• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.471-471
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• 2013

Highly stable and high performance amorphous oxide semiconductor thin film transistors (TFTs) were fabricated using 4-mercaptophenol (4MP) doped ZnO by atomic layer deposition (ALD). The 4 MP concentration in ZnO films were varied from 1.7% to 5.6% by controlling Zn: 4MP pulses. The carrier concentrations in ZnO thin films were controlled from $1.017{\times}10^{20}$/$cm^3$ to $2,903{\times}10^{14}$/$cm^3$ with appropriate amount of 4MP doping. The 4.8% 4MP doped ZnO TFT revealed good device mobility performance of $8.4cm^2V-1s-1$ and on/off current ratio of $10^6$. Such 4MP doped ZnO TFTs were stable under ambient conditions for 12 months without any apparent degradation in their electrical properties. Our result suggests that 4 MP doping can be useful technique to produce more reliable oxide semiconductor TFT.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2000년도 정기총회 및 학술대회
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• pp.101-106
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• 2000

본 논문에서는 MPEG-4 데이터를 MPEG-2 A/V 스트림에 효율적으로 삽입하기 위한 방안을 제안한다. 제안된 방법은 mp4 파일로부터 MPEG-4 객체인 IOD(Initial Object Descriptor), OD(Object Descriptor), BIFS(Binary Format for Scene) 및 미디어 데이터를 추출해 낸 후, MPEG-2 TS 프로토콜을 이용하여 사용자가 원하는 시간에 MPEG-4 데이터를 재생할 수 있도록 MPEG-2 A/V 스트림과 동기화하여 전송하는 기술이다.

• 디지털콘텐츠학회 논문지
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• 제3권2호
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• pp.163-176
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• 2002

통신망에서 Internet Protocol version 4(IPv4)에서 IPv6로의 전환은 필수적이나 실제 상용망에서는 적용되지는 않고 있고 현재 실험망으로만 가동되고 있다. 본 논문에서는 Internet Protocol version 4(IPv4)의 한계로 인해 등장한 새로운 프로토콜인 IPv6로의 변환이 필요한 시점에서 IPv6에 대하여 살펴보고, 보안 문제를 일으킬 수 있는 프로토콜의 요소를 사전에 예측하게 함으로써 IPv6 망으로의 전환시 유 무선 환경에 있어 안전한 전환을 위한 사전 시험 기능을 제시한다.

• 대한화학회지
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• 제45권6호
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• pp.532-537
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• 2001

H-chelate형태의 2-Quinazolylacetonitrile유도체들은 2-cyanomethylquinazoline에 여러가지 친전자체들, 즉, 4-chloroquinazoline, 4-chloro-2-phenylquinazoline, 4,6-dichloropyrinidine, 4,6-dichloro-2-phenylpyrimidine, 4,6-dichloro-5-phenylpyrimidine, 2-chloroauinoxaline,1,3- dichloroisoquinoline, 2,6-dichloropyrazine, 2-chloropyrazine, 4,6-dichloro-2,5-diphenylpyrimidine 등을 반응시켜 얻을 수 있었다. 합성된 H-chelate화합물들은 polymethine계의 발색단 구조를 가지게 된다. 이들 화합물에 대한 구조는 분광학적인 방법으로 분석 확인 하였다.

• 대한화학회지
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• 제38권1호
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• pp.61-68
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• 1994

Fe(0)촉매하에서 이중고리 생성물이 얻어지는 acetylenic diene을 반응시켜 분자내 [4+2]고리화 첨가반응을 조사하였다. 위 반응은 이분자 첨가반응과 분자내 탄소 고리화 반응이 경쟁적으로 진행된다고 알려져 있다. 그러나 Fe(0)촉매하에서 4,4-dimethyl-3-(tert-butyldimethylsiloxy)-1-phenyl-6,8-decadien-1-yne(11)의 고리화 반응은 단지 이중고리 생성물만이 얻어졌다(수득율 78.1%). 이 결과에서 dienyne의 4,4-위치에 치환된 dimethyl기가 Fe(0)촉매하의 고리화 반응조건에 안정함으로 인하여 분자내 고리화 반응이 촉진되는 것으로 생각된다.

• 한국축산식품학회지
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• 제31권3호
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• pp.381-388
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• 2011

Dietary conjugated linoleic acid (CLA) play key roles in lipid metabolism. Here, we investigated the effect of CLA on the transcriptional activity of TR4, an orphan nuclear receptor that plays an important role in lipid homeostasis. CLA increased TR4 gene mRNA level in 3T3-L1 adipocytes, but inhibited TR4 transcriptional activity in a dose-dependent manner. TR4 induced perilipin expression in 3T3-L1 adipocytes by activating perilipin promoter activity. In a gel shift assay, TR4 bound direct to the putative TR4 response element in the perilipin promoter. Interestingly, CLA reduced the interaction between TR4 and consensus DR1, a well-known TR4 binding site. Additionally, CLA inhibited TR4-induced perilipin promoter activity in a dose-dependent manner. Together, our results suggest that CLA may play a role in lipid homeostasis in adipocytes by functionally regulating TR4.

• Macromolecular Research
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• 제9권5호
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• pp.247-252
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• 2001

Tricyclic aliphatic dianhydride monomer, tricycle[4.2.2.0]dec-9-ene exo, endo-3,4: 7,8-tetra-carboxylicdianhydride (TCDDA), was synthesized by photochemical reaction and poly(amic acid)s from TCDDA and diamines such as 1,4-bis-(4-aminophenoxy)benzene (BAB), 2,2-bis(4-(4-aminophenoxy) phenyl) propane (BAPP), 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane (BAPHF), bis(4-(4-ami-nophenoxy) phenyl)sulfone (BAPS), and 1,4-bis-(4-aminophenoxy)biphenyl (BABP) were prepared. The inherent viscosities of the poly(amic acid)s were between 0.39 and 0.50 dL/g. The poly(amic acid)s were converted to polyimide films by thermal imidization. The glass transition temperatures (T$\_$g/) of the polyimides were in the range of 201-263$\^{C}$. The thermogravimetric analysis (TGA) thermogram of these polyimides showed the temperatures of 5% weight losses between 375 and 393$\^{C}$ in nitrogen atmosphere. To show their utility for image generation, degradations of these polyimides in UV exposure were investigated by UV spectroscopy.

• 대한화학회지
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• 제35권5호
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• pp.575-579
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• 1991

6${\beta}$-bromopenicillanic acid(4a)와 p-nitrobenzylbromide, 3-bromophthalide, chloromethylpivalate 및 1-chlorodiethylcarbonate의 반응으로 6${\beta}$-bromopenicillanates(4b~4e)을 합성하였으며, 6${\beta}$-bromopenicillanic acid(4a)와 그의 ester(4b~4e)를 thioglycolic acid와 친핵성 치환반응시켜 새로운 $\beta$-lactam계 화합물인 6-(carboxymethylthio)penicillanic acid(5a)와 그의 ester(5b~5e)를 얻었다.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.985-989
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• 2003

An efficient synthesis of 5-chloro-3-[4-(3-diethylaminopropoxy)benzoyl]-2-(4-methoxyphenyl)benzofuran (8), a potent $\beta$-amyloid aggregation inhibitor, is described. 5-Chloro-2-(4-methoxyphenyl)benzofuran (3) was obtained by the one-pot synthesis of 4-chlorophenol with $\omega$(methylsulfinyl)-p-methoxyacetophenone (1) under Pummerer reaction conditions, and it was followed by the desulfurization of the resultant 5-chloro-3-methylthio-2-(4-methoxyphenyl)benzofuran (2e). Acylation of benzofuran 3 with 4-(3-bromopropoxy)benzoyl chloride (6) gave the ketone 7, which was converted into compound 8 by the treatment of diethylamine.

• 약학회지
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• 제35권3호
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• pp.231-235
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• 1991

Compounds of the structure of -4,9-dione are known to have an antibacterial activity against Gram-positive bacteria. New kinds of 2-amino-$\alpha$-cyano-$\alpha$-ethoxycarbonyl-niethyl)-1,4-naphthoquino ne was reacted with some alkylamines(methylamine, ethylamine, ethanolarnine, isopropylamine, cyclohexylamine, benzylamine) to yield 2-amino-3-ethoxycarbonyl-N-alkyl-4,9-diones.