• Title/Summary/Keyword: Structural Equation Analysis

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The moderating effects Analysis of followership according to the MMR & SEM methods to leadership and empowerment in IT SMEs (IT중소기업의 리더십과 임파워먼트에서 MMR과 SEM 검증방법에 따른 팔로워십 조절효과분석)

  • Lee, Yeong Shin;Park, Jae Sung
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.3
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    • pp.199-212
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    • 2012
  • This study focuses on the influence of followership on leadership and empowerment, and to verify based on the control variables taken in IT SME's to enhance competitiveness through innovation and improvement plan that have been taken. Because there can be a lot of information to be taken, the laws of Moderated Regression Multiple analysis(MMR) were used. Amos, due to the moderating effect of Structural Equation Modeling(SEM) has been employed to re-verify the results seen with Moderated Regression Multiple analysis. The paper focuses on determining whether transformational leadership or transactional leadership is effective as shown by the levels of empowerment derived from these two types of leadership under study. As a result, both the Moderated Regression Multiple analysis and structural equation model searched information on transformational and followership for empowerment having moderating effects. In the Moderated Regression Multiple analysis, results showed that empowerment for leadership in business in the regulation of followership role appeared not to be seen. However, using the structural equation modeling, moderating effects have been found.

Consideration of the Structural Strength of High Speed Aluminum Planning Boat Plate Member (고속 경구조선 알루미늄 판부재의 구조강도 고찰)

  • Ham, Juh-Hyeok
    • Journal of Ocean Engineering and Technology
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    • v.22 no.2
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    • pp.91-98
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    • 2008
  • In order to establish a design guide for the bottom plate structure of a 4.3 ton aluminum planning boat, the feasibilities of bottom plate scantling of the ship are investigated based on the results of structural strength analysis and a simple equation and evaluation system are developed for initial structural design purposes. This study consists of 5 steps: First, the background, necessity, and purpose of this study are explained briefly, Second, the principal dimensions of this ship, the position of the considered bottom plate members and material characteristics are introduced. Third, the equivalent design pressure concept is introduced and evaluated based on experience and experimental data. Fourth, the strength of bottom plate members are examined using elasto-plastic nonlinear structural analysis, and response levels and several boundary conditions are reviewed based on the analysis results. Finally, in order to suggest design guides in respect to the ship's structural design, a simple design equation and evaluation system for bottom plate members are suggested for boats in the 4.3 ton aluminumboat range through the introduction of safety factorsbased on the ultimate design pressure concept.

An Importance-Performance Analysis(IPA) for Bus Users Travel Time by Using Structural Equation Model(SEM) (구조방정식모형(SEM)을 활용한 버스 이용자의 통행시간 중요도-만족도 분석(IPA))

  • Ahn, Woo-Young;Lee, Sol
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.3
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    • pp.663-670
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    • 2015
  • In most public transportation related master plans, decisions for investment priorities are initially made by facilities with lower installation rates or lower satisfaction (performance) levels. In general, the decisions are made without conducting importance factor analysis. In this study, a combined method of importance-performance analysis (IPA) model for bus users related in travel time is proposed by using Structural Equation Model (SEM). The results of the IPA for Metropolitan users show that the categories need improvement are number of bus stops, number of intersections, headways, waiting times for boarding and traffic signal operations in order. On the other hand, Non-Metropolitan uses show that the categories need improvement are traffic signal operations, waiting times for boarding, headways, bus exclusive lanes and number of intersections that is in reverse order to Metropolitan users.

The Causations among Leisure Constraints, Leisure Motivation, and Leisure Participation on the Ecological Perspective - Through the Construction of a Structural Equation Model (생태학적 관점에서 본 여가제약, 여가동기, 여가참여의 관계 -구조방정식 모형 구축을 통해)

  • Lee Yu-Ri;Park Mee-Sok
    • Journal of Families and Better Life
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    • v.24 no.1 s.79
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    • pp.11-30
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    • 2006
  • The purpose of this study was to verify a Structural Equation Model that constructed the causations among the leisure constraints, leisure. motivation, and leisure participation. This model posits that constraints determine motivation to participation. Concretely, structural and interpersonal leisure constraints(contextual factors) will affect interpersonal leisure constraints in the light of ecological perspective. Also, leisure constraints will affect leisure motivation based on self-determination theory that may influence leisure participation indirectly. A survey questionnaire was administered to 301 elderly in an institution for the elderly. A measurement model and a structural equation model estimates by Maximum Likelihood method(ML method) utilizing LISREL 8.0 ver. The analysis showed that a goodness of fit is good of structural equation model presented in the study. And, all hypothesis adopted about causations among the leisure constraints, leisure motivation, leisure participation.

Structural optimal control based on explicit time-domain method

  • Taicong Chen;Houzuo Guo;Cheng Su
    • Structural Engineering and Mechanics
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    • v.85 no.5
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    • pp.607-620
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    • 2023
  • The classical optimal control (COC) method has been widely used for linear quadratic regulator (LQR) problems of structural control. However, the equation of motion of the structure is incorporated into the optimization model as the constraint condition for the LQR problem, which needs to be solved through the Riccati equation under certain assumptions. In this study, an explicit optimal control (EOC) method is proposed based on the explicit time-domain method (ETDM). By use of the explicit formulation of structural responses, the LQR problem with the constraint of equation of motion can be transformed into an unconstrained optimization problem, and therefore the control law can be derived directly without solving the Riccati equation. To further optimize the weighting parameters adopted in the control law using the gradient-based optimization algorithm, the sensitivities of structural responses and control forces with respect to the weighting parameters are derived analytically based on the explicit expressions of dynamic responses of the controlled structure. Two numerical examples are investigated to demonstrate the feasibility of the EOC method and the optimization scheme for weighting parameters involved in the control law.

New fuzzy method in choosing Ground Motion Prediction Equation (GMPE) in probabilistic seismic hazard analysis

  • Mahmoudi, Mostafa;Shayanfar, MohsenAli;Barkhordari, Mohammad Ali;Jahani, Ehsan
    • Earthquakes and Structures
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    • v.10 no.2
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    • pp.389-408
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    • 2016
  • Recently, seismic hazard analysis has become a very significant issue. New systems and available data have been also developed that could help scientists to explain the earthquakes phenomena and its physics. Scientists have begun to accept the role of uncertainty in earthquake issues and seismic hazard analysis. However, handling the existing uncertainty is still an important problem and lack of data causes difficulties in precisely quantifying uncertainty. Ground Motion Prediction Equation (GMPE) values are usually obtained in a statistical method: regression analysis. Each of these GMPEs uses the preliminary data of the selected earthquake. In this paper, a new fuzzy method was proposed to select suitable GMPE at every intensity (earthquake magnitude) and distance (site distance to fault) according to preliminary data aggregation in their area using ${\alpha}$ cut. The results showed that the use of this method as a GMPE could make a significant difference in probabilistic seismic hazard analysis (PSHA) results instead of selecting one equation or using logic tree. Also, a practical example of this new method was described in Iran as one of the world's earthquake-prone areas.

A Study on the Structural Relationship between Authenticity of Sportswear Brand Corporate, Brand Image, Brand Attitude, and Premium Payment Intention

  • Jeon, Yong-Bae;Kim, Mi-Jeong
    • International journal of advanced smart convergence
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    • v.11 no.4
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    • pp.155-162
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    • 2022
  • The purpose of this study is to conduct an empirical study on brand authenticity targeting sportswear brand consumers. Through this, we intend to provide the accumulation and implications of authenticity research. For the research model, first, the authenticity of sportswear brand companies was selected as an independent variable. Brand image and brand attitude were selected as the next parameters. Finally, the dependent variable was the intention to pay the premium. Structural equation model analysis was conducted for the structural relationship between these variables. The subjects of this study are consumers who have purchased sportswear brands within the past year. Convenience sampling was used for the sample survey, and 262 people were finally selected as valid samples. The survey was conducted as a non-face-to-face online survey due to the COVID-19 infection. For data processing, frequency analysis was conducted using SPSS 23 to identify the individual characteristics of the survey subjects. In addition, exploratory factor analysis and reliability analysis were performed to refine the scale of the survey tool. Next, using AMOS 21, confirmatory factor analysis and correlation analysis were conducted to verify the measurement model. In addition, structural equation model analysis was conducted to verify the hypothesis. As a result of the analysis, all six hypotheses selected from the research model were adopted.

A dynamical stochastic finite element method based on the moment equation approach for the analysis of linear and nonlinear uncertain structures

  • Falsone, Giovanni;Ferro, Gabriele
    • Structural Engineering and Mechanics
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    • v.23 no.6
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    • pp.599-613
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    • 2006
  • A method for the dynamical analysis of FE discretized uncertain linear and nonlinear structures is presented. This method is based on the moment equation approach, for which the differential equations governing the response first and second-order statistical moments must be solved. It is shown that they require the cross-moments between the response and the random variables characterizing the structural uncertainties, whose governing equations determine an infinite hierarchy. As a consequence, a closure scheme must be applied even if the structure is linear. In this sense the proposed approach is approximated even for the linear system. For nonlinear systems the closure schemes are also necessary in order to treat the nonlinearities. The complete set of equations obtained by this procedure is shown to be linear if the structure is linear. The application of this procedure to some simple examples has shown its high level of accuracy, if compared with other classical approaches, such as the perturbation method, even for low levels of closures.

Development of a Numerical Method for Effective Elastic Analysis of Unbounded Solids with Anisotropic Inclusions (이방성 함유체가 포함된 무한고체의 효과적인 탄성해석을 위한 수치해석 방법 개발)

  • 최성준;이정기
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.04a
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    • pp.41-52
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    • 1998
  • A volume integral equation method and a mixed volume and boundary integral equation method are presented for the solution of plane elastostatic problems in solids containing orthotropic inclusions and voids. The detailed analysis of the displacement and stress fields are developed for orthotropic cylindrical and elliptic-cylindrical inclusions and voids. The accuracy and effectiveness of the new methods are examined through comparison with results obtained from analytical and boundary integral equation methods. Through the analysis of plane elastostatic problems in unbounded isotropic matrix containing orthotropic inclusions and voids, it is established that these new methods are very accurate and effective for solving plane elastostatic and elastodynamic problems in unbounded solids containing general anisotropic inclusions and voids or cracks.

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A Study on Optimum Modification of Dynamic Characteristics of Stiffened Plate Using Simplified Equation of Natural Frequency (고유진동수의 간이 추정식을 이용한 보강판 구조물의 동특성의 최적변경에 관한 연구)

  • 박성현;남정길
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.1
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    • pp.48-58
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    • 2002
  • There is a purpose of this study for the proposal of the optimum technique utilized for the vibration design initial step. The stiffened plate structure for the ship hull is made for analysis model. To begin with, dynamic characteristics of stiffened plate structure is analysed using FEM. Main vibrational mode of the structure is decided in the analytical result of FEM. The simplified equation on the natural frequency of the main vibrational mode is induced. Next, sensitivity analysis is carried out using the simplified equation, and rate of change of dynamic characteristics is calculated. Then, amount of design variable is calculated using this sensitivity value and optimum structural modification method. The change of natural frequency is made to be an objective function. Thickness of panel, cross section moment of stiffener and girder become a design variable. The validity of the optimization method using simplified equation is examined. It is shown that the result effective in the optimum modification for natural frequency of the stiffened plate structure.