• Fire Science and Engineering
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• v.31 no.5
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• pp.19-27
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• 2017

The effects of changes in area and location of fire source, fire growth rate, and volume of compartment on the major fire characteristics, including heat release rate, in closed compartment fires were examined. To this end, a fire simulation using Fire Dynamics Simulator (FDS) was performed for ISO 9705 room with a closed opening. As main result, it was found that the changes in the area and location of fire source did not significantly affect the thermal and chemical characteristics inside the compartment, such as maximum heat release rate, total heat release, maximum temperature at upper layeras well as species concentrations. However, increasinthe fire growth rate and volume of compartment resulted in increase of the maximum heat release rate and total heat release, decrease in the limiting oxygen concentration and increase in the maximum CO concentration. Finally, a methodology for the application of fire growth curves to closed compartment fires was proposed by deriving the correlation of the maximum heat release rate expressed as a function of the fire growth rate and the volume ratio of compartment based on the ISO 9705 room.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.345-352
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• 1998

A Korean endemic and evergreen small tree ' Dendropanax morbifera $L_{EV}$.(Araliaceae)' is a component of evergreen forest and mainly idstributein sourthern region and islands in Korea. A local population of D. morbifera which is located between evergreen and deciduous forest within 50m x 50m quadrate was investigated to ascertain the change of population structure, emergence and growth dynamics of seedlings and saplings, and pattern of spatial distribution by the temproal and spatial expansion of population . The result of analysis of population structure by Importnace Value(IV), evergreen forest showed a high species diversity of evergreen tree species such as Cinnamomum japonicum, Machilus japonica, Neolitsea serica, Daphniphyllum macropodum, Ligustrum japonicum, and etc, in middle and under story than in upper story where Camelia japonica and Quercus acuta were dominant. And in conterminous deciduous fores, the major component of evergreen forest in this region, Camellia japonica, Quercus acuta, evergreen tree of Lauraceae and etc. were abundant in only under story. IV of D. morbifera differed from among three story. In comparative analysis of emergence and growth dynamics of D. morbifera seedlings and saplings between evergreen and deciduous forest, emergece and density of seedlings were significantly greater in evergreen than in deciduous forest, and growth of height and basal diameter of seedlings and saplings were slightly larger in evergreen than in deciduous forest. The spatial distribution patterns by Moristia's index mapping of indivuduals using a lattice method of XY axis within this population showed that seedlings(age up to 2 years) and saplings (age>2 years and height<1m) both evergreen and deciduous forest were more or less aggregated apart from mature trees, and thougth intermediate trees(height>1m and dbh<10cm) had a aggregated distribution pattern, mature trees(dbh>10cm were uniform. In conclusion , the expansion of D. morbfera population from evergreen to deciduous forest accompanied with a mumber of evergreen woody species, and also, emergence and recruitment, and growth of seedlings were greatly influenced moisture and canopy by around community structure.

• International Journal of Computer Science & Network Security
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• v.22 no.3
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• pp.67-76
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• 2022

COVID-19 struck labor markets around the world, exposing and exacerbating the gender inequalities within the human capital structure. The last, in its turn, jeopardizes the return of the national economies to the growth trajectory undermined by pandemic impact. The authors assume that COVID-19 disproportionately affected the employment rates of women and men, which led to increased gender inequality in the labor market, which, in turn, affected GDP growth rates in the EU. To prove this hypothesis two research questions are discovered: 1) whether there was a different correlation between the number of COVID-19 cases in the EU and indicators of the labor market for women and men; and 2) whether there was a link between the growth of gender inequality in the EU labor market and the GDP dynamics in these countries. The analysis of the correlation between the number of cases of COVID-19 and indicators of the labor market in the EU revealed faster growth of women's unemployment rates compared to men's ones as the COVID-19 incidence unfolded. Multiple linear regression and factor analysis have been used to investigate the influence of gender inequality in the labor market on GDP dynamics. Despite the methodological limitations, the proposed model is both a sound argument and an analytical basis in favor of gender-responsive economic recovery backed by the systematic and consistent gender equality policy of a government.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.144-150
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• 2003

Reproductive biology and population dynamics of Latreutes planirostris were investigated on the south western waters of Korea from June 2001 to May 2002. This paper describes sex ratio, population growth, and reproductive aspects of Latreutes planirostris. Brood size was an isometric function of female carapace length. Based on dry weight, reproduction effort (mass of eggs/mass of female) averaged 0.23. Ovarian examination showed that there was significantly higher gonadosomatic index from May to September, with a peak in June. Statistical analysis revealed that the ovarian dry weight of females with eyed eggs was significantly higher than that of those with non-eyed eggs. This suggests that females were potentially consecutive breeders. Sex ratio showed that female is more numerous than male. Growth parameters mortality and recruitment were estimated by monthly length-frequency data. Growth parameters were estimated, using the seasonalized von Bertalanffy growth function model $(L\infty\;=\;12.70\;mm\;CL,\;K\;=\;0.87yr^{-1},\;C\;=\;0.96,\;WP\;=\;0.59)$. The recruitment pattern was twice a year.

• Proceedings of the Korean Vacuum Society Conference
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• 2009.08a
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• pp.49-49
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• 2009

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.08a
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• pp.29-29
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.82.2-82
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• 1998

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.381-383
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• 1999

First topic of this paper aims to clarify how oxygen and heat transfer in silicon melt under cusp-shaped magnetic fields. We obtained asymmetric temperature distribution by using time dependent and three-dimensional calculation. Second topic is study on molecular dynamics simulation, which was carried out to estimate diffusion constants of oxygen in silicon melt.

• Journal of Technology Innovation
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• v.17 no.1
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• pp.69-95
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• 2009

This paper examines the motives for location decisions of startups and dynamics of cluster growth. Because the location decision is intrinsically strategic choice by entrepreneurs, it is an interplay of three critical forces; cost-benefit of the choice, R&D ability of new entrants, and R&D capability of incumbents in clusters. The effect of knowledge spillovers influences the cluster growth like a double-edge sword; both a positive effect of technology learning and a negative effect of knowledge de-learning. Using data on 710 bio-tech venture firms in Korea, this paper tests the hypotheses about the factors influencing the growth of the cluster. The empirical analyses suggested that early entrepreneurial activity in the clustered regions were important, however other factors such as the organizational legacy, internal dynamics inside a cluster, and the existence of cooperation norm in the cluster, affected long term viability of the cluster.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.431-439
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• 2012

Dissipative particle dynamics (DPD) was carried out to study the nucleation and crystal growth process of $CeO_2$ nanoparticles in different alcohol aqueous solutions. The results showed that the nucleation and crystal growth process of $CeO_2$ can be classified into three stages: nuclei growth, crystal stabilization and crystal aggregation except the initial induction stage, which could be reproduced by collecting simulation results after different simulation time. Properly selecting the sizes of $CeO_2$ and water bead was crucial in the simulation system. The influence of alcohol type and content in solutions, and precipitation temperature on the particle dimension were investigated in detail and compared with the experimental results. The consistency between simulation results and experimental data verify that the simulation can reproduce the macroscopic particle aggregation process. The effect of solvent on the nucleation and crystal growth of $CeO_2$ nanoparticles are different at three stages and can not be simply described by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory or nucleation thermodynamics theory. Our work demonstrated that DPD methods can be applied to study nanoparticle forming process.