• 제목/요약/키워드: relative growth

검색결과 2,241건 처리시간 0.034초

The growth and characterization of Rb-doped $KNbO_3$ nonlinear optical crystals

  • Beh, C.Y.;Chong, T.C.;Kumagai, H.;Hirano, M.
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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    • pp.149-155
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    • 1997
  • We have successfully grown colorless and transparent Rb-doped potassium niobate (KRN) single crystals using the top seeded solution growth(TSSG) technique. In our crystal growth experiments, the Rb doping concentrations within the melt range from 2-15 mol% relative to that of Nb$_2$O5. Atomic absorption measurements indicate that the Rb content in the KRN solid solution is rather low; the Rb segregation coefficient is found to be on the order of 0.05. It is believed that this is due to the relatively much larger Rb+ ionic radius compared to that of K+, rendering it more difficult for Rb to replace K in the KNbO$_3$(KN) host lattice. Preliminary single-pass second harmonic generation (SHG) experimental results indicate that there exists marginal improvement in the phase-matching temperature tolerance of KRN compared to that of pure Kn single crystals.

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곰솔에 들어있는 생장억제물질의 작용 (Effects of Growth Inhibitors form Pinus thunbergii)

  • Kil, Bong-Seop;Oh, Suk-Heum;Kim, Young-Sik
    • The Korean Journal of Ecology
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    • 제12권1호
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    • pp.21-35
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    • 1989
  • It was found that seed germination and seedling growth of selected species were inhibited by phytotoxic substance released from black pine. The longer was the aqueous extraction time of black pine needles, the smaller was the relative germination and growth of the species were inhibited in aqueous leachate and rain leachate as well as in soil underneath the black pine trees. In addition, the growth of lettuce was suppressed in volatile substances from black pine needles. To detect phytotoxic substances of black pine needles, paper chromatography and high performance liquid chromatography were used and fourteen kinds of KDICical compounds were isolated and identified as phenolic acids including benzoic acids. The growth of lettuce was inhibited in the experiment using reagents identical to these KDICical substances and a great inhibition was observed in the concentration of less than 5$\times$ M.

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고려인삼의 조직배양에 의한 사포닌 생산 (Saponin Production in Tissue Culture of Ginseng (Panax ginseng C.A. Meyer))

  • Choi, Kwang-Tae;Park, Ji-Chang;Ahn, In-Ok
    • Journal of Ginseng Research
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    • 제14권2호
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    • pp.107-111
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    • 1990
  • Ginseng root explants and calli were cultured on modified Murashine and Skoog's media supplemented with different concentrations of organic or inorganic compounds and plant growth requlators to clarify the effects of chemical compositon and plant growth regulators in the medium on the growth of ginseng calli and the production of ginseng saponin. For optimum growth of ginseng calli, the concentrations of 2, 4-D and sucrose were in the range of 1 to 5 mg/l and 1 to 3%, respectively. And it was clarified that sucrose, nitrogen, phosphate, calcium, magnesium, plant growth regulators and their concentrations influcenced the relative biosynthesis of saponin in tissue cultures of Panax ginseng.

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초음파 분무 열분해 알루미나 분체의 소결 동력학 (Sintering kinetics of ultrasonic spray pyrolyzed alumina powder)

  • 조경식
    • 한국결정성장학회지
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    • 제7권2호
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    • pp.324-333
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    • 1997
  • 초음파 분무 열분해 알루미나 분체로부터 $1600^{\circ}$~$1700^{\circ}C$ 범위의 소정 온도에서 소결한 다공질 시편의 상대밀도는 80~92%이다. 소결 온도 및 유지 시간이 길어지면 과대 입성장을 일으킨다. 소결 중의 미세 구조 발달을 이미지 분석하였다. 초음파 분무 열분해 알루미나 분체의 소성시 결정립 성장 동력학에 대한 연구로부터 정상 입성장 결정립 성장 활성화 에너지는 386.77 kJ/mol이다.

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루브라참나무의 생장과 재질 - 흡수량, 흡습성 - (Wood Quality and Growth of Quercus rubra in Korea - Water absorption, Hygroscopic property -)

  • 박강식;김병로
    • 한국가구학회지
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    • 제27권2호
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    • pp.91-95
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    • 2016
  • This study was conducted to investigate the relationship between water absorption (or hygroscopic property) and growth rate of rubra oak (Quercus rubra) from 5 different origins of seed (Carleton, Simcoe, Chatham, Bancroft, Unknown). Water absorption at cross section of Quercus rubra was $0.43{\sim}0.92g/cm^2$ and the property was not related with growth rate. Overall equilibrium moisture content of rubra oak were 11.35~11.56% and 15.15~15.83% at $40^{\circ}C$ with 75% and 90% relative humidities, respectively. There was no relationship between growth rate and moisture content(hygroscopy) in rubra oak. Based on the results, Rubra oak can be classified as a low hygroscopic wood grade, and thus might be a good raw material for furniture productions owing to its superior dimensional stability.

Relative Effectiveness of Various Development Finance Flows: A Comparative Study

  • LEE, KYE WOO;HONG, MINJI
    • KDI Journal of Economic Policy
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    • 제40권3호
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    • pp.91-115
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    • 2018
  • This paper aims to identify the most effective mode of development finance flows for the economic growth of middle-income developing and least developed countries, separately. It also attempts to confirm whether governance has any significant role in the causal relationship between development finance flows and economic growth. Policymakers in each developing country should select the most effective modality of development finance inflows among the different modalities (such as Official Development Assistance (ODA) grants, Official Development Assistance (ODA) loans, FDI, and international personal remittances) and expand it for their economic growth. Dynamic panel regression models were used on 48 least developed countries and 89 middle-income developing countries, respectively, during the Millennium Development Era: 2000-2015. The empirical analysis results show that ODA grants and remittances were most effective in promoting economic growth for least developed countries, while FDI was most effective for middle-income developing countries. These findings were not affected by the status of governance of the individual country.

Determining Canopy Growth Conditions of Paddy Rice via Ground-based Remote Sensing

  • Jo, Seunghyun;Yeom, Jongmin;Ko, Jonghan
    • 대한원격탐사학회지
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    • 제31권1호
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    • pp.11-20
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    • 2015
  • This study aimed to investigate the canopy growth conditions and the accuracy of phenological stages of paddy rice using ground-based remote sensing data. Plant growth variables including Leaf Area Index (LAI) and canopy reflectance of paddy rice were measured at the experimental fields of Chonnam National University, Gwangju, Republic of Korea during the crop seasons of 2011, 2012, and 2013. LAI values were also determined based on correlations with Vegetation Indices (VIs) obtained from the canopy reflectance. Three phenological stages (tillering, booting, and grain filling) of paddy rice could be identified using VIs and a spatial index (NIR versus red). We found that exponential relationships could be applied between LAI and the VIs of interest. This information, as well as the relationships between LAI and VIs obtained in the present study, could be used to estimate and monitor the relative growth and development of rice canopies during the growing season.

SLS(Solid-Liquid-Solid) 성장기구에 의한 탄화규소 나노튜브의 성장 (Growth of SiC Nanotube by SLS (Solid-Liquid-Solid) Growth Mechanism)

  • 노대호;김재수;변동진;양재웅;김나리
    • 한국재료학회지
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    • 제14권2호
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    • pp.83-89
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    • 2004
  • SiC nanotubes were synthesized by SLS growth mechanism using various metal catalysts. Synthesized nanotubes had mean diameters of 20~50 nm and several $\mu\textrm{m}$ length. The kind of catalysts affected microstructures of SiC nanotubes by different diffusion routes. These differences are attributed to catalysts' physical properties and relative activities to the graphite substrate. Fe acted as a good catalyst of SLS growth mechanism. But in case of Ni, SiC nanotubes grew slowly. Optical property was measured by photoluminescence measurement. Relatively broad peak was obtained and mean peak positioned at about 430 nm. This result was the same as other nanocrystalline SiC materials, but was different from the results of bulk SiC probably due to quantum confinement effect and defect in the grown SiC nanotube.

A Trend Analysis of Competition Positioning in Korean Seaport by Using BCG Matrix

  • Park, Ro-Kyung
    • 한국항만경제학회:학술대회논문집
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    • 한국항만경제학회 2006년도 국제학술대회
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    • pp.253-276
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    • 2006
  • This paper has shown the trend of competition positioning of 26 Korean ports in 1994, 1999, and 2003 by using BCG matrix which consists of relative market shares, growth rate of cargo handling, and also growth rate and CCR and BCC efficiency scores with scale efficiency scores in the vertical and horizontal axes. The empirical main results are as follows. First, Incheon Port, Pyungtag Port, Gwangyang Port, Busan Port, Pohang Port and Woolsan Port have shown their competitive positioning in terms of market share and growth rate. Second, Pyungtag Port, Wando Port, Tongyoung Port, Gohyun Port, Samcheog Port, and Okgae Port have their competitive positioning in terms of growth rate and scale efficiency scores. The main policy implication of this paper is to emphasize that BCG matrix method using in this paper can give seaport manager the basic information for planning the future port management for enhancing the competitive positioning among Korean seaports.

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PRODUCTION OF GINSENOSIDES THROUGH IN VITRO CULTURE OF GINSENG(Panax ginseng C.A. MEYER)

  • Choi K.T.;Ahn I.O.;Park J.C.
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1993년도 학술대회지
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    • pp.143-149
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    • 1993
  • Ginseng root explants and calli induced from selected cell lines were cultured on modified Murashige and Skoog's media supplemented with different concentrations of organic or inorganic compounds and plant growth requlators to clarify the effects of chemical composition and plant growth regulators in the medium on the growth of ginseng calli and the production of ginseng saponin. For optimum growth of calli, the concentrations of 2, 4-D and sucrose were the range of 1 to 3 mg/${\ell}$l and 1 to $3\%,$ respectively. And it was clarified that sucrose, nitrogen, phosphate, calcium, magmesian plant growth regulators and their concentrations influcenced the relative biosynthesis of saponin in tissue cultures of Panax ginseng. The patterns of ginsenosides, pharmacologically useful component, were different among the cell lines and contents of ginsenosides were much higher in selected cell lines than in original cell line.

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