• 제목/요약/키워드: Growth time

검색결과 9,456건 처리시간 0.045초

Lateral growth of PEO films on Al7050 alloy in 0.1 M NaAlO2

  • Moon, Sungmo;Kim, Gi Yeob
    • 한국표면공학회지
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    • 제54권4호
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    • pp.200-208
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    • 2021
  • This paper investigated generation behavior of micro-arcs and growth behavior of PEO films on the AA7050 disc specimen in 0.1 M NaAlO2 solution under the application of 1200 Hz anodic pulse current. Morphologies, thickness and surface roughness of PEO films were examined at the edge part and central part separately. Micro-arcs were generated first at the edge part and then moved towards the central part with PEO treatment time, indicating lateral growth of PEO films. The lateral growth resulted in uniform PEO thickness of about 5 ㎛ and surface roughness of about 0.5 ㎛. Moving of the arcs from the edge towards the central part appeared only one time and large size arcs were generated at the edge before completing the central part with small size micro-arcs. This suggests that vertical growth starts before completing the lateral growth. Large size arcs generated at the edge resulted in the formation of relatively large size pores within the PEO films on the AA7050 disc specimen.

A Study on the Interrelationship of Trade, Investment and Economic Growth in Myanmar: Policy Implications from South Korea's Economic Growth

  • Oo, Thunt Htut;Lee, Keon-Hyeong
    • Journal of Korea Trade
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    • 제24권1호
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    • pp.146-170
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    • 2020
  • Purpose - This paper addresses the concepts of FDI-Trade-Growth nexus in Myanmar's economy and empirically investigates the interrelationships of trade, investment and economic growth to reveal the growth model of Myanmar's economy. Additionally, this paper also addresses the cooperative strategies between Myanmar and South Korea through a case study related to South Korea's economic growth. Design/methodology - Our empirical model considers the interrelationship among FDI, trade, growth, labor force and inflation in Myanmar. This study employs ARDL (Autoregressive Distributed Lag) to conduct an analysis of the FDI-Trade-Growth relationships using the time series data from 1970 to 2016 and a conducted case study of South Korea provided for practical implication on cooperative strategies between Myanmar and Korea. Findings - Export equation was chosen through the diagnostic tests. Our main findings can be summarized as follows: Export in Myanmar is positively influenced by labor force, FDI, capital formation and negatively impacted by import and instable inflation rate in the long run. In the short run, GDP and import positively influence export. The Granger causality test proves that Myanmar is an FDI/labor force-led Growth economy, where FDI and labor force are main drivers of export followed by GDP in Myanmar. The case study of South Korea provided that Korea's tax and credit system for promoting export-led FDI industries and cooperative units for joint ventures between Korea and Myanmar in export-led FDI industries are recommended. Originality/value - No study has yet to be conducted on the interrelationships of macroeconomic factors from the perspectives of FDI-Trade-Growth Nexus in Myanmar under the assumption of labor force and inflation rate as fundamental conditions. The current study also covered a relatively longer period of time series data from 1970 to 2016. This paper also conducts a case study of South Korea's experience in order to evaluate the findings and provide better policy implications.

강화 남부 조간대에 서식하는 칠면초(Suaeda japonica)의 연간 생장 및 생산 양상 (Growth Rate and Annual Production of Halo-phyte (Suaeda japonica) on Tidal Mud-flat, Southern Part of Ganghwa-Isl, Korea)

  • 황지원;이균우;박흥식
    • Ocean and Polar Research
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    • 제44권2호
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    • pp.127-137
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    • 2022
  • This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m2/yr, and the highest production was 519 gDWt/m2/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m2/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

Modeling the Growth of Neurology Literature

  • Hadagali, Gururaj S.;Anandhalli, Gavisiddappa
    • Journal of Information Science Theory and Practice
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    • 제3권3호
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    • pp.45-63
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    • 2015
  • The word ‘growth’ represents an increase in actual size, implying a change of state. In science and technology, growth may imply an increase in number of institutions, scientists, or publications, etc. The present study demonstrates the growth of neurology literature for the period 1961-2010. A total of 291,702 records were extracted from the Science Direct Database for fifty years. The Relative Growth Rate (RGR) and Doubling Time (Dt.) of neurology literature have been calculated, supplementing with different growth patterns to check whether neurology literature fits exponential, linear, or logistic models. The results of the study indicate that the growth of literature in neurology does not follow the linear, or logistic growth model. However, it follows closely the exponential growth model. The study concludes that there has been a consistent trend towards increased growth of literature in the field of neurology.

The Changing Roles of Ownership in the Economic Growth in China

  • Lee, Hyuntai
    • 분석과 대안
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    • 제4권2호
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    • pp.39-70
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    • 2020
  • This paper examines the changing roles of ownership in the economic growth by using a panel data set of 30 provinces in China for the period (1999-2010). With the use of absolute and relative presence variables, this study shows that private enterprises have emerged as the engine of economic growth in China in the later period (2005-2010). The growing size and number of private enterprises are positively linked to growth. However, though foreign-invested enterprises have been acclaimed as the main contributors to economic growth in China, they have minimal effect on the economic growth in the later period. State-owned enterprises have a significant and negative effect on the economic growth in the later period. The results can be interpreted that the engine of growth in China has been changed over time from other ownerships to private ownership. Private companies have developed a lot in every respect and started to lead the economy for long-run growth. China initiated its economic growth by adopting foreign capital and it is still the top destination for foreign direct investment among developing countries. However, to sustain the growth over a long period, private sector should be of great importance and perform a key role in the view of catch-up economics.

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Sodium polyanethol sulfonate의 혈액배양에서의 Salmonella typhi 분리에 대한 영향 (Effect of sodium polyanethol sulfonate on the isolation of Salmonella typhi from blood culture)

  • 정윤섭
    • 대한미생물학회지
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    • 제9권1호
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    • pp.13-18
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    • 1974
  • Blood is one of the most important clinical specimens for the isolation of bacteria. A rapid isolation and a high isolation rate of bacteria are very important in blood culture because bacteremic patients are mostly in grave condition. Various blood culture media which support growth of most fastidious bacteria are available commercially. However, growth of bacteria are frequently delayed because of antibacterial activity of blood. Sodium polyanethol sulfonate(Liquoid) has been reported to inactivate the antibacterial substance and disrupt phagocytic cells. The beneficial effect of SPS is well recognized in the isolation of gram-positive bacteria. However, the effect does not seem to be prominent for gram-negative bacilli isolation mainly due to the rapidity of their growth. It has been experienced with Sal. typhi that the growth is much slower than that of other gram-negative bacilli. For the rapid growth of the organism, use of bile broth has been recommended. Although Sal. typhi is the most frequently isolated organism at present, about one half of total isolates are other organisms and, in case bile broth is used, other media which support growth of these organisms should be used together. Fluid thioglycollate medium(FTM) which is always used in blood culture to isolate anaerobes is inferior to brain heart infusion(BHI) for the isolation of aerobes. This study was done to determine the effect of SPS on the isolation of Sal. typhi from blood. During the Sep. 1973 to Sep. 1974 study period, 2460 blood cultures were made from the Severance hospital patients: BHI and FTM sets 1431 specimens, BHI with SPS(0.05%) and FTM sets 396 specimens, BHI and FTM with SPS sets 359 specimens, BHI and BHI with SPS sets 274 specimens. Mean incubation time required for the macroscopic detection of growth of Sal. typhi were 3.5 days on BHI and 2.7 days on BHI with SPS. The 0.8 day difference was statistically significant. On FTM the mean incubation time was 3.8 days while it was 2.9 days on FTM with SPS. The 0.9 day difference was statistically significant. The result on BHI with and without SPS sets showed faster growth on BRI with SPS in 7 specimens and slower growth in one specimen and the remaining 12 showed growth at the same time. These specimens had mean incubation time of 3.2 days on BHI and 2.3 days on BHI with SPS. The 0.9 day difference was statistically significant. This study indicates beneficial effect of SPS for the rapid isolation of Sal. typhi from clinical blood specimens.

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HVPE를 이용하여 r-plane 사파이어 위에 multi-step으로 성장시킨 a-plane GaN 에피층의 특성 연구 (Multi-step growth of a-plane GaN epitaxial layer on r-plane sapphire substrate by HVPE method)

  • 이원준;박미선;장연숙;이원재;하주형;최영준;이혜용;김홍승
    • 한국결정성장학회지
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    • 제26권3호
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    • pp.89-94
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    • 2016
  • 본 연구에서는 HVPE(Hydride Vapor Phase Epitaxy)를 이용하여 각각 다른 V/III ratio를 가지는 multi-step의 성장 시간 변화에 따라 r-plane 사파이어 위에 성장되는 a-plane GaN 에피층의 결정성에 대하여 연구하였다. 또한 이번 연구의 결과를 선행 연구에서 single-step으로 r-plane 사파이어 위에 성장시킨 a-GaN 에피층의 결과와 비교하였다. Multi-step으로 r-plane 사파이어 위에 a-plane GaN 에피층을 성장시켰을 때, source HCl의 유량과 성장 시간이 증가함에 따라 a-plane GaN 에피층에 대한 rocking curve의 FWHM(Full Width at Half Maximum) 값이 감소하였다. 높은 source HCl의 유량을 갖는 first step과 second step의 성장 시간과 source HCl의 유량이 증가할수록 a-plane GaN 에피층 내부의 void가 감소하였다. 결과적으로 first step과 second step의 성장 시간이 가장 긴 조건에서 성장된 a-plane GaN 에피층이 가장 낮은 FWHM 값인 584 arcsec을 가지며, azimuth angle의 의존도가 가장 적은 것으로 확인되었다.

볏짚배지의 살균조건이 느타리버섯균의 균사생장에 미치는 영향 (Effect of Pasteurized Substrates in Various Condition on the Mycelial Growth of Oyster Mushroom, Pleurotus spp.)

  • 전창성;신동훈;박정식;오세종
    • 한국균학회지
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    • 제28권2호
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    • pp.103-108
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    • 2000
  • 느타리버섯 재배용 볏짚배지의 살균과 관련하여 균사생장에 미치는 영향을 실내에서 시험한 결과, 느타리버섯의 균사생장은 $60^{\circ}C$에서 살균한 것이 가장 우수하였고 살균온도가 높아질수록 감소되었으며, 병원균의 생장은 $121^{\circ}C$에서 가장 양호하고 온도가 낮을수록 감소되었다. 볏짚배지의 살균시간은 8, 12시간에서 느타리버섯의 균사생장이 가장 양호하였고 24시간 처리에서는 오히려 균사생장이 감소되었다. 살균시간과 침수시간에 따른 배지 pH의 변화는 침수시간이 길어지면 산도가 낮아지고 살균과 후발효후 종균접종시에는 전반적으로 균형을 이루었다. 느타리버섯 볏짚배지의 살균시간에 상관없이 균사생장정도는 $25{\sim}30^{\circ}C$에서 가장 양호하였다. 느타리버섯의 볏짚배지는 2회 살균보다는 1회 살균시 균사생장이 양호하였다. 미리 균상 내에서 전발효를 하는 경우는 오히려 정상적인 것보다는 균사생장이 불량하였다.

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Error Structure of Technological Growth Models A Study of Selection Techniques for Technological Forecasting Models

  • Oh, Hyun-Seung;Yim, Dong-Soon;Moon, Gee-Ju
    • 품질경영학회지
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    • 제23권1호
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    • pp.95-105
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    • 1995
  • The error structure of nonlinearized technological growth models, such as, the Pearl curve, the Gompertz curve and the Wei bull growth curve, has zero mean and a constant variance over time. Transformed models, however, like the linearized Fisher-Pry model. the linearized Gompertz growth curve, and the linearized Weibull growth curve have increasing variance from t = 0 to the inflection point.

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반응 용기법을 이용한 InP/ZnS 양자점 합성과정에서 InP 코어의 성장기구 (Growth mechanism of InP and InP/ZnS synthesis using colloidal synthesis)

  • 서한욱;정다운;이빈;현승균;김범성
    • 한국분말재료학회지
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    • 제24권1호
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    • pp.6-10
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    • 2017
  • This study investigates the main growth mechanism of InP during InP/ZnS reaction of quantum dots (QDs). The size of the InP core, considering a synthesis time of 1-30 min, increased from the initial 2.56 nm to 3.97 nm. As a result of applying the proposed particle growth model, the migration mechanism, with time index 7, was found to be the main reaction. In addition, after the removal of unreacted In and P precursors from bath, further InP growth (of up to 4.19 nm (5%)), was observed when ZnS was added. The full width at half maximum (FWHM) of the synthesized InP/ZnS quantum dots was found to be relatively uniform, measuring about 59 nm. However, kinetic growth mechanism provides limited information for InP / ZnS core shell QDs, because the surface state of InP changes with reaction time. Further study is necessary, in order to clearly determine the kinetic growth mechanism of InP / ZnS core shell QDs.