 있어 저장 기간에 따른 감소폭이 비교적 적은 것으로 나타났다. 체세포배의 발아 및 식물체 재생은 캘러스의 저장기간에 따라 다소 감소하는 경향을 보였으나 발아율은 93% 이상, 식물체 재생율은 91% 이상으로 저온저장에 따른 큰 문제는 없었다. 조직검경 결과 저장 기간에 따라 세포의 갈변화 및 활력 저하가 나타났으며, 아세토카민과 에반스블루의 염색을 통해서도 확인되었다. 이상의 결과로 볼 때 음나무 배발샐 캘러스의 저온저장은 계대배양 없이 $4^{\circ}C$의 냉장고에서 6개월 까지 가능한 것으로 나타났으며, 저장 후 체세포배 유도효율을 위해 배발생능이 양호한 세포주의 저장이 필요한 것으로 관찰되었다.