• Title/Summary/Keyword: 분별

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Comparison of Characteristics of Acid-catalyzed Hydrothermal Fractionation for Production of Hemicellulose Hydrolyzate from Agricultural Residues (농경잔류물로부터 헤미셀룰로오스 가수분해물 생산을 위한 산촉매 열수 분별공정의 특성 비교)

  • Hwang, Jong Seo;Oh, Kyeong Keun;Yoo, Kyung Seun
    • Korean Chemical Engineering Research
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    • v.60 no.3
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    • pp.414-422
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    • 2022
  • The objective of this work was to investigate the feasibility of acid-catalyzed hydrothermal fractionation for maximum solubilization of the hemicellulosic portion of two typical agricultural residues. The fractionation conditions converted into combined reaction severity (CS) in the range of 1.2-2.9 was used to establish a simple reaction criteria at glance. The hemicellulosic sugar yield of 56.6% was shown when rice straw was fractionated at the conditions at the conditions; 160 ℃ of temperature 0.75% (w/v) of H2SO4, 20 min of reaction time, 1:15 solid/liquid ratio. The hemicellulosic sugar yield of 83.0%, however, was achieved when barley straw was fractionated at the conditions at the conditions; 150 ℃ of temperature 0.75% (w/v) of H2SO4, and 15 min of reaction time, 1:10 solid/liquid ratio. For barley straw, acid-catalyzed hydrothermal fractionation could be effectively performed. After the fractionation process, the remaining fractionated solids were 48.5% and 57.5% from raw rice and barley straws, respectively. The XMG contents in the solid residues decreased from 17.3% and 17.6% to 6.0% and 2.6%, which corresponded to 16.7% and 8.5% on the basis of the raw straws, respectively. In another way, only 5.6% of cellulose and 8.5% of XMG were lost due to excessive decomposition during the acid-catalyzed hydrothermal fractionation of barley straw, compared to cellulose and XMG losses of 6.4% and 26.6% in rice straw. Hemicellulosic sugars from the rice straw were considered more over-decomposed due to the somewhat higher reaction severity at the acid-catalyzed hydrothermal fractionation.

Decreasing Particle Size of (+)-Dihydromyricetin Using Hydrophilic Polymer in Fractional Precipitation (분별침전에서 친수성 고분자 물질을 이용한 (+)-dihydromyricetin의 입자크기 감소)

  • Ji, Seong Bin;Kim, Jin-Hyun
    • Korean Chemical Engineering Research
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    • v.56 no.3
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    • pp.370-375
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    • 2018
  • In this study, we have applied fractional precipitation with hydrophilic polymer in order to decrease the particle size of the (+)-dihydromyricetin from plant materials. When compared with the case where no hydrophilic polymer was employed, the addition of hydrophilic polymer in fractional precipitation resulted in a considerable decrease in the size of the (+)-dihydromyricetin precipitate. Among the polymers used, HPMC 2910 was the most effective for inhibition of precipitate growth. A polymer concentration of 0.1% (w/v) yielded the smallest particle size. The particle size was reduced by ~40% compared to control. In addition, the precipitate size was inversely correlated with the absolute value of the zeta potential of the suspension with polymer.

An Improved Homonym Disambiguation Model based on Bayes Theory (Bayes 정리에 기반한 개선된 동형이의어 분별 모델)

  • Lee, Wang-Woo;Lee, Jae-Hong;Lee, Soo-Dong;Ock, Cheol-Young;Kim, Hyun-Gee
    • Annual Conference on Human and Language Technology
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    • 2001.10d
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    • pp.465-471
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    • 2001
  • 본 연구에서는 동형이의어 분별을 위하여 허정(2000)이 제시한 "사전 뜻풀이말에서 추출한 의미정보에 기반한 동형이의어 중의성 해결 시스템" 이 가지는 문제점과 향후 연구과제로 제시한 문제들을 개선하기 위하여 Bayes 정리에 기반한 동형이의어 분별 모델을 제안한다. 의미 분별된 사전 뜻풀이말 코퍼스에서 동형이의어를 포함하고 있는 뜻풀이말을 구성하는 체언류(보통명사), 용언류(형용사, 동사) 및 부사류(부사)를 의미 정보로 추출한다. 동형이의어의 의미별 사전 출현 빈도수가 비교적 균등한 기존 9개의 동형이의어 명사를 대상으로 실험하여 비교하였고, 새로 7개의 동형이의어 용언(형용사, 동사)을 추가하여 실험하였다. 9개의 동형이의어 명사를 대상으로 한 내부 실험에서 평균 99.37% 정확률을 보였으며 1개의 동형이의어 용언을 대상으로 한 내부 실험에서 평균 99.53% 정확률을 보였다. 외부 실험은 국어 정보베이스와 ETRI 코퍼스를 이용하여 9개의 동형이의어 명사를 대상으로 평균 84.42% 정확률과 세종계획의 350만 어절 규모의 외부 코퍼스를 이용하여 7개의 동형이의어 용언을 대상으로 평균 70.81%의 정확률을 보였다.

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Decreasing Particle Size of Paclitaxel Using Polymer in Fractional Precipitation Process (고분자물질을 이용한 분별침전 공정에서 파클리탁셀의 입자크기 감소)

  • Kim, Min Jae;Kim, Jin-Hyun
    • Korean Chemical Engineering Research
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    • v.54 no.2
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    • pp.278-283
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    • 2016
  • In this study, we have for the first time applied fractional precipitation with hydrophilic polymer in order to decrease the particle size of the anticancer agent paclitaxel from plant cell cultures. When compared with the case where no hydrophilic polymer was employed, the addition of hydrophilic polymer in fractional precipitation resulted in a decrease in the size of the paclitaxel precipitate. Among the polymers used, HPMC 2910 was the most effective for inhibition of precipitate growth. A polymer concentration of 0.2% (w/v) obtained the smallest particle size. The particle size was reduced by ~35% compared to control. In addition, the precipitate size was inversely correlated with the absolute value of the zeta potential.

On the Filtering of Hangul character Element with the Spatial Positioning Modulation (공간 위치 변조에 의한 한글자소의 필터링)

  • 강대수;진용옥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.9
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    • pp.1029-1039
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    • 1992
  • This paper presents the filtering method which is processed on the frequency domain among Hangul character recognition methods. It is processed the Hangul character parrern with spatial positioning modulation and mapped the Hangul character element which have spatial position variant feature onto frequency domain, at this time, normalized spatial position and so normalized the character size in frequency domain. And it is grouped the Hangul character element according to the generating position and set the standard pattern, and used each standard character element pattern with character element filter and filtering the character pattern of Hangul character, it is derived the normalized cross correlation function and the coherence function led to the filtering results, and calculated classification threshold.

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Decrease in the Particle Size of Paclitaxel by Increased Surface Area Fractional Precipitation Process Using Hydrophilic Polymer (표면적이 증가된 분별침전에서 친수성 고분자물질을 이용한 paclitaxel의 입자 크기 감소)

  • Lim, Yong Kyu;Kim, Jin-Hyun
    • Microbiology and Biotechnology Letters
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    • v.43 no.4
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    • pp.343-349
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    • 2015
  • In this study, we applied an increased surface area fractional precipitation with hydrophilic polymer for decreasing the particle size of the anticancer agent paclitaxel from plant cell cultures. The addition of polymer resulted in a considerable decrease in the size of the paclitaxel precipitate. Among the polymers (HPMC 2910, PVP-K90, PVA) used, PVP-K90 was the most effective for the inhibition of precipitate growth. When PVP-K90 (0.2%, w/v) was used, the paclitaxel particles were four to five times smaller, having less than a $20{\mu}m$ radius, than those obtained in the absence of the polymer. In addition, the precipitate size was inversely correlated with the absolute value of zeta potential.

Effect of Zeta Potential on Fractional Precipitation for the Purification of Paclitaxel from Plant Cell Cultures of Taxus chinensis (주목 식물세포(Taxus chinensis) 배양 유래 Paclitaxel 정제를 위한 분별침전에서 제타전위 영향)

  • Ryu, Heung Kon;Kim, Jin-Hyun
    • Microbiology and Biotechnology Letters
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    • v.42 no.2
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    • pp.114-120
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    • 2014
  • This study evaluated the effect of the zeta potential of silica-alumina on the behavior, in terms of purity, yield, fractional precipitation time, precipitate shape, size of fractional precipitation in the increased surface area, and the fractional precipitation process, for the purification of paclitaxel. As the zeta potential value of silica-alumina increased, the yield of paclitaxel concurrently increased while the precipitation time decreased. The use of alumina with the highest value of the zeta potential (+35.41 mV) as a surface area-increasing material dramatically reduced the precipitation time by 12 h compared with the results of the control. On the other hand, the purity of paclitaxel had almost no effect on changes in the zeta potential of silica-alumina. In addition, the precipitate size was inversely correlated with the absolute value of the zeta potential.

Economic Feasibility Assessment for the Interior Materials Selective Dismantling System Promotion in Buildings (건축물 분별해체 제도 활성화를 위한 경제적 효용성 평가)

  • Ji-Sun Park;Kyung-Pil Jang;Tae-Hyeob Song
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.3
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    • pp.251-259
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    • 2023
  • In this study, as a foundational research aimed at promoting the efficient recycling and environmentally friendly disposal of construction waste through the activation of a selective dismantling system, our primary objective was to analyze the economic feasibility of implementing selective dismantling. To achieve this, we conducted an assessment on a 5-story residential building with a construction area of 2,400 m2 as a case study. When considering the additional cost of dismantling construction ① the reduction in waste disposal costs due to decreased mixed waste, ② and the potential revenue from recycling through the separation and sorting of waste materials, and ③ we were able to comprehensively confirm that there is an expected cost-saving effect totaling 34,727,000 KRW when compared to conventional demolition methods.

Salient Region Detection by Distinctive Color Channel Selection (분별력 있는 색상 채널의 선택을 통한 두드러진 영역 검출)

  • Chae, Young-Soo;Kim, Hyun-Cheol;Kim, Whoi-Yul
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2010.07a
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    • pp.428-431
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    • 2010
  • 본 논문에서는 분별력 있는 색상 채널 선택을 통한 두드러진 영역 검출 방법을 제안한다. 제안하는 방법에서는 우선 분별력 있는 색상 채널의 선택을 위해 입력영상을 10개의 색상 채널로 변경하고, 각 채널을 NxN 블록으로 나눈다. 그리고 각 채널에서 나누어진 N 블록을 외각 블록, 중앙 블록으로 선정하고 중앙-외각 블록간의 대비와 외각 블록의 표준편차 정보를 이용하여 색상 채널 경쟁을 한다. 색상 채널 경쟁을 통해 선별된 K개의 색상 채널을 이용하여 특징맵을 만들고 이를 조합하여 두드러진 맵을 얻는다. 실험에서는 제안된 방법을 총 1000장의 자연 영상에 적용하여 성능을 평가하였으며, 83%의 평균 정확도를 보임으로써 기존 방법들보다 성능이 뛰어남을 확인하였다.

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