• Journal of Korean Society on Water Environment
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• v.28 no.4
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• pp.538-550
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• 2012

This study suggests a general methodology which is designed for assessing RDOC behavior at the catchment scale by coupling properly a series of steam flow and water quality simulation models and actual monitoring data set. The modified TANK model in which a river routing function is incorporated to the conventional one is applied to simulate the long-term daily stream flow data, and the simulated stream flow data is combined with the 7-parameter log-linear model coupled to the minimum variance unbiased estimator to simulate the long-term daily water quality (BOD, COD and TOC) loads. Finally, the regression analysis between the usually monitored water quality data (BOD, COD and TOC) and RDOC is combined with the simulated water quality data to manifest the spatio-temporal variability of RDOC flux behavior at the Korean TMDL catchment scale.

• Structural Engineering and Mechanics
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• v.63 no.1
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• pp.37-46
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• 2017

This paper is concerned with the numerical study on the resonance response of a rigid spar-type floating platform in coupled heave and pitch motion. Spar-type floating platforms, widely used for supporting the offshore structures, offer an economic advantage but those exhibit the dynamically high sensitivity to external excitations due to their shape at the same time. Hence, the investigation of their dynamic responses, particularly at resonance, is prerequisite for the design of spar-type floating platforms which secure the dynamic stability. Spar-type floating platform in 2-D surface wave is assumed to be a rigid body having 2-DOFs, and its coupled dynamic equations are analytically derived using the geometric and kinematic relations. The motion-variance of the metacentric height and the moment of inertia of floating platform are taken into consideration, and the hydrodynamic interaction between the wave and platform motions is reflected into the hydrodynamic force and moment and the frequency-dependent added masses. The coupled nonlinear equations governing the heave and pitch motions are solved by the RK4 method, and the frequency responses are obtained by the digital Fourier transform. Through the numerical experiments to the wave frequency, the resonance responses and the coupling in resonance between heave and pitch motions are investigated in time and frequency domains.

• Journal of Families and Better Life
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• v.24 no.2 s.80
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• pp.149-163
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• 2006

The purposes of this study were to explore ecological variables that affect family functions and to analyze relative magnitudes of significant predictors. The study employed ecological model. Data were collected from 143 mothers of mildly handicapped children enrolled in integrated kindergartens in Seoul, Korea. The results of the study were as follows : 1. The level of family functions with mildly handicapped children were found to be moderate(M=3.21, SD=.49). 2. The hierarchical regression analysis yielded Model V as the most powerful model, explaining 79%$(Adjusted\;R^2=.787)$ of the variance. 3. The most powerful predictors throughout Model I to V were found to be maternal efficacy $({\beta}=.578,\;p<.001)$, maternal satisfaction with parent-education and counseling programs $({\beta}=.249,\;p<.001)$, husband's helps $({\beta}=.207,\;p<.01)$, and the availability of assistance other than family members $({\beta}=.232,\;p<.05)$ in the order.

• Journal of The Korean Digital Architecture Interior Association
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• v.11 no.2
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• pp.41-50
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• 2011

Skeptical responses to urban design based on the Physical Planning theory assuming the existence of social agreement and the absolute authorities of planners bring about alternatives such as Participatory Planning and Community Design derived from Harbermas' Communicative Rationality. But the normative contentions do not progress any more to the stage of presenting practical strategies. This is the cause why there should be systematic approaches to reveal the relationships among various concepts or variables. With regard to the Community Design this study intends to take a statistical approach to find relationship between project scale and its accomplishment. The hypothesis that the smaller scale of project begets the better outcomes was tested to be rejected as a result of the analysis of variance. But the result also shows that appropriate density in relatively large area makes residents' expected satisfaction high. Although this discovery has its own meaning the tryout is anticipated to laying the cornerstone of quantitative analyses in the following studies.

• Journal of East-West Nursing Research
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• v.18 no.2
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• pp.104-110
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• 2012

Purpose: The purpose of this study was to investigate the relationship between health promotion behavior and aggression among teenagers. Methods: This was a descriptive study. The survey participants were 502 teenagers. Data was collected from September 7 to October 5, 2009. The data was analyzed using descriptive analysis, independent-samples t-test, ANOVA, and stepwise multiple regression. Results: The average age of participants was 14.4. Fourty eight percent of participants were male, 67.3% were middle-class house, 23.1% were above overweight, 6.3% were daily smoker, 43.5% were occasional drinker. Age was found to have a statistically negative correlation with health promotion behavior, while having positive correlation with aggression. There were significant differences in teenagers' health promotion behavior and aggression according to their smoking and drinking experiences. Personal regression was identified as the most powerful predictor of teenager's aggression. Personal relationship, nutrition accounted for 15.7% of the variance. Conclusion: It is necessary to consider a program related to teenager's health promotion for reduction of their aggression level.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1248-1253
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• 2003

Sensitivity information has been used for linearization of nonlinear functions in optimization. Basically, sensitivity is a derivative of a function with respect to a design variable. Design sensitivity is repeatedly calculated in optimization. Since sensitivity calculation is extremely expensive, there are studies to directly use the sensitivity in the design process. When a small design change is required, an engineer makes design changes by considering the sensitivity information. Generally, the current process is performed one-by-one for design variables. Methods to exploit the sensitivity information are developed. When a designer wants to change multiple variables with some relationship, the directional derivative can be utilized. In this case, the first derivative can be calculated. Only small design changes can be made from the first derivatives. Orthogonal arrays can be used for moderate changes of multiple variables. Analysis of Variance is carried out to find out the regional influence of variables. A flow is developed for efficient use of the methods. The sensitivity information is calculated by finite difference method. Various examples are solved to evaluate the proposed algorithm.

• Journal of Environmental Health Sciences
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• v.40 no.6
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• pp.477-483
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• 2014

Objectives: This study was carried out to investigate the characteristics of odors emitted from sewage in a sanitary sewer and its outlets. Methods: The concentration of mal-odorous sulfur was analyzed by gas chromatograph, and odor intensity was estimated by an on-site sensory test. Odor intensity calculated from instrumental analysis results was compared with odor intensity observed at field. Results: As a results, the concentration of $H_2S$ ranged from 2.4 ppb to 5,889 ppb (average 703 ppb), while $CH_3SH$, $(CH_3)_2S$, and $(CH_3)_2S_2$ showed from 10 ppb to 554 ppb (average 119 ppb) and from 20 ppb to 332 ppb (average 70 ppb) and from 2.7 ppb to 8.1 ppb (average 5 ppb) individually. Average odor intensity observed in the field was degree three. Odor intensity calculated from sulfur compound concentration was confirmed as similar to the observed odor intensity because the coefficient of variance between the observed and the calculated intensities was less than one. Conclusion: It was expected that the results of this study will be helpful to design a deodorizing device to reduce odor emissions from sewerage facilities in the future.

• Journal of Families and Better Life
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• v.3 no.1
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• pp.107-125
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• 1985

This paper investigated adult's consciousness with a view to establishing basic data about set-up any concrete plan and provision for elderly life in hoe and society. In this paper, the study of concerned reference and social survey by questionnaire are used. The data is obtained from 326 espondents who are 30 to 4 years old in Seoul and Andong. As to consciousness to the provision for elderly life and situation of set-up any concrete plan, the x2(chi-square) is applied to the analysis of regional, socio-economical, demographic difference. The conclusion of this study are as follows; 1) Although the respondents show positive attitude toward consciousness to the provision for elderly. life, their behavior does not show any sing of translating it into reality. 2) The consciousness to the provision for elderly life varies according to regional, socio-economical, demographic variance. Those who are in their 30's more-educated, and high-income want to be more independent from their children and express strong desire to set-up provision for elderly life in advance. This is also true of those living in city. As a results, as adults(30-54) recognize the importance of provision for elderly life, so the support by the society or governmental policy for the solution of better-life for old people is important. however, mental , physical, economical preparation in family life according to the family life cycle can basic solution.

• Journal of Families and Better Life
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• v.30 no.3
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• pp.45-57
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• 2012

The purpose of this study was to investigate the structural relationships among different variables related to well-being. 748 elementary school students residing in Gumi-City, Pohang-City and Ulsan-City in Korea completed questionnaires about well-being, ego-resilience, self-esteem, basic psychological needs and parent attachment perceived by children. A variance-covariance matrix of this sample was analyzed using AMOS 19.0, and the maximum likelihood minimization function. The goodness of fit was evaluated via SRMR, RMSEA with a 90% confidence interval, CFI, and TLI. The results were as follows: First, children's ego-resilience, self-esteem, basic psychological needs and parent attachment were all found to have a significant direct effect on children's well-being. Second, children's self-esteem, basic psychological needs and parent attachment had a direct effect on children's ego-resilience. Third, children's basic psychological needs and parent attachment had a direct effect on children's self-esteem. Fourth, parent attachment had a direct effect on children's basic psychological needs.

• Journal of the Korean Home Economics Association
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• v.42 no.12 s.202
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• pp.219-230
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• 2004

The purpose of this study was to investigate relationships between the family strengths, mothers' self-efficacy, and their young children's teaming-related social skills and behavior problems. The subjects were the 217 children aged 4 to 6 years and their mothers at private child care centers in Seoul. The Family Strengths Scale and the Mothers' Self-Efficacy questionnaire were administered to the mothers. The teachers rated the learning-related social skills and problem behaviors of each child whose mother returned a set of Questionnaires. Analysis of variance revealed statistically significant differences in the family strengths according to the education level of the mothers. The mean the family strength score was higher for working mothers than for non-working mothers. The results of the test were statistically significant differences in the scores on the learning-related social skills and problem behaviors between boys and girls. The family strengths were positively correlated with the mothers' self-efficacy, and the learning-related social skills of the young children, while they were negatively correlated with problem behaviors.