• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.140-145
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• 2012

The purpose of this study is to understand the change of impression by comparing the uniformity lighting with the compound lighting. In previous study, we proposed a light controlling method to harmonize daylight from a window and artificial lights from a ceiling and obtained the results to support our method. We referred this method as the Adjusted Compound-Lighting Model (AC Model). The model claims that lighting in a room with a side-window are perceived as harmonious when the overall light distribution in the room is well approximated by a compound of lights from the window and the entire ceiling. The experiment is carried out with the scaled-models and mock-up spaces that were supposed to be an office space. One is lit by the uniform lighting and the other by the compound lighting in each experimental space. In order to present varying illuminance distributions, thetwo variables were used in this study. One was the ratio of thelight from the window and ceiling in the standard and evaluation box. The standard box was provided by the ratio of 20% to 40% from the window and 80% to 60% from the ceiling as two lighting ratio patterns [Wu20(=Cu80) and Wu40(=Cu60)]. And the evaluation box was provided by the light ratio of 0% to 40 from the window and 100% to 60% from the ceiling [Wcp0(=Ccp100), Wcp20(=Ccp80) and Wcp40(=Ccp60)]. The other variable was themean illuminance level in both boxes. Two level of mean illuminance (700lx and 300lx) were used in this experiment. Each lighting condition was established at equal horizontal mean illuminance level, held constant near 700lx or 300lx in both boxes. Both of them were similar in the shape of distribution when there were same ratios of lights from the window and the ceiling. Subjects were asked to evaluate the point of difference by semantic differential rating on their overall impression after comparing with two rooms. The results showed that the impressions of compound lighting were more positive score than that of uniformity lighting on the items of 'dim-bright', 'dislike-like', 'artificial-natural' and 'closed-open', and that there was no significant difference in impressions between two spaces on other items.

• Korean Journal of Plant Tissue Culture
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• v.24 no.4
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• pp.239-256
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• 1997

Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

• The Korean Journal of Financial Management
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• v.26 no.4
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• pp.1-34
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• 2009

We test the effect of corporate cash holdings on firm value by using the KOSPI listed firms over the period between 2002 and 2007 from the agency theories perspective, which has not been the central interest of prior studies. Unlike existing studies, using the manager's ownership ratio or foreign investor's shareholder ratio as a proxy variable for agency costs, we use the individual firm's corporate governance scores by the KCGS to test the effect of agency costs on the value of firm's cash holdings. We find that a firm value is positively related with its cash holdings. We also find that a firm with good corporate governance tends to experience a higher value of its cash holdings, compared with a firm with bad corporate governance. These results are consistent even after controlling for the endogeneity problems between corporate governance and firm value, strongly supporting the agency theory of cash holdings. Therefore, a firm's cash holdings, even from liquidity or precautionary motives, could increase the firm cash value, as long as its managers' interest is shareholders' wealth maximization rather than their private benefits.

• Journal of Distribution Science
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• v.14 no.6
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• pp.75-80
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• 2016

Purpose - A growing demand for sustainability reporting has placed pressure on firms with non-financial information that affects firm valuation, growth, and development. In particular, a number of researchers have investigated various topics in Corporate Social Responsibility (CSR), non-financial information. Prior studies suggest that CSR may affect corporate outcomes like corporate reporting, financial performance, and disclosures. However, the results from prior studies are not clear whether CSR affects corporate outcomes. This is partially due to the measurement issues with CSR. In this study, we examine whether CSR affects the quality of corporate reporting, one of the popular measures in corporate outcomes. We find an evidence that CSR positively affects the quality of corporate reporting. Research design, data, and methodology - In this study, we collected a unique dataset of CSR from MSCI. Total 169 firms listed in the Korean Stock Exchange from 2011 to 2014 were collected and analysed with the detailed CSR reports. Using a correlation test, we found a weak association between CSR and the quality of corporate reporting. However, the regression tests provided a strong relationship between CSR and the quality of corporate reporting after controlling for other variables that may affect the quality of corporate reporting. Additionally, we calculated the t-statistics based on heteroskedaticity-consistent standard errors (White, 1980). Results - Before we run the regression test, we sort the measures of the two dependent variables into each rating of CSR (from AAA to CCC). The results indicate that the quality of corporate reporting measured by discretionary accruals and performance-matched discretionary accruals monotonically decrease as the CSR ratings increase. This supports our hypothesis. In the regression tests, the coefficient on MJDA (PMDA) is -0.183 (-0.173) and significant at the 5% level. We can interpret the results as CSR affecting the quality of corporate reporting in positive ways. Other coefficients on control variables are consistent with prior studies. For example, the coefficients on both LOSS and LEV are positive and significant at conventional level, meaning that firms with financial difficulty may harm their quality of corporate reporting. Conclusion - We found an evidence that CSR is positively associated with the quality of corporate reporting. This study contributes to the literature in various ways. First, this study extends the line of CSR research by providing additional evidence in the setting of ethical behaviors by managements. This is consistent with the hypothesis and supports the results of prior studies. Second, to the best of my knowledge, this is the first study using the MSCI CSR ratings. In contrast with prior studies using different measures of CSR, the MSCI CSR ratings allow us to provide in-depth analysis. Third, the additional measure of dependent variable (PMDA) allows us to improve the robustness of our results. Overall, the results provided this study to extend the findings in prior studies by providing incremental evidence.

• Applied Chemistry for Engineering
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• v.19 no.2
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• pp.185-190
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• 2008

In order to increase the surface area of electrodes for electrosorption, porous carbon electrodes were fabricated by a wet phase inversion method. A carbon slurry consisting of a mixture of activated carbon powder (ACP), polyvinylidene fluoride (PVdF), and N-methyl-2-pyrrolidone (NMP) as a solvent was cast directly on a graphite sheet. The cast film was then immersed in pure water for phase inversion. The physical and electrochemical properties of the electrodes were investigated using scanning electron microscopy (SEM), porosimetry, and cyclic voltammetry. The SEM images verified that the pores of various sizes were formed uniformly on the electrode surface. The average pore sizes determined for the electrodes fabricated with various NMP contents ranged from 64.2 to 82.4 nm and the size increased as the NMP content increased. All of the voltammograms showed a typical behavior of charging and discharging characteristic at the electric double layer. The electrical capacitance ranged from 3.88 to $5.87F/cm^2$ depending on the NMP contents, and the electrical capacitance increased as the solvent content decreased. The experimental results showed that the solvent content is an important variable controlling pore size and ultimately the capacitance of the electrode.

• Journal of The Korean Association For Science Education
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• v.19 no.1
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• pp.117-127
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• 1999

The present study investigated Korean and the US college students' scientific reasoning skills involving hypothesis-testing skills and tested the hypothesis that hypothesis-testing skills are more advanced ones than other scientific reasoning skills investigated in this study. Seven hundred and seventy-four(774) Korean and five hundred and sixty-eight(568) the US students were sampled in university level. The Test of Scientific Reasoning was used as a scientific reasoning test. The test is consisted of two conservational reasoning, two proportional reasoning, one pendulum, two probability reasoning, two controlling variable, one correlational reasoning, and two hypothesis-testing reasoning tasks. Korean students showed a significant higher score in proportional and probability reasoning tasks than the US students. However, the Korean showed a significant lower score in conservation and correlation reasoning tasks than their American counterparts. Further, Korean and the US college students showed a notably poor performance in hypothesis-testing skills comparing with other scientific reasoning skills, which supported the hypothesis that hypothesis-testing skills are more advanced ones than other scientific reasoning skills. In addition, the Korean showed a severe deficiency in candle-burning task which required the skill that students have to design a scientific test-procedure to test theoretical hypotheses. This study also discussed on the educational implications of the results of the present study.

• Korea journal of population studies
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• v.29 no.1
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• pp.57-70
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• 2006

Patterns and changes of marriage have drawn much attention as they have been pointed out a key factor of low fertility. Nonetheless, systematic studies on marriage have been quite limited. This study, using recent nationwide survey on marriage and fertility, attempts to explain whether and how intention of marriage would differ between never married men and never married women. The logit regression analysis reveals that the likelihood of planning marriage between both sexes are still different even after controlling demographic characteristics, economic status, household and family background, and attitudes toward sex and premarital cohabitation. Furthermore, important factors affecting the likelihood of planning marriage turns out to be different between men and women. For instance, men with a job is more likely than men without a job to plan marriage. However, for women, the effect of having a job is not found. Such result, with other sex differential effects of living arrangement and attitudinal variable, suggests that the mechanism through which men and women transit from singlehood to marriage would differ. More attention on gender differential should be paid in developing conceptual arguments and conducting empirical analysis regarding marriage and its related topics.

• Tuberculosis and Respiratory Diseases
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• v.64 no.3
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• pp.219-223
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• 2008

Pheochromocytoma is derived from the chromaffin tissue. The typical finding of pheochromocytoma is paroxysmal hypertension accompanied with various signs and symptoms that are due to the excess of catecholamines or other bioactive substances. Yet the diagnosis is sometimes difficult to make because its clinical presentation is quite variable. Especially, hemoptysis is a very rare symptom, so the diagnosis is often missed or delayed. Without making the correct diagnosis and then subsequently administering treatment, the condition may be fatal. We herein report on a 68 year-old woman who was admitted because of abdominal pain and hemoptysis. The initial radiologic findings suggested pulmonary edema with alveolar hemorrhage. The urine catecholamine levels were elevated and she developed catecholamine-induced cardiomyopathy. We performed bronchial arterial embolization and we administered alpha blocker medication for controlling the hemoptysis and hypertension. After the temporary symptomatic improvement, her clinical course was aggravated by pneumonia and pulmonary edema. In spite of performing definitive surgery for pheochromocytoma, she died of postoperative hemodynamic instability.

• Journal of agricultural medicine and community health
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• v.38 no.1
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• pp.39-48
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• 2013

Objectives: This research was done to identify relationships among job stress, fatigue, job satisfaction, and commitment to organization in customized home health care nurses. Methods: Research participants were 130 nurses who worked in the customized home health care of 20 county in Gyeongnam province. Data collection for this descriptive correlational study was done at August 2010 using self report questionnaires, and analyzed using descriptive statistics, t-test, ANOVA, and we analyzed a four step approach in which several regression analyses were conducted and significance of the coefficients is examined at each step. Results: The results from step 1 showed that, the effect of each job stress was significantly related to job satisfaction. In step 2, the direct effect of commitment to organization on job satisfactions were all significant too. Step 3 analysis showed that the total effect of each job stress on commitment to organization symptoms was significant. Step 4 showed the results of controlling for mediating factor (job satisfaction): job demand and insecurity were significantly associated with commitment to organization(p<0.001), the finding supports that others were fully mediated by each job satisfaction, and, the job demand and insecurity were partially mediated by job satisfaction. Conclusion: Results of this research indicated that job stress in customized home health care nurses was the principal variable affecting job satisfaction and commitment to organization. Appropriate stress management strategies based on assessment of job demand and job security for these nurses lead to development of improved commitment to organization.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.15-21
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• 2005

Korean ginseng(Panax ginseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In transformation of ginseng with betain aldehyde dehydrogenase gene, compounds synthesized for controlling osmotic pressure such as proline, glycine, betaine, polyols and sugar were accumulated in cell for salt resistance in transgenic plants. 2 Agrobactgerium conjugants were acquired with bet A and bet B genes for solt resistant plants. A. tumefaciens MP90/pBetA and A. tumefaciens MP90/pBetB were recombined for increasing the tolerance to salt stress. To confirm the transformation of the binary vector, tobacco plant was transformed, and the transformant can grow on media containing high concentration of kanamycin. To identify NPT 11, BetA and BetB genes of the transformants, the band on the agarose was confirmed by PCR and RT-PCR techniques. The transformants of ginseng with bet A and bet B genes were acquired on the phytohormone free basic MS media containing only antibiotics and 1M mannitol used for selection of transgenic plant, but the transfomation efficiency for BetA and BetB was very low.