• The Journal of Engineering Geology
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• v.8 no.3
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• pp.285-296
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• 1998

As a part of the study for understanding the deep geological structure of the Ogcheon Zone, both gravity and geomagnetic surveys are performed. A 70km survey line of which direction is nearly perpendicular to major faults in the southern tip of the Zone. The observed data are corrected and transformed into Bouguer and total magnetic intensity anomalies, respectively. Recent studies for petrology and geochemistry in the southwestern Ogcheon Zone in the vicinity of the survey line are reviewed for better interpretation. Both gravity and geomagnetic anomalies abruptly change around Janghung area, the southern boundary of the, Ogcheon Zone. This rapid increase of Bouguer anomaly around Janghung area can be explained by a deep seated normal fault with fairy large displacement between Precambrian gneisses and the denser intermediate plutonic rocks. It is believed that the fault acted an important role for the formation and evolution of the Ogcheon Zone. A pseudomagnetic intensity anomaly is calculated from the Bouguer anomaly assuming that the both anomalies are associated with the common source. From the origin of the survey line to the 50km point, the calculated anomaly coincides with observed magnetic anomaly. Whereas both anomalies show negative correlation in the outside 50km. From the residual Bouguer anomalies, the subterranean geological structure is provided through the iterative forward method. The initial model is obtained from informations about the surface geology as well as the results of the inverse method.

• School Mathematics
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• v.11 no.2
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• pp.317-333
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• 2009

The purpose of this study was to examine the thinking characteristics of mathematically gifted elementary school students in the process of modified prize-sharing problem solving and each student's thinking changes in the middle of discussion. To determine the relevance of the research task, 19 sixth graders enrolled in a local joint gifted class received instruction, and then 49 students took lessons. Out of them, 19 students attended a gifted education institution affiliated to local educational authorities, and 15 were in their fourth to sixth grades at a beginner's class in a science gifted education center affiliated to a university. 15 were in their fifth and sixth grades at an enrichment class in the same center. Two or three students who seemed to be highly attentive and express themselves clearly were selected from each group. Their behavioral and teaming characteristics were checked, and then an intensive observational case study was conducted with the help of an assistant researcher by videotaping their classes and having an interview. As a result of analyzing their thinking in the course of solving the modified prize-sharing problem, there were common denominators and differences among the student groups investigated, and each student was very distinctive in terms of problem-solving process and thinking level as well.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.381-385
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• 2010

Five types of determination methods including the Soxhlet method as well as 3 kinds of extraction solvents, were used for the determination of accurate crude fat contents in wheat flour and 5 kinds of dry noodles. According to the results, crude fat contents were 0.09~1.37% in the wheat flour and 0.07~1.36% in the dry noodle samples. This variation resulted from the types of lipids in the wheat flour and various kinds of dry noodles. Nutrition facts labels showing crude fat contents in the 5 kinds of domestic dry noodle samples indicated levels of 0~1.5%. Lipid composition and content were determined in order to investigate these differences. The results indicated free lipid at 1.02% and bound lipids at 0.21% in the wheat flour, and free lipids at 0.95~1.01% and bound lipid at 0.21~0.25% in the wheat flour. Polar and nonpolar lipid contents were also measured in all samples. Neutral lipid, glycolipid and phospholipid contents in the free lipid were 58.5%, 33.6%, and 8.6% in the wheat flour, and 49.2~58.2%, 33.3~41.6%, and 8.5~9.3% in the dry noodle samples, respectively. For bound lipids, amounts were 16.7%, 33.5%, and 49.5% in the wheat flour, and 13.2~15.3%, 35.6~45.7%, and 41.6~49.4% in the dry noodle samples, respectively. Based on these results, an acid hydrolysis methods should be used to determine accurate crude fat contents in wheat flour and dry noodles.

• Journal of Science and Technology Studies
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• v.20 no.1
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• pp.39-85
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• 2020

With the development of information technology, fake news is becoming a serious social problem. Individual measures to manage the problem, such as fact-checking by the media, legal regulation, or technical solutions, have not been successful. The flood of fake news has undermined not only trust in the media but also the general credibility of social institutions, and is even threatening the foundations of democracy. This is why one cannot leave fake news unchecked, though it is certainly a difficult task to accomplish. The problem of fake news is not about simply judging its veracity, as no news is completely fake or unquestionably real and there is much uncertainty. Therefore, managing fake news does not mean removing them completely. Nor can the problem be left to individuals' capacity for rational judgment. Recurring fake news can easily disrupt individual decision making, which raises the need for socio-technical measures and multidisciplinary collaboration. In this study, we introduce a new public online platform for fake news management, which incorporates a multidimensional and multidisciplinary approach based on citizen science. Our proposed platform will fundamentally redesign the existing process for collecting and analyzing fake news and engaging with user reactions. People in various fields would be able to participate in and contribute to this platform by mobilizing their own expertise and capability.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1075-1080
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• 2008

Fine-sized $Gd_2O_3:Eu$ phosphor powders were prepared by post-treatment of the precursor powders with hollow shape obtained by spray pyrolysis from the spray solution with citric acid and flux material. Citric acid enabled the synthesis of fine-sized phosphor powders after post-treatment by increasing the hollowness of the precursor powders. The phosphor powders prepared from the spray solution without citric acid had several microns size. Flux materials increased the mean sizes of the phosphor powders. However, flux materials improved the photoluminescence intensities of the phosphor powders under ultraviolet. $Li_2CO_3$ as the flux material was appropriate to prepare the fine-sized $Gd_2O_3:Eu$ phosphor powders with high photoluminescence intensity. The phosphor powders below 3 wt% $Li_2CO_3$ of phosphor had submicron sizes after post-treatment temperatures of $1,050^{\circ}C$ and $1,150^{\circ}C$. The photoluminescence intensity of the phosphor powders post-treated at $1,150^{\circ}C$ was 124% of that of the phosphor powders post-treated at $1,050^{\circ}C$.

• Korean journal of communication and information
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• v.56
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• pp.175-193
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• 2011

This study explored how South Korean newspapers covered North Korea's second nuclear test in May of 2009. Findings show that South Korean newspapers mostly reported North Korea's nuclear experiment in relatively negative tones. Their coverage mainly focused on the influences of nuclear threat from the North on the military, political and economic areas in South Korea. However, the media's agenda settings and frames were not similar in terms of each paper's political and ideological inclination. Whereas the progressive papers, such as the Hankyoreh and the Kyunghyang Shinmun, recognized that the current nuclear issue in Korean peninsula is getting worse because of South Korea's rigorous pressure on North Korea, the conservative papers, such as the Chosun Ilbo and the Donga Ilbo, see that the deadlock between North and South mainly comes from the system malfunction of North Korea. To prevent the current impasse, the left-side papers emphasized to develop the six-party talk in dealing with North Korean issue, while the right-wing papers paid attentions to the West's sanctions on North Korea and ensuring national security.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.2
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• pp.89-103
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• 2020

A frizz hair is referred to the fly-away hairs that have become bulky or deviated from the regular hair and the cause of that is not clear known. The internal lipids are related to the physical properties of hair such as elasticity and tensile strength and interracial studies have previously conducted to relate the lipid mass and Afrikaan hair, which has a lot of frizzy hair. Although washing hair is the only way to control the hair loss without damage of hair surface, the number of washing and lipid loss are not linearly correlated. In this study, the amount of lipid hair was analyzed by washing the hair with a few different types of shampoos containing various conditioning polymers and oils of different polarities. The results confirmed that the higher the polarity of the oil, the higher the lipid content. This method was applied to Indian frizzy hair to evaluate the degree of frizziness and found that the frizzy volume was more severe for a hair with less lipids. On the other hand, the frizzy hair volume of fly-away hairs was observed more broadly for the hairs with higher lipid contents. In addition, the friction on the surface of the hair did not differ due to the oil treatment. Taken together, it was concluded that hair frizzing was affected by the amount of lipids in the hair rather than by the adhesion between the oils. Thus, this study suggests that controlling the lipid contents in hair may be an important solution in the development of hair anti-frizzy technology.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.19 no.4 s.74
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• pp.389-398
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• 2006

Structural optimization design has been developed with finite element analysis using effective and fast computational technology. Especially topology optimization design has been recently often used since it yields an optimal topology as well as an optimal shape under satisfied constraints. In general in finite element analysis, it is assumed that the structural material properties such as Young's modulus and Poisson's ratio and the variable of applied loading are fixed with obvious values in structure. However practically these values may take uncertainties because of environmental effect or manufactural error of structures. Therefore static or dynamic analysis of the structures may make an error, then finally it may have an influence on qualify of optimal design. In this study, the topology optimization design of structure is carried out using so called the interval finite element method, and the analysis method Is proposed. The results are also validated by comparing with conventional topology optimization results of density distribution method and finite element analysis results. The present method can be used to predict the optimal topology of linear elastostatic structures with respect to structural uncertainty of behavior.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.2
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• pp.87-95
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• 2018

This paper introduces a new explicit spectral element method for the simulation of SH-waves in semi-infinite domains. To simulate the wave motion in unbounded domains, it is necessary to reduce the infinite extent to a finite computational domain of interest. To prevent the wave reflection from the trunctated boundaries, perfectly matched layer(PML) wave-absorbing boundary is introduced. The forward problem for simulating SH-waves in PML-truncated domains can be formulated as second-order PDEs. The second-order semi-discrete form of the governing PDEs is constructed by using a mixed spectral elements with Legendre-gauss-Lobatto quadrature method, which results in a diagonalized mass matrix. Then the second-order semi-discrete form is transformed to a first-order, whose solutions are calculated by the fourth-order Runge-Kutta method. Numerical examples showed that solutions of SH-wave in the two-dimensional analysis domain resulted in stable and accurate, and reflections from truncated boundaries could be reduced by using PML boundaries. Elastic wave propagation analysis using explicit time integration method may be apt for solving larger domain problems such as three-dimensional elastic wave problem more efficiently.

• Journal of Life Science
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• v.23 no.4
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• pp.569-577
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• 2013

Soy sauce is a traditional fermented seasoning in several oriental countries, such as Korea and Japan, and recently it has been reported to have biological activities. In Korean soy sauce, soybeans and wheat are the two main raw materials. Polysaccharides that originate from the cell wall of soybeans are resistant to enzymatic hydrolysis. These polysaccharides remain in the soy sauce even after fermentation and are termed Kanjang polysaccharides (KPS). In this study, polysaccharides were obtained from dialysate of different soy sauces labeled as A~T and manufactured by fermentation or the acid-hydrolyzate method. We investigated anti-inflammatory activities by examining the effects of these KPS on proinflammatory cytokine release and mRNA expression in mast cells. Histamine and ${\beta}$-hexosaminidase release were strongly decreased by the KPS treatment in RBL-2H3 cells. Treatment with KPS clearly reduced mRNA expression and the release of the proinflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor-alpha (TNF-${\alpha}$) in PMACI-stimulated HMC-1 cells. In particular, KPS derived from fermented Kanjang products showed a significant anti-inflammation effect on mast cells compared to the acid-hydrolyzed Kanjang products. This study suggests that KPS appear to be effective in suppressing allergic inflammatory reactions.