• 복합신소재구조학회 논문집
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• 제6권4호
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• pp.30-37
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• 2015

iFLASH System is new structural floor system which consists of sandwich panels filled with nano-composite. The nano-composite has low specific gravity and high bonding strength with steel plates. The bonding strength is one of important factors for structural performance of iFLASH System and it can further be improved by surface preparation such as blast metal cleaning. However, using none blast steel plates is recommended since surface preparation generates additional fabrication time and cost. In this study, a bonding strength test and bending experiment were conducted to check feasibility of applying none blast steel plates to iFLASH System. Moreover, stress in bonding plane between steel plates and nano-composite was analytically evaluated by finite element method. Consequently, flexural capacity of the specimen was 11% higher than theoretically calibrated value and its flexural behavior was structurally efficient without defect of bonding.

• 상하수도학회지
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• 제24권5호
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• pp.509-517
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• 2010

Statistical distribution of annual maximum rainfall intensity of 18 cities in Korea was analyzed and applied to the reliability model which can calculate the probability of performance failure of storm sewer. After the analysis, it was found that distribution of annual maximum rainfall intensity of 18 cities in Korea is well matched with Gumbel distribution. Rational equation was used to estimate the load and Manning's equation was used to estimate the capacity in reliability function to calculate the probability of performance failure of storm sewer. Reliability analysis was performed by developed model applying to the real storm sewer. It was found that probability of performance failure is abruptly increased if the diameter is smaller than certain size. Therefore, cleaning the inside of storm sewer to maintain the original diameter can be one of the best ways to reduce the probability of performance failure. In the present study, probability of performance failure according to accumulation of debris in storm sewer was calculated. It was found that increasing the amount of debris seriously decrease the capacity of storm sewer and significantly increase the probability of performance failure.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.509-512
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• 2001

Recently, our country's piggery has been becoming large-sized and crowded gradually in scale. Thus, the environment in a piggery is getting worse, which leads to a drop in livestock's immunoactivity. Therefore, livestocks are exposured to many diseases(stress, hypertension, stomach ulcer etc.). In this paper, our intention is to design a low cost ozone-generating device with high capacity to maintain a reasonable ozone level, that is necessary for cleaning the environment in a piggery, but is not too high to cause any harmful influence to human beings and livestock. The results showed that the UV-lamp tube with baffle has an increase of 25% in ozone generation efficiency compared to without baffle and the short retention time of air or high inlet air rate shows high level of ozone.

• 한국정밀공학회지
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• 제1권2호
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• pp.47-57
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• 1984

The porous matterials are used both to control the flow of the compressed gas and to serve as the bearing surface. This porous design offers several advantages over the conventional externally pressurized gas bearings. It can simplify the construction, lower the gas consumption, and make the cleaning of the gas supply less critical. Test apparatus was cinstructed to experi- mentally investigate maximum load capacity of thrust bearing was measured 200 Kg (15Kg/$\mu$m), and radial bearing was 36 Kg/$\mu$m. And a rotation accuracy of face waving was 0.0127$\mu$m, and center waving was measured 0.5 $\mu$m. Finally, the use of this method of design and manufacturing will contribute to many practical application in the field required for precision and high stability.

• 한국연소학회지
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• 제17권3호
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• pp.30-45
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• 2012

An existing unit of power plant is considered to refurbish it for possible application of carbon capture and storage(CCS). Conceptual design of the plant includes basic considerations on the national and international situation of energy use, environmental concerns, required budget, and time schedule as well as the engineering concept of the plant. While major equipment of the recently upgraded power plant is going to be reused, a new boiler for air-oxy fired dual mode operation is to be designed. Cryogenic air separation unit is considered for optimized capacity, and combustion system accommodates flue gas recirculation with multiple cleaning and humidity removal units. The flue gas is purified for carbon dioxide separation and treatment. This paper presents the background of the project, participants, and industrial background. Proposed concept of the plant operation is discussed for the possible considerations on the engineering designs.

• 한국염색가공학회지
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• 제22권1호
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• pp.21-27
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• 2010

The purpose of this research was to investigate the color characteristic and the dyeing properties of Glycyrrhizae Radix extract on cotton fabrics. The highest absorbance of Glycyrrhizae Radix extract was obtained in 75 v/v% of ethyl alcohol in water. Pre-mordanted cotton fabrics dyed at $30^{\circ}C$ and pH 3 for 80 minutes showed the highest K/S value. According to the dyeing conditions, the colors of the fabrics varied from yellow(Y) and yellowish red(YR) to greenish yellow(GY). The color fastness of the fabrics in dry-cleaning and water was 4~5 rating. The deodorization capacity and UV-cut effect of the dyed fabrics were higher than those of undyed ones.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2001-2003
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• 1999

Recently the ozone generation system is well used for cleaning the contaminated water by using the strong oxidization effects of ozone. Ozone generation system is composed of ozone generation device, air or oxygen supply device and high voltage apply device. In this paper, commercial frequency was applied to the wire typed conductor. The ozone concentration was measured with air or oxygen as a supplied gas, which can be used as basic data for the development of ozonizer system.

• 상하수도학회지
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• 제27권5호
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• pp.555-560
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• 2013

A cost analysis method for pretreament processes of a large scale seawater desalination plant was considered using a cost estimation model, WaTER (Water Treatment Estimation Routine). This model is based on cost functions of U.S. EPA to conduct economic analysis of water treatment facilities. A virtual seawater desalination plant which has pretreatment production capacity of $100,000m^3$ per day was chosen as a model plant. Dual media filtration and microfiltration systems were compared as pretreatment process, and the following reverse osmosis process was modeled. As a result, microfiltration showed a price competitiveness in condition of operating with reverse osmosis process by reducing the loads of water treatment and membrane cleaning despite it's high annual cost.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2016년도 추계학술대회 논문집
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• pp.37-38
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• 2016

본 논문에서는 유도가열방식 세정장치의 티타늄 용기 특성을 분석하고 전력변환장치를 설계한다. 코일에 흐를 전류를 계산하기 위한 용량 산정은 기체의 온도 변화량 및 용기 가열 시간을 고려하여 증기 가열에 필요한 열량을 수학적으로 분석하고 설계한 전력변환장치를 시뮬레이션을 통해 검증한다.

• 한국토양환경학회지
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• 제4권1호
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• pp.69-73
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• 1999

PCAPS는 토양 간극수를 효율적으로 포집하기 위해서 fiberglass wick의 모세관 잠재력을 이용하여 토양오염을 조사하는 장치이다. Fiberglass에 붙어 있는 불순물은 wick의 모세관 성질과 포집된 시료의 화학적 성질에 영향을 미치게 되므로 4가지 처리방법들 (소각처리, 아세톤처리, 세정제처리, 비세척)을 이용하여 불순물을 제거하였다. Wick은 미국의 PPG Industries와 Manville Company에서 생산되는 제품을 사용하였다. 실험결과로, PPG fiber는 소각처리에 의해 원래 부피의 3.4%정도 손실되었으며, Manville fiber 는 0.6%미만이 손실되었다. 이들 손실은 제작과정에 사용된 유기합성물이 소각되면서 발생하였다. 모든 세척방법들은 비세척 방법보다 모세관의 상승높이가 더 크게 나타났다. 소각이 가장 좋은 세척방법으로 나타났으며 40$0^{\circ}C$의 온도에서 4시간 처리시 불순물의 98~100%를 제거할 수 있었다.