• Journal of the Korean Mathematical Society
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• v.46 no.5
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• pp.1105-1117
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• 2009

In this paper a parameter identification problem for a damped sine-Gordon equation is studied from the theoretical and numerical perspectives. A spectral method is developed for the solution of the state and the adjoint equations. The Powell's minimization method is used for the numerical parameter identification. The necessary conditions for the optimization problem are shown to yield the bang-bang control law. Numerical results are discussed and the applicability of the necessary conditions is examined.

• Journal of the Chungcheong Mathematical Society
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• v.24 no.2
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• pp.359-370
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• 2011

In this work, we obtain new solitary wave solutions for some nonlinear partial differential equations. The Jacobi elliptic function rational expansion method is used to establish new solitary wave solutions for the combined KdV-mKdV and Klein-Gordon equations. The results reveal that Jacobi elliptic function rational expansion method is very effective and powerful tool for solving nonlinear evolution equations arising in mathematical physics.

• Korean Architects
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• s.543
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• pp.90-97
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• 2014

• World Technopolis Review
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• v.2 no.1
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• pp.2-9
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• 2013

• JOURNAL OF ELECTRICAL WORLD
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• no.10 s.24
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• pp.33-37
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• 1971

• Journal of the Korea Institute of Information Security & Cryptology
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• v.27 no.4
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• pp.855-861
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• 2017

Gordon & Loeb[1] suggested that the optimal level of investment decision of an enterprise is the point that the marginal benefit(MB) of information security investment is equal to the marginal cost(MC). However, many companies suffering from information security incidents are not aware of the fact that they are experiencing information security accidents and can not measure how much they are affected. In this paper, I propose a model of information security investment decision making under the incomplete information situation by modifying the Gordon & Loeb[1] model and compare the differences in investment level. Under the incomplete information situation the expected return from the information security investment tends to be lower than that of actual information security investment, and the level of investment is also less. This shows that if a third party such as the government gives accurate information such as the rate of incidents of information security accidents and the amount of damages, companies can expand their investment in information security.

• Advances in Traditional Medicine
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• v.7 no.4
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• pp.336-340
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• 2007

Plants from the genus Centaurea (C.) (Family: Asteraceae alt. Compositae), widely distributed in Asia, Europe and North America, have traditionally been used in the treatment of various ailments. As a part of our on-going studies on the plants from the genus C. for their phytochemistry and biological activities, extracts of the seeds of Turkish endemic C. species, C. bornmuelleri and C. huber-morathii, were tested for their cytotoxicity towards the CaCo2 colon cancer cell line as well as for the toxicity towards the brine shrimps, using the MTT and the brine shrimp lethality assays, respectively. Among the extracts, the MeOH extract of these plants showed significant toxicity towards the brine shrimps ($LD_{50}=55.2{\times}10^{-2}\;and\;42.4{\times}10^{-2}mg/ml$, respectively). The MeOH extract of both C. species also inhibited the growth of CaCo2 colon cancer cells in the MTT assay ($IC_{50}$=29.9 and 33.0 g/ml, respectively). As the most prominent activities in both assays were observed with the MeOH extracts, it can be assumed that the compound(s) responsible for these activities are polar in nature.

• Advances in Traditional Medicine
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• v.5 no.3
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• pp.246-250
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• 2005

A number of species of the genus Centaurea (Family: Asteraceae), distributed in various parts of Asia, Europe and North America, have been used in traditional plant-based medicine and reported to possess various medicinal properties. As part of our continuing evaluation of plants from the genus Centaurea for their phytochemistry and biological activities, the dichloromethane (DCM) and methanol (MeOH) extracts of the seeds of Turkish Centaurea species, C. bornmuelleri, C. huber-morathii and C. schiskinii, were screened for antioxidant and antibacterial activities. Among the three species, C. huber-morathii displayed the most prominent antibacterial activity. Both the MeOH and DCM extracts of this plant showed activity against Citrobacter freundii, Enterococcus faecalis and Salmonella goldcoast with the MIC values within the range of $1\;{\times}\;10^{-2}\;to\;1\;{\times}\;10^{-3}\;mg/ml$. The MeOH extract of C schiskinii showed activity $(MIC\;=\;1\;{\times}\;10^{-1}\;mg/ml)$ against Citrobacter freundii and Staphylococcus aureus. While the DCM extract of C. bornmuelleri was only active against Staphylococcus aureus $(MIC\;=1\;{\times}\;10^{-2}\;mg/ml)$, the MeOH extract did not show any inhibitory activity at test concentrations. The DCM and MeOH extracts of all three species demonstrated good degree of antioxidant property in the DPPH assay with the $RC_{50}$ values ranging from $72\;{\times}\;10^{-2}\;to\;31{\times}\;10^{-3}\;mg/ml$. Among these extracts, the MeOH extract of C. hubermorathii was the most active antioxidant extract $(MlC\;=\;31\;{\times}\;10^{-3}\;mg/ml)$.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.6
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• pp.23-30
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• 2018

Gordon Cullen, who tried to understand urban landscapes in terms of visual attention, introduced a concept called 'Space and Infinity' in his book 'Townscape'. According to him, urban images like infinity spreading across the sky are more effectively created when we happen to see an open space while walking along a ground-level street than when we look at the sky. This study aims to quantitatively examine if urban observers pay more attention to spaces like pilotis on the bottom of a building. Thus, this study collected observers on actual urban landscape images and partially-edited images and conducted an experiment by adopting Eye-movement Tracking to find out if they actually pay more visual attention to a space like pilotis. This study selected a total of 50 people as research subjects and divided them into two groups. Image 1 was shown to one group, and Image 2 with the pilotis space edited was shown to the other group. As an experiment to find objective evidences on Gordon Cullen's 'Space and Infinity', this study analyzed difference between Image 1 and Image 2, and it was found that the domain of pilotis showed a value five times higher than the average visual attention since it attracted much visual attention although it was very small in area. That is, it has objectively clarified that people get most fascinated with a place with infinite images in the background like a pilotis space out of all the urban landscapes as Gordon Cullen's theory. In addition, the differences in visual concentration of pilotis space by sex, by subject was examined, and there was no significant difference in visual concentration of pilotis space by gender. As a result of examining the difference of visual concentration by classifying the subjects into architectural related major, the major group showed higher frequency of viewing than the non - major group.

• Fashion & Textile Research Journal
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• v.23 no.6
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• pp.744-757
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• 2021

This study aims to develop a bodice and a jacket in 3D of the late 19th to early 20th based on the pattern drafting book of Gordon S. S., which contains body measurement method and pattern drafting system. The findings of this research are as follows. First, female tops of the late 19th to early 20th century are categorized as outer, jacket, vest, and bodice. Of these, this study highlights the jacket, which can be divided into 4 types: 4 kinds of basic jacket, 2 kinds of riding jacket, bolero jacket, and newmarket jacket. Second, by referring to Gordon's pattern drafting system and book, a bodice was developed in 3D format based on the adherence to the following steps: analysis of the pattern drafting system, pattern drafting, 3D virtual simulation, 3D virtual fitting analysis, and the pattern correction. A bodice pattern corrected by 3D virtual clothing simulation results was proposed. Last, a basic sleeve and collar pattern for a basic jacket was drafted, which was followed by the correction and transformation of the bodice pattern. The jacket developed shows great fit except for the issues at the armhole line and shoulder, which were caused by the unique shape of the sleeves(big sleeve head) of the time. The study attempted to develop the past costumes in 3D, providing the basis for interdisciplinary research in the field of fashion history field and suggesting a new approach for the virtual restoration of costumes. Future studies should target to 3D virtual simulation in accordance to the 3D avatar pose in the developed virtual costume.