• Journal of Korea Port Economic Association
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• v.23 no.4
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• pp.49-69
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• 2007

The purpose of this study is to analyze contribution factors of economic growth through growth accounting analysis in Korean port-logistics industry. Comparing with the average level of entire industry for 1990-2003, the contributions of total factor productivity and labor in port-logistics industry were high, but that of capital stock was very low. The pattern of growth in Korean port-logistics industry has greatly changed before and after Korean financial crisis. Before the 1997 financial crisis, the economic growth rate of port-logistics industry was 14.1%, which is higher than that of the whole industries, 7.7% for 1990-1998. Main contribution factors of the economic growth rate were the growth of capital stock and productivity, but ratios of their contributions were relatively low and did not come up to that for the whole industry. After the financial crisis, annualized growth rate of GDP in port-logistics industry had rapidly declined at 5.4% for 1998-2003, which did not get to that of the entire industry (10.1%). The main contribution factors of the economic growth rate over the 1998-2003 period were capital stock 13.1%, labor 57.0 %, and total factor productivity 29.9 %, Such growth pattern as excess dependence on growth of labor brought reduction of the rate of economic growth with degradation of productivity growth in the Korean port-logistics industry.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.4
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• pp.82-89
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• 2012

In order to clarify the effect of overload on crack growth behaviors, fatigue tests for overload were carried out for round plain specimens of SM45C steel. In the experiment, typical semi-elliptical crack shape was found and further crack growth behaviors were tested. Using three types of single overload fatigue tests, Crack growth retardation phenomenon were examined. The growth rate of surface crack(da/dN) during retardation period was analyzed in terms of ${\Delta}K$ and ${\Delta}K_{eff}$. On the growth rate of surface crack analyzed by ${\Delta}K$, the dependence of overload stress levels appears. However, on the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a liner relationship between da/dN and ${\Delta}K_{eff}$ with narrow scatter band.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.6
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• pp.527-531
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• 2005

Fully coherent self-assembled InAs quantum dots(QDs) grown on Si (100) substrates by atmospheric pressure metalorganic chemical vapor deposition(APMOCVD) were grown and the effect of growth conditions such as growth rate and growth time on quantum dots' morphology such as densities and sizes was investigated. InAs QDs of 30 - 80 nm in diameters with densities in the range of (0.6 - 1.7) x $10^{10}\;cm^{-2}$ were achieved on Si substrates and InAs layer was changed from 2 dimensional growth to 3 dimensional one at a nominal thickness less than 0.48 ML. This is attributed to the higher ambient pressure of APMOCVD suppressing of In segregation from the 2 dimensional InAs layer. This In segregation looked to disturb the dot formation especially when the growth rate was low so that the dots became less dense and bigger as the growth rate was lower.

• Journal of Information Science Theory and Practice
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• v.3 no.3
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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.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.247-251
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• 1997

GaN films were grown on three differently oriented sapphire substates; (0001), (11-20), and (1-20). GaN films on the (0001) and (11-20) substates have a haxagonal structure and their growth rate was 0.6 $\mu\textrm{m}$/hr in both case. The film on the (1-102) substrate was too thin to identify its crystalline state. Growth rate was about the half of the others. Substrate orientation is one of the factor determining growth rate. The adhesion between GaN film and alumina substrate seems to be very good judging from the fractography.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.263-268
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• 1998

(100) ZnSe crystals with twin and grain free were grown by vapor transport method. The defect in (100) ZnSe crystals was investigated by FWHM of X-ray Rocking Curve. The growth rate and seed quality are the main parameters of the growth process to obtain the high quality ZnSe crystals. The geometric shape of the grown (100) ZnSe crystal is dependent on the shape of seed, isothermal line in furnace and the growth rate of each surface in crystal.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.495-500
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• 2001

The significant creep in copper takes place at relatively low temperature and applied stress. Thus the study on modeling of creep behavior using the copper should provide researchers with benefits such as time for the test. In this study, a test of creep crack growth regarding copper was performed at 400 and $500^{\circ}C$, and analyzed. As result, the crack growth rate at $500^{\circ}C$ turned out to be 10 times higher than that at $400^{\circ}C$ in terms of $C^*$, while the crack growth rate at $500^{\circ}C$ was several hundreds times higher than that at $400^{\circ}C$ in terms of K. Moreover, a linear relationship between the crack growth rate and $C^*$ at the same temperature was established.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.52-57
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• 2001

Fatigue crack growth behaviour of Ti-6A-4V alloy is investigated in air and salt solution environment at room temperature and $200^{\circ}C$. Fatigue crack growth rate is blown to be fast for the formation of corrosive product in hot salt environment. For the effect on corrosion fatigue crack growth behaviour of region II. fatigue crack growth rate in atmosphere had a little gap to both case, $200^{\circ}C$ and room temperature. However, it showed very fast tendency in salt corrosive atmosphere, and it was remarkably accelerated in $200^{\circ}C$ temperature salt environment. When $\Delta$K was approximately 30MPa(equation omitted), fatigue crack growth rate had a little difference between at room temperature and at $200^{\circ}C$ high temperature, however in case of salt corrosive environment the room temperature was 3.5 times Inter and $200^{\circ}C$ high temperature for 16 times than air environment respectively.

• Fisheries and Aquatic Sciences
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• v.24 no.12
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• pp.415-427
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• 2021

Wetland ecosystems act as natural freshwater purification systems, but their rich biodiversity is being threatened with the introduction of the non-native freshwater snail, Pomacea canaliculata. This study was conducted to measure the herbivory effects and growth rate of P. canaliculata on common macrophytes: Ipomoea aquatica, Ipomoea batatas, Pandanus amaryllifolius and Cucurma longa. In separate experiments, the macrophyte species were served as the snails' food as individual species and simultaneously. In the individual treatment, the growth pattern and rate were based on the snails' weight (mg/snail/day; n = 9) while the individual feeding consumption (mg/snail/day) was calculated from the leftover food. In the simultaneous treatment, the herbivory effects were evaluated as the feeding preference (%) from observations every two hours, while the total feeding consumption (mg) was calculated based on the food remaining after a 12-hour experiment (3 replicates: total n = 27). The results indicated that the growth pattern was significant for snails grazing on I. aquatica but not when other macrophyte species were eaten. The individual feeding consumption was higher when using I. aquatica than P. amaryllifolius but the growth rate for snails grazing on I. aquatica and P. amaryllifolius did not differ significantly. Meanwhile, the consumption of C. longa deterred the snails' growth rate. Although the snails consumed all the macrophytes in the individual experiment, when given the species simultaneously, the feeding preference and total feeding consumption were directed significantly more toward I. aquatica than P. amaryfollius and C. longa. We conclude that P. canaliculata is a generalist feeder given a limited choice of food but tends to show a strong feeding preference after being introduced to more food choices. These findings indicate that the introduction of P. canaliculata into wetland ecosystems may increase the herbivory effects on macrophytes, making these ecosystems vulnerable to the impact of eutrophication and biodiversity reduction.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.4
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• pp.375-381
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• 2011

The primary aim of this study is to investigate the probabilistic characteristics of the fatigue parameters that describe the fatigue crack growth behavior in magnesium alloy. Statistical fatigue crack propagation experiments have been performed on rolled AZ31 magnesium alloy CT specimens with different specimen thickness, load ratio, and maximum load at ambient temperature in a laboratory. Using the statistical fatigue data obtained from these experiments, the goodness-of-fit of the probability distribution of the fatigue behavior parameters is evaluated in this study by performing statistical analyses. The crack growth rate coefficient is a fatigue parameter having a very large COV(Coefficient of Variation), but the variation of a crack growth rate exponent is not substantial. It is considered that a crack growth rate exponent can be a material constant. It is also found that the best fit probability distribution of the parameters such as the crack growth rate coefficient and crack growth rate exponent for a magnesium alloy is a three-parameter Weibull distribution, and two-parameter Weibull distribution is a good distribution only for the crack growth rate coefficient.