• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.892-896
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• 2001

Investigation is performed on the stability of nonlinear system under turbulent fluid motion modelled as white noise random process, which is a preliminary result in the course of research on the characteristic and nonlinear control of the stochastic system. Adopted physical model is beam-type structure with tip-mass and main base mass. The governing equation is derived via F-P-K approach in stochastic sense. By means of Gaussian Closure method infinite dynamic moment equations due to system nonlinearity is closed to finite one. At the best of authors' knowledge, it is the first trial to design nonlinear controller by using of sliding mode technique in stochastic domain and control performance and effect in stochastic domain is studied.

• Korean journal of food and cookery science
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• v.22 no.2 s.92
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• pp.213-221
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• 2006

Although motivation and information search have both been studied continuously and separately as important marketing strategies, the relation between cause and effect has received little research attention. Therefore the objective of this study was to research the causal relationships between motivation and information search method. Frequency analysis and reliability analysis, factor analysis, and SEM(Structure Equation Model) were adopted to analyze the data. Motivation was divided into 5 factors which significantly influenced information search method. Factor 1, 'Reception and congratulation', influenced information search positively through 'newspaper, magazine', and 'word of mouth' but negatively through 'TV-advertising' and 'Flyer, Press copy'. Factor 2, 'Change of dietary life', influenced positively 'TV-advertising'. Factor 3, 'Economic saving', influenced positively 'newspaper, magazine', and 'the e-mail's advertising' Factor 4, 'Preference motivation', influenced negatively 'word of mouth' Factor 5, 'Advertisement and companion's need', influenced positively 'newspaper, magazine', and 'the e-mail's advertising' but negatively 'TV-advertising' As a result, customers appeared to choose various information search methods according to their eating-out motivation. 'The e-mail's advertising', and 'word of mouth' are popular among customers' information search methods. Therefore, food-service corporations need to try eliminating negative images of various advertisements and activate positive word of mouth marketing, promotion through internet.

• Smart Structures and Systems
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• v.18 no.4
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• pp.787-800
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• 2016

The aim of the paper is to analyze nonlinear transverse vibration of an embedded piezoelectric plate reinforced with single walled carbon nanotubes (SWCNTs). The system in rested in a Pasternak foundation. The micro-electro-mechanical model is employed to calculate mechanical and electrical properties of nanocomposite. Using nonlinear strain-displacement relations and considering charge equation for coupling between electrical and mechanical fields, the motion equations are derived based on energy method and Hamilton's principle. These equations can't be solved analytically due to their nonlinear terms. Hence, differential quadrature method (DQM) is employed to solve the governing differential equations for the case when all four ends are clamped supported and free electrical boundary condition. The influences of the elastic medium, volume fraction and orientation angle of the SWCNTs reinforcement and aspect ratio are shown on frequency of structure. The results indicate that with increasing volume fraction of SWCNTs, the frequency increases. This study might be useful for the design and smart control of nano/micro devices such as MEMS and NEMS.

• Asia-Pacific Journal of Business
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• v.9 no.2
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• pp.39-57
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• 2018

As competition grows in the telecommunication service industry, understanding the origins of brand image and consumer behavioral intentions challenges practitioners to design an effective marketing strategy and branding plan. In this paper, brand image and behavioral relationships are investigated in Bangladesh, an emerging market that has a particular socio-cultural and economic context of one of the most densely populated countries of South Asia. This study employs confirmatory factor analysis and structural equation modeling to analyze the database. Empirical testing and the proposed model suggest that brand image is the prime determinant of consumer satisfaction and loyalty. The results highlight the importance of perceived value, perceived trust and price structure to project brand image and satisfaction. Additionally, confirmation exhibits a stronger total effect of brand image on customer loyalty. Empirical findings extensively contribute to the theoretical and managerial understanding of subscribers' attitudes toward telecommunication service in an emerging market context.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1210-1215
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• 2000

Investigation is performed on the stability of general form of dynamic system under colored noise random disturbance whose damping and stiffness are varying in irregular manner along time, which is a preliminary result in the course of research on the characteristic and the control of the stochastic system. Adopted physical model is airfoil under random atmospheric disturbance, which becomes a "time-varying system" whose the governing equation is derived via F-P-K approach in stochastic sense. Control performance and effect of 'Heo-stochastic controller for colored noise' is studied. Also stochastic feature of flutter boundary is discussed as well.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.797-808
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• 2014

It is increasingly interested in investigating the relationships and the dynamic characteristics of variations among high class corporate values. This study formulates a statistical model of simultaneous equation system to examine the relationships among variations of stock returns for each class of corporate governance structure and to analyze the dynamic patterns of their long-run adjustment processes. Changes in stock returns for each class of corporate governance by an exogenous shock are found to have common structural features of slow adjustments to the long-run equilibriums.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.3
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• pp.8-16
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• 2006

This paper discusses design sensitivity analysis and its application to a structural dynamics modification. Eigenvalue derivatives are determined with respect to the element parameters, which include intrinsic property parameters such as Young's modulus, density of the material, diameter of a beam element, thickness of a plate element, and shape parameters. Derivatives of stiffness and mass matrices are directly calculated by derivatives of element matrices. The first and the second order derivatives of the eigenvalues are then mathematically derived from a dynamic equation of motion of FEM model. The calculation of the second order eigenvalue derivative requires the sensitivity of its corresponding eigenvector, which are developed by Nelson's direct approach. The modified eigenvalue of the structure is then evaluated by the Taylor series expansion with the first and the second derivatives of eigenvalue. Numerical examples for simple beam and plate are presented. First, eigenvalues of the structural system are numerically calculated. Second, the sensitivities of eigenvalues are then evaluated with respect to the element intrinsic parameters. The most effective parameter is determined by comparing sensitivities. Finally, we predict the modified eigenvalue by Taylor series expansion with the derivatives of eigenvalue for single parameter or multi parameters. The examples illustrate the effectiveness of the eigenvalue sensitivity analysis for the optimization of the structures.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.835-837
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• 2012

In this paper, we have been analyzed conduction path by device parameter of double gate(DG) structure that have top gate and bottom gate. The Possion equation is used to analytical. The change of conduction path have been investigated for various channel lengths, channel thickness and gate oxide thickness using this model, given that these parameters are very important in design of DGMOSFET. The optimum channel doping concentration is determined as the deviation of conduction path is considered according to channel doping concentration.

• Journal of Korean Society for Quality Management
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• v.44 no.4
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• pp.983-997
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• 2016

Purpose: The purpose of this paper is to examine the structural relationship among leader-member exchange(LMX), empowerment, job satisfaction, organizational commitment, and customer orientation in a low-cost carrier industry. Methods: The collected data through the survey were analyzed using structure equation model analysis The sample used for the empirical analysis is a total of 231 questionnaires. Results: The results of empirical analysis are summarized as follows. First, LMX in a low-cost airline has a significant effect on empowerment, job satisfaction, and customer orientation Second, empowerment has a significant impact on organizational commitment and job satisfaction. However, it is not significantly related to customer orientation. Third, Organization Commitment has significant effect on jon satisfaction. Finally, job satisfaction has a significant impact on customer orientation. Conclusion: This paper has a contribution in that it extends the range of the academic research concerning LMX. Also this paper provides implications on effective human resource management method suitable for a Jeju-Air.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.8
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• pp.186-192
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• 1999

This paper introduces a study of a method for the forward kinematic analysis, which finds the 6 DOF motions and velocities from the given six cylinder lengths in the Stewart platform. From the viewpoints of kinematics, the solution for the inverse kinematic is easily found by using the vectors of the links which are composed of the joint coordinates in base and plate frames, to act contrary to the serial manipulator, but forward kinematic is difficult because of the nonlinearity and complexity of the Stewart platform dynamic equation with the multi-solutions. Hence we, first in this study, introduce the linear estimator using the Luenberger's observer, and the estimator using the nonlinear measured model for the forward kinematic solutions. But it is difficult to find the parameter of the design for the estimation gain or to select the estimation gain and the constant steady state error exists. So this study suggests the estimator with the estimation gain to be learned by the neural network with the structure of multi-perceptron and the learning method using back propagation and shows the estimation performance using the simulation.