• Computers and Concrete
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• v.33 no.6
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• pp.725-738
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• 2024

This study presents a macro-modeling procedure for nonlinear finite element analysis of reinforced and prestressed concrete panels under blast loading. The analysis procedure treats cracked concrete as an orthotropic material based on a smeared rotating crack model within the context of total-load secant stiffness-based formulation. A direct time integration method compatible with the analysis formulation is adapted to solve the dynamic equation of motion. Considerations are made to account for strain rate effects. The analysis procedure is verified by modeling 14 blast tests from various sources reported in the literature including a blast simulation contest. The analysis results are compared against those obtained from experiments, simplified single-degree-of-freedom (SDOF) methods, and sophisticated hydrocodes. It is demonstrated that the smeared crack macro-modeling approach is a viable alternative analysis procedure that gives more information about the structural behavior than SDOF methods, but does not require detailed micro-modeling and extensive material characterization typically needed with hydrocodes.

• Journal of the Korean Society of Safety
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• v.28 no.2
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• pp.78-83
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• 2013

The traffic culture index is used as a major index in evaluating the traffic safety services of local governments and also serve as important data for the planning and implementation of traffic safety services. However, as the traffic culture index gradually became a standard for comparison among local governments, in part, certain cases arose which questioned the grounds for selecting variables for the index and the validity of the index in terms of its influential relationship between evaluation items. This study analyzed the index's influential relationship by utilizing a PLS structural equation model based on the evaluation results of the 2011 traffic culture index. A variable-linking model was created which recognized the relativity taking into account of the indirect effects between latent variables and this model was proven to be a model suitable in explaining the traffic culture index with a 97.8% explanation power. It was found that traffic safety(0.530), driving behavior(0.527), pedestrian behavior(0.187) and vulnerable road users(0.147), in such order, had an effect on the traffic culture index. It was also found that human casualties due to traffic accidents under "traffic safety" and traffic light compliance rate under "driving behavior" had an important effect. The study showed that motor vehicle share in illegal parking in school zones did not have a valid explanation power regarding "vulnerable road users".

• Journal of Global Scholars of Marketing Science
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• v.17 no.3
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• pp.133-151
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• 2007

The purpose of this article is to examine the effects of item parceling on the consistency of significance testing of the causal parameters with regard to the relationship between the relevant constructs, as well as the effects of the item parceling on the goodness-of-fit indices of LISREL's general models. Most of the researchers' major purpose of using structural equation modeling (SEM) is to test their research hypotheses associated with the causal parameters. Therefore, we investigated three general models of LISREL, rather than the frequently used confirmatory factor analytic (CFA) models by many other researchers. The results of the study showed that there was a high level of consistency in the calculated test statics of causal parameters between the item-parceled solutions and the item-level solutions, and that the item-parceled solutions had better goodness-of-fit indices, such as GFI, AGFI, CFI, and NFI, than the solutions at the item level. However, in terms of RMSEA, there was no such tendency.

• Journal of the Korean Home Economics Association
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• v.45 no.3
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• pp.109-120
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• 2007

The purposes of this study were to provide evidence concerning the effects of Emotional Leadership and examine the impacts of Emotional Leadership on employee-related variables which were 'job satisfaction', 'organizational commitment', 'organizational performance', 'turnover intention'. A survey was conducted from August 23 to November 3, 2005 to collect data from kitchen staff(N=611). Statistical analyses were completed using SPSS Win(12.0) for descriptive analysis, reliability analysis, factor analysis, t-test, correlation analysis, cluster analysis and AMOS(5.0) for structural equation modeling. Kitchen staffs gave high point to their leader in the Emotional Leadership competence 'Optimism: seeing the upside in events' and 'Adaptability: flexibility in handing change' and gave lower point in the Emotional Leadership competence 'Inspirational leadership: guiding and motivating with compelling vision'. Employees' job satisfaction on 'coworker' were relatively high. However, the extents of satisfaction on 'payroll', 'promotion', 'work environment' were relatively low. The organizational commitment score was higher at 'loyalty' factor than 'commitment' factor. the test of hypothesis using structural equation modeling found that Emotional Leadership produced positive effects on job attitude and job performance. In conclusion, this study has identified that the Emotional Leadership effects on their organizational performance and attitudes toward their job.

• Journal of the Korea Convergence Society
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• v.11 no.3
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• pp.291-299
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• 2020

Purpose: This study was to analyze a structural equation model of parents attitudes, family function, self-management, and career decision making self-efficacy in high school girls. Method: The high school girls was asked to complete a questionnaire, and 255 data units were analyzed with Structural Equation Modeling. Result: The hypothetical model fit indices for the model revealed a fit at a recommended level(χ²/df=2.84, GFI=0.91, SRMR=0.05, NFI=0.91, CFI=0.93, RMSEA=0.08), and 6 of the 9 paths were statistically significant explaining 48% of the variance. Conclusion: In order to improve the career decision making self-efficacy for high school girls, it is necessary to be able to develop and practice self-management through the improvement of home and family functions.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.139-144
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• 2005

A rigorous research is underway in our team, for the design and development of high figure of merits (ZT= 1.5${\sim}$2.0) micro-thermoelectric coolers. This paper discusses the fabrication process that we are using for developing the $Sb_2Te_3-Bi_2Te_3$ micro-thermoelectric cooling modules. It describes how to obtain the mechanical properties of the thin film TEC elements and reports the results of an equation-based multiphysics modeling of the micro-TEC modules. In this study the thermoelectric thin films were deposited on Si substrates using co-sputtering method. The physical mechanical properties of the prepared films were measured by nanoindentation testing method while the thermal and electrical properties required for modeling were obtained from existing literature. A finite element model was developed using an equation-based multiphysics modeling by the commercial finite element code FEMLAB. The model was solved for different operating conditions. The temperature and the stress distributions in the P and N elements of the TEC as well as in the metal connector were obtained. The temperature distributions of the system obtained from simulation results showed good agreement with the analytical results existing in literature. In addition, it was found that the maximum stress in the system occurs at the bonding part of the TEC i.e. between the metal connectors and TE elements of the module.

• Journal of Digital Convergence
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• v.15 no.5
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• pp.419-429
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• 2017

This study examined the moderating effects of gender on the effects of anxiety and depression on college students' smartphone addiction. For this purpose, 331 students in Gyeonggi province were conducted a survey, and a structural equation modeling was used. The results showed that female had higher levels of anxiety, depression, and smartphone addiction than male. Second, the analysis of structural equation modeling to investigate the effect of anxiety and depression on smartphone addiction revealed that depression affects smartphone addiction. Third, gender had a moderating effect on the effects of anxiety and depression on smartphone addiction. Anxiety affected male, while depression worked on female. Based on the results of this study, it was discussed that different approaches are needed depending on gender in preventing and intervention for smartphone addiction.

• 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.

• Journal of Digital Convergence
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• v.14 no.9
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• pp.111-121
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• 2016

This study provides an approach to perform the double mediation analysis in structural equation models using the R. For this purpose, the study reviews a variety of techniques for mediation analysis, selects the bootstrapping technique as the most suitable way for performing the double mediation analysis and develops an approach for the double mediation analysis in structural equating models with the bootstrapping using the plspm which is the R package for the performing PLS path analysis. This study will be useful for the studies including the double mediation analysis in structural equation modeling, which is not supported by most of SEM packages, also will provide the knowledge base for in-depth analysis through suggesting the new mediation analysis technique using R for the researchers.

• Journal of Korean Academy of Nursing
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• v.38 no.5
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• pp.639-648
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• 2008

Purpose: This study was designed to construct and test a structural equation model on sexual function in women with gynecologic cancer. Methods: The model was constructed and tested under the hypotheses that women's physical changes in sexual function after gynecologic cancer treatment did not automatically lead to sexual dysfunctions. Women's psychosocial factors were considered to be mediating variables. Two hundred twelve women with cervical, ovarian, and endometrial cancer were recruited and asked to complete a survey on their physical factors, psychosocial factors and sexual function. Data was analyzed using SPSS WIN 12.0 and Amos WIN 5.0. Results: Predictors of sexual function in the final model were sexual attitude affected by physical distress and couple's age, sexual information affected by physical distress and couple's age, depression affected by physical distress, and marital intimacy affected by physical distress. Tumor stage and time since last treatment directly affected women's sexual function without any mediating psychosocial variables. However, body image did not affect women's sexual function. Conclusion: Nursing professionals should develop a tailored educational program integrating both physical and psychosocial aspects, and apply it to women and their spouses in order to promote sexual function in women with gynecologic cancer.