• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.399-406
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• 1998

An investigation into the stochastic bifurcation and response statistits of an autoparameteric system under broad-band random excitation is made. The specific system examined is a spring-pendulum system with internal resonance, which is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. The Fokker-Planck equations is used to generate a general first-order differential equation in the dynamic moment of response coordinates. By means of the Gaussian and non-Gaussian closure methods the dynamic moment equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. In view of equilibrium solutions of this system and their stability we examine the stochastic bifurcation and response statistics. The analytical results are compared with results obtained by Monte Carlo simulation.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.175-181
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• 2001

An investigation into the response statistics of a spring-pendulum system whose base oscillates randomly along vertical and horizontal line is made. The spring-pendulum system with internal resonance examined is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. The Fokker-Planck equation is used to generate a general first-order differential equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. In view of equilibrium solutions of this system and their stability, the response statistics is examined. It is seen that increase in horizontal excitation level leads to a decreased width of the internal resonance region.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.86-94
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• 1997

An investigation into the modal interaction of an autoparametric system under broad-band random excitation is made. The specific system examined is a spring-pendulum system with internal resonance, which is known to be a good model for a variety of engineering systems, including ship motions with nonlinear coupling between pitching and rolling motions. By means of the Gaussian closure method the dynamic moment equations explaining the random response of the system are reduced to a system of autonomous ordinanary differential equations of the first and second moments. In view of equilibrium solutions of this system and their stability we examine the system responses. The stabilizing effect of system damping is also examined.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.2
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• pp.133-139
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• 2001

The nonlinear response statistics of an spring-pendulum system with internal resonance under narrow band random excitation is investigated analytically- The center frequency of the filtered excitation is selected to be close to natural frequency of directly excited spring mode. The Fokker-Planck equations is used to generate a general first-order differential equation in the dynamic moment of response coordinates. By means of the Gaussian closure method the dynamic moment equations for the random responses of the system are reduced to a system of autonomous ordinary differential equations. The nonlinear phenomena, such as jump and multiple solutions, under narrow band random excitation were found by Gaussian closure method.

• Structural Engineering and Mechanics
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• v.45 no.3
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• pp.373-389
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• 2013

This paper presents the influence of incident angles of earthquakes on inelastic dynamic responses of asymmetry single story buildings under seismic ground motions. The dynamic responses such as internal forces and rotational ductility factor are used to evaluate the importance of the incident angles of ground motions in the inelastic range of structural behavior. The base shear and torque (BST) response histories of the resisting elements and of the building are used to prove that the shape of the BST surface of the building can be a practical tool to represent those of all resisting elements. This paper also shows that the different global forces which produce the maximum demands in the resisting elements tend to converge toward a single distribution in a definable intensity range, and this single distribution is related to the resistance distribution of the building.

• 한국경영정보학회:학술대회논문집
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• 2007.06a
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• pp.690-698
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• 2007

By investigating Internet shopping malls from a viewpoint ofenvironmental psychology, this study tries to expand the subject of servicescape into the Internet rather than to confine it to physical space. This study empirically validates the effect of e-servicescape (hereinafter e-scape) on customers' cognitive and emotional responses which subsequently can lead to customers' behaviors. An analysis of 490 questionnaires found that e-scape influences the emotional and cognitive responses, ultimately triggering customers' behaviors. We also found that the effects of e-scape on customers' behavior may be mediated by customers' internal responses. Based on the analysis result, servicescape management is important on the Internet just as it is in physical space. Concepts such as e-scape management can be one of the effective strategies to make an Internet shopping mall distinguishable from other Internet shopping malls.

• Earthquakes and Structures
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• v.22 no.5
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• pp.517-526
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• 2022

In this paper, nonlinear P-delta effects are studied on the seismic performance, and the modal responses of a flexural frame, considering large deformations. Using multiple scales method, the nonlinear differential equations of motion are estimated, and the nonlinear interactions between the frame's degrees of freedom are outcropped. The results of time and frequency domain analyzes of a dynamic model are examined under internal resonance cases, and the linear and nonlinear responses are investigated in each modal cases. Also, changing the modal responses with respect to the amplitude and frequency of the harmonic forces is evaluated. It is shown that the dominant absorption of energy is in the first natural frequency of the frame, in the case of earthquake excitation, and when a harmonic force is applied to the frame, the peaks of the frequency domain responses depending on the frequency of harmonic force are in the first, and second or third natural frequency of the structure.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.11
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• pp.2098-2110
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• 1992

An analysis is presented for the combination resonance of a clamped circular plate, which occurs when the frequency of the excitation is near the combination of the natural frequencies, that is, when ohm.=2.0mega.／sub 1／+omega.／sub 2／. The internal resonance, Omega.／sub 3／=omega.／sub 1／+2.omega.／sub 2／, is considered and its influence on the response is studied. The clamped circular plate experiencing mid-plane stretching is governed by a nonlinear partial differential equation. By using Galerkin's method the governing equation is reduced to a system of nonautonomous ordinary differential equations. The method of multiple scales is used to obtain steady-state responses of the system. Results of numerical investigations show that the increase of the excitation amplitude can reduce the amplitudes of steady-state responses. We can not find this kind of results in linear systems.

• Journal of Ginseng Research
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• v.32 no.3
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• pp.250-256
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• 2008

Red ginseng is a medicinal herb widely used in East-Asia for a long time. Recently there have been a lot of studies about the effect of red ginseng on the immune responses. We investigated the differences between Korean red ginseng and Chinese red ginseng in the lymphocyte proliferation and cytokine production. The rats were divided into 3 groups, KRG(Korean Red Ginseng) group, CRG(Chinese Red Ginseng) group, and the Control group. Experimental groups were administered with Korean and Chinese red ginsengs for three months respectively. Then we obtained the lymphatic cells from spleen and compared the ability of KRG on the lymphocyte proliferation and the cytokine production after mitogen-stimulated culture to CRG. The proliferation of lymphocyte and level of $IL-1{\alpha}$ were significantly increased only in KRG group. There were significant increases in the level of $INF-{\gamma}$ in both KRG and CRG groups. There were no significant differences in the level of IL-2 and $TNF-{\alpha}$. These results indicate that KRG can induce infection-relevant immune responses much faster and higher than CRG. Furthermore, functional activation of CD8+ T-cell may be activated by red ginsengs.

• Human Ecology Research
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• v.59 no.3
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• pp.311-324
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• 2021

The purpose of this study was to reveal the effects of internal characteristics, such as fashion involvement, personality characteristics, and customer orientation of fashion brand salespeople on the core sales tasks, and how the core sales tasks and internal characteristics differ depending on differences in the way salespeople are remunerated. The data were collected as a questionnaire to fashion brand salespeople in Gwangju from September to October 2020. Using 235 responses, the data were analyzed with SPSS 21.0 for frequency analysis, reliability analysis, t-test, factor analysis, and regression analysis. The research results were as follows. First, fashion involvement comprises factors such as 'fashion passion and sense'and 'fashion trend interest', and the greater the 'fashion passion and sense', the better the 'sales management'and 'customer relationship management'jobs. Second, 'esthetic openness', 'responsibility' and 'extroversion' of the big five personality characteristics have a positive impact on 'sales management' and 'customer relationship management' tasks. Third, customer orientation comprises factors such as 'customer-centric understanding'and 'gain customer trust', the greater the customer-orientation, the better the 'sales management'and 'customer relationship management'tasks. Fourth, according to the position of the salesperson, the group of professional salespeople at manager level had high responses in core sales tasks, fashion involvement, customer orientation, and characteristics such as 'agreeableness', 'esthetic openness', and 'responsibility'.