• Korean Journal of Optics and Photonics
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• v.28 no.1
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• pp.28-32
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• 2017

In this research, we designed an LSPR sensor based on a thin-film multilayer comprising $TiO_2$ and $SiO_2$. The thickness of the overall substrate layer of the suggested multilayer LSPR sensor is limited to 100 nm, and the number of repeating $TiO_2$ and $SiO_2$ thin films is 1-4 within a limited thickness. Additionally, a nanowire structure with a gold thin film of 40 nm, height of 40 nm, period of 600 nm, and line width of 300 nm was formed on the multilayer. To design the variable wavelength-type SPR, the angle was fixed at $75^{\circ}$ and the wavelength was changed. We then simulated the system with the finite-element method (FEM) using Maxwell's equations. It was confirmed that the resonance wavelength became shorter as the number of multilayers increased when the refractive index was fixed. We found that the wavelength changes were more sensitive. However, no changes were observed when the number of the multilayers was three or higher.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.527-532
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• 2016

The effects of gas velocity and solid circulation rate on the axial solid holdup distribution have been determined in a 10 mm-I.D. ${\times}$ 800 mm-high circulating fluidized bed plasma reactor under reduced pressure (1torr). Polystyrene polymer powder and nitrogen gas are used as solid and gas materials respectively. The change of solid circulation rate by a large gas flow rate of the riser (40~80 sccm) is also possible by a relatively small gas flow rate of the solid recirculation part (6.6~9.9 sccm). The solid circulation rate in the reactor under reduced pressure increases with increasing aeration velocity in the solid recirculation part. The axial solid holdup in the riser decreases from the dense at the bottom to the dilute phase at the top section of the riser. Solid holdups at the axial positions in the riser increase linearly with increasing solid circulating velocity. From these results, we could determine the position of plasma load for good plasma ignition, maintain and plasma reaction.

• Journal of the Korean Geotechnical Society
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• v.24 no.5
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• pp.99-106
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• 2008

This study is concernsed with the effect of a chimney drainage system installed at the back of reinforced soil block on preventing the pore water pressure development. A series of finite-element analyses based on transient seepage analysis were performed for a number of cases with different patterns of the chimney drainage system. The results were thoroughly analyzed to get insight into the mechanism of pore water pressure reduction effect of the chimney drainage system. It is shown that a vertical drainage system installed at the back of reinforced zone can be an effective means of maintaining the wall stability during rainfall by preventing pore pressure increase in the reinforced as well as the backfill zones. Also shown is that the optimum height of the chimney drain is 50% of the wall height. Practical implications of the findings were discussed.

• 월간 기계설비
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• s.298
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• pp.56-65
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• 2015

1970년대 고급 아파트촌의 대명사로 불리웠던 동부이촌동이 강북지역 한강변 초고층 주거시설의 랜드마크로 또한번 새롭게 변신한다. 지상 56층, 42층, 36층 총 3개동으로 구성된 초고층 주거시설이 오는 8월 1일부터 입주할 예정이기 때문이다. 이 아파트는 당분간 건립되기 힘든, 강북에서 가장 높은 초고층 주거시설로 지난 2013년 4월 서울시가 한강변 건축물 높이를 35층으로 제한하기 전인 2009년 사업시행 인가를 받았다. 한강이 내려다 보이고 인근에 국립중앙박물관, 용산가족공원, 한강공원 등 대형 공원이 있는데다 강남권, 강북권, 강서권으로의 접근성이 뛰어나 한강변의 새로운 랜드마크로 주목받고 있는 만큼 특화된 커뮤니티 시설과 함께 친환경 건축물 최우수 등급, 에너지효율 1등급, 초고속 정보통신 특등급 인증 획득을 목표로 최고의 주거성능등급 아파트 시공에 만전을 기하고 있다. 본지는 준공준비에 여념이 없는 이촌동 렉스아파트 재건축 현장에서 삼성물산 권진학 현장소장과 (주)우진아이엔에스(대표 홍평우 손광근) 김동원 현장소장을 만났다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.149-154
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• 2010

건축기술의 눈부신 발전과 경제적 가치추구 등에 따른 국가 사회적 수요로 인하여 초고층 건축물의 건설물량은 이들 건축물에 대한 효과적인 피난안전대책을 정립하기도 전에 급속히 증가하는 추세이다. 우리나라는 2009년 7월 16일 재정된 건축법 시행령을 통하여 층수가 50층 이상이거나 높이가 200미터 이상인 건축물을 '초고층 건축물'로 규정하고, 이러한 건축물의 피난안전을 위하여 지상층으로부터 최대 30개 층마다 설치하는 대피공간을 '피난안전구역'으로 정의하였다. 이후 2010년 2월 18일 개정령에서는 초고층 건축물의 피난안전구역을 건축물의 '피난층'으로 인정하기에 이르렀다. 그러나 피난대상인원 등에 따른 대피공간의 면적이나 구조 등 내부시설에 대한 설치기준이 없어 피난안전구역으로서의 충분한 신뢰성을 확보하지 못하고 있어 이에 대한 심층적 연구와 기준의 개선이 필요한 실정이다.

• The Science & Technology
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• v.35 no.6 s.397
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• pp.28-29
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• 2002

작년 7월에 문을 연 일본과학미래관은 21세기 첨단 과학기술의 발전과 미래사회에서의 과학기술을 체험할 수 있는 최신 과학관이다. 7층 높이의 현대식 건물에 4개층으로 이루어진 전시관 1층에는 '지구환경과 미개척의 세계'등을 비롯하여 특별전시실이 있으며 에스컬레이트를 이용하여 3층에 올라가면 '기술혁신과 미래', '정보과학과 기술'의 전시물들을 만나게 된다.

• Journal of the Korean Solar Energy Society
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• v.26 no.3
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• pp.17-24
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• 2006

최근에 에너지절약 차원에서 종래의 공조방식을 대신할 새로운 냉난방시스템 개발이 요구되고 있는데, 본 논문에서는 태양열 집열기를 이용하는 데시컨트 시스템 중 제습역할을 실질적으로 담당하는 제습기의 충진층 부분에서의 열 및 물질전달에 관한 일련의 해석 결과를 발표하고 있다. 제습과정에서 액체흡수제는 충진층에서 열 뿐만 아니라 물질전달을 수반하게 되는데, 이 결과 건물에 냉방 및 난방효과를 가져다 준다. 따라서 이 충진층의 최적 설계가시스템의 효율을 극대화하기 위해서는 무엇보다도 중요한데, 이를 위해서는 충진층에서의 열 및 물질전달 양상을 규명하여야 한다. 따라서 금번 실험에서는 공기와 액체흡수제와의 접촉면적을 넓히기 위해서 충진재로써 3cm(직경) ${\times}$ 3cm(높이)인 시판중인 플라스틱 재질을 사용하고, 실질적으로 40cm(너비)${\sim}$40cm(깊이)${\times}$40cm(높이)의 충진층을 직접 제작하여 실험을 행하였다. 그 결과, 공기측 열 및 물질전달 계수는 공기 온도와 밀접한 관계를 갖고 있으며, 또한 물질전달계수는 열전달계수와 같은 경향을 보이고 있음을 알 수 있었다.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1057-1062
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• 2008

To overcome disadvantages of conventional two interconnected fluidized beds system, a novel two-interconnected fluidized bed process has been adopted to 3kW chemical-looping combustor. This system has two bubbling beds, solid injection nozzles, solid conveying lines, and downcomers. In this study, effects of operating variables such as gas velocity through the solid injection nozzle, fluidizing velocity, solid height, geometry of solid intake hole, bed temperature on solid circulation rate have been investigated in a 3kW chemical-looping combustor. The solid circulation rate increased as the solid height and the opening area of solid intake holes increased. The effect of the fluidizing velocity and the bed temperature were negligible. Moreover, long-term operation of continuous solid circulation up to 50 hours has been performed to check feasibility of stable operation. The pressure drop profiles in the bubbling beds and the downcomers were maintained steadily and solid circulation was smooth and stable.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.4
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• pp.299-305
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• 2017

Re-engineering is gaining attention due to severe environmental pollution and economic crisis. Although re-engineering in shipbuilding has been carried out steadily, technological advancements, domestic ship repair and maintenance industries are not as prevalent as shipbuilding industries. In order to solve this problems, laser cladding can significantly aid with technical development. Laser cladding produces an outstanding clad layer with minimal dilution and little porosity. In this study, prior to applying laser cladding to an exhaust valve face, the effects of various parameters that affect the characteristics of the 1 pass clad layer were investigated. When laser power was increased, the clad layer width became broader and the height was decreased. In addition, it was identified that the hardness of the clad layer was inversely proportional to the power, and the entire clad layer was diluted through an EDS chemical composition analysis.

• Clean Technology
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• v.10 no.1
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• pp.1-7
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• 2004

In this study, the performance of Aluminium foil etching waste(PWF100) as a cohesive agent was estimated and the methods to commercialize it were investigated through comparison of physical properties between Aluminium foil etching waste(PWF100) and commercial cohesive agent(PAC17). The height of sediment bed was measured according ot the change of the concentration of BKN-100, BKR-110, and BKR-120 prepared by using PWF100. When the concentrations of BKN-100, BKR-110, and BKR-120 were increased, the heights of sediment bed were constant after decreased. Also, the density of sediment bed was investigated according to the change of the concentration of BKN-100. When the concentrations of BKN-100 were increased, the densities of sediment bed were decreased. In addition, based on the concentration of BKN-100, BKR-110, and BKR-120, the sediment rate was experimented. When the concentrations of BKN-100, BKR-110, and BKR-120 were increased, sediment rates were rapid and then slow. Moreover, the volumes of sediment bed were measured according to the change of the concentration of BKN-100. According to increasing the concentrations of BKN-100, the required time for getting to the minimum volume of sedment bed were reduced and then increased. Lastly, the required time for sedimentation based on the concentration of BKN-100, BKR-110, and BKR-120 was investigated. When the concentrations of BKN-100, BKR-110, and BKR-120 were increased, the required times for sedimentation were increased after decreased. From these results, it can be concluded that the PWF100 acts as a cohesive agent.