• Air Cleaning Technology
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• v.20 no.2 s.77
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• pp.1-8
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• 2007

• Air Cleaning Technology
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• v.33 no.4
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• pp.1-8
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• 2020

• Elastomers and Composites
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• v.48 no.3
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• pp.181-189
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• 2013

Unfilled, carbon black-filled, and silica-filled natural rubber (NR) composites were aged with a circular deformation at $60-90^{\circ}C$ and the recovery behaviors were investigated. The samples were aged under the altering aging medium systems of air and distilled water every day for 10 days. The order of the recoveries according to the filler systems was unfilled > silica > carbon black. The recoveries of the samples aged in the air to water altering system were greater than those of the samples aged in the water to air altering system. The initial aging medium dominantly influenced the deformation level.

• Water for future
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• v.28 no.1
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• pp.7-15
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• 1995

• Water for future
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• v.53 no.6
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• pp.86-90
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• 2020

• Proceedings of the Korea Contents Association Conference
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• 2010.05a
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• pp.319-321
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• 2010

수리학에서 다루는 유체 현상은 물과 공기의 경계면인 자유수면을 포함할 때가 많다. 수표면의 곡률이 작은 경우에는 정수압 가정이 적절하지만, 그렇지 않은 경우에는 비정수압 분포를 고려하여야 한다. 이와 같은 문제에서는 수심적분된 천수방정식이 아닌, 네비어-스토크스 방정식(Navier-Stokes equations)에 의존해야 할 때가 많다. 특성이 다른 두 유체, 예를 들면, 물과 공기, 물과 기름과 같이 섞이지 않는 두 유체의 모의를 위하여 본 연구에서는 레블? 기법을 적용하였다. 고전적인 문제인 댐파괴 문제에 적용하여 이를 실험결과, 기존 수치모델링 결과와 비교하여 이의 효율성을 확인하였다.

• Proceedings of the KAIS Fall Conference
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• 2008.05a
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• pp.299-301
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• 2008

본 논문은 세정용 노즐의 기하학적인 형상을 변화시킴으로써 물과 공기를 이용한 비데용 분사노즐의 세정효과를 극대화하기 위한 연구이다. 세정효과와 절수를 목적으로 과거 물만을 공급되었던 비데노즐에 공기를 물을 혼합한 혼합류를 주입하면서 형성되는 노즐 내부 유동현상을 상용코드인 CFD-ACE+을 이용하여 가시화하고자 했다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.599-604
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• 2008

An experimental study has been performed to investigate the air-side capacity and pressure drop of the fin-tube heat exchanger for a fan coil unit under a cooling condition. The experimental data of five kinds of slit fin-tube heat exchangers were measured using an air-enthalpy calorimeter and a constant temperature water bath. Cooling capacities at the air and water rating flow rates were larger at the lower inlet water temperature. With increasing the water flow rate, the cooling capacity increased at the constant rate. Under the lower inlet water temperature, since the condensate was generated more on the fin-tube surface, the air-side pressure drop of the heat exchanger was larger.

• Resources Recycling
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• v.26 no.1
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• pp.22-29
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• 2017

When the ambient air pressure was $0.1kg/cm^2$, there were few spherically formed droplets, which showed very badly fragmented state. The average particle size of the particles constituting the droplet was about 40 nm. When the air pressure increased to $0.5kg/cm^2$, the ratio of the spherical droplet forms increased, but still showed a state of severe disruption. The average particle size of the particles was reduced to about 35 nm. As the air pressure increased to $3kg/cm^2$, the ratio of spherical droplet form significantly increased, the degree of fragmentation even further decreased and the average particle size decreased to 30 nm. When the air pressure increased from 0.1 to $1kg/cm^2$, the XRD peak intensity showed little change, but the specific surface area was decreased. As the air pressure increased to $3kg/cm^2$, the intensity of XRD peaks showed a little decrease, while the specific surface area increased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.4
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• pp.263-273
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• 2016

The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing $NO_x$ emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between $0^{\circ}$ and $90^{\circ}$, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and $NO_x$ emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.