• The Journal of Korean Association of Computer Education
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• v.19 no.1
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• pp.87-100
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• 2016

This study has examined the structural relationship among factors related to the effects of flipped learning using the structural equation modeling. Two hundred thirty-six middle school and high school students were participated in this study. This study's results are as follows. First, looking through how much the flipped learning variables affect achievement, motivation affects achievement the most, and then interaction, participation come next. Second, looking through how much the flipped learning variables affect personality, interaction affect personality the most, and then teaching attitudes come next. Third, as a result of verifying the research model, the hypothetical model indicating relationship among motivation, participation, teaching attitudes, interaction and achievement, personality is valid.

• Nuclear Engineering and Technology
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• v.24 no.3
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• pp.274-284
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• 1992

A 1/15-scale CREARE experiment, which simulates the thermal-hydraulic behavior in the reactor pressure vessel of a PWR during a hypothetical Loss Of Coolant Accident, has been analyzed using CATHARE code for the associated model assessment to represent the phenomenon. The key parameters examined in the CREARE experiment were known as ECC water injection rate. ECC water subcooling, system pressure, and steam flow rate coming out from the core bottom. The present CATHARE simulation, however, has been mainly focused on qualitative analysis of a countercurrent flow in the downcomer. The discrepancy of the simulation results with the experimental data is considered arising primarily from an inadequate numerical representation as well as an interfacial friction model. Accordingly it is suggested from the sensitivity studies that either multidimensional approach or further examination of momentum equations at a junction near a volume element in CATHARE be necessary in order to represent the phenomenon more realistically.

• Journal of Korean Academy of Nursing
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• v.46 no.1
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• pp.118-127
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• 2016

Purpose: The study purposes were to construct and test structural equation modeling on the causal relationship of community residents' perceived quality of care, image, and role performance with satisfaction, intention to (re)visit and intention to recommend hospital. Methods: A cross-sectional survey was conducted with 3,900 community residents from 39 district public hospitals. The questionnaire was designed to collected information on personal characteristics and community awareness of public hospitals. Community awareness consisted of 6 factors and 18 items. The data were collected utilizing call-interview by a survey company. Research data were collected via questionnaires and analyzed using SPSS version 20.0 and AMOS version 20.0. Results: Model fit indices for the hypothetical model were suitable for the recommended level: ${\chi}^2=796.40$ (df=79, p<.001), GFI=.93, AGFI=.90, RMSR=.08, NFI=.94. Quality of care, image, and role performance explained 68.1% of variance in community awareness. Total effect of quality of care process factors on satisfaction (path coefficients=3.67), intention to (re)visit (path coefficients=2.67) and intention to recommend hospital (coefficients=2.45) were higher than other factors. Conclusion: Findings show that public hospitals have to make an effort to improve community image through the provision of quality care, and excellent role performance. Support for these activities is available from both Central and Local Governments.

• Journal of Korean Academy of Nursing
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• v.47 no.5
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• pp.624-637
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• 2017

Purpose: This study aimed to identify variables influencing the health-related quality of life (HRQoL) of adults with epilepsy in order to establish a structural model and design an intervention strategy to improve patients' HRQoL. Methods: The selected subjects were 212 patients with epilepsy aged between 18 and 70 years who were currently receiving treatment from hospital, general hospital, and clinic. They were surveyed using a structured questionnaire. Results: The goodness of fit measures of the final hypothetical model were as follows: ${\chi}^2/df=2.51$, GFI=.91, AGFI=.90, CFI=.96, SRMR=.04, NFI=.93, and RMSEA=.08. The major variables influencing the HRQoL of adults with epilepsy were epilepsy self-efficacy, depression, social support, and side effects of anti-epileptic drugs (AEDs), which were significant in the mentioned order, whereas the duration of AEDs use and perceived stigma did not show any effects. Six variables accounted for 75.6% of HRQoL. Variables having a direct and total effect on the HRQoL of adults with epilepsy were the side effects of AEDs, social support, epilepsy self-efficacy, and depression, and those with an indirect effect were the side effects of AEDs and social support. Conclusion: It is necessary to accurately identify the side effects of AEDs in adults with epilepsy and accurately observe the physical changes caused by depression. In addition, it is imperative to establish an active and effective nursing intervention program to strengthen the self-efficacy of the patients and to improve their quality of life through social support provided by family members and medical professionals.

• Journal of Families and Better Life
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• v.24 no.6 s.84
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• pp.95-116
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• 2006

The purpose of this study was to validate a hypothetical path model of maternal childhood attachment, emotions, parenting behaviors, and child behavioral problems. The research was conducted with 240 sets or mothers and their children 70 mother-child teams from seven counseling organizations including the Children's Counseling Clinic, Community Social Welfare Service Center, and Welfare Service Center for the Disabled in Seoul, Incheon, and Pyeongtaek, and 170 elementary school children from Seoul and their mothers. Consequently, a total of 200 mother-child teams were selected for this study. The data in this study were analyzed with SPSS 12.0 program and LISREL 8.3 program. The result of this study is as follows: (1) Examining the path of paternal attachment and the internalizing and externalizing behavioral problems, it was noted that paternal attachment had the indirect effect of anxiety and over-protection on the path to internalizing problems and the indirect effect of anxiety also noted is that there is a full-mediation of anxiety and over-protection between paternal attachment and the internalizing problems. (2) Examining the path of maternal attachment and the internalizing problems, it was noted that maternal attachment has direct effect on the internalizing problems. Maternal attachment has the indirect effect of self-esteem depression, anxiety and over-protection on the Path, and the indirect effect of self-esteem, anxiety and over-protection. (3) Examining the path of maternal attachment and the externalizing problems, it was noted that maternal attachment has direct effect on the externalizing problems and on the path to the externalizing problems, and maternal attachment has the indirect effect of depression, the indirect effect of self-esteem and authoritarian control, and the indirect effect of self-esteem and depression.

• Human Ecology Research
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• v.59 no.2
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• pp.233-243
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• 2021

This study examined the longitudinal effects of media usage by early school-age children and of maternal parenting stress on children's school adjustment. The study focused on the mediating effect of executive function difficulty. Longitudinal data to examine the hypothetical model were drawn from the eighth (2015) through tenth (2017) waves of the Panel Study of Korean Children (PSKC) collected by the Korea Institute of Child Care and Education (KICCE). A total of 581 children (293 boys and 288 girls) and their mothers were included. Confirmatory factor analysis, structural equation model, and bootstrapping analysis were applied using SPSS 25.0 and Amos 26.0. The results are as follows. First, no significant correlation was found between early school-age children's media usage and maternal parenting stress. Second, neither media usage by early school-age children nor maternal parenting stress were found to directly affect children's school adjustment. Third, media usage by early school-age children and maternal parenting stress were shown to indirectly affect children's school adjustment via executive function difficulties. In other words, higher levels of media usage by early school-age children and maternal parenting stress during the first grade lead to greater executive function difficulties after a year, which, in turn, lead to a lower level of school adjustment in the third grade. This study indicates the need to develop practical support for the psychological wellbeing of mothers while they are performing their role as a parent and for children in maintaining suitable levels of media usage during early childhood.

• Journal of Astronomy and Space Sciences
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• v.39 no.1
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• pp.1-10
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• 2022

The universe is thought to be filled with not only Standard Model (SM) matters but also dark matters. Dark matter is thought to play a major role in its construction. However, the identity of dark matter is as yet unknown, with various search methods from astrophysical observartion to particle collider experiments. Because of the cross-section that is a thousand times smaller than SM particles, dark matter research requires a large amount of data processing. Therefore, optimization and parallelization in High Performance Computing is required. Dark matter in hypothetical hidden sector is though to be connected to dark photons which carries forces similar to photons in electromagnetism. In the recent analysis, it was studied using the decays of a dark photon at collider experiments. Based on this, we studies double dark photon decays at lepton colliders. The signal channels are e⁺e^- → A'A' and e⁺e^- → A'A'γ where dark photon A' decays dimuon. These signal channels are based on the theory that dark photons only decay into heavily charged leptons, which can explain the muon magnetic momentum anomaly. We scanned the cross-section according to the dark photon mass in experiments. MadGraph5 was used to generate events based on a simplified model. Additionally, to get the maximum expected number of events for the double dark photon channel, the detector efficiency for several center of mass (CM) energy were studied using Delphes and MadAnalysis5 for performance comparison. The results of this study will contribute to the search for double dark photon channels at lepton colliders.

• Korean Journal of Social Welfare
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• v.51
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• pp.29-61
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• 2002

This study was designed to find out the determinants of types of bullying behavior, and the effects of types of bullying behavior on the bullies. For this purpose, a hypothetical model which explains the relationships among 6 environmental factors, 5 types of bullying behavior, and 5 outcome variables for the bullies was developed. Using the data collected from 177 junior and high school students who have bullied the other students, the hypothetical model was tested. For data analysis, a path analysis was used, and the best-fitting model was found (df=78, GFI=0.953, CFI=1.00). As a result of analyzing the model, types of bullying behavior were found to be determined by the different environmental factors: Isolation was determined by 2 factors (feeling of isolation from friends, exposure to bullying), social bullying by 2 factors (lack of support from parents, exposure to bullying), verbal bullying by conflicts with parents, physical bullying by 3 factors (lack of support from parents, exposure to isolation and exposure to bullying), and instrumental bullying by lack of support from parents. On the other hand, the pleasure that the bullies feel after bullying behavior was increased by isolation, verbal bullying and physical bullying, while decreased by instrumental bullying. Guilt feeling was decreased by isolation and instrumental bullying, while increased by physical bullying. Isolation increased the tendency of blaming the victim. Isolation and instrumental bullying increased bullies' self-esteem, while social bullying decreased self-esteem. Verbal bullying increased the extent of bullying, while instrumental bullying decreased the extent of bullying. Based on the findings, the intervention strategies to change the bullies' attitudes toward victim, and to increase social support from the significant others as well as the effective ways to reorganize the school environment in order to reduce and prevent bullying behavior were suggested.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.52-60
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• 2005

The conceptual model of under-sampled study area will include a great amount of uncertainty. In this study, we investigate the applicability of Markov chain model in a spatial domain as a tool for minimizing the uncertainty arose from the lack of data. A new formulation is developed to generalize the previous two-dimensional coupled Markov chain model, which has more versatility to fit any computational sequence. Furthermore, the computational algorithm is improved to utilize more conditioning information and reduce the artifacts, such as the artificial parcel inclination, caused by sequential computation. A generalized 20 coupled Markov chain (GCMC) is tested through applying a hypothetical soil map to evaluate the appropriateness as a substituting model for conventional geostatistical models. Comparing to sequential indicator model (SIS), the simulation results from GCMC shows lower entropy at the boundaries of indicators which is closer to real soil maps. For under-sampled indicators, however, GCMC under-estimates the presence of the indicators, which is a common aspect of all other geostatistical models. To improve this under-estimation, further study on data fusion (or assimilation) inclusion in the GCMC is required.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.53-64
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• 2009

Wetlands can remove organic contaminants, metals and radionuclides from wastewater through various biogeochemical mechanisms. In this study, a mathematical model was developed for simulating the fate and transport of chemical species in marsh wetland sediments. The proposed model is a one-dimensional vertical saturated model which is incorporated advection, hydrodynamic dispersion, biodegradation, oxidative/reductive chemical reactions and the effects from external environments such as the growth of plants and the fluctuation of water level due to periodic tides. The tidal effects causes periodic changes of porewater flow in the sediments and the evapotranspiration and oxygen supply by plant roots affect the porewater flow and redox condition on in the rhizosphere along with seasonal variation. A series of numerical experiments under hypothetical conditions were performed for simulating the temporal and spatial distribution of chemical species of interests using the proposed model. The fate and transport of a trace metal pollutant, chromium, in marsh sediments were also simulated. Results of numerical simulations show that plant roots and tides significantly affect the chemical profiles of different electron acceptors, their reduced species and trace metals in marsh sediments.