• Journal of Life Science
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• v.21 no.7
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• pp.1009-1015
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• 2011

Web structure of spiders is a foraging strategy as well as an investment to get prey. In order to increase the fitness consequence, spiders change their foraging strategy based on sensory information provided by prey species. We conducted an experiment to demonstrate whether an orb-web building spider, Argiope bruennichi modifies its web-building behavior after experiencing sensory information emitted by a UV recognizing flying insect, Bombus terrestris. To know how the web structure would be modified, we observed web characteristics after providing sensory information of a potential prey species, the bumblebee (experimental group) and compared them to the control group (no information provided). We hypothesized that the spiders of the experimental group would increase investments in their web construction and stabilimentum decoration. The results rejected our hypothesis. Web and stabilimentum constructions decreased in the course of the experiment in both the control group and the experimental group. The individuals did not increase their stabilimentum length and did not extend their web areas, in spite of sensory information given by the nectar collector.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1033-1036
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• 2008

In this paper, the analysis of impact damage behavior of a reinforced concrete structure that undergoes both a shock impulsive loading and an impact loading due to the air blast induced from an explosion is performed. Firstly, a pair of multiple loadings are selected from the scenario that an imaginary explosion accident is assumed. The RC structures strengthened with glass fiber reinforced polymer (GFRP) composites are considered as a scheme for retrofitting RC wall structures subjected to multiple explosive loadings and then the evaluation of the resistant performance against them is presented in comparison with the result of the evaluation of a RC structure without a retrofit. Also, in order to derive the result of the analysis similar to that of real explosion experiments, which require the vast investment and expense for facilities, the constitutive equation and the equation of state (EOS) which can describe the real impact and shock phenomena accurately are included with them. In addition, the numerical simulations of two concrete structures are achieved using AUTODYN-3D, an explicit analysis program, in order to prove the retrofit performance of a GFRP-strengthened RC wall structure.

• Smart Structures and Systems
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• v.15 no.3
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• pp.505-522
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• 2015

Variation of temperature is a primary environmental factor that affects the behavior of structures. Therefore, understanding the mechanisms of normal temperature-induced variations of structural behavior would help in distinguishing them from anomalies. In this study, we used the structural health monitoring data of the Shanghai Yangtze River Bridge, a steel girder cable-stayed bridge, to investigate the mechanisms of thermally induced vertical deflection ($D_T$) at mid-span of such bridges. The $D_T$ results from a multisource combination of thermal expansion effects of the cable temperature ($T_{Cab}$), girder temperature ($T_{Gir}$), girder differential temperature ($T_{Dif}$), and tower temperature ($T_{Tow}$). It could be approximated by multiple linear superpositions under operational conditions. The sensitivities of $D_T$ of the Shanghai Yangtze River Bridge to the above temperatures were in the following order: $T_{Cab}$ > $T_{Gir}$ > $T_{Tow}$ > $T_{Dif}$. However, the direction of the effect of $T_{Cab}$ was observed to be opposite to that of the other three temperatures, and the magnitudes of the effects of $T_{Cab}$ and $T_{Gir}$ were found to be almost one order greater than those of $T_{Dif}$ and $T_{Tow}$. The mechanisms of the thermally induced vertical deflection variation at mid-span of a cable-stayed bridge as well as the analytical methodology adopted in this study could be applicable for other long-span cable-stayed bridges.

• Journal of the Korean institute of surface engineering
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• v.37 no.5
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• pp.296-300
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• 2004

The defects of partial denture frameworks are mainly shrinkage porosity, inclusions, micro-crack, particles from investment, and dendritic structure. In order to investigate a good casting condition of partial denture frameworks, the three casting alloys and casting methods were used and detected casting defects were analyzed by using electrochemical methods. Three casting alloys (63Co-27Cr-5.5Mo, 63Ni-16Cr, 63Co-30Cr-5Mo) were prepared for fabricating partial denture frameworks with various casting methods; centrifugal casting (Kerr, USA), high frequency induction casting (Jelenko Eagle, USA), vacuum pressure casting (Bego, Germany). The casting temperature was $1,380^{\circ}C$ (63Co-27Cr-5.5Mo and 63Ni-16Cr) and $1,420^{\circ}C$ (63Co-30Cr-5Mo). The casting morphologies were analyzed using FE-SEM and EDX. The corrosion test of the dendritic structure was performed through potentiodynamic method in 0.9% NaCl solutions at $36.5^{\circ}C$ and corrosion surface was observed using SEM. The defects of partial denture frameworks improved in the order of centrifugal casting, high frequency induction casting, and vacuum pressure casting method, especially, pore defects were found at part of clasp in the case of centrifugal casting method. The structure of casting showed dendritic structure for three casting alloys. In the 63Co-27Cr-5.5Mo and 63Co-30Cr-5Mo, $\alpha$-Co and $\varepsilon$-Co phases were identified at matrix and $${\gamma}$-Ni_2$Cr second phase were shown in 63Ni-16Cr. Also, the corrosion resistance of cast structure increased in the order of vacuum pressure casting, high frequency induction casting, and centrifugal casting method.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.540-545
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• 2007

The tilting train is able to tilt its body towards the center of the turning radius, preventing roll-over of the train as it runs on a curved rail at high-speed. This train, widely accepted for commercial purpose internationally, is very beneficial in that the operating time is shortened without much capital investment to the infrastructure where there are many curved rails. Over several years, the Korea Railroad Research Institute (KRRI) has developed such a train. In this paper, the safety of the Korean tilting train express (TTX) is investigated using a dynamic simulation model. Since proper safety standards have not been established for the TTX, those for the Korean train express (KTX) is employed to analyze the safety and ride comfort of the TTX. This study is useful in predicting the behavior of the TTX and ride comfort, and conforms that designed TTX is stable enough to satisfy the safety standards. It would be useful to recommend proper normal operating speed and determine the maximum safety speed, according to the result. Furthermore, it would be possible to provide basic reference data when analyzing the dynamic effect of the catenary system and the fatigue of the bogie.

• Journal of Distribution Science
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• v.15 no.10
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• pp.51-63
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• 2017

Purpose - The current study examines the shopping behavior of Chinese tourists who purchase Korean cosmetics when visiting Korea, based on expectancy-disconfirmation of shopping satisfaction and brand attitude toward Korean cosmetics. A moderating effect of consumer conformity on the relationships between cosmetics selection factors and two dimensions of disconfirmation - expectation and performance is also examined. Research design, data, and methodology - We conducted a survey with 250 Chinese tourists who visited Jeju, Korea and had purchased Korean cosmetics during their stay. Excluding 43 respondents' inputs because of incomplete answers and missing values, 207 responses were used in the final analysis. All hypotheses were tested using structural equation model (SEM). Results - We found that the Chinese tourist expectations had positive impact on their satisfaction, and the factors for cosmetic selection had a positive effect on shopping satisfaction and brand attitude. A moderating effect of consumer conformity was found to be significant. Conclusions - Given the significantly increased demand for Korean cosmetics from Chinese tourists, Korean cosmetics firms need to better understand cosmetics selection attributes and preference of Chinese tourists, which can provide a guideline to develop retail stores and distribution outlets for Chinese tourists.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.590-595
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• 2008

In the present paper, the impact damage behavior of steel plate reinforced concrete panels exposed to shock impulsive loading and fragment impact loading is investigated. To evaluate the retrofit performance of a steel-strengthened concrete panels, a numerical experiment using a numerical simulation with AUTODYN, an explicit analysis program is introduced because a real explosion experiment requires the vast investment and expense for facilities as well as the deformation mechanisms are too complicated to be reproduced with a conventional closed-form analyses. The model for the analysis is simplified and idealized as a two-dimensional and axisymmetric case controled with geometry, boundary condition and material properties in order to obtain a resonable computation time. As a result of the analysis, panels subject to either shock loading or fragment loading without the steel plate reinforcement experience the perforation with spalled fragments. In addition, the panels reinforced with steel plate can prevent the perforation and provide the good mechanical effect such as the increase of global stiffness and strength through the composite action between the concrete slab and the steel plate.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.91-96
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• 2006

Recently, the development construction of New Masan Container Terminal (1-1 Phase) with private investment would be set for opening in the 2011 year in Masan Port, Korea However, as new container terminals of the Pusan New Port and 'the New Ulsan Container Terminal neighboring Masan Port will be also planned to open around the time, the strategy establishment for Masan Port is required for a keen competition among these ports. To provide it with strategic points, we applied SP model used for customers' behavior method to analyze customer's preference changes with the shifts of the ports' conditions for customers.

• Fashion & Textile Research Journal
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• v.6 no.2
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• pp.184-194
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• 2004

The purpose of this study was to understand the relationship between life style that a consumer is pursuing and purchasing frequency among the purchasing behaviors in internet shopping mall. As a result, the factors of life style with respect to purchasing attitude of the consumer were categorized into 'price advising type', 'price-quality identifying recognition type', 'brand-oriented type', 'shopping time-effort non-investment type', and 'price-quality comparing type'. It showed that there was a close relationship between the life style and the purchasing frequency in internet shopping mall and that there was a significant influence between the life style and the purchasing frequency. The result of this study indicated that the relationship between the life style and purchasing frequency in internet shopping mall was actualized by measuring the purchasing inclination of the consumer under various situations of psychologically descriptive characteristics and desire and simulation. Therefore, this fact suggests that it is very important to measure the accurate purchasing attitude of its consumer when setting up the marketing strategy of internet shopping mall.

• Korean Management Science Review
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• v.29 no.3
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• pp.135-156
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• 2012

Due to the rapid growth of social networking community (SNC), research into SNC user's behavior has recently emerged as an important issue in information systems. An individual makes a decision whether or not to continually use his or her own SNC and to purchase digital items to decorate it. Most previous research has focused on a user's continuance intention and has ignored the importance of purchase intention. This study develops and empirically tests an integrated model designed to predict a user's two types of behavioral intention：continuance intention and purchase intention based on the expectation-confirmation model (ECM) and a dual model of relationship maintenance mechanism.The results indicate that perceived usefulness, satisfaction, personalization, and switching cost have important influences on the formation of SNC continuance intention. The results also show that perceived usefulness and satisfaction does not have any significant impacts on purchase intention, while personalization, learning, attractiveness of alternatives, and continuance intention significantly affect it.