• Smart Structures and Systems
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• v.3 no.1
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• pp.23-49
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• 2007

Wavelet transforms are the emerging signal-processing tools for damage identification and time-frequency localization. A small perturbation in a static or dynamic displacement profile could be captured using multi-resolution technique of wavelet analysis. The paper presents the wavelet analysis of damaged linear structural elements using DB4 or BIOR6.8 family of wavelets. Starting with a localized reduction of EI at the mid-span of a simply supported beam, damage modeling is done for a typical steel and reinforced concrete beam element. Rotation and curvature mode shapes are found to be the improved indicators of damage and when these are coupled with wavelet analysis, a clear picture of damage singularity emerges. In the steel beam, the damage is modeled as a rotational spring and for an RC section, moment curvature relationship is used to compute the effective EI. Wavelet analysis is performed for these damage models for displacement, rotation and curvature mode shapes as well as static deformation profiles. It is shown that all the damage indicators like displacement, slope and curvature are magnified under higher modes. A localization scheme with arbitrary location of curvature nodes within a pseudo span is developed for steady state dynamic loads, such that curvature response and damages are maximized and the scheme is numerically tested and proved.

• Knowledge Management Research
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• v.17 no.3
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• pp.23-44
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• 2016

This study examined the cause-and-effect relationships among developmental network characteristics, developmental functions, and career identity. The study analyzed the data of employees with more than two years of experience and a college degree or over qualifications, from domestic companies. For analysis, the structural equation model was applied. Most of all, it was substantiated that the structural relationships among the developmental network characteristics, developmental functions, and career identity. The specific results were as follows. First, tie strength had a positive effect on all of developmental functions but psychosocial support mediated the relationship between the tie strength and career identity. Second, an indirect relationship between indicators of network diversity and identity was not found or the indirect relationship was very weak.

• Journal of Korean Public Health Nursing
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• v.28 no.2
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• pp.285-297
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• 2014

Purpose: The purpose of this study was to investigate the structural relationship among the life stress, depression, suicidal ideation of adolescent. Methods: Participants for this study included 285 students from five middle schools located in Seoul and Gyeongsangbukdo, Korea. The SPSS 18.0 program and AMOS 18.0 program were used for analysis of data. Results: The characteristics of this study were to analyze causal relationship with latent variables by considering measurement error and to grasp direct effect, indirect effect and total effect. Life stress and depression were found to be factors influencing suicidal ideation. Depression was a direct factor and life stress was a indirect factor. The effects of depression as a mediator between life stress and suicidal ideation were significant statistically. Conclusion: The findings of this study may provide useful assistance in development of effective nursing interventions for prevention and management of middle school students' suicidal ideation.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.190-197
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• 2000

A moment-curvature relationship to simulate the behavior of reinforced concrete beam under cyclic loading is introduced. Unlike previous moment-curvature models and the layered section approach, the proposed model takes into consideration the bond-slip effect by using monotonic moment-curvature relationship constructed on the basis of the bond-slip relation and corresponding equilibrium equation at each nodal point. In addition, the use of curved unloading and reloading branches inferred from the stress-strain relation of steel gives more exact numerical result. The advantages of the proposed model, comparing to layered section approach, may be on the reduction in calculation time and memory space in case of its application to large structures. The modification of the moment-curvature relation to reflect the fixed-end rotation and pinching effect is also introduced. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed model.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.3-11
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• 2002

A moment-curvature relationship to simulate the behavior of reinforced concrete (RC) columns under cyclic loading is introduced. Unlike previous moment-curvature models and the layered section approach, the unposed model takes into account the bond-slip effect by using a monotonic moment-curvature relationship constructed on the basis of the bond-slip relation and corresponding equilibrium equation at each nodal point. In addition, the use of curved unloading and reloading branches inferred from the stress-strain relation of steel gives more exact numerical result. The pinching enact caused by axial force is considered with an assumption that the absorbing energy corresponding to any deformation level maintains constant regardless of the magnitude of applied axial force. The advantages of the proposed model, comparing tn layered section approach, may be on the reduction in calculation time and memory space in case of its application to large structures.. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed mood.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.185-205
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• 2017

The purpose of this research is to examine the relationship between the adult attachment of married employees, their job motivation and marital relationship. For this purpose, a questionnaire survey was carried out with 370 married employees in the Chungnam area as the target from Sep. 10 to Oct. 14, 2016. The collected data was analyzed using SPSS 23.0 using descriptive statistical analysis, the independent sample T-test, ANOVA analysis, Pearson correlation, and structural equation analysis. First, significant differences were revealed in the level of attachment avoidance, satisfaction with the marriage relationship, and job motivation according to the age group, in the level of attachment avoidance and satisfaction with the marriage relationship according to the education level, in the level of attachment avoidance and satisfaction with the marriage relationship according to the marriage period, in job motivation according to the position, in satisfaction with the marriage relationship according to the average household income, and in satisfaction with the marriage relationship according to the work shift pattern. Second, although a significant negative correlation appeared between attachment anxiety and attachment avoidance, a significant positive correlation was found between attachment avoidance and job motivation. Also, although a significant negative correlation appeared between attachment avoidance and marital relationship, a significant positive correlation was found between job motivation and marital relationship. Third, to examine the mediating effect of satisfaction with the marital relationship on the relationship between adult attachment and job motivation, a structural equation analysis was carried out. As a result, the indirect effect of attachment anxiety on job motivation turned out to be significant and its complete mediating effect was confirmed. This suggests that when developing programs to improve job motivation within the workplace or consultative interventions for the enhancement of marital relationships, the above characteristics of individuals should be taken into consideration.

• Journal of the Korea Safety Management & Science
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• v.11 no.4
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• pp.301-310
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• 2009

The present study analyzed empirically the structural relationship among characters, market orientation and performance of CEO's in small and medium-sized companies. The analysis showed that market orientation is affected by CEO's characters in the industry. It was also revealed from the analysis that the business performance and technical renovation of small and medium-sized companies rely fairly on their market orientation. These findings are believed to have great significance in the process of creating market orientation by the industry. That is, CEO's will may play a very important role in pursuit of market orientation and, at the same time, may act as a vital factor for small and medium-sized companies to achieve business performance and to realize technical renovation.

• Journal of the Korean Home Economics Association
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• v.46 no.9
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• pp.113-123
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• 2008

The purpose of this study was to investigate how parenting and peer relationships influence the development of adolescent self-concept by using Structural Equation Modeling(SEM). The subjects were 198 first graders (94 male and 104 female) from four high schools within the Seoul area. Descriptive and comparative statistical analysis was conducted with SPSS (Version10.0), while AMOS (Version 4.0) was used to assess structural equation modelling of parenting, peer relationship and the self-concept. Results showed that, in terms of correlation, more positive parenting behaviors induced more positive self-concept. In addition, better peer relationships demonstrated more positive self-concept. Regression analysis showed that peer relationships explained the variance in adolescents' self-concept more effectively than parenting behavior. This was confirmed by the SEM.

• International journal of advanced smart convergence
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• v.12 no.3
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• pp.192-199
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• 2023

The purpose of this study was to investigate the structural relationship between eating habits, physical activity, and subjective health perception, which can affect the mental health status of adolescents, and to examine whether subjective health perception has a mediating effect in these relationships. In this study, raw data from the "17th 2021 Youth Health Behavior Online Survey" were used, and a total of 1,998 people were used for the analysis of Gangwon-do adolescents, except for data with missing values. For analysis, SPSS 25.0 and AMOS 25.0 programs were used to analyze descriptive statistics, t-test, and structural equation models(SEM). Physical activity was found to have a positive and significant effect on mental health status, and subjective health cognition showed the effect of physical activity mediating mental health status.

• Korean Journal of Social Welfare Studies
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• v.42 no.2
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• pp.179-203
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• 2011

The purpose of the study is 1) to investigate the reciprocal relationship between cognitive functioning and depressive symptoms and 2) to examine whether there is gender difference in this mutual relationship. The uniqueness of the current study is in its investigation on the simultaneous reciprocal relationship between cognitive functioning and depressive symptoms, which is different from previous studies examining unidirectional relationship. Subjects were 3,511 individuals aged 65 and over who participated in the first and second wave of Korean Longitudinal Study of Ageing. Non-recursive structural equation modeling identified the reciprocal relationship between cognitive functioning and depressive symptoms, with poorer cognitive functioning leading to higher depressive symptoms and higher depressive symptoms resulting in poorer cognitive functioning. Multi-group analysis showed the gender difference in the relationship between cognitive functioning and depressive symptoms. Specifically, cognitive functioning was the significant predictor of depressive symptoms for females, whereas the depressive symptoms was the significant predictor of cognitive functioning for males. These findings indicate that the reciprocal relationship and gender difference should be considered when we development practice implications for prevention and treatment related to depression and cognitive functioning. Based on these findings, implications for theory and practice were discussed.