• 한국전기전자재료학회논문지
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• 제29권12호
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• pp.814-818
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• 2016

DSSCs (dye-sensitized solar cells) based on $TiO_2/SiO_2$ multi layer AR (anti-reflection) coating on the outer glass FTO (fluorine-doped tin oxide) substrate are investigated. We have coated an AR layer on the surface of a DSSCs device by using an IAD (ion beam-assisted deposition) system and investigated the effects of the AR layer by measuring photovoltaic performance. Compared to the pure FTO substrate, the multi layer AR coating increased the total transmittance from 67.4 to 72.9% at 530 nm of wavelength. The main enhancement of solar conversion efficiency is attributed to the reduction of light reflection at the FTO substrate surface. This leads to the increase of Jsc and the efficiency improvement of DSSCs.

• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.212-216
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• 1997

A new metal tip fabrication process for low voltage operation is reported in this paper. The key element of the fabrication process is that isotropic silicon etching and oxidation process used in silicon tip fabrication is utilized for gate hole size reduction and gate oxide layer. A metal FEA with 625 tips was fabricated in order to demonstrate the validity of the new process and submicron gate apertures were successfully obtained from originally 1.7$\mu\textrm{m}$ diameter mask. The emission current above noise level was observed at the gate bias of 50V. The required gate voltage to obtain the anode current of 0.1${\mu}\textrm{A}$/tip was 74V and the emission current was stable above 2${\mu}\textrm{A}$/tip without any disruption. The local field conversion factor and the emitting area were calculated as 7.981${\times}$10\ulcornercm\ulcorner and 3.2${\times}$10\ulcorner$\textrm{cm}^2$/tip, respectively.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.1973-1978
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• 2008

The NOx emission characteristics of DME in counterflow nonpremixed flames were investigated numerically, and brief experiments were carried out to compare the flame shapes and NOx emissions with those of $C_3H_8$ and $C_2H_6$. The DME flames were calculated using Kaiser's mechanism, while the $C_2H_6$ flames were calculated using the $C_3$ mechanism. These mechanisms were combined with the modified Miller-Bowman mechanism for the analysis of NOx. Experimental results show that DME flame has the characteristics of partial premixed flame and the flame length becomes very shorter compared with general hydrocarbon fuels and then, the NOx emission of DME is low as much as 60% of $C_3H_8$. In the calculated results of counterflow nonpremixed flames, the EINO of DME nonpremixed flame is low as much as 50% of the $C_2H_6$ nonpremixed flame. The cause of $EI_{NO}$ reduction is attributed mainly to the characteristics of partial premixed flame due to the existence of O atom in DME and partly to the O-C bond in DME, instead of C-C bond in hydrocarbon fuels.

• 약학회지
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• 제51권6호
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• pp.476-481
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• 2007

A polymorphic fungus, Candida albicans, causes various forms of infections such as disseminated candidiasis and vaginitis. Recent reports indicate that the fungus is a main etiological agent for the arthritis. In search of new sources for treatment of the fungal arthritis, we examined $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) against C. albicans-caused septic arthritis. The compound is isolated from Glycyrrhizae Radix that is known to have various immunomodulating activities and is one of the most popular herbal medicines. For induction of animal model of a septic arthritis, mice were given an emulsion form of C. albicans cell wall mixed with Complete Freund's Adjuvant (CFA) via footpad-injection. To determine prophylactic and therapeutic effects, the component was given to the animals before or after the induction of the arthritis, respectively. Data showed that intraperitoneal administration of $18{\beta}$-GA resulted in reduction of the inflammation, indicating the component had both prophylactic and therapeutic activities. For investigation of mechanism of the $18{\beta}$-GA, inhibitory effects on NO (nitiric oxide) and on T-lymphocyte proliferation were determined. Results demonstrated that $18{\beta}$-GA suppressed NO production from LPS (lipopolysaccharide)-treated macrophages and also inhibited proliferation of Con A (concanavalin A)activated T-cells. Taken together, $18{\beta}$-GA, a pentacyclic triterpene, has anti-arthritic activity against C. albicans-caused septic arthritis, possibly by blocking NO production and T-cell suppression.

• 대한화학회지
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• 제57권5호
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• pp.533-539
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• 2013

변전위법과 전기화학 임피던스 측정법을 이용하여 borate 완충용액에서 니켈 회전원판전극의 전기화학적 부식과 부동화를 연구하였다. Tafel 기울기, 임피던스, 회전원판전극의 회전속도, 그리고 부식전위와 부식전류의 pH 의존성으로부터 니켈의 부식과 부동화 반응 메커니즘과 환원반응에서의 수소 발생 반응구조를 제안하였다. EIS data로부터 등가회로를 제안하였으며 산화반응의 영역별로 전기화학적 변수들을 측정하였다. 부동화 반응에 의하여 생성된 $Ni(OH)_2$ 산화피막은 전기장의 영향을 받는 탈수반응에 의해 NiO로 전환되는 것으로 보인다.

• 한국재료학회지
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• 제24권1호
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• pp.43-47
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• 2014

NiO-doped hibonite pigments were synthesized by the solid state method to get stabilized blue color pigment in both oxidation and reduction atmospheres. Optimum substitution condition with NiO for hibonite blue pigment was investigated. Experimental results were comparable to those of previous cobalt-minimization studies performed with other phosphate- or oxide-based cobalt-containing ceramic pigments (having olivine ($Co_2SiO_4$), spinel ($CoAl_2O_4$), or with co-doped willemite ($(Co,Zn)_2SiO_4$) structures). Composition was designed varying the NiO molar ratio increasing with $SnO_2$. The optimum substitution content is 0.93 mole NiO with 0.75mole $SnO_2$. The characteristics of the synthesized pigment were analyzed by XRD, Raman spectroscopy, SEM, and UV-vis. Synthesized pigment was applied to a lime-barium glaze with 10 wt% each and fired at an oxidation atmosphere of $1250^{\circ}C/1h$ and a reducing atmosphere $1240^{\circ}C/1h$. Blue color was obtained with $L^*a^*b^*$ values at 43.39, -6.78, -18.20 under a reducing atmosphere and 41.66, -6.36, -14.7 under and oxidation atmosphere, respectively.

• Archives of Pharmacal Research
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• 제29권11호
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• pp.984-989
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• 2006

1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) has been characterized to have an anti-inflammatory activity through the inhibition of the production of nitric oxide and tumor necrosis $factor-{\alpha}$. In the present studies, the phase 1 metabolism of FPP-3 was investigated in rat liver microsomes and cytosols. When FPP-3 was incubated with rat liver microsomes and cytosols in the presence of NADPH. 2 major peaks were detected on a liquid chromatography/electrospray ionization-mass spectrometry. Two metabolites (i.e., M1 and M2) were characterized as reduced forms on propenone: M1 (1-furan-2-yl-3-pyridin-2-yl-propan-1-one) was the initial metabolite and M2 (1-furan-2-yl-3-pyridin-2-yl-propan-1-ol) was a secondary alcohol believed to be formed from M1.

• 한국정보통신학회논문지
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• 제3권1호
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• pp.235-244
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• 1999

본 논문에서는 새로운 동적 컴팩션(dynamic compaction) 알고리즘을 제안하고 이용하여 CMOS 디지털 회로의 IDDQ 테스트패턴 생성한다. 제안된 알고리즘은 프리미티브 게이트 내부에서 발생하는 GOS, 브리징 고장을 검출할 수 있는 프리미티브 고장패턴을 이용하여 초기 테스트패턴을 구하고, 초기 테스트패턴에 있을 수 있는 don't care(X)의 수를 줄여 테스트 패턴의 수를 감소시킨다. 그리고 난수와 4 가지 제어도(controllability)를 사용하여 백트레이스를 수행시키는 방법을 제안한다. ISCAS-85 벤치마크 회로를 사용하여 모의 실험한 결과 큰 회로에서 기존의 정적 컴팩션 알고리즘에 비하여 45% 이상 테스트패턴 수가 감소함을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계합동학술대회 논문집
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• pp.197-201
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• 2002

This paper presents optimized design, fabrication and thermal characteristics of micro-heaters for thermal MEMS (micro electro mechanical system) applications using SOI and trench structures. The micro-heaters are based on a thermal measurement principle and contains thermal isolation regions of 10 ${\mu}m$-thick Si membranes consisting of oxide-filled trenches in the SOI membrane rim. The micro-heaters were fabricated with Pt-RTD on the same substrate via MgO buff layer between Pt thin-film and $SiO_2$ layer. The thermal characteristics of micro-heater with trench-free SOI membrane structure was $280^{\circ}C$ at input power 0.9 W; in the presence of 10 trenches, it was $580^{\circ}C$ due to reduction of the external thermal loss. Therefore, a micro-heater with trenches in SOI membrane rim structure provides a powerful and versatile alternative technology for enhancing the performance of micro-thermal sensors and actuators.

• 한국분말재료학회지
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• 제12권2호
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• pp.146-150
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• 2005

An optimum route to synthesize $Al_2O_3$-based composite powders with homogeneous dispersion of carbon nanotubes (CNTs) was investigated. CNTs/Metal/$Al_2O_3$ nanocomposite powders were fabricated by thermal chemical vapor deposition of $C_2H_2$ gas over metal/$Al_2O_3$ nanocomposite catalyst prepared by selective reduction of metal oxide/$Al_2O_3$ powders. The FT-Raman spectroscopy analysis revealed that the CNTs have single- and multi-walled structure. The CNTs with the diameter of 25-43 nm were homogeneously distributed in the metal/$Al_2O_3$ powders, and their characteristics were strongly affected by a kind of metal catalyst and catalyst size. The experimental results show that the composite powder with required size and dispersion of CNTs can be realized by control of synthesis condition.