A Study on the Development of Fuzzy Linear Regression I

Kim, Hakyun Korea Association of Information Systems 1995 情報시스템硏究 Vol.4 No.-

This study tests the fuzzy linear regression model to see if there is a performance difference between it and the classical linear regression model. These results show that FLR was better as f forecasting technique when compared with CLR. Another important find in the test of the two different regression methods is that they generate two different predicted P/E ratios from expected value test, variance test and error test of two different regressions, though we can not see a significant difference between two regression models doing test in error measurements (GMRAE, MAPE, MSE, MAD). So, in this financial setting we can conclude that FLR is not superior to CLR, comparing and testing between the t재 different regression models. However, FLR is better than CLR in the error measurements.

The Impacts of Verbal Violence of SNS on Educational Performance

KIM HaKyun 동북아시아문화학회 2018 동북아시아문화학회 국제학술대회 발표자료집 Vol.2018 No.07

퍼지의사결정 도구로서 퍼지회귀분석방법과 회귀분석방법의 비교연구

김하균(Kim, Hakyun) 대한경영학회 1996 大韓經營學會誌 Vol.13 No.-

금융상품추천 전문가시스템을 이용한 은행의 eCRM 설계 및 구축 방안에 관한 연구

김하균(Kim HaKyun),정석찬(Jeong Seok-Chan) 한국전자거래학회 2004 한국전자거래학회지 Vol.9 No.3

은행 등과 같이 고객의 서비스를 중요시하는 산업에서는 고객 만족도 향상을 위하여 eCRM (e-Customer Relationship Management)의 개념 도입이 촉진되고 있다. 이러한 고객의 만족도 향상을 위한 방안으로 본 연구에서는 은행의 금융상품 추천업무를 대상으로 전문가시스템을 이용한 eCRM 구축에 대하여 검토를 실시하였다. 이를 위하여 먼저 전문가시스템을 활용한 eCRM 시스템의 아키텍처를 제시하였고, 고객에게 금융상품 추천을 위한 전문가시스템 프로토타입을 개발하였다. 본 연구에서 제시된 금융상품추천 전문가시스템을 활용한 e-CRM시스템은 고객에게는 보다 양질의 금융 서비스를 제공하게 되며, 은행에서는 고객에 대한 보다 정확한 정보 수집이 용이하게 된다. In banking industry, as competition of retail finance is intensive, there appeared eCRM which is a kind of marketing strategy, not only screening good customers but also doing one-to-one marketing for improving customer royalty and satisfaction of goods and service of bank. The strategic importance of eCRM is increasing more and more. We studied bank to use the advantage of expert system and eCRM. The expert system is used as a tool to analyze eCRM. In this paper, first, we presented an eCRM system architecture using expert systems in banking business. Secondly, a bank financial goods recommendation system using expert system is designed and developed. Customers will receive the good quality financial services from the expert system and banks also will acquire the good quality customer data from the expert system.

The Effect of Convenience Store Diversification on Repurchase Intention

Hongkuk Kim,Hakyun Kim(金河均) 동북아시아문화학회 2017 동북아시아문화학회 국제학술대회 발표자료집 Vol.2017 No.7

It is not an exaggeration to say that it is convenience store if it is present small store. Recently, convenience stores are transforming into living culture space by carrying out various task such as courier service, photo printing, postal service, etc., as well as banking through ATM devices in the concept of selling merchandise. The reason for this is that the trend of modern consumers has priority over convenience and accessibility. As competition among convenience store companies becomes more intense, convenience stores are trying to improve the quality of service and convenience of customers by adding various services in addition to the existing strategy of operating 24 hours. Therefore, we are strategically improving sales accordingly. The purpose of this study is to investigate the relationship between customer satisfaction and positive emotions, and the intention of repurchase. As a result of this study, it is expected that the theoretical and practical contribution will be made to the direction of service quality and convenience research along with the research related to diversification of distribution industry such as convenience store in the future. This study will test the following hypothesis by constructing a model in theoretical studies with empirical studies. First, convenience store diversification will have a positive effect on convenience. Second, convenience store diversification will have a positive effect on customer satisfaction. Third, the convenience of convenience stores will have a positive effect on customer satisfaction. Fourth, the convenience of convenience stores will have a positive effect on customers’ repurchase intention. Fifth, customer satisfaction will have a positive effect on customers’ repurchase intention.

전산세무회계 교육용 소프트웨어의 시스템특성 및 개인적 특성이 교육만족도를 매개로 교육성과에 미치는 영향

김현규(Hyeongyu KIM),소원현(Wonhyun SO),김하균(Hakyun KIM) 한국수산해양교육학회 2015 水産海洋敎育硏究 Vol.27 No.1

Volatility Spillovers across Stock Markets in Northeast Asian Countries

Wan-Min Kim(金完敏),Hakyun Kim(金河均),Jin-Soo Lee(李鎭秀) 동북아시아문화학회 2016 동북아시아문화학회 국제학술대회 발표자료집 Vol.2016 No.7

As the world becomes flatter due to increasingly integrated global financial markets, dynamic return links and volatility transmissions across the globe have drawn keen interest from individual and institutional investors. Accordingly, volatility forecasting also becomes more important than ever. In this paper, we aim to examine the characteristics of daily volatility spillovers in the stock markets across three northeast Asian countries (Korea, China and Japan), and a benchmark (USA). We collect Shanghai Stock Exchange Composite Index (SSEC), Nikkei 225 Index (Nikkei 225) from Yahoo finance, S&P 500 Index (S&P 500) from Google finance, and Korea Composite Stock Price Index (KOSPI) from Samsung Securities Co. Ltd. The daily sample covers January 5, 1993 to September 25, 2015. After harmonization of different holidays across countries, final sample size becomes 5,119. We use generalized spillover definition and measurement introduced by Diebold and Yilmaz (2012). Using 250-day rolling windows with 10-day ahead forecast errors, we find time-varying nature of daily volatility spillovers in those stock markets during important events. We hope these finding help individual and institutional investors construct improved diversified global portfolio and increase their diversification benefits.

An Analysis on Internal Exposure Evaluation Code for Radioactive Aerosols

Hakyun Lee,SunIl Kim,Jongsoon Song 한국방사성폐기물학회 2017 한국방사성폐기물학회 학술논문요약집 Vol.2017 No.10

Study on the Effect of Pressurizer Cutting Scenario

Hakyun Lee,Sunil Kim,Minho Lee,Jongsoon Song 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.1

When a permanently-closed nuclear power plant is to be decommissioned, large structures targeted to be cut in the process include a steam generator, reactor, and reactor coolant pump (RCP). Although there are sufficient preliminary studies being done on these structures to assess the radiation exposure dose, relatively fewer studies are underway regarding pressurizers. Therefore, preliminary evaluations are required to prevent workers from being overexposed to radiation coming from a pressurizer and to avoid an unnecessary increase in the decommissioning cost. This study created a cutting scenario based on disposal drums for solid radioactive wastes. The cutting scenario was based on 200-liter and 320-liter drums for solid wastes and on the assumption that all cutting operations were done 100 centimeters away from the structure to be cut. When are cutting process of a Pressurizer is carried out per scenario, the 200-liter drum produces 272 pieces, whereas the 320-liter counterpart generates 234 pieces. Given that South Korea allocates 75,550 KRW per liter (based on 200 L) for the disposal cost, an increase in the number of drums leads to an exponential growth of the decommissioning cost, which fuels the need to establish more organized cutting strategies. Meanwhile, in terms of radiation dose, plasma, laser, and flame cutting techniques were estimated to record 0.232 mSv, 0.299 mSv, and 0.213 mSv respectively for 200 L, and 0.195 mSv, 0.251 mSv, and 0.179 mSv respectively for 320 L (based on DF-90). When compared with the annual dose limit of 100 mSv (0.0057 mSv·hr?1), the above numbers registered for both 200 L and 320 L were estimated to satisfy the dose limit, with only a negligible difference in the dose between the two capacities. The results generated from this study are expected to be utilized as a meaningful basis to identify applicable cutting techniques of a pressurizer as part of the decommissioning operation and to establish its cutting plans in compliance with ALARA.

Plastic recycling and material flow of packaging expanded polystyrene by EPR in South Korea

( Hakyun Song ),( Youngsun Kwon ),( Yong-chul Jang ),( Byeonghwan Kim ),( Dong Gyu Shin ),( Yongseon Lee ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-

Expanded polystyrene (EPS) is one of the thermoplastic polymers that are widely used in many industrial applications such as insulation, packaging, aquaculture floats, and buoys. Since it has the property of easy material decomposition into small microplastics under natural environment, stringent management measures for such materials are urgently required. In this study, material flow analysis (MFA) was conducted to determine quantitative flows of the materials by life cycle (manufacturing, use, collection, recycling and disposal). Based on the results, the predicted EPS consumption by 2030 was estimated using several linear regression methods. In 2019, approximately 47,000 tons of packaging EPS out of total 337,000 ton EPS were consumed and distributed in Korea. About 53,000 tons of waste EPS forms were collected by recycling waste streams, out of which 41,900 tons were recycled as ingot (40,871 tons), fire-resistance coatings for steel frames (1,521 tons), and pellet (287 tons). By using the regression analysis, from 2003 to 2019, the amount of EPS consumption was steadily increased, and the cumulative amount of EPS recycling by the period was estimated to be about 412,000 tons by 2030. This study evaluated the potential benefits of resource savings and reduction of greenhouse gas emissions through EPS packaging recycling.