• Title/Summary/Keyword: Time-lag effect

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한국의 연구개발투자와 경제성장간의 관계분석

  • 최은철
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 2000.11a
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    • pp.346-356
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    • 2000
  • This paper aims to analyse the relationship between R&D investment and economic growth in Korea. The analysis result shows 38 percent of average economic growth rate(7.1%) of Korea between 1976 and 1998 was achieved by the growth of Total Factor Productivity (TFP), and the R&D investment during the period contributed in achieving the economic growth rate by as much as 9.86 percent. In the process of the estimate, the rate of return of the R&D investment from both government and private was calculated as 47 percent. The relationship between private R&D investment, government R&D investment and the GDP was also investigated, and it was estimated that the private sector invested 2.0 percent of the GDP in R&D during the period, and was found that 1 won of government R&D investment induced 0.202 won of private sector's R&D investment. However, the time-lag effect, which is naturally believed to exist between the R&D investment and the economic growth, could not be analysed in a mathematical form, because of the lack of the data to establish this relationship. However, this paper believe that the time-lag effect in this relationship was included implicitly by using the data of 23 years.

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Experimental Study to Evaluate the Thermal and Condensation Performance of Steel Stud Walls in Steel-Framed Schools (철골조학교(鐵骨造學校) 스틸스터드 벽체(壁體)의 단열(斷熱) 및 결로방지(結露防止) 성능(性能) 평가(評價)를 위한 실험적(實驗的) 연구(硏究))

  • Yu, Young-Dong;Kim, Gap-Dug
    • Journal of the Korean Institute of Educational Facilities
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    • v.6 no.4
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    • pp.16-23
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    • 1999
  • The thermal and condensation performance of steel stud walls are monitored in steel-framed schools of Ee-Wol Elementary School and kindergarten using temperature and humidity sensors installed. The monitoring process carried out during the summer and winter period, shows decrement effect of the external heat flow to be quite remarkable and excellent. And steel stud walls provides a highly efficient time-lag effect in spite of its light weight property, with 30 minutes to 4 hours time-lag for external heat flow, which variation mainly depends on its location of each part of the wall. Any condensation phenomena are not observed in either external or internal surfaces.

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Effect of Dual Substrates on Aniline Mineralization by Pseudomonas testosteroni 6F1 (Pseudomonas testosteroni 6F1의 아닐린 분해에 미치는 이차기질의 영향)

  • Cho, Kyung-Yun;Chun, Hyo-Kon;Bae, Kyung-Sook;Kho, Young-Hee
    • Microbiology and Biotechnology Letters
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    • v.16 no.5
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    • pp.427-431
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    • 1988
  • The simultaneons mineralization of aniline and other secondary carbon sources by Pseudomonas testosteroni 6Fl were evaluated by the lag time and the enzyme induction level. The lag time for aniline mineralization by P. testosteroni 6Fl was 7 hours, whereas the lag time for aniline and readily utilizable secondary substrates were 1-3 hours. This stimulated degradation resulted from the simultaneous use of secondary substrates and aniline, the increased rate of enzyme induction, and the in-creased rate of the cell growth. The enzyme induction level of P. testosteron 6F1 were varied according to the kinds of secondary substrate.

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Hydrogeologic Parameter Estimation by Using Tidal Method in a Fractured Rock Aquifer (단열암반 대수층에서 조석분석법을 이용한 수리상수 추정)

  • Shim Byoung Ohan;Chung Sang Yong
    • Journal of Soil and Groundwater Environment
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    • v.9 no.3
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    • pp.27-32
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    • 2004
  • The oceanic tides have an effect on groundwater levels in coastal fractured rock aquifers. The observed groundwater table fluctuations caused by the effective stress through an aquifer are shown as sine curves similar with tidal fluctuation. To estimate a hydrogeologic parameter, tidal method is utilized with groundwater level fluctuations of two monitoring wells. Cross correlation function is used to calculate time lags between observed groundwater levels and tide, and the deeper well shows longer time lag. The storage coefficients calculated by using tidal efficiency and time lag show large differences. The storage coefficients obtained by using time lags are close to the result of slug test, and that of the deeper well shows closer value by slug test. The tidal efficiency is unsatisfied to apply in the tidal method because of an effect of phreatic aquifer and the vertical flow of groundwater through fractured confining bed. This tidal method can be an economical and effective way to define the parameter by considering the location of observation well and hydrogeologic characteristics of a coastal aquifer.

A Study on the Changing Trajectory of Game Use and the Current and Lag Effect from Self-Control during Early Adolescences (초기 청소년의 게임사용 변화궤적과 자기통제력의 동시효과 및 지연효과 연구)

  • Heo, Gyun
    • The Journal of Korean Association of Computer Education
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    • v.15 no.3
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    • pp.71-80
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    • 2012
  • The purpose of this study is to find out the changing trajectory of online game use as the development of early adolescences. It is also to explore whether the self-control has a current and a lag effect on the game use while development of students. We found these results: (a) There is a statically significant individual variability in initial levels and rates of change in online game use over time. The change of trajectory is declined. (b) Boys also have higher rate of the change in using game than girls over time. (c) Both initial state and changing rate of online game use affects negatively the academic achievement. (d) Current effect always supports, but lag effect does not support except the period from last elementary school grade to middle school grade as explanations for the developmental relation between self-control and online game use in young adolescents.

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Analysis Method of the Effect of National R&D investments on Economic Growth

  • Choi, Eun-Chul
    • Journal of Technology Innovation
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    • v.7 no.2
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    • pp.1-20
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    • 1999
  • This paper investigates the effects of various R&D investments on economic growth empirically. To this end, the relationships between various R&D investments and economic growth are analysed, and the rates of return of R&D investments are estimated. Furthermore, the effect of government R&D investment on private sector R&D investment, and the effect of social factors, which affect the relationship between the R&D inputs and economic growth, are analysed. Based on the results of this analysis, a simulation model is developed, which shows the relationship between R&D investments and economic growth rate; this model is verified by analysing the correlation between the actual and the estimated economic growth rate, using the data between 1981 and 1995 of eight selected countries. The validation results show that the simulation model has sufficient accuracy to be used for evaluating and proposing R&D policies for the countries for which appropriate data is available. However, the time-lag effect, which is naturally believed to exist between the R&D input and the economic growth, could not be analysed in a mathematical form, because of the lack of the data to establish this relationship. Thus, when estimating the relationship between them, the time-lag effect in this relationship was included implicitly by using the data of fifteen years.

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A Time Lag Analysis of R & D Effect ell Total Factor Productivity in Information and Communication Industry (시차분석을 통한 정보통신산업 연군개발투자가 총요소생산성에 미치는 효과 연구)

  • Lee, Kyung-Suk;Park, Myeong-Cheol;Lee, Duk-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.2B
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    • pp.154-163
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    • 2006
  • The importance of R & D investment has dramatically been increased as industrial paradigm rapidly changes to knowledge-based economy. In order to preserve recent economic growth and reinforce competitive advantage, government policy and regulatory framework needs to be reshaped in ways that minimize the distorted use of limited resources and maximize the efficiency of R & D investment. In this regards, this paper aims to investigate the influence of R & D investment in national economic growth and to compare the effectiveness of IT R & D investment with other industries, in respect to the time lag.

Short-term Effect of Ambient Air Pollution on Emergency Department Visits for Diabetic Coma in Seoul, Korea

  • Kim, Hyunmee;Kim, Woojin;Choi, Jee Eun;Kim, Changsoo;Sohn, Jungwoo
    • Journal of Preventive Medicine and Public Health
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    • v.51 no.6
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    • pp.265-274
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    • 2018
  • Objectives: A positive association between air pollution and both the incidence and prevalence of diabetes mellitus (DM) has been reported in some epidemiologic and animal studies, but little research has evaluated the relationship between air pollution and diabetic coma. Diabetic coma is an acute complication of DM caused by diabetic ketoacidosis or hyperosmolar hyperglycemic state, which is characterized by extreme hyperglycemia accompanied by coma. We conducted a time-series study with a generalized additive model using a distributed-lag non-linear model to assess the association between ambient air pollution (particulate matter less than $10{\mu}m$ in aerodynamic diameter, nitrogen dioxide [$NO_2$], sulfur dioxide, carbon monoxide, and ozone) and emergency department (ED) visits for DM with coma in Seoul, Korea from 2005 to 2009. Methods: The ED data and medical records from the 3 years previous to each diabetic coma event were obtained from the Health Insurance Review and Assessment Service to examine the relationship with air pollutants. Results: Overall, the adjusted relative risks (RRs) for an interquartile range (IQR) increment of $NO_2$ was statistically significant at lag 1 (RR, 1.125; 95% confidence interval [CI], 1.039 to 1.219) in a single-lag model and both lag 0-1 (RR, 1.120; 95% CI, 1.028 to 1.219) and lag 0-3 (RR, 1.092; 95% CI, 1.005 to 1.186) in a cumulative-lag model. In a subgroup analysis, significant positive RRs were found for females for per-IQR increments of $NO_2$ at cumulative lag 0-3 (RR, 1.149; 95% CI, 1.022 to 1.291). Conclusions: The results of our study suggest that ambient air pollution, specifically $NO_2$, is associated with ED visits for diabetic coma.

Analysis of the effect of imported technology on the economic growth of Korea (한국의 경제성장에 있어서 해외도입기술의 영향분석)

  • 최은철
    • Proceedings of the Technology Innovation Conference
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    • 2001.06a
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    • pp.145-156
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    • 2001
  • This paper investigates the effect of imported technology on the economic growth of Korea. To this end, the relationship between input technology and economic growth are suggested in the numerical form and analysed empirically. The rates of return of technology investments, which are divided into the domestic R&D investment and the investment on imported technology, are estimated. Based on the result of this analysis, the rate of return of the input technology, which includes the domestic R&D investment and the investment on imported technology, are estimated as 31.4%, and this input technology is calculated as to contribute 8.9% on the economic growth rate of Korea. And the domestic R&D investment is fumed out to have bigger rate of return than the investment on imported technology during the surveyed period. However, the rates of return of detailed R&D investments, which can be divided into the investments on commercial R&D and basic science, were not calculated in this paper, because of the lack of data on this in this paper. As well, the time-lag effect, which is naturally believed to exist between the R&D investment and the economic growth, could not be analysed wit:1 the same reason. Thus when analysing the relationship between them, this paper tried to minimize the time-lag effect by using the long-term data of twenty-three years.

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An Empirical Analysis on the Spillover Effects of R&D Investment in the ICT industry (ICT 산업의 R&D 투자가 타 산업에 미치는 파급효과 측정)

  • Jung, Woo-Jin;Kim, Hyunsuk;Cho, Shin
    • Knowledge Management Research
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    • v.20 no.1
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    • pp.27-43
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    • 2019
  • This paper examines spillover effects of R&D investment in the ICT industry to other industries by analyzing panel data composed of 6 manufacturing industries for the period of 1983~2011. Major findings are as follows; (1) The increase of R&D investment in ICT industry has a significantly positive relationship with the increase in the value-added of the remaining 5 industries with 3~10 year lags, depending on the source of R&D funds and R&D stage. (2) More specifically, public R&D shows the spillover effects during 3~7-year lag periods, whereas private R&D started to exert spillover effects from 9-year lag. The result implies that the public R&D appropriately targets projects with more spillover effects. (3) Basic research, applied research, and development showed the spillover effects for the period of 9~10, 7~10, and 10-year lag, respectively. (4) The R&D investment in 5 other industries such as machinery, chemicals, and materials does not have positive spillover effects to the remaining industries. Few studies have been done to analyze the R&D spillover effects to other industries, with certain limitations. This study contributes to the existing literature by analyzing the spillover effects of the different R&D funds and R&D stages, and by considering various time-lag effects.