• Title/Summary/Keyword: Natural Science and Engineering

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Boolean Formulation of Korean Natural Language Queries Using Syntactic Analysis (구문 분석에 기반한 자연어 질의로부터의 불리언 질의 생성)

  • Park, Mi-Hwa;Won, Hyung-Suk;Lee, Won-Il;Lee, Geun-Bae
    • Annual Conference on Human and Language Technology
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    • 1998.10c
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    • pp.73-80
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    • 1998
  • 본 연구는 자연어 질의의 형태 및 구문 정보를 바탕으로 불리언 질의를 생성하는데 그 목적을 둔다. 일반적으로 대부분의 상용정보검색시스템은 입력형식을 검색성능이 종은 불리언 형태로 하고 있으나, 일반 사용자는 자신이 원하는 정보를 불리언 형태로 표현하는데 익숙하지 않다. 그러므로 본 정보검색시스템은 자연어 질의를 기본 입력형태로 하여 사용자의 편의성을 높이고, 이 질의를 범주문법에 기반한 구문분석 결과에 의해 복합명사를 고려한 불리언 형태로 변환하여 검색을 수행함으로써 시스템의 검색 성능의 향상을 도모하였다. 정보검색 실험용 데이터 모음인 KTSET2.0으로 실험한 결과 본 논문에서 제안한 자연어 질의로부터 자동 생성된 불리언 질의의 검객성능이 KTSET2.0에서 제공하는 수동으로 추출한 불리언 질의보다 8% 더 우수한 성능을 보였고, 기존 자연어질의 시스템이 수용해온 방법인 형태소 분석을 거쳐 불용어를 제거한 후 Vector 모델을 적용하여 검색을 수행한 경우보다는 23% 더 나은 성능을 보였다.

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Spoilage Lactic Acid Bacteria in the Brewing Industry

  • Xu, Zhenbo;Luo, Yuting;Mao, Yuzhu;Peng, Ruixin;Chen, Jinxuan;Soteyome, Thanapop;Bai, Caiying;Chen, Ling;Liang, Yi;Su, Jianyu;Wang, Kan;Liu, Junyan;Kjellerup, Birthe V.
    • Journal of Microbiology and Biotechnology
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    • v.30 no.7
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    • pp.955-961
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    • 2020
  • Lactic acid bacteria (LAB) have caused many microbiological incidents in the brewing industry, resulting in severe economic loss. Meanwhile, traditional culturing method for detecting LAB are time-consuming for brewers. The present review introduces LAB as spoilage microbes in daily life, with focus on LAB in the brewing industry, targeting at the spoilage mechanism of LAB in brewing industry including the special metabolisms, the exist of the viable but nonculturable (VBNC) state and the hop resistance. At the same time, this review compares the traditional and novel rapid detection methods for these microorganisms which may provide innovative control and detection strategies for preventing alcoholic beverage spoilage, such as improvement of microbiological quality control using advanced culture media or different isothermal amplification methods.

Fabrication of Antimicrobial Wound Dressings Using Silver-Citrate Nanorods and Analysis of Their Wound-Healing Efficacy

  • Park, Yong Jin;Jeong, Jisu;Kim, Jae Seok;Choi, Dong Soo;Cho, Goang-Won;Park, Jin Seong;Lim, Jong Kuk
    • Journal of Integrative Natural Science
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    • v.12 no.2
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    • pp.47-57
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    • 2019
  • Staphylococcus epidermidis is well-known not only as an innocuous normal flora species commonly isolated from human skin, but also as an important bacterial species to keep skin healthy, because this species can protect the human skin from pathogenic microorganisms. However, S. epidermidis turns into a potential pathogen in damaged skin, because these bacteria can easily form a biofilm on the wound area and provide antimicrobial resistance to other microorganisms embedded in the biofilm. Thus, it is important to kill S. epidermidis in the early stage of wound treatment and block the formation of biofilms in advance. In the present study, hydrogel wound dressings were fabricated using polyvinyl alcohol/polyethylene glycol containing silver citrate nanorods, which have been proven to have strong antimicrobial activity, especially against S. epidermidis, and their wound-healing efficacy was investigated in vivo using a rat experiment.

Improved Production of Curdlan with Concentrated Cells of Agrobacterium sp.

  • Jung, Dae-Young;Cho, Young-Su;Chung, Chung-Han;Jung, Dai-Il;Kim, Kwang;Lee, Jin-Woo
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.2
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    • pp.107-111
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    • 2001
  • The addition of a limited concentration of yeast extract to a minimal salt medium (MSM) enhanced cell growth and increased the production of curdlan whereas nitrogen-limitation was found to be essential for the higher production of curdlan by Agrobacterium sp. ATCC 31749. As the amount of the inoculum increased, the cell growth as well as the production of curdlan also increased in the MSM without a nitrogen source. The cell growth and production of curdlan increased as the initial pH of the medium decreased as low as 5.0. The conversion rate and concentration of curdlan from 2% (w/v) glucose in the MSM with concentrated cells under nitrogen deletion was 67% and 13.4 g/L, respectively. The highest conversion rate of curdlan under the conditions optimized in this study was 71% when the glucose concentrations was 1% (w/v).

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Iron-loaded Natural Clay as Heterogeneous Catalyst for Fenton-like Discoloration of Dyeing Wastewater

  • Xu, Huan-Yan;Ha, Xiu-Lan;Wu, Ze;Shan, Lian-Wei;Zhang, Wei-Dong
    • Bulletin of the Korean Chemical Society
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    • v.30 no.10
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    • pp.2249-2252
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    • 2009
  • The clay-based Fe-bearing catalyst was successfully prepared through ion-exchange reaction and applied as heterogeneous catalyst for discoloration of acid fuchsine (AF) in an aqueous solution by Fenton-like reaction. Experimental results demonstrated that the AF discoloration ratios increased by increasing Fe-loaded clay dosage and initial $H_2O_2$ concentration, and by decreasing the pH, respectively. The lower the initial AF concentration, the shorter the reaction time needed to achieve complete discoloration of AF. Comparative studies indicated that AF discoloration ratios were much higher in presence of Fe-loaded clay and $H_2O_2$ than those in presence of $H_2O_2$, raw natural clay or Fe-loaded clay only and raw natural clay and $H_2O_2$ jointly. After AF discoloration, there existed no new phases in the clay samples detected by XRD and no change in the clay crystal morphology observed by SEM. A mechanism proposed suggested adsorption and Fenton-like reaction were responsible for discoloration of AF.

Habitat Quality Valuation Using InVEST Model in Jeju Island (InVEST 모델을 이용한 서식처 가치 평가 - 제주도를 중심으로 -)

  • Kim, Teayeon;Song, Cholho;Lee, Woo-Kyun;Kim, Moonil;Lim, Chul-Hee;Jeon, Seong Woo;Kim, Joonsoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.18 no.5
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    • pp.1-11
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    • 2015
  • Jeju Island is managed intensively in terms of environmental and ecological aspect because of its extraordinary ecosystem types comprising numerous rare, protected flora and fauna. To depict rapid change of habitat status in Jeju Island, the InVEST Habitat Quality model has been operated and compared analytically with the Eco-Natural map. The Habitat Quality map of Jeju Island is turned out to have similar inclination with Eco-Natural map. We compared the average habitat quality value in each Eco-natural map class in Jeju Island and the habitat quality value of first second third grade and non-included area decreased as 0.95 0.76, 0.53 and 0.37 in eco natural map respectively. Compared to biodiversity map based on biological investigation, the result of the InVEST habitat quality model can be simply obtained by land cover map with threat and sensitivity data. Further studies are needed to make explicit coefficients for Jeju Island and Korean peninsula, then the Habitat Quality model could be applied to past and future scenarios to analyze extent of habitat degradation in time series to help decision makers.

Increase of isoflavones in soybean callus by Agrobacterium-mediated transformation

  • Jiang, Nan;Jeon, Eun-Hee;Pak, Jung-Hun;Ha, Tae-Joung;Baek, In-Youl;Jung, Woo-Suk;Lee, Jai-Heon;Kim, Doh-Hoon;Choi, Hong-Kyu;Cui, Zheng;Chung, Young-Soo
    • Plant Biotechnology Reports
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    • v.4 no.4
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    • pp.253-260
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    • 2010
  • Plant secondary metabolites have always been a focus of study due to their important roles in human medicine and nutrition. We transferred the isoflavone synthase (IFS) gene into soybean [Glycine max (L.) Merr.] using the Agrobacterium-mediated transformation method in an attempt to produce transformed soybean plants which produced increased levels of the secondary metabolite, isoflavone. Although the trial to produce transgenic plant failed due to unestablished hygromycin selection, transformed callus cell lines were obtained. The induction rate and degree of callus were similar among the three cultivars tested, but light illumination positively influenced the frequency of callus formation, resulting in a callus induction rate of 74% for Kwangan, 67% for Sojin, and 73% for Duyou. Following seven to eight subcultures on selection media, the isoflavone content of the transformed callus lines were analyzed by high-performance liquid chromatography. The total amount of isoflavone in the transformed callus cell lines was three- to sixfold higher than that in control callus or seeds. Given the many positive effects of isoflavone on human health, it may be possible to adapt our transformed callus lines for industrialization through an alternative cell culture system to produce high concentrations of isoflavones.

Reconfiguration of the Power Mix in Korea with the Introduction of Shale Gas and Analysis of Its Impact on Atmospheric Environment (셰일가스 도입으로 인한 전원믹스 재구성 및 환경 영향 분석)

  • Choi, Narae;Yeo, Minjoo;Kim, Yong Pyo
    • Particle and aerosol research
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    • v.10 no.1
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    • pp.19-25
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    • 2014
  • In line with the expected price reduction of natural gas associated with the introduction of shale gas, it is expected that the optimal power mix for the electric power generation be changed. In this study, the reconfigured power mix is estimated with the varying natural gas price by using the Screening Curve Method (SCM). It is found that about 3% and 9% coal in the overall power mix is replaced with natural gas if the natural gas price falls 20% and 40% of the current price, respectively. It is also found that the reconfigured power mixes would provide the reduction of the emissions of air pollutants which are equivalent to 369 and 807 MUS$.

Molecular Characterization of a Novel Putative Partitivirus Infecting Cytospora sacchari, a Plant Pathogenic Fungus

  • Peyambari, Mahtab;Habibi, Mina Koohi;Fotouhifar, Khalil-Berdi;Dizadji, Akbar;Roossinck, Marilyn J.
    • The Plant Pathology Journal
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    • v.30 no.2
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    • pp.151-158
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    • 2014
  • Three double-stranded RNAs (dsRNAs), approximately 1.85, 1.65 and 1.27 kb in size, were detected in an isolate of Cytospora sacchari from Iran. Partial nucleotide sequence revealed a 1,284 bp segment containing one ORF that potentially encodes a 405 aa protein. This protein contains conserved motifs related to RNA dependent RNA polymerases (RdRp) that showed similarity to RdRps of partitiviruses. The results indicate that these dsRNAs represent a novel Partitivirus that we tentatively designate Cytospora sacchari partitivirus (CsPV). Treatment of the fungal strain by cyclohexamide and also hyphal tip culture had no effect on removing the putative virus. Phylogenetic analysis of putative RdRp of CsPV and other partitiviruses places CsPV as a member of the genus Partitivirus in the family Partitiviridae, and clustering with Aspergillus ochraceous virus 1.