• 한국초전도학회:학술대회논문집
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• 한국초전도학회 1999년도 High Temperature Superconductivity Vol.IX
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• pp.261-261
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• 1999

We observed leveling-off of the resistance in granular In/InO$_x$ thin films in the zero-temperature limit. The temperature T$_b$ at which the leveling-off appears gets larger as the sheet resistance R$_n$ increases. This is consistent with the concept that the leveling-off of the resistance is due to the dissipation of the bosonic phase and that the dissipation is enhanced as the resistance increases. The magnetic field dependence of the saturated resistance R$_b$ at low temperatures fits the modified square-root cusp-like form R$_b$/R$_n$=α exp[-b(B/B$_c$-1)$^{-1/2}$] for the magnetic field in the range B$_c$$_f$ where B$_c$ is the onset magnetic field of the resistance leveling-off. α and b are constants of order 1. For B>B$_f$ tansport properties are described by the theory of the fermi insulator. From the results, we attribute the leveling-off to the dissipative quantum tunneling of vortices, which supports the models predicting the vortex-motion-induced insulating phase related with the concept like"dirty boson" [1]l and "hose metal" [2].

• 대한전자공학회논문지
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• 제25권11호
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• pp.1315-1322
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• 1988

$SnO_X$/Pt 薄膜형 가스感知素子의 製造하고 그 특성을 결정하였다. $SnO_X$/Pt 薄膜은 $SnO_2$에 Pt를 重量比로 2% 섞은 표적을 電子량 加熱승치法으로 形成하였다. 素子의 전도도는 온도의존성을 보였고, CO 가스에 대한 感度는 2000 ppm 이하의 낮은 농도범위에서 가스농도는 평방근에 비례하였다. 최적동작온도는 약 300$^{\circ}$C 였고 CO 가스농도가 5000 ppm에서의 응답시간은 약 20초 였다.

• 자원환경지질
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• 제20권1호
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• pp.77-82
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• 1987

전자탐사법에서 대표적인 4가지 루프시스템인 수평공면 루프, 직교루프, 수직공면루프 및 수직공측 루프의 지하박층 검색에 대한 상대적인 효율에 관하여 검토하였다. 3층 구조에 대한 상호전자결합의 절대치와 위상은 디지탈 필터법을 이용한 상관중합법으로 구하였으며, 4가지 시스템의 상대적인 효율은 3층구조와 균질구조에 대한 전자응답간의 표준편차로 정량적으로 비교하였다. 모든 시스템을 종합적으로 비교검토한 결과, 지하박층의 검색능력은 직교루프 시스템이 가장 우수한 것으로 나타났다.

• 생약학회지
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• 제4권4호
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• pp.193-203
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• 1973

The saponins of two- and four-year-old American ginseng plants (Panax quinquefolium L.) (Araliaceae) collected in July and September were studied. American ginseng saponins (panaquilins) differ from Korean ginseng $(Panax ginseng\;C.A.\;M_{EYER})$ saponins (ginsenosides). The American ginseng saponins separated and named were panaquilins A, B, C, D, E-1, E-2, E-3, G-1, G-2, (c) and (d). One-dimensional thin-layer chromatography did not completely separate panaquilin mixture and was subject to misinterpretation. The panaquilins were more accurately separated and identified by the two-dimensional thin-layer method established. Some differences in American ginseng saponins were dependent upon the plant age, time of collection, and part extracted. The American ginseng sapogenin components are panaxadiol (panaquilins B and C), oleanolic acid (panaquilin D) and panaxatriol (panaquilin G-1). The panaquilins E-1, E-2 and E-3 mixture contained both panaxadiol and panaxatriol. The genins of panaquilins A, (c), (d) and G-2 were not identified. In addition, ${\beta}-sitosterol$ and stigmasterol were identified from the root ether extracts.

• Applied Science and Convergence Technology
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• 제24권6호
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• pp.289-292
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• 2015

The etching processes of glass in aqueous hydrofluoric acid (HF) solutions were used to improve the current density of solar cell. In this study, the textured glass substrate has been etched by solution and the $TiO_2$ thin films have been prepared on this textured glass. After the $TiO_2$ film deposition the surface has been etched by HF under different concentration and the etched $TiO_2$ thin films had a longer electron lifetime and higher haze ratio as well as light scattering, resulting in 1.7 times increment of dye-sensitized solar-cell(DSSC) efficiency. Increases in the surface root-mean-square roughness of glass substrates from 80 nm to 1774 nm enhanced haze ratio in above 300 nm wavelength. In particular, haze ratio of etched $TiO_2$ films on textured glass showed gradually increasing tendency at 550 nm wavelength by increasing of HF concentration up to 10M, suggesting a formation of crater with various sizes on its surface.

• Journal of Welding and Joining
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• 제30권5호
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• pp.57-63
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• 2012

The purpose of this study is to evaluate the welding distortion of the circular type lap joint in STS304L of 0.7mm thickness by using FEA. In order to do it, a heat input model for GTA welding process with non-consumable electrode was established through comparing the molten pool shapes and temperature distributions obtained by both FEA and experiment. With the heat input model, the welding distortion of the circular type lap joint was evaluated by 3-D FEA. From FEA results, it was found that 3-D FEA with proper heat input model can be used for the evaluation of the excessive distortion of the circular type lap joint of STS304L thin plate. In addition, the root cause of the excessive distortion in the weld was also identified as the excessive compressive residual stress in the tangential direction of the weld.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.197-200
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• 2001

반응성 스퍼터링법으로 TaN film을 증착한 후 열처리온도에 따라 TaN 박막의 $R_s$(sheet resistance) 특성을 평가하고 미세구조 변화에 따른 전기적 특성 변화를 고찰하였다. TaN 박막을 열처리한 결과 $400^{\circ}C$에서 $600^{\circ}C$까지는 (110)의 회절피크만 보이다가 $700^{\circ}C$ 에서는 (200)의 회절 피크가 나타났고 특히 as-deposition 상태와 $300^{\circ}C$ 열처리시에는 Ta와 TaN 상이 혼재한 상태로 나타났으며 전기저항 변화는 as-deposition 상태가 $140{\Omega}/{\square}$로 가장 높았으며 열처리 온도가 증가함에 따라 저항은 점차적으로 감소하다가 $600^{\circ}C$와 $700^{\circ}C$에서는 전기저항이 다시 증가하였다. $500^{\circ}C$까지는 표면 형상이나 표면조도보다는 열처리 온도의 증가에 따른 TaN 박막의 결정구조 변화가 전기저항에 영향을 주는 주 요인으로 작용하고, $600^{\circ}C$와 $700^{\circ}C$ 열처리시에 결정립의 증가에도 불구하고 전기저항이 증가하는 것은 고온 열처리에 의한 표면조도가 증가하였기 때문이라고 생각된다.

• Applied Science and Convergence Technology
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• 제23권5호
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• pp.279-283
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• 2014

Al doped ZnO thin films have been deposited by a RF magnetron sputtering technique from a ZnO (2 wt.% $Al_2O_3$) target onto glass substrates heated at temperature ranging from RT to $400^{\circ}C$. X-ray diffraction analysis shows that the deposits have a preferential growth along the c-axis of a hexagonal structure. The full with at half maximum decreases from 0.45 to $0.43^{\circ}$ in the studied temperature range. The root main square surface roughness increases with substrate temperature from 1.89 to 2.67 nm. All films are transparent up to 80% in the visible wavelength range and the adsorption edge is red-shifted with substrate temperature from RT to $400^{\circ}C$. The sheet resistance increases from 92 ohm/sq to 419 ohm/sq when the deposition temperature increases from RT to $400^{\circ}C$. The increment of sheet resistance is caused by lowered carrier concentration resulting from an increase in surface roughness.

• 한국전기전자재료학회논문지
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• 제22권2호
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• pp.137-141
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• 2009

AZO transparent conductive thin films were grown on $SiO_2$/Si and glass substrates using diethylzinc (DEZ) and trimethylaluminium (TMA) as the precursor and $H_2O$ as oxidant by atomic layer deposition. The structural, electrical, and optical properties of the AZO films were characterized as a function of film thickness at a deposition temperature of $150^{\circ}C$. The AZO films with various thicknesses show well-crystallized phases and smooth surface morphologies. The 190-nm-thick AZO films grown on Coming 1737 glass substrates exhibit rms(root mean square) roughness of 8.8 nm, electrical resistivity of $1.5{\times}10^{-3}\;{\Omega}-cm$, and an optical transmittance of 84% at 600nm wavelength. Atomic layer deposition technique for the transparent conductive oxide films is possible to apply for the deposition on flexible polymer substrates.

• 한국식생활문화학회지
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• 제37권4호
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• pp.310-323
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• 2022

The purpose of this study was to investigate the preparation and cooking processes used to prepare Eungi in cookbooks published from the 1700s to the 1900s. 'Eungi' is a thin gruel made of starch powder. Fourteen historical cookbooks were included and investigated for the preparation of ingredients and processing methods. Fourteen types of eungi were identified. Arrowroot eui and kuseonwangdogo eui were found in 『Kyuhapchongseo』 written in the early 1800s, and many types of eungi (i.e. job's tears eungi, arrowroot eungi, sorghum eungi, lotus root eungi) were mentioned in 『Kunhakhoedeung』, but unfortunately, ingredients and cooking methods were not included. 'Eungi' was made by boiling starch powder prepared using the 'subi method', that is, dried after grinding main ingredients such as job's tears using a millstone followed by soaking and settling. Eungi boiled with water or omija water were seasoned with the sugar or honey, and salt. These eungis were used for stomach complaints and hangovers and to promote longevity.