• Journal of Korea Artificial Intelligence Association
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• v.1 no.2
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• pp.21-25
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• 2023

The purpose of this study was to compare the performance using multiple regression models to predict the energy consumption of steel industry. Specific independent variables were selected in consideration of correlation among various attributes such as CO2 concentration, NSM, Week Status, Day of week, and Load Type, and preprocessing was performed to solve the multicollinearity problem. In data preprocessing, we evaluated linear and nonlinear relationships between each attribute through correlation analysis. In particular, we decided to select variables with high correlation and include appropriate variables in the final model to prevent multicollinearity problems. Among the many regression models learned, Boosted Decision Tree Regression showed the best predictive performance. Ensemble learning in this model was able to effectively learn complex patterns while preventing overfitting by combining multiple decision trees. Consequently, these predictive models are expected to provide important information for improving energy efficiency and management decision-making at steel industry. In the future, we plan to improve the performance of the model by collecting more data and extending variables, and the application of the model considering interactions with external factors will also be considered.

• The Journal of the Convergence on Culture Technology
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• v.8 no.2
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• pp.91-97
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• 2022

This study was conducted to understand the degree of personality and interpersonal relationships among dental hygiene students. The survey was conducted from April 1, 2021 to June 30, 2021. As a result of the study, personality was 3.42 points and interpersonal relationships were 3.46 points. In general, there was a statistically significant difference in both personality and interpersonal subdomains in interpersonal satisfaction and college life satisfaction (p<.05, p<.001). The more experience they had in clinical practice, the lower their scores for friendship and professorship among interpersonal relationships. Among the sub-domains of personality, morality and sociality were analyzed as having the highest positive correlation (r=.674), and in interpersonal relationships, the relationship between friends and professors was analyzed as high (r=.606). Therefore, for the holistic growth of dental hygiene students as preliminary dental hygienists and their adaptation to the dental care field, a long-term strategy and continuous educational approach are needed at the university for cultivating character and interpersonal relationships, which are the basics. In addition, various programs related to the duties of dental hygienists should be developed and methods to be applied should be sought.

• Journal of Korean Society of Transportation
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• v.27 no.2
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• pp.57-71
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• 2009

Due to increasing interest in dispersion of traffic flows through providing traffic information, there has been much research of driver behavior and effectiveness of diversion. In this paper the authors intend to analyze how a diversion was determined and its effects through correlation analysis between diversion rates estimated by actual surveys and the traffic conditions. Through speed-flow analysis, the diversion mechanism was found. When travel speed decreased, detour volume increased. Then when the traffic volume was decreased through an increase of diversion and traffic conditions got better, the detour volume decreased again. In addition, the authors found negative correlation between the diversion rate and travel speed through correlation analysis. It shows that there were various relationships between diversion rates and traffic conditions according to congestion level and direction of traffic. Finally, it is suggested that the regression equation for calculating the diversion rate with the traffic flows, travel speed, and travel time as variables has a coefficient of determination of 38.5%. It means that traffic conditions on expressways take about 40% of driver's decision-making for diversion.

• Journal of muscle and joint health
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• v.11 no.1
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• pp.50-60
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• 2004

Purpose: The purpose of this study was to examine the relationships among the health promoting behavior, pain, self-esteem, family support, self-efficacy in patients with chronic arthritis. Method: The data for this study were collected from February 19, 2003 to April 7, 2003. The subjects were 150 chronic arthritis patients who visited University Hospital in D City. The research instruments used in this study were HPLP II, Visual analogue scale, Self-esteem scale, Family support scale, Self-efficacy scale. In data analysis, SPSS PC ver 10.0 program was utilized and data were analyzed using descriptive statistics and t-test, ANOVA, Multiple Stepwise Regression and Pearson's correlation coefficient. Result: The average score of the pain, self-esteem, family support, self-efficacy, health promoting behavior was 5.38, 3.37, 4.29, 70.30, 2.68, respectively and the variable with the highest degree of it's subscale was interpersonal support(3.08), whereas the one with the lowest degree was exercise(1.66). There was a positive correlation(r=.327, p=.000) between the self-esteem and health promoting behavior. There was a positive correlation(r=.540, p=.000) between the family support and the self-efficacy and health promoting behavior. Family support, self-efficacy and marital status were significant factors to explain a variance of health promoting behavior in patients with chronic arthritis(51.6%). health promoting behavior. There was a positive correlation(r=.477, p= .000) between Conclusion: The health promoting behavior were positively correlated with self-esteem, family support and self-efficacy. These findings help to understand relationships among self-esteem, family support and self-efficacy in chronic arthritis patients. In addition, family support, self-efficacy and marital status were the mainly influencing factors of health promoting behavior. Among these variables family support was the most significant factor to predict a health promoting behavior. According to the results of this study, family support must be considered as a main factor in the nursing strategy for health promoting behavior of chronic arthritis patients.

• Journal of Oriental Neuropsychiatry
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• v.21 no.4
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• pp.175-185
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• 2010

Objectives : The objective of this study was to observe the relationships between neck pain and psychological factors such as stress, anger, anxiety and depression. Methods: Under mental stress. the 31 patients with neck stiffness and 32 control subjects with no neck stiffness were measured by using NDI, BEPSI, GARS, STAXI, STAI, and BDI scales. The psychological scales between the patients and the controls were taken to observe the average results by comparing between the two groups. Also NDI and psychological scales of correlation analysis was performed. Results: 1. The mean scores of NDI, BEPSI, GARS, State-Anger, Trait-Anger, Anger-out, Anger-In, Sate-Anxiety, TraitAnxiety, and BDI under patients group were significantly higher than those in control group. 2. The value of NDI comparing to the values of BEPSI, GARS, State-Anger, Trait-Anger, Anger-out, Anger-In, Sate-Anxiety, Trait-Anxiety, and BDI in this study resulted in high correlation among each others which showed statistically significant. Conclusions : It has the possibility that the neck pain with stress. anxiety. anger and depression might be related highly in correlation. especially in stress and anxiety which showed the most high correlation.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.4
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• pp.253-263
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• 2019

Purpose : The purpose of this study was to identify the self-efficacy, major satisfaction, and degree of adjustment to college life of nursing students and the relationships among the foregoing. Methods : This study was conducted with 319 nursing students in B city from May to June 2019. The collected data were analyzed with frequency, percentage, mean and standard deviation, t-test, ANOVA, Scheffe's test, and Pearson Correlation Coefficient using the SPSS /WIN 22.0 program. Results : The self-efficacy score of nursing college students was shown to be 2.95±0.32 points, major satisfaction score was shown to be 3.83±0.55 points, and college adjustment score was shown to be 3.52±0.55 points. The degrees of adjustment to college life were significantly different according to general characteristics of nursing students as follows; grade (F=6.614, p=.000), health condition (F=13.384, p=.000), club activities (t=4.557, p=.000), happiness index (F=32.094, p=.000), part-time job (t=2.781, p=.006), and motive of major selection (F=7.300, p=.000). The adjustment to college life of nursing students showed a weak negative correlation with self-efficacy (r=-.196, p<.001) and a strong positive correlation with major satisfaction (r=.782, p<.001). Major satisfaction and self-efficacy showed a weak negative correlation (r=-.185, p<.001). Conclusion : Through the results of this study, it can be seen that repetitive studies are necessary in relation to the self-efficacy, major satisfaction, and college adjustment of nursing students, and that interest in effort for the development of programs that can improve nursing students' major satisfaction and college adjustment are necessary.

• Plant Resources
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• v.6 no.2
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• pp.134-139
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• 2003

This study was conducted to investigate the relationships between yearly variations of meteorological elements and yearly variations of productivity in rice. In addition, correlation coefficients among yield and yield components were used to find out the relationships between meteorological elements and productivity. Yearly variation of the mean air temperature in May was large with coefficients of variation(C.V.) of 25.0%, but the variation of the duration of sunshine in May were relative small. No. of panicles per hill and 1,000 grains wt. of brown rice were great with C.V. of 21.1, 19.7%, respectively, brown rice yield show more or less C.V. of 5.5% and milled rice show still less variation. Correlation coefficients between temperatures in period of cultivation from May and yield were positive correlations. Correlation Coefficients between precipitation in period of cultivation from Sep. to Oct. and yield are positive correlations. Correlation coefficients amount the panicle length, no. of panicles, no. of spikelets, ratio of ripened grains, 1,000 grains wt. of brown rice, milled rice yield, brown rice yield and milled rice yield were positively significant at the level of 1 %, respectively.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1306-1310
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• 2009

The roughness coefficients were estimated by the Manning's equation for the measured stage and flow velocity of Bocheong stream basin in Kum river. The relationships between the estimated roughness coefficients and the geomorphologic factors were formulated by the linear, logarithmic, exponential and power type function, thereafter correlation equations were presented. The correlation analysis was performed between the measured stream length and the basin area of Bocheong stream basin by the linear, logarithmic, exponential and power type function, and correlation equation for the stream length was given. The roughness coefficient has strong correlationship with stream slope, but low correlation coefficients with stream length and basin area. For the correlationship with the roughness coefficients and the stream slope, the logarithmic type function has the smallest correlation coefficient, on the other hand, the exponential type function has the largest correlation coefficient. For the relationship between the stream length and the basin area, the correlation coefficient of the logarithmic type function shows the smallest value, linear type function shows the largest value.

• Journal of Environmental Health Sciences
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• v.16 no.2
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• pp.55-61
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• 1990

Laboratory methods commonly used today are biochemical oxygen demand, chemical oxygen demand, and total organic carbon. Establishment of constant relationships among the various measures of organic content depends primarily on the nature of the wastewater and its source. Of all the measures, the most difficult to correlate to the others is the BODs test, because of the problems associated with biological tests. The results were summarized as follwos, 1. For typical municipal wastes, however, the SBOD$_{5}$/SCOD$_{cr}$ ratio varies from 0.14 to 0.34(mean 0.21), SBOD$_{5}$/STOC ratio varies from 0.35 to 1.19(mean 0.69) 2. Correlation analysis between the SBOD$_{5}$ and SCOD$_{cr}$ gave good correlation coefficient r = 0.903 and the equation Y = 3.756X + 16,221 was obtained. 3. The correlation between the SBOD$_{5}$ and STOC was well presented with equation : Y = 1,070X + 7,637, and also correlation coefficient r = 0.821 4. The correlation between the SCOD$_{cr}$ and STOC was well presented with equation : Y = 0.256X +5.513 and also correlation coefficient r = 0.816. 5. Because of the rapidity with which the TOC test can be conducted, it is anticipated that more use will be made of these tests in the future.

• Journal of Korean Society of Rural Planning
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• v.29 no.4
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• pp.55-67
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• 2023

This study investigated the correlation between impervious surface area rate(ISAR) and various urbanization indicators at the si-gun administrative level. For the years 2017 and 2021, we built correlation matrices to examine the relationships between ISAR and eight urbanization indicators, including total population, working-age population, residential power consumption, non-agricultural power consumption, paved road length, permitted development area, numbers of registered vehicles, and cadastral 'Dae' parcel area. Additionally, K-means clustering was employed to classify the 229 si-guns based on the ISAR change patterns. The analysis revealed a significant positive correlation between ISAR and urbanization indicators for both years studied. However, the interannual comparison showed a noticeably weaker correlation between changes in ISAR and urbanization indicators from 2017 to 2021. The K-means analysis also showed that si-guns with higher ISAR values, typically urban areas, demonstrated a weaker correlation, while the cluster consisting mostly of rural areas with lower ISAR displayed stronger correlations. These results suggested that ISAR should be a significant factor for consideration in sustainable rural planning and development strategies.