• Transactions on Electrical and Electronic Materials
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• 제12권4호
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• pp.164-168
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• 2011

Nanocrystalline cadmium sulphide (CdS) thin films were prepared using chemical bath deposition (CBD), and the structural, optical and photoconductive properties were investigated. The crystal structure of CdS thin film was studied by X-ray diffraction. The crystallite size, dislocation density and lattice constant of CBD CdS thin films were investigated. The dislocation density of CdS thin films initially decreases with increasing film thickness, and it is nearly constant over the thickness of 2,500 ${\AA}$. The dislocation density decreases with increasing the crystallite size. The Urbach energies of CdS thin films are obtained by fitting the optical absorption coefficient. The optical band gap of CdS thin films increases and finally saturates with increasing the lattice constant. The Urbach energy and optical band gap of the 2,900 A-thick CdS thin film prepared for 60 minutes are 0.24 eV and 2.83 eV, respectively. The activation energies of the 2,900 ${\AA}$-thick CdS thin film at low and high temperature regions were 14 meV and 31 meV, respectively. It is considered that these activation energies correspond to donor levels associated with shallow traps or surface states of CdS thin film. Also, the value of ${\gamma}$ was obtained from the light transfer characteristic of CdS thin film. The value of ${\gamma}$ for the 2,900 A-thick CdS thin film was 1 at 10 V, and it saturates with increasing the applied voltage.

• 혜화의학회지
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• 제19권1호
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• pp.87-98
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• 2010

There are four kinds of diagnosis methods in oriental medicine, and viewing diagnosis(望診) is the most important method among them. There are two ways in viewing diagnosis. These are viewing shape(觀形) and inspecting color(察色). Viewing shape diagnosis includes observation on geometric curve that is made by prominence of bones or lump of flesh, and examination on symmetric disparity and balance of vertical length among three vertical section of face. Inspecting color is literally inspecting several specified region of face. By Viewing shape, we can learn about characteristic physical mechanism of individuals, and basic disposition of reaction from inside and outside infinite stimulations. On the other hand, by inspecting color, we can estimate the very present pathologic and physiologic status of the patient. the estimation is based on principle that inside body changes reveal some reflections on facial skin surface. When you diagnosis patients with inspecting color method, It is important to distinguish color delicately, and to know where to see and what to know from it. The most important and frequently mentioned regions are myong-dang(明堂), eyes(眼) and In-dang(印堂). Myong-dang(明堂) indicates nose. In-dang(印堂) indicates the space between eyebrows. Unlike myong-dang(印堂) and eyes, In-dang(印堂) is occasionally treated as a trivial region then others. But, from research on classical books of facial examination and consideration of it's locational meanings, we've learned In-dang(印堂) is very important in viewing diagnosis, because this region is crossing of the other two regions and this fact means this region expresses the spiritual status as well as physical status in one region.

• 한국의류산업학회지
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• 제8권3호
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• pp.343-348
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• 2006

This study aims to attain gray tone dyed goods by using tannin that is contained in green tea. Tannin is given general name of polyphenol, which has a characteristic that bonds with protein and it is used for food preservative that protects against bacteria, as well as its purpose of black tone dye for silk treatment that has been processed since its early ages. In particular, as tannin reacts with all kinds of metallic mordant and changes to various colors, when tannin acid is combined with iron, it becomes tannin steel and produces gray tone color. Tannin that is contained in green tea is condensed tannins and its structure does not hydrolyze, thus having flavan type structure. In order to find the suitable condition for processing tannin, UV-Vis part absorption spectrum of green tea tannin, dye ability based on temperature and time, reflection rate based on concentration, color changes based on acid treatment and alkali treatment, changes on surface based on concentration or metal mordant condition, and lightfastness were measured. Maximum absorption wavelength (${\lambda}_{max}$) of green tea tannin was at around 273nm, while strong absorption was also observed at below 350 nm. Dye ability of green tea tannin is done more easily on silk rather than cellulose fibers such as cotton, while the optimum condition for dyeing was observed to be at $60^{\circ}C$, for 20 minutes. As a result of acid treatment, the color of dye material consisted highly of gray tones and showed overall gray tone with the combined color of yellow and red after the alkali treatment. While it was observed that as dye concentration and metal mordant concentration increased, the color changed at counter-clockwise direction on the Y-scale of Munsell's scale of colors. Additionally, lightfastness was more on a normal fading.

• 한국철도학회논문집
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• 제12권2호
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• pp.321-328
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• 2009

기존 터널에 근접하여 절리암반 굴착시 사면의 적절한 보강방법 및 시기는 굴착사면과 터널과의 근접도, 굴착사면 경사는 물론 절리상황에 의해 영향을 받자만 현재까지는 경험적으로 결정되고 있다. 본 연구에서는 터널에 근접하여 절리암반 지반을 굴착시 굴착단계에 따른 굴착사변에서의 하중전이 특성과 터널거동과의 상관관계를 분석하기 위하여 절리각도와 굴착사면 경사를 영향인자로 한 대형 모형시험을 실시하였다. 시험결과, 터널변형은 터널 천정부 또는 바닥부에 근접한 절리면 굴착시 가장 크게 발생을 하였으며, 사면과 터널의 안정성은 굴착사면의 경사와 관련하여 굴착단계에 따라 변화하였다. 향후 본 연구결과를 활용하여 절리암반에서의 터널과 사면의 보강방안을 도출하고자 한다.

• 대한화장품학회지
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• 제18권1호
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• pp.1-41
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• 1992

A new and unique class of nonionic surfactants was synthesized by reacting biological a-tocopherol with ethylene oxide for functional cosmetics. The structures were confirmed by Hl-UMR, FT-lR, TLC and elemental analysis. POV and conjugated diene value study for EPO showed POE(n)TE had antioxidative effect similar to tocopheryl acetate Protective effect on cell membrane in photohemolysis of POE(5)TE, POE(10)TE and POE(18)TE were slightly lower than tocopherol but higher than nonoxynol-12, and POE(10)TE had UV absorption power comparable with tocopherol and homosalate. Biological activity of the hydrophobic group of the new surfactants make them unique and different from those of conventional nonionic surfactants Systematic safety evaluations of POE(n)TEs on the skin and eye proved that they are as safe as tocopherol. The results of physicochemical study showed POE(10)TE had the lowest CMC value, POE(18)TE had the maximum surface tension reduction and the highest foam volume and POE(n)TEs had various HLB values by the degree of ethoxylation. The test resul Is of technological and practical applications of these surfactants for cosmetics showed some POE(n)TEs were superior to conventional surfactants. POE(5)TE in W/O emulsions, POE(10)TE and POE(12)TE in O/W emulsions, POE(12)TE in dispersions, POE(18)TE in solubilizations and POE(50)TE in gelations were shown to be excellent which was considered due to the structural characteristic and formation of liquid crystals of POE(n)TEs. By the development and applications of these excel lent multi-functional surfactants, innovative functional cosmetics were successfully formulated.

• 반도체디스플레이기술학회지
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• 제4권2호
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• pp.39-43
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• 2005

In the study, in order to deposit TaN thin film for diffusion barrier and bottom electrode we made the Plasma Assisted ALD equipment and confirmed the electrical characteristics of TaN thin films grown PAALD method. Plasma Assisted ALD equipment depositing TaN thin film using PEMAT(pentakis(ethylmethlyamino) tantalum) precursor and NH3 reaction gas is shown that TaN thin film deposited high density and amorphous phase with XRD measurement. The degree of diffusion and reaction taking place in Cu/TaN (deposited using 150W PAALD)/$SiO_{2}$/Si systems with increasing annealing temperature was estimated for MOS capacitor property and the $SiO_{2}$, (600${\AA}$)/Si system surface analysis by C-V measurement and secondary ion material spectrometer (SIMS) after Cu/TaN/$SiO_{2}$ (400 ${\AA}$) layer etching. TaN thin film deposited PAALD method diffusion barrier have a good diffusion barrier property up to 500$^{\circ}C$.

• 대한전자공학회논문지SP
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• 제38권3호
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• pp.292-303
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• 2001

임의의 물체색은 장면(scene)에 존재하는 조명과 물체 표면의 특성에 의해 결정되므로, 정확한 물체색을 표현하기 위해서는 조명색의 추정이 중요하다. 본 논문은 인지광원(perceived illumination) 현상을 확장한 방법과, 광휘점(highlight) 방법을 각각 제안하고, 두가지 방법을 결합하는 결합적 조명색 추정방법을 제안한다. 인지광원 방법은 개략적인 해의 범위를 결정하는 면에서는 안정성이 보장되나, 정확성의 측면에서는 입력영상의 내용에 의존적인 경향이 있는 단점이 있다. 광휘점 방법은 입력영상의 내용에 의존적이지 않으며, 정확한 해를 제시하는 장점이 있으나, 최종적인 해를 결정하기 위해 폭넓은 범위를 가지는 교차점인 다수의 후보들을 고려해야 하는 단점이 있다. 그러므로 본 논문에서는 두 가지 방법의 상호보완적인 특성을 이용하여, 인지광원 방법의 추정결과를 가능한 해의 개략적인 범위로 설정하고, 광휘점 방법으로부터 추출된 후보점 및 분포 클러스터(cluster)들의 특성을 고려하여 최종적인 해를 결정하는 알고리즘을 제안한다.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2403-2407
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• 2013

The hybrid density-functional (B3LYP/6-31G(d,p)) method was used to analyze the substitution effect on the $C_{20}H_{20}$ cage based on calculation of the frontier orbitals of fifteen $C_{20}H_{17}(OH)_3$ derivatives. All substitution products were geometrically optimized without constraints and confirmed by frequency analysis. The results suggest that the cis-1 cis-1 cis-2 regioisomer is the most stable isomer, which implies that hydrogen bonding exerts a stronger effect on the relative energies of the trihydroxide than long-range interactions. Thus, this supports the experimental result in which the bisvicinal tetrol was of particular preparative-synthetic interest. While the LUMO of each of the $C_{20}H_{17}(OH)_3$ regioisomers was equivalently delocalized over the void within the cage, the HOMO was limitedly delocalized on substituents and carbons in close proximity to the substituents. The characteristics of the HOMO of each of the regioisomers vary based on the substitution sites. This indicates that the 15 regioisomers of each $C_{20}H_{20}$ trisubstituted derivative might undergo an entirely different set of characteristic chemical reactions with electrophilic reagents. The results further suggest that the penta-substituted OH groups on the surface of the fullerene cage are more likely to be localized on a pentagon than to be homogeneously delocalized.

• 항공우주기술
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• 제1권2호
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• pp.123-131
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• 2002

본 논문에서는 KSR-III 주 엔진 연소시험설비를 활용한 수류시험 및 연소시험 과정에서 극저온 추진제인 액체산소의 냉각단계, 충진단계, 연소시험 공급 단계에서 액체산소의 상태량을 시험설비의 각 위치에서 분석함으로써 향후 안정된 공급을 위한 설비 및 운용조건을 선정하는데 주안점을 두었다. 이를 위해 각 단계에서 기체와 극저온 추진제의 상호 작용이 발생하는 가압탱크에서의 가압기체 및 액체산소의 상태량을 파악하였으며, 연소시험시 엔진 메니폴드에서의 액체산소의 상태량을 분석하였다. 또한 냉각 및 충진시에 대기압 vent에 액체산소의 거동을 파악함으로서 냉각을 효율적으로 할 수 있는 방안을 분석하였다. 또한 산소 공급 설비와 로켓엔진 매니폴드에 정압센서와 동압센서를 장착하여 1KHz의 sampling rate로 측정하였다. 오리피스 사이즈는 지름 32.5mm 38mm, 가압 압력 23Bar, 29Bar, 41Bar에 대해 시험을 수행하였다. 오리피스 사이즈를 증가시키고 가압 압력을 낮춘 결과 엔진 내에 공급되는 액체산소의 섭동량이 감소하는 것이 관찰되었다.

• 한국음향학회지
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• 제20권1호
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• pp.68-76
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• 2001

유한요소법을 이용하여 압전 수중음향센서의 모델링 및 음향특성을 해석하였다. 압전 수중음향센서의 해석에서 기본적인 압전-탄성 구조물과 유체-구조물의 연성해석을 위한 유한요소 정식화를 하였으며 무한영역의 음향유체를 처리하기 위하여 IWEE (Infinite Wave Envelop Element)를 도입하였다. Tonpilz형 수중음향센서를 수중 산란체로 볼 경우 입사파가 산란체의 표면을 가진할 때 산란체로부터 발생되는 산란파는 IWEE로 인하여 무한 유체영역에서의 산란파의 감소특성을 갖게 되어 무한영역을 유한영역으로 나눈 인위적인 경계에서 반사가 일어나지 않게 되므로 산란파의 음압을 정확히 구할 수 있었다. 또한, 이러한 산란해석을 바탕으로 입사파에 대한 음향센서 내부의 전기적 응답특성인 RVS (Receiving Voltage Signal)를 구하였다. 이러한 일련의 연구 과정들은 소나 시스템을 정확히 해석하고 음향특성을 예측하는데 큰 도움이 될 것이다.