• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.188-193
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• 1997

ZnO thin film had been deposited on the glass 7r sputtering method, and investigated by electrical and structural properties. When the rf power was 188W and sputtering pressure was 1$\times$10$^{-3}$ Torr at room temperature, Al-doped ZnO thin film had the lowest resistivity(1$\times$10$^{-4}$ $\Omega$.cm), and then carrier concentration and Hall mobility were 6.27$\times$10$^{20}$ cm$^{-3}$ and 22.04$\textrm{cm}^2$/V.s, respectively. And undoped ZnO thin film had about 10$^{14}$ $\Omega$.cm resistivity when oxygen content was 10% or more at room temperature. The surface morphology of ZnO thin film observed by SEM was overall uniform when oxygen content was 50% below and sputtering pressure was 1.0$\times$10$^{-1}$ Torr.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.284-285
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• 2006

We prepared ITO thin films using Facing Targets Sputtering(FTS) method with various input currents at room temperature on Polycarbonate(PC) and Polyethersulfon(PES) substrates. As a function of sputtering conditions, electrical and optical properties of prepared ITO thin films were measured. The electrical, optical, structural characteristics of ITO thin films were evaluated by Hall Effect Measurement(EGK), X-Ray Diffractormeter(Rigaku) and UV-VIS spectrometer(HP) respectively. From the results, we obtained ITO thin films that have a resistivity of $4{\times}10^{-4}[{\Omega}-cm]$ on PC and $527{\times}10^{-4}[{\Omega}-cm]$ on PES. Also, the optical transmittances of all samples were over 80%.

• 설비공학논문집
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• 제13권3호
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• pp.160-166
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• 2001

A numerical analysis has been performed for natural convection in an air conditioner duct system. The governing equations were solved a finite volume method using a SIMPLE algorithm. In the calculation mode of duct, the room temperature was preserved at $25.0^{\circ}C$ and duct wall temperature had a temperature of 15, 20.0, 22.5, 23.75, 26.25, 27.5 30 and $35^{\circ}C$. The results of velocity vectors and contours have been represented for various parameters. Based on the numerical data, the relationships between temperature difference and flow rate into room was represented. In the case of $T_\gamma>T_\omega$, the equation for temperature difference and flow rate was $Q=0.0285\triangleT^0.4005$, and in the case of $T_\gamma>T_\omega$, the equation was $Q=0.0099\triangleT^0.4752$. The duct system has an important relation to room temperature and duct wall temperature.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.924-927
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• 2003

Aluminium-doped ZnO (ZnO:Al) films were grown by atomic layer-controlled deposition on glass substrates at temperature of 200 $^{\circ}C$ using diethylzinc($Zn(C_{2}H_{2})_{2}$; DEtZn), water($H_{2}O$) and trimethylaluminium ($Al(CH_{3})_{3}$; TMA) as precursors. As the cycle ratio of TMA to DEZn(TMA/DEZn) increased, the resistivity of the films decreased and the roughness increased. In the case of TMA/DEZn pulse ratio of 1 to 10, the film had a resistivity of $9.7{\times}l0^{-4}{\Omega}{\cdot}cm$ and a roughness of 2.25nm(rms), while in the case of only DEZ injection the film had a resistivity of $3.5{\times}10^{-3}{\Omega}{\cdot}cm$ and a roughness of 1.07nm(rms)

• Journal of Advanced Marine Engineering and Technology
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• 제41권2호
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• pp.150-155
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• 2017

Many engineering issues are caused because of sloshing phenomena. Numerical solution methods including the computational fluid dynamics (CFD) technique, are used to analyze these sloshing problems. In this study, a numerical technique was used to analyze sloshing impact loads in a prismatic tank under forced horizontal motion. The volume-of-fraction (VOF) method was adopted to model the sloshing flow. Six cases were used to compare the effects of the natural frequencies of a simple rectangular and prismatic tank, with impact pressure on the prismatic tank wall. This study also investigated the variable pressure loads and sloshing phenomena in prismatic tanks when the frequencies were changed. The results showed that the average of the peak pressure value for ${\omega}^{\prime}1=4.24=4.24$ was 22% higher than that of ${\omega}_1=4.6$.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.30-31
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• 2000

400DPI LED array was fabricated by using reactive ion etching(RIE) method. Material of fabricated LED array was used the GaP for green light emitting and had a homojunction structure. Each cells of emitting area in the LED array were defined with RIE etching for electrical isolation between cells. Electrodes were formed on each cells to emit independently. Ohmic contact resistivity was approximate 1.2$\times$10$^{5}$ $\Omega$/$\textrm{cm}^2$ and 1.26$\times$10$^{5}$ $\Omega$/$\textrm{cm}^2$ using isothermal annealing at 38$0^{\circ}C$ and 43$0^{\circ}C$. Emitting intensity of each etmitting cell was 1.65 cd/$m^2$.

• 소음진동
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• 제9권1호
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• pp.174-183
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• 1999

An analytical model for the lateral vibration of beams with a bonded lap joint and partial layered dampers has been proposed in this paper. Both shear and normal forces acting along the interface between the elastic and viscoelastic layers were considered in the vibration analysis. Analytical results were compared with those obtained by a finite element method. Effects of the size and location of layers in partial dampers on system loss factor($\eta_s$) and resonant frequency($\omega_r$) were studied. which showed that partial dampers adhered to the site exhibiting the maximum amplitude of vibration were most influential in the increase of $\eta_s$ and the decrease of $\omega_r$. Specific system loss factor( $\eta_s$ divided by total mass of system) was also evaluated in the analysis.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1273-1274
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• 2015

본 논문에서는 주파수 무관(frequency independence) 특성을 갖는 자기상보 구조(self-complementary structure)로 된 안테나의 급전선로(feed line)로 사용할 수 있는 초광대역 발룬(ultra-wideband balun)을 제안하였다. 발룬을 설계하기 위해 클로펜스타인 테이퍼(Klopfenstein taper)를 사용하여 임피던스 프로파일(impedance profile)을 구하고 이를 평행 스트립 선로(parallel strip line) 구조로 구현하기 위해 등각사상방법(conformal mapping method)을 이용했다. 설계한 발룬을 직접 제작하여 측정한 결과, 대역폭은 반사손실 -10 dB를 기준으로 할 때 0.45~10.53 GHz까지 10.08 GHz로 나타나, UHF(ultra high frequency) 통신대역에서 UWB(ultra-wideband) 통신대역에 이르기까지 매우 넓은 주파수 범위에서 자기상보형 안테나의 입력 임피던스 $188{\Omega}$을 $50{\Omega}$의 특성 임피던스에 정합시킬 수 있음을 확인하였다.

• 대한수학회논문집
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• 제9권2호
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• pp.423-438
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• 1994

We employ the Galerkin method to solve the nonlinear Urysohn integral equation (1.1) x(t) = f(t) ＋ $∫_{D}$ k(t, s, x(s))ds (t $\in$ D), where D is a bounded domain in $R^{d}$ , the function f and k are known and x is the solution to be determined. We assume that D has a locally Lipschitz boundary ([1, p. 67]). We can rewrite (1.1) in operator notation as x = f ＋ Kx. We consider (1.1) as an operator equation on $L_{\infty$}$(D) and assume that K is defined on the closure $\Omega$ of a bounded open set $\Omega$ ⊂ $L_{\infty}$(D). Throughout our analysis we put the following assumptions on (1.1).(omitted)(1.1).(omitted)

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.113-117
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• 1994

In this paper, an experiment about humidity sensing properties of oxide aluminum films by Anodic oxidation method was made. The humidity sensing properties of films were investigated in the relative humidity range of 10∼85(%RH) , changing the frequency from 1[kHz] to 100[kHz]. The impedance of humidity sensing films were decreased in accordance with the increase of relative humidity. The decreasing rate of impedance were larger at low measuring frequency. The decreasing difference changes from 17.7M$\Omega$ to 3.68M$\Omega$ at low measuring frequency.