• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.215-224
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• 2001

An experimental investigation was conducted on the interaction of vortices over a delta wing with the leading edge extension for three angles of attack($16^{\circ},\; 24^{\circ} \;and\; 28^{\circ}$) at Reynolds number of $1.76{\times}10^6.$ The experimental data included total pressure contours and velocity vectors using 5-hole probe measurements. Constant total pressure coefficient contours show the LEX vortex moves downward and outboard, while the wing vortex exhibited an inboard and upward migration. At near the trailing edge, these vortices reveal a direct interaction between the wing and LEX vortex, featuring a coiling of vortex cores about each other. The combined effect of the interaction of these two vortices and proximity to the wing surface results in the increase of the suction peak. This is in contrast to the result obtained on the delta wing alone configuration, where the effect of the vortex breakdown was manifested. The interaction of the wing and LEX vortices is more pronounced at higher AOA.

• Journal of Power System Engineering
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• v.12 no.6
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• pp.29-35
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• 2008

This study is conducted to provide the proper analysis method to evaluate the stability of a container crane under wind load. Two analysis method, namely structure analysis and fluid-structure interaction, are adopted to evaluate the stability of a container crane in this investigation. To evaluate the effect of wind load on the stability of the crane, 50-ton class container crane widely used in container terminals is adopted for analysis model and 19-values are considered for wind direction as design parameter. We conduct structure analysis and fluid-structure interaction for a container crane with respect to the wind direction using ANSYS and CFX. Then we compare the uplift forces yielded from two analysis with it yielded from wind tunnel test. The results are as follows: 1) A correlation coefficient between structure analysis and wind tunnel test is lower than 0.65(as $0.29{\sim}0.57$), but between fluid-structure interaction and wind tunnel test is higher than 0.65(as $0.78{\sim}0.86$). 2) There is low correlation between structure analysis and wind tunnel test but very high correlation between fluid-structure interaction and wind tunnel test.

• The Korean Journal of Health Service Management
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• v.12 no.1
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• pp.149-160
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• 2018

Objectives : The purpose of this study was to examine the mediating effect of professional self-concept on the relationship between professor-student interaction and job-seeking anxiety among nursing students. Methods : A cross-sectional survey was conducted using a convenient sampling method with data collected from a sample of 294 nursing students. The structured questionnaire included items to assess job-seeking anxiety, professional self-concept, and professor-student interaction among nursing students. The data were analyzed with descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression using the SPSS 24.0 program. Mediation analysis was performed according to the Sobel test. Results : Analysis of the mediating effect of professional self-concept showed a significant mediating influence of professional self-concept on the relationship between professor-student interaction and job-seeking anxiety. Conclusion : The findings suggest that professional self-concept may play a role in increasing the effect of professor-student interaction on job-seeking anxiety. Therefore, this study underscores the need to consider ways of enhancing professional self-concept during interventions for nursing students.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.297-302
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• 2008

Application of genotype by environment ($G\;{\times}\;E$) interaction would be used for identifying optimum test condition of the varietal adaptation in the establishment of breeding purpose. Yield and yield components were used to perform additive main effect and multiplicative interaction (AMMI) analysis. Significant difference for $G\;{\times}\;E$ interaction were observed for all variable examined. For yield, 0.18 of total sum of squares corresponded to $G\;{\times}\;E$ interaction. Correlation analysis was carried out between genotypic scores of the first interaction principal component axis (IPCA 1) for agronomic characters. Significant correlations were observed between IPCA 1 for yield and capsule bearing stem length (CBSL), number of capsule per plant (NOC). The biplot of grain yield means for IPCA1 which accounted for 34% of the variation in total treatment sums of squares showed different reaction according to $G\;{\times}\;E$ interaction, genotypes and environments. Taegu showed relatively lower positive IPCA1 scores, and it also showed smaller coefficient variation of yield mean where it is recommendable as a optimal site for the sesame cultivar adaptation and evaluation trial. In case of variables, Yangbaek and M1 showed relatively lower IPCA1 scores, but the score direction showed opposite each other on the graph. Ansan, Miryang1, Miryang4, and Miryang6 seemed to be similar group in view of yield response against IPCA1 scores. These results will be helpful to select experimental site for sesame in Korea to minimize $G\;{\times}\;E$ interaction for the selection of promising genotype with higher stability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.417-424
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• 2020

There is increasing tension and anxiety about being evaluated by others such as anxiety, which is felt when others' evaluation is expected or actual, and this is called social interaction anxiety. The purpose of this study was to develop a nursing intervention program that can reduce social interaction anxiety among nursing college students by analyzing factors affecting social interaction anxiety in nursing college students. The subjects of this study were four nursing college students in B city and C city. The survey data were analyzed using frequencies, percentages, means, t-test, ANOVA, Pearson correlation coefficient, and stepwise multiple regression with the SPSS WIN 21.0 program. The results of this study show that social interaction anxiety was positively correlated with fear of negative evaluation (r=.67, p<.001), fear of positive evaluation (r=.56, p<.001), and intolerance of uncertainty (r=.44, p<.001). Factors affecting ambivalence over emotional expressiveness in terms of social interaction anxiety was interpersonal relationship (β=.19, p<.001), fear of negative evaluation (β=.43, p<.001), and fear of positive evaluation (β=.34, p<.001). The explanatory power of these variables was 58.1%. Therefore, it is thought that nursing college students need to provide a support system to maintain good interpersonal relationships, to reduce sensitivity to positive and negative evaluation, and to accept and positively evaluate their own ability.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3429-3432
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• 2011

Distribution diagram of $FeCl_2$ in HCl solution indicated that $FeCl^+$ was a predominant species in strong HCl solution up to 10 M. Solvent extraction of $FeCl_2$ has been performed in the HCl concentration range from 5 to 9 M by using Alamine336 as an extractant. Interaction parameter of $FeCl^+$ for Bromley equation was estimated from our solvent extraction data. This parameter thus obtained in our study can be employed in calculating the activity coefficient of $FeCl^+$ in high concentration of HCl.

• Geomechanics and Engineering
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• v.12 no.6
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• pp.949-963
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• 2017

The main purpose of the current study is to develop the new coefficients for consideration of soil-structure interaction effects to find the elevated tank natural period. Most of the recommended relations to find the natural period just assumed the fixed base condition of elevated tank systems and the soil effects on the natural period are neglected. Two different analytical systems considering soil-structure- fluid interaction effects are recommended in the current study. Achieved results of natural impulsive and convective period, concluded from mentioned models are compared with the results of a numerical model. Two different sets of new coefficients for impulsive and convective periods are developed. The values of the developed coefficients directly depend to soil stiffness values. Additional results show that the soil stiffness not only has significant effects on natural period but also it is effective on liquid sloshing wave height. Both frequency content and soil stiffness have significant effects on the values of liquid wave height.

• Earthquakes and Structures
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• v.4 no.3
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• pp.285-297
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• 2013

The effect of soil structure interaction (SSI) on seismic response of a multi-degree-of-freedom structure isolated with a friction pendulum system (FPS) is studied. In the analysis, the soil is considered as an elastic continuum and is modeled using the finite element method. The effect of SSI on response of the structure is evaluated for twenty far-field and twenty near-fault earthquake ground motions. The effect of friction coefficient of sliding material of FPS on SSI is also studied. The results of the study show that the seismic response of the structure increases for majority of the earthquake ground motions due to SSI. The sliding displacement and base shear are underestimated if SSI effects are ignored in the seismic analysis of structures isolated with FPS.

• Elastomers and Composites
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• v.55 no.3
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• pp.229-234
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• 2020

Automobile wiper blades are generally treated with chlorine to lower their friction coefficient with the windshield surface. This treatment could affect the crosslink density measurement of rubber vulcanizates, a material used in windshield wipers, which would consequently alter its chemical and physical properties. Therefore, this study evaluated the influence of chlorination on crosslink density measurements of natural rubber (NR) vulcanizates using a vehicle wiper blade. A method for determining the degree of chlorination was developed where the interaction parameter between the rubber and the swelling solvent was corrected. A decrease in the rubber sample swelling ratio was observed upon chlorination, and the chlorination penetrated less than 1% of the sample thickness. The chlorinated NR was assumed to be chloroprene rubber (CR), which was used to correct the interaction parameter. The results showed the CR contributed approximately 7% to the parameter.

• 유체기계공업학회:학술대회논문집
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• 1999.12a
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• pp.163-169
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• 1999

The numerical procedure has been developed for simulating incompressible viscous flow around a turbine stage with rotor-stator interaction. This study solves 2-D unsteady incompressible Navier-Stokes equations on a non-orthogonal curvilinear coordinate system. The Marker-and-Cell concept is applied to efficiently solve continuity equation. To impose an accurate boundary condition, O-H multiblocked grid system is generated. O-type grid and H-type grid is generated near and outer rotor-stator The cubic-spline interpolation is applied to handle a relative motion of a rotor to the stator. Turbulent flows have been modeled by the Baldwin- Lomax turbulent model. To validate present procedure, the time averaged pressure coefficients around the rotor and stator are compared with experiment and a good agreement obtained.