• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.106-106
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• 2015

The information of flow regimes continues to be norm in water resource and watershed management, in that stream flow regime is a crucial factor influencing water quality, geomorphology, and the community structure of stream biota. The objectives of this study were to estimate Korean stream flows from landscape variables, classify stream flow gages using hydraulic characteristics, and then apply these methods to ungaged biological monitoring sites for effective ecological assessment. Here I used a linear modeling approach (MLR, PCA, and PCR) to describe and predict seasonal flow statistics from landscape variables. MLR models were successfully built for a range of exceedance discharges and time frames (annual, January, May, July, and October), and these models explained a high degree of the observed variation with r squares ranging from 0.555 (Q95 in January) to 0.899 (Q05 in July). In validation testing, predicted and observed exceedance discharges were all significantly correlated (p<0.01) and for most models no significant difference was found between predicted and observed values (Paired samples T-test; p>0.05). I classified Korean stream flow regimes with respect to hydraulic and hydrologic regime into four categories: flashier and higher-powered (F-HP), flashier and lower-powered (F-LP), more stable and higher-powered (S-HP), and more stable and lower-powered (S-LP). These four categories of Korean streams were related to with the characteristics of environmental variables, such as catchment size, site slope, stream order, and land use patterns. I then applied the models at 684 ungaged biological sampling sites used in the National Aquatic Ecological Monitoring Program in order to classify them with respect to basic hydrologic characteristics and similarity to the government's array of hydrologic gauging stations. Flashier-lower powered sites appeared to be relatively over-represented and more stable-higher powered sites under-represented in the bioassessment data sets.

• Journal of the Korean Society of School Health
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• v.33 no.3
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• pp.164-174
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• 2020

Purpose: The purpose of this study was to identify the factors affecting tuberculosis prevention behaviors in North Korean adolescent refugees. Methods: From September 16 to October 8, 2019, a survey was conducted to collect data from 143 North Korean adolescent refugees aged 13 to <25 at alternative and general schools in Seoul and Gyeonggi Province. The scale developed by Park (2008) and adapted by Cha (2012) was used to rate tuberculosis prevention behaviors in daily life with the aim of preventing high school students from getting infected with tuberculosis. The collected data were processed through frequency analysis, descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and multiple linear regression, using SPSS 25.0. Results: The mean score was 13.65 for knowledge of tuberculosis, 44.23 for attitudes towards tuberculosis, and 41.33 for tuberculosis prevention behaviors. Significant differences were found according to gender, country of origin, duration of stay in South Korea, tuberculosis examination, pre-entry chest x-ray, education about tuberculosis, alcohol intake, and subjective health status. A positive correlation was found between knowledge, attitudes, and prevention behaviors. The factors affecting tuberculosis prevention behaviors were attitudes (β=.38, p<001) and subjective health status (β=.26, p<.001). Conclusion: It is necessary to provide attitude-based education that can reinforce positive attitudes in order to improve North Korean adolescent refugees' tuberculosis prevention behaviors. This is expected to help them pay more attention to health care and become better at prevention behaviors. It is, therefore, necessary to develop a tuberculosis prevention education program with the aim of making them more knowledgeable about tuberculosis and providing them with systematic and sustainable education.

• Journal of Nutrition and Health
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• v.54 no.1
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• pp.54-66
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• 2021

Purpose: Considering the various health benefits of vegetables, it is necessary to identify maternal correlates of vegetable preference and consumption in children for shaping desirable vegetable-related eating habits. This study aimed to investigate the maternal factors related to vegetable preferences and consumption in preschool-aged children. Methods: This is a cross-sectional study that surveyed 303 mother-child pairs (146 boys, 157 girls) to explore general characteristics, vegetable preferences, and cooked vegetable consumption in mothers and children using a questionnaire method. Maternal correlates of the child's vegetable preference and consumption were tested using a generalized linear model using SAS program. Results: Mothers' vegetable preferences and consumption were significantly higher than those in their children (p < 0.001). Mothers' vegetable preferences showed a significant positive correlation with the vegetable preferences of their children (mother-son, p < 0.001; mother-daughter, p < 0.001). Additionally, mothers' cooked vegetable consumption showed a significant positive correlation with the cooked vegetable consumption of children (mother-son, p < 0.001; mother-daughter, p < 0.001). Mothers' vegetable preferences and consumption respectively increased those of their children, in both boys and girls. Conclusion: Findings that mothers' vegetable preference and consumption correlates of children's vegetable preferences and consumption, indicate the importance of the mothers' role in increasing vegetable consumption in children. Mothers should be aware of the effects of their vegetable eating habits on their children's vegetable consumption and try to develop healthy eating habits. We suggest that the government or local communities provide nutrition education for mothers to adopt healthy eating habits and present information to educate their children on food and healthy dietary habits.

• Journal of Integrative Natural Science
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• v.13 no.4
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• pp.132-140
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• 2020

With the recent introduction of artificial intelligence (AI) technology, the use of data is rapidly increasing, and newly generated data is also rapidly increasing. In order to obtain the results to be analyzed based on these data, the first thing to do is to classify the data well. However, when classifying data, if only one classification technique belonging to the machine learning technique is applied to classify and analyze it, an error of overfitting can be accompanied. In order to reduce or minimize the problems caused by misclassification of the classification system such as overfitting, it is necessary to derive an optimal classification by comparing the results of each classification by applying several classification techniques. If you try to interpret the data with only one classification technique, you will have poor reasoning and poor predictions of results. This study seeks to find a method for optimally classifying data by looking at data from various perspectives and applying various classification techniques such as LDA and QDA, such as linear or nonlinear classification, as a process before data analysis in data analysis. In order to obtain the reliability and sophistication of statistics as a result of big data analysis, it is necessary to analyze the meaning of each variable and the correlation between the variables. If the data is classified differently from the hypothesis test from the beginning, even if the analysis is performed well, unreliable results will be obtained. In other words, prior to big data analysis, it is necessary to ensure that data is well classified to suit the purpose of analysis. This is a process that must be performed before reaching the result by analyzing the data, and it may be a method of optimal data classification.

• Journal of the Korea Convergence Society
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• v.12 no.6
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• pp.241-248
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• 2021

The purpose of this study was to investigate the factors affecting the rights guarantee of people with mental illness among mental care facility workers. The subjects of this study were 132 mental care facility workers, and the research tools were rights and protection-related characteristics, rights recognition, and rights guarantee. The data were analyzed with descriptive statistics, t-test, one-way ANOVA, Pearson's correlation coefficients, and multiple linear regression using the SPSS/WIN 24.0 program. The result showed that the difference in rights guarantee relating to general characteristics were significant differences in religion. There were significant positive correlations among rights recognition and rights guarantee. The factors influencing the rights guarantee were rights recognition, recognizing the need to advocate rights, and religion. Based on the research results, it is necessary to improve recognition and actively advocate rights through continuous education in order to strengthen the rights guarantee of people with mental illness. Enhancement of rights guarantee will help people with mental disorder recover.

• The Korean Journal of Applied Statistics
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• v.34 no.2
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• pp.255-266
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• 2021

The purpose of this study is to compare the effects of treatment on stage III stomach cancer data obtained from the SEER program of the National Cancer Institute and to identify the significant risk factors for the survival rates of stage III stomach cancer. Since the proportional hazards assumption was violated for treatment, we used the restricted mean survival time as an alternative to the proportional hazards model. The restricted mean survival time was estimated using pseudo-observations, and the effects of treatment were compared using a test statistic based on the estimated restricted mean survival times. We conducted the regression analysis using a generalized linear model to investigate the significant predictors for the restricted mean survival time of patients with stage III stomach cancer. We found that there was a significant difference between the restricted mean survival times of treatment groups. Age at diagnosis, race, substage, grade, tumor size, surgery, and treatment were significant predictors for the restricted mean survival time of patients with stage III stomach cancer. Surgery was the most significant predictor for increasing the restricted mean survival time of patients with stage III stomach cancer.

• Journal of Korean Biological Nursing Science
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• v.23 no.2
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• pp.100-109
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• 2021

Purpose: This study aimed to compare the differences in the prevalence of metabolic syndrome between menopausal women and women of childbearing age and to determine the risk of metabolic syndrome among women in each group depending on whether they eat alone. Methods: Data of 1,813 women from the seventh Korea National Health and Nutrition Examination Survey (2016) were used. The collected data were analyzed using SPSS 20.0, and complex sample frequency analysis, descriptive statistics, complex sample cross analysis, complex sample general linear regression, and complex sample logistic regression analysis were performed. Results: According to the results of the study, there was no difference in the prevalence and risk of metabolic syndrome according to the presence of companions during meals between women of childbearing age and post-menopausal women, but there was a difference in health behavior. In other words, women of childbearing age who ate alone had a lot of experience of drinking, and menopausal women who ate alone did not tend to make any efforts to control their weight and did not perform aerobic exercise. In particular, the negative health behavior of menopausal women who ate alone increased the risk of prevalence of metabolic syndrome. Conclusion: The findings indicate that, for women who eat alone, interventions to prevent metabolic syndrome should be differentiated before and after menopause. Therefore, it is suggested to offer an educational program to prevent metabolic syndrome in women of childbearing age as well as provide regular assessments to diagnose metabolic syndrome and health behavior improvement programs for menopausal women.

• Journal of the Korean Society of Physical Medicine
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• v.16 no.1
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• pp.103-109
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• 2021

PURPOSE: This study examined the effects of the Visual Analog Scale (VAS) and knee function index on the knee strength and endurance in the national male field-hockey athletes. METHODS: Twenty-four male field-hockey athletes with a painful knee who trained at the national training center in 2019 were enrolled. The VAS and knee function index questionnaire were used to evaluate the degree of pain and functional state of the knee. The muscle strength and endurance of the knee were measured by Biodex (System 4, USA). The Pearson product moment correlation was performed to examine the effects of the VAS and knee function index the of knee on the strength and endurance. In addition, the VAS and knee function index and muscle strength and muscle endurance were examined to determine the relationship using Simple Linear Regression. The statistical significance level was α=.05. RESULTS: An analysis of the correlation between VAS and knee function index and muscle strength and muscle endurance revealed the VAS and knee function index to be statistically significant (r = .700). In addition, the extensor muscle strength, knee VAS (r = -.457), and knee function index (r = -.414) were also statistically significant. A 1-point increase in the VAS and knee function index was associated with an approximately 9.881 and 1.006 extensor muscle strength. CONCLUSION: The VAS and knee function index of field-hockey athletes are related to the strength of the knee extensors. Therefore, field-hockey athletes should develop a program to strengthen the extensor muscle strength of the knee.

• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.102-109
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• 2021

Recently, an interest in risk calculation methods has been increasing in Korea due to the establishment of classification code for explosive hazardous area on gas facility (KGS CODE GC101), which is based on the international standard of classification of areas - explosive gas atmospheres (IEC 60079-10-1). However, experiments to check for leaks of combustible or toxic gases are very difficult. These experiments can lead to fire, explosion, and toxic poisoning. Therefore, even if someone tries to provide a laboratory for this experiment, it is difficult to install a gas leakage equipment. In this study we find out differences among actual experiments, CFD by using FLACS and calculation based on classification code for explosive hazardous area on gas facility (KGS CODE GC101) by comparing to each other. We develpoed KGS HAC (hazardous area classification) program which based on KGS GC101 for convenience and popularization. As a result, actual gas leak, CFD and KGS HAC are showing slightly different results. The results of dispersion of 1.8 to 2.7 m were shown in the actual experiment, and the CFD and KGS HAC showed a linear increase of about 0.4 to 1 m depending on the increase in a flow rate. In the actual experiment, the application of 3/8" tubes and orifice to take into account the momentum drop resulted in an increase in the hazardous distance of about 1.95 m. Comparing three methods was able to identify similarities between real and CFD, and also similarities and limitations of CFD and KGS HAC. We hope these results will provide a good basis for future experiments and risk calculations.

• The Journal of Advanced Prosthodontics
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• v.14 no.2
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• pp.88-95
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• 2022

PURPOSE. This study investigated the accuracy of full-arch intraoral scans obtained by various scan strategies with the segmental scan and merge methods. MATERIALS AND METHODS. Seventy intraoral scans (seven scans per group) were performed using 10 scan strategies that differed in the segmental scan (1, 2, or 3 segments) and the scanning motion (straight, zigzag, or combined). The three-dimensional (3D) geometric accuracy of scan images was evaluated by comparison with a reference image in an image analysis software program, in terms of the arch shape discrepancies. Measurement parameters were the intermolar distance, interpremolar distance, anteroposterior distance, and global surface deviation. One-way analysis of variance and Tukey honestly significance difference post hoc tests were carried out to compare differences among the scan strategy groups (α = .05). RESULTS. The linear discrepancy values of intraoral scans were not different among scan strategies performed with the single scan and segmental scan methods. In general, differences in the scan motion did not show different accuracies, except for the intermolar distance measured under the scan conditions of a 3-segmental scan and zigzag motion. The global surface deviations were not different among all scan strategies. CONCLUSION. The segmental scan and merge methods using two scan parts appear to be reliable as an alternative to the single scan method for full-arch intraoral scans. When three segmental scans are involved, the accuracy of complete arch scan can be negatively affected.