• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.51
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• pp.151-161
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• 1999

For many decades, Deterministic DCF approach has been widely used to evaluate investment opportunities. Under new manufacturing conditions involving uncertainty and risk, the DCF approach is not appropriate. In DCF, Risk is incorporated in two ways: certainty equivalent method, risk adjusted discount rate. This paper proposes a determination method of the Risk Adjusted Discount Rate for economically decision making advanced manufacturing technologies. Conventional DCF techniques typically use discount rate which do not consider the difference in risk of differential investment options and periods. Due to their relative efficiency, advanced manufacturing technologies have different degree of risk. The risk differential of investments is included using $\beta$ coefficient of capital asset pricing model. The comparison between existing and proposed method investigated. The DCF model using proposed risk adjusted discount rate enable more reasonable evaluation of advanced manufacturing technologies.

• Journal of the Korean Society for Railway
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• v.12 no.2
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• pp.260-266
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• 2009

The theory of risk is applied frequently in analysis of railway accidents. The aim of risk analysis is to search potential causes and contribution factors of accidents by checking the total system of construction field. This paper analyze a pattern and a cause of accident occupied in construction field, calculate risk index considering accident frequency and severity, and then provide the relative risk assessment. Based on this, this paper will provide the methodology of qualitative risk assessment guiding to reach a consistency of risk index with risk assessment.

• Environmental Mutagens and Carcinogens
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• v.23 no.1
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• pp.23-29
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• 2003

To determine the frequencies of the genotypes of estrogen metabolising enzyme (CYP17, CYP1A1, CYP1B1, and COMT) and to identify the high-risk genotypes of these metabolic enzymes to breast cancer in Korean, the author has analysed 115 breast cancer patients and corresponding age and sex matched heathy controls using polymerase chain reaction-restiction fragment length polymorphism (PCR-RFLP). A2/A2 genotype in CYP17 polymorphism, m2/m2 genotype in CYP1A1 polymorphism, and Val/Val genotype in CYP1B1 had 0.95, 1.40 and 0.76 relive risks to breast cancer comparing with reference genotypes of each polymorphism, respectively. Among the genotypes of COMT enzyme polymorphism, L/H and L/L genotypes had 0.97 and 1.54 relative risks to breast cancer, respectively. According to the number of high risk genotype, the patients with one or two putative high risk genotypes had 0.95 and 1.94 relative risks to breast cancer, respectively. This study have demonstrated the unique frequency of genotypes of estrogen metabolizing enzyme in Korean healthy women, which will provide the basic data and insights to study the estrogen related conditions in Korean women including breast and endometrial cancers. And it also indicates that the well-known high risk genotypes of estrogen metabolizing enzymes are not significantly associated with the development of breast cancer in Korean women.

• Journal of Korean Society for Quality Management
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• v.45 no.1
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• pp.139-152
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• 2017

Purpose: The purpose of this study is how Chinese users' personal traits affect the intention to use mobile payment. This research selects personal innovativeness and habit of cash payment as personal traits, and considers perceived risks and relative advantage as personal beliefs. In addition, the research divided perceived risks into three multi-faceted risks, which are privacy risk, financial risk and performance risk. Methods: The method of this study used questionnaire survey to collect 241 data on users' perception on mobile payment, and also used a structural equation modeling method. Results: The result of this paper shows that all hypotheses are statistically significant except 4 hypotheses. Conclusion: The result of this study found that personal innovativeness is negatively related with all 3 kinds of perceived risks as anticipated. And Chinese users' traditional habit of cash payment negatively affects intention to use mobile payment but is not statistically significant affecting three perceived risks. Among perceived risks, privacy risk is the most negatively influencing factor to relative advantage.

• Korean Journal of Adult Nursing
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• v.29 no.1
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• pp.1-11
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• 2017

Purpose: The purpose of this study was to identify the factors and the relative risk associated with admission of patients with diabetes mellitus (DM). Methods: The sample included one hundred twenty-eight patients with type II DM. Seventy-seven patients who were admitted within six months of a hospitalization to one hospital from the first of February to the 31st of August 2014, were compared with fifty-one patients who regularly attended an outpatient clinic and had no hospitalizations. Results: Hospitalization probabilities among patients who had only diet and exercise or took oral diabetic medication were 0.03 (p=.004) and 0.21 (p=.007) times independently lower than the ones with insulin injection. The risks for hospitalization increases 6.33 times if there is absence of a spouse (p=.027) whereas the presence of a spouse seems to make hospitalization less likely. The risk among the ones having diabetic complications was 5.15 times higher than ones having no recognition of the complications (p=.040). For every one point increase in self-efficacy and every 1 mg/dL increase in high density lipoprotein (HDL) cholesterol, there was a 0.84 (p=.005) and a 0.96 (p=.036) decrease in hospitalization risk, respectively. Conclusion: Nurses should be sensitive to the risk groups of hospital admission among patients with DM including no spouse, insulin injection, diabetic complications, low self-efficacy, and low HDL cholesterol.

• Safety and Health at Work
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• v.13 no.1
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• pp.73-77
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• 2022

Background: Whole-body vibration (WBV) exposure of coal mine dumper operators poses numerous health hazards. The case-control study was aimed at assessing the relative musculoskeletal health risk of dumper operators' exposure to WBV with reference to the nonexposed group. Methods: Measurements of WBV exposure were taken at the operator-seat interface using a human vibration analyzer for 110 dumper operators in three coal mines. This vibration measurement was supplemented by a questionnaire survey of 110 dumper operators exposed to WBV and an equal number of workers not exposed to WBV. The relative risk of musculoskeletal disorders (MSDs) has been assessed through the case-control study design. Results: ISO guidelines were used to compare the health risk. It was observed that the prevalence of pain in the lower back was 2.52 times more in the case group compared to the control group. The case group of Mine-2 was 2.0 times more prone to vibration hazards as compared to Mine-3. Conclusion: The case group is more vulnerable to MSDs than the control group. The on-site measurement as well as the response of the dumper operators during the questionnaire survey corroborates this finding.

• Environmental Engineering Research
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• v.12 no.4
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• pp.129-135
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• 2007

This study evaluated microbial risk that could develop within soil microbial communities after amended with organic fertilizers from stabilized swine manure waste. For this purpose, we assessed the occurrences and competitiveness of antibiotic resistance and pathogenicity in soil microbial communities that were amended with swine manure wastes stabilized by a traditional lagoon fermentation process and an autothermal thermophilic aerobic digestion process, respectively. According to laboratory cultivation detection analysis, soil applications of the stabilized organic fertilizers resulted in increases in absolute abundances of antibiotic resistant bacteria and of two tested pathogenic bacteria indicators. The increase in occurrences might be due to the overall growth of microbial communities by the supplement of nutrients from the fertilizers. Meanwhile, the soil applications were found to reduce competitiveness for various types of antibiotic resistant bacteria in the soil microbial communities, as indicated by the decrease in relative abundances (of total viable heterotrophic bacteria). However, competitiveness of pathogens in response to the fertilization was pathogens-specific, since the relative abundance of Staphylococcus was decreased by the soil applications, while the relative abundance of Salmonella was increased. Further testes revealed that no MAR (multiple antibiotic resistance) occurrence was detected among cultivated pathogen colonies. These findings suggest that microbial risk in the soil amended with the fertilizers may not be critical to public health. However, because of the increased occurrences of antibiotic resistance and pathogenicity resulted from the overall microbial growth by the nutrient supply from the fertilizers, potential microbial risk could not be completely ruled out in the organic-fertilized soil samples.

• Health Policy and Management
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• v.18 no.4
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• pp.49-65
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• 2008

The single-item question of self-assessed health status has consistently been reported to be associated with mortality in some developed countries, even after controlling for a wide range of health measurements and known risk factors for. mortality. It was intended in this study to find out whether or not such a relationship would also be valid in Korea. This study examined the effect of point of reference year on. the, predictive validity of self-assessed health for mortality in 6-year follow-up period. we need to test the validity of the self-assessed health, as an indicator for assessing health status using Cox's proportional hazard model. For the analysis, we used the data from the 2nd (1999) to the 7th survey of "Korean Labor and Income Panel Study," and assessed relative risk of death based on subjective health state by tracing 11,366 people who replied to the question of self-assessed health state in the 2nd year. According to the result, those who reported poor self assessed health state in the 2nd year showed a relatively high death rate, and their relative risk of death was significantly higher. Such a relationship was accentuated if the predictive value of the 2nd survey result would be replaced by the average of the cumulative data on the past six years. Thus, it can be concluded that self-assessed health state is valid as an index for assessing Korean people's health status.

• Korean Journal of Community Nutrition
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• v.9 no.6
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• pp.695-705
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• 2004

The risks of the metabolic syndrome (MS) is known to be related to the dietary behavior. The objective of this study is to evaluate the association between the relative risks of MS and the dietary habit and to provide the ideal dietary habits for prevention of chronic disease of the middle-aged. Healthy subjects aged 40-64 years (male n=122, female n=173) were recruited throughout Seoul area. MS was defined according to NCEP-ATP III criteria except central obesity, and Asia-Pacific Area criteria for central obesity (2000) was adapted. Subjects were stratified into 3 groups according to the number of total risk factors:'MS group' was defined as the subjects who have three or more risk factors, 'Risk group' was defined as ones to have one or two risk factors, and 'Healthy group' defined as ones with no risk factor. In this study, 'Health group' comprised of $40.7\%$, the percentage of 'Risk group' was $49.0\%$, and the 'MS group' was $9.5\%$ of the total subjects. The MS incidence was associated with low education (p<0.001), low economic status (p<0.05), and low self-assessed health recognition (p<0.05). The risk of MS increased with adverse life styles such as cigarette smoking (p<0.05), irregular meal time (p<0.05), skipping lunch (p<0.05), low interests in balanced diet (p<0.05), and higher salt intake (p<0.01). Healthy group self-evaluated nutritional knowledge more highly (p<0.05) and scored higher nutritional knowledge (p<0.001). However, there was no difference in overall nutritional behavior among the three groups, which implies that nutritional education method should be developed for the subjects to practice their teaming efficiently.

• Journal of Korean Society for Quality Management
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• v.50 no.1
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• pp.125-138
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• 2022

Purpose: Failure Mode and Effect Analysis (FMEA) is a widely utilized technique to measure product reliability by identifying potential failure modes. Even though FMEA techniques have been studied, the form of Risk Priority Number (RPN) used to evaluate risk priority in FMEA is still questionable because of its shortcomings. In this study, we suggest common RPN(cRPN) to resolve shortcomings of the traditional RPN and show the extensibility of cRPN. Methods: We suggest cRPN which is based on Cobb-Douglas production function, and represent the various application on weighting risk factors, weighted RPN in a mathematical way, and show the possibility of statistical approach. We also conduct numerical study to examine the difference of the traditional RPN and cRPN as well as the potential application from the analysis on marginal effects of each risk factor. Results: cRPN successfully integrates previously suggested approaches especially on the relative importance of risk factors and weighting RPN. Moreover, we analyze the effect of corrective actions in terms of econometric analysis using cRPN. Since cRPN is rely on the reliable mathematical model, there would be numerous applications using cRPN such as smart factory based on A.I. techniques. Conclusion: We propose a reliable mathematical model of RPN based on Cobb-Douglas production function. Our suggested model, cRPN, resolves various shortcomings such as consideration of the relative importance, the effect of combinations among risk factors. In addition, by adopting a reliable mathematical model, quantitative approaches are expected to be applied using cRPN. We find that cRPN can be utilized to the field of industry because it is able to be applied without modifying the entire systems or the conventional actions.