• 한국소음진동공학회논문집
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• 제15권5호
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• pp.527-535
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• 2005

This paper explains a general coupling system in terms of the system parameters. impedance of a cavity or mobility of a structure. To easily access the mechanism of the structural-acoustic coupled system, a simple expression is derived. A general coupled equation is also derived of a general coupled problem constituted a flexible structure and an opening boundary in terms of vector and matrix notation, and is analyzed the coupling phenomena using the understanding acquired simple coupled system. The paper shows that the general coupled equation is expanded version of the simple coupled equation by some limiting checks. The paper also shows that the degree of coupling is proportioned to a stiffness of the acoustic system and a modal coupling coefficient, but is in inverse proportion to a mass of the structural system and the difference of the excitation frequency and resonant frequency of the acoustic or structural system.

• 한국공간구조학회논문집
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• 제3권3호
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• pp.85-93
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• 2003

Steel, concrete and their combination materials are the most 6commonly used materials for civil engineering structural systems such as buildings, bridge structures and other structures. Recently, however, fiber reinforced polymer (FRP) composites, a relatively new composite material made of fibers and polymer resins, have been gradually used in structural systems as an alternative structural material. This paper describes a comparison of design strength equations for steel column and FRP composite column based on design philosophies. The safety factors used in allowable stress design (ASD) are relatively higher in FRP structural design than steel structural design. Column critical stress equations of FRP composites column from an experimental study can be represented by Euler elastic buckling equation at the long-range of slenderness, and an exponential form at the short-range of slenderness as defined in Load and Resistance Factor Design (LRFD) of steel column. The column strength of steel and FRP composite columns in large slenderness is independent of material strength, this result verified the elastic buckling equation as derived by Eq. (15) and Eq. (5).

• 경영정보학연구
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• 제16권3호
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• pp.89-112
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• 2014

본 튜토리얼은 PLS 경로분석 수행을 지원하는 R 패키지인 "plspm"을 이용하여 구조방정식모형을 분석하는 방법을 제시하고 있다. 본 튜토리얼에서는 이를 위해 기존 연구들에서 제시하고 있는 PLS구조방정식모형을 분석하기 위한 기준들을 정의하고, 하나의 예시 연구모형을 제시하여 실질적으로 R을 이용하여 이 예시 모형을 분석하는 것을 보여준다. 본 튜토리얼은 PLS를 처음 접하는 연구자들에게는 연구모형에 대한 실증분석을 위한 유용한 가이드가 될 것이며, 이미 PLS에 익숙한 연구자들에게는 R을 이용한 새로운 PLS 구조방정식모형 분석기법 제시를 통하여 R이라는 통합된 통계 소프트웨어 운영환경에서 심도 있는 분석을 위한 기반 지식을 제공할 것이다.

• 대한영양사협회학술지
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• 제25권2호
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• pp.142-155
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• 2019

The aim of this study was to construct and test a structural equation model for the risk factors of metabolic syndrome in Korean adults. The structural equation model hypothesizes that eating alone and feeling depressed is a risk factor for metabolic syndrome. The data of this study were obtained from the Sixth Korea National Health and Nutrition Examination Survey which was cross-sectional data from the representative national survey. A total of 4,013 subjects replied to the survey item of lifestyle and completed the physical examinations among adults aged 19 years or older in South Korea was in 2015. The structural model in this study was composed of four latent variables: eating alone, depression, negative health behavior, and metabolic syndrome. Two variables, the rate of eating alone and depression, were exogenous variables. Negative health behavior was both a mediating variable and endogenous variable, and metabolic syndrome was the final endogenous variable. The data were analyzed using the Maximum Likelihood method and bootstrapping. The structural model was appropriate for the data based on the model fit indices. The results of this study can be summarized as follows: Eating alone is a direct risk factor of metabolic syndrome in Korean women. Depression can mediate metabolic syndrome through negative health behaviors. Negative health behavior had a direct impact on metabolic syndrome in both men and women. This study may be a guideline for interventions and strategies to reduce the incidence of metabolic syndrome in Korean adults.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제7권4호
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• pp.247-270
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• 2003

The purpose of this study is to build a model that explains the relationship between and among five variables that are student background, teacher background, home environment, school characteristic, and student mathematics achievement, using structural equation modeling. Another purpose of this study is to compare the relationships of these variables between the United States and Korea in 7th and 8th grades mathematics. Student, teacher, and school background files from population 2 in the TIMSS were selected for this study. The result of the study provides practical information for teachers, parents, school principals, and other people who are interested in improving student achievement, and also provides the information that may explain differences and similarities between the US and Korea in mathematics achievement.

• 품질경영학회지
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• 제30권3호
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• pp.38-52
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• 2002

This paper is concerned with the analysis of structural equation model(SEM) with the ordinal data such as Likert scale. The SEM is misused when the arbitrary scores allocated to the Likert scale are treated as quantitative data. The underlying distribution approaches have been studied to solve this problem, and the partial least squares(PLS) Is also tried. In this paper the quantification methods for the Likert scale are proposed to analyze the SEM. We assume that the Likert scale is an observation of the interval of the continuous underlying distribution, and the respondents have their own patterns in the response of some questions. Normal and beta distributions as the response patterns are considered to quantify the Likert scale. To compare the efficiency of the proposed method the bootstrap simulations are tried.

• 감성과학
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• 제16권4호
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• pp.567-578
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• 2013

The research is a correlational study to look for causes and factors relating to the design of written documents (professional reading materials) and identify those relationships that are useful for communication designers. The research specifically targeted the relationships between perception and reader's past experiences and appearance of the written documents. A preliminary survey, such as interviews, discussions, questionnaires and brainstorming sessions are conducted to establish the observable attributes related to perception which are reader's interests, importance of information and written documents complexity. Finally, the research used Structural Equation Model (SEM) to identify significant differences and analyze strong and weak correlations between these attributes. In general, the results of the study shows that the attribute appearances of a written documents with excellent visualizations for information display shows a strong correlation with interests while the attributes importance is weakly correlated with the complexity of the documents.

• 대한가정학회지
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• 제40권5호
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• pp.133-146
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• 2002

The purpose of this study was to verify a Structural Equation Model that constructed the causations among the leisure resources, health perception, leisure attitude, leisure satisfaction and the quality of life in the elderly. For the purpose, 208 elderly who were over sixty years old and inhabited in Seoul were given questionnaires. Questionnaires were distributed by means of a 1:1 personal interview method. A Measurement model and a structural equation model estimates by Maximum Likelihood method(ML method) utilizing LISREL 8.51 ver. The major results are summarized as follows: 1) A Goodness of fit is good of structural equation model presented in the study. 2) The higher their leisure resource is, the higher health perception is, the higher leisure attitude is the more leisure satisfaction. 3) The important valuable factor which affected the quality of life in the elderly was the leisure satisfaction. It showed powerfully if the elderly participate enjoyment, self-development and positive leisure activity, their leisure satisfaction would increase, consequently the Quality of life would be improved.

• 유통과학연구
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• 제18권7호
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• pp.5-17
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• 2020

Purpose: The purpose of this study is to examine the influence of resilience and work engagement on performance of managers in the automotive sector in Morocco. It analyses the mediating effect of work engagement between resilience and manager performance. Though earlier studies have focused on the effect of resilience on employee performance and work engagement. none has looked at the mediating role of work engagement in this context. Thus, the present paper attempts to fill this literature gap. Research design, data and methodology: A confirmatory survey was conducted among a sample of 196 employees of automobile companies in Tangier-Morocco. A structural equation analysis using SmartPLS was performed while Preacher and Hayes (2008) method was used to analyze the mediation effect. Results: a) Manager resilience has a positive influence on work engagement, which further influences their performance; b) there is a statistically insignificant relationship between resilience and manager performance; c) Structural equation modelling analysis shows that work engagement partially mediates the relationship between resilience and manager performance. Conclusion: Theoretical contributions, practical implications, and future research directions are discussed.

• 디지털융복합연구
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• 제6권1호
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• pp.83-91
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• 2008

The objective of this research is to assess various factors affecting E-learning in Korean language education. In this research, we hypothesize that several factors such as absorption, motivation and tutors increase the educational effects of E-learning and ultimately affect learning attitude and satisfaction of students in E-learning. To discuss the hypothesis, we analyzed survey data of 300 students who were taking E-learning class of Korean language for three weeks in October 2007 based on Structural Equation Model. The result of our analysis shows that the factors such as absorption, motivation, tutors have positive effects on E-learning in Korean language education and positive influence on learning attitude and satisfaction on students as well.