• The Korean Journal of Applied Statistics
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• v.35 no.1
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• pp.49-62
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• 2022

Realized volatility is well known to have long memory, strong association with other global financial markets and interdependences among macroeconomic indices such as exchange rate, oil price and interest rates. This paper proposes autoencoder factor-augmented heterogeneous autoregressive (AE-FAHAR) model for realized volatility forecasting. AE-FAHAR incorporates long memory using HAR structure, and exogenous variables into few factors summarized by autoencoder. Autoencoder requires intensive calculation due to its nonlinear structure, however, it is more suitable to summarize complex, possibly nonstationary high-dimensional time series. Our AE-FAHAR model is shown to have smaller out-of-sample forecasting error in empirical analysis. We also discuss pre-training, ensemble in autoencoder to reduce computational cost and estimation errors.

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.217-225
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• 2022

We analyzed efficiency and productivity of the Indian non-life insurance market affected by the COVID-19 pandemic from 2020. Using data envelopment analysis(DEA), we examined non-life insurance companies selling health insurance products in India from FY2013 to FY2019. We found the followings. First, average efficiency of the entire non-life insurance industry worsened in the beginning yet improved later. Second, analyzing the efficiency measures by group, we found that private insurance companies had the highest efficiency, followed by state-run insurance companies and pure health insurance companies. Third, average annual productivity growth rate of companies operating distance selling channels including telemarketing is higher than that of traditional face-to-face channels. During and after the COVID-19 pandemic, therefore, Indian non-life insurance companies should focus their resources and efforts on the development of distance selling channels when establishing business strategies. Besides, it would be interesting to extend our analysis to the post-coronavirus period and we leave this for future research.

• Journal of Korea Port Economic Association
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• v.38 no.2
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• pp.49-67
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• 2022

This study applied the method of Diebold and Yilmaz (2012, 2014, 2016) to analyze the connectedness between the Freight Index (BDI, BDTI, BCTI), energy price(oil, natural gas, coal), and grain price(soybean, corn, wheat) from July 19, 2007 to March 31, 2022. The main analysis results of this paper are as follows. First, according to the network analysis results, the total connectedness was measured to be 20.43% for the entire analysis period, indicating that there was a low correlation between the freight index and the commodity price. In addition, looking at the directional results, the variable with the greatest effects was corn, and conversely, the variable with the lowest effects BDI. When classified by events, BCTI was found to play a major role only during the COVID-19 period. Second, according to the results of the rolling-sample analysis, the total connectedness be found to be highly correlated with changes in economic conditions such as the financial crisis, trade war, and COVID-19 when specific events occurred.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.585-592
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• 2022

The purpose of this paper is to examine the relation between executive excesss compensation and credit rating. According to the prior research which show the negative effects of excess compensation on a firm's future performance, this paper expects the negative effect of excess compensation on credit rating. Using a sample of Korean listed non-financial firms from 2014 to 2019, I perform the multivariate regressions analysis of excess compensation on credit rating. I find that excess compensation is negatively related to credit rating when executive compensation exceed expected executive compensation. Moreover, I find that the result is constant when a fim belongs to small-medium business. These results show that credit rating is affected by executive excess compensation and the relation could be different by the type of firm's size. Therefore, this study contributes to the literature by suggesting the possibility that capital market is aware of negative effect of executive excess compensation.

• Journal of Industrial Convergence
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• v.21 no.4
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• pp.1-12
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• 2023

The era of digital transformation is rapidly emerging in industries and academia, including finance and logistics, and the consulting market for digital transformation is also growing. According to previous studies, the need for digital transformation is also mentioned in consulting institutions. In this process, the role of consultants should be changed according to the times, and customer relationship management and attitude toward customers are emphasized. However, consulting research has the point that research on this has not been studied in depth. Therefore, the purpose of this study is to develop an element of attitude focusing on consultant attitudes in the field of digital transformation. As a result of research using literature analysis and modified Delphi techniques, 'customer orientation', achievement orientation', professional dignity', 'maintenance of expertise', and 'ethics' were found to be key attitude factors. This study is meaningful in that consultant attitude elements in the digital transformation field were explored and developed by verifying content validity, and consultants in the digital transformation field can recognize the importance of attitude and use it as a basic tool for capacity improvement.

• Journal of Korea Port Economic Association
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• v.39 no.1
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• pp.17-34
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• 2023

The maritime industry is undergoing significant changes due to digitalization and decarbonization, collectively known as "2D." This study investigates how these transformations are impacting the industry's business models. Since the changes are still ongoing, a cognitive approach was used to derive business models, rather than relying on actual case studies. The study presents experimental maritime business models that correspond to the four types of business model frameworks (or archetypes), along with recent trends for each model. The research results show that new business models are emerging in various areas, including the commercial and technical fields of the maritime industry. This thought-provoking study is significant as a pioneering investigation that will stimulate subsequent case-based research in academia and provide strategic guidance to market participants or policy makers in the maritime industry.

• Journal of Internet Computing and Services
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• v.24 no.2
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• pp.67-74
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• 2023

Stock price prediction research in the financial sector aims to ensure trading stability and achieve profit realization. Conventional statistical prediction techniques are not reliable for actual trading decisions due to low prediction accuracy compared to randomly predicted results. Artificial intelligence models improve accuracy by learning data characteristics and fluctuation patterns to make predictions. However, predicting stock prices using long-term time series data remains a challenging problem. This paper proposes a stable and reliable stock price prediction method using K-means clustering-based data augmentation and normalization techniques and LSTM models specialized in time series learning. This enables obtaining more accurate and reliable prediction results and pursuing high profits, as well as contributing to market stability.

• Korea Trade Review
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• v.42 no.2
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• pp.227-249
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• 2017

This study investigates whether foreign equity ownership is associated with trading volume. This study establishes null hypothesis indicating that foreign equity ownership is not related to trading volume based on prior studies regarding foreign equity ownership. We measured trading volume as proxy of investors' heterogeneous beliefs. To exam The the hypothesis, we collected sample firms listed on the Korean Stock Exchange from the year of 2001 to the year of 2011 inclusively. Controlling for variables related with trading volume as reported in the previous studies, the regression coefficient for the foreign equity ownership showed statistically significant negative sign. These results indicate that the foreign equity ownership is negatively associated with investors' heterogeneous beliefs. This study contributes to extant literature on foreign equity ownership by providing evidence that foreign equity ownership affects investors' trading decisions. The results also help policy makers in their policy development.

• Korea Trade Review
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• v.42 no.4
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• pp.49-68
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• 2017

This paper investigates the spillover effect of the U.S. Interest on Korea's interest rate as well as the role of exchange rate in the spillover effects, by utilizing a open macro model on the determinants of long-term interest rates. According to the cointegration estimation and the Impulse response function, it is found that, across both long-term and short-term, there exist the spillover effect of the U.S. Interest on Korea's interest rate. The fiscal deficit and expected exchange rate have significantly positive relationship with the Koreas's long-term interest rate. Further, foreign exchange market intervention in Korea did not have significant effect on the spillover effect. Thus, this study suggests that exchange rate flexibility would not be enough to restrain the spillover effects of the U.S. interest rate.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.72-72
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• 2020

전 세계 태양광 발전용량은 2010년 초 25GW에서 2019년 말 617.9GW로, 지난 10년 동안 25배 이상 증가하였다(2019년 전세계 태양광 발전(PV)의 추가량은 거의 133GW 추정). 2020년에도 세계 태양광시장은 120~150GW를 형성해 전년대비 10% 내외의 성장세를 이어갈 것으로 전망되며, 향후에도 성장률은 다소 낮아지겠지만 2030년 태양광 수요피크 200GW까지 지속적인 성장이 기대된다. 한편 우리나라 수상태양광은 높은 잠재력(저수면적의 7%를 활용할 경우 5,304MW 규모의 수상태양광 개발이 가능)을 가지고 있는 것으로 평가된다. 신(新)정부 국정과제 3020 신재생 확산정책에 따라 신재생에너지 보급률 확산이 전망되는 가운데, K-water의 중장기('17~'26) 전략경영계획에 따르면 수상태양광은 2026년까지 2,758MW 개발을 목표로 하고 있다. 하지만, 수상태양광은 경제성과 환경적 측면에서의 불확실성을 포함하여 시설물의 안정성 검증, 사회적 수용성 등 극복해야 할 정책과제들을 안고 있다. ① REC 가격의 안정화, 경제성 제고 문제(높은 운영 및 관리 비용), ② 난개발, 환경·경관·안전 문제에 대한 주민들의 우려 : 주민 수용성 제고, ③ 투자 사기와 유착·비리, 편법개발, 난개발에 대한 규제방안, ④ 지역사회와의 거버넌스 및 갈등관리 문제, 공용 전력망 부족과 계통연계 문제 등. 이에 본 연구는 태양광 선도국가의 정책 사례 분석을 통해 수상태양광 관련 명확한 규제 및 지원정책을 제언하고자 한다. 분석방법으로는 첫째, 주요 국가에서 시행 중인 수상태양광에 대한 금융지원 및 정책 지원을 국내 사례와 비교·분석하였으며 둘째, 경제적·생태적 관점에서 수상태양광 모델을 개발하고, 이를 지역사회가 수용할 수 있도록 정책적 대안을 제시하였다.