• Journal of Drive and Control
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• v.16 no.4
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• pp.65-73
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• 2019

In this study, flow analysis and fluid-solid interaction analysis were conducted on a hollow fiber membrane module used for analysis of dehumidification characteristics. To ensure the reliability of the flow analysis results, the dehumidification experiment was performed under the temperature of 30℃ and relative humidity of 30% RH. The results of the dehumidification experiments were compared with the flow analysis results. The results of dehumidification experiments and flow analysis had a difference of approximately 5%. A 1-Way fluid-solid interaction analysis with various materials was conducted. From the results, it was found that the baffle with the largest shape deformation (polyethylene material) was subjected to 2-way fluid-solid interaction. The analysis of fluid flow and dehumidification characteristics were analyzed according to the shape deformation of the baffle.

• International Journal of Aerospace System Engineering
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• v.8 no.1
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• pp.1-13
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• 2021

Contra-rotating fan is comprised of two rotors which are rotating in the opposite direction. The fan stages are named rotor-1 and rotor-2. Benefits from the use of contra rotation are in terms of better efficiency and improved thrust to weight ratio. Failure of contra-rotating fan stage blade in-service results in safety risks, repair costs, and revenue losses. This paper focuses on the vibration analysis and one way fluid-structure interaction of high aspect ratio, low speed contrarotating fan rotors. Modal analysis and modal pre-stress analysis of contra-rotating fan rotors were carried out to calculate the natural frequencies, One way fluid-structure interaction (FSI) was carried out where the computational analysis of the blades was performed using ANSYS CFX. The boundary conditions for CFD analysis were considered from the actual experimental velocity flow field at the inlet and pressure outlet. Based on the results obtained from the CFD analysis, the structural analysis such as deformation and Von-Misses stresses was carried out by using the finite element method (FEM) with ANSYS. The results provide necessary guidelines for the safe running of the contra-rotating fan. The analysis also will be helpful to understand the change of flow behavior due to a rotor deformation.

• Journal of Applied Reliability
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• v.17 no.1
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• Structural Engineering and Mechanics
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• v.8 no.1
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• pp.53-72
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• 1999

The most important features of linear soil-foundation-structure interaction are reviewed, using stochastic modeling and considering kinematic interaction, inertial interaction, and structural distortion as three separate stages of the dynamic response to the free-field motion. The way in which each of the three dynamic stages modifies the spectral density of the motion is studied, with the emphasis being on interpretation of these results, rather than on the development of new analysis techniques. Structural distortion and inertial interaction analysis are shown to be precisely modeled as linear filtering operations. Kinematic interaction, though, is more complicated, even though it has a filter-like effect on the frequency content of the motion.

• Korean Journal of Child Studies
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• v.10 no.1
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• pp.26-42
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• 1989

This study was designed to investigate the relation between mother's interaction strategies and self-regulation of young children from a Vygotskian perspective. The hypotheses of this study were: 1) The self-regulation of young children will improve with increase in age, 2) the use of mothers' interaction strategies will increase as child's age decreases, 3) mothers' directiveness in the mother-child interaction depends on the age of child and socio-economic level, and 4) mothers' directiveness in the mother-child interaction will have negative relationship with child's self-regulation. The subjects of this study were 60 mother-child dyads with three different age-of-child groups (3-, 4-, and 5-year-olds). They were further divided into higher and lower socio-economic groups. A puzzle task was used for the measurement of self-regulation. The task consisted of two identical puzzles with one used as the model. The collected data were analyzed by ${\chi}^2$, one-way and two-way analysis of variance, and Pearson's r. Self-regulation of the young children improved with increase in age (P < .05). The use of mothers' interaction strategy decreased as the children's age increased (P < .05). Mothers' directiveness in the mother-child interaction was influenced by the age of child (P < .01) and by socioeconomic level (P < .05). There was a negative correlation (r=-.848) between the mothers' directiveness in the mother-child interaction and the child's self-regulation (P < .001).

• Korean Journal of Childcare and Education
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• v.18 no.1
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• pp.1-22
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• 2022

Objective: This study attempted to verify the effectiveness of parent education programs which emphasize parents' direct interaction with young children even when using digital devices. For this purpose, parents' play beliefs and their interaction with their children were evaluated by taking a pre-test and post-test. Methods: The subjects of this study were parents of young children attending child care centers. The collected data were analyzed by one-way covariate analysis (ANCOVA) to find out if there was a significant difference in post-test scores after controlling the pre-test as a covariate to minimize possible errors between groups before the experiment. Results: Parents, who had participated in the parent education program which emphasized parents' direct interaction with young children when using digital devices, showed higher increases of play support beliefs and parent-child interaction than the comparative group. Conclusion/Implications: This study confirmed that in order to develop digital fluency from early childhood, parents should avoid indiscriminate use of digital devices at home, maintain direct interaction with their children even when giving them digital devices to play with, and support healthy growth by way of continuing sensitive interaction with their children.

• Journal of Korean Society on Water Environment
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• v.39 no.4
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• pp.261-268
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• 2023

The benthic macroinvertebrates index (BMI) was developed based on the 5-day biochemical oxygen demand (BOD₅), which is the amount of biodegradable organic matter in stream water. However, benthic macroinvertebrates mainly live in the streambed substrate and are affected by the interaction of water quality and substrate. This study was conducted to examine the interactive relationship between water quality items (BOD₅, total phosphorus (TP), total suspended solids (TSS)) and substrate with BMI by performing statistical analyses (four-way analysis of variance, Pearson's correlation analysis, partial correlation analysis and multiple regression analysis). The data used in the analyses were collected from 19,915 sampling units at 1,937 sites in South Korea from 2010 to 2020. The interaction effect between BOD₅ and substrate types was confirmed through a four-way analysis of variance. Partial correlation analysis and multiple regression analysis estimated the degree of influence on the change in BMI value in the order of mean grain size of the substrate as (𝜱_m) > BOD₅ > TP > TSS. BMI can be regarded as an index that evaluates the comprehensive effects of water quality and streambed status, although it is an index that was developed based on the amount of biodegradable organic matter in a water column.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1048-1050
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• 2017

In this study, Numerical simulations of the pintle-nozzle were performed to evaluate the thermal strain effect using by 1-way fluid structure interaction analysis(FSI). we carried out computational fluid dynamics analysis to obtain the pressure and temperature fields of pintle nozzle. we then used the data as the load condition for a FSI separately. and thermal strain of the pintle was checked. In order to confirm the change of thrust characteristic by deformation, we are carrying out 2-way FSI.

• Journal of the Korean Society of Visualization
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• v.4 no.1
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• pp.41-46
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• 2006

In this study, one-way fluid structure interaction analysis(FSI) on wind turbine blade was performed. Both a quantitative fluid analysis on 3-bladed wind turbine and a structural analysis using the surface pressure data resulting from fluid analysis were carried out. Streamlines and angle of attack was easily acquired from analysis results, we showed the inlet velocity that the stall begins to occur. In the structural analysis, structural displacement and maximum stress of the two comparative models was calculated. The location that has maximum stress was found. The pressure difference between back and front part of the blade increases as the inlet velocity increase. The torque and maximum with regard to inlet velocity was also presented.

• Genomics & Informatics
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• v.16 no.4
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• pp.38.1-38.3
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• 2018

Gene-gene interaction (GGI) analysis is known to play an important role in explaining missing heritability. Many previous studies have already proposed software to analyze GGI, but most methods focus on a binary phenotype in a case-control design. In this study, we developed "Hierarchical structural CoMponent analysis of Gene-Gene Interactions" (HisCoM-GGI) software for GGI analysis with a continuous phenotype. The HisCoM-GGI method considers hierarchical structural relationships between genes and single nucleotide polymorphisms (SNPs), enabling both gene-level and SNP-level interaction analysis in a single model. Furthermore, this software accepts various types of genomic data and supports data management and multithreading to improve the efficiency of genome-wide association study data analysis. We expect that HisCoM-GGI software will provide advanced accessibility to researchers in genetic interaction studies and a more effective way to understand biological mechanisms of complex diseases.