• 제목/요약/키워드: h-Index

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영상 타원법을 이용한 인간 줄기세포의 굴절률과 두께 분포 연구 (Study on Refractive Index and Thickness of Human Stem Cells by Using Imaging Ellipsometry)

  • 최중규;심우영;이광;김상열;박상욱;제갈원;조현모;조용재
    • 한국광학회지
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    • 제20권1호
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    • pp.53-56
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    • 2009
  • 타원법을 사용하여 인간 중간엽 줄기세포의 광학상수와 두께의 영상정보를 정량적으로 구하였다. 영상 타원계를 이용하여 in vitro 환경에서 세포의 핵(nucleus)과 세포체(cell body)의 타원상수 $\Delta$, $\Psi$를 2차원 영상정보 형태로 구한 다음 각 화소별로 타원상수들을 수치해석적 역방계산하여 굴절률과 두께의 영상정보를 얻었다. 세포의 핵 영역과 세포체 영역에서 줄기세포의 두께와 굴절률 값을 2차원 영상정보 형태로 제시하였다.

연직드레인 공법에 의한 연약지반의 압밀거동 (Consolidation Behavior of Soft Ground by Prefabricated Vertical Drains)

  • 이달원;강예묵
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 1998년도 학술발표회 발표논문집
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    • pp.376-381
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    • 1998
  • The large scaled field test by prefabricated vertical drains was performed to evaluate the superiority of vertical discharge capacity for drain materials through compare and analyze the time-settlement behavior with drain spacing and the compression index and consolidation coefficient obtained by laboratory experiments and field monitoring system 1. The relation of measurement settlement( $S_{m}$) versus design settlement( $S_{t}$) and measurement consolidation ratio( $U_{m}$) versus design consolidation ratio( $U_{t}$) were shown $S_{m}$=(1.0~l.1) $S_{t}$, $U_{m}$=(1.13~l.17) $U_{t}$, at 1.0m drain spacing and $S_{m}$=(0.7~0.8) $S_{t}$, $U_{m}$=(0.92~0.99) $U_{t}$ at 1.5m drain spacing, respectively. 2. The relation of field compression index( $C_{cfield}$) and virgin compression index( $V_{cclab}$) was shown $C_{cfield}$=(1.0~1.2) $V_{cclab}$, But it was nearly same value when considered the error with determination method of virgin compression index and prediction method of total settlement. 3. field consolidation coefficient was larger than laboratory consolidation coefficient, and the consolidation coefficient ratio( $C_{h}$/ $C_{v}$) were $C_{h}$=(2.4 ~ 3.0) $C_{v}$. $C_{h}$=(3.5 ~ 4.3) $C_{v}$ at 1.0m and 1.5m drain spacing and increased with increasing of drain spacingngasing of drain spacingng spacingng

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Effects of Various Eggshell Treatments on the Egg Quality during Storage

  • Park, Y.S.;Yoo, I.J.;Jeon, K.H.;Kim, H.K.;Chang, E.J.;Oh, H.I.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권8호
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    • pp.1224-1229
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    • 2003
  • The combined effects of washing, sanitization and coating of eggshell on the physical and microbiological quality during storage were evaluated at $4^{\circ}$ and $30^{\circ}C$. The interior qualities of the eggs were assessed by weight changes, yolk index, albumen index, Haugh unit value, and microbial contamination of egg shell and egg white during 30 days of storage in untreated, washed, or sanitized and mineral oil-coated eggs. The results suggest that these changes were faster in higher temperature ($30^{\circ}C$) than lower temperature ($4^{\circ}C$) storage, and washed eggs deteriorated faster than untreated eggs. The sanitized and coated eggs maintained the best quality during storage in all parameters measured. The shelf-life of washed, sanitized and coated eggs could be extended 4-5 fold compared to that of washed or untreated eggs.

인터넷 뉴스 빅데이터를 활용한 기업 주가지수 예측 (A Prediction of Stock Price Through the Big-data Analysis)

  • 유지돈;이익선
    • 산업경영시스템학회지
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    • 제41권3호
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    • pp.154-161
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    • 2018
  • This study conducted to predict the stock market prices based on the assumption that internet news articles might have an impact and effect on the rise and fall of stock market prices. The internet news articles were tested to evaluate the accuracy by comparing predicted values of the actual stock index and the forecasting models of the companies. This paper collected stock news from the internet, and analyzed and identified the relationship with the stock price index. Since the internet news contents consist mainly of unstructured texts, this study used text mining technique and multiple regression analysis technique to analyze news articles. A company H as a representative automobile manufacturing company was selected, and prediction models for the stock price index of company H was presented. Thus two prediction models for forecasting the upturn and decline of H stock index is derived and presented. Among the two prediction models, the error value of the prediction model (1) is low, and so the prediction performance of the model (1) is relatively better than that of the prediction model (2). As the further research, if the contents of this study are supplemented by real artificial intelligent investment decision system and applied to real investment, more practical research results will be able to be developed.

SiON 박막의 광학적 특성에 대한 연구 (The study of SiON thin film for optical properlies)

  • 김도형;임기주;김기현;김현석;김상식;성만영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.247-250
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    • 2001
  • We studied optical properties of SiON thin-film in the applications of optical waveguide. SiON thin-film was grown in 300$^{\circ}C$ by PECVD(plasma enhanced chemical vapor deposition) system. The change of SiON thin-film composition and refractive Index was studied as a function of varying NH$_3$ gas flow rate. As NH$_3$ gas flow rate was increased, Quantity of N and refractive index were increased at the same time. By the results, we could form the SiON thin-film to use of a waveguide with refractive index of 1.6. We analyzed the conditions of the thin-film with FTIR(fourier transform infrared) and OES(optical emission spectroscopy). N-H bonding(3390cm$\^$-1/) can be removed by thermal annealing. And we could observe the SiH bonding state and quantity by OES analysis in SiH$_4$

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Research Output of the Pakistani Library and Information Science Authors: A Bibliometric Evaluation of Their Impact

  • Anwar, Mumtaz Ali;Jan, Sajjad Ullah
    • Journal of Information Science Theory and Practice
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    • 제5권2호
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    • pp.48-61
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    • 2017
  • This paper uses 601 cited papers of Pakistani LIS researchers with the purpose to examine the individual performance of these Library and Information Science (LIS) researchers in terms of their research output and its impact on the LIS (national/international) literature by using various bibliometric indicators. A list of 139 authors was compiled with the help of the Library, Information Science, and Technology Abstracts (LISTA) and some other sources. Data were collected from Google Scholar and SPSS version 20 was utilized in order to identify the relationship between self-citations and various performance indices of the authors. The average citations received per paper vary from 1.80 to 10.08. About half of the papers were single-authored whereas less than one-fifth were by three or more authors. The authors who worked in collaboration produced more papers and received more citations. The h-index, g-index, hI-index, hI-norm, and e-index were used to determine the rank for each author. The intra-group citations grid revealed the volume of self-citations and a small group who cite each other more due to close academic and social relationships. The correlations between self-citations and the impact indices used revealed significant differences. Findings are useful for concerned institutions regarding award, promotions, etc. Further, future research should seriously consider the self-citations and social networking of authors while examining their citations-based research performance.

테라헤르츠 분광학을 이용한 중수(D2O)와 경수(H2O) 혼합물의 특성연구 (Terahertz Characteristics of D2O and H2O Mixtures)

  • 정중건;손주혁
    • 한국광학회지
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    • 제19권6호
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    • pp.435-438
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    • 2008
  • 중수($D_2O$, 산화중수소)는 수소원자(H)보다 중성자 한 개가 더 많은 수소원자 동위원소(D)로 이루어진 물이다. 중수는 자연 상태의 물 가운데 5만분의 1정도 존재하며 경수($H_2O$)와 매우 비슷한 성질을 가지고 있으나 경수보다 11%정도 무겁고, 특이점은 235 K로 228 K인 경수와 약간의 차이를 가진다. 중수는 중성자를 흡수하여 원자로의 중성자 감속재로 쓰이고 최근 중수 농도에 따라 세포에 미치는 독성효과가 다르게 나타나는 현상이 발견 되어 암 치료에 사용하려는 연구가 진행되고 있다. 우리는 테라헤르츠 시간축 분광학을 이용하여 경수와 중수 혼합물의 농도별 굴절률과 흡수율 변화를 거대 분자간 결합에너지 영역을 포함하는 테라헤르츠 영역 ($0{\sim}2.5\;THz$)에서 측정하여 중수의 비율이 높을수록 굴절률은 감소하고 흡수율 또한 감소하는 결과를 얻었다.