• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6203-6207
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• 2012

The aim of the study was to develop an objective measurement tool, which could measure radiation safety regulations as an advanced research to draw evidentiary conclusions for the rationalization of radiation safety regulations as organizations continuously increase consumption of radiation material. The survey was based on the contents of Vol 1~21 of US NRC NUREG 1556 (Consolidated Guidance About Materials Licenses) and material from the Nuclear Safety Act which was based on radiation safety managers who are responsible for about 10% of the domestic registered organizations for radiation usage. As a result of the analysis, 3 main causes were extracted based on 20 questions. Each causes were named as Cause 1: 'Radioactive Safety Regulations Requirements', Cause 2: 'Compatibility of Actual Safety Regulation', and Cause 3: 'RI/RG radiation Source Classification' respectively. The dispersal explanations of each causes were explained in total of 60.417% by 40.140% of Cause 1, 13.721% of Cause 2, and Cause 3 for 6.556% If radiation safety regulation standards are drawn using the radiation safety regulation measurement tool, which is suggested in this study, this could be not only comply with international standards but also could be used to propose a practical standard to domestic radiation safety managers.

• Journal of Korea Port Economic Association
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• v.37 no.4
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• pp.161-173
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• 2021

The shipping industry plummeted and was depressed due to the global economic crisis caused by the bankruptcy of Lehman Brothers in the US in 2008. In 2020, the shipping market also suffered from a collapse in the unstable global economic situation due to the COVID-19 pandemic, but unexpectedly, it changed to an upward trend from the end of 2020, and in 2021, it exceeded the market of the boom period of 2008. According to the Clarksons report published in May 2021, the decrease in cargo volume due to the COVID-19 pandemic in 2020 has returned to the pre-corona level by the end of 2020, and the tramper bulk carrier capacity of 103~104% of the Panamax has been in the ports due to congestion. Earnings across the bulker segments have risen to ten-year highs in recent months. In this study, as factors affecting BDI, the capacity and congestion ratio of Cape and Panamax ships on the supply side, iron ore and coal seaborne tonnge on the demand side and Granger causality test, IRF(Impulse Response Function) and FEVD(Forecast Error Variance Decomposition) were performed using VAR model to analyze the impact on BDI by congestion caused by strengthen quarantine at the port due to the COVID-19 pandemic and the loading and discharging operation delay due to the infection of the stevedore, etc and to predict the shipping market after the pandemic. As a result of the Granger causality test of variables and BDI using time series data from January 2016 to July 2021, causality was found in the Fleet and Congestion variables, and as a result of the Impulse Response Function, Congestion variable was found to have significant at both upper and lower limit of the confidence interval. As a result of the Forecast Error Variance Decomposition, Congestion variable showed an explanatory power upto 25% for the change in BDI. If the congestion in ports decreases after With Corona, it is expected that there is down-risk in the shipping market. The COVID-19 pandemic occurred not from economic factors but from an ecological factor by the pandemic is different from the past economic crisis. It is necessary to analyze from a different point of view than the past economic crisis. This study has meaningful to analyze the causality and explanatory power of Congestion factor by pandemic.

• The Korean Journal of Applied Statistics
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• v.34 no.4
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• pp.589-597
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• 2021

In simple and multiple regression, there is a difference in the meaning of regression coefficients, and not only are the estimates of regression coefficients different, but they also have different signs. Understanding the relative contribution of explanatory variables in a regression model is an important part of regression analysis. In a standardized regression model, the regression coefficient can be interpreted as the change in the response variable with respect to the standard deviation when the explanatory variable increases by the standard deviation in a situation where the values of the explanatory variables other than the corresponding explanatory variable are fixed. However, the size of the standardized regression coefficient is not a proper measure of the relative importance of each explanatory variable. In this paper, the estimator of the regression coefficient in multiple regression is expressed as a function of the correlation coefficient and the coefficient of determination. Furthermore, it is considered in terms of the effect of an additional explanatory variable and additional increase in the coefficient of determination. We also explore the relationship between estimates of regression coefficients and correlation coefficients in various plots. These results are specifically applied when there are two explanatory variables.

• The Korean Journal of Financial Management
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• v.27 no.2
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• pp.169-204
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• 2010

This paper examines the dynamic relationship between fund flow and market risk at the aggregate level and explores whether sudden sharp changes in fund flow (fund run) can cause a systemic risk in the Korean financial markets. We use daily and weekly data and regression and VAR analysis. Main results of the paper are as follows: First, in the stock market, a concurrent and a lagged unexpected fund flows have a positive relationship with market volatility. A positive shock in fund flow predicts an increase in stock market volatility. In the bond market, an unexpected fund flow has a negative relationship with the default risk premium, but a positive relationship with the term premium. And an unexpected fund flow of the money market fund has a negative relationship with the liquidy risk, but the explanatory power is very low. Second, for examining whether changes in fund flow induce a systemic risk, we construct a spillover index based on the forecast error variance decomposition of VAR model. A spillover index represents that how much the shock in fund flow can explain the change of market risk in a market. In general, explanatory powers from spillover indexes are so fluctuant and low. In the stock market, the impact of shocks in fund flow on market risk is relatively high and persistent during the period from the end of 2007 to 2008, which is the subprime-mortgage crisis period. In bond market, since the end of 2008, the impact of shocks in fund flow spreads to default risk continually, while in the money market, such a systematic effect doesn't take place. The persistent patterns of spillover effect appearing around a certain period in the stock market and the bond market suggest that the shock to the unexpected fund flow may increase the market risk and can be a cause of systemic risk in the financial markets. However, summarizing the results of regression and VAR model analysis, and considering the very low explanatory power of spillover index analysis, we can conclude that changes in fund flow have a very limited power in explaining changes in market risk and it is not very likely to induce the systemic risk by a fund run in the Korean financial markets.

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.591-600
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• 2022

This study examined the participation of the people with stroke living in the community in terms of productivity, leisure, and social domain, and identified the effect on disability acceptance and anxiety. For data collection, from October 2018 to January 2019, data on disability acceptance, anxiety, and participation were collected from 192 people with stroke who used welfare centers and community services. For general characteristics, t-test and one-way ANOVA were used to compare participation according to descriptive statistics and general characteristics. Pearson correlation analysis was used for correlation between variables, and multiple regression analysis was used to identify causality. As the result, factors affecting the productivity of participation were labor(β=.28, p<.001), de-emphasis on disability salience(β=.14, p<.05), compensatory(β=.22, p<.01), and subjective anxiety(β=-.35, p<.05), and the explanatory power was 33%(F=9.44, p<.001). Leisure was expressed as self-satisfaction with disability(β=.18, p<.05) and the compensatory(β=.18, p<.05), and had an explanatory power of 23%(F=6.32, p<.001). Social activity was labor(β=.19, p<.01), and subjective anxiety(β=-.51, p<.05), which showed 23%(F=6.05, p<.001) of explanatory power. This suggests the importance of psychosocial factors for a changed life after the onset of a stroke, and a practical approach is needed to construct and apply programs to improve participation.

• The Korean Journal of Applied Statistics
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• v.24 no.4
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• pp.567-573
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• 2011

This study develops a predictive model for household water end-uses based on data that have measured household characteristics, housing characteristics and other items, surveyed over 3 years in Korea. However, the measured data was left-skewed and it was not fitted to normal distribution. The parameter estimate were biased when using a multiple regression model. In addition, the results of the testing for the model were usually of significance due to the tiny residual from a large number of observations. In order to solve the problem, we suggested log-normal regression model and Weibull regression model as alternatives. The results of this study can be utilized in the planning stages of water and waste water facilities.

• Journal of the Korea Computer Industry Society
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• v.8 no.2
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• pp.73-80
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• 2007

In this reaearch, our goal is to find the representative adjectives which express the sensitivity for wall paper. We want to make a model which can explain the whole by using the representative adjectives. We got the adjectives through the questionnaire survey, field survey, and internet survey. To find the representative adjectives, we used modified factor analysis. The factor analysis used in preceding research can not control the individual difference of sensitivity, because the distribution information of data is concentrated into the mean. So, we used the modified factor analysis to control it. The experimental result showed that the reduced factors could account about 79.5% when the number of factor are three. The individual difference of sensitivity was reflected in some adjectives. This result can be used to make a recommending model for wallpaper.

• Proceedings of the Population Association of Korea Conference
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• 2006.12a
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• pp.131-152
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• 2006

This study examines the causal mechanisms of low fertility and regional differentials in Korea. Utilizing the 2005 census and the 2005 vital statistics, and labor statistics at the regional level, major variables were calculated for administrative units of 234 'Gu's, 'Si's and 'Gun's. Gender equity orientation, labor market insecurity and family formation were hypothesized as key factors of recent decline in Korean fertility. This study first presents four maps of gender equity orientation, labor market insecurity, family formation and fertility. Then ANOVA and path analysis were carried out in an effort to generalize the causal mechanisms. Results of analysis reveal that gender equity orientation has played a central role in the second fertility transition in Korea. In metropolitan regions, however, labor market insecurity is found to have a significant influence on the level of family formation and fertility. Family formation also turns out to be an important intermediate variable of fertility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.86-94
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• 2016

The purpose of this study was to investigate the factors influencing empathy with the elderly in student nurses and to provide the basic data on nursing education to improve empathy. Data were collected from 277 student nurses in B and C cities and analyzed by the t-test, ANOVA, Pearson correlation coefficients, and multiple regression using SPSS WIN 20.0. The degree of empathy with the elderly in the student nurses was $214.66{\pm}22.72$. There were positive correlations between empathy and attitude of the elderly (r=.224, p<.001) and between empathy and facilitative communication (r=.346, p<.001), and these factors explained 15.4% of the empathy with the elderly. These results indicated that it is necessary to develop a nursing education program and curriculum for increasing empathy in student nurses.

• Journal of Industrial Convergence
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• v.20 no.4
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• pp.39-46
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• 2022

This descriptive survey study identified the factors influencing the abiliy of healthcare perceived by high school students. The survey was conducted from May 7, 2020, to Sep. 17, 2020 for 119 high school students in City D. SPSS WIN 22.0 program was used to for t-test and one-way ANOVA with Pearson's correlation coefficients and hierarchical regression analysis. The ability of healthcare perceived by high school students had a static correlation with the sub-domains of family function, that is, family cohesion(r=.65, p<.001) and family adaptability(r=.54, p<.001). For male students(β=.17, p=.012), those who reported a high level of perceived health status showed a high level of ability of healthcare(β=.25, p<.001). Significant influencing factors on high school students' health management ability were identified as gender (β=.17), their own health status perception (β=.23), and family cohesion (β=.45), and the explanatory power of the model was 50%. appear. Further research is hereby suggested for validation of the mediating role and effects of health care education programs to improve the family function perceived by high school students, encourage their practicing of health care management and help them to enter into healthy adulthood.