• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.44-45
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• 2001

VOCs의 일종인 benzene을 흡수하기 위한 최적의 세정액으로 열매체유를 선정하여, 충진탑(Packed Tower), 흡수칼럼에 세정액만 채워 bubble 시킨 기포탑(Aeration Tower)와 충진물과 세정액을 채워 bubble 시킨 Combined Packed & Aeration Tower의 3가지 시스템을 비교한 결과 Combined Packed 쇼 Aeration Tower 시스템에서 benzene 흡수효율이 가장 좋았다.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.216-222
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• 2006

A flexile fiber filter developed in Korea was operated to evaluate the effect of packing density and filtration velocity on particle removal. The pilot-scale fiber filter with 40 cm of diameter and 2 m of height was packed with polyamide fibers of which mean diameter was approximately 0.93 mm. While the filtration velocity was maintained at 325 m/hr, the particle removal efficiency was compared with various of packing density from $70kg/m^3\;to\;100kg/m^3$. On the contrary, when the packing density was maintained at $70kg/m^3$, the particle removal efficiency was examined with various filtration velocity from 65 m/hr to 400 m/hr. The filtration pressure increased with the packing-density increase. Below $80kg/m^3$ of packing density, the removal efficiencies of turbidity ad SS were less than 30% and 50%, respectively. At $100kg/m^3$ of packing density, the removal efficiencies of them were nearly 45% and 60% respectively. The filtration pressure increased with the filtration-velocity increase. A better removal efficiency was obtained at a lower filtration velocity, removal efficiency of them were 73% at 65 m/hr. Consequently, The filtration velocity was the more important factor to enhance the particle removal efficiency compared with the packing density in fiber filter.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.239-241
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• 2009

DRIE(Deep Ion Reactive Etching) 공정은 실리콘 웨이퍼를 식각하는 기술로서 Si wafer 비아 홀 제조에 주로 사용되고 있다. 즉, DRIE 공정은 식각 및 보호층 증착을 반복함으로써 직진성 식각을 가능하게 하는 공정이다. 또한, 3차원 적층 실장에서 Si wafer 비아 홀에 결함없이 효과적으로 구리 충진을 하기 위해서는 직각형 via보다 경사벽을 가진 via가 형상적으로 유리하다. 본 연구에서는 3차원 적층을 위한 Si wafer 비아 홀의 결함 없는 효과적인 구리 충진을 위해, DRIE 공정을 이용하여 기존의 경사벽을 가지는 via 흘 형성 공정보다 더욱 효과적인 공정을 개발하였다.

• Journal of Korea Foundry Society
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• v.17 no.6
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• pp.552-559
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• 1997

주조방안설계를 위한 pre-processor, main-solver 그리고 post-processor로 구성된 통합 응고해석 시스템을 개발하였다. Pre-processor는 퍼스널 컴퓨터에서 사용되는 상용 CAD 프로그램인 AutoCAD를 사용하였다. Main-solver는 주조과정중의 충진거동을 해석한 유동해석 프로그램과 3차원 열전달 응고해석을 통합하여 냉각수 시스템으로 제어되는 금형 반복주조법에서의 응고양상을 해석할 수 있다. Post-processor는 cavity내의 용탕충진거동, 주형내의 온도분포, 응고시간등을 3차원 그래픽으로 처리할 수 있게 설계하였다. 개발된 시스템의 현장적용 가능성을 검증하기 위하여 대형주강 밀하우징, 자동차휠 주조용품, 밸브블럭등의 시제품의 열유동해석에 적용하였다. 본 연구에서 개발된 CastDesigner는 중소기업형 주조현장에서 PC용 CAD/CAE system 구축을 통한 최적주조방안 설계용 열유동해석 프로그램으로 사료된다.

• Food preservation and processing industry
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• v.14 no.2
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• pp.24-32
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• 2015

• Electrical & Electronic Materials
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• v.13 no.11
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• pp.1-11
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• 2000

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.406-413
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• 2022

The subsea pipeline pre-commissioning stage consists of the following processes: Flooding, Venting, Hydrotesting, Dewatering, Drying, and N2 Purging. Among these processes, drying and nitrogen purging processes are stipulated to reduce and maintain the relative humidity below dew point to prevent the generation of hydrate and the risk of gas explosion in the pipeline during operation. The purpose of this study is to develop an analysis method for the air drying and nitrogen purging process during pre-commissioning of the subsea pipeline, and to evaluate the applicability of the analysis method through comparison with on-site measurement results. An analysis method using Computational Fluid Dynamics (CFD) was introduced and applied as a method for evaluating the relative humidity inside a subsea pipeline, and it was confirmed that analysis results were in good agreement with the on-site measurement results for the air drying and nitrogen purging process of the offshore pipeline. If the developed air drying and nitrogen purging analysis method are used as pre-engineering tools for pre-commissioning of subsea pipelines in the future, it is expected to have a significant impact on the improvement of work productivity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.4
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• pp.141-147
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• 2018

Solar energy has attracted big attentions as one of clean and unlimited renewable energy. Solar energy is transformed to electrical energy by solar cells which are comprised of multi-silicon wafer or mono-silicon wafer. Monosilicon wafers are fabricated from the Czochralski method. In order to decrease fabrication cost, increasing a poly-silicon charge size in one quartz crucible has been developed very much. When we increase a charge size, the temperature control of a Czochralski equipment becomes more difficult due to a strong melt convection. In this study, we simulated a Czochralski equipment temperature at 20 inch and 24 inch in quartz crucible diameter and various charge sizes (90 kg, 120 kg, 150 kg, 200 kg, 250 kg). The simulated temperature profiles are compared with real temperature profiles and analyzed. It turns out that the simulated temperature profiles and real temperature profiles are in good agreement. We can use a simulated profile for the optimization of real temperature profile in the case of increasing charge sizes.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.211-214
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• 2007

Solid rocket motor that includes AL powder in propellant gets slag during static firing test. Slag is piled up to weak area in motor case and causes dangerous phenomena like explosion of motor. In this paper, It is shown that boots gap liner casting process was developed and static firing test was performed with better results.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1994.06b
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• pp.35-48
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• 1994

본 연구는 윤활시스템용 오일필터로서 개발된 자성폴리머 필터의 충진밀도에 따른 여과특성을 조사하기 위해 유속, 여과시간 및 자성유무 등의 변수를 변화시키면서 실험실적 방법으로 행해졌으며 다음과 같은 결과는 얻었다. 1. 자성폴리머 필터의 충진밀도가 증가함에 따라 여과효율 및 압력손실은 증가하는 경향을 나타내고 있으며, 이는 자성폴리머 필터의 기공 및 자성에 그 원인이 있다. 2. 자화 및 비자화된 자성폴리머 필터의 압력손실은 동일한 경향을 나타내고 있으나 여과효율은 현저한 차이를 나타내었다. 이는 자성의 영향에 의존함을 알 수 있다. 3. 자성폴리머 필터는 기존의 종이 필터보다 우수한 여과특성을 나타내고 있으며, 이는 다른 여과 메카니즘에 기인한다. 즉 종이 필터는 단지 기공에만 의존하는 표면여과방식인 반면 자성폴리머 필터는 기공(Porosity)과 자력(Magnetic Attration)의 기능을 지닌 심층여과 필터와 자성필터의 두기능을 지니기 때문이다. 따라서 개발된 자성폴리머 필터는 실제 윤활시스템에 적용시 매우 효과적인 오일필터로 작용 할 것으로 사료된다.