• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.525-535
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• 2018

If the frequency of a particular class is excessively higher than the frequency of other classes in the classification problem, data imbalance problems occur, which make machine learning distorted. Corporate bankruptcy prediction often suffers from data imbalance problems since the ratio of insolvent companies is generally very low, whereas the ratio of solvent companies is very high. To mitigate these problems, it is required to apply a proper sampling technique. Until now, oversampling techniques which adjust the class distribution of a data set by sampling minor class with replacement have popularly been used. However, they are a risk of overfitting. Under this background, this study proposes ROSE(Random Over Sampling Examples) technique which is proposed by Menardi and Torelli in 2014 for the effective corporate bankruptcy prediction. The ROSE technique creates new learning samples by synthesizing the samples for learning, so it leads to better prediction accuracy of the classifiers while avoiding the risk of overfitting. Specifically, our study proposes to combine the ROSE method with SVM(support vector machine), which is known as the best binary classifier. We applied the proposed method to a real-world bankruptcy prediction case of a Korean major bank, and compared its performance with other sampling techniques. Experimental results showed that ROSE contributed to the improvement of the prediction accuracy of SVM in bankruptcy prediction compared to other techniques, with statistical significance. These results shed a light on the fact that ROSE can be a good alternative for resolving data imbalance problems of the prediction problems in social science area other than bankruptcy prediction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3230-3242
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• 2015

In this study, in an attempt to elucidate the relevance and the association between AUDIT level and health related indices such as obesity-related indices (BMI, waist circumference, body fat percentage), serum liver-enzyme levels (AST, ALT, GGT, total bilirubin) and serum lipid levels (TC, TG, HDL-C, LDL-C), data about including results of health checkup examination and questionnaire from 558 male examinees of 30-79 years old, who received a comprehensive health examination in the health promotion center of a university hospital during the period of January 1 to December 31, 2012, was analysed. As a results, the distribution of AUDIT rating of subjects was Zone I 58.2%, Zone II 25.3%, Zone III 7.0%, and Zone IV 9.5%. And AUDIT levels have significant relevance with age, smoking, body fat, GGT and TG. Especially, for the waist circumference, GGT and TG, the odds ratio indicating abnormality significantly increased in the higher AUDIT groups (Zone II~Zone IV) than a low-grade group (Zone I). This suggests that drinking problem with a high AUDIT level has a significant relevance with an abnormal increase of indices for obesity, serum liver-enzyme levels, serum lipid levels.

• Korean Journal of Community Nutrition
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• v.22 no.5
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• pp.441-455
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• 2017

Objectives: The purpose of this study is to describe beverage patterns among healthy Korean adults and investigate their association with prevalence and components of metabolic syndrome. Methods: Subjects consisted of 6,927 Korean adults, aged 19-64 years in the $6^{th}$ Korea National Health and Nutrition Examination Survey (KNHANES, 2013-2015). Beverages were regrouped into twelve groups based on food codes and beverage intake (g/day) was assessed by 24-hour recall. Factor analysis was used to obtain beverage patterns. Waist circumference and body mass index (BMI) were used as anthropometric data; fasting blood glucose, triglyceride, high density lipoprotein (HDL), and blood pressure were used as biochemical indicators. The odds ratio (OR) for prevalence of metabolic syndrome and components of metabolic syndrome was assessed using logistic regression analysis. Results: Three beverage patterns were identified using factor analysis: 1) carbonated soft drinks 2) coffee (without added sugar or powdered creamer), and 3) alcoholic beverages. Subjects with high scores for the carbonated soft drink and coffee without added sugar or powdered creamer patterns were younger and subjects with high scores for the alcoholic beverage pattern were older. There were significant differences in gender distribution in all three beverage patterns, with men more likely to have high scores for carbonated soft drink and alcoholic beverage patterns. On the other hand, women were more likely to have higher scores for coffee without added sugar or powdered creamer pattern. Within each pattern, there were significant differences in sociodemographic and lifestyle characteristics such as education, household income, frequency of eating out, and smoking status according to the quartile of pattern scores. Alcoholic beverages and carbonated soft drinks patterns were associated with an increased levels of metabolic syndrome components, but coffee without added sugar or powdered creamer was not associated with any of metabolic syndrome components in healthy Korean adults after adjusting for age, sex, education, BMI, weight management, household income, smoking status, frequency of eating out, and energy intake. Conclusions: Alcoholic beverages and carbonated soft drinks patterns are associated with increased levels of metabolic syndrome components while coffee without added sugar or powdered creamer pattern is not associated with any of metabolic syndrome components in healthy Korean adults.

• Journal of Distribution Science
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• v.10 no.4
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• pp.37-45
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• 2012

The popularity of courier services in Korea has made it an essential part of the country's domestic logistics industry, bolstering the growth not only of the national economy, but also the quality of people's daily lives. An effective strategy for courier companies in Korea would be to provide high-quality services to their existing target markets with the goal of maximizing customer loyalty. This study investigates structural relationships between customer loyalty and service quality as a set of factors and between customer trust and customer satisfaction. These antecedent relationships will be used to understand the "performance formation model" through service quality. In this study, service quality, as a set of factors, is considered to be the independent variable, while customer satisfaction and customer trust are both treated as intervening variables. Finally, customer loyalty is the dependent variable. Following a review of the literature, this paper's proffered hypothesis will be investigated in terms of whether the independent and intervening variables significantly affect customer loyalty. A statistical analysis of the empirical research was carried out using both SPSS 18.0 and AMOS 18.0 The results of this study's empirical analysis show three conclusions. First, among the intervening variables (customer satisfaction and customer trust), customer satisfaction is significantly correlated with customer loyalty. Customer trust, however, was shown to have little or no relationship to customer loyalty. Second, the quality of service variable seems to influence customer satisfaction, customer trust, and customer loyalty. Third, with respect to the relationship of intervening variables, customer trust affects customer satisfaction. Thus, the companies that have a competitive advantage in Korea have successfully maximized customer loyalty for their existing customers. Courier companies will need to research and study customer needs. Therefore, this research suggests that effective courier service management can be better understood through the application of the service quality performance formation model, which can enhance the quality of service provided by domestic courier services. This research is limited to investigating qualitative variables, such as the service quality factors, customer satisfaction, and customer trust. It would be helpful for future research on courier services to consider quantitative variables, such as price and weight.

• Journal of the Korean Data and Information Science Society
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• v.27 no.3
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• pp.791-801
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• 2016

The purpose of this study is to examine factors affecting the intent of re-employment of inactive registered nurses. This study presents a secondary analysis of data collected in 'Nurse Turnover On-line Survey' by Korean Nurses Association and Korea Institute for Health and Social Affairs in 2014. The analysis shows that 70.9% of inactive RNs has an intent to return to practice, and most of them preferred 'flexible working options' (47.8%) or 'fixed day shifts' (43.3%) as a work pattern. Main reasons for resigning from their last job have been found to be 'high work intensity' (18.8%) and 'difficulties of night shifts' (16.7%). Inactive married RNs who have working histories in a general hospital or a long-term care hospital or have preferences for traditional shift works showed a stronger intent to return to practice than their reference group. Our study shows that, for inactive RNs to return to practice, it is recommendable to adopt various non-traditional working patterns, to make a staffing distribution considering the labor intensity and to develop education programs designed to increase RNs' professional satisfaction.

• The Korean Journal of Financial Management
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• v.26 no.3
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• pp.103-138
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• 2009

In this article we examine a unique data set of intraday fair disclosure(FD) releases to shed light on market efficiency within the trading day. Specifically, this paper analyze the response of stock prices on fair disclosure disseminated in real-time through KIND(Korea Investor's Network for Disclosure) on Korea stock exchange during the period from January 2003 to September 2004. We find that the prices of stock experiences a statistically and economically significant increase beginning seconds after the fair disclosure is initially announced and lasting approximately two minutes. The stock price responds more strongly to fair disclosure on smaller firm but the response to fair disclosure on the largest firm stock is more gradual, lasting five minutes. We also examine the profitability of a short-term trading strategy based on dissemination of fair disclosure. After controlling for trading costs we find that trader who execute a trade following initial disclosure generate negative profits, but trader buying stock before initial disclosure realize statistically significant positive profit after two minute of disclosure. Summarizing overall results, our evidence supports that security prices on Korea stock exchange reflects all available information within two minutes and the Korea stock market is semi-strongly efficient enough that a trader cannot generate profits based on widely disseminated news unless he acts almost immediately.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.49-55
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• 2016

Background: For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of $^{137}Cs$ and $^{90}Sr$ in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. Materials and Methods: For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using ${\gamma}$-ray spectrometry with HPGe detector, the concentrations of $^{137}Cs$ were determined and the concentrations of $^{90}Sr$ were measured by counting ${\beta}$-activity of $^{90}Y$ (in equilibrium with $^{90}Sr$) in a gas flow proportional counter. Results and Discussion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ were $<0.479-39.6Bq{\cdot}(kg-dry)^{-1}$ (avg. $7.51Bq{\cdot}(kg-dry)^{-1}$) and $0.209-1.85Bq{\cdot}(kg-dry)^{-1}$ (avg. $0.74Bq{\cdot}(kg-dry)^{-1}$) which were similar to the reported values from other regions in Korea. The activity ratio of $^{137}Cs$ to $^{90}Sr$ in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of $^{90}Sr$ after fallout than that of $^{137}Cs$. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The $^{137}Cs$ concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while $^{90}Sr$ showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the $^{137}Cs$ and $^{90}Sr$ concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between $^{137}Cs$ and TOC (determination coefficient $R^2=0.6$). Conclusion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties was between $^{137}Cs$ and TOC.

• Korean Security Journal
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• no.49
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• pp.157-183
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• 2016

Countries across the globe, including those in Europe, are waging a "war against terrorism" as international terrorist groups such as ISIS and lone-wolf terrorists have unleashed various large-scale attacks on rail infrastructure. Anti-South Korean sentiment exists in Muslim-majority countries because the nation has cooperated with the US for its military interventions in the Middle East, and ISIS has threatened to target South Korea four times since September 9, 2015. In addition, North Korea has been left isolated in the international community with its missile and nuclear tests, while further escalating inter-Korean tension and threatening to strike major facilities and attack important figures in the South. These situations imply that South Korea is no longer immune to terrorist attacks. If the nation fails to prevent or deter such terrorist attacks against rail networks, massive casualties, property damage and social confusion would be unavoidable, deteriorating national and international trust in its counter-terrorism policies. This may lead to a national crisis involving decreases in the number of tourists, dampened interest of foreign investors, and capital flight. This study aims to propose policy measures to enhance railroad security checks, based on the work of railroad police officers, for the sake of protecting citizens and public safety. The suggestions include an incremental expansion of railroad security checks; growth of the railroad police force and adjustment of their policing distribution with other police officers; enhancement of security systems across important rail networks; improvement of the Railroad Safety Act; Southeast Asia, including the corresponding strengthening of the national crackdown illegal immigrants, and plans for pre-emptive and regular cooperation among organizations related to the promotion of security checks and the prevention of terrorist attacks.

• Korean Security Journal
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• no.31
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• pp.125-155
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• 2012

Terrorist organization has shown the trend of secret organization and it is harder to cope with terrorism because of uncertainty of terrorism. Homegrown terrorism is the one, whose preparation, execution and effect are restricted to domestic area. By the way, in the worldwide economic depression, violence and radical demonstration have shown the expansion trends as in Middle East, political revolution of Africa, anti-social resistance of Europe and Wall Street Occupation of USA. Homegrown terrorism is occurring in various countries such as UK and Spain as well as USA. Specialists warn homegrown terrorism in Korea. The purpose of this study was to prospect the possibility of homegrown terrorism that can be generated in the transfer to multi-culture society as various foreigners come to Korea rapidly and suggest the method to cope with the trend. The study analyzed environment and analysis of homegrown terrorism that Korea faces now. The methods to cope with homegrown terrorism are as follows. First, distribution of radical homegrown terrorism via internet should be prevented. Second, the connection between terrorist organization and homegrown terrorist should be prevented. Third, there should be a cooperation among government, residents and religious group. Fourth, there should be an open approach against multi-culture society. Fifth, there should be a systematic control for cause of new conflict. Finally, there should be a long-term approach to cause of new conflict. If we do not make an effort to prevent homegrown terrorism, terrorism environment may face new aspect and national and social cost for it will increase.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.819-829
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• 2020

This empirical research is aimed at testing the relationship of the big five personality traits namely openness to experience, extraversion, consciousness, agreeableness, neuroticism, and risk aversion with the investment intention of individual investors belonging to Balochistan, Pakistan. The primary data is collected through a self-administered questionnaire (a structured form that consists of a series of closed-ended and open-ended questions) from a sample of 397 active individual investors belonging to different districts of the province. The data is empirically analyzed by applying the Partial Least Square (PLS) path modeling technique by using the estimation package available in Smart-PLS. The findings of this study suggest that all the variables are statistically significant with investors' investment intention with risk aversion as the strongest predictor. Moreover, openness to experience, extraversion, consciousness, agreeableness, and risk are significantly and positively related to an investor's investment intention, whereas neuroticism is negatively related to an investor's investment intention. The results extended by this study can be used by financial planners and investment bankers to channelize the available financial resources in diversified portfolios. The results will help financial planners to make available diverse investment alternatives for investors in Balochistan, thus catering to their unique needs. Academia must offer courses on contemporary finance paradigm based on behavioral finance to enable future business graduates to make wise financial decisions.