• Journal of the Society of Naval Architects of Korea
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• v.45 no.6
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• pp.735-749
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• 2008

For the development of the original technique of structural safety assessment of Cargo Containment System(CCS) in membrane type LNG carriers, it is necessary to understand the characteristics of dynamic response behavior of CCS structure under sloshing impact pressure. In the previous study, the wet drop impact response analyses of CCS structure in membrane Mark III type LNG carriers were carried out by using Fluid-Structure Interaction(FSI) analysis technique of LS-DYNA code, and were also validated through a series of wet drop experiments for the enhancement of more accurate shock response analysis technique. In this study, the characteristics of structural shock response behaviors of CCS structure were sufficiently figured out by careful examinations of the effects of specimen weight, drop height, incident angle, corrugation and stiffness of inner hull on its shock response behaviors. The shock response analysis of upward shooting fluid to inner hull was performed, and the reason of faster strain response than shock pressure one was also figured out.

• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.44-56
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• 1993

The purpose of this paper is to analyze the impact response behaviors of glass/epoxy laminated composite plates subjected to the transversely impact of a steel ball. For this purpose, dynamic finite element analysis based on the higher-order shear defomation plate theory is used to compute the contact forces, rebound velocity of a steel ball, and dynamic strain response histories. And low-velocity and high-velocity impact experiments were conducted to compare the results and compute the wave propagation velocities. The results obtained from impact experiments are in good agreement with those of dynamic finite element analysis. Also the wave propagation velocities obtained from high-velocity impact experiments and wave propagation theory agree well, and wave velocities were higher in the smaller radius of steel ball.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.6
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• pp.726-734
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• 2008

While the structural safety assessment of Cargo Containment System(CCS) in membrane type LNG carriers has to be carried out in consideration of sloshing impact pressure, it is very difficult to figure out its dynamic response behaviors due to its very complex structural arrangements/materials and complicated phenomena of sloshing impact loading. For the development of its original technique, it is necessary to understand the characteristics of dynamic response behavior of CCS structure under sloshing impact pressure. In this study, for the exact understanding of dynamic response behavior of CCS structure in membrane Mark III type LNG carriers under sloshing impact pressure, its wet drop impact response analyses were carried out by using Fluid-Structure Interaction(FSI) analysis technique of LS-DYNA code, and were also validated through a series of wet drop experiments for the enhancement of more accurate shock response analysis technique. It might be thought that the structural response behaviors of impact response analysis, such as impact pressure impulses and resulted strain time histories, generally showed very good agreement with experimental ones with very appropriate use of FSI analysis technique of LS-DYNA code, finite element modeling and material properties of CCS structure, finite element modeling and equation of state(EOS) of fluid domain.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.5
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• pp.451-456
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• 2011

To ensure structural integrity of membrane type LNG tank, the rational assessment of the sloshing impact responses of tank structures should be preceded. The sloshing impact pressures acting on the insulation system of LNG tank are typical irregular loads and the resulting structural responses show very complex behaviors accompanied with fluid structure interaction. So it is not easy to estimate them accurately and immense time consuming calculation process would be necessary. In this research, a simplified method to analyse the dynamic structural responses of LNG tank insulation system under pressure time histories obtained by sloshing model test or numerical analysis was studied. The proposed technique based on the concept of linear combination of the triangular response functions which are the transient responses of structures under the unit triangular impact pressure acting on structures. The validity of suggested method was verified through the example calculations and applied to the dynamic structural response analysis of a real Mark III membrane type insulation system using the sloshing impact pressure time histories obtained by model test.

• Journal of the Korean Society of Safety
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• v.16 no.1
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• pp.9-17
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• 2001

The purpose of this research is to analyze the impact resposes(impulsive stress and strain etc.) of anisotropic materials subjected to the low-velocity impact. For this purpose, a beam finite element program based on modified higher-order beam theory for anisotropic materials are developed and used to simulate the dynamic behaviors [contact force, displacement of ball and target, strain(stress) response histories] according to the changes of material property, stacking sequence, velocity and dimension etc.. Test materials for simulation are composed of $[0^{\circ}/45^{\circ}/0^{\circ}/-45^{\circ}/0^{\circ}]_{2s} and [90^{\circ}/45^{\circ}/90^{\circ}/-45^{\circ}/90^{\circ}]_{2s}$ stacking sequences. Finally, the results of this simulation are compared with those of wave propagation theory and then the impact responses and wave propagation phenomena are investigated.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.885-890
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• 2007

Fast Fourier Transformation(FFT) is one of the most useful way to analyze response signal for the purpose of grasping the dynamic characteristics of system. Vibration test using impact hammer is typical and simple experimental method widely used for catching hold of dynamic peculiar characters and modal behaviors of system. In this thesis, impact testing module for NI-PXI equipment is developed. The analyzing and visualizing module are developed with LabVIEW tool. A user can see quickly and easily modal shape of system after analyzing acquired data. This developed module will be expected to build up more convenient and serviceable measurement system.

• Asia Marketing Journal
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• v.17 no.1
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• pp.1-26
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• 2015

In the 21^st century, green consumer behavior, playing one of the core roles of sustainability, is still an important issue to green-related stakeholders. Because one of the major objectives of green-consumer research is an improvement of behaviors aligned with greening, this paper revisited socio-demographic variables and shed light on segmenting and profiling green consumers based on their connectedness between socio-demographic variables and green behaviors. Using correlations, factor analysis, analysis of variance, k-means cluster analysis and χ²-tests, this paper shows that socio-demographic variables differentially impact green-consumer behaviors. In order to profile green consumers, this paper additionally attempts to segment green-consumer groups. The results also coincide with former findings that socio-demographic variables relate significantly with segmented green-consumer group behaviors. General findings are summarized as: 1) older people used green practices more strongly than younger people, 2) females demonstrated better energy-saving and recycling practices compared to males, 3) marital status also significantly influenced green-related behaviors, 4) subjective social class had a significant influence on green-related behaviors, 5) education level and income, however, weakly influenced or showed no impact on green-related behaviors, and 6) a green consumer was classified as an 'active green consumer,' 'utilitarian green consumer,' or 'inactivated green consumer.' The utilitarian green consumer group distinctively behaved more strongly in energy-saving and recycling practices compared to the inactivated green consumer group, whereas active green consumers behaved more strongly on the whole, when compared to those in the inactivated green consumer group.

• Korean Journal of Artificial Intelligence
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• v.12 no.2
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• pp.25-33
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• 2024

This study examines the relationship between customer satisfaction and management response in the hotel industry amid the COVID-19 pandemic. By applying regression analysis and topic modeling to consumer reviews on online platforms, we assess how consumer perceptions and management behaviors have shifted since the onset of the pandemic. The findings reveal a significant decline in customer satisfaction linked to COVID-19. Significantly, while the pandemic has reduced overall customer satisfaction levels, high response rates and high review-response content similarity mitigate the impact of the crises. These results highlight the critical need for hotel managers to continuously monitor online reviews and adapt their engagement strategies to maintain and enhance customer satisfaction during ongoing and future crises. This research not only corroborates existing theories on customer satisfaction but also exposes novel dynamics introduced by the pandemic, offering new insights for effective customer relationship management in turbulent times.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.531-538
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• 2011

To ensure the structural integrity of membrane type LNG tank, the rational assessment of impact pressure and structural responses due to sloshing should be preceded. The sloshing impact pressures acting on the insulation system of LNG tank are typical irregular loads and the structural responses caused by them also very complex behaviors including fluid structure interaction. So it is not easy to estimate them accurately and huge time consuming process would be necessary. In this research, a simplified method to analyze the dynamic structural responses of LNG tank insulation system under pressure time histories obtained by sloshing model test or numerical analysis was proposed. This technique basically based on the concept of linear combination of the triangular response functions which are obtained by the transient response analysis under the unit triangular impact pressure acting on structures in time domain. The validity of suggested method was verified through the example calculations and applied to the structural analysis of real Mark III type insulation system using the sloshing impact pressure time histories obtained by model test.

• Korean Journal of Human Ecology
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• v.23 no.6
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• pp.1141-1154
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• 2014

The purpose of this study examined the moderating effect of maternal emotion-related socialization behaviors on the relations between preschooler's effortful control and prosocial behavior. In this study, subjects were 153 preschoolers and their mothers. The major results were as follows; there was a moderating effect of maternal emotion-related socialization behaviors on the relationship between preschooler's effortful control and prosocial behavior. Specifically, maternal negative emotion expression and response to the preschooler's positive emotion moderated the effect preschooler's effortful control on prosocial behavior. In conclusion, the impact of effortful control on preschooler's prosocial behavior were significant. Also, maternal emotion-related socialization behaviors(i.e., negative emotion expression and response to the child's positive emotion) affected on preschooler's prosocial behavior. The findings of the study will contribute to help maternal emotional interaction with their preschool aged children.