• Title/Summary/Keyword: co occurrence

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Identification of Europium(III) Hydroxide Formation by Eu(III) Luminescence Specroscopy

  • 이병호;박영재;문희정
    • Bulletin of the Korean Chemical Society
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    • v.16 no.7
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    • pp.654-657
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    • 1995
  • A series of excitation spectra (7Fo→5Do transition) of Eu(Ⅲ) ion in aqueous solution ([Eu(Ⅲ)]=1.12 × 10-2 mol L-1; pH 1.0 to 7.0) were obtained under CO2 free atmosphere using a pulsed tunable dye laser system. The broad and low intensity spectra (peak maximum: 578.89 nm) showed that the trivalent ion (Eu3+) underwent a low degree of hydrolysis at pH below 6.0. Eu(Ⅲ) hydroxo complex formation seemed more significant at pH above 6.0, shown by the occurrence of intense new peak at 578.63 nm. The spectra of those solutions prepared in N2 atmosphere showed no signs of the presence of interfering carbonate species. The Eu(Ⅲ) hydroxo complex formation was not observed when complexation studies between Eu(Ⅲ) ion and weak organic acids (e.g. glutarate and diglycolate) were conducted at pH 6.0 or below.

Occurrence of sea lice, Caligus undulatus Shen and Li, 1959 (Copepoda: Siphonostomatoida: Caligidae) in plankton samples collected from Korea

  • Moon, Seong Yong;Park, Jong Sick
    • Journal of Species Research
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    • v.8 no.4
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    • pp.365-372
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    • 2019
  • We have conducted faunistic study of sea lice collected from marine plankton samples of western and southern coasts of Korea. These specimens were identified as Caligus undulatus Shen and Li, 1959, belonging to family Caligidae and order Siphonostomatoida with worldwide distribution. The range extension of C. undulatus is reported in addition to the previously known distributional range from the Northwest Pacific (China, Japan, and Korea), India, Brazil, and Mexico. This species can be distinguished from all previous reports with characteristics such as overall body proportions of both sexes, structure details of mouth appendages, armature of legs, and some variation in body size. The distributional range of C. undulatus is now given with its northern and south hemisphere limit being 40 to $10^{\circ}N$ in the Indo-Pacific and $30^{\circ}S$ in the Southwest Atlantic. This is the first record of its female occurring in Korea.

Word Sense Disambiguation Method Using Co-occurrence Information (공기정보를 이용한 단어 의미 중의성 해결 방안)

  • Park, Yo-Sep;Kim, Gyeong-Im;Park, Hyuk-Ro
    • Annual Conference on Human and Language Technology
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    • 2010.10a
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    • pp.177-178
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    • 2010
  • 단어 의미 중의성은 자연언어처리 분야에서의 주요 관심 분야이다. 한국어에서의 단어 의미 중의성 문제는 다른 언어에 비하여 연구가 미흡한 상태이다. 기존 연구에서는 빈도 수에 기반한 공기 정보 벡터를 이용한 방법에서 처리되지 못하는 경우가 발생하였다. 또한 사전에 기반한 상위어 추출 시에 정형화된 형태가 아닌 경우에 어려움이 발생하였다. 본 논문에서는 상호정보량을 추가하여 공기 정보 처리 과정 시에 발생하는 오류를 최소화 하였다. 또한 대상 명사의 상위어 추출 문제를 해결하기 위해 어휘 지식 베이스를 적용하였다.

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A Plant Breeder's View on H5N1

  • Kim, Soon-Kwon
    • Korean Journal of Breeding Science
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    • v.40 no.2
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    • pp.106-112
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    • 2008
  • International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

Analyzing Research Trends in Bioinformatics based on Comparison between Grey and White Bioinformatics Literatures (바이오인포매틱스 분야 회색문헌 및 백색문헌의 연구 동향 비교 분석)

  • Kim, Ye Eun;Kim, Jung Ju;Song, Min
    • Proceedings of the Korean Society for Information Management Conference
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    • 2013.08a
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    • pp.11-14
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    • 2013
  • 본 연구의 목적은 바이오인포매틱스 분야의 회색문헌과 백색문헌의 초록을 대상으로 단어 동시출현(word co-occurrence)네트워크 분석을 통해 해당 분야의 연구 동향을 비교 분석하고자 하였다. 이를 위해 2010년부터 2012년까지 발표된 회색문헌인 회의자료(proceeding)와 백색문헌인 학술논문(journal article)의 초록을 SCOPUS, IEEEXplore, Microsoft academic search에서 수집하였다. 단어 동시출현 네트워크를 분석한 결과 회색문헌의 주요 연구는 분석도구 및 방법으로, 백색문헌의 주요 연구는 바이오인포매틱스의 주요 연구대상인 유전자 발현, 단백질 서열 및 구조 등으로 나타났다.

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A Study on Micom Algorithm Design for Prevention of Serial Parallel Arc Accident (직병렬아크사고 예방을 위한 마이컴 알고리즘 설계에 관한 연구)

  • Choi, Jung-Kyu;Kwak, Dong-Kurl;Choi, Shin-Hyeong;Jung, Do-Young;Kim, Dae-Hwan
    • Proceedings of the KIPE Conference
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    • 2018.11a
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    • pp.9-11
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    • 2018
  • This paper studies on the development of an electric fire prevention system with the detection and alarm in case of parallel arc fault occurrence in low voltage distribution lines. The proposed detector has the characteristics of high speed operation responsibility and superior system reliability from composition using a large number of semiconductor devices. The line voltage is always feedback, and when an arc or a spark occurs, these are detected by the microcomputer. In addition, we design and develop algorithms using high speed and high precision microcomputer. A new conceptual control technique is adopted that RCD cuts-off by forming a forced short circuit between the phase voltage and ground in the event of an electrical accident. Some experimental tests of the proposed system also confirm practicality and the validity of the analytical results.

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Effect of Strain Rate on Microstructure Formation Behavior of M1 Magnesium Alloy During High-temperature Deformation (변형속도에 따른 M1 마그네슘 합금의 고온변형 중 미세조직 형성 거동)

  • Lee, Kyujung;Kim, Kwonhoo
    • Journal of the Korean Society for Heat Treatment
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    • v.32 no.1
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    • pp.1-11
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    • 2019
  • In this study, microstructure evolution and crystallographic orientation are investigated under various deformation conditions in M1 magnesium alloy. M1 magnesium ingot was rolled at 673 K with the rolling reduction of 30%. The compression test specimens were machined out from rolled plate, and then the specimens were annealed at 823 K for 1h. Uniaxial compression tests were conducted at 723 K and under the strain rate ranging from $5.0{\times}10^{-4}s^{-1}$ to $5.0{\times}10^{-2}s^{-1}$ up to a true strain of -1.0. For observation of crystal orientation distribution, EBSD measurement was performed. Occurrence of the dynamic recrystallization and grain boundary migration were confirmed in all case of the specimens. The distribution of the grains is not uniformed in the experimental conditions.

Trend Analysis on Korea's National R&D in Logistics

  • Jeong, Jae Yun;Cho, Gyusung;Yoon, Jieon
    • Journal of Ocean Engineering and Technology
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    • v.34 no.6
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    • pp.461-468
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    • 2020
  • This study examined how national research and development (R&D) in the domain of logistics has changed recently in the Republic of Korea. We conducted basic statistical analysis and social network analysis on 5,327 logistics-related R&D projects undertaken during 2005-2019. Data for performing these analyses were collected from the R&D database of the National Science and Technology Information Service (NTIS). By constructing a co-occurrence matrix with keywords, we conducted degree and betweenness centrality analysis and visualized the network matrix to display a cluster map. This study presents our observations related to the following findings: (1) the chronical trends of logistics R&D, (2) focused fields of logistics R&D, (3) the relations among keywords, and (4) the characteristics of logistics R&D. Finally, we suggest policy implications to boost and diversify logistics R&D.

Co-Occurrence of Two Phylogenetic Clades of Pseudoperonospora cubensis, the Causal Agent of Downy Mildew Disease, on Oriental Pickling Melon

  • Lee, Dong Jae;Lee, Jae Sung;Choi, Young-Joon
    • Mycobiology
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    • v.49 no.2
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    • pp.188-195
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    • 2021
  • The genus Pseudoperonospora, an obligate biotrophic group of Oomycota, causes the most destructive foliar downy mildew disease on many economically important crops and wild plants. A previously unreported disease by Pseudoperonospora was found on oriental pickling melon (Cucumis melo var. conomon) in Korea, which is a minor crop cultivated in the temperate climate zone of East Asia, including China, Korea, and Japan. Based on molecular phylogenetic and morphological analyses, the causal agent was identified as Pseudoperonospora cubensis, and its pathogenicity has been proven. Importantly, two phylogenetic clades of P. cubensis, harboring probably two distinct species, were detected within the same plots, suggesting simultaneous coexistence of the two clades. This is the first report of P. cubensis causing downy mildew on oriental pickling melon in Korea, and the confirmation of presence of two phylogenetic clades of this pathogen in Korea. Given the high incidence of P. cubensis and high susceptibility of oriental pickling melon to this disease, phytosanitary measures, including rapid diagnosis and effective control management, are urgently required.

Posterior reversible encephalopathy syndrome and reversible cerebral vasoconstriction syndrome associated with acute exacerbation of chronic obstructive pulmonary disease

  • Hwang, Sean;Ha, Jangwan;Choi, Min Young;Jung, Seunguk
    • Annals of Clinical Neurophysiology
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    • v.24 no.2
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    • pp.68-72
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    • 2022
  • Posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) are relatively uncommon neurological disorders. These two independent syndromes can be concurrent as a part of a continuum process; however, the specific mechanism is not well known. Although the relationship between RCVS and PRES is currently unclear, they could share a common pathophysiology. This case report aimed to determine the pathophysiology underlying the co-occurrence of PRES and RCVS in a patient with an acute exacerbation of chronic obstructive pulmonary disease.