• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.619-622
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• 2009

INCONEL 718합금은 상온, 고온 및 저온환경에서 기계적 특성이 아주 우수하다. 상온에서의 모재 강도는 약 900MPa이며, 열처리 후 시효경화처리에 의해 강도가 약 1300MPa까지 증가한다. 이러한 INCONEL 718합금의 기계적 특성은 시험결과에서도 유사한 값을 나타내었고, GTAW 용접부의 상온 기계적 특성도 모재보다 우수한 강도를 나타내었다. 또한 저온에서의 기계적 특성은 모든 시험조건에서 상온보다 높은 강도를 나타내었으며, 열처리 모재시편과 용접시편은 1400MPa에 달하는 고강도를 나타내었다. 이러한 결과를 바탕으로 INCONEL 718합금의 저온 기계적 특성이 우수한 것을 증명하였고, 용접성 또한 모재의 특성과 같이 상온 및 저온 특성이 우수한 것을 알 수 있었다. INCONEL 718 합금과 STS 316L의 이종접합의 경우에도 $-100^{\circ}C$환경의 인장강도가 상온보다 300MPa 이상 증가하는 것을 알 수 있었다. 따라서, INCONEL 718합금은 $100^{\circ}C$이하부터 일정온도까지는 기계적 특성이 계속 증가 할 것으로 사료되며, 극저온 고압 상태로 공급되는 산화제 배관 제작에 적합한 소재로 판단된다.

• Environmental engineer
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• v.23 s.244
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• pp.2-6
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• 2006

‘환경정책을 입안할 때는 현장에서 직접 관련업에 종사하고 있는 환경기술인들의 의견이 구체적으로 반영되어야 합니다.’ 다년간 환경기술인 생활을 하다가 10여년 전부터 환경산업체인 유한회사 동양 환경 건설의 대표이사직을 맡고 있는 한상온 사장은 현장의 목소리가 정책에 많이 반영 되기를 바라고 있다. 한 사장은 또 현행 양벌 규정에 대해서도 다소 불합리하다고 강조했다. 본지는 지난 23일 연합회 회의실에서 한상온 사장을 만나 그의 환경관을 들어봤다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.2 no.2
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• pp.65-71
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• 2001

Recently the quantities of waste asphalt concrete at construction sites have increased greatly, but the maintenance and final disposal is very difficult problem. Therefore, we were faced with a worsening environmental problem brought about illegal measures. One of the most effective recycling method is cold recycling. This method will satisfy treatment and recycling of construction wastes. Also it is very important question in the preservation of environmental and natural resources. So, in this paper, we dealt cold recycling modified asphalt mixtures using emulsified asphalt to concern the effect of adding reclaimed asphalt concrete 30, 40, 50% and using SBR Latex for modified asphalt mixtures.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1011-1015
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• 2017

In this study, numerical and experimental studies on the nozzle flow in a sub-scale cold flow test were conducted to simulate high altitude condition. In the theoretical calculation, the temperature of the nozzle outlet is calculated to be lower than the liquefaction point, and the fluid exists at the phase change point. Also, numerical analysis result is higher than theory calculation but lower than liquefaction temperature. As a result of cold flow test, it was confirmed that the temperature was much higher than theory and analysis. This is because it assumed that it is adiabatic in the theoretical calculation, but the experiment in the actual environment is not the adiabatic but the heat exchange with the outside exists.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.23-26
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• 2007

A preliminary， study of low temperature condition was performed to simulate high altitude condition. The mixed air temperature were investigated at various condition by experiments using cryogenic air by heat exchanger and normal temperature air. An experimental setup was constructed to simulate low temperature condition with liquid nitrogen. To control mass flow rate, orifice and pressure regulators were used. The experimental results show that the mixed air temperature increases linearly with mass flow rate of normal temperature air. Therefore it can be help to simulate a low temperature condition of high altitude.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.23-30
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• 2006

Emulsified Asphalt Mixture(EAM) is more environmentally-friendly and cost-effective than typical Hot Mix Asphalt (HMA) because EAM does not produce carcinogenic substances, e.g., naphtha, kerosene, during the both of manufacturing and roadway construction process. Also, it does not require heating the aggregates and asphalt binder. However, EAM has some disadvantages. Generally EAM has a less load bearing capacity and more moisture susceptibility than conventional HMA. The study evaluated a Fiber modified EAM (FEAM) to increase load bearing capacity and to decrease moisture susceptibility of EAM. Modified Marshall mix design was developed to find Optimum Emulsion Contents (OEC), Optimum Water Contents (OWC), and Optimum Fiber Contents (OFC). A series of test were performed on the fabricated specimen with OBC, OWC, and OFC. Tests include Marshall Stability, Indirect Tensile Strength, and Resilient modulus test. Comparison analyses were performed among EAM, Fiber modified EAM (FEAM), and typical HMA to verify the applicability of EAM and FEAM in the field. Test results indicated that both of EAM and FEAM have an enough capability to resist medium traffic volume based on the Marshall mix design criteria. Also the study found that fiber modification is effective to increase the load bearing capacity and moisture damage resistance of EAM.

• Prospectives of Industrial Chemistry
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• v.19 no.5
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• pp.1-11
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• 2016

우리나라는 1970년대를 기점으로 하여 급격한 경제성장과 산업기술의 발전이 이루어졌다. 경제성장과 함께 주택의 보급 또한 급격하게 증가하게 되었고, 주택의 보급을 위한 건축자재 및 생활용품의 개발이 급속도로 이루어졌다. 이에 따라 실내에서 사용하는 기구 및 건축재료가 매우 다양해졌으며, 이로 인한 새로운 오염물질의 배출이 급격히 증가하게 되었다. 최근 새로운 기술로 소개되고 있는 촉매 산화법의 경우 제거하려는 대상 실내대기오염물질을 촉매를 이용하여 CO₂나 H₂O 등으로 산화시켜 제거하는 방법이며, 최근 많은 연구가 활발하게 수행되고 있다. 촉매를 이용하는 촉매 산화법은 광촉매 산화법과, 촉매의 성능만을 이용하여 대상물질을 산화하는 촉매산화법으로 구분된다. 광촉매 산화법은 특정 파장에서 반응하는 촉매에 자외선을 조사하여 실내오염물질을 산화제거하는 방법으로, 산화성능이 우수하여 여러 가지 실내오염가스에 적용되고 있으나, 별도의 광원이 필요하며, 포름알데히드 산화 시 CO₂와 H₂O 이외에도 dichloroacetyl chloride (C₂HCl₃O), trichloroethylene (C₂HCl₃), phosgene (COCl₂) 등과 같은 부수적인 2차 유해물질이 발생함에 따라 이를 처리하기 위한 대책이 수반되어야 한다. 반면, 촉매 산화법의 경우 별도의 광원이나 에너지원 없이, 촉매를 이용하여 대기오염물질을 인체에 무해한 물질로 완전 산화시키는 방법으로써, 최근 많은 연구가 수행되어 상온에서 구동 가능한 촉매가 개발되었고, 이의 연구가 활발히 이루어지고 있다. 이에 상온산화촉매기술의 연구동향 및 사례를 확인하고, 향후 상온산화촉매기술이 나아가야 할 방향을 제시하고자 한다. 본 연구는 환경부 환경산업선진화기술개발사업의 지원을 받아 수행되었습니다(2016000140004).

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.2
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• pp.119-128
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• 2010

The hygrothermal effect on the strength of composite single-lap bonded joints were investigated. The specimens were manufactured in four different manufacturing methods and tested in three different environmental conditions. An interesting result is that the strengths of the joints in the elevated temperature and wet (ETW) conditions were found to be 11 ~ 23% higher than those in the room temperature and dry (RTD) environment. In contrast, the strengths of the joints in the cold temperature and dry (CTD) condition decrease by 8 ~ 21% compared to those in the RTD environment except for cobonded joint. The difference in the strength by testing environments is mainly attributed to the change of the material properties of adhesive by temperature and moisture.

• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.657-662
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• 2018

In this study, the effect of $Pt/TiO_2$ catalysts on the CO oxidation reaction at room temperature was investigated using various $TiO_2$ supports with different physical properties to compare and evaluate $Pt/TiO_2$ catalysts. Physicochemical properties of the catalyst were alanyzed using XPS, CO-chemisorption, BET, and CO-TPD. As a result, when the active particle diameter was smaller, while the metal dispersion and surface area were larger, the CO room temperature oxidation reaction was better. These physical properties increased the number of active sites, causing the target material to increase the adsorption amount of CO. In addition, when the $O_2$-consumption increased, the CO-room temperature oxidation reaction activity increased due to the excellent oxygen-transferring ability.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.218-222
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• 2005