• Journal of Life Science
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• v.17 no.3 s.83
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• pp.362-367
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• 2007

A total of 5 female elk deer (220 $kg{\pm}10$ kg) were included in a study on the changes in physico-chemical properties of deer meat during storage at $4^{\circ}C$. The deers were exposed to normal pre-slaughter handling and put under anesthesia before slaughtered. The loin and leg cuts were deboned from the carcass after 24hrs slaughter. The samples weighing approximately 300 g were packaged using three packaging methods : Atmospheric packaging(A), Vacuum packaging (V) and Modified atmospheric at packaging (M: 80% $CO_2$ +20% $N_2$)and stored for 3, 7, 11, 15, 20 and 25days at $4^{\circ}$. The ability of moisture maintenance tended to be decreased with the passage of storage time, and that of the meats treated with the vacuum wrapping was lower than that with other wrapping methods. TBARS values of the meats with the regardless of treatments was increased with the passage of storage time, although the values with vacuum wrapping was lowest. VBN values of the meats with the regardless of treatments was also increased with the passage of storage time, although the values with vacuum wrapping was also lowest. The pH values of the meats with the regardless of treatments was also increased with the passage of storage time, although the values with vacuum wrapping was also lowest. For the meat softness, the value of the meats treated with atmospheric packaging was increased with the passage of storage time, but the values with vacuum wrapping and modified atmospheric packaging were respectively decreased. There were no significant differences in luminosity of leg, although loin treated with vacuum wrapping was significantly brighter than that with atmospheric packaging and modified atmospheric packaging. In general, the index of red color of the meats treated with vacuum wrapping was higher than that with atmospheric packaging and modified atmospheric packaging. The index of yellow color tended to be decreased after increment for a time with the passage of storage time, although the value with vacuum wrapping was generally higher than that with other wrapping methods.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.285-291
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• 1996

The effect of various packaging methods on Kimchi quality was investigated in order to develop the packaging techniques for preventing commercial Kimchi Products from ination and explosion due to fermentative gas evolved during storage and distribution. Kimchi was packaged in different methods; atmospheric (AP), check-valved (CV), double (DP) and vacuum (VP) packaging. The quality of Kimchi during storage at $10^{\circ}C$ was evaluated ill terms of gas composition, free volume, pH, titratable acidity, color index, lactic acid bacteria and sensory properties. $O_2$ concentration decreased to about 1% at $6{\sim}8$ days of optimal ripening time in all packages except DP, in which it remained around 20%. $CO_2$ concentration reached $70{\sim}90%$ after $6{\sim}8$ days in AP, CV and DP, while it stayed around 10% in DP. The free volume in AP had typical sigmoidal curve similar to $CO_2$ concentration changes. It remained almost constant in CV and DP, but started to increase at the late stage of storage In VP. There was no significant influence of packaging methods on the other quality attributes such as pH, titratable acidity, color index (L.b/a), lactic acid bacteria count and sensory evaluation score. As results, it could be proposed to employ CV and DP method as the effective packaging techniques for preventing commercial Kimchi products from inflation.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.16-21
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• 2007

Twenty pork loins were processed for manufacturing raw hams according to a short-ripening procedure including dry-and wet-curing for 1 week each, followed by ripening for 2 weeks. Raw ham cuts were vacuum-packaged and stored in darkness at 10 and $25^{\circ}C$ for 90 days, and their physicochemical and sensory quality characteristics were investigated. The sodium chloride content of raw hams stored at 10 and $25^{\circ}C$ was maintained at approximately 5.1% throughout storage at either temperature. No significant changes in water, crude protein, crude fat and ash contents were observed in all samples regardless of storage temperature and storage length. Thiobarbituric acid and volatile basic nitrogen values increased continuously during the storage period. The changes in physicochemical characteristics including pH, water activity texture lipid oxidation and protein degradation, and sensory attributes appeared to be more pronounced at $25^{\circ}C$ than at $10^{\circ}C$ over the storage period. At prolonged storage periods, a significant quality loss in the aspect of texture changes including hardness, brittleness, elasticity, cohesiveness, gumminess, and adhesiveness was observed (p<0.05). Based on sensory evaluation scores, It appeared that vacuum-packaged raw ham cuts stored at 10 and $25^{\circ}C$ were not acceptable after 75 and 45 days, respectively.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.3_4
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• pp.97-102
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• 2007

A Korean seasoned meat product, seasoned bulgogi was developed in processing and packaging for improved convenience and extended shelf life. The optimal process conditions were found to consist of aging for $20{\sim}30$ hours at $5^{\circ}C$ and air heating for 20 minutes at $210^{\circ}C$ Aging of 24 hours could attain soft texture with little change in pH, color and total aerobic bacterial count. Appropriate drip level could be achieved at air heating of 20 minutes at $210^{\circ}C$, while the air heating at $180^{\circ}C$ could not give suitable level of texture. Modified atmosphere packaging of 60% $CO_2$ and 40% $N_2$ could preserve the product significantly better compared to control of air package and vacuumed package.

• Applied Science and Convergence Technology
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• v.25 no.2
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• pp.32-35
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• 2016

Using conventional deposition techniques, we demonstrate a method to fabricate ultra-smooth 10 nm silver films without using a wetting layer or co-depositing another material. The argon working pressure plays a crucial role in achieving an excellent surface flatness for silver films deposited by DC magnetron sputtering on an InP substrate. The formation of ultra-smooth silver thin films is very sensitive to the argon pressure. At the optimum deposition condition, a uniform silver film with an rms surface roughness of 0.81 nm has been achieved.

• Applied Science and Convergence Technology
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• v.26 no.2
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• pp.30-33
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• 2017

ZnO thin films which were deposited by RF magnetron sputtering system were annealed by furnace and insitu heat treatment methods. We investigated the effect of heat treatment method on physical properties of ZnO thin films. The structural and optical properties of ZnO thin films were improved by heat treatment. Through the annealing treatment of ZnO film by furnace, the good crystallinity and ultraviolet emission were obtained. These results are attributed to the improved formation of Zn-O bond in ZnO thin film annealed at by furnace. We confirm that the formation of Zn-O bond plays an important role in obtaining the excellent structural and optical properties of ZnO thin films.

• Korean Journal of Metals and Materials
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• v.50 no.2
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• pp.93-99
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• 2012

The mechanical properties of nano composites were evaluated for structural performance in order to enhance their applicability to the car and machine industrial fields. Carbon fiber reinforced plastics (CFRP) and GFRP were manufactured by vacuum-assisted resin transfer molding (VARTM) process with good mechanical properties. Tensile test was conducted to obtain the process factor of each composite. Also, carbon nano fiber (CNF) was dispersed in the composites and the relationship between the mechanical property and the CNF fraction was compared. The tensile strength and stiffness of 0/90 laminated CFRP were the best. CFRP/CNF (0.5 wt.%) was confirmed to be an excellent material for its elasticity and tensile strength.

• Journal of the Korean Magnetics Society
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• v.17 no.4
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• pp.172-177
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• 2007

In order to detect of the magnetic property in the cell unit, we studied the GMR-SV (giant magnetoresistance-spin valves) biosensor, which was depended on the micro patterned features according to two easy directions of longitudinal and transversal axes. Here, the multi layer structure was glass/NiO/NiFe/CoFe/Cu/CoFe/NiFe. The uniaxial anisotropy direction was applied to the patterned biosensor during the deposition and vacuum post-annealing at $200^{\circ}C$ under the magnitude of 300 Oe, respectively. Considering the magnetic shape anisotropy effect, the size of micro patterned biosensor was a $2{\times}5{\mu}m^2$ after the photo lithography process. By our experimental results, we confirmed that the best condition of GMR-SV biosensor should be the same direction of the axis sensing current and the easy axis of pinned NiO/NiFe/CoFe triple layer oriented to the width direction of device, and the direction of the easy axis of free CoFe/NiFe bilayer was according to the longitudinal direction of device.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.402.1-402.1
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• 2016

The performance of solid oxide fuel cells (SOFCs) is directly related to the electrocatalytic activity of composite electrodes in which triple phase boundaries (TPBs) of metallic catalyst, oxygen ion conducting support, and gas should be three-dimensionally maximized. The distribution morphology of catalytic nanoparticle dispersed on external surfaces is of key importance for maximized TPBs. Herein in situ grown nickel nanoparticle onto the surface of fluorite oxide is demonstrated employing gadolium-nickel co-doped ceria ($Gd0.2-xNixCe0.8O2-{\delta}$, GNDC) by reductive annealing. GNDC powders were synthesized via a Pechini-type sol-gel process while maximum doping ratio of Ni into the cerium oxide was defined by X-ray diffraction. Subsequently, NiO-GNDC composite were screen printed on the both sides of yttrium-stabilized zirconia (YSZ) pellet to fabricate the symmetrical half cells. Electrochemical impedance spectroscopy (EIS) showed that the polarization resistance was decreased when it was compared to conventional Ni-GDC anode and this effect became greater at lower temperature. Ex situ microstructural analysis using scanning electron microscopy after the reductive annealing exhibited the exsolution of Ni nanoparticles on the fluorite phases. The influence of Ni contents in GNDC on polarization characteristics of anodes were examined by EIS under H2/H2O atmosphere. Finally, the addition of optimized GNDC into the anode functional layer (AFL) dramatically enhanced cell performance of anode-supported coin cells.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.111.2-111.2
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• 2015

Typical electrodes (metal or indium tin oxide (ITO)), which were used in conventional organic light emitting devices (OLEDs) structure, have transparency and conductivity, but, it is not suitable as the electrode of the flexible OLEDs (f-OLEDs) due to its brittle property. Although Graphene is the most well-known alternative material for conventional electrode because of present electrode properties as well as flexibility, its carrier injection barrier is comparatively high to use as electrode. In this work, we performed plasma treatment on the graphene surface and alkali metal doping in the organic materials to study for its possibility as anode and cathode, respectively. By using Ultraviolet Photoemission Spectroscopy (UPS), we investigated the interfaces of modified graphene. The plasma treatment is generated by various gas types such as O2 and Ar, to increase the work function of the graphene film. Also, for co-deposition of organic film to do alkali metal doping, we used three different organic materials which are BMPYPB (1,3-Bis(3,5-di-pyrid-3-yl-phenyl)benzene), TMPYPB (1,3,5-Tri[(3-pyridyl)-phen-3-yl]benzene), and 3TPYMB (Tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane)). They are well known for ETL materials in OLEDs. From these results, we found that graphene work function can be tuned to overcome the weakness of graphene induced carrier injection barrier, when the interface was treated with plasma (alkali metal) through the value of hole (electron) injection barrier is reduced about 1 eV.