• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.446-451
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• 2003

인화점은 가연성 액체의 화재 위험성을 나타내는 지표로써, 가연성액체의 액면 가까이서 인화할 때 필요한 증기를 발산하는 액체의 최저온도로 정의한다. 인화점에는 하부인화점과 상부인화점으로 나누고 있으며, 일반적으로 하부인화점을 인화점이라 한다.(중략)

• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.283.2-283
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• 2001

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.137-138
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• 2006

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2012.10a
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• pp.291-292
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• 2012

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.776-784
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• 2016

In this study, green Larix kaempferi lumber was heat-treated by using superheated steam (SHS) at a pilot scale and then various physico-mechanical properties of the heat-treated wood were evaluated and compared with the properties of conventional hot air (HA) heat-treated wood. Decay resistance of brown rot fungi and compressive strength parallel to the grain of the SHS heat-treated wood without occurrence of drying check from green lumber were increased. On the other hand, density, equilibrium moisture content, shrinkage, and bending strength of the SHS heat-treated wood were lower than those of the conventional HA heat-treated wood. Because heat transfer and thermal hydrolysis of SHS heat treatment was accelerated by a large amount of water, the effect of SHS heat treatment on the physico-mechanical properties was higher than that of HA heat treatment at the similar conditions of temperature and time. From the results of this study, because green lumber can be heat-treated without occurrence of cracks or checks by using SHS and similar heat treatment effect on the physico-mechanical properties of wood can be produced despite a low temperature or short time of heat treatment, it is expected that heat time and energy consumption could be reduced by using SHS.

• Journal of Energy Engineering
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• v.6 no.1
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• pp.104-113
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• 1997

This study aims to develop an analysis model using a commercial process simulator-ASPEN PLUS for an IGCC (Integrated Gasification Combined Cycle) system consisting a dry coal feeding, oxygen-blown entrained gasification process by Shell, a low temperature gas clean up process, a General Electric MS7001FA gas turbine, a three pressure, natural recirculation heat recovery steam generator, a regenerative, condensing steam turbine and a cryogenic air separation unit. The comparison between those results of this study and reference one done by other engineer at design conditions shows consistency which means the soundness of this model. The greater moisture contents in Illinois#6 coal causes decreasing gasifier temperature and the greater ash and sulfur content hurt system efficiency due to increased heat loss. As the results of sensitivity analysis using developed model for the parameters of gasifier operating pressure, steam/coal ratio and oxygen/coal ratio, the gasifier temperature increases while combustible gases (CO＋H2) decreases throughout the pressure going up. In the steam/coal ratio analysis, when the feeding steam increases the maximum combustible gas generation point moves to lower oxygen/coal ratio feeding condition. Finally, for the oxygen/coal ratio analysis, it shows oxygen/coal ratio 0.77 as a optimum operating condition at steam/coal feeding ratio 0.2.

• Food Science and Preservation
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• v.24 no.5
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• pp.600-607
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• 2017

This study was conducted to develop radish as a food product for home meal replacement using superheated steam (SHS). Also, the change of quality characteristics was studied during their storage. The radish cuts were treated with SHS for 0, 3, 5, and 7 min, respectively, followed by complete drying at $80^{\circ}C$ for 6 hours. The results showed that radishes restored with mixed solution (drinking water:sugar:vinegar:salt=2:1:0.8:0.1) were harder than those restored with drinking water. All radishes were stored at 5, 10 and $15^{\circ}C$ for 56 days to investigate the changes of quality characteristics during the storage. Radishes in the control group, restored with drinking water and stored at $15^{\circ}C$, were spoiled after 7 days of storage. The radish in the experimental group did not show any change in the water content; except an increase on the first day of storage. The hardness of radish decreased with an increase in the storage period. It was found that microbial growth was inhibited due to low pH of the mixed solution, in which radishes of the experimental group were immerse.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.361-363
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• 2008

탄소 개질반응은 $1200^{\circ}C$(도1) 이상에서 모든 탄화물질과 수분 또는 $CO_2$ 사이에서 흡열/환원반응이 일어나서 합성가스를 생성한다. 개질반응로는 산화반응로와 연결되어, 수소가스와 CO 가스의 혼합인,합성가스가 산화반응로 내에서 산소가스와 연소하여 열과 $H_2O+CO_2$를 생성하여 환원 반응로 내로 유입되어, 환원 반응로를 $1200^{\circ}C$ 이상으로 유지하고, $H_2O$와 $CO_2$는 석탄 속의 모든 탄소를 CO로 개질한다(도2). 동시에 수소가스가 생성되어 합성가스를 생성하게 된다. 석탄 속의 비탄소 물질인 슬래그(Slag)는 개질로 내에 남게 되는데, 개질로를 슬래그 융점(non-fluid point) 이하에서 고체상태로 포집함으로서 Fly-ash로 처리된다. 개질로 내의 온도를 $1200{\sim}1300^{\circ}C$(석탄 슬래그 융점)로 유지함으로서 개질반응이 지속되어 합성가스가 생성된다. IGCC 시스템에서는 합성가스를 가스터빈 속에서 $O_2E가스와 연소하여 고온의 가스를 생성하여 터빈을 가동해 발전을 하고 배출가스를 $1500{\sim}1700^{\circ}C$에서 배출한다. 재래식 IGCC(도4)에서는 ${\sim}1500^{\circ}C$의 배출가스를 열교환 시스템에 의해 증기를 생성하여 Steam turbine(증기터빈)을 가동하여 추가 전력을 생산했다. 그러나 본 시스템에서는 배출가스(증기와 $CO_2E 가스)를 위의 개질로에 유입하여 개질로 온도를 $1200{\sim}1300^{\circ}C$로 유지함으로서 더 많은 합성가스를 생성 하게 된다(도3). 이렇게 하여 Oxidation-reduction cycle을 형성하게 된다. 새로운 IGCC 시스템에서 가스 터빈의 배출가스가 석탄 개질로에 연결되고 석탄개질로의 합성가스 출구가 가스터빈의 가스 입구에 연결됨으로서,외부에너지 주입 없이 지속 가능한 가스화 반응과 터빈 사이클(Cycle)을 완성하여 IGCC 시스템의 석탄 열효율을 1단계 상승시켰다. 이렇게 설계된 석탄가스화기는 Lurgi형 석탄가스화 기와 달리 석탄개질반응의 효율을 높일 수 있고, 슬래그 처리가 간단하기 때문에 석탄가스화기가 소형화 될 수 있으며 슬래그(Slag)용융에 따른 석탄가스화기의 외벽손상을 피할 수 있다.

• Membrane Journal
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• v.17 no.2
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• pp.140-145
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• 2007

In this study, 3-(trihydroxysilyl)-1-propanesulfonic acid (THS-PSA) was added to poly(vinyl alcohol) (PVA) membranes crosslinked with poly(styrene sulfonic acid-co-maleic acid) (PSSA_MA) to improve the separation characteristics toward water vapors in the air. The prepared membranes varying both PSSA_MA and THS-PSA amounts were also synthesized at different cross linking temperatures. Then, in order to investigate the separation characteristics of the resulting membranes, the dynamic vapor sorption (DVS) and vapor permeation experiments were carried out. The increase of cross-linking temperature showed longer time to reach the equilibrium sorption state from the dynamic vapor sorption experiments. PVA/PSSA_MA (3%)/THA-PSA(7%) prepared at $120^{\circ}C$ gave the highest permeability of 480 barrer at $35^{\circ}C$.

• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.174-179
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• 2007

Although the relationship between fermentation and factors such as soil water, redox potential, rootstocks and climatic conditions has been reported, its mechanism of fermentation is still not clear. Transpirations of leaf and fruit at different climatic conditions, influence of soil water potential and atmospheric vapor pressure deficit (VPD) on fermentation were evaluated. Transpiration rate decreased with decreasing soil temperature and soil water potential. Low VPD conditions which occurred during low air temperature and high humidity also decreased transipration rate. These data exhibit that fruit water balance affected by various factors relate to transpiration. Our results also indicate that high hydraulic conductance of root, high soil water potential and low VPD condition exert a significant effect on fermention of oriental melon and so called "water filled fruit".