• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.153-159
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• 2021

The purpose of this study is to determine the demage of tooth surface changes according to exposure time of commercially available green grape juice and pomegranate juice. Extracted healthy human premolar enamel surfaces were used. Control group immersed in phosphate-buffered saline (PBS) and 10 ml of commercially available green grape juice and pomegranate juice applied experimental group was divided into 7 groups. The pH of the experimental juice was measured, and the change and micrographics of the surface were confirmed through a Scanning Electron Microscope (SEM). It was found that the more the immersion time between the tooth surface and acid juice, such as damage to the tooth surface, has a greater effect on the surface damage. Based on the results of this study, it is necessary to reduce the number of drinking times and retention time in the oral cavity.

• Journal of the Society of Disaster Information
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• v.17 no.3
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• pp.543-555
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• 2021

Purpose: The purpose of this study is to analyze the walking characteristics of jaywalking pedestrians, which account for a large proportion of deaths in pedestrian traffic accidents. Method: As for the analysis method, after collecting data of jaywalking pedestrians using imaging equipment, frequency analysis and statistical verification were performed on the jaywalking characteristics of elderly and non-elderly people. Result: It was found that there was a difference in the characteristics of jaywalking between the elderly and non-elders, but in the case of walking speed, insignificant results were derived. However, it was found that among the elderly, the group having difficulty walking in general had a lower walking speed than the group that did not. Conclusion: It is judged that one of the causes of jaywalking is the perception of illegal activities and insensitivity to the risk of accidents, not the age and walking ability. Therefore, in addition to safety education, it is judged that it is necessary to provide pedestrian safety information that requires the driver's attention in multiple jaywalking sections.

• Journal of the Korean Data and Information Science Society
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• v.27 no.5
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• pp.1293-1305
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• 2016

In this paper, we develop debt collection predictive models for the person in arrears by utilizing the direct loan data of the Korea Student Aid Foundation. We suggest credit risk scorecards for overdue student direct loan using the developed 3 models. Model 1 is designed for 1 month overdue, Model 2 is designed for 2 months overdue, and Model 3 is designed for overdue over 2 months. Model 1 shows that the major influencing factors for the delinquency are overdue account, due data for payment, balance, household income. Model 2 shows that the major influencing factors for delinquency loan are days in arrears, balance, due date for payment, arrears. Model 3 shows that the major influencing factors for delinquency are the number of overdue in recent 3 months, due data for payment, overdue account, arrears. The debt collection predictive models and credit risk scorecards in this study will be the basis for segmented management service and the call & collection strategies for preventing delinquency.

• Journal of Gifted/Talented Education
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• v.20 no.3
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• pp.1005-1026
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• 2010

Here we live in a fast changing world. The information and communication technologies have been surprisingly developing and making progress of our society. One of the benefit about the information and communication technologies is an internet. We can't imagine our life without it and it finally ends up with causing internet addiction which is called side effect of it. Most of former studies were, however, about game addiction and psychological factors of indivisual. In fact, there was not enough studies about internet addiction of computer science gifted students. If we analize the difference between computer science gifted students and average students when it comes to factors of internet addiction, we would surely be able to find out the result which is very helpful for cause analysis and its remedy. This paper examined the risk and protection factors of the former studies and choose various factors through Delphi analysis by specialists of information and science gifted students. Comparative analysis of computer science gifted students and average students was done through the test tools. And picking up unique factors of computer science gifted students, this paper shows the implication that contributes to protection of internet addiction and its remedy.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1145-1155
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• 2018

The purpose of this study was to investigate the effect of dietary restriction(DG), aerobic exercise(EG), dietary restriction with aerobic exercise(DEG) on weight, improvement of obesity, blood lipid profiles and metabolic risk factors of obese female college students. Experiments was conducted 5 times a week for 8 weeks. DG spent 300kcal/day, and EG used 300kcal/day to run, DEG each consumed 150kcal/day limits. As s result, in case of body composition, weight(p<.011) and BMI(p<.008) were decreased in DG group, and weight(p<.044, p<.017), body fat(p<.047, p<.018), BMI(p<.03, p<.008), body fat%(p<.036, p<.015) and WHR(p<.049, p<.027) were decreased in EG and DEG groups. In case of blood lipid profiles's change, there are some differences on TC(p<.006), TG(p<.047) according to the time. In DG:HDL-C(p<.028), in EG:TG(p<.038), in DEG:TC(p<.014), LDL-C(p<.007) have decreased. In case of metabolic risk factor's change, there are some differences on FBG(p<.001), insulin(p<.004), HOMA-IR(p<.001), leptin(p<.000), adiponectin(p<.038), resistin(p<.010) according to time. In DG:HOMA-IR(p<.035) and leptin(p<.007), EG:FBG(p<.043) and leptin(p<.003), DEG:FBG(p<.014), insulin(p<.005), HOMA-IR(p<.005), leptin(p<.016), and resistin(p<.040) have decreased. In conclusion, combined treatment of eating restriction with aerobic exercise was the most effective way to improvement of weight, blood lipid profiles and metabolic risk factors in obese female college students rather than respectively alone treatment.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.890-896
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• 2012

This study was conducted to evaluate soil erosion risk with a standard unit watershed in the upper Upper Nakdong River Basin according to soil characteristics and landuse using the spatial soil erosion map. The study area is $3,605.6km^2$, which consists of 2 subbasins, 35 standard unit watersheds (Andong basin 18, Imha basin 17). As a evaluation of soil erosion potential using the spatial soil erosion map, total annual soil loss and soil loss per area estimated $2,013{\times}10^3Mg\;yr^{-1}$ (Andong basin 979, Imha basin 1,034) and $6.1Mg\;ha^{-1}yr^{-1}$ (Andong basin 6.0, Imha basin 5.2), respectively. 54.2% of soil loss was originated from Arable land (Andong basin 49.0%, Imha basin 59.0%), and the area of regions, graded as higher "Moderate" for annual soil loss, was $201.7km^2$ (Andong basin 84.9, Imha basin 116.8). Average soil loss per area of unit watersheds by classification according to soil dominant parent material types ranked "Sedimentary rock group" > "Mixed group" > "Metamorphic rock group" > "Igneous rock group". In conclusion, the results of this study inform that the classification of soil parent material type would be effective for soil erosion analysis and interpretation in the Upper Nakdong River Basin.

• The Korean Journal of Applied Statistics
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• v.21 no.2
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• pp.313-325
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• 2008

Large amounts of information on individuals is available to many organizations and data users and government agencies release microdata files from their survey data or administrative records data. However, if a microdata file is released without any limitation, an invasion of privacy is likely to occur. Therefore, in creating a microdata file, agencies attempt to eliminate disclosure risk of the file while maintaining maximum utility of the data. In this paper, we introduce the concept of disclosure risk, identification and uniqueness. Also, we show the method for creating a 2% microdata file using the 2005 Korean census microdata.

• Journal of the Korean Data and Information Science Society
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• v.26 no.6
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• pp.1417-1426
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• 2015

We develop the high risk group predictive model for loan default by utilizing the direct loan data from 2012 to 2014 of the Korea Student Aid Foundation. We perform the decision tree analysis using the data mining methodology and use SAS Enterprise Miner 13.2. As a result of this model, subject types were classified into 25 types. This study shows that the major influencing factors for the loan default are household income, national grant, age, overdue record, level of schooling, field of study, monthly repayment. The high risk group predictive model in this study will be the basis for segmented management service for preventing loan default.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.164-164
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• 2017

국내 해양관련 HNS 데이터베이스의 정보를 구축하는 중에 확인된 문제점들은 크게 두 가지로 요약된다. 첫 번째는 물질정보가 없는 경우로서, 많은 경우 자연물질로 다양한 성분을 함유하고 있으며, 이외에도 이성질체 및 동족체 화합물로서 확인된다. 두 번째로는 국내 HNS DB의 출처가 다양하여, 정제되지 않은 경우인데 물질정보의 환경조건이 상이하거나 같은 조건에서도 서로 다른 정보가 혼재하는 경우이다. 이러한 문제점을 해결하기 위해, 유럽의 GESAMP에서 제시한 보고서와 미국 CAMEO를 참조하여 누락정보를 확보하였으며 두 데이터베이스의 명명법의 차이에서 오는 누락 정보를 두 데이터베이스의 유사명 자료비교와 화학구조를 이용해 확인하였다. 자연물질과 그룹화합물들도 주요성분의 자료를 활용하였으며, 이성질체의 경우 단일성분의 자료를 기입하거나, 위험성이 높은 성분의 자료를 선택해서 기입하였다. 물질정보 중 IMDG 등급의 경우 주위험성외에 부위험성의 중요성을 고려하여 HNS DB에 새로 기입하였으며, 부록으로 HS 번호 부여 및 해양환경거동분류를 첨부하였다. 향후 아직 남아있는 누락정보의 확보를 위해서는 GESAMP circular report를 확보하도록 할 필요성이 있다고 판단된다.

• Journal of the Korean Society for Computer Game
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• v.31 no.4
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• pp.145-155
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• 2018

This study aims to extract additional elements to the existing game value evaluation using Delphi technique to 23 game experts. As a result of reviewing the characteristics of the development model using the evaluation model of the existing game contents, it was found that the evaluation factor was selected when selecting the content. The Delphi analysis was conducted two times, the first was the expert FGI and the second was the Delphi questionnaire. More detailed elements were presented in the related items such as results, technology transfer and dissemination, and details for promoting commercialization. Through focus group interviews, we extracted additional factors and predicted market size, growth potential, regulatory and market appeal and risk through market analysis of content success in the game industry. This will allow the industry to understand market size, growth potential, regulation, market appeal and risk through a market analysis of its success targets. This study suggests that the proposed evaluation factors can be applied to the entire game and cultural contents industry and will also help to construct market factors such as market value evaluation of contents, goal and goal setting, selection of entry method, and strategic factors.