• 한국전산유체공학회지
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• 제7권1호
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• pp.36-43
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• 2002

A numerical investigation is made of unsteady double-diffusive convection of a Boussinesq fluid in a rectangular cavity subject to time-periodic thermal excitations. The fluid is initially stratified between the top endwall of low solute concentration and the bottom endwall of high solute concentration. A time-dependent heat flux varying in a square wave fashion, is applied on one sidewall to induce buoyant convection. The influences of the imposed periodicity on double-diffusive convection are examined. A special concern is on the occurrence of resonance that the fluctuations of flow and attendant heat and mass transfers are mostly amplified at certain eigenmodes of the fluid system. Numerical solutions illustrate that resonant convection results in a conspicuous enhancement of time-mean mass transfer rate.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.463-466
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• 2010

축열식 가열기 형태의 초음속 풍동을 이용하여 스크램제트 엔진 흡입구의 성능 연구를 수행하였다. 본 시험모델은 측벽배치변화가 성능에 큰 영향을 미치지 않는 것으로 나타났다. 격리부 성능연구에서는 Oblique shock train과 Normal shock train의 압력분포를 확인할 수 있었으며, 격리부의 불시동 한계성능을 분석하였다.

• 반도체디스플레이기술학회지
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• 제3권3호
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• pp.41-44
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• 2004

The aim of this study is the confirmation of the coating uniformity affected by the surface tension and wall attachment angle in a slit-coater model. In this work, we use the commercial code (Fluent) to solve the two-phase flow formed with air and photo resist numerically. The results show that the surface tension is the most important factor to determine the coating efficiency in the view of coating uniformity, and the coating uniformity is 2% for our slit-coater model and conditions. To improve the coating uniformity, it is in need of minimization of the sidewall effect of slit-coater.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2004년도 춘계학술대회 발표 논문집
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• pp.92-96
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• 2004

Scales, accumulated on semiconductor equipment parts during device fabrication processes, often lower equipment lifetime and production yields. Thus, many equipments parts have be cleaned regularly. In this study, an attempt to establish an effective process for the removal of scales on the sidewall of collimators in the chamber of sputter is made. The EDX analysis revealed that the scales are composed of Ti and TiN with the colummar structure. It was found that the heat-treatment at 700 for 1 min. after the oxide removal in the HF solution, and then etching in the HNO3 : H2SO4 : H2O =4:2:4 solution for 5.5 hrs at 67 was the most effective process for the scale removal.

• 한국정밀공학회지
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• 제20권10호
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• pp.120-129
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• 2003

For successful establishment of the roughing CAM system based on reverse engineering, it is necessary to develop the measurement method for generation of roughing path from a physical footwear model. In this study, the development of the roughing path measurement system is presented. It consists of 3 CCD cameras, image acquisition board and the roughing path measurement algorithm. The 3 CCD cameras capture images of the sidewall and the bottom of the footwear and, from two images, the outer and inner lines are extracted using image-processing algorithm. The roughing path measurement algorithm generates the roughing path which is reflected on the change of resolution according to the distance between the CCD camera and the measured point. The experimental results show that the developed system can measure the roughing path within the allowable roughing error range.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.759-762
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• 2000

Present transistors which have vertical structure show increased parasitic capacitance characteristics in accordance with the increase of non-active base area and collector area, consequently have disadvantage for high speed switching performance. In this paper, a horizontal structure transistor which has minimized parasitic capacitance in virtue of SDB(Silicon Direct Bonding) wafer and oxide sidewall isolation utilizing silicon trench technology is presented. Its structural characteristics were designed by ATHENA(SUPREM4), the process simulator from SILVACO International, and its performance was proven by ATLAS, the device simulator from SILVACO International. The performance of the proposed horizontal structure transistor was certified through the VCE-lC characteristics curve, $h_{FE}$ -IC characteristics, and GP-plot.

• 대한전기학회논문지
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• 제45권2호
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• pp.249-255
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• 1996

A self-aligned latch-up suppressed IGBT has been proposed and the process method and the device characteristics of the IGBT have been verified by numerical simulation. As the source is laterally diffused through the sidewall of the trench in the middle of the body, the size of the source is small and the doping concentration of the source is lower than that of the p++ body and the emitter efficiency of the parasitic npn transistor is low so that latch-up may be suppressed. No additional mask steps for p++ region, source, and source contact are required so that small sized body can be obtained Latch-u current density higher than 10000 A/cm$^{2}$ have been achieved by adjusting the process conditions.

• International Journal of Safety
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• 제8권2호
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• pp.20-25
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• 2009

In this study, an experiment in the field was performed to analyze the mechanical properties and the influence of steel fiber and silica fume on the rebound ratios of shotcrete. The experimental parameters which are the reinforcing methods (steel fiber, wire mesh), steel fiber contents (0.0%, 0.5%, 0.75%, 1.0%), silica fume contents (0.0%, 10.0%), layer thickness (60 mm, 80 mm, 100 mm), and the placing parts (sidewall, shoulder, crown) were chosen. From the mechanical test, it was found that the flexural strength and toughness is significantly improved by the steel fiber and/or silica fume. According to the results for the side wall in this test, the larger the fiber contents are in case of steel fiber reinforced shotcrete, the less the rebound ratios are within the range of 20-35%, compared to the wire mesh reinforced shotcrte. And also, the reduced rebound ratios were very larger in using steel fiber reinforced shotcrete with silica fume content of 10%, and these results are true of the shoulder and the crown. respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.284-285
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• 2007

In this paper, we present the effect on a novel transmission line filter response by the etch hole position on the suspended ground and the residue on the resonator under ground plane. We defined the etch hole offset as the distance from the sidewall of the suspended ground to the nearest side of the etch holes. We simulated new filter responses to reflect the real value of the changed etch hole offset caused by characteristics of negative photoresist. Return loss is distorted by the residue on the center conductor remained after sacrificial layer removing. By comparison of simulation and measurements, we concluded the residue on the resonator distorted the RF response worse than etch hole offset variation did.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.443-446
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• 2003

A 2-Dimensional SSIMT(Suppressed Sidewall Injection Magnetotransistor) sensor with high linearity is presented in this paper. The prototype is fabricated by using the Hynix $0.6{\mu}m$ CMOS Process. The fabricated SSIMT shows that the variation of each collectors current are extremely linear by varing the magnetic induction from -200mT to 200mT at $I_B\;:\;1000{\mu}A,\;V_{CE}\;=\;5V\;and\;V_{SUB}\;=\;5V$. The relative sensitivity is up to 13%/T. At B = 0, magnetic offset is about 40mT, there relative sensitivity is 4.72%/T. The nonlinearity of the fabricated 2-D SSIMT is measured about 1.2%.