• Journal of the Korean Institute of Gas
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• v.7 no.3 s.20
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• pp.1-6
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• 2003

This study has suggested a decision method which determine optimum investment level for safety management by process risk assessment at gas governor station. Hazard and operability study(HAZOP), fault tree analysis(FTA) and consequence analysis(CA) were carried out and potential accident cost and benefit for safety management were estimated. As a result, we could be found the trend of safety cost and benefit by the nonlinear regression method and could be determined the optimum investment level for safety management from analysis of safety management cost and potential accident cost.

• Journal of Korean Society of Rural Planning
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• v.23 no.3
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• pp.21-36
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• 2017

Climate change is intensifying storms and floods around the world. Where nature has been destroyed by development, communities are at risk from these intensified climate patterns. This study was to suggest a methodology for estimating flood vulnerability using Potential Flood Damage(PFD) concept and classify city/county about Potential Flood Damage(PFD) using various typology techniques. To evaluate the PFD at a spatial resolutions of city/county units, the 20 representative evaluation indexing factors were carefully selected for the three categories such as damage target(FDT), damage potential(FDP) and prevention ability(FPA). The three flood vulnerability indices of FDT, FDP and FPA were applied for the 167 cities and counties in Korea for the pattern classification of potential flood damage. Potential Flood Damage(PFD) was classified by using grouping analysis, decision tree analysis, and cluster analysis, and characteristics of each type were analyzed. It is expected that the suggested PFD can be utilized as the useful flood vulnerability index for more rational and practical risk management plans against flood damage.

• ETRI Journal
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• v.37 no.3
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• pp.584-594
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• 2015

To date, many different kinds of logic styles for hardware countermeasures have been developed; for example, SABL, TDPL, and DyCML. Current mode-based logic styles are useful as they consume less power compared to voltage mode-based logic styles such as SABL and TDPL. Although we developed TPDyCML in 2012 and presented it at the WISA 2012 conference, we have further optimized it in this paper using a binary decision diagram algorithm and confirmed its properties through a practical implementation of the AES S-box. In this paper, we will explain the outcome of HSPICE simulations, which included correlation power attacks, on AES S-boxes configured using a compact NMOS tree constructed from either SABL, CMOS, TDPL, DyCML, or TPDyCML. In addition, to compare the performance of each logic style in greater detail, we will carry out a mutual information analysis (MIA). Our results confirm that our logic style has good properties as a hardware countermeasure and 15% less information leakage than those secure logic styles used in our MIA.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.1
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• pp.260-269
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• 2010

Background : Bojungikgitang(BJT) and Banhabaekchulchonmatang(BBT) are known to treat the tinnitus patients, which were registered Korean National Health Insurance coverage lists. Objective : Few studies have evaluated economic benefits of both herbal medicines. This research is to investigate the cost-effectiveness of Bojungikgitang(BJT) and Banhabaekchulchonmatang(BBT) in chronic tinnitus patients over nineteen years old. Method : We built the decision tree model of chronic tinnitus and executed the deterministic analysis and threshold sensitivity analysis based on randomized clinical trial. Effectiveness was measured in quality-adjusted life-years(QALYs), and costs were in 2009 KRW(South Korean Currency). The perspective is societal, time horizon is 10 weeks, and Korean willingness to pay threshold is assumed to 20,000,000KRW. Results : In the base case analysis, BJT treatment resulted is better outcomes as low cost, so BJT is dominant medicine and BBT is dominated. But both cost per QALYs (BJT is 3,120,339KWN per QALY, BBT is 3,505,780KWN per QALY) are lower than the threshold, that could be covered by Korean National Health Insurance(KNHI). Conclusion : This study results showed that BJT was more cost-effective than BBT treating tinnitus patients for 10 weeks, and the cost per QALYs of both alternatives were lower than Korean national threshold.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.375-385
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• 2015

This study aims to identify geographical variations and factors that affect smoking rates. The data are collected from the Community Health Survey conducted between 2009 and 2011 by Korea Centers for Disease Control and Prevention and other government organizations. Correlation and multiple regression analysis were used to examine the factors influencing smoking rates. For the purpose of investigating regional variations, we employed a decision tree model. The study has found that the significant factors associated with geographical variations in the smoking rates were the rate of hazardous drinking, the completion rate of hypertension education, the experience rate of anti-smoking campaigns, stress awareness rate, hypertension prevalence, health insurance cost, diabetes prevalence, obesity rate, and strength training rate. Convergence-based analysis on geographical variations of the smoking rates is highly important when the regionally customized healthcare programs is implemented. In the future, it is necessary to develop effective program and customized approach for the regions of high smoking rates. Our study is expected to be used as meaningful data for the design of effective health care programs and assessments to lead effective non-smoking program.

• Journal of the Korean Data and Information Science Society
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• v.28 no.5
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• pp.1069-1076
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• 2017

Recently, with the development of advanced medical technology and the introduction of most advanced medical equipments, life expectancy increases accordingly. Many people want to live long-lived in health. Therefore, if it is possible to pre-diagnose the sub-health condition and formulate an appropriate treatment plan, we can prevent the disease and reduce social expenditure costs. In this study, we statistically analyzed the data in responding to each questionnaire for healthy biorhythm and sub-health among targeted members of a specific group. The analysis for the effects of healthy biorhythm to male and female showed that there was a significant difference between male and female. In the analysis of the effects of the conditions of healthy biorhythm to the 10 sub-health indicators, the significant effects of good and bad condition has been observed. The results of the decision tree analysis showed that all the respondents with poor hormone and urological sub-health status have bad healthy biorhythms. In summary, in this paper we have shown that it may be possible to improve the sub-health condition and prevent disease in advance if the healthy biorhythm is well controlled.

• The Journal of Engineering Geology
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• v.32 no.2
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• pp.221-239
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• 2022

Unknown geotechnical characteristics are key challenges in the design of piles for the plant, civil and building works. Although the N-values which were read through the standard penetration test are important, those N-values of the whole area are not likely acquired in common practice. In this study, the N-value is predicted by means of regression analysis with artificial intelligence (AI). Big data is important to improve learning performance of AI, so circular augmentation method is applied to build up the big data at the current study. The optimal model was chosen among applied AI algorithms, such as artificial neural network, decision tree and auto machine learning. To select optimal model among the above three AI algorithms is to minimize the margin of error. To evaluate the method, actual data and predicted data of six performed projects in Poland, Indonesia and Malaysia were compared. As a result of this study, the AI prediction of this method is proven to be reliable. Therefore, it is realized that the geotechnical characteristics of non-boring points were predictable and the optimal arrangement of structure could be achieved utilizing three dimensional N-value distribution map.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.230-231
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• 2019

This study is a development on condition based maintenance(CBM) technology which is a core item of future autonomous ships. It is developing to design & installation of condition monitoring system and acquisition & processing of data from ongoing ships for fault prediction & prognosis of engine in operation. The ultimate goal of this study is to develop a predicts and decision support software for marine engine faults. To do this, the FMEA and fault tree analysis of the main engine should be accompanied by the analysis of classification of system, identification of the components, the type of faults, and the cause and phenomenon of the failure. Finally, the CBM system solution software could predict and diagnose the failure of main engine through integrated analysis for bid-data of ongoing ships and engineering knowledge. Through this study, it is possible to pro-actively cope with abnormal signals of engine and to manage efficiently, and as a result, expected that marine accident and ship operation loss during navigation will be prevented in advance.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.6
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• pp.123-138
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• 2017

This study aims to identify the characteristic variables of businesses that would impact the choice of their type in the 6th industry and analyze how they work. To this end, this study analyzed data of 752 businesses certified as belonging to the 6th industry in 2015 through the classification and regression tree (CART) algorithm in decision tree analysis. The results of analysis showed that the type of agricultural product processing affected shaping the type of the 6th industry at the early stage of growth while the type of agricultural product processing, the type of service, region and sales volumes at the stage of growth and service strategy and the type of agricultural product processing at the stage of maturity. These findings empirically identified key business factors that could support businesses in the 6th industry at each stage of growth and presented a direction forward for support of the 6th industry.

• Journal of Information Technology Applications and Management
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• v.19 no.1
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• pp.85-100
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• 2012

The development of technology causes a lot of change. Many researchers have insisted that the proliferation of cyber space changes the physical space. Their insistences have been accumulated into three aspects. Firstly, the proliferation of cyber space brings out the concentration in the physical space, secondly the decentralization and lastly both at the same time. In Korea, the concentration of plastic surgery clinics has taken place in Kangnam-gu area at similar period of the Internet proliferation. In this research, we execute empirical study of whether the concentration of plastic surgery in specific areas correlates with the proliferation of cyber space or not. In order to do this, we verified homogeneity of plastic surgery websites between Kangnam-gu and Non-Kangnam-gu areas. Also, we used three statistical and data-mining techniques which are Multi-discriminant analysis, Decision tree analysis and artificial neural network analysis. As a result, there was homogeneity between two different area plastic surgery clinics websites, but there was not big heterogeneity as well. Therefore, in this case of concentration of plastic surgery in Korea, the proliferation of cyber space restrictively correlates with the concentration of physical space.