• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.3
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• pp.139-154
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• 1993

The major purpose of this study is to develop a regionalized regression model, which predicts flood peaks from the characteristics of the ungaged catchments, through the regional flood frequency analysis for the selected stage gauging stations located on several natural rivers of Korea. The magnitude and the frequency of flood peaks with specified recurrence intervals were estimated from the flood frequency analysis on the 28 selected stage gauging stations distributed on the five major rivers of Korea. The results of the analysis were compared with the predictions from the two different flood frequency models. From the statistical evaluation of these models, it was revealed that the POT model (Peaks Over a Threshold model), which is based on the partial duration method, is more effective in predicting flood peaks from short period records than the ANNMAX model (ANNual MAXimum model) which is based on the annual maximum series method. A regionalized regression model was developed to facilitate the estimation of design floods for ungaged catchments through the regression analysis between flood peaks and the topographic characteristics of the catchments assumed to be important in runoff processes. In addition to this, the correlation diagrams are presented which show the relationships between flood peaks with specified recurrence intervals and the major characteristics of the catchments.

• International Journal of Internet, Broadcasting and Communication
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• v.9 no.3
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• pp.27-34
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• 2017

According to the material about the analysis of digital consumers' lifestyle in Korea published at the end of 2016, 100% had experienced a smartphone before, and 91% had joined in digital communications. Among digital contents, 85.5% had experienced music, and 78.6% had used TV contents before. Also, SNS utility rate equaled 83.3%, and the Facebook utility rate of those in the 10's and 20's exceeded 80%. It means that it is necessary to conduct research on SNS utility in broadcasts. Based on the results of operating KBS Facebook accounts, this paper aims to compare the reaches of entertainment, drama, and culture genres and analyze correlation between the reaches and 'like' friends on Facebook and also correlation between the reaches and ratings.To address the goal, among the Facebook mentions operated within a year, 2016, this researcher analyzed 2,526 mentions to publicize entertainment, drama, and culture genres and the results of 834 million reaches and also used the data of original broadcasts' ratings. To analyze the data, this study employed SPSS Ver. 18.0 to perform the independent sample t-test and Pearson's correlation analysis. The conference interval is set as 95%, and p<0.05 is regarded to be statistically significant. According to the results, more reaches are found in entertainment, drama, and culture genres in order, and it is found to have strongly positive correlation with the frequency of 'like's. The reaches and ratings have no correlation, and there is no statistical significance found in it. It is expected that the results of this study can be applied to publicize programs efficiently for broadcasting.

• Composites Research
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• v.16 no.2
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• pp.9-17
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• 2003

We have implemented a system of falling weight impact tester in order to evaluate the impact energy absorbing characteristics and impact strength of CFRP laminate plates. The absorbed energy of T-300 orthotropic composites is higher than that of quasi-isotropic specimen over impact energy 7J, but in case of using T700 fiber, much difference does not show. Also, absorbed energy of T-300 orthotropic composites, which are composed of the same stacking number and orientation became more than that of T700 fiber specimen however there was no big difference in case of quasi-isotropic specimens. Delamination area of impacted specimens was measured with ultrasonic C-scanner to find correlation between impact energy and delamination area. Delamination area and frequency responses were evaluated between impacted and unimpacted specimens. There is a strong correlation between frequency responses and impact-induced delamination. The presence and scale of damages have been investigated based on the variations of frequency responses.

• Korean Journal of Child Studies
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• v.20 no.4
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• pp.231-245
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• 1999

The purpose of this study was to examine the relationship between fathers' child-rearing behavior and the competencies of their children and to suggest ways in which fathers can exert a positive influence on their children. The subjects were the fathers and mothers of 649 six- to seven-year-old children attending schools located in T city. Data was analyzed by frequency, percentile, mean, standard deviation, correlation analysis and canonical correlation analysis. Results showed that "limit setting" was the most frequently used child rearing behavior by fathers. On the other hand fathers' "reasoning guidance" was correlated with children's personalities and intellectual competencies.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.7
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• pp.279-286
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• 2002

Linear and nonlinear complex permittivities were measured for copolymers of vinylidene cyanide(VDCN) with vinyl acetate(VAc), vinyl propionate(VPr), vinyl bezoate(VBz), styrene(St) and methyl methacrylate(MMA). Experimental results are well fitted by the function (equation omitted) except at low frequency where dc conduction dominates. The analysis of dielectric relaxation mechanism by combined knowledge about linear and nonlinear dielectric permittivities and dipoles give us informations about electrical and thermal motions in these copolymers. According to the analysis it could be found that the variation for temperature of the dielectric relaxation strength in these copolymers is related to the interaction between dipoles and the nonlinear dielectric effect factor R$_{s}$ is proportional to square of the dipolar correlation factor R$_{p}$././.

• Korean Journal of Human Ecology
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• v.21 no.2
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• pp.241-256
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• 2012

Gas station consumers have become increasingly conscious of expanding choices and service options available at retail outlets. The purpose of this study was to determine key factors in customer choice of gas / service stations. This study seeks to identify key the relationship between socio-demographical variables and consumer choice, and consumer satisfaction and loyalty associated with gas / service station usage. The research instrument comprised of a questionnaire in the form of an on-line survey that was administered during November, 2010. A Total of 1,000 questionnaires were used in the final analysis. The collected data were treated with SPSS Windows 18.0 and analyzed in for frequency, percentage, mean, standard deviation, pearson's correlation analysis, and multiple regression analysis. The results of were as following: First, there was a strong positive relationship between involvement, satisfaction, loyalty of gas station service. Second, satisfaction was significantly affected by involvement, the frequency of gasoline purchases, the information route and customer's occupation. Third, loyalty was significantly affected by consumer satisfaction, involvement, frequency of gasoline purchases, information route and customer's occupation.

• Journal of Preventive Medicine and Public Health
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• v.56 no.5
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• pp.422-430
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• 2023

Objectives: Prolactin is vital for breastfeeding and milk production, and its secretion is influenced by factors related to the mother, infant, and environment. To date, no study has concurrently investigated the correlation of these factors with serum prolactin levels during lactation. Therefore, the objective of this study was to investigate the correlations among maternal and infant factors, lead exposure, and serum prolactin levels during lactation. Methods: A cross-sectional approach was employed in Surabaya, Indonesia, among 110 exclusively lactating mothers. The mothers' daily diets were determined using multiple 24-hour recalls, while blood lead levels were measured with inductively coupled plasma mass spectrometry. Serum prolactin levels were assessed using the electrochemiluminescence immunoassay. For bivariate analysis, we employed the Spearman correlation, Mann-Whitney, and Kruskal-Wallis tests, while for multivariate analysis, we utilized multiple linear regression. Results: The average serum prolactin level of the lactating mothers was 129.19±88.96 ng/mL. Positive correlations were found between serum prolactin levels and breastfeeding frequency (p<0.001), protein intake (p<0.001), and calcium intake (p=0.011) but had negative correlation with blood lead levels (p<0.001) and vitamin B6 intake (p=0.003). Additionally, prolactin levels were not significantly associated with maternal age; parity; intake of calories, vitamin D, vitamin E, zinc, folic acid, magnesium, or iron; infant age; or infant sex. Conclusions: Breastfeeding frequency had a stronger positive relationship with serum prolactin levels than protein and calcium intake. However, lead exposure was associated with reduced serum prolactin levels during lactation. Consequently, specific interventions from policymakers are necessary to manage breastfeeding in mothers exposed to lead.

• The Journal of the Petrological Society of Korea
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• v.26 no.2
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• pp.127-141
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• 2017

Jurassic granite from Geochang was analysed with respect to the characteristics of the rock cleavage. The multicriteria evaluation for the six directions of rock cleavages was performed using the microcrack spacing-related parameters derived from the enlarged photomicrographs (${\times}6.7$) of the thin section and the spacing-cumulative frequency diagrams. The results of analysis for the representative values of these spacing parameters with respect to the rock cleavage are summarized as follows. First, the analysis for deriving the main parameter indicating the order of arrangement among six diagrams was performed. The values of five parameters with respect to six directions of the rock cleavages were arranged in increasing or decreasing order for the above analysis. The decreasing order of the values of main parameter(mean spacing-median spacing, $S_{mean}-S_{median}$) and mean spacing are consistent with the order of H1, H2, G1, G2, R1 and R2 directions. These sequential arrangements of six directions of the rock cleavages can provide a basis for those of the six diagrams related to spacing. Second, the nine correlation charts between the above main parameter and various parameters were arranged in decreasing order of correlation coefficient ($R^2$). These related charts shows a high correlation of power-law function in common. The values of mean spacing, density (${\rho}$) and length of line oa are directly proportional to the value of main parameter, while the values of constant (a), exponent (${\lambda}$), spacing frequency (N), length of line oa', slope of exponential straight line (${\theta}$) and total length ($1mm{\geq}$) are inverse proportional. Third, the results of correlation analysis between the values of parameters for three planes and those for three rock cleavages are as follows. The values of frequency, total spacing, constant, exponent, slope and length of line oa' for three planes and three rock cleavages show an order of R' < G' < H' and H < G < R, respectively. On the other hand, the values of mean spacing, (mean spacing-median spacing), density and length of line oa show an order of H' < G' < R' and R < G < H, respectively. The correlation of the mutually reverse order of the values of parameters between three planes and three rock cleavages can be drawn. This type of correlation analysis is useful for discriminating three quarrying planes.

• Journal of Korean Clinical Nursing Research
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• v.28 no.3
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• pp.299-307
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• 2022

Purpose: The purpose of this study was to understand the effects of infection control fatigue and social support on burnout among nurses during the Coronavirus Disease 2019 (COVID-19) pandemic. Methods: This study is a descriptive survey study designed to confirm the effects of nurses' infection control fatigue and social support on burnout among nurses during the COVID-19 pandemic. The collected data were analyzed using frequency, percentage, mean, standard devia analyzed using frequency, percentage, mean, standard deviation, independent t-test, One-way ANOVA, Scheffe test, Pearson's correlation coefficient, and stepwise multiple regression analysis using SPSS Statistics 26.0. Results: An analysis of the correlations between fatigue from infection control, social support, and burnout showed a positive correlation between burnout and fatigue from infection control (r=.39, p<.001), and a negative correlation between burnout and social support (r=-.29, p<.001). Conflict and lack of support due to uncertain circumstances (β=.51, p<.001), support from supervisor's (β=-.22, p<.001), and experience of infection management education during the previous 1year (β=-.15, p=.007) were identified as the factors that influenced burnout among nurses, and explained 39.0% of the variance in burnout. Conclusion: The results of this study demonstrate that fatigue from infection control and social support influence burnout levels among nurses, which suggests the need to establish a new kind of work culture. Additionally, the findings call for the development and implementation of interventional programs that can reduce fatigue from infection control and increase social support for nurses.

• Journal of the Korean Home Economics Association
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• v.38 no.2
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• pp.109-122
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• 2000

The purpose of this study is to find a mother's influence on her children regarding environmental preservation. The questions of this study are how a mother's background variables influence on their own behaviors, how the children's background variables influences on their own behaviors, how a mother's background variables influence on their children behaviors. This is used self-writing questionaires the 538 subjects are 4th, 5th and 6th grade children and their mothers living in Kwangiu, in June, 1998. The data are analyzed by Frequency, Percentage, Mean, Pearson's correlation, Regression analysis, Path analysis, Coronbach'$\alpha$ coefficent, and Factor analysis. These are the major resets of this study. 1) In case of mothers, the background variables for them to be influenced the environmental presentation behaviors show the frequency of contact for environmental information, average income, family cohesions, the level of communication, egoistic orientation, and age. 2) In Children, the background variables which are influenced on their environmental presentation behaviors represent the frequency of contact for environmental information, family cohesion, biospheric orientation, and the grade level of children. This is, the children who have the more chance of environmental information contact, the higher family cohesion, the higher biospheric orientation, and the lower grade level show the more environmental preservation behaviors. 3) The children who grow seeing their mothers'environmental behaviors such as sorted disposal, recycle behavior, and purchasing behaviors also show the more same behaviors.