• Title/Summary/Keyword: Extraction method

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Keyword Extraction in Korean Using Unsupervised Learning Method (비감독 학습 기법에 의한 한국어의 키워드 추출)

  • Shin, Seong-Yoon;Rhee, Yang-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.6
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    • pp.1403-1408
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    • 2010
  • Korean information retrieval uses noun as index terms or keywords of representing the document. and noun and keyword extraction is to find all nouns presented in the document, In this paper, we proposes the method of keyword extraction using pre-built dictionary. This method reduces the execution time by reducing unnecessary operations. And noun, even large documents without affecting significantly the accuracy, can be extracted. This paper proposed noun extraction method using the appearance characteristics of the noun and keyword extraction method using unsupervised learning techniques.

Extraction of Red Ginseng Extract by Impulse Vacuun System (Impulse-Vacuum System을 이용한 홍삼엑스의 추출)

  • 김천석;곽이성;신창식
    • Food Science and Preservation
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    • v.6 no.3
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    • pp.324-327
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    • 1999
  • This study was carried out to establish the extraction method of red ginseng extract without saponin decomposition. Red ginseng was extracted with impulse vacuum system and multi-stage extraction method. Crude saponin content of red ginseng extract (RGE) from impulse vacuum system was 5.4-5.9%, while that of RGE from multi-stage extraction method was 8.2-8.3%. However, HPLC Patterns indicated that saponins of RGE from impulse vacuum system were hardly decomposed, while those of RGE from multi-stage extraction method were decomposed, especially in ginsenoside -Rgl and -Re saponin. Also, the yields of red ginseng by impulse vacuum system were 15 to 20 times higher than that of multi-stage extraction method.

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Study on the Comparison of Effects by Extraction Methods of Roast and Raw Semen Zizyphi Spinosae (생산조인(生酸棗仁)과 초산조인(炒酸棗仁)의 추출방법에 따른 효능비교연구)

  • Lee, Eun-Kyoung;Hong, Hak-Gi;Chong, Myong-Soo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.6
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    • pp.1416-1422
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    • 2009
  • To observe the difference and change of the efficacy and ingredient appearing according to whether semen zizyphi spinosae has been roasted and its extraction method, locomotor activity, anticonvulsant activity, sleeping effect of each hot water and UMPM low temperature extracts of roast and raw semen zizyphi spinosae were measured through animal tests. Roast semen zizyphi spinosae showed superior pharmacological efficacy than raw semen zizyphi spinosae. Also, hot water extraction method showed superior pharmacological efficacy than low temperature extraction method(UMPM) that uses ultrasonic waves and microwaves. In short, it was shown that herbal medicine's extraction method needs to maximize medicinal effects by trying optimum extraction methods according to efficacy by considering characteristics of each herbal medicine. Together, there's also the need for in-depth studies on water-soluble ingredients of semen zizyphi spinosae that may be extracted through full hot water extraction method.

Keyword Extraction Using Unsupervised Learning Method (비감독 학습 기법에 의한 키워드 추출)

  • Shin, Seong-Yoon;Baek, Jeong-Uk;Rhee, Yang-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2010.05a
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    • pp.165-166
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    • 2010
  • Noun extraction is to find all nouns presented in the document, Korean information retrieval uses noun as index terms or keywords of representing the document. In this paper, we proposes the method of keyword extraction using pre-built dictionary. This method reduces the execution time by reducing unnecessary operations. And noun, even large documents without affecting significantly the accuracy, can be extracted. This paper proposed noun extraction method using the appearance characteristics of the noun and keyword extraction method using unsupervised learning techniques.

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Development of Fast Screening Method for Crop Protection Agents in Tobacco by Stir Bar Sorptive Extraction and Thermal Desorption coupled to GC/MS

  • Min, Hye-Jeong;Lee, Jeong-Min;Shin, Han-Jae;Lee, Moon-Yong;Jang, Gi-Chul
    • Journal of the Korean Society of Tobacco Science
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    • v.36 no.1
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    • pp.26-33
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    • 2014
  • Simultaneous determination of crop protection agents(CPAs) in food are done with multi-residue methods, which are composed of sample clean-up, concentration, chromatographic separation and detection. Stir Bar Sorptive Extraction(SBSE) technique is used for sample preparation of various analytes in several fields. The aim of this study was to develop a sensitive and fast method based on SBSE followed by thermal desorption - gas chromatography - mass spectrometry(TD - GC/MS) to determine CPAs in tobacco sample. For the analysis of tobacco sample prior to the SBSE method, solvent extraction or ultrasound-assisted solvent extraction was performed. methanol was used as the extraction solvent. The extract was then diluted with water. Finally, the sample was subjected to SBSE. A method for fast screening of crop protection agents in tobacco using SBSE-TD - GC/MS has been developed. About 17 CPAs including organochlorine, organophosphorous and others were identified and quantified. This method showed good linearity and high sensitivity for most of the target CPAs. The method was applied to the determination of CPAs at ng/mL levels in tobacco sample. This method is simple, rapid and may be applied in detection of other components.

A Comparison of Efficiency of Two Pretreatment Methods for Extracting Heavy Metals from Welding Fume Samples (용접흄내 중금속분석시 전처리 방법별 효율비교)

  • Son, Dooyoung;Kim, Hyunwook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.9 no.2
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    • pp.135-144
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    • 1999
  • The purposes of this study were to survey types of pretreatment methods adopted by industrial hygiene laboratories in Korea for extracting heavy metals in welding fume samples and to compare performances of two pretreatment methods, the acid extraction and the microwave digestion, in extracting heavy metals contained in the real workplace samples from various welding jobs including arc, argon, and carbon dioxide. A total of 25 analytical chemists in the industrial hygiene laboratories participating the quality control program directed by the Korea Industrial Safety Corporation were interviewed by telephone. For the purpose of comparing performance of extracting heavy metals from real workplace samples, a total of 53 welders from 21 workplaces located in Anyang, Uiwang, and Kunpo areas were sampled from the period of March 22, 1999 to April 20, 1999. It was found that the most frequently adopted method for samples from the quality control program was the acid extraction method(40%) followed by the NIOSH 7300 method(36%). The NIOSH method, however, was the dominant method(36%) for samples from workplace followed by the acid extraction method(28%). In this study, two extraction methods, the acid extraction and the microwave digestion, were compared in terms of recovery rate, accuracy, and precision for both manganese and chromium. Both methods produced comparable results for the samples prepared for the quality control program. In contrast, concentrations of two heavy metals determined from real workplace samples pretreated with the microwave digestion method were statis tically significantly higher, manganese(166%) and chromium (200%), than those of utilizing the acid extraction method. These findings were consistent regardless of types of welding techniques used. The results of this study clearly show the importance of verifying the analytical performances of extraction methods for heavy metals not only for the samples from the quality control program but also from the real world samples collected from welding jobs.

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Event Sentence Extraction for Online Trend Analysis (온라인 동향 분석을 위한 이벤트 문장 추출 방안)

  • Yun, Bo-Hyun
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.9-15
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    • 2012
  • A conventional event sentence extraction research doesn't learn the 3W features in the learning step and applies the rule on whether the 3W feature exists in the extraction step. This paper presents a sentence weight based event sentence extraction method that calculates the weight of the 3W features in the learning step and applies the weight of the 3W features in the extraction step. In the experimental result, we show that top 30% features by the $TF{\times}IDF$ weighting method is good in the feature filtering. In the real estate domain of the public issue, the performance of sentence weight based event sentence extraction method is improved by who and when of 3W features. Moreover, In the real estate domain of the public issue, the sentence weight based event sentence extraction method is better than the other machine learning based extraction method.

Changes in Extraction Efficiency of Pine Needles depending on Extraction Method and the Condition (추출 방법과 조건에 따른 소나무 지엽 추출효율 변화)

  • Kim, Dong Sung;Kim, Hyung Min;Sung, Yong Joo;Kang, Seog Goo;Kang, Ho-Yang;Lee, Jun-Woo;Kim, Se Bin;Park, Gwan-Soo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.1
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    • pp.93-99
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    • 2016
  • The extraction efficiency depending on the extracting methods and the conditions of extraction was investigated. The common steam extraction was compared to the distillation extraction method. The effects of the samples size and the extraction time on the extract yield were also investigated by using UV-Vis spectrophotometer. One of the functional components of pine needle extract as the natural phenol base components were detected by the UV-VIS at around 235 nm wavelength range. The absorbance intensity at around 235 nm wavelength of the pine needle extract was used as the indicator of the extraction efficiency in this experiment. The distillation extraction showed the higher extract yield than the steam extraction. The grinding treatment of pine needles also resulted in the better extract performance, but the severe grinding showed a little decrease in the extract yield especially in case of the distillation extraction method. More than half of the extract was collected at the first stage of the extraction, that was the first 15 minutes in the total 60 minutes extraction.

Quality and characteristics of fermented ginseng seed oil based on bacterial strain and extraction method

  • Lee, Myung-Hee;Rhee, Young-Kyoung;Choi, Sang-Yoon;Cho, Chang-Won;Hong, Hee-Do;Kim, Kyung-Tack
    • Journal of Ginseng Research
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    • v.41 no.3
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    • pp.428-433
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    • 2017
  • Background: In this study, the fermentation of ginseng seeds was hypothesized to produce useful physiologically-active substances, similar to that observed for fermented ginseng root. Ginseng seed was fermented using Bacillus, Pediococcus, and Lactobacillus strains to extract ginseng seed oil, and the extraction yield, color, and quantity of phenolic compounds, fatty acids, and phytosterol were then analyzed. Methods: The ginseng seed was fermented inoculating 1% of each strain on sterilized ginseng seeds and incubating the seeds at $30^{\circ}C$ for 24 h. Oil was extracted from the fermented ginseng seeds using compression extraction, solvent extraction, and supercritical fluid extraction. Results and Conclusion: The color of the fermented ginseng seed oil did not differ greatly according to the fermentation or extraction method. The highest phenolic compound content recovered with the use of supercritical fluid extraction combined with fermentation using the Bacillus subtilis Korea Food Research Institute (KFRI) 1127 strain. The fatty acid composition did not differ greatly according to fermentation strain and extraction method. The phytosterol content of ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method was highest at 983.58 mg/100 g. Therefore, our results suggested that the ginseng seed oil fermented with Bacillus subtilis KFRI 1127 and extracted using the supercritical fluid method can yield a higher content of bioactive ingredients, such as phenolics, and phytosterols, without impacting the color or fatty acid composition of the product.

Quantitative Extraction Analysis of Brominated Flame Retardant Substances Using Supercritical-Fluid Method for Environmental Assessment (초임계추출법을 이용한 브롬계 난연제 화합물 환경성 평가 추출효율 분석 연구)

  • Oh, Min-Kyung;Yoon, Sang-Hwa;Lee, Young-Kwan;Han, Jae-Sung;Won, Sung-Ho;Nam, Jae-Do
    • Polymer(Korea)
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    • v.32 no.1
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    • pp.13-18
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    • 2008
  • For the evaluation of brominated flame retardants included in polymeric electronic devices, we investigated the extraction methods and solvent systems for four different types of polymers of PC (polycarbonate), PP (polyropylene), PET (poly(ethylene terephthalate)) and PBT (poly(butylene terephthalate)) using different solvent systems of hexane/acetone, THF, toluene, and THF/toluene. In order to compare the extraction efficiency of different methods and solvent systems, the deca-BDE (decabromo diphenyl ether) flame retardant was included in PC, PP, PET and PBT systems and subsequently extracted by soxhlet, ultrasonic, accelerated solvent, microwave and supercritical fluid extraction methods. The amount of the extracted flame retardant was monitored to evaluate the extraction efficiency. The ultrasonic extraction method was found not to be acceptable as an extraction method for the polymer systems mainly due to a low salvation efficiency of the organic solvents. Soxhlet, accelerated solvent and microwave extraction methods exhibited over 80% of extraction efficiency for toluene. The supercritical fluid extraction method, which has been used as an extraction method for flame retardants in polymers, showed the extraction efficiencies of ca. 100% for PC and PP in the optimal extraction conditions of $60^{\circ}C$ and 120 bar.