• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.95-101
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• 2017

In this paper, the sizing removal condition for the pretreatment of composite materials is obtained numerically by applying an image processing algorithm and nickel-plated carbon fiber is fabricated by a dry process method to enhance its electromagnetic shielding performance. Sizings that are wrapped in a polymer type material during the manufacturing of carbon fiber should be removed for dry coating. A numerical value, that is the correlation, can be obtained by determining the regular pattern of the carbon fiber in the image taken by a scanning electron microscope (SEM) after the sizing is removed. The application of the proposed numerical method to the SEM image of the fiber after the sizing is removed with solution, compressed air, solution and compressed air (hybrid), showed that this method of eliminating the sizing is superior to the hybrid method. Then, by spreading the carbon fiber roll with the sizing removed, we were able to produce nickel plated carbon fiber by the roll-to-roll sputtering method. The electromagnetic shielding performance of the fabricated 30, 40 and 100 nickel coated carbon fibers was measured. The Korea Advanced Institute of Science and Technology evaluated the electromagnetic shielding performance of the 100 nickel-coated carbon fiber to have a maximum value of 73.2 (dB) and a minimum value of 66.7 (dB). This is similar to the electromagnetic shielding rate of copper and shows that this material can be used as a cable for EV / HEV automobiles.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.2
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• pp.103-116
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• 2006

By executing corrosion experiment on Inconel 600, 690 used to material of S/G tube in domestic NPP, this paper show estimation of amount of product such as Co-58, Co-60, Cr-51, Mn-54, Fe-59 which are main exposure cause to the workers in NPP. Therefore, Making the 12 samples consisted of Inconel 600, 690, whole corrosion experiment was carried out for 60 days(each pH by 20 days). The conditions of those tests were similar or more harsh than actual conditions of domestic NPP. The Glow Discharge Spectrometer(GDS) was used for quantitative analysis of results. The results of using GDS, the Inconel 600 corrodes more than Inconel 690 at pH 7 and pH 9. However, it is observed that Inconel 690 corrodes more than Inconel 600 at pH 4. Those results is estimated that test sections had the effect of transient. The long terms of experiment is required to minimize and solve the problem.

• Cartoon and Animation Studies
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• s.34
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• pp.167-195
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• 2014

A handwritten poster named "How are you, really?" appeared on December 10, 2013. And other handwritten posters sympathizing with it followed in places and are on everyone's lips hotly through internet and SNS. Such a social phenomenon is delivered to readers as a form of article in different meanings according to the viewpoint of each press. It is also delivered to readers as a material for delivering a meaning of a specific case in four panel comics strips and satirical cartoon of newspaper. This is because that comic strips of the press are now having a power to enlighten readers on the key point of a case easily and intuitively together with catharsis from the position of meditating the world. Notwithstanding differences depending on the viewpoints of the press or cartoonist, four panel comics strips and satirical cartoon on the newspaper are fulfilling their social role having their own voice. Of the genres of comic strips, social role of the comics of the press can be divided largely into two things. First, they actively intervene in social phenomena. In other words, comics of the press make their position and insistence on social phenomena clearly by exaggeration and emphasis. Second, they persuade or enlighten readers by concrete directions, which means that comics of the press make reader with similar viewpoint emphasize by delivering a clear message. This study aims to assert that comic strips are the most important medium with social role and responsibility. As part of studies on the social role of comics, this study wish that comic strips can be able to deviate from vicious circle of being socially condemned for reason of negative portion.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.55-61
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• 1997

In order to effectively utilize the fish and squid skin wastes derived from marine processing manufacture, the skin wastes of some pelagic fishes such as yellowfin sole, red cod, cod, Allaska pollack and flying squid were screened for the raw material of edible gelatin and studied some properties of those gelatins. The content of total collagen in the red cod skin was the highest (28.4 g/100 g wet skin), while that in the flying squid skin was the lowest (11.1 g/100 g wet skin) and those of another fishes were similar. Acid soluble collagens in the skins of the fishes and flying squid were $68.9\~84.8\%\;and\;44.3\%$, respectively. But showed no difference in the amino acid composition between acid soluble and insoluble collagens. Those collagens were consisted $\alpha\;and\;\beta$ chain and $\alpha$ chains extracted from fish skins except red cod and flying squid skins were hetero. The collagen of yellowfin sole skin exhibited slightly higher denaturation temperature $(25.4^{\circ}C)$ and also physical properties such as gel strength, melting point and gelling point were better than those of the other species.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.31-36
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• 2008

This work was performed to evaluate the effect of membrane material and structure on fouling in a submerged membrane bioreactor(MBR). Three types of microfiltration membranes with the same pore size of 0.1 $\mu$m but different materials, polytetrafluoroethylene (PTFE), polycarbonate(PCTE) and polyester(PETE), were used. While PETE membrane exhibited the most rapid flux decline throughout the operation, PCTE and PTFE had a similar tendency with regard to permeability. Difference in permeability between PETE and the other membranes gradually decreased with time, which was probably due to chemical cleaning. The higher TOC rejection of PETE membrane could be attributable to its faster fouling, resulting from a larger amount of foulants to get attached to the membrane in a shorter time. DOC fractionation using a DAX-8 resin showed that the composition of each fraction between the supernatant and permeates did not change significantly with operation time, indicating that membrane hydrophilicity/hydrophobicity was not a dominant factor affecting to MBR fouling in this study. Compared to other membranes, the fouling of PETE membrane was more influenced by pore clogging (irreversible fouling), which would probably contribute to a higher organic rejection of the PETE membrane.

• Elastomers and Composites
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• v.49 no.1
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• pp.1-12
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• 2014

Blocking of fuel filter in aircraft greatly can affect loss of pilot's life and of the aircraft. The investigation of failures is, thus, of vital importance in preventing incidents in advance. The fuel filter of aircraft plays an important role in filtering various debris from jet fuel. It filters impurities smaller than 10 ${\mu}m$ particles from jet fuel provided with the speed of 1,330 pounds per hour. It must be replaced per 500 h on the basis of operating time. However, even before reaching 500 h, the warning sign lighted on due to blocking of fuel filter. Recently, these similar defects have happened repeatedly. Therefore, in this study, the cause of blocking fuel filter in aircraft was investigated using various analytical techniques such as FT-IR microscopy, FE-SEM/EDS, and total sulfur determinator. Consequently, the blocking material of fuel filter was identified to an accelerator from the integral fuel tank sealant. And a mechanism for the formation of the blocking material of fuel filter by an accelerator blooming phenomenon in fuel tank was suggested.

• Journal of the Korean Wood Science and Technology
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• v.39 no.2
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• pp.140-147
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• 2011

The strength properties of wooden retaining wall which was made with pitch pine were evaluated. Wooden retaining wall was made with diameter 90 mm of pitch pine round posts treated with CUAZ-2 (Copper Azole). The length of the front stretcher of the retaining wall was 3,000 mm. The distance between the headers (the notched member) is 1,000 mm in center and is 900 mm in side. There were connections every 2,000 mm because actually the length of stretcher is limited in the retaining wall. The strength test was carried out according to connection type because the section between stretchers can act as a defect. A result of the strength test according to connection type confirms that connection does not act as defect because the strength of retaining wall in single stretcher is similar to that in the section between stretchers. The strength test of the wooden retaining wall was carried out in 5 types according to the condition of the base section. When the upper soil pressure was 9.8 kN/$m^2$, the maximum load of the retaining wall fixing the front foundation shows higher values than those of others. But the total deformation is lower in the retaining wall not to fix a base section than in that to fix a base section. It is thought that the retaining wall not to fix a base section shows low value because the deformation is distributed throughout the retaining wall and it is confirmed that the soil pressure affects supporting the structure because the deformation of the retaining wall under low pressure is 3~4 fold higher than those of others. The failure mode of the retaining wall is the overturning type because the high section is deformed. Mostly, the failure mode is the separation of the header in the notched section.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.460-466
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• 2014

To evaluate wood charcoal as raw material for mineral water production, dissolution of inorganic ions from charcoal to water, pH and adsorption ability of chlorine in water were investigated as main variables. More potassium ion was dissolved in water as higher temperature manufactured charcoal but other ions showed no difference with different charcoal making temperatures. Highest dissolved cation was potassium followed by calcium and sodium. Among wood species, charcoal from Quercus variabilis and Platanus occidentalis showed significantly higher potassium content in water than that of larch, red pine and white pine. Other cations had similar pattern to the potassium but their difference was not apparent as much as potassium. pH value of water treated with charcoal was higher for wood charcoals from Platanus occidentalis (pH 8.5) and Quercus variabilis (pH 8.4) which contained higher inorganic cations. In chlorine removal in water by charcoal, all wood charcoals showed greater chlorine removal than that of the control, but softwood charcoals resulted in higher removal than those of hardwoods. There was no significant difference in the dissolution of cations and pHs between particle charcoal and whole charcoal. With easy of control, whole charcoal is better for mineral water making raw material than particle charcoal does.

• Food Science and Preservation
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• v.12 no.5
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• pp.496-500
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• 2005

To develop functional food material using Rhodiola dumulosa(RD), the biological activities such as antioxidation, antiproliferation in the cancer cells and immuno-activity in macrophage cells were investigated with hexane, ethylacetate, n-butanol, methanol and water fractions of RD 80% methanol extract. Hydrogen-donating activities of hexane, ethyl acetate, n-butanol, methanol and water fraction were 28.30, 53.21, 35.48, 42.64 and 21.14%, respectively, at a concentration of 100 ${\mu}g/mL$, and the activity of ethyl acetate fraction was similar to as that of BHT. After treated for 48 hrs, the ethyl acetate fraction decreased the proliferation of the A549 and SW480 cells in a dose-dependent manner at concentration of 10, 50, and 100 ${\mu}g/mL$, the activities were higher than other fractions. Morphology of cells treated with the ethyl acetate fraction for 48 hr at 100 ${\mu}g/mL$ was distorted with shrank cell mass, and the cell number was lower than that of control cells the macrophage cells treated. The methanol fraction was significantly induced NO production compared with untreated control cells at above 10 ${\mu}g/mL$ concentration. These results indicate that RD would be used the functional food material.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.1
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• pp.31-36
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• 2013

Acetylated Cellulose Ether (ACE), cellulose-based amphiphilic polymer with hydrophilic and hydrophobic, was synthesized and investigated in terms of its solubility and wettability for organic solvents and water. Acetyl group was substituted to the cellulose ether in a hydrophilic polymer by esterification. As a result of FT-IR, the peak corresponding to the hydroxyl group decreased and carboxyl acid peak increased with increasing reaction time and temperature, which signified the increase in the degree of acetylation of the ACE. There were similar thermal decomposition behaviors before and after esterification reaction until $800^{\circ}C$ so that the reaction occurred without significant structural changes of cellulose backbones. The solubility parameter of the ACE had a range of 18.5~26.4, and its viscosity and turbidity were controlled according to the solubility parameter of organic solvents. The ACE showed the hydrophilicity because the contact angle of the ACE was higher than the cellulose ether. These results confirmed that the ACE had the hydrophobicity and hydrophilicity due to the ether which was glucosidic bonding between the glucose units and un-reacted hydroxyl functional groups in the ACE.