• Ocean and Polar Research
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• v.41 no.3
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• pp.193-202
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• 2019

There have been various approaches for efficiency improvement of a Darrieus tidal stream turbine after it was introduced as an alternative of horizontal axis turbines. Among the approaches, the researches on the interaction effect of dual configuration were conducted. In this study, a dual Darrieus turbine with a coupling mechanism was proposed for investigating the interaction effect. Also, the effect of bi-directional tidal stream was analyzed with prototype fabrication, apparatus set-up and experiment conduction in indoor and offshore facilities. As the results of the experiments, the dual turbine in case of counter-rotation and inflow between the turbines improved efficiencies by 9.5% and 11.31%, respectively, as compared to the single turbine. Also, the dual turbine in case of the inflow improved efficiencies by 9.4% and 16.62%, respectively, as compared to that in case of outflow between the turbines which represented the case of 180 degrees change of flow direction after slack water. Therefore, the proposed dual turbine showed the advantage in terms of the efficiency as compared to the single turbine and the effect level of the slack water on the performance of the dual turbine was investigated.

• Korean Journal of Childcare and Education
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• v.17 no.4
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• pp.73-91
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• 2021

Objective: This study focused on the relationships between emotionality, social competence and play behavior in a sample of 218 4- to 5-year olds attending daycare centers. Methods: All variables were measured by the daycare teachers of the surveyed children. The data were analyzed using Simple Regression and Multiple Regression through SPSS Win 25.0. Results: First, preschoolers' positive emotionality had a negative effect on their play disruption and play disconnection and a positive effect on play interaction. On the other hand, their negative emotionality had a positive effect on play disruption and play disconnection and a negative effect on play interaction. Second, their positive emotionality had a positive influence on social competence and their negative emotionality had a negative influence. Finally, the effect of their positive emotionality on play disruption was partially mediated, and their play disconnection and play interaction was totally mediated by social competence. On the other hand, the effect of preschoolers' negative emotionality on play disruption and play disconnection was totally mediated, and their play interaction was partially mediated by social competence. Conclusion/Implications: The results of this study imply that we need to help preschoolers promote emotionality and social competence together to change their play behavior positively.

• The Journal of Economics, Marketing and Management
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• v.11 no.1
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• pp.1-12
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• 2023

Purpose: This study identified the effects of the three types of consumer interactions on the utilitarian and hedonic values experienced by community members, their degree of participation, and brand loyalty. In addition, the mediating effect of virtual interactivity between the interactions that occur within the online brand community and the value experienced by community members was also identified. Research design, data and methodology: An online survey was distributed, and the data gathered was analyzed using structural equations modeling. Results: Test results showed that product-information interaction has a positive effect on utilitarian value and interpersonal interaction has a positive effect on hedonic value. Human-computer interaction was found to have a negative effect on hedonic value and no significant effect on utilitarian value. Furthermore, it was revealed that among the three types of interactions, virtual interactivity had a mediating effect only in the relationship between human-computer interaction and hedonic value. Moreover, utilitarian values experienced by community members affected their level of participation which ultimately enhances brand loyalty. Hedonic value did not affect their level of participation within the online brand community. Conclusions: When marketers establish online brand community strategies, they must place elements that can directly help the use of brands and products.

• Journal of Korean Academy of Nursing
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• v.47 no.6
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• pp.854-863
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• 2017

Purpose: The present study is a descriptive cross-sectional study of cause-and-effect relationship, which used the $7^{th}$ year data of the Panel Study on Korean Children, to investigate the effects of parenting stress, depression, and family interactions of the parents of early school-age children on children's subjective happiness. Methods: The present study included data of 1419 pairs of parents who participated in the mother and father survey of the Panel Study on Korean Children. The effects of parenting stress, depression, and parental family interactions on children's subjective happiness were analyzed as actor and partner effects using path analysis. Results: Parenting stress had an actor effect on depression; maternal parenting stress (${\beta}=-.21$, p<.001) and depression (${\beta}=-.30$, p<.001) had an actor effect on maternal family interaction; and paternal parenting stress (${\beta}=-.18$, p<.001) and depression (${\beta}=-.17$, p<.001) had a partner effect on maternal family interaction. Paternal parenting stress was found to have an actor effect on paternal family interaction (${\beta}=-.30$, p<.001), and parental depression was found to have actor effect (${\beta}=-.23$, p<.001) and maternal depression had a partner effect on paternal family interactions (${\beta}=-.22$, p<.001). Children's subjective happiness was found to have a statistically significant relationship with maternal family interaction (${\beta}=.40$, p<.001). Conclusion: The significance of the study is in its provision of basic data for adjusting parents' family interactions that are closely related to the growth and development of children by confirming the effect of parents' parenting stress, depression, and family interaction on children's subjective happiness.

• Journal of the Korean Magnetics Society
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• v.23 no.6
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• pp.188-192
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• 2013

The magnetic interaction effect on the magnetic activation volume and area of electrodeposited CoPt magnetic films was investigated. The dipolar interaction was predominant interaction mechanism for all samples. And the interaction strength was increased with decreasing current density and increased with increasing sample thickness. Although the activation volumes of the samples fabricated at low current density were larger than those of the high current density samples, the sample thickness seemed to have little influence on the variation of activation volume. But it was found that the activation area was apparently affected by the magnetic interaction strength as well as the current density.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.4
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• pp.691-698
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• 2015

The hydrodynamic interaction forces and moments induced by the vicinity of bank on a passing vessel are known as wall effects. In this paper, the characteristics of interaction acting on a passing vessel in the proximity of a semi-circle bank wall are described and illustrated, and the effects of ship velocity, water depth and the lateral distance between vessel and semi-circle bank wall are discussed. For spacing between ship and semi-circle bank wall (SP) less than about 0.2 L and depth to ship's draft ratio (h/d) less than around 2.0, the ship-bank interaction effects increase steeply as h/d decreases. However, for spacing between ship and semi-circle bank wall (SP) more than about 0.3 L, the ship-bank interaction effects increase slowly as h/d decreases, regardless of the water depth. Also, for spacing between ship and semi-circle bank wall (SP) less than about 0.2 L, the hydrodynamic interaction effects acting on large vessel increase largely as ship velocity increases. In the meantime, for spacing between ship and semi-circle bank wall ($S_P$) more than 0.3 L, the interaction effects increase slowly as ship velocity increases.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.475-486
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• 2020

This study aims to discover the mediating effect of Self-Encouragement and Self-Discouragement on the Relationships between Fear of Negative Evaluation and Social Interaction Anxiety. A questionnaire was conducted on 319 university students and the data was analyzed with Pearson's correlation and regression. As a result, there was a positive correlation between Fear of Negative Evaluation and Social Interaction Anxiety. Also, Fear of Negative Evaluation and Social Interaction Anxiety were positively correlated with Self-Discouragement and negatively correlated with Self-Encouragement. Next, multiple regression showed that Self-Discouragement has a perfect mediating effect and Self-Encouragement has a partial mediating effect on the Relationship between Fear of Negative Evaluation and Social Interaction Anxiety. These results imply that counselee with Social Interaction Anxiety can be treated effectively by promoting self-encouragement.

• Journal of Korean Society of Steel Construction
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• v.14 no.6
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• pp.803-811
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• 2002

Current composite steel and concrete bridges are designed using full-interaction theory assuming there is no relative slip, between the steel and concrete components along their interface, because of the complexities of partial-interaction analysis techniques. However, in the assessment of existing composite bridges this simplification may not be warranted as it is often necesary to extract the correct capacity and endurance from the structure. This may only be achieved using partial-interaction theory which tuly reflects the behaviour of the structure. In this paper, Parametric analyses have been carried out in order to confirm the partial-interaction curvatures with deflection effect using the finite element method. Therefore, the model is considered for simply supported steel and concrete composite bridges with a uniform distribution of connectors subjected to a single concentrated load. For the case studies, this study applicate a parameters such as the number and space of stud shear connector and elastic modulus of concrete slabs. From this study, it is known that partial-interaction effect was in the increase to the increasing the deflection of composite bridges, and stiffness and strength of slab concrete considering the occurrence of crack effect seriously to the partial-interaction behavior.

• Coupled systems mechanics
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• v.1 no.4
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• pp.381-395
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• 2012

Dynamic response of Pile Supported Structures is highly depended on Soil Pile Structure Interaction. In this paper, by comparison of experimental and numerical dynamic responses of a prototype jacket offshore platform for both hinge based and pile supported boundary conditions, effect of soil-pile-structure interaction on dynamic characteristics of this platform is studied. Jacket and deck of a prototype platform is installed on a hinge-based case first and then platform is installed on eight skirt piles embedded on continuum monolayer sand. Dynamic characteristics of platform in term of natural frequencies, mode shapes and modal damping are compared for both cases. Effects of adding and removing vertical bracing members in top bay of jacket on dynamic characteristics of platform for both boundary conditions are also studied. Numerical simulation of responses for the studied platform is also performed for both mentioned cases using capability of ABAQUS and SACS software. The 3D model using ABAQUS software is created using solid elements for soil and beam elements for jacket, deck and pile members. Mohr-Coulomb failure criterion and pile-soil interface element are used for considering nonlinear pile soil structure interaction. Simplified modeling of soil-pile-structure interaction effect is also studied using SACS software. It is observed that dynamic characteristics of the system changes significantly due to soil-pile-structure interaction. Meanwhile, both of complex and simplified (ABAQUS and SACS, respectively) models can predict this effect accurately for such platforms subjected to dynamic loading in small range of deformation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4D
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• pp.523-533
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• 2009

The purpose of the present study is to examine the dynamic interaction characteristics between moving maglev vehicle and guideway bridge system. For this purpose, the dynamic governing equation of 2-dof maglev vehicle using optimal feedback control scheme of LQG was derived with or without consideration of the dynamic interaction between vehicle and guideway bridge system. From the parametric study, it was found that the dynamic interaction effect between bridge and vehicle was large in case of neglecting the railway roughness effect. But if the railway roughness effect was considered, it was observed two analysis results with or without consideration of the dynamic interaction did not show big difference. As a conclusion, it is required to take into account the dynamic interaction effect of bridge and maglev vehicle and the railway roughness for precise evaluation of runnability of maglev vehicle and impact factor of guideway.