• 생명과학회지
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• 제24권4호
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• pp.419-427
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• 2014

인진쑥(Artemisia capillaris Thunbl)의 항산화적 특성을 조사하기 위하여 반응표면분석법에 의하여 열수추출특성을 모니터링하여 최적 추출조건을 설정하였다. 총 페놀성화합물 함량에 대한 최적조건은 $94.50^{\circ}C$, 2.06 hr 및 시료에 대한 용매비 25.03 ml/g, 전자공여능에 대한 최적조건은 $91.82^{\circ}C$, 2.90 hr 및 20.88 ml/g으로 나타났고, 아질산염 소거능(pH 1.2)에 대한 최적조건은 $97.36^{\circ}C$, 2.75 hr 및 15.19 ml/g등으로 각각 나타났다. 각 변수에 대한 회귀식을 도출하여 인진쑥의 총 페놀성화합물 함량, 전자공여능 및 아질산염 소거능(pH 1.2)에 대한 최적 추출조건을 superimposing 한 결과, 추출온도 $90{\sim}95^{\circ}C$, 추출시간 2.5~3.5 hr 및 시료에 대한 용매비 17~24 ml/g의 범위로 각각 예측되었다.

• 인터넷정보학회논문지
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• 제17권5호
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• pp.111-119
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• 2016

In recent years, the opinion analysis is one of the key research fronts of any domain. Opinion target extraction is an essential process of opinion analysis. Target is usually referred to noun or noun phrase in an entity which is deliberated by the opinion holder. Extraction of opinion target facilitates the opinion analysis more precisely and in addition helps to identify the opinion polarity i.e. users can perceive opinion in detail of a target including all its features. One of the most commonly employed algorithms is a sequence labeling algorithm also called Conditional Random Fields. In present article, recent opinion target extraction approaches are reviewed based on sequence labeling algorithm and it features combinations by analyzing and comparing these approaches. The good selection of features combinations will in some way give a good or better accuracy result. Features combinations are an essential process that can be used to identify and remove unneeded, irrelevant and redundant attributes from data that do not contribute to the accuracy of a predictive model or may in fact decrease the accuracy of the model. Hence, in general this review eventually leads to the contribution for the opinion analysis approach and assist researcher for the opinion target extraction in particular.

• Elastomers and Composites
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• 제33권3호
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• pp.201-209
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• 1998

고무배합물의 충진제로 사용되는 알루미나 분말의 제조에 있어서 재래식 및 마이크로파 에너지원에 의하여 황산용액중의 카올린으로 부터 알루미나를 얻는다. 이때 카올린으로부터 알루미나 분말의 최대 추출율은 각각 재래식의 경우는 $80^{\circ}C$, 1M 황산, 180분에서 72.8%이고, 마이크로파 추출 공정의 경우는 $90^{\circ}C$, 1m 황산, 60분에서 $99\%$였다. 또한 추출된 시료는 TG/DTA, XRD, SEM, Atomic Emission Spectroscopy 및 BET법에 의하여 분석하였다..

• 한국염색가공학회지
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• 제24권4호
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• pp.253-259
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• 2012

In this work, the natural indigo production process from Polygonum tinctorium was balanced based on the traditional Niram method in Korea. A standard procedure was determined considering the conditions of indican extraction from plant material, the amount of alkali for precipitation, storage of extract, etc. The effect of experimental conditions on the yield of crude dye was investigated. The contents of indigo and indirubin of the crude dyes were analyzed by HPLC. Increase of the amount of crude dye was observed within 1-2.5 days of extraction time. Longer extraction beyond 2.5 days resulted in a slight decrease in the amount of crude dye. There was no consistency in terms of indigo content depending on extraction pH. We found that the storage of extract or harvested plants affected adversely to dye yield and dye quality. Based on the lab scale extraction, large scale extraction was performed for 2-2.5 days in water and 2.0-2.5 g/L of $Ca(OH)_2$ was applied for precipitation of indigo dye. We obtained natural indigo dye containing about 15% of pure indigo in scale-up production using whole plant except root.

• 한국환경과학회지
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• 제28권11호
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• pp.927-933
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• 2019

A lipid-enriched strain of Botryococcus braunii (UTEX 572) was cultivated in a semi-batch aeration tank to enhance biomass as well as to develop intracellular lipids and fatty acids. A 30 day period of incubation produced 1.39 g/L of biomass and 0.31 g/L of total lipids in the biomass. The grown biomass was pre-treated using several methods to extract the total lipid content efficiently: ultrasonication was found to yield the highest percentage of lipids-namely 19.8% per biomass. Direct heating of biomass in an autoclave also showed better performance than when using only conventional solvent extraction. To enhance the biomass harvest and lipid extraction efficiency, coagulation and flocculation steps were added to the extraction process. It is noteworthy that not only the solvent type but also the solvent/biomass ratio greatly affected efficiency. In addition, the moisture content of the harvested(wet) biomass affected the efficiency significantly. This study elucidated the need for future research on optimizing this extraction process.

• 한국환경과학회지
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• 제6권2호
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• pp.133-139
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• 1997

말로네이트 제조 공정에서 발생되는 폐액으로부터 용매추출법을 적용하여 코발트 회수 연구를 하였다 용매 추출에서의 주요 변수는 용매의 선택, pH, 코발트 농도, 역추출 온도 등이며 이러한 변수들의 영향을 조사하였다. 용매로써 DEHPA와 PC88A가 사용되었으며 이들 용매의 평형추출 곡선을 구하였다. 공장설계 조건을 찾기 위하여 Mccabe-Tiele 선도를 작성하였고, 연속 공정인 믹서-세틀러 장치를 가동하였다. 본 연구 결과 폐액 중에서 코발트는 99.9% 이상 회수되었고, 회수된 황산코발트의 순도는 99.9% 이상이었다.

• KSBB Journal
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• 제15권4호
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• pp.408-410
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• 2000

생리활성물질의 함유량이 많은 아가리쿠스버섯으로부터 초임계 유체 추출 기술을 이용하여 비극성 생리활성물질인 linoleic acid를 분리, 정제하였다. Gas chromatography - mass spectrometer를 이용하여 추출된 물질의 정성분석을 수행하여 추출된 물질은 약리작용 효과를 가지는 linoleic acid (cis-9, cis-12-octadecadienoic acid)로 분석되었다. 초임계 추출법을 이용한 아가리쿠스 버섯으로부터의 생리활성물질 추출공정의 최적화를 위하여 다양한 온도와 압력하에서 실힘을 수행하였으며 추출 효율을 비교한 결과 $50^{\circ}C, 200 kg_f/cm^2$의 최적 운전조건을 결정하였다.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.1-5
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• 2005

The digital HPTV velocity field measurement consists of four steps: recording, numerical reconstruction, particle extraction and velocity extraction. In the velocity extraction process, we improved PTV algorithm to extract the displacement of particle each placed in 3D space. Because a digital recording device was used, some factors such as a spatial resolution, numerical aperture, and particle concentration can affect the performance of the digital HPTV. Especially, a particle concentration ($C_{o}$) affected tile reconstruction efficiency in numerical reconstruction and particle extraction process. In this paper, the reconstruction efficiency was analyzed experimentally with different particle concentration. Optimal reconstruction efficiency was shown in the range of $C_{o}$=$13\∼15$ particles/$mm^{3}$.

• Preventive Nutrition and Food Science
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• 제14권2호
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• pp.129-133
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• 2009

Salicornia herbacea is rich in natural minerals, dietary fibers, and potentially health-promoting phenolic compounds. In this paper, an experimental design was applied for the optimization of the ultrasound-assisted extraction of phenolic compounds from lyophilized Salicornia herbacea powder. The experiments were conducted in accordance with a five-level, three-variable central composite rotatable design (CCRD), and the effects of solvent concentration, extraction time, and extraction temperature were evaluated via response surface methodology (RSM). The optimal extraction conditions were as follows: ethanol concentration, 76.80%; extraction time, 20 min; and extraction temperature, $33.21^{\circ}C$; and the solvent concentration was the most significant parameter in this process, under which the predicted total phenolic content was 49.91 mg GAE/g sample.

• 대한가정학회지
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• 제39권4호
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• pp.49-59
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• 2001

Natural red and yellow dyestuff was extracted from safflower (Carthamus tinctorius Linnaeus) by a new process of cellulase extraction compared with the conventional hot water extraction. Dyestuffs were extracted from safflower easily and repeatedly by means of cellulose as safflower cell wall destroyer. It means that new dyestuff extraction by cellulase improves not only yields of dyestuff from safflower successfully but also the rate of repetition of extraction. From the above experiments, the conclusions of this study were summarized as follows. 1. The optimum conditions of dyestuff extraction from safflower by general extraction method were that the solvent was the water of pH 6.0 on yellow dyestuff and 3% $K_2CO_3$ solution on red dyestuff, extraction temperature was $55^{\circ}C$, and extraction time was 30 min. 2. Among various cellulase, the NOVO cellulase was the best cell wall destroyer of safflower and finally produced the largest amount of dyestuff from safflower by cellulase extraction method. 3. The optimum conditions of dyestuff extraction by cellulase extraction method were conducted on 10 unit of cellulase per gram of safflower at $100m{\ell}$ water of pH 5.0 at $50^{\circ}C$ for 30 min.