• Journal of the Korean Data and Information Science Society
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• v.28 no.6
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• pp.1511-1520
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• 2017

The purpose of this study is to analyze military combat training data to improve military operation and training methods and verify required military doctrine. We set the number of combat disabled enemies, which the individual combatants make using their weapons, as the response variable regarding offensive operations from scientific military training data of reinforced infantry battalion. Our response variable has more zero observations than would be allowed for by the traditional GLM such as Poisson regression. We used the zero-inflated regression and the hurdle regression for data analysis considering the over-dispersion and excessive zero observation problems. Our result can be utilized as an appropriate reference in order to verify a military doctrine for small units and analysis of various operational and tactical factors.

• Asian Journal of Business Environment
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• v.13 no.4
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• pp.19-28
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• 2023

Purpose: Emerging markets under industrialization have become increasingly influential over the global natural-resource transactions. However, their average deal completion rates have been relatively low. The international business (IB) literature regards the low rate as evidence of 'double hurdle', the extra disadvantages in doing overseas business for firms from developing countries. Because legitimacy building mitigates liability of foreignness, we argue that an acquirer's environmental responsibility effectively builds legitimacy. Research design, data and methodology: Stakeholders in the host country spread the acquirer's environmental responsibility so that, by raising legitimacy, they may strengthen the link between environmental responsibility and deal completion. Our dataset consists of the 608 cross-border acquisition deals announced by the 196 firms in Brazil, Russia, India, and China over 2008-2019 period. Results: A logit regression result confirms that environmental responsibility increases the likelihood of acquisition deal completion. Also, host-market stakeholders positively moderate the relationship between environmental responsibility and the likelihood of deal completion. Conclusions: Overall, this study contributes to the IB literature by identifying environmental responsibility as a key approach to lowering the double hurdle in internationalization of firms in emerging markets. Any emerging multinationals interested in the foreign, brownfield entries to the natural-resource industries must enhance the environmental responsibility, which turns out extremely important.

• Journal of Industrial Convergence
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• v.22 no.8
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• pp.1-17
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• 2024

Recently, interest in edutech has been focused on its fusion with AI technology, and the market in this field is expanding. This study aims to analyze the technological competitiveness and key technological areas of major countries in the AI-edutech field. Additionally, considering that AI-edutech is a convergence of AI technology and edutech, the study seeks to examine the path dependence of AI-edutech in each country to determine whether they are based on existing AI technologies or edutech. To this end, AI-edutech patents were collected and competitiveness was analyzed using patent activity, patent impact, and market acquisition indicators. Path dependence for each country was analyzed using the hurdle negative binomial regression model. The analysis results indicate that the major countries in the AI-edutech field are China, South Korea, the United States, India, and Japan. In terms of patent activity, China had the highest level, followed by South Korea. In terms of patent impact and market securing power, the United States was high in both aspects, Japan had high market securing power, and South Korea had high patent influence. The results of the hurdle negative binomial analysis presented unique findings. The logit part results indicated that the possession of existing AI and edutech did not positively affect the emergence of current AI-edutech, but the count part results showed a positive influence. This suggests that, overall, it is difficult to assert that current AI-edutechs are based on past AI and edutechs. However, once some AI-edutechs based on existing AI and edutechs emerge, they are influenced by the existing technologies. These findings provide implications for future research and technological strategies in this field.

• Genomics & Informatics
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• v.14 no.4
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• pp.138-148
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• 2016

The success of genome-wide association studies (GWASs) has enabled us to improve risk assessment and provide novel genetic variants for diagnosis, prevention, and treatment. However, most variants discovered by GWASs have been reported to have very small effect sizes on complex human diseases, which has been a big hurdle in building risk prediction models. Recently, many statistical approaches based on penalized regression have been developed to solve the "large p and small n" problem. In this report, we evaluated the performance of several statistical methods for predicting a binary trait: stepwise logistic regression (SLR), least absolute shrinkage and selection operator (LASSO), and Elastic-Net (EN). We first built a prediction model by combining variable selection and prediction methods for type 2 diabetes using Affymetrix Genome-Wide Human SNP Array 5.0 from the Korean Association Resource project. We assessed the risk prediction performance using area under the receiver operating characteristic curve (AUC) for the internal and external validation datasets. In the internal validation, SLR-LASSO and SLR-EN tended to yield more accurate predictions than other combinations. During the external validation, the SLR-SLR and SLR-EN combinations achieved the highest AUC of 0.726. We propose these combinations as a potentially powerful risk prediction model for type 2 diabetes.

• Korea journal of population studies
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• v.30 no.3
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• pp.107-135
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• 2007

This paper uses a static Gamma count model, a traditional hurdle model and an endogenous switching Poisson model, respectively for determining married women's completed fertility rates in Korea. This paper analyzes the impact of household income, women's wage and education, and women's job market participation on the number of children of married women above age 40 and on the expected number of children of women aged below 40. The paper shows that a household income significantly increases the number of children for at least women aged above 40, however, this income effect is disappearing for younger generation. The empirical model suggests that women having a job tend to have fewer children for a group 39 years old and below and find that there is an endogeneity problem between child birth and labor force participation, too. The education level of married women gives a positive effect for giving a birth, itself, while it gives a negative impact on the number of children. Based on the empirical results, it concludes that Becker's Quantity-Quality theory works for Korea, too.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.131-143
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• 2012

The past researches on roadway segment safety estimation focused on intersections, which are the primary traffic accident regions. The past researches on roadway segments, However, analyzed the effects of certain factors on the traffic accident occurrence rate by organizing the individual geometric structures of the roads, and there is still a dearth of researches on the development of a traffic accident estimation model for rural roadway segments. Therefore, this research focused on rural two-lane and multilane roadway segments and developed traffic accident estimation models through the application of statistical techniques. This is required to explain such high frequency of zero counts in the traffic accident data. In this research, it was found that the Hurdle model is more suitable than the Poisson or negative binomial-regression model for explaining the excess zeros case. In addition, main variables were chosen to estimate their effects on traffic accident occurrence at rural roadway segments, and the safety at such rural roadway segments was estimated. In this research, it was assumed that there are different factors that affect the safety at two-way lane and multilane roadway segments, and a traffic accident estimation model was developed by dividing the two-way lane and multilane roadway segments.

• Journal of Korea Technology Innovation Society
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• v.21 no.4
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• pp.1508-1535
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• 2018

Employment in enterprises is a consecutive decision-making process based on the results of their innovative activities and it is necessary to consider this relationship as well explicitly in an analysis of the employment performance through technological innovation. Based on this critical mind, this study would analyze the structural relationships among enterprises' innovative activities, the performance of technological innovation, a compensation system and the creation of employment, reflecting the correlation of the process of the actual technology management performed simultaneously, utilizing the seemingly unrelated regression(SUR) model to estimate a simultaneous equation in addition to analyzing the relationship between technological innovation and the effect on employment with the ordered logit model to estimate a single equation as in the preceding studies. As a result of the analysis, a structural relationship could be found out, in which the execution of the compensation system would increase the performances of technical development and technology commercialization, which in turn, accelerates enterprises' employment. Especially, it is judged that enterprises' employment performance increases when technological innovation is managed from a process perspective in that the commercialization performance, as well as technical development, acts as a kind of hurdle in the effect on employment.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.285-292
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• 2018

The purpose of this study is to analyze the association of smoking cessation attempts and the perceived stress level and to identify the factors affecting the perceived stress level of quit smoking. The study utilized the 2015 Korean National Health and Nutrition Examination Survey, and was applied an Ordinal Logistic Regression to examine the association of smoking cessation attempts and perceived stress level. The current smoker those who experience failure in smoking cessation, were more stressful than those who experience success in smoking cessation (OR=1.72, CI;1.41-2.08). This study identified smoking cessation failure as a major psychiatric factor associated with high perceived stress level, and suggests high stress after smoking cessation failure as one of the reasons why smokers do not reach complete smoking cessation. Also, in order to promote smoking cessation, it is needed to have political approach in reducing the psychiatric hurdle like high stress after smoking cessation failure.