• Corrosion Science and Technology
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• v.21 no.5
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• pp.360-371
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• 2022

Electropolishing has various parameters because an electrochemical reaction is applied. Accordingly, experiments to determine factors and levels of electropolishing conditions are in progress for various materials. The purpose of this investigation was to optimize conditions for electropolishing using the taguchi method for UNS S31603. Factors such as electrolyte composition ratio, electrolyte temperature, and electropolishing process time were selected. Electropolishing was optimized using analysis of variance (ANOVA), signal-to-noise ratio (the smaller the better characteristics), and surface analysis. Results of ANOVA revealed that only the electrolyte composition ratio among factors was effective for surface roughness. As a result of statistical analysis of the signal-to-noise ratio, the highest signal-to-noise ratio was calculated under electropolishing conditions with sulfuric acid and phosphoric acid ratio of 4:6, an electrolyte temperature of 75 ℃, and electropolishing process time of 7 minutes. In addition, the surface roughness after electropolishing under the above conditions was 0.121 ㎛, which was improved by more than 88% compared to mechanical polishing.

• Journal of the Korean Home Economics Association
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• v.39 no.9
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• pp.95-102
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• 2001

The Effects of Self-Esteem and Sociocultural Attitude toward Appearance on Clothing Behavior. The purpose of this study was to investigate to relation between self-esteem and sociocultural attitude toward appearance and clothing behavior i.e. individuality/self expression, body improvement, social approval, sex appeal. Measurements were included Rosenberg's self-esteem, Thompson's sociocultural attitude toward appearance questionnaire and clothing behavior. The data were collected from 498 female university students in Seoul and Kyongki Province. The collection works were undertaken between the 15th of June and 30th of June, 2001, The data were analyzed using factor analysis, reliability test, analysis of variance, and multiple regression analysis. The results of this study were as follows : 1) Three dimensions of sociocultural attitude toward appearance were identified: internalization, social awareness, and concrete awareness. 2) Self-esteem and internalization of sociocultural attitude toward appearance had an effect on clothing behavior i.e. individuality/self expression, body improvement, social approval and sex appeal. Social awareness of sociocultural attitude toward appearance had an effect on body improvement, social approval, and sex appeal.

• Journal of the Korean Society of School Health
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• v.21 no.2
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• pp.23-33
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• 2008

Purpose: Internet is one of the essential tools in South Korean adolescent life. Recently, researchers suggest that Internet use is positively associated with teens' mental health problems such as depression and suicide. Thus, this study explored a relationship between Internet use and suicide ideation among South Korean adolescents. Methods:　Secondary data, the three-wave Korean Youth Panel Survey, were analyzed. First, in terms of the levels of Internet use and suicidal ideation, t-test was used for examining a gender difference, and Analysis of Variance were used for examining differences across three points in time(waves 2 - 4). Second, logistic analysis was performed to examine the significant association between Internet use and suicide ideation after controlling for the other factors' effects. In this analysis, Fixed Effect Regression Method(FERM) was incorporated as well. FERM was useful in adjusting for the effects of time-invariant factors even without measuring them. As a result, it was possible to obtain more accurate findings. Results: Adolescent depression was an important factor influencing the association between Internet use and suicide ideation. After controlling for the effect of depression, the relationship between Internet use and suicide ideation was no longer statistically significant. Conclusion:　As a proxy to identify teens who are obsessed with suicide ideation, levels of Internet use do not seem useful. Instead, it is necessary to examine teens' access to websites related to suicide.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.9
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• pp.963-968
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• 2009

This paper deals with shrink fit analysis of rotor by 2D cross-section, 2D axis-symmetry, and 3D FEM model. And this paper presents 2nd order approximation function of thermal expansion displacement by design variables (shape dimension, heating temperature, sleeve length, interference etc.), table of orthogonal array and RSM(response surface methodology). The possibility of the rotor with shrink fit is evaluated by thermal expansion displacement. If thermal expansion displacement is larger than interference, shrink fit enable to make the rotor. 2D axis-symmetry model and 3D model are more reasonable than 2D cross-section model, because stress and strain is different along length of shaft.

• The Korean Journal of Health Service Management
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• v.6 no.1
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• pp.173-183
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• 2012

This study is designed to look into the relations between college students' will for the improvement of their health and self-efficacy, happiness, life satisfaction and leisure satisfaction. To achieve this, a survey was carried out from November 2011 to December 2011, targeting 876 college students in 10 different regions in Busan and Gyeongsangnam-do area. From the questionnaires, undependable and inappropriate questionnaires were excluded and 812 questionnaires were used for analysis data in descriptive statistics, variance analysis and simple regression analysis. The results are as follows. The groups with the strong show higher self-efficacy, have more happiness and express better life satisfaction. It has been empirically proved that those college students with a strong will to improve their health love themselves more and value themselves higher, which has positive influences on their happiness, life satisfaction and leisure satisfaction.

• Journal of Families and Better Life
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• v.28 no.2
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• pp.51-62
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• 2010

This study aims to find out how childhood teachers recognize the characteristic of children, family and community resilience and there are any relationships between children, family and community resilience that teachers recognize. In this Study, 280 teachers working in kindergarten and nurseries in Busan and Ulsan Metropolitan City were subjected to questionnaire survey. Data obtained were analyzed by using frequency, percentage, average, standard deviation, one-way analysis of variance, correlation analysis and factor analysis of SPSS 12.0 statistical program. The results were as follow: First, childhood teacher recognized optimism and positiveness as characteristics of childhood resilience. Second, childhood teacher recognized family cohesion and role stability as characteristics of family resilience. Third, childhood teacher recognized community service and support system as community resilience. Fourth, childhood teacher recognized illustrates mutually organic relationship amongst them, childhood resilience was found to be more closely related to family resilience.

• YAKHAK HOEJI
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• v.44 no.4
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• pp.308-314
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• 2000

Logarithmic transformation of pharmacokinetic parameters is routinely used in bioequivalence studies based on pharmacokinetic and statistical grounds by the United States Food and Drug Administration (FDA), European Committee for Proprietary Medicinal Products (CPMP), and Japanese National Institute of Health and Science (NIHS). Although it has not yet been recommended by the Korea Food and Drug Administration (KFDA), its use is becoming increasingly necessary in order to harmonize with international standards. In the present study, statistical procedures for the analysis of a bioequivalence based on the log transformation and a related SAS procedure were demonstrated in order to aid the understanding and application. The AUC parameters used in this demonstration were taken from the previous bioequivalence study for two aceclofenac tablets, which were performed in a single-dose crossover design. Analysis of variance (ANOVA), statistical power to detect 20% difference between the tablets, minimum detectable difference and confidence intervals were all assessed following log-transformation of the data. Bioequivalence of two aceclofenac tablets was then estimated based on the guideline of FDA. Considering the international effort for harmaonization of guidelines for bioequivalence tests, this approach may require a further evaluation for a future adaptation in the Korea Guidelines of Bioequivalence Tests (KGBT).

• Journal of the Korean Institute of Navigation
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• v.20 no.4
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• pp.7-44
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• 1996

The purpose of this study is to develop the training programme for VTS operators in Korea. The methodology used are literature and questionnaire survey. The literature, proceedings of international symposia and letters from Canada, USA, Japan and other countries were properly used and analyzed in order to compare their contents. Through the results of this study, I proposed the basic training programme for VTS operators in Korea as followings. First, the number and level of Korean VTS should be properly decided. Second, the training organization and staff should be built and appointed. Third, the VTS trainee should selected, and the training level & period should be established according to their qualification and experience. Fourth, the training should be acted by the VTS training curriculum. Fifth, The VTS operator certificate should be issued through proper test. This paper concluded as followings through the analysis of the questionnaire regarding to VTS training programme in Korea. First, the proposed curriculum were properly constructed and the independence among them was existed through the reliability and correlation analysis. Second, the difference of the curriculum importance among the questionnaire group was nearly not found through the Analysis of Variance(ANOVA). Third, the required days per each curriculum was limited to maximum 5days.

• Journal of Korean Public Health Nursing
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• v.35 no.1
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• pp.120-134
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• 2021

Purpose: The reproductive health of women in early adulthood can affect pregnancy, childbirth, and menopause in later life. Menstrual symptoms not only affect daily life, but are also a reflection of a woman's reproductive health. This study was conducted to explore the factors affecting menstrual symptoms among university students. Methods: The general characteristics, life style, menstrual characteristics, stress, and menstrual symptom of 177 female students were assessed through an online survey at one university. An independent sample t-test, one-way variance analysis, correlation analysis, and multiple regression analysis were performed using the SPSS 22.0 program. Results: The menstrual symptom score was 91.68±32.11 points, and the score of 'mood change' was the highest. Stress (��=.38, p<.001), amount of menstruation (��=.20, p=.001), menarche age (��=-.18, p=.003), health problems (��=.16, p=.010), and age (��=.15, p=.016) were found to have a significant effect on menstrual symptom, and the explanatory power of the regression model was 40%. Conclusion: This study investigated the degree and influencing factors of menstrual symptom using the Korean Menstrual Symptom Scale (KMSS) developed for Korean university students. Among the factors influencing menstrual symptom, stress appeared to play a significant role. Stress management, observation of menstrual characteristics, and general health care are necessary to maintain a woman's reproductive health.

• Journal of Climate Change Research
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• v.7 no.4
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• pp.407-419
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• 2016

The low flow is the necessary and important index to establish national water planning, however there are lots of uncertainty in the low flow estimation. Therefore, the objectives of this study are to assess the climate change uncertainty and the effects of hydrological models on low flow estimation. The 5 RCMs (HadGEM3-RA, RegCM4, MM5, WRF, and RSM), 5 statistical post-processing methods and 2 hydrological models were applied for evaluation. The study area were selected as Chungju dam and Soyang river dam basin, and the 30 days minimum flow is used for the low flow evaluation. The results of the uncertainty analysis showed that the hydrological model was the largest source of uncertainty about 41.5% in the low flow projection. The uncertainty of hydrological model is higher than the other steps (RCM, statistical post-processing). Also, VIC model is more sensitive for climate change compared to SWAT model. Therefore, the hydrological model should be thoroughly reviewed for the climate change impact assessment on low flow.