• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.4
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• pp.107-115
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• 2020

Support vector regression (SVR) is devised to solve the regression problem by utilizing the excellent predictive power of Support Vector Machine. In particular, the ⲉ-insensitive loss function, which is a loss function often used in SVR, is a function thatdoes not generate penalties if the difference between the actual value and the estimated regression curve is within ⲉ. In most studies, the ⲉ-insensitive loss function is used symmetrically, and it is of interest to determine the value of ⲉ. In SVQR (Support Vector Quantile Regression), the asymmetry of the width of ⲉ and the slope of the penalty was controlled using the parameter p. However, the slope of the penalty is fixed according to the p value that determines the asymmetry of ⲉ. In this study, a new ε-insensitive loss function with p1 and p2 parameters was proposed. A new asymmetric SVR called GSVQR (Generalized Support Vector Quantile Regression) based on the new ε-insensitive loss function can control the asymmetry of the width of ⲉ and the slope of the penalty using the parameters p1 and p2, respectively. Moreover, the figures show that the asymmetry of the width of ⲉ and the slope of the penalty is controlled. Finally, through an experiment on a function, the accuracy of the existing symmetric Soft Margin, asymmetric SVQR, and asymmetric GSVQR was examined, and the characteristics of each were shown through figures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3789-3798
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• 2014

This study examined the factors affecting blood donation intention and behavior in college students based on the theory of planned behavior. The subjects were 258 students from one college in G city, and the data was collected by a survey using self-administered questionnaires structured from June 3 to June 14, 2013. The data was analyzed using the SPSS 19.0 program, the variables affecting the blood donation intention were analyzed by stepwise multiple regression, and the variables affecting the blood donation behavior were analyzed by Logistic regression. The factors affecting the blood donation intention were in order the perceived behavioral control, attitude toward the behavior and subjective norm, and the explanatory power was 65.6%. In addition, the factor affecting the blood donation behavior was only the blood donation intention (OR=1.129, p=.010) except for perceived behavioral control. Therefore, the perceived behavioral control, attitude and subjective norm should be considered when developing blood donation programs for college students.

• Journal of the Korea Convergence Society
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• v.8 no.5
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• pp.117-125
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• 2017

This is a convergence study to present strategies for performance enhancement by verifying the causal relationship between the influencing factor on the performance of the healthcare-associated infection control guidelines in hospital nurses. Participants were 388 nurses recruited from 16 different tertiary and general hospitals in Korea. Data collection was conducted using self-report questionnaires and analyzed using SPSS 21.0 and AMOS 21.0 programs. The overall fitness was ${\chi}^2=99.64$ (df=14, p<.01), GFI=.94, RMSEA=.10, NFI=.84, CFI=.90. The explanatory power of predictive variables on intention were 23.8%, and those on behavior were 17.7%. As a result of this study, it was found that TPB is an appropriate theory to explain the performance of healthcare-associated infection control guidelines, and repeated studies including multi-level modeling of career experience and organizational influences on behavior with strong social characteristics are needed.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.5
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• pp.1-13
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• 2009

Filter cache has been introduced as one solution of reducing cache power consumption. More than 50% of the power reduction results from the filter cache, whereas more than 20% of the performance is compromised. To minimize the performance degradation of the filter cache, the predictive filter cache has been proposed. In this paper, we review the previous filter cache predictors and analyze the problems of the solutions. As a result, we found main problems that cause prediction misses in previous filter cache schemes and, to resolve the problems, this paper proposes a new prediction policy. In our scheme, some reference bit entries, called MSBs, are inserted into filter cache and BTB, to adaptively control the filter cache access. In simulation parts, we use a modified SimpleScalar simulator with MiBench benchmark programs to verify the proposed filter cache. The simulation result shows in average 5% performance improvement, compared to previous ones.

• International Journal of Control, Automation, and Systems
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• v.1 no.2
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• pp.194-202
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• 2003

In this paper, we introduce a category of Multi-FNN (Fuzzy-Neural Networks) models, analyze the underlying architectures and propose a comprehensive identification framework. The proposed Multi-FNNs dwell on a concept of fuzzy rule-based FNNs based on HCM clustering and evolutionary fuzzy granulation, and exploit linear inference being treated as a generic inference mechanism. By this nature, this FNN model is geared toward capturing relationships between information granules known as fuzzy sets. The form of the information granules themselves (in particular their distribution and a type of membership function) becomes an important design feature of the FNN model contributing to its structural as well as parametric optimization. The identification environment uses clustering techniques (Hard C - Means, HCM) and exploits genetic optimization as a vehicle of global optimization. The global optimization is augmented by more refined gradient-based learning mechanisms such as standard back-propagation. The HCM algorithm, whose role is to carry out preprocessing of the process data for system modeling, is utilized to determine the structure of Multi-FNNs. The detailed parameters of the Multi-FNN (such as apexes of membership functions, learning rates and momentum coefficients) are adjusted using genetic algorithms. An aggregate performance index with a weighting factor is proposed in order to achieve a sound balance between approximation and generalization (predictive) abilities of the model. To evaluate the performance of the proposed model, two numeric data sets are experimented with. One is the numerical data coming from a description of a certain nonlinear function and the other is NOx emission process data from a gas turbine power plant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1157-1163
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• 2013

The purpose of this study is to investigate the relationship among self-efficacy, self-determinative motivation and creative thinking ability. And to confirm the relative predictive power of motivation variables in predicting middle school students' creative thinking ability. The instruments used in this study were 'TTCT', 'Self-efficacy' and 'Self-Regulation Scale'. Self-reported response data on these instruments from 212 middle school students in Seoul were analyzed. The data were analyzed with descriptive statistics, Pearson correlations, multiple stepwise regression analysis by using SPSS 18.0. The major results of this study were as follows; First, the correlations among self-efficacy, self-determinative motivation and creative thinking ability were significant. Second, Task difficulty preferred, self-control efficacy and internal motivation were the best predictor of creative thinking ability in middle school students. This study suggested that Task difficulty preferred, self-control efficacy and internal motivation is essential to improve creative thinking ability in middle school students.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1148-1156
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• 2013

The purpose of this study is to investigate the relationship among self-efficacy, motivation proposed by self-determination theory and academic achievement and to confirm the relative predictive power of motivation variables in predicting 480 middle/high students' achievement. The instruments used in this study were 'Self-efficacy' and 'Self - regulation' scale. The data were analyzed with Pearson correlations and multiple regression (stepwised) analysis. The correlations among self-efficacy, self-determination motivation and academic achievement were significant. The variables among self-determination were correlated to academic achievement in middle school. Among the variables of self-determination motivation, identified regulation, Integrated regulation and intrinsic regulation were positively related to academic achievement in high school but amotivation was negatively related to academic achievement. Self-control efficacy and self-confidence were the significance predictor of academic achievement in middle school. Hard-task preference and self-control efficacy were the significance predictor of academic achievement in high school students. Introjected-regulation was the best predictor of academic achievement in middle school. Identified-regulation was the best predictor of academic achievement in high school.

• Safety and Health at Work
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• v.15 no.1
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• pp.59-65
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• 2024

Background: Different job strain formulations based on the Job Demand-Control model have been developed. This study evaluated longitudinal associations between job strain and psychological distress and whether associations were influenced by six formulations of job strain, including quadrant (original and simplified), subtraction, quotient, logarithm quotient, and quartile based on quotient, in randomly selected Japanese workers. Methods: Data were from waves I and II of the Survey of Midlife in Japan (MIDJA), with a 4-year followup period. The study sample consisted of 412 participants working at baseline and had complete data on variables of interest. Associations between job strain at baseline and psychological distress at follow-up were assessed via multivariable linear regression, and results were expressed as β coefficients and 95% confidence intervals including R² and Akaike information criterion (AIC) evaluation. Results: Crude models revealed that job strain formulations explained 6.93-10.30% of variance. The AIC ranged from 1475.87 to 1489.12. After accounting for sociodemographic and behavioral factors and psychological distress at baseline, fully-adjusted models indicated significant associations between all job strain formulations at baseline and psychological distress at follow-up: original quadrant (β: 1.16, 95% CI: 0.12, 2.21), simplified quadrant (β: 1.01, 95% CI: 0.18, 1.85), subtraction (β: 0.39, 95% CI: 0.09, 0.70), quotient (β: 0.37, 95% CI: 0.08, 0.67), logarithm quotient (β: 0.42, 95% CI: 0.12, 0.72), and quartile based on quotient (β: 1.22, 95% CI: 0.36, 2.08). Conclusion: Six job strain formulations showed robust predictive power regarding psychological distress over 4 years among Japanese workers.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.357-366
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• 2009

The principal objective of this study was to evaluate the association between plasma antioxidant levels and metabolic syndrome in male workers, and to provide basic information regarding the control and prevention of metabolic syndrome. We analyzed 163 male workers who had participated in annual medical examinations from January to December 2007. The subjects were classified into normal and metabolic syndrome groups according to the NCEP-ATP III criteria and the Asia-Pacific criteria for waist circumference. Anthropometric parameters, lifestyles, blood lipid profiles, and antioxidant levels were evaluated. As compared to the normal group, the metabolic syndrome group evidenced significantly higher plasma levels of $\alpha$- tocopherol(p<0.05) and retinol(p<0.05), but significantly lower plasma levels of lycopene(p<0.05) and $\beta$-carotene(p<0.05). This tendency was found to be predominantly attributable to increases in the number of metabolic syndrome components. In our simple regression analysis, higher plasma levels of $\alpha$-tocopherol($\beta$=0.001, p<0.01) and retinol($\beta$=0.021, p<0.001) were associated with significantly higher risks of metabolic syndrome, but lycopene($\beta$=-1.499, p<0.01) and $\beta$-carotene($\beta$=-0.048, p<0.01) were associated with significantly lower risks of metabolic syndrome. Retinol($\beta$=0.013, p<0.05) and $\beta$-carotene($beta$=-0.044, p<0.01) were associated significantly with metabolic syndrome, when adjusted for age and BMI. These data indicate that the plasma levels of $\alpha$-tocopherol, retinol, lycopene, and $\beta$-carotene are associated with metabolic syndrome. Specifically, low lycopene and $\beta$-carotene levels in the plasma appear to increase the risk of metabolic syndrome. Therefore, proper nutritional education programs for male workers are required to increase dietary intakes of antioxidant vitamins. Further studies will be necessary to determine whether antioxidant levels can be utilized as a predictive or a preventive factor.

• Fire Science and Engineering
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• v.24 no.6
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• pp.133-138
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• 2010

This study is aimed to investigate the relationship between job-related stressor, problem solving style and psychological distress and the effects of job-related stress and problem solving style on psychological distress of firefighters. The Job-related Stress Scale, Problem Solving Style Questionnaire, and the Symptom Checklist-Revised (SCL-90-R) were administered to 148 firefighters working in Seoul and Gyounggi. Correlation analysis revealed that job-related stress, problem-solving styles such as helplessness and problem-solving control correlated positively with psychological distress and that problem-solving confidence and approaching style correlated negatively with it. Multiple regression analysis showed that job-related negative cognition and emotion, helplessness and approaching style accounted for 43% of the variance in the psychological distress. Among problem-solving styles, helplessness had the highest predictive power for psychological distress. Self-reported helplessness is an important determinant of firefighters' reactions to problematic situations encountered in their job.