• Computational Structural Engineering
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• v.3 no.4
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• pp.113-122
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• 1990

An analytical simulation of the flexural behavior of SFRC beam has been illustrated. Curvature distributions and crack opening in critical region were taken into account. Compressive and tensile constitutive models which express post-peak behavior of SFRC with stress-crack opening relationships were incorporated in simulating nonlinear flexural behavior of the beam. The model was able to predict test results with reasonable accuracy. Behavior of the critical section and effects of different factors m the flexural behavior of SFRC beam were investigated. Simple observation and statistical approach have been made in selecting most influential parameters in flexural behavior of SFRC.

• Bulletin of the Korean Chemical Society
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• v.10 no.4
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• pp.372-374
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• 1989

The new viscosity theory is applied to the abnormal behavior of the viscosity near the critical point. This theory suggests that the viscosity is equal to the product of the absolute pressure(kinetic pressure + internal pressure) and the collision time. We can find this abnormal behavior to be due to the large collision time near the critical point. The agreements between theoriticals and experimentals of the critical enhancement are satisfactory.

• Journal of the Korean Mathematical Society
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• v.58 no.3
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• pp.723-740
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• 2021

Design and maintenance of large span roof structures require an analysis of their static and dynamic behavior depending on the physical parameters defining the structures. Therefore, it is highly desirable to estimate the parameters from observations of the system. In this paper we study the parameter estimation problem for damped shallow arches. We discuss both symmetric and non-symmetric shapes and loads, and provide theoretical and numerical studies of the model behavior. Our study of the behavior of such structures shows that it is greatly affected by the existence of critical parameters. A small change in such parameters causes a significant change in the model behavior. The presence of the critical parameters makes it challenging to obtain good estimation. We overcome this difficulty by presenting the Parameter Estimation Algorithm that identifies the unknown parameters sequentially. It is shown numerically that the algorithm achieves a successful parameter estimation for models defined by arbitrary parameters, including the critical ones.

• Asia pacific journal of information systems
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• v.9 no.4
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• pp.125-142
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• 1999

The increased investment in technological innovations makes the investigation of factors affecting technology adoption more interesting. Several perspectives have been proposed to explain the determinants of information technology adoption. While the traditional innovation diffusion research streams try to explain and predict adoption behavior with the adopter's perceptions about the characteristics of the innovation itself, critical mass theorists argue that adoption behavior as a collective action is based on what their business partners are doing and whether there exists enough critical mass to justify the investment. Drawing on theses two perspectives, this study investigates the decision criteria in the adoption of information technology as innovation and factors affecting the decision criteria. The survey results reveal that the adoption behavior is affected both by innovation characteristics and by critical mass's activity. Correlation analysis, t-test, and stepwise regression models also show that as the environmental uncertainty is getting higher, adoption decision is affected more by what others are doing, and that highly competitive organizations seem to play the role of critical mass.

• Journal of the Korean Statistical Society
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• v.25 no.4
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• pp.515-527
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• 1996

It has been known for mean field models that the limiting distribution reflecting the asymptotic behavior of the system is non-Gaussian at the critical state. Recently, however, Papangelow showed for the critical Curie-Weiss mean field model that there exist Gaussian structures in the asymptotic behavior of the total magnetization. We construct Gaussian structures existing in the internal fluctuation of the system for the critical case of a generalized Curie-Weiss mean field model.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.462-473
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• 2019

This study examined the evidence on how self-leadership and career decision-making self-efficacy scale can produce a mediating effect on the relation between critical thinking disposition and career preparation behavior of nursing students. The subjects were college students majoring in nursing in Gwangju. The data collected was for 263 such students. It was analyzed with SPSS 23.0 for windows. To examine the mediating effect, the study used Sobel. The findings were as follows. First, critical thinking disposition positively influences career preparation behavior of nursing students. Secondly, self-leadership and career decision-making self-efficacy show a complete mediating effect on the relation between critical thinking disposition and career preparation behavior in nursing students. These findings suggest that in order to promote career preparation behavior of nursing students, educational programs should improve subjects on critical thinking disposition. It also suggests self-leadership and career decision self-efficacy should be provided in nursing education field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.505-516
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• 2018

The purpose of the present study was to examine the mediating effect of self-concealment on the relationship between self-critical perfectionism and disordered eating behavior. Toward this aim, 348 participants responded to the measures of self-critical perfectionism, self-concealment and disordered eating behavior. Correlation analysis revealed that self-critical perfectionism was positively correlated with self-concealment and disordered eating behavior. In addition, self-concealment was positively correlated with disordered eating behavior. Structural equations analysis found that the relationship between self-critical perfectionism and disordered eating behavior had a significant partial mediating effect on self-concealment, meaning that self-critical perfectionism increased disordered eating behavior through high levels of self-concealment. This finding suggests that individuals who place high standards on themselves, and feature fear of negative evaluation from others, are at greater risk for disordered eating behavior. Based on this finding, we discussed suggestions for future research and clinical implications.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1756-1766
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• 2003

Numerical modeling is carried out to investigate forced convective heat transfer to near-critical water in developing laminar flow through a circular tube. Due to large variations of thermo-physical properties such as density, specific heat, viscosity, and thermal conductivity near thermodynamic critical point, heat transfer characteristics show quite different behavior compared with pure forced convection. With flow acceleration along the tube unusual behavior of heat transfer coefficient and friction factor occurs when the fluid enthalpy passes through pseudocritical point of pressure in the tube. There is also a transition behavior from liquid-like phase to gas-like phase in the developing region. Numerical results with constant heat flux boundary conditions are obtained for reduced pressures from 1.09 to 1.99. Graphical results for velocity, temperature, and heat transfer coefficient with Stanton number are presented and analyzed.

• Journal of Magnetics
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• v.19 no.4
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• pp.315-322
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• 2014

In this work, Artificial Neural Network (ANN) was used to model the dynamic behavior of ferromagnetic hysteresis derived from performing the mean-field analysis on the Ising model. The effect of field parameters and system structure (via coordination number) on dynamic critical points was elucidated. The Ising magnetization equation was drawn from mean-field picture where the steady hysteresis loops were extracted, and series of the dynamic critical points for constructing dynamic phase-diagram were depicted. From the dynamic critical points, the field parameters and the coordination number were treated as inputs whereas the dynamic critical temperature was considered as the output of the ANN. The input-output datasets were divided into training, validating and testing datasets. The number of neurons in hidden layer was varied in structuring ANN network with highest accuracy. The network was then used to predict dynamic critical points of the untrained input. The predicted and the targeted outputs were found to match well over an extensive range even for systems with different structures and field parameters. This therefore confirms the ANN capabilities and indicates the ANN ability in modeling the ferromagnetic dynamic hysteresis behavior for establishing the dynamic-phase-diagram.

• Journal of Korean Association for Spatial Structures
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• v.20 no.4
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• pp.149-158
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• 2020

The governing equation for a dome-type shallow spatial truss subjected to a transverse load is expressed in the form of the Duffing equation, and it can be derived by considering geometrical non-linearity. When this model under constant load exceeds the critical level, unstable behavior is appeared. This phenomenon changes sensitively as the number of free-nodes increases or depends on the imperfection of the system. When the load is a periodic function, more complex behavior and low critical levels can be expected. Thus, the dynamic unstable behavior and the change in the critical point of the 3-free-nodes space truss system were analyzed in this work. The 4-th order Runge-Kutta method was used in the system analysis, while the change in the frequency domain was analyzed through FFT. The sinusoidal wave and the beating wave were utilized as the periodic load function. This unstable situation was observed by the case when all nodes had same load vector as well as by the case that the load vector had slight difference. The results showed the critical buckling level of the periodic load was lower than that of the constant load. The value is greatly influenced by the period of the load, while a lower critical point was observed when it was closer to the natural frequency in the case of a linear system. The beating wave, which is attributed to the interference of the two frequencies, exhibits slightly more behavior than the sinusoidal wave. And the changing of critical level could be observed even with slight changes in the load vector.