• 제목/요약/키워드: KCI

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Pectin Transeminase produced by Aspergillus niger and two yeast species. (Aspergillus niger와 이종의 Yeast에 의한 Pectin Transeliminase의 생성 및 그 특성)

  • 민경희;이영자;김치경
    • Microbiology and Biotechnology Letters
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    • v.8 no.4
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    • pp.229-235
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    • 1980
  • Pectin transeliminase (PTE) was produced by Saccharomyces cerevisiae, Schizosaccharomyces pombe 4683, and Aspergillus niger in the media containing 2% pectin and examined for its characteristics. The Production of the enzyme was higher by Asp. niger than by the two yeast strains, showing that the PTE activity was proportional to reducing power. The enzyme was proved to reduce pectin and produce 4, 5- unsaturated galacturonic acid. The optimum activity of the PTE was found to be at pH 6.0 and $50^{\circ}C$. The activities of these enzyme were stable below $50^{\circ}C$ but decreased at the higher temperature. Substrate inhibition of the PTE activities was appeared at high concentrations of pectin. Those PTE activities were increased under 0.6M of KCI and NaCI, but that maximal activities at the concentration of 0.2M MgC $l_2$.

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A Study on the Correlation between the Appearance Frequency of Author Keyword and the Number of Citation in the Humanities and Social Science Journal Articles of the Korea Citation Index (KCI) (인문학 및 사회과학 분야 국내 학술논문의 저자키워드 출현빈도와 피인용횟수의 상관관계 연구)

  • Ko, Young Man;Song, Min-Sun;Kim, Bee-Yeon;Min, Hye-Ryoung
    • Journal of the Korean Society for information Management
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    • v.30 no.2
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    • pp.227-243
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    • 2013
  • The purpose of this study is to verify the correlation between the appearance frequency of author keyword and the number of citation in journal articles. In this study, we were trying to develop a methodology that can select the term having semantic relation with other terms and higher utilization to build a structured scientific glossary. In order to achieve this purpose, we analyzed the number of citation and the author keyword of the humanities and social science journal articles of the Korea Citation Index (KCI) from 2007 to 2011. This study found a correlation between appearance frequency of author keyword and the number of citation of the journal articles, with higher appearance frequency of author keyword of the journal articles being more cited.

An Analysis of the Shear Strength of Reinforced Concrete Beams with Recycled Coarse Aggregates (순환굵은골재 철근 콘크리트 보의 전단강도 분석)

  • Ji, Sang-Kyu;Yun, Hyun-Do;Song, Seon-Hwa;Choi, Ki-Sun;You, Young-Chan;Kim, Keung-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.851-854
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    • 2008
  • Using the recycled aggregate not only saves landfill space but also reduces the demand for extraction of natural raw material for new construction activity. However few investigations have been carried out to study the shear behaviors of RC beams with recycled aggregates such as low absorption of recycled aggregate and full-scale specimens. In this study, six reinforced concrete beams were tested to evaluate the effects of shear strength, and shear behavior on the replacement level (0, 30, 60, and 100%) of recycled coarse aggregate and different amounts of shear reinforcement. The results showed that the beams with recycled coarse aggregates present the similar shear strength and deflections as the beam with natural aggregate on an equal amount of shear reinforcement. the reinforced concrete beams with recycled coarse aggregates present the Influence of shear span-to-depth ratio, effective depth, tension reinforcement ratio and compressive strength as the beams with natural aggregate. Shear strength were compared with the provisions in current code (KCI2007) and the equation proposed by Zsutty. The KCI equations were conservative and subsequently can be used for the shear design of recycled aggregate concrete beam.

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The Research Collaboration Pattern of Library and Information Science Field in Korea: Application of Collaboration Indices (국내 문헌정보학 분야의 연구협업 패턴에 관한 연구: - 협업지수의 적용 -)

  • Park, Ji-Hong;Heo, Ji-Young
    • Journal of Korean Library and Information Science Society
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    • v.48 no.1
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    • pp.191-206
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    • 2017
  • The purpose of this study is to compare the characteristics of research collaborations in the field of LIS. While there are several studies under the unit of analysis of country, there are only a few studies under the unit of analysis of institution in LIS field. For this analysis, we selected eight journals in the KCI (Korea Citation Index) web site, which correspond to the field of LIS through subject classification. The collaborative indices, Collaborative Coefficient, Co-Authorship Index, Local Collaborative Index (LCI), Domestic Collaborative Index (DCI) allowed us to comparatively analyze institutional collaboration patterns in LIS field. In the case of Chung-Ang University, Yonsei University, and Ewha Womans University, collaborative research among professors, graduate students, and professors reflected the fact that collaborations among universities are often performed with professors. In the case of KISTI, which showed a very high index value, the characteristics of project-based research are reflected in the research collaboration pattern.

The Effect of Three kinds of Coptis Rhizoma on the Contraction of Isolated Rat Tracheal Smooth Muscle (삼종(三種) 황연류(黃連類)의 기관지(氣管支) 평활근(平滑筋) 이완효과(弛緩效果)에 관(關)한 연구(硏究))

  • Suh, Young-Chel;Lim, Seong-Woo;Shin, Gil-Cho;Lee, Won-Chul
    • Korean Journal of Oriental Medicine
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    • v.2 no.1
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    • pp.236-254
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    • 1996
  • This study was carried out to investigate the tracheal muscle relaxation of water extracts of three kinds of Coptis rhizoma and also compare their effects with berberine and palmatine, which are the important alkaloid components of Coptis rhizoma, in isolated rat tracheal smooth muscle. As a result Coptis chinenis showed significant tracheal muscle relaxation on KCI-induced contraction and more markedly on carbachol-induced contraction in dose-dependent manner. Coptis japoinin exhibited also tracheal muscle relaxation on both contraction with slightly weaker activities than those of Coptis chinensts. The activities of the root hair of Coptis chinensis were the most weakest in three rhizomas. Berberine and palmatine had strong tracheal muscle relaxation, especially, on carbachol-induced contraction, however, their activities on KCI-induced contraction were weaker than that of Coptis chinenis. The inhibitory effects of three kinds of Coptis rhizoma on the contraction by KCI and carbachol were investigated to explain the process of their tracheal muscle relaxation. All rhizomas inhibited the contraction by both agents, among them, Coptis japonica showed the most significant effect, so indicating that the tracheal muscle relaxation of Coptis rhizoma may be concerned with the blocking of muscarine receptor and $Ca^{2+}$channel.

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Shear Performance of Full-scale Reinforced Concrete Beams with Recycled Fine Aggregates (순환잔골재의 치환율에 따른 철근콘크리트 보의 전단성능)

  • Ji, Sang-Kyu;Song, Seon-Hwa;Yun, Hyun-Do;Choi, Ki-Sun;You, Young-Chan;Kim, Keung-Hwan
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.205-208
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    • 2008
  • Using the recycled aggregate can reduces the landfill space, the demand for natural raw material for new construction. Some investigations have been carried out to study the shear behaviors of RC beams with recycled aggregates. But these have some limitation due to the use of low quality recycled aggregates and small-scale specimens in the laboratory. In this study, four full-scaled RC beams were tested to evaluate the effects of replacement level (0,30, 60, and 100%) of recycled fine aggregate on shear behavior of RC beams. The results showed that the beams with recycled fine aggregates show similar crack pattern and failure mode compared with the beam with natural aggregate. Also, the beams with recycled fine aggregates present the similar shear strength except the one with the replacement level of 100% recycled fine aggregates. Shear strength were compared with the provisions in current code (KCI2007) and the equation proposed by Zsutty. The KCI equations were conservative and subsequently can be used for the shear design of recycled aggregate concrete beam.

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Evaluation of Shrinkage and Creep Behavior of Low-Heat Cement Concrete (저열 시멘트 콘크리트의 건조수축 및 크리프 거동 평가)

  • Mun, Jae-Sung;Yang, Keun-Hyeok;Kim, Si-Jun
    • Journal of the Korea Institute of Building Construction
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    • v.16 no.4
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    • pp.305-311
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    • 2016
  • This study examined the long-term inelastic characteristics, including unrestrained shrinkage and creep, of low-heat cement concrete under different ambient curing temperatures. To achieve the designed compressive strength of 42MPa, water-to-binder ratios were selected to be 27.5, 30, and 32.5% for curing temperatures of 5, 20, and $40^{\circ}C$, respectively. Test results showed that the shrinkage strains of concrete mixtures tended to decrease with the decrease in curing temperature because of the delayed evaporation of internal capillary and gel waters. Meanwhile, creep strains were higher in concrete specimens under lower curing temperature due to the occurrence of the transition temperature creep. The design models of KCI provision gave better accuracy in comparison with test results than those of ACI 209, although a correction factor for low-heat cement needs to be established in the KCI provision.

An Study on Privacy Policy Research Trend: Focused on KCI Published (개인정보보호정책에 관한 연구동향 고찰: KCI등재지를 중심으로)

  • Bok, Jun-Young
    • Journal of Digital Convergence
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    • v.18 no.4
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    • pp.81-89
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    • 2020
  • Since the Korean privacy policy was legalized in 2011, the related academical researches have been lasted in various fields. Upcoming so-called 3 data laws would be implemented, it is meaningful to review privacy policy studies for exploring future research direction. For this purpose, the total of 146 journals from 2011 to 2019 were reviewed by the content analysis following as research subjects, methodologies and constructions of studies. As results, the numbers of the researches have been conducted on protection policies themselves for improvement, comparing with other countries' policies and also digital finance information protection were deeply discussed. Some of technology based protection applications were experimented and suggested. The major research characteristics was mainly focused on case analysis and criminal laws and policies were developed as protection contingencies. However, most research objects were focused on the protection regulations, not deregulation, therefore, researchers in future study need to explore more digital industry-centric tasks which are practically applied in safer ways. Further, social agreement in using private information will be an essential to prevent indiscriminate use.

The Load Transfer Performance of Post-tension Anchorage with 2,400 MPa Strands (2,400 MPa 강연선용 포스트텐션 정착구의 하중전달성능)

  • Kim, Sun-Woo;Lho, Byeong-Cheol;Lim, Jung-Hoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.22 no.6
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    • pp.63-71
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    • 2018
  • Strands with ultimate strength of 2,400 MPa was developed and applied in the KCI Code and the KS standard. A high-strength prestressed strand to be applied to a structure, a suitable anchorage system should be used together. Recently, a post tension anchorage for 2,400 MPa strands was developed. but there is not much research on performance evaluation. Therefore, in this study, structural analysis of local zone with 9 strands, 15 strands, and 19 strands anchorage were investigated respectively, which are most widely used for post tensioning anchorages with 2,400 MPa strands, according to PTI anchorage zone design method, and Load transfer performance from ETAG013 and/or KCI-PS101 was evaluated. Furthermore, the adequacy of the test was also analyzed by nonlinear numerical analysis. As results, the anchorages with 2,400 MPa strands satisfied the structural performance of the local area and satisfied the load transfer performance condition.

Topic Modeling on Research Trends of Industry 4.0 Using Text Mining (텍스트 마이닝을 이용한 4차 산업 연구 동향 토픽 모델링)

  • Cho, Kyoung Won;Woo, Young Woon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.7
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    • pp.764-770
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    • 2019
  • In this research, text mining techniques were used to analyze the papers related to the "4th Industry". In order to analyze the papers, total of 685 papers were collected by searching with the keyword "4th industry" in Korea Journal Index(KCI) from 2016 to 2019. We used Python-based web scraping program to collect papers and use topic modeling techniques based on LDA algorithm implemented in R language for data analysis. As a result of perplexity analysis on the collected papers, nine topics were determined optimally and nine representative topics of the collected papers were extracted using the Gibbs sampling method. As a result, it was confirmed that artificial intelligence, big data, Internet of things(IoT), digital, network and so on have emerged as the major technologies, and it was confirmed that research has been conducted on the changes due to the major technologies in various fields related to the 4th industry such as industry, government, education field, and job.