• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.113-124
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• 2009

This study has attempted to calculate the intensity of illumination for the optimal growth environment of indoor plants after analyzing both damage to plant species and growth conditions as impacted by light conditions for the Kyobo Life Insurance greenhouse. The optical intensity of illumination has been estimated after investigating the problems of growth conditions based on an analysis of illumination by light condition, dead tree replacement cycle(weeks) and rate of damage of plant species. According to the investigation of illumination, the lowest difference was observed between the shaded spot in the south(531lux) and the sunny spot(602lux) while the largest difference(nearly 500lux) was detected between the shaded spot in the central area(210lux) and the sunny spot(782lux). According to an analysis of dead trees from 1990 to 2004, in terms of dead tree replacement cycle, Viburnum awabuki was the highest(161weeks), followed by Phyllostachys spp.(84weeks), Camellia japonica and Ternstroemia japonica(40weeks). Regardless of plant species, damage rate of plant were lower in the shaded spot and higher in the sunny spot. According to correlation and regression analyses with the intensity of illumination as an independent variable and the damage rate of plant species as a dependent variable, the damage rate of plant species increased as the intensity of illumination decreased. A dramatic decline in the rate of damage was observed at $500{\sim}600lux$. At 700lux, it reached the lowest level.

• Journal of the Korean Society for Heat Treatment
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• v.5 no.1
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• pp.41-49
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• 1992

The effects of alloying elements on the superplastic properties of Al-Li based alloys had been investigated. The intermediate thermo-mechanical treated (ITMT) Al-2.0wt%Li, Al-2.0wt%Li-1.0wt%Mg, Al-2.0wt%Li-0.12wt%Zr and Al-2.0wt%Li-1.2wt%Cu-1.0wt%Mg-0.12wt%Zr alloys were tested in tension at various temperature (400, 450, 500 and $550^{\circ}C$) and strain rate($6.7{\times}10^{-3}$, $1.0{\times}10^{-2}$, $1.6{\times}10^{-2}$ and $5.0{\times}10^{-2}/sec$). The results were as follows : The superplasticity in binary, ternary and pentanary alloys appeared at 500 to $550^{\circ}C$, and good strain rate for superplasticity. $1.6{\times}10^{-2}/sec{\sim}1.0{\times}10^{-2}/sec$ for a binary alloy and $1.0{\times}10^{-2}/sec{\sim}6.7{\times}10^{-3}/sec$ for ternary and pentanary alloys. A Zr-added ternary alloy had best value of elongation (730%) in four alloys at $550^{\circ}C$ of tension temperature and $1.0{\times}10^{-2}/sec$ of strain rate. The strain rate was greatly dependent on tension temperature and true strain rate was more than 1.0 at all test temperature and strain rate. In binary and Mg-added teranry alloys. the necks were slightly formed and their fracture surface had lips shape, but Zr-added ternary and pentanary alloy fractured along the grain boundary without necking. Their dislocations moved to grain boundary during superplasticity deformation and arranged perpendicular to grain boundary. Super plastic deformation was made by grain boundary slip of dislocation slip creep and model of core and mantle.

• Journal of Energy Engineering
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• v.10 no.3
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• pp.206-213
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• 2001

Gasification kinetics of an Indonesian sub-bituminous coal-char with $CO_2$at elevated pressure was investigated with a pressurised drop tube furnace reactor. The effects of reaction temperature (900~140$0^{\circ}C$), partial pressure of carbon dioxide (0.1~0.5 MPa), and total system pressure (0.5, 0.7, 1.0, 1.5MPa) on gasification rate of the coal char with $CO_2$have been determined. It was found that the gasification rate was dependent on the total system pressure with the same partial pressure and temperature. The $n^{th}$ order rate equation (R=k $P^{g}$ $_{asn}$) was modified to be R=k $P^{g}$ $_{asn}$ $P^{m}$ $_{total}$ to describe the gasification rate where the total system pressure was changed. The gasification reaction rate of char-$CO_2$at high temperature and elevated pressure may be expressed as dX/dt=(174.1)exp(-71.5/RT)( $P_{CO2}$)0.40( $P_{total}$ )0.65(1-X)$^{2}$ 3/.X> 3/.

• KDI Journal of Economic Policy
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• v.32 no.2
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• pp.1-26
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• 2010

This paper empirically examines whether Korean monetary policy is independent of U.S. monetary policy during the post-crisis period in which capital account is liberalized and floating exchange rate regime is adopted and during the pre-crisis period in which capital mobility is restricted and tightly managed exchange rate regime is adopted. Before capital account liberalization, monetary autonomy can be achieved in view of the trillema, even under tightly managed exchange rate regime, as capital mobility is restricted. On the other hand, for the period after capital account liberalization, monetary autonomy can be also achieved in view of the trillema, as exchange rate stability is given up. Securing monetary autonomy, however, may not be easy under liberalized capital account for a small open economy like Korea. Huge capital movements can generate excessive instability in foreign exchange and asset markets. Strengthened international economic linkages may also be another factor to prevent monetary policy from being independent. Using block-exogenous structural VAR model, the effects of U.S. monetary policy shocks on Korean economy are examined. Empirical results show that Korean monetary policy is not independent of U.S. monetary policy for both periods before and after capital account liberalization. For the period after capital account liberalization, Korea does not seem to have implemented floating exchange rate policy in practice, which may lead Korean monetary policy to be dependent on U.S. monetary policy. For the period after capital account liberalization, portfolio flows respond dramatically to the U.S. monetary policy, which may also keep Korean monetary policy from being independent.

• The Korean Journal of Malacology
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• v.31 no.1
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• pp.35-41
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• 2015

In order to investigate the live food value of microalgae for efficacious rearing of larvae and spats of bivalve, we studied growth rates of four microalgal species (Isochrysis galbana, Pavlova lutheri, Chaetoceros simplex, Tetraselmis tetrathele) cultured in different environmental conditions. These include changes in temperatures (20, 25, 30 and $35^{\circ}C$), salinities (20, 25, 30 and 33 psu) and light intensities (60, 100 and $140{\mu}mol\;m^{-2}s^{-1}$). The growth rate of I. galbana was faster at $25^{\circ}C$ than that of $20^{\circ}C$. At $25^{\circ}C$ the highest growth rate of I. galbana was observed at 33 psu (0.413) and the lowest at 20 psu (0.368) in 10 days of culture (P < 0.05). The growth rate of I. galbana was lower at 25 psu (0.383) than that of 30 psu and higher than that of 20 psu (P < 0.05). Similar temperature and salinity-dependent changes were also found in P. lutheri and T. tetrathele. C. simplex showed faster growth rate at $30^{\circ}C$ than that of $25^{\circ}C$. The highest growth rate of C. simplex was observed at 33 psu (0.428) and the lowest at 20 psu (0.389) in 10 days of culture (P < 0.05). Upon exposure to the light with different intensities, all four microalgal species showed a significantly faster growth rate at $140{\mu}mol\;m^{-2}s^{-1}$ than at $100{\mu}mol\;m^{-2}s^{-1}$ (P < 0.05).

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.545-551
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• 1996

Water-vapor transmission rate and water-vapor permeability of carrageenan-based edible film with three different thicknesses of 0.05, 0.08 and 0.11 mm were measured to investigate the potential applicability of the films to powder foods at five different temperatures (20, 25, 30. 35 and $4^{\circ}C$) and three different relative humidities (50. 70 and 90% RH). Water-vapor transmission rate of the carrageenan-based film was gound to be 2.3 times higher than that of polyethylene (PE) film and water-vapor permeability of the film was 45-230 times higher than that of PE film. Water-ydpor permeability of the film seemed to increase linearly with the film thicknees like other hydrophilic edible films. Water-vapor transmission rate were found to be dependent on the temperature. Activation energies of the water-vapor transmission rate of the film were found to be between 7.898 and 12.8702 kj/mol depending on the film thickness. The water-vapor transmission rate of the film showed the typical kinetic compensation effect between activation energies and preexponential factors. which was proved by the linear increase in the value of logarithms of preecponential factor.

• Journal of Radiation Protection and Research
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• v.37 no.3
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• pp.159-166
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• 2012

The present study was performed to investigate the toxicity of low-dose-rate irradiation in BALB/c mice. Twenty mice of each sex were randomly assigned to four groups of five mice each and were exposed to 0 (sham), 0.02, 0.2, or 2 Gy, equivalents to low-dose-rate irradiation to 3.49 $mGy{\cdot}h^{-1}$. Urine, blood, and blood biochemistry were analyzed, and organ weight was measured. The low-dose-rate irradiation did not induce any toxicologically significant changes in mortality, clinical signs, body weight, food and water consumption, urinalysis, and serum biochemistry. However, the weights of reproductive organs including the testis, ovary, and uterus decreased in a dose-dependent manner. Irradiation at 2 Gy significantly decreased the testis, ovary, and uterus weights, but did not change the weights of other organs. There were no adverse effects on hematology in any irradiated group and only the number of neutrophils increased dose dependently. The low-dose-rate irradiation exposure did not cause adverse effects in mice at dose levels of 2 Gy or less, but the reproductive systems of male and female mice showed toxic effects.

• Journal of the Korea Society of Computer and Information
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• v.16 no.7
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• pp.183-190
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• 2011

Loan amount of housing mortgage is composed of various factors. This study paper studies focuses on estimating the determinants of a loan amount of housing mortgage. The region for analysis consist of seven groups, that is, metropolitan city (such as Busan, Daegu, Incheon, Gwangiu, Daejeon, Ulsan.) and Seoul. Analyzing period be formed over a 45 time points(2007. 01.~ 2010. 09). In this paper the dependent variable setting up loan amount of housing mortgage, explanatory(independent) variables are composed of the consumer price index, unemployment rate, average monthly household income per household, expenditure rate of health care, composite stock price index and overdue rate of household loans for commercial bank. In looking at the factors which determine loan amount of housing mortgage, evidence was produced supporting the hypothesis that there is a significant positive relationship between the consumer price index and unemployment rate. The study also produced evidence supporting the view that there is a significant negative relationship between expenditure rate of health care. The study found that average monthly household income per household, expenditure, composite stock price index and overdue rate of household loans for commercial bank were not significant variables. The implications of these findings are discussed for further research.

• Korean Journal of Health Education and Promotion
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• v.18 no.1
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• pp.61-78
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• 2001

The purpose of this research was to find out plans to promote the fulfillment of the breast self-examination and breast cancer screening, which is preventive health behavior about women's having breast cancer exam in some part of our country with searching for the primary causes which have an effect on their fulfillment. The subjects of the study were 540 literate volunteers who were of age from 20 to 69 and who visited 8 health centers in Taegu. The survey research was made through questionares in the 8 health centers in Taegu from the 15th to the 30th of September, 1998. Based on Becker's health belief model asking medical staff's opinions with bibliographies, the major findings from the survey was as follow. The fulfillment rate of the breast self-examination and the breast cancer screening was 37.8％(204 subjects), 27.6％ (149 subjects) each. Getting breast self-exam varied significantly depending on subject's age, income of family, religion, occupation and the number of children. As far as the breast cancer screening was concerned, there was remarkably significant difference in accordance with their age, marital status, religion, occupation, income of family, the number of children, ways of nursing and parturition age of the first baby. The subjects in their forties accounted for the highest rate. Based on the fulfillment of the breast self-examination and the breast cancer screening, the average points of all the variables presented from the health belief as well as the points of the susceptibility, seriousness, benefits, knowledge and level of health concern of interest in health were significantly higher than the points of non-fulfillment of them in the statistical analysis whereas the barriers was lower than them. In consequence of the multiple-logistic regression analysis putting the breast self-examination and the breast cancer screening in dependent variables, occupation, knowledge, seriousness, benefits, barriers and cues to action had significant effects on breast self-examination against breast cancer. Looking more attainments, thinking diseases more seriously, feeling more usefulness and there being any patient around with breast cancer led to the higher rate of the breast self-examination against it. On the other hand, feeling more impedition as well as housewives caused the lower rate of it. The breast cancer screening was significantly affected by age, sensitivity, usefulness, impedition and behavior momentum as well. The cases who are older, feeling more sensitivity against breast cancer, more usefulness of the examination and where any patient around, the fulfillment rate was higher. Contrarily the more impedition they felt, the lower the fulfillment rate was. Accordingly, the study of the causes, which have significant effects on the fulfillment of the self-examination and the breast cancer screening in order to find it in an early stage, and the development of health education programs as well as proper education for public health through carrying on campaigns and stepping up public relations must be indispensable.

• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.853-862
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• 2017

In this study, we analyse the determinants of the youth employment rate of public agencies and local public enterprises. On the other hand the youth employment rate contains information of the youth employment rate and the size of the youth employment. We use pooled tobit model and panel tobit model since dependent variable is a censored form observed only in a certain area. The results of the analysis are summarized as follows. First, the panel tobit model is more statistically significant as compared to the combined tobit model. Second, the youth employment rate is more statistically significantly higher in 2014 and 2015 than in 2011. Third, the youth employment rate in public enterprises is more statistically significantly higher than that in local public agencies. Finally, the higher the average wage is, the lower the youth employment ratio is.