• 한국염색가공학회지
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• 제34권3호
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• pp.146-156
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• 2022

In this study, the dyeing properties of double knit fabric composed of PET/PTT bi-component fiber and quick dry fiber were examined with disperse dyes. In addition, the shrinkage characteristics were investigated during the dyeing process. The K/S values and shrinkage rate of PET/PTT bi-component fiber were higher than those of PET/co-PET bi-component fiber and quick dry fiber. In the dye bath, dye migration of exhausted on PET/PTT bi-component fiber to quick dry fiber was found at high dyeing temperature. It was not found that there was a significant difference in K/S value on dyeing temperature between 115℃ and 130℃. But the slight color difference of two sides of a double knit fabric was found.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.154-156
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• 2008

A prototype of the desiccant cooling system with a regenerative evaporative cooler was built and tested for the performance evaluation. The regenerative evaporative cooler is to cool a stream of air using evaporative cooling effect without an inc6rease in the humidity ratio. It is comprised of multiple pairs of dry and wet channels and the evaporation water is supplied only to the wet channels. By redirecting a portion of the air flown out of the dry channel into the wet channel, the air can be cooled down to a temperature lower than its inlet wet-bulb temperature at the outlet end of the dry channels. Incorporating a regenerative evaporative cooler eliminates the need for deep dehumidification in the desiccant rotor that is necessary to achieve low air temperature in the system with a direct evaporative cooler. Subsequently, the regenerative evaporative cooler enables the use of low temperature heat source to regenerate the dehumidifier permitting the desiccant cooling system more beneficial compared with other thermal driven air conditioners. At the ARI condition with the regeneration temperature of $60^{\circ}C$, the prototype showed the cooling capacity of 4.4 kW and COP of 0.75.

• 한국유기농업학회지
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• 제15권1호
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• pp.71-84
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• 2007

[ $CO_2$ ] 농도증대와 고온조건이 피망의 생육 및 수량에 미치는 영향을 분석하여 향후 지구 온난화에 따른 작물분야에서의 대응방안 마련을 위한 기초자료를 얻고자 시험한 결과를 하면 다음과 같다. 파종 후 개화소요일은 $CO_2$ 농도처리 간에는 400ppm 처리구에서 56.3일, $CO_2$ 농도를 배증시킨 800 ppm에서는 55.7일로 대차 없었으나, 온도 처리간에는 $35/25^{\circ}C$의 고온구가 52.5일로 가장 짧게 소요되었다. 출현 후 15주의 피망의 생육 및 수량을 보면 초장은 $CO_2$ 농도간에는 유의성이 없었으며, 온도간에는 유의성이 인정되어 $30/20^{\circ}C$ 처리구에서 초장이 54.5cm로 가장 컷다. 생육기간중 경시적인 초장신장은 $CO_2$ 농도가 높은 구에서 초장신장이 억제되었으며, 온도가 높을수록 초장신장이 커졌다. 주당 엽면적은 400ppm 처리구가 평균 $6,008.8cm^2$, 800ppm 처리구가 $5,225.1cm^2$로 400ppm 처리구가 약 15% 엽면적이 높았다. 엽건물중은 $CO_2$ 농도간 및 온도처리간에 유의성을 나타내었다. 800ppm 처리구의 평균 엽건물중은 44.1g으로 400ppm 처리구의 37.2g에 비해 18.5% 높았으며, 온도처리간에는 고온구인 $35/25^{\circ}C$구가 49.8g으로 가장 높았다. 총 지상부 건물중도 $CO_2$ 농도간 및 온도처리간에 유의성을 나타내었으며, 800ppm 처리구가 141.4g으로 400ppm 처리구의 119.9g보다 17.9%나 높았다. 온도처리별 지상부 건물중은 $30/20^{\circ}C$ 처리구가 168.9g으로 가장 높았으며, 고온구인 $35/25^{\circ}C$구가 102.3g으로 가장 낮았다. 과실의 건물중(수량)은 800ppm 처리구가 59.5g으로, 400ppm 처리구의 44.3g에 비해 약 34.3% 많아 피망의 경우 $CO_2$, 농도 증대가 수량증대에 유리할 것으로 판단되었으며, $CO_2$, 농도가 높을 때(800ppm)에는 저온($25/15^{\circ}C$)에서, 평상적인 $CO_2$, 농도에서는 고온($30/20^{\circ}C$) 조건에서 수량이 높아지는 경향이었다. $CO_2$, 농도에 따른 비엽면적은 800ppm의 117.4보다는 400ppm의 159.1에서 35.5% 커, $CO_2$, 농도가 증대하면 잎의 두께가 두꺼워짐을 알 수 있었다. 또한 작물학적 특성들간 상관관계를 보면 엽면적은 주당 착과수 및 과실 건물중과 유의한 부의 상관관계를 나타내어 엽면적이 클수록 수량은 낮아졌다. 주당 과실 건물중과 주당 착과수, 지상부 총건물중과는 유의한 정의 상관관계를 보여 착과수가 많을수록 지상부 건물중이 클수록 수량이 증대함을 알 수 있었다.

• 한국대기환경학회지
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• 제6권1호
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• pp.85-96
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• 1990

Simultaneous removal efficiencies of hydrophilic and hydrophobic gaseous pollutants are experimentally determined, and the macroscopic removal mechanism of pollutants in a dry scrubber is analyzed using the extended model of three phase equilibrium distribution of pollutant at high temperatures that can describe the different morphological conditions of adsorbent and water at varying relative humidities. For the simplicity, the inside of spray dryer is divided into three regions of ; (1) absorption, (2) three-phase equilibrium, and (3) adsorption, and the removal efficiencies of each pollutants at three regions are observed at different experimental conditions to estimate the effects of important parameters of dry scrubber. The laboratory experiments simulate the three regions of spray dryer with the temperature control and thus evaporation rate of water from the slurry particle. $SO_2$ as a hydrophilic gaseous pollutant and vinyl chloride as a hydrophobic toxic gas are selected for the future field application to soid waste incineration, and the two types of slurry are made of the two sorbents ; 10 wt.% $Ca(OH)_2$, and 10 wt.% NaOH. Result of temperature effect shows the height of absorption plus three-phase region is decreased as the operation temperature is increased, which results in the lower removal efficiency of $SO_2$ but higher removal for vinyl chloride in the adsorption region of dry scrubber. The removal efficiency of $SO_2$ is higher by NaOH slurry than by $Ca(OH)_2$ slurry due to the hygroscopic nature of NaOH, while the removal of vinyl chloride is higher in $Ca(OH)_2$ case. From the analysis of redults using three-phase equilibrium distribution model, the effective two-phase partition coefficients can be obtained, and the possible extention in the application of the three-phase equilibrium model in a dry scrubber design has been demonstrated.

• 드라이브 ㆍ 컨트롤
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• 제12권1호
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• pp.1-8
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• 2015

The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.

• Korean Chemical Engineering Research
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• 제56권2호
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• pp.176-185
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• 2018

지구 온난화가 가속화됨에 따라 온실가스 감축이 보다 중요해졌다. 이산화탄소 건식 개질은 온실가스인 $CO_2$와 $CH_4$를 활용하여 부가가치가 높은 물질인 CO와 $H_2$를 얻을 수 있는 유망한 온실가스 감축 기술이다. 그러나 이 반응이 일어나는 반응기의 운전 중에 심각한 코킹 문제가 발생할 수 있다. 이산화탄소 개질반응은 매우 강한 흡열반응이기 때문에 반응기 입구 근처에서 반응 온도가 많이 떨어지면서 코크 생성을 야기시킨다. 이러한 문제를 해결하기 위해서는 코크 생성이 잘 일어나지 않는 온도영역에서 반응이 일어나도록 하는 것이 중요하다. 본 연구에서는 새로운 촉매 배열 방법을 이용하여 반응기 전 구간이 코크 생성이 잘 일어나지 않는 온도 영역 내에서 유지되도록 하는 설계 방법을 제안하였다. 이 설계 방법은 연료 유량, 촉매 밀도, 구간 별 출구 온도를 최적화 변수로 하여 주어진 전환율에 대하여 반응기 길이를 최소화 할 수 있는 최적화 문제를 풀도록 하여 반응기를 최적화한다.

• Nuclear Engineering and Technology
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• 제39권2호
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• pp.143-148
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• 2007

Spent nuclear fuel generated at nuclear power plants must be safely stored during interim storage periods. A dry storage cask to safely store the spent nuclear fuel should be able to adequately emit the decay heat from the spent nuclear fuel. Therefore, heat removal tests using a half scale dry storage cask have been performed to estimate the heat transfer characteristics of a dry storage cask under normal, off-normal, and accident conditions. In the normal condition, the heat transfer rate to an ambient atmosphere by convective air through a passive heat removal system reached 83%. Accordingly, the passive heat removal system is designed well and works adequately. In the off-normal condition, the influence of a half blockage in the inlet on the temperature appears minimal. In the accident condition, the temperature rose for 12 hours after the accident, but the temperature rise steadied after 36 hours.

• 한국재료학회지
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• 제14권10호
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• pp.743-748
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• 2004

Modified Ni/YSZ cermets for high temperature electrolysis were synthesized by the direct ball milling of Ni and YSZ powder. The ball milling was carried out in dry process and in ethanol with varying milling time. While the dry-milling decreased the average size from 65 to $80{\mu}m$, the wet-milling decreased the average size down to $10{\mu}m$. In addition, very fine particles less than $0.1{\mu}m$ were observed in the wet-milling condition. The subsequent process of cold-pressing and sintering at $900^{\circ}C$ for 2 h did not affect the particle size of dry-milled powder. The electrical conductivity of the dry-milled Ni/YSZ cermet showed the value of $5{\times}10^{2}\;S/cm$ and this value was increased to $1.4{\times}10^{4}\;S/cm$ after the sintering at $900^{\circ}C$ for 2 h.

• 동력기계공학회지
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• 제19권4호
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• pp.50-55
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• 2015

Recently, because of the deterioration of the nuclear generating station and increase of the cooler and heater, energy problem is increasing. To save the energy, the free cooling system is developed. The free cooling system is that cool the water to use cooled air in winter and is used in industrial process or data center. Yoon check the energy of free cooling system with dry cooler in korea. In this study, the value of the free cooling system with dry cooler is confirmed through using the NPV that is economic evaluation. when temperature degree of the cooled water is 10, in Chuncheon and Seoul the value is the most high. When temperature degree of the cooled water is 20, in Ulsan the value is the most high. As the result, because the using the temperature degree of the cooled water is high in the industrial process, the free cooling system is advantageous in korea.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.922-925
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• 2007

In the usual dry etching process for the TFT-LCD fabrication, it is hard to monitor the basic plasma parameters such as density and temperature. However, the basic parameters are easily monitored during the dry etching process. We have simultaneously measured the electric characteristics and basic plasma parameters of the dry etching chamber during the process, analyzed them to interpret plasma parameters. For the Ar plasma discharge case, we could obtain the density and temperature from the electric characteristics using a simple simple sheath model.