• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.384-388
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• 2000

일반적으로 흡착분리공정 기술개발은 대략 3단계의 과정을 거치게 되는데 흡착제의 선정, 흡착탑의 거동해석, 연속공정 구성 및 운전으로 이루어진다. 이중 흡착제의 선정은 대상 혼합물에 어떤 흡착제를 사용하여 효율적인 분리 결과를 얻을 수 있는가를 결정하는 기초단계이면서도 가장 중요한 과정이다. 이를 위해 여러 흡착제에 대한 흡착평형량과 이로부터 얻어지는 선택도, 흡착열, 그리고 흡착질과 흡착제 사이의 물질전달저항과 흡착제의 기공 분포도, 기공부피, 기공율, 비표면적, 충전 밀도(Bulk Density), 파쇄 강도 및 마모저항 등과 같은 물리적 특성을 종합적으로 비교 검토하여 흡착제를 선택하여야 한다. (중략)

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.94-94
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• 2011

LCD, PDP, OLED 등으로 대표되는 FPD 장치의 투명전극으로 사용되는 ITO의 전기 광학적 특성을 연구하였다. 향후 발전시켜나갈 Flexible display 에서는 ITO를 저온에서 증착해야 할 필요성이 대두되었고, 이에 따라 기판의 온도를 상온으로 유지하면서 고품질의 ITO 박막을 제조하고자 하는 연구가 진행되고 있다. 본 연구에서는 상온 조건에서 유리 기판 위에 RF Magnetron Sputtering 장치를 이용하여 ITO 박막을 증착하였으며 다양한 Magnetic구조를 통한 자장의 분포를 제어하였다. Magnetic을 이용시 RT에서 얻은 면저항보다 낮은 면저항을 가질 수 있을 뿐만 아니라 온도 증가($250^{\circ}C$)에 따른 결과와 비교시 차이가 거의 없음을 알 수 있었다.

• Geophysics and Geophysical Exploration
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• v.16 no.3
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• pp.154-162
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• 2013

Vertical electrical sounding and 2D electrical resistivity survey were applied for evaluating the characteristics of alluvial layers at a groundwater artificial recharge site. The fine particles in alluvial layer, main target layer of groundwater artificial recharge, may cause clogging phenomena. In this case, electrical resistivity method is an effective technique to verify the spatial distribution of low-resistivity layers, such as saturated silts and clays. On the other hand, much attention should be paid to interpret the resistivity data in unconsolidated layers, because thick clayey overburden sometimes produces a masking effect on underlying interbedded resistive sands and gravels. Considering these points, we designed 35 points arranged in a grid form for vertical electrical sounding and 10 lines for 2D electrical resistivity survey, and concentrated our effort on enhancing the vertical and horizontal resolution of resistivity images. According to the results, 15 meters thick layers consisting of sands and gravels are located in 30 meters below ground. And the spatial distribution of silts and clays are mapped, which may cause clogging. Consequently, this approach can contribute to design and determine the location and depth of injection and observation wells for groundwater artificial recharge.

• Journal of the Korean Geosynthetics Society
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• v.10 no.4
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• pp.113-121
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• 2011

River sand has generally used for the backfill material of underground power cables. The thermal resistivity of it has $150^{\circ}C$-cm/Watt in wet condition and more than double in dry condition. The final goal of this study is to find the backfill material which has a small change in thermal resistivity with various water contents, for example thermal resistivity is $50^{\circ}C$-cm/Watt and $100^{\circ}C$-cm/Watt in wet and dry conditions respectively. In this study it is presented that the comparison of thermal resistivity using stone powder, crush rock, weathered granite soil and Jumunjin sand as well as river sand in the needle method regarding water content, dry unit weight and particle size distribution. As a result, the thermal resistivity of a material is minimized when they have maximum dry unit weight at optimum moisture content and maximum density by appropriately mixing materials for particle size distribution. Therefore thermal resistivity characteristics should be considered two factors: one is the difference between natural dry condition and dry state after optimum moisture content, and the other is the difference between unit weight of raw material and maximum dry density.

• Journal of the Korean Vacuum Society
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• v.16 no.6
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• pp.439-445
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• 2007

SiGe integrated circuits are being used in the field of high-speed wire/wireless communications and microwave systems due to the RF/high-speed analog characteristics and the easiness in the fabrication. Reducing the resistance variation in SiGe thin film resistors results in enhancing the reliability of integrated circuits. In this paper, we investigate the causes that generate the resistance nonuniformity after the silicon-based thin film resistor was fabricated, and consider the counter plan against that. Because the Ti-B precipitate, which formed during the silicide process of the SiGe thin film resistor, gives rise to the nonuniformity of SiGe resistors, the boron ions should be implanted as many as possible. In addition, the resistance deviation increases as the size of the contact hole that interconnects the SiGe resistor and the metal line decreases. Therefore, the size of the contact hole must be enlarged in order to reduce the resistance deviation.

• Journal of the Korean Geophysical Society
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• v.9 no.4
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• pp.455-462
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• 2006

In this paper, we used the electrical resistivity survey as a simple and reasonable technique to evaluate the effectiveness of grouting. And, a mechanism was also analyzed to understand how the electrical resistivity is affected by the loss of fine material in the core of a dam. From this mechanism, it was confirmed that electrical resistivity value of the damage section may be up or down depending on the survey conditions. This result seems to be contrary to the previous study that electrical resistivity of the damage zone become alway low. To clarify what was investigated, the electrical resistivity before and after grouting was compared and analyzed. As the result, it was concluded that grouting effectiveness was successfully assessed by electrical resistivity survey.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.143-147
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• 2001

Nineteen pepper (Capsicum annuum L.) cultivars were screened for the resistance to two common species of root-knot nematodes, Meloidogyne incognita and M. arenaria. The tested pepper cultivars showed different degrees of resistance to M. incognita but all were resistant to M. arenaria. The cultivars cv. Gonggongchil, Green No. 500 Pimento, Dahonggeon, Manitta, Shinbaram, Perfecto, and Hanmaeum were resistant to the both species of root-knot nematodes. Therefore, seven selected resistant pepper cultivars are recommended as resistant rotation crops in greenhouses where root-knot nematodes are problematic.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.93-98
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• 2009

Comprehension of physical properties distribution of underground cavity must be made primarily to show the clear image of the state of the cavity. A physical scale model experiment is executed assuming that underground cavity in filled with air or water of different ratio. The state of cavity wall is considered wet. Cavity model is made of agar. As a experimental result, even if the cavity wall is wet, high air and water ratio cavity shows high anomaly.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.235-235
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• 2018

홍수 시의 산지하천 만곡부는 2차류 발생과 편수위 상승에 따른 하상세굴 및 홍수범람 위험이 크다. 만곡부 외측에 주로 설치되어 있는 콘크리트 옹벽호안은 표면이 매끄러워 홍수피해를 가중 시킨다. 이러한 피해를 저감시키기 위해 콘크리트 옹벽에 돌출줄눈을 설치하여 유속조감 및 설치효과를 분석한 바 있다. 본 연구에서는 기존에 제안된 직사각형 단면의 돌출줄눈보다 내구성을 추구한 사다리꼴 단면의 돌출줄눈을 제시하여 수리모형 실험을 수행하였다. 수리모형 실험은 개수로 직선수로에서 수로경사 0.0035 조건에서 수로 출구 게이트를 조절하면서 이루어졌다. 모형 돌출줄눈의 조도높이는 3cm로 하였으며, 사다리꼴 밑각은 $45^{\circ}$로 완만한 경우이다. 설치간격은 무차원 돌출줄눈 간격을 기준으로 ?형 조도인 6으로 하였다. 돌출줄눈의 설치 유무에 따라 유량에 따른 수위를 측정하고 유속을 산정하여, 마찰저항의 변화를 파악하였다. 공급유량에 따른 Froude 수는 0.168~0.359 범위였으며, 유량이 증가에 따라 Manning의 조도계수는 감소하였다. Froude 수가 0.25보다 큰 경우 돌출줄눈설치의 조도계수가 미설치보다 큰 것으로 파악되었다. 그러나 사다리꼴 돌출줄눈의 흐름저항효과는 직사각형 돌출줄눈에 비해 상대적으로 작았다. 수로 횡단면의 수위분포에 따르면, 돌출줄눈 설치 측벽 주변에서 흐름저항에 따른 유속감소와 수위상승 효과가 나타나는 것으로 파악되었다. 이번 사다리꼴 돌출줄눈은 흐름저항 효과가 크지 않았기 때문에 사다리꼴 밑각을 조정하여 새로운 단면에 대한 추가적인 실험이 필요할 것으로 보인다.

• 한국전기화학회:학술대회논문집
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• 2002.10a
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• pp.54-54
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• 2002