• Journal of Korea Water Resources Association
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• v.35 no.2
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• pp.195-201
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• 2002

In this study, an equation is proposed to estimate the limit velocity for lateral stable bed in a curved channel stream. The stable bed on lateral direction is satisfied when there is no more deformation occurs on the transverse bed slope and non-scouring condition in a bend. A theoretical equation for limit velocity is derived using a transverse bed slope model. So, the limit velocity has its theoretical background in the equilibrium of two forces, lateral shear force at the bed due to longitudinal flow and the corresponding lateral bed shear force. To verify the equation, data from four natural river channels were used. There is good agreement between the calculated values using this equation and the measured values. The corrections in equation was found to be correlated with the averaged particle Froude number.

• Korean Journal of Health Education and Promotion
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• v.32 no.1
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• pp.45-55
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• 2015

Objectives: This study is aimed at exploring the temporal developmental relationship of adolescent depression and parents' child-rearing attitudes, and to examine gender differences in the relationship. The middle school students of the 2011-2013 1st Korea Children and Youth Panel data were used for analysis and the sample consisted of 2.073 individuals. Methods: Research questions were answered through the Latent Growth Model and Autoregressive Cross-Lagged Model. Results: As the results of the Latent Growth Model show, adolescent depression declines as time goes by and there are differences in the depression felt by individuals. An autoregressive cross-lagged model and multiple group analysis were executed by gender. The results show significant gender differences in the relationship between depression and Parents' child-rearing attitudes. Parental neglect has shown differences influencing adolescents depression between males and females. However, in case of parental abuse, no differences between males and females were observed. Conclusion: The results of this study imply that the policy on depression should be carefully considered when preparing for interventions targeting adolescents by gender.

• Research in Community and Public Health Nursing
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• v.16 no.1
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• pp.32-39
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• 2005

Purpose: this study was to verify the effects of the smoking prevention education as an intervention to prevent smoking among male middle school students. Method: this study was designed using one group pre-post test. The subjects were 169 male middle school students living in Jecheon city. The instruments used in this study were scales on smoking cessation intention and knowledge and attitude toward smoking. Students received 8 sessions of smoking prevention education for 45 minutes every week. from April to July 2003. The data was analyzed by descriptive statistics and paired t-test using the SPSS Win 8.0 program. Results: after the completion of the smoking prevention education, the smoking cessation intention(t=.37, p=.705)was not increased significantly but the knowledge(t=-3.84. p=.000) and attitude(t=-3.16, p=.002) on smoking were increased significantly. Conclusion: the smoking prevention education for male middle school students increased their knowledge on smoking and student's attitude to smoking turned more negatively. Further study on longitudinal effect using Pre-test/ Post-test control group design are also recommended.

• Journal of Korean Foot and Ankle Society
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• v.17 no.4
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• pp.309-315
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• 2013

Purpose: The purpose of the study was to investigate five cases with chronic Achilles tendon rupture that occurred after steroid injections. Materials and Methods: In our hospital, we experienced five cases of chronic Achilles tendon rupture from September 2010 to March 2012. All patients had got steroid injection for Achilles tendinitis at the other hospitals, and their heel pain was aggravated when they visited our outpatient department. After treatment, signs and symptoms of Achilles tendon rupture were developed and the diagnosis was confirmed by ultrasonography or magnetic resonance imaging (MRI). Surgical treatment was done for Achilles tendon rupture. Results: There was difference between intra-operative findings of Achilles tendon rupture and usual chronic Achilles tendon rupture. Unlike usual findings of chronic Achilles tendon rupture whose scar tissue or tissue attenuation are found around the defect area of Achilles tendon, there were partial necrosis of tendon severe adhesion with surrounding tissue, extensive defect and longitudinal rupture on ruptured area. Also, severe inflammation of paratenon, granulation and fibrinoid deposit were found on biopsy findings in four cases. Conclusion: Based on review of data about relative risk and benefit of local corticosteroid injection to inflammatory lesion in Achilles tendon, it requires more attention to Achilles tendon rupture following local corticosteroid injection.

• Journal of Family Resource Management and Policy Review
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• v.15 no.4
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• pp.65-78
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• 2011

The purpose of this study was to examine the experience of retirement and how life satisfaction after retirement differs depending on the individual, family, and social characteristics of middle-aged and elderly Korean men and the experience of retirement. Data were drawn from the first wave of the Korean Longitudinal Study of Ageing (KLoSA). The sample consisted of 278 retired middle-aged and elderly Korean men aged between 45 and 64. The results showed that middle-aged and elderly Korean retirees' reasons for retirement differed depending on their health satisfaction. In addition, their retirement satisfaction varied according to their education, health satisfaction, economic satisfaction, and reasons for retirement. Regarding their life satisfaction, it was predicted by their age and satisfaction with health status, economic situation, marriage, and relationship with their children.

• Journal of the Korean Home Economics Association
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• v.34 no.3
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• pp.75-87
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• 1996

The purpose of the study was to examine the effect of sex role orientation on the amount of time spent in meal preparation and cleanup, clothing care, and indoor cleaning accomplished by husbands and wives in couple-headed households in the U.S.. The overall research hypotheses examined were : (1) there is a relationship between demographic and socioeconomic characteristics of the husband and wife and the sex role orientation of the husband and wife; (2) for both husbands and wives, there is a relationship between sex role orientation and the amount of household production time that is accomplised by each individual; and (3) the relationship between sex role orientation and the amount of household production time remains when demographic and socioeconomic factors are controlled. The 1981 data from the 1975-1981 Time Use Longitudinal Panel Study collected at the University of Michigan were used for this study. The major findings is that a relationship between sex role orientation and the amount of time spent in three household production activities was not found, when all independent variables were controlled. That is, sex activities was not found, when all independent variables were controlled. That is, sex role orientation was not a predictor affecting the amount of time that husbands and wives spend on meal preparation and cleanup, clothing care, and indoor cleaning.

• Electrical & Electronic Materials
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• v.8 no.6
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• pp.685-692
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• 1995

The electron transport coefficients in argon gas is studied over the range of E/N values from 85 to 566 Td by the Monte Carlo method considering the latest cross section data. The result of the Monte Carlo method analysis shows that the value of the electron transport coefficients such as the electron drift velocity, the ratio of the longitudinal and transverse diffusion coefficients to the mobility. It is also found that the electron transport coefficients calculated by the two-term approximation analysis agree well with those by Monte Carlo calculation. The electron energy distributions function were analysed in argon at E/N=283, and 566 Td for a case of the equilibrium region in the mean electron energy. A momentum transfer cross section for the argon atom which was consistent with both of the present electron transport coefficients was derived over the range of mean electron energy from 10.3 to 14.5 eV, also suggested as a set of electron cross section for argon atom. The validity of the results obtained has been confirmed by a Monte Carlo simulation method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.1
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• pp.62-67
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• 2016

In this paper, the IES file was measured by applying a secondary optical lens to a 21 W LED engine, and the lighting calculation software RELUX was used to perform simulations with the data file of this measurement. For two-lane (two way) concrete paved roads, six LED engine are applied to each streetlight and simulation results show that Uo (uniformity) 0.56, UI (longitudinal uniformity) 0.86 and TI (threshold iIncrement) 9% which satisfies the required standards. RELUX was also used to LED streetlights by designing them in three dimensions, that is ${\pm}25%$ of the arm length of 2.8 m standardized by the road lighting standards of the Korea Expressway Corporation. Comparative analysis was carried out on adjustments were made in increments of 0.1 m that Uo, UI, and TI values in the range of arm lengths from 2.1 m~3.5 m. For the arm length range of 2.1 m~2.4 m, Uo was high, whereas UI was low. Therefore, we present the optimal light distribution values designed for an arm length of 2.5 m.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.53 no.2
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• pp.65-69
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• 2004

This paper calculates and gives the analysis of electron swarm transport coefficients as described electric conductive characteristics of pure Ar, pure $SiH_4$, Ar-$SiH_4$ mixture gases($SiH_4$-0.5%, 2.5%, 5%) over the range of E/N = 0.01~300[Td], P = 0.1, 1, 5.0 [Torr] by Monte Carlo the backward prolongation method of the Boltzmann equation using computer simulation without using expensive equipment. The results have been obtained by using the electron collision cross sections by TOF, PT, SST sampling, compared with the experimental data determined by the other author. It also proved the reliability of the electron collision cross sections and shows the practical values of computer simulation. Electron swann parameters in argon were drastically changed by adding a small amount of mono-silane. The electron drift velocity in these mixtures showed unusual behaviour against E/N. It had negative slope in the medium range of E/N, yet the slope was not smooth but contained a small hump. The longitudinal diffusion coefficient also showed a corresponding feature in its dependence on E/N. A two-tenn approximation of the Boltzmann equation analysis and Monte Carlo simulation have been used to study electron transport coefficients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5558-5563
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• 2011

Using longitudinal data of 108 firms in large business conglomerates from 2001 to 2009, this study examines the impact of controlling shareholders' control-ownership disparity on R&D investment. The study finds that control-ownership disparity is negatively related to R&D intensity. This empirical result suggests that controlling shareholders' control rights in excess of ownership rights incent controlling shareholders' expropriation for their private interests, leading to decreased R&D investment which enhances firm value in the long term.