• Clean Technology
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• v.14 no.4
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• pp.275-280
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• 2008

In this study, we carry out economic and technical feasibility study for treatment process of waste solvent such as SD waste solution and stripper solution from LCD manufacturing process. Extensive screening work has been done for selecting the best extraction solvent. As a result, it is shown that $CHCl_3$ is the most adequate extraction solvent for separation and recovery of both SD waste solvent and stripper waste. Rigorous simulation study has been carried out for extraction process and distillation process as a candidate of waste solvent treatment. The result shows that the solvent extraction process is more beneficial than the simple distillation process.

• Proceedings of the Korean Statistical Society Conference
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• 2002.11a
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• pp.135-140
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• 2002

변량추출비 관리도는 현재의 관측값에 기초하여 다음 시점의 표본크기와 표본추출간격을 변화시키면서 공정의 변화를 탐지하는 관리도 절차이다. 만일 공정에서 추출한 현재의 관측값을 살펴볼 때 공정변화의 징후가 있는 경우에는 다음 시점의 표본추출비를 증가시켜, 즉 표본크기를 크게 하고 표본추출간격을 작게 하여 예상되는 공정변화를 더 빠르고 정확하게 탐지함으로보다 효율적인 공정관리를 수행하는 것이다. 본 연구는 변량추출비 ${\bar{X}}$ 관리도에서 사용하는 표본크기와 표본추출간격의 수를 달리하며 각각의 경우에 대한 통계적 효율을 계산하고 이를 비교하고자 한다.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.576-583
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• 2019

The effect of aeration process in causing changes in the prosapogenin content and the antioxidant activity of red ginseng powder extracts was investigated. With respect to the color change of the extracts, the L-value and b-value decreased significantly with the lapse of extraction time both with and without the aeration process. The a-value increased with the lapse of the extraction time in the non-aeration process but decreased in the aeration process. This result suggests that when the aeration process was performed, the lightness, yellowness, and redness decreased with the lapse of the extraction time, resulting in a darker color. The total polyphenolic and total flavonoid contents were the highest at 0.84 and 0.96 mg Gallic Acid Equivalent (GAE)/mL, 21.77 and 21.93 mg GAE/mL at 24 h and 36 h, respectively for the aerated red ginseng powder extracts. The DPPH, ABTS, H₂O₂ scavenging activity, and reducing power were measured to confirm the antioxidant effects of red ginseng powder extracts after the aeration process. Thus, the antioxidant activity was increased in the aerated red ginseng powder extracts. In addition, when comparing the contents of Rb1, Rg1, and Rg3, the content of Rg3 was significantly different, and it was confirmed that a large amount was produced in the aerated red ginseng extracts. These results indicate that the red ginseng extracts subjected to the aeration process are superior than the ones processed by the non-aeration process.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.2
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• pp.141-151
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• 2013

Process planning can be defined as determining detailed methods by which parts can be manufactured from the initial to the finished stage. Process planning starts with determining the manufacturing process based on the geometric shape of the part and the machines and tools required for performing this process. Distributed process planning enables production planning to be performed easily by combining the extracted process and various manufacturing resources such as operations and tools. This study proposes an algorithm to determine the process for a feature-based model and to combine manufacturing resources for the process and implements a distributed process planning system.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.853-858
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• 1995

$^{152}$EU, $^{241}$Am 및 $^{241}$Np를 선정하여 추출제 di-(2-ethylhexyl)phosphoric acid (DEHPA)로 이들 세가지 핵종의 상호 분리공정에 대해 연구하였다. 추출공정에서 질산농도는 0.IM이고 추출 제DEHPA/n-dodecane 농도가 IM 일때, $^{152}$Eu 및 $^{241}$Am, $^{241}$Np 핵종 모두 99.9% 이상 추출되었다. $^{241}$Am 핵종의 역추출을 위한 제 1 역추출공정에서 역추출제인 0.05M di-ethylenetriamine pentaacetic acid (DTPA)와 1.5M 젖산 (lactic acid) 혼합용액의 pH가 3.6 일때 $^{152}$Eu과 $^{241}$Am의 상호분리비와 역추출율이 가장 좋았다. $^{152}$Eu의 역추출을 위한 제 2 역추출단계에서 역추출제인 질산용액의 최적농도는 6M이며, 이때 $^{152}$Eu은 99%가 역추출되었다.$^{241}$Np 핵종의 역추출을 위한 제 3 역추출공정에서 역추출제는 0.5M 옥살산이며, 이때 $^{241}$Np은 92%가 역추출되었다.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.284-291
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• 2009

This study was conducted to characterize the enhanced antioxidant and anticancer activities of Berberis koreana bark following a low temperature and high pressure extraction process. The results indicate that the B. koreana bark extracted as described showed a 93% increase in DPPH radical scavenging activity. Inhibition activity of xanthine oxidase was highest by this extraction process. In addition the growth of human lung cancer cells (A549), human stomach cancer cells (AGS), human breast cancer cells (MCF-7) and human liver cancer cells (Hep3B) were inhibited by 70.8%, 86.2%, 84.3% and 62.5% respectively. These data indicate that this low temperature and high pressure extraction technique results in the efficient extraction of bioactive compounds from rigid plant materials. This process could also be combined with other techniques to improve extraction yields and identify new biologically active substances from relatively hard plants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.471-476
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• 2014

We developed a method for improving the antioxidant activities of blueberry (Vaccinium ashei) extracts through an ultra high-pressure extraction process. Blueberries were subjected to water extraction at $60^{\circ}C$ and 300 MPa for 5 min (High Pressure Extraction, HPE5) and 15 min (HPE15). Extraction yields obtained by ultra high-pressure extraction process were 18.48, and 19.89%, respectively. Total polyphenol contents were estimated to be 28.3, and 28.9 mg/g, whereas flavonoid contents were measured as 5.9 and 6.0 mg/g, respectively. Generally, HPE resulted in higher yields than the conventional extraction process. Further, HPE15 showed 53.84% DPPH radical scavenging activity (EDA, %) at $1,000{\mu}g/mL$. Reducing power of HPE15 showed its highest activity of 0.21. In general, antioxidant activities of blueberry increased by HPE. Therefore, HPE of blueberry resulted in higher antioxidant activity than conventional water extraction. These results demonstrate obvious advantages in terms of higher efficiency, shorter extraction time, and lower energy costs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.891-895
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• 2017

This study was performed to investigate enhancement of antioxidant activities of Crataegus pinnatifida Bunge fruit by different extraction processes. Extracts were SE (stirrer extraction; 70% ethanol extract at $25^{\circ}C$, control), RE (reflux extraction at $60^{\circ}C$), and USE (ultrasonification for 3 h at $60^{\circ}C$ with 70% ethanol), respectively. Compared to SE, total phenolic and flavonoid contents in USE increased to 104.03% and 302.4%, respectively. USE showed the highest activity at 1.0 mg/mL concentration for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. Our results suggest that extracts from the ultrasonification process have relatively high antioxidative activities, and that fruit of Crataegus pinnatifida Bunge could be considered as a candidate functional antioxidant agents. These results would be useful for chemical and biological studies on natural plants and its products.

• Clean Technology
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• v.13 no.4
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• pp.274-280
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• 2007

A liquid-liquid solvent extraction process was developed in this study to recover Fe and Ni from heavily concentrated aqueous ferric chloride solution, in an effort to substitute the conventional iron reduction method. Solvent composition and extraction conditions were first developed from the laboratory experiments, and the pilot system was designed and built for commercialization. Stage numbers for extraction and stripping were determined from pilot plant runs, and other operation data were obtained for mass production.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.13-21
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• 2014

We developed a method for improving the antioxidant activities of Citrus extracts through cyclic low pressure drying(CLPD) and a high hydrostatic pressure extraction (HPE) process. Citrus fruits were prepared for water extraction at $60^{\circ}C$ and 300 MPa for 5 min (high hydrostatic pressure extraction, HPE5) and 15 min (high hydrostatic pressure extraction, HPE15) after cyclic low pressure drying method. Extraction yields obtained by cyclic low pressure drying and high hydrostatic pressure extraction process were 20.41, 23.47, and 28.19%, respectively. Total polyphenol contents were increased by combined process. Generally, CLPD and HPE resulted in higher yields than the conventional extraction process. Further, HPE15 showed 48.21% DPPH radical scavenging activity (EDA, %) at $1,000{\mu}g/mL$. In general, antioxidant activities of Citrus increased by CLPD and HPE. Therfore, CLPD and HPE of Citrus resulted in higher antioxidant activity than conventional water extraction.