• Proceedings of the Korea Association of Crystal Growth Conference
• /
• 1999.06a
• /
• pp.271-284
• /
• 1999

As a semiconductor material for electronic devices operated under extreme environmental conditions, silicon carbides (SiCs) have been intensively studied because of their excellent electrical, thermal and other physical properties. The growth characteristics of single-crystalline 4H-SiC homoepitaxial layers grown by a thermal chemical vapor deposition (CVD) were investigated. Especially, the successful growth condition of 4H-SiC homoepitaxial layers using a SiC-uncoated graphite susceptor that utilized Mo-plates was obtained. The CVD growth was performed in an RF-induction heated atmospheric pressure chamber and carried out using off-oriented substrates prepared by a modified Lely method. In order to investigate the crystallinity of grown epilayers, Nomarski optical microscopy, Raman spectroscopy, photoluminescence(PL), scanning electron microscopy (SEM) and other techniques were utilized. The best quality of 4H-SiC homoepitaxial layers was observed in conditions of growth temperature 1500$^{\circ}C$ and C/Si flow ratio 2.0 of C3H3 0.2sccm & SiH4 0.3sccm. The growth rate of epilayers was about 1.0$\mu\textrm{m}$/h in the above growth condition.

• The Journal of Asian Finance, Economics and Business
• /
• v.8 no.4
• /
• pp.33-42
• /
• 2021

This study aims to investigate the relationship between foreign direct investment (FDI) and economic growth at the provincial level by using time-series data in Binh Dinh from 1997 to 2019. We applied the quantitative approaches Vector Autoregression (VAR) and Autoregressive Distributed Lags (ARDL) in the model, which includes economic growth, real foreign direct investment capital, ratio of trained workers, and infrastructure. The results show that all these variables are stationary at the first difference. In ARDL analysis, we found that the economic growth positively affects FDI attraction. However, there is no evidence of the effect of FDI on economic growth in the condition of low capital implemented. Moreover, findings also show that the impact of FDI on economic growth is influenced by two factors: infrastructure and human capital. The lack of human capital, which is trained personnel and infrastructure, is the main barrier hindering and inhibiting FDI's contribution to local economic growth. In order to improve the efficiency of FDI on economic growth in the future, it is suggested that the Binh Dinh government should have proper policies in terms of the infrastructure, the human capital investment. They would allow Binh Dinh to enhance the capital absorptive capacity and capital efficiency.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.4
• /
• pp.475-481
• /
• 1996

This study was carried out to acquire the basic information of root growth under different pot size, imposing different space limitation on rhizosphere. Different size of pots that had same surface area but different depth, 5cm(Iength)$\times$5cm(width)$\times$30, 15, 5cm(depth), were used during the seedling stage of tobacco plant. Space limitation on rhizosphere affected not only the aerial growth, stem height, leaf area and shoot dry weight, but also root growth and root architecture. Aerial growth was highly related to growth of underground part, so space limitation on rhizosphere decreased aerial growth. Limitation on pot volume by reducing pot depth induced new rooting on crown. Root number and relative multiplication rate were higher in small pot that had 5cm depth than large pot, but total root length and mean extension rate showed reverse patterns. Root numbers of 1st order and 2nd order were increased as pot depth was increased, but the root number of 3rd order was increased in small pot. Root system of seedling grown in large pot distributed more horizontally than that in small pot at 20 days after temporary planting (DAT), but the root architecture of seedling was reversed at 25 DAT.

• The Journal of Asian Finance, Economics and Business
• /
• v.3 no.3
• /
• pp.27-37
• /
• 2016

This study uses an endogenous economic growth model to determine the long run relationship between trade openness and economic growth in China by using the data 1975-2009.It contributes to the literature by developing trade openness index. An autoregressive distributed lag approach to cointegration and rolling regression method are employed. This study tests the link between trade openness and economic growth in the case of China by using the framework of endogenous economic growth model. This study also employs the rolling window regression method in order to examine the stability of coefficients throughout the sample span. The autoregressive distributed lag (ARDL) cointegration technique and rolling regression method are used. The empirical findings indicate that trade openness (i.e. Both individual trade indicator and composite trade openness index) are positively related to economic growth in the long run and short run. Our results indicate that trade openness as measured by individual trade indicator and composite trade openness index are positively related to economic growth in the long run and short run. However, results from the rolling window suggest that trade openness is negatively linked to economic growth only for a number of years.

• The Korean Journal of Ecology
• /
• v.18 no.1
• /
• pp.189-201
• /
• 1995

In order to clarify regeneration processes and mechanisms of the disturbed Pinus densiflora forest, responses of Pinus densiflora to gap formed by disturbance were analysed by growth of saplings and mature and growth equations were obtained from branch growth of mature trees and height growth of saplings, and age distribution of saplings and young trees recruited within gap was analysed in relation to gap age. Height growth of saplings within gaps was accelerated after gap formation. Such abrupt increases of growth of saplings after the gap formation might be resulted in the difference of growth of saplings between gap and non-gap areas. In fact, height and diameter of saplings in the central part of gap were larger than those of saplings in marginal parts of gap and non-gap area. However, density of saplings was not different in both parts. In addition, growth of annual rings of mature trees bordering on gap also increased after gap formation. Branch growth of mature trees bodering on gap was 6.3 - 6.5 cm /year and the mean radius of gaps created by death of only one canopy tree was about 3 m. Therefore, for those gaps to be closed by branch growth it will take 46 years. Growth of saplings within gap showed exponential equation. Fifty years will be required for the saplings to enter the forest canopy by the exponential growth equation. Therefore, gap created by only one tree might be closed by branch growth of surrounding canopy trees in advance of being done by height growth of saplings. But gaps created by death of trees more than 2 will be closed by the growth of saplings. Among the regenerating saplings and young trees within gaps, individuals established in advance of gap formation were more than those established after the gap formation. From these results, it was assumed that the disturbed Pinus densiflora forests in these sites were regenerated by height growth of saplings recruited in advance of gap formation.

• Journal of the Korean association of regional geographers
• /
• v.17 no.1
• /
• pp.96-108
• /
• 2011

In spite of arduous policy efforts to address the deprived region problem emerged in the rapid industrialization and urbanization processes since the 1960s, it is well acknowledged that there are some policy limitations. In a recent effort to improve the policy for the deprived regions, the national territory is divided into 4 groups such as urban, rural, growth promotion, and special situation areas and various policies for the deprived regions have been consolidated into a policy for the growth promotion areas. The purpose of the study is to classify the already-designated 70 growth promotion areas and examine the differentiated characteristics of different types in order to propose more regionally situated policy approach to the deprived areas. The study shows that the types of the 70 growth promotion areas are much differentiated one another in terms of internal characteristics and dynamics. It is therefore further argued that the policy efforts need to be area-specific in order to address the policy demand for the deprives regions in a more efficient way.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.14 no.1
• /
• pp.12-16
• /
• 2004

In this study, we have investigated the development of the crystal growth stability and reproducibility for large and high-quality DAST. DAST crystal were grown from a saturated methanol solution by a slow cooling method and DAST was synthesized by the condensation of 4-methyl-n-methyl pyridinum tosylate, which was prepared from 4-pocoline and methyl toluenesulponate and 4-N-dimethyl amino-bezaldehyde in the presence of piperidine. We had synthesized DAST crystals in dry Argon atmosphere in order to avoid the formation of hydride organge co-crystals, DAST$.$$H_2O$. Since DAST molecules crystallize in a humid atmosphere, crystal structure become centrosymmetric, and then second order NLO (nonlinear optical) properties would be disappeared. We fixed the growth orientation of DAST crystal (001) surface. The crystal growth was proceeded at a cooling rate of $H_2O$/day and the cooling period is for 4 days. The dimensions of seed crystal was $2.5\times 3.6\times0.4\textrm{mm}^3$ and we have obtained a DAST crystal with the dimension of $10\times 10.5\times3.0\textrm{mm}^3$. The color of grown DAST crystal is red and it's surface appears to be metallic green.

• Journal of Plant Biology
• /
• v.24 no.1
• /
• pp.13-19
• /
• 1981

In order to investigate the effects of ammonium citrate and ammonium succinate on the growth and absorption of nitrogen compounds supplied in the medium, Korean ginseng (Panax ginseng C. A. Meyer) calli were suspension cultured in MS medium with various concentrations of ammonium citrate and ammonium succinate. When Korean ginseng calli were cultured with 10 mM ammonium citrate, 10 mM ammonium succinate, and 10 mM ammonium nitrate (control) in MS media as the nitrogen sources, the growth, $NO_3$-N absorption and total nitrogen content of the Korean ginseng cells were greatest in the ammonium citrate and ammonium succinate concentrations. When Korean ginseng calli were cultured with 5 mM ammonium citrate and 5 mM ammonium succinate, the growth and nitrogen content were superior to those of the control: however, $NO_3$-N and $NH_4$-N absorptions were similar to those of the control. In conclusion, the 10 mM ammonium citrate and 10 mM ammonium succinate may be better able to facilitate the growth and $NO_3$

• Journal of Korean Society of Forest Science
• /
• v.104 no.4
• /
• pp.677-684
• /
• 2015

This study analyzed a long-run growth trend of the forestry sector in the Republic of Korea, and forecasted the potential growth in the future after investigating main drivers of growth in the forestry sector through growth accounting analysis. Based on results, we finally suggested a direction to go forward in order to achieve a sustainable growth in the field. After Asia financial crisis, the growth rate of the forestry sector was getting stable with the fast recovery of Korean economy. While the main drivers of growth in the field was labor and capital accumulation in 1980s and 1990s, the main driver of growth has been the increment of capital accumulation since 2000. As the result of our analysis for forecasting the potential growth in the field, the contribution of labor, capital, TFP in total growth is expected as 0.09%, 1.58%, and -0.01%, respectively. The potential growth rate of the forestry sector during 2012-2020 is predicted to be 1.65% and the total production will become 36.25 trillion won.

• Journal of Plant Biology
• /
• v.32 no.3
• /
• pp.137-144
• /
• 1989

In order to clarify the effect of the associative nitrogen fixing bacteria on the growth of corn(Zea mays L. Suwon19), we inoculated corn seedlings with Azospirillum amazonense Y1, a micro-aerobic and acid-tolerant nitrogen fixer, and analyzed the growth and dry matter production and changes of nitrogen and phosphorus quantity of the plant during the growing period. The inoculation of associative N-fixing bacgteria increased the growth of height, leaf area, dry weight and total nitrogen quantity of the plant by 15.4%, 65.4%, 33.7% and 38.0%, respectively, on the day of 56th after sowing. Especially the inoculation of A. amazonense Y1 showed two to three-fold accumulation of phosphorus in each organ of plant. The associative bacteria accelerated the growth of the under ground parts more than those of the upper ground parts of corn plant, and caused decrease in T/R ratios.