• Proceedings of the Petrological Society of Korea Conference
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• 2006.05a
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• pp.61-62
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• 2006

• Journal of Korean Association for Spatial Structures
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• v.11 no.1
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• pp.87-95
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• 2011

This study presents the comparisons between the analysis results based on membrane theory and finite element analysis for the inverted umbrella-type hyperbolic paraboloid shell structure. The effects of the roof angle on the roof deflections, member forces of edge beams and ribs, and shell stress are also investigated with various roof angles. Results show that the membrane theory overestimates the member forces of edge beams and ribs. On the contrary, the shell stresses are underestimated in the membrane theory when compared to the results from the finite element analysis. The deflections of roof slabs by finite element analysis show drastic increasement as the roof angle decreases.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.253-261
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• 2003

Mechanical behavior of composition pound improved by sand compaction pile (SCP) with low replacement area ratio could be more significantly affected by mechanical interaction between sand piles and clays than that of clay ground improved by SD or SCP with high replacement area ratio. It is essential to elucidate the mechanical interaction in the improved clay ground, in order to accurately estimate behavior in reducing settlement of the improved ground and increasing strength of clays. In this paper, through a series of model tests of composition ground improved by SCP with low replacement area ratio, each mechanical behaviors of sand piles and clays in the composition ground during consolidation was elucidated, together with stress sharing behavior between sand piles and clays.

• Polymer(Korea)
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• v.26 no.4
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• pp.492-500
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• 2002

Oxidized-polyacrylonitrile (oxy-PAN) was prepared by oxidation of PAN fiber at $240^{\circ}C$, followed by base catalyzed hydrolysis reaction. The chemical structure of PAN fiber in various pH conditions was characterized by $^{13}C-NMR$ spectroscopy. The characteristic contraction and expansion behavior of oxy -PAN fiber was observed in acidic and basic medium, respectively. In basic condition, water molecules might be absorbed into the fiber with the movement of charge balancing $Na^+$ ion, on the other hand, the water molecules seemed to be expelled in acidic condition to result in contraction. It was also observed that the facile chemical modification occurred due to free diffusion of aqueous reagent into the hydrophilic PAN fiber, and the morphology was affected by pH condition.

• Elastomers and Composites
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• v.36 no.3
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• pp.153-161
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• 2001

The rubber pads era tank which undergo dynamic deformations with the sufficient amplitudes and frequencies lead to a considerable internal temperature rise due to the heat generation. The heat generation which is dependent on the viscoelastic characteristics or a rubber is due to the conversion of partial mechanical energy into thermal energy identical to the area oi hysteresis loop. Heat generation without adequate heat dissipation leads to heat build-up and the excessive temperature rite exerts a bad influence upon the performance and the life of rubber products. In this paper, temperature distributions of the rubber pads of a tank track subjected to dynamic loads are obtained under the assumption of the steady state. Heat generation rates used in this finite element analysis are acquired through experiments and the computed temperature fields are displayed in isothermal contour regions.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.3
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• pp.259-265
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• 2006

Learning and emotions are very important parts to implement intelligent robots. In this paper, we implement intelligent virtual character based on reinforcement learning which interacts with user and have internal emotion model. Virtual character acts autonomously in 3D virtual environment by internal state. And user can learn virtual character specific behaviors by repeated directions. Mouse gesture is used to perceive such directions based on artificial neural network. Emotion-Mood-Personality model is proposed to express emotions. And we examine the change of emotion and learning behaviors when virtual character interact with user.

• Geophysics and Geophysical Exploration
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• v.16 no.3
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• pp.145-153
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• 2013

High-resolution chirp profiles were analyzed to investigate the echo types of near-surface sediments in the Yellow Sea off the Baegryeong Island. On the basis of seafloor morphology and subbottom echo characters, 7 echo types were identified. Flat seafloor with no internal reflectors or moderately to well-developed subbottom reflectors (echo type 1-1 and 1-2) is mainly distributed in the southern part of the study area. Flat seafloor with superposed wavy bedforms (echo type 1-3) is also distributed in the middle part. Mounded seafloor with either smooth surface or superposed bedforms (echo type 2-1, 2-2, and 2-3) occurs in the middle part of the study area. Irregular and eroded seafloor with no subbottom reflectors (echo type 3-1) is present in the northern part of the study area off the Baegryeong Island. According to the distribution pattern and sedimentary facies of echo types, depositional environments can be divided into three distinctive areas: (1) active erosional zone due to strong tidal currents in the northern part; (2) formation of tidal sand ridges in response to tidal currents associated with sea-level rise distributed in the middle part; and (3) transgressive sand sheets in the southern part. Such a depositional pattern, including 7 echo types, in this area reflects depositional process related to the sea-level rise and strong tidal currents during the Holocene transgression.

• Journal of Digital Convergence
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• v.18 no.8
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• pp.111-118
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• 2020

This study conducted an empirical analysis of SSE-listed companies to verify the effects of evaluation and disclosure of internal control systems on the agency costs management and controlling shareholders. Agency costs can affect the valuation of accounting information as asymmetry of information in the relationship between a company and its stakeholders, or induce financial costs as an adverse selection. If the firm's agency costs are reasonable, the valuation of the company can also move in a relatively positive direction. In this study, the evaluation information of the internal control system was analyzed through sales management ratio and equity ratio as substitute variables to analyze the relationship between management and agent costs of the controlling shareholders. In addition, independent control ratio, capital balance ratio, and company scale were used as control variables, as a result of the analysis, the evaluation information of internal control was found to be related to the agency costs of managers and governance structure. This study can be conducted to positive factors in evaluating the reliability and corporate value of accounting information according to the evaluation of internal control of SSE-listed companies and helps to understand the financial reporting environment.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.31-46
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• 2019

As the importance of venture firms has increased as a new growth engine, the South Korea government makes various efforts to establish healthy ecosystems for ventures and start-ups. Especially in order to foster the competitiveness of venture firms, various support policies such as financial and R&D expenses are being expanded and promoted. In this study, the author analyzed the impact of government funding on venture firms' internal competencies and management performance by using the resource-based theory. Moreover, this study tested the moderation effect of firm's growth stages. Unlike previous studies, this study focused on qualitative rather than quantitative aspects of internal competencies and the financial and non-financial performance are used to measure the management performance of the ventures to examine the effects of government funding for venture firms in more details. For the purpose of verifying the hypothesis of this research, "The Research On The Precision Status Of Venture Firms" in 2017 from the Ministry of Small and Medium Business was utilized, which has been compiled since 1999. According to the results of this study, the government funding experience did not significantly affect the company's internal competencies and financial performance, but had a significant impact on the non-financial performance, which in turn seemed to have a significant effect on the financial performance. In addition, it was found that the technology, price, design, and quality competencies affected non-financial performance, while the organizational management and marketing competencies did not. However, the price, design, organizational management, and marketing competencies affected financial performance, while the technology competency was not. Finally, there were no differences in the effectiveness of government funding, depending on the growth stages.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.267-274
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• 2011

The effect of internal ring stiffeners is numerically evaluated for reinforcement of tubular K-joints. Finite element analyses are performed to compute stress of un-stiffened and ring-stiffened K-joints subjected to axial loading. The influence of loading condition and geometrical parameters of ring stiffener on joint behavior is assessed to determine the installation effect of single and double ring stiffeners. The arrangement effect of ring stiffener are evaluated using quantitative analysis compared single ring with double ring stiffeners. Based on the numerical results, practical size of ring stiffener is proposed for design of tubular K-joints.