• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.483-485
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• 2006

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1999.04a
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• pp.29-29
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• 1999

낙하추 방식의 저에너지 충격시험기는 일정한 질량을 가진 충격체를 금속재/복합재 구조재에 낙하시켜 줌으로써 인위적인 충격에너지를 금속재/복합재 구조재에 가하여 주는 장치로서 금속재/복합재 구조재의 충격으로 인한 손상 거동과 충격특성을 평가하기 위한 용도로 널리 활용되고 있다.

• Journal of radiological science and technology
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• v.35 no.2
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• pp.157-164
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• 2012

The purpose of this study is to analyze the dose distribution when wedge filter is used in the various tissue electron density materials. The dose distribution was assessed that the enhanced dynamic wedge filter and physical wedge filter were used in the solid water phantom, cork phantom, and air cavity. The film dosimetry was suitable simple to measure 2D dose distribution. Therefore, the radiochromic films (Gafchromic EBT2, ISP, NJ, USA) were selected to measure and to analyze the dose distributions. A linear accelerator using 6 MV photon were irradiated to field size of $10{\times}10cm^2$ with 400 MUs. The dose distributions of EBT2 films were analyzed the in-field area and penumbra regions by using dose analysis program. In the dose distributions of wedge field, the dose from a physical wedge was higher than that from a dynamic wedge at the same electron density materials. A dose distributions of wedge type in the solid water phantom and the cork phantom were in agreements with 2%. However, the dose distribution in air cavity showed the large difference with those in the solid water phantom or cork phantom dose distributions. Dose distribution of wedge field in air cavity was not shown the wedge effect. The penumbra width, out of the field of thick and thin, was observed larger from 1 cm to 2 cm at the thick end. The penumbra of physical wedge filter was much larger average 6% than the dynamic wedge filter. If the physical wedge filter is used, the dose was increased to effect the scatter that interacted with photon and physical wedge. In the case of difference in electron like the soft tissue, lung, and air, the transmission, absorption, and scattering were changed in the medium at high energy photon. Therefore, the treatment at the difference electron density should be inhomogeneity correction in treatment planning system.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.244-245
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• 1999

고온 집진을 위한 세라믹 필터의 개발은 1980년대 이후 유럽을 중심으로 활발한 연구가 수행되고 있으며 기존 대기오염 방지 시설로는 처리가 불가능한 고온 공정에 상용화 되어 있고 국내에도 비철금속, 탄화공정, 유리 용해로 등의 공정에 세라믹 필터을 이용한 고온 집진 공정이 설치되어있다. 본 연구에서는 국내에서 개발한 저밀도 세라믹 필터를 이용해 300~$600^{\circ}C$의 고온에서 장시간 실험을 수행 하였으며 장기 집진시 차압과 효율 그리고 세라믹 필터의 특성 변화를 관찰하였다.(중략)

• Korean Journal of Optics and Photonics
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• v.17 no.4
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• pp.371-380
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• 2006

We design and fabricate a novel tunable wavelength filter, which utilizes long-range surface plasmon-polaritons excited along nm-thick-metal strips. A gold metal strip, with $\sim$ cm length, 20 nm thickness, and $\sim$ 5$\mu$m width, is embedded in thick thermo-optic Polymer films supported by a silicon wafer. A dielectric Bragg grating structure is Placed on the metal strip, so that transmission signals at telecom wavelength are selected by thermal effect of the thermo-optic polymer. High extinction ratio of 25 dB and total insertion loss of $\sim$25 dB/cm can be measured by single-mode coupling of optical fibers. We also verify that wavelength tuning of the long-range surface plasmon-polariton filters can be achieved by electric current directly applied to the metal-strip waveguides.

• Membrane Journal
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• v.8 no.4
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• pp.191-202
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• 1998

The emission standards for diesel particulates have been continued to become tighter. This article reviews the pore and how to filtering characteristics and how to design the ceramic honeycomb filter which is generally used for diesel particulate filter. And the properties and fabrication methods of other particulate filters, i.e. ceramic fiber candle filter, ceramic foam filter, ceramic cross-flow filter and metal filter, are presented in this review. The results show that though the various filters have been developed and tested in the field, the more efforts are needed for the commercilaization of the diesel particulate filter.

• Membrane Journal
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• v.17 no.4
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• pp.381-386
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• 2007

Hollow fibers were made using the nickel slurry containing nickel particles and polymers by phase inversion method. And then, metallic filters were fabricated by sintering method at $1,150^{\circ}C$ under reduction condition. Metallic microfiltration membranes were prepared by coating nickel particles on the metallic filter. The properties of the metallic hollow fiber filters and microfiltration membranes such as pore size and strength were investigated. The metallic membrane showed good resistance against acid, base and chlorine. It was observed that the membrane exhibited good recovery rate by back washing.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.151-158
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• 2007

Filtration studies, using simulated test nanoparticles or diesel nanoparticles, have been performed about Inconel foam filters for DPF combined with electrostatic precipitation. The simulated test particles were synthesized by laser ablation in the nitrogen atmosphere at the standard condition. The diesel particles were exhausted from the diesel engine driven on the condition of idle or load mode. Filtration efficiency of the metal foam filter is very low because most of particles are penetrated through the large pores of filter. However, the efficiency was considerably improved by applying the electric field to the filter and/or charging the nanoparticles. Nevertheless, the pressure drop of filter hardly increased because the filter-pores were not clogged by deposited particles and kept open.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.4
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• pp.247-254
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• 2012

Vitrification technology has been widely applied as one of effective processing methods for wastes generated in nuclear power plants. The advantage of vitrifying for low- and intermediate-level radioactive wastes has a large volume reduction and good durability for the final products. Recently, a filter using on HVAC(Heating Ventilating & Air Conditioning System) is composed with media (glass fiber) and separator (aluminum film) has been studied the proper treatment technology for meeting the waste disposal requirement. Present paper is a feasibility study for the filter vitrification that developing of the glass compositions for filter melting and melting test for physicochemical characteristic evaluation. The aluminum metal of film type is preparing with 0.5 cm size for proper mixing with glass frit, glass fiber is also preparing with 1 cm size within crucible. The glass compositions should be developed considering molten glass are related with wastes reduction. Glass compositions obtained from developing on glass formulation are mainly composed of $SiO_2$ and $B_2O_3$ for aluminum metal. A variety of factors obtained from the glass formulation and melting test are reviewed, which is feeding rate and glass characteristics of final products such as durability for implementing the wastes disposal requirement.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.79-82
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• 2000

필터 집진기는 집진효율, 내열, 그리고 내화학성이 우수하기 때문에 고온 정밀집진 또는 부식성 가스의 집진을 위하여 매우 유용한 장치이다. 그러나 세라믹이나 금속 필터를 사용하는 필터 집진기는 운전 시에 필터의 파손에 대한 잠정적인 우려가 있기 때문에 이를 극복하고 시스템의 신빙성을 100% 확보하는 것이 궁극적인 과제로 인식되고 있다. 고온 세라믹 필터의 활용이 가장주목시 되고있는 IGCC 집진의 경우 석탄가스화 및 탈황 과정에서 발생되는 분진을 고온고압에서 제거하여 가스터빈을 보호하는 공정으로써 운전중에 필터가 파손되면 그 부분으로 분진가스가 급격히 빠져나가 큰 분진 입자가 가스터빈으로 유입되고 심한 경우에는 파손된 필터의 파편이 여기에 동반될 수 있다.(중략)