• Structural Engineering and Mechanics
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• v.86 no.1
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• pp.49-68
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• 2023

This study investigates the static and dynamic structural analysis of symmetrical and asymmetrical coupled shear walls using the continuous and modified transfer matrix methods by idealizing the coupled shear wall as a three-field CTB-type replacement beam. The coupled shear wall is modeled as a continuous structure consisting of the parallel coupling of a Timoshenko beam in tension (with axial extensibility in the shear walls) and a shear beam (replacing the beam coupling effect between the shear walls). The variational method using the Hamilton principle is used to obtain the coupled differential equations and the boundary conditions associated with the model. Using the continuous method, closed-form analytical solutions to the differential equation for the coupled shear wall with uniform properties along the height are derived and a numerical solution using the modified transfer matrix is proposed to overcome the difficulty of coupled shear walls with non-uniform properties along height. The computational advantage of the modified transfer matrix method compared to the classical method is shown. The results of the numerical examples and the parametric analysis show that the proposed analytical and numerical model and method is accurate, reliable and involves reduced processing time for generalized static and dynamic structural analysis of coupled shear walls at a preliminary stage and can used as a verification method in the final stage of the project.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.103-109
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• 1995

The model foods were prepared by simulating mositure, protein and starch, and they were heated for 30 mins, at $80^{\circ}C$ and then cooled at $25^{\circ}C$ in water bath. Their rheological properties were investigated by the use of Brookfield wide-gap rotational viscometer at $30{\sim}60^{\circ}C$, and the rotation speed ranged from 0.6 to 6 rpm and solid content ranged from 8% to 11%, the results obtained were as follows. 1. All the model foods ($P_1S_3$, $P_2S_2$, $P_1S_1$, $P_2S_1$, $P_3S_1$, $P_4S_0$) exhibited pseudoplastic behaviors with yeild stress and were thixotropic foods which showed time - dependent structural decays, but the starch food of 8 ~ 11 % solid content did not show the flow behavior. 2. The correlation between the rheological parameters and the protein content of model foods in various moisture content did not appeared a constant relationship. 3. The change of shear stress against shear rate in high starch foods was larger than that in high protein foods and the structure at initial shear time was decayed with a quatic equation according to the Tiu's Model and structural decay was in parallel with the increase of shear rate. 4. The temperature dependency of the apparent viscosity of $P_1S_2$, and $P_2S_1$ was fully expressed by Arrhenius equation and activation energies of their food were 2.35 and $1.34Kcal/g{\cdot}mol$, respectively.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.423-431
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• 2009

The purpose of this study was verily the structure model of yacht participants' motives for sport participation, satisfactions of basic psychological need and intentions of persistent participation. Their motives for sport participation and satisfaction of basic psychological desires are reported as variables involving so much in their intentions of persistent participation in the sport activity in which participants of Life Exercise take part. Therefore, a survey research was conducted by aiming at members of yacht foyers' groups and university yacht clubs, 267 copies of the questionnaire in total were used for the analysis. SPSS 12.0 and AMOS 7.0 were used for the processing of the data, and exploratory factor analysis, confirmatory factor analysis, reliability analysis, correlation analysis and covariance structure model analysis were also applied according to each study objective. The results of the study were as follows: Firstly, there were significant correlations among yacht participants' satisfaction of basic psychological desires, participation motives and intentions of consistent participation. Secondly, yacht participants' satisfaction of basic psychological desires was found to have significant and direct effects on their intentions of persistent participation while haying indirect effects through the medium of their motives for sport participation at the same time. Thirdly, their motives for sport participation had significant effects on their intentions of persistent participation. Fourthly, suggested by the study, the structural equation model of yacht participants' motives for sport participation, satisfaction of basic psychological desires and intentions of persistent participation was found statistically appropriate.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.1
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• pp.45-52
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• 2009

In this paper, a guideline for designing breakwater in wave loads and in seismic loads is proposed. A simple model structure in breaking wave zone is examined using Morison equation in consideration with the effect of an impact load, for evaluation of the wave loads. As the impact load effect is not significant, pressure distributions according to Goda are applied for evaluation of wave loads on breakwater. Structural behavior of breakwater in wave loads can be obtained using the Goda method, as well. For seismic analysis, Ofunato and Hachinohe models, as well as an artificial seismic acceleration loads model, are adopted. Soil-structure interaction analysis is carried out to find the seismic load effect. It is found that, in certain cases, structural deformation in wave loads is in the same level as deformation that in seismic loads. Thus, it is our recommendation that these two loads are considered at the same level in breakwater design.

• Human Ecology Research
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• v.52 no.1
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• pp.43-53
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• 2014

The purpose of this study was to 1) investigate the characteristics of burnout of Korean elementary school students and 2) develop and validate the Korean Academic Burnout Scale-Elementary School Students (KABS-ESS). Fifty-one behavioral descriptions of burnout extracted through a preliminary survey, focus group interview, and literature review were administered to a sample of 531 elementary students of the 4th to 6th grade in Gyeonggi Province. The results of an exploratory factor analysis indicated that the structure of the burnout of Korean elementary school students consists of seven factors (i.e., inefficacy, avoidance, cynicism, emotional exhaustion, physical exhaustion, antipathy and cognitive exhaustion), and this structure of final 28 items was confirmed by the confirmatory factor analysis. The KABS-ESS showed a correlation of .771 with a representative academic burnout scale, Maslach Burnout Inventory-Student Survey, and -.561 with the academic engagement scale, indicating that both convergent and discriminant validities were confirmed. Furthermore, all fit indices of the structural equation model of the Schaufeli and Bakker's job demands-resources in an academic setting were satisfactory, and the possibility of the validity generalization of the model was supported. The demand variables predicting academic burnout and engagement were academic overload and parental pressure, while self-resilience, self-regulated learning strategies, and parental and the teacher's support were identified as the resource variables. Lastly, the implications and future direction of the present study were discussed.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.6
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• pp.511-518
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• 2013

To implement an automatic picking system (APS) in distribution center with high precision and high dynamics, this paper presents a design of a linear induction motor (LIM) drive and robust position controller based on integral variable structure control (IVSC) scheme. The force disturbance as well as the mechanical parameter variation such as the mass and friction coefficient gives a direct influence on the position control performance of APS. To guarantee a robust control performance in the presence of such uncertainty, a robust position controller is designed. A Simulink library is developed for the LIM model from the state equation. Through this model and comparative simulation based on Matlab - Simulink, it is proved that the proposed scheme has a robust control nature and is most suitable for APS.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.350-361
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• 2014

The purpose of this study was to find general trends in dental fear among adolescences at 15-17 years of age, differences in levels of dental fear according to relevant variables, and the degrees to which those variables influence fear of dental treatment and their causal relationships. The researcher made use of a questionnaire including tools of questionnaire survey DFS, DBS and questions regarding characteristics of adolescences, and then analyzed covariate structure modeling by using LISREL 8.12 after conducting univariate analysis by employing SPSS. Cronbach's reliability coefficients showed higher in DFS(0.957), DBS(0.916), and GFS(0.910). The more recent experience in pain in the oral cavity and the stronger pain when treating dental disease and the more frequent experience in pain when treating dental disease and also the more broken dental appointments, the higher levels of dental fear showed with statistical significance. The linear structure equation model was statistically appropriate and well fit. By the model, severity and frequency of pain during treatment, experience of breaking dental visit appointment, distrust for dentists and general fear were directly influenced on dental fear.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.869-872
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• 2006

In this paper, the threshold voltage roll-off been analyzed for nano structure double gate FinFET. The analytical current model has been developed , including thermionic current and tunneling current models. The potential distribution by Poisson equation and carrier distribution by Maxwell-Boltzman statistics are used to calculate thermionic emission current, and WKB(Wentzel- framers-Brillouin) approximation to tunneling current. The threshold voltage roll-offs are obtained by simple adding two currents since two current is independent. The threshold voltage roll-off by this model are compared with those by two dimensional simulation and two values are good agreement. Since the tunneling current increases especially under channel length of 10nm, the threshold voltage roll-off Is very large. The channel and gate oxide thickness have to be fabricated as thin as possible to decrease this short channel effects and this process has to be developed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.4
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• pp.760-765
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• 2007

In this paper, the threshold voltage roll-off and drain induced barrier lowering(DIBL) have been analyzed for nano structure double gate FinFET. The analytical current model has been developed, including thermionic current and tunneling current models. The potential distribution by Poisson equation and carrier distribution by Maxwell-Boltzman statistics were used to calculate thermionic omission current, and WKB(Wentzel- Kramers-Brillouin) approximation to tunneling current. The threshold voltage roll-offs are obtained by simple adding two currents since two current is independent. The threshold voltage roll-off by this model are compared with those by two dimensional simulation and two values are good agreement. Since the tunneling current increases especially under channel length of 10nm, the threshold voltage roll-off and DIBL are very large. The channel and gate oxide thickness have to be fabricated as thin as possible to decrease this short channel effects, and this process has to be developed.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.167-181
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• 2008

A pavement structure analysis model plays a very important role which can correlate input variables to performance models. In this research, a standard shell element model was developed by use of the ABAQUS program so that behaviors of concrete pavements be analyzed. The model was verified in terms of its accuracy by way of comparing the results to those gathered from closed-form Solutions, the Everfe program, and the ABAQUS program with a solid model. Many input variables were analyzed in the model, and the results were stored in a database. Based on the SPSS program, stress equations with respect to temperature and curling effects were developed. All models gave over 0.90 of R2 value except the case considering top-down curling (R2=0.86)