• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.114-116
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• 2008

Head-space method를 이용하여 살충제에 대한 VOCs의 배출특성을 평가한 결과 모든 제품에서 다양한 VOCs가 검출되었으며, 제품에 따라 다소 차이는 있지만 대부분의 생활용품에서 유해한 오염물질이 검출되었다. 국내 제조회사나, 동일제품의 종류, 제품의 형태에 따라 VOCs의 종류가 유사한 것도 있지만, 대부분 배출특성의 차이가 있을 수 있다고 사료되어진다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.309-310
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• 2001

휘발성 유기화합물(Volatile Organic Compounds; 이하 VOCs라 함)은 도시대기 중 광화학 스모그의 기인자인 동시에 발암성 혹은 돌연변이원성인 인체에 유해한 물질들이 많으므로 최근 들어 관심의 대상이 되고 있다. 이러한 VOCs의 발생원은 복잡ㆍ다양하지만 인위적인 주요 배출원은 유기용제와 자동차이다. 본 연구에서는 자동차 배출가스의 영향을 많이 밭고 있는 도시교통밀집지역의 VOCs의 출현양상 및 분포특성을 파악하고 도시교통밀집지역과 교통량의 영향을 비교적 적게 받는 교외 지역에서의 VOCs 분포특성을 비교해 보고자 한다. (중략)

• Journal of the Korean housing association
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• v.19 no.1
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• pp.49-55
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• 2008

Recently, much attention has been paid to the problem such as sick building syndrome, which caused by the indoor air pollutant. Volatile Organic Compounds $(VOC_s)$ and formaldehyde have been considered as one of the main reason that causes indoor air pollutant. This study is for introducing and designing thermal performance of super energy saving building by conducting $VOC_s$ and formaldehyde concentration in the 3Liter house. The results of the measurement for 10 months showed that $VOC_s$ and formaldehyde decreased until the guideline concentration. It took about 7 months, and it appeared right after new construction. However, their levels were showed higher concentration in comparison with the ordinary residential houses (apartment house). The main difference of between newly built 3Liter house and ordinary apartment is their air changes, which are 0.67/h for 3Liter house and 4.0/h for the apartment.

• Elastomers and Composites
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• v.48 no.3
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• pp.209-215
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• 2013

On this study, visible-light responsive photocatalyst prepared by sol-gel method was evaluated the effect of the reduction of volatile organic compounds (VOCs) occurred in vehicle interior and its property was examined. According to UV/visible result, visible-light responsive photocatalyst was found that the UV-visible peak is red shift at 420nm, is sensitive in the visible light region. With vehicle interior parts and materials coated visible-light responsive photocatalyst, VOCs was measured by GC/MS. Measuring the VOCs generated from vehicle interior parts and materials, the reduction of VOCs was confirmed.

• Membrane Journal
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• v.11 no.2
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• pp.74-82
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• 2001

By using a phenomenological approach, model equations incorporating the resistance-in¬series concept were established to evaluate quantitatively concentration polarization in the boundary layer in feed adjacent to the membrane surface in the vapor permeation and separation of volatile organic compounds (VOCS)/$N_2$ mixture through po]y(dimethylsiloxane) (PDMS) membrane. The vapor permeations of various VOCS/$N_2$ mixtures through PDMS membrane were carried out at various feed flow rates. Chlorinated hydrocarbons, such as, methylene chloride, chlorofonn, 1,2-clichloroethane and 1,1,2-trichloroethane were used as organic vapor. By fitting the model equations to the experimental penneation data. the model parameters were detennined. respectively. Both the mass transfer coefficient of VOC across tbe boundary layer and concentration polarization modulus as a measure of the extent of concentration polarization were eitimated Quantitatively by the mooe1 equations with the determined model parameters. From the analysis on the detennined model parameters, the boundary layer resistance due to the concentration polarization of VOCs component was found to be more significant when the condensability of voe was greater. This study seeks to emphasize the importance of the boundary resistance on the vapor penneation of the vapor/gas mixtures with high permeability and high selectivity towards the minor component VOC.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.308-309
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• 2016

Reducing surface recombination is a critical factor for high efficiency silicon solar cells. The passivation process is for reducing dangling bonds which are carrier. Tunnel oxide layer is one of main issues to achieve a good passivation between silicon wafer and emitter layer. Many research use wet-chemical oxidation or thermally grown which the highest conversion efficiencies have been reported so far. In this study, we deposit ultra-thin tunnel oxide layer by PECVD (Plasma Enhanced Chemical Vapor Deposition) using $N_2O$ plasma. Both side deposit tunnel oxide layer in different RF-power and phosphorus doped a-Si:H layer. After deposit, samples are annealed at $850^{\circ}C$ for 1 hour in $N_2$ gas atmosphere. After annealing, samples are measured lifetime and implied Voc (iVoc) by QSSPC (Quasi-Steady-State Photo Conductance). After measure, samples are annealed at $400^{\circ}C$ for 30 minute in $Ar/H_2$ gas atmosphere and then measure again lifetime and implied VOC. The lifetime is increase after all process also implied VOC. The highest results are lifetime $762{\mu}s$, implied Voc 733 mV at RF-power 200 W. The results of C-V measurement shows that Dit is increase when RF-power increase. Using this optimized tunnel oxide layer is attributed to increase iVoc. As a consequence, the cell efficiency is increased such as tunnel mechanism based solar cell application.

• International Journal of Highway Engineering
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• v.12 no.1
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• pp.55-59
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• 2010

High VOC(Vehicle Operating Cost) is the main reason for the rehabilitation of paved road and VOC is composed of fuel consumption, lubricant oil consumption, parts consumption, etc. Fuel consumption is one of the largest components of VOC and the roughness of road represents the deterioration level of the road. For these reasons, the fuel consumption is measured for different IRI(International Roughness Index) in this study. The fuel consumption was measured by processing the voltage signal of fuel injector of vehicle and the speed was measured with GPS. The change rate of fuel consumption for different IRI can be calculated with the results of this test. It's concluded that fuel consumption(L/100km) of medium and large passenger car increases 7 times fast of the increase of IRI(m/km) around 3.5m/km in the speed range of 40 ~ 100km/h, and fuel consumption is the best at 60km/h.

• Journal of Soil and Groundwater Environment
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• v.12 no.6
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• pp.60-69
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• 2007

Understanding the behavior of gas phase VOCs (volatile organic compounds) in unsaturated soils is of a great environmental importance for public health concerns. Moment analysis for the breakthrough curves (BTCs) during transport of chemicals in porous media was known to be a useful tool to evaluate the velocity, spreadness, and the skewness of the plume of the chemicals. In this study, the temporal moments of the BTCs of a group of VOCs were analyzed for the gaseous transport in an unsaturated soil. BTCs were measured using lab-scale column experiments for four different VOCs at the water saturation range of 0.04-0.46, and for eleven VOCs at a water saturation of 0.21. The central second and third moments of the VOCs were compared with the water saturation and the first moment. It was found that both central second and third moments increased with the first moment. The central third moment was, however, found to be more sensitive to the first moment.

• Journal of Adhesion and Interface
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• v.11 no.1
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• pp.9-14
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• 2010

O/W emulsions were prepared with the phase inversion emulsification methods. The emulsifiers were used the UNIQ-1 (isopropylamine alkyl aryl sulphonate) and UNIQ-2 (alkoxylated glycol ether). Investigated effect that HLB value, agitator velocity and manufacture temperature get in mean particle size of emulsions. Mean particle size receives much effect of HLB value. Also, estimated stability about storage temperature and light. Emulsion's mean particle size was 193 nm lastly, reduced VOC amount used 90% than existing alkyd resin.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.31-37
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• 2021

In this paper proposed a feature fusion and spatial attention-based modified YOLOv4S for small and occluded detection. Conventional YOLOv4S is a lightweight network and lacks feature extraction capability compared to the method of the deep network. The proposed method first combines feature maps of different scales with feature fusion to enhance semantic and low-level information. In addition expanding the receptive field with dilated convolution, the detection accuracy for small and occluded objects was improved. Second by improving the conventional spatial information with spatial attention, the detection accuracy of objects classified and occluded between objects was improved. PASCAL VOC and COCO datasets were used for quantitative evaluation of the proposed method. The proposed method improved mAP by 2.7% in the PASCAL VOC dataset and 1.8% in the COCO dataset compared to the Conventional YOLOv4S.