• Membrane Journal
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• v.17 no.3
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• pp.174-183
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• 2007

The manufacturing process of metal membrane made of only metal mesh and both metal mesh and powder with using rolling process have been studied. In the rolling of metal mesh, selected metal meshes were rolled with the reduction ratio of 10%, 20%, and 30%, respectively. Such rolling process resulted in the decrease of mesh pore size through reduction the cross sectional area of mesh and changing the diameter of mesh wires. Also, it enhanced the filtration ratio of rolled mesh which is almost same as the filtration ratio of upper grade unrolled mesh and the reliability of membrane by making pore size distribution become more uniform. In fabricating metal powder layer onto metal mesh, using PVA(polyvinyl alcohol) as a binder of powder, drying the metal powder layer at $100^{\circ}C$ for 1 hr, and sintering it at $1,000^{\circ}C$ for 3 hr in vacuum were to be optimum conditions for obtaining good quality of metal powder layer on metal mesh with high pore density but no crack. With additional rolling of metal powder layer on metal mesh with 30% reduction before sintering, metal membrane which filtration ratio is about $0.7{\mu}m$ has been successfully manufactured.

• Korean Journal of Poultry Science
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• v.41 no.3
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• pp.181-189
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• 2014

This study was conducted to investigate the effect of chicken skin and pork backfat on quality of Dakgalbi-taste chicken sausage as fat sources. The sausages were manufactured with 100% chicken breast without fat sources, 85% chicken breast meat with 15% chicken skin or 85% chicken breast meat with 15% pork backfat, respectively. Batters for production of chicken sausage were mixed with 5% Dakgalbi sauce and 4.92% ingredients (meat and lipid basis) for 20 min and then stuffed into casing. All cooked sausages were vacuum-packaged and stored at $4^{\circ}C$ for 14 days. Moisture and crude protein contents were higher in the control, and crude lipid content was higher in chicken sausage with pork backfat (p<0.05). Unsaturated fatty acids content and monounsaturated fatty acids/saturated fatty acids ratio of sausage with pork backfat were lower than those of control and sausage with chicken skin (p<0.05), which were influenced by fatty acids compositions of fat sources. The chicken sausage with pork backfat showed a lower hardness and chewiness, and higher springiness measured by food texture analyzer. The sausage with pork backfat had a high level of water holding capacity (WHC) during storage (p<0.05). In conclusion, Dakgalbi-taste chicken sausage containing chicken skin had higher unsaturated fatty acid compositions, but showed lower textural quality compared with that containing pork backfat.

• Journal of the Korean Society of Radiology
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• v.3 no.4
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• pp.29-33
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• 2009

Recently, the compound materials(a-Se, $HgI_2$, PbO, CdTe, $PbI_2$, etc.) that are used in flat panel x-ray imager have been studied for digital x-ray imaging. In this paper, the signal detection properties of $HgI_2$ and a-Se conversion layer, are compared. The thick $HgI_2$ film is fabricated by special particle-in-binder method and the conventional vacuum thermal evaporation is used for a deposition of a-Se film. And an electrical characteristic measurements were investigated about leakage current, signal response property and x-ray sensitivity. From the experimental results show that the $HgI_2$ film has a low operation voltage and high signal generation than that of a-Se.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.89-98
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• 2007

This study was carried out to compare the quality characteristics including aroma compounds and pattern of M. Biceps femoris from Korean native black pigs (70kg, 6 months, KNP) and modern genotype pigs (103kg, 6 months, Landrace×Yorkshire, MGP) during vacuum-storage at 2±0.2℃ for 12 days. KNP had high contents of crude protein and ash, but low content of moisture as compared to MGP (p<0.05). KNP showed lower pH and higher cooking loss than MGP (p<0.05) during storage. CIE a* and b* values of KNP significantly higher during storage as compared to those of MGP (p<0.05). TBARS value of KNP significantly increased after 8 days as compared to that of MGP (p<0.05). Shear force value of KNP was higher than that of MGP until 8 days (p<0.05). Volatiles by SPME-GS/MS was slightly different between KNP and MGP, but aroma pattern by electronic nose was not different. Therefore, KNP had redder and darker color, higher cooking loss and harder texture than MGP. The sensory quality of KNP was better than those of MGP (p<0.05), although aroma characteristics by instruments were not different between KNP and MGP.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.406-418
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• 2020

When developing weapons systems, it is important to implement the functions and performance of equipment suitable for development purposes, but it is very important to ensure that the equipment is capable of operating without any vacuum with reliability after development. Therefore, various activities are carried out to enhance reliability of equipment. Reliability is enhanced by using high-specification parts in development, reliability verification through analysis, and testing using development prototypes to reinforce and improve the parts that are lacking in equipment. However, recently, development schedules are shortened due to rapidly changing external conditions and technologies, and there are cases where sufficient reliability growth activities were not carried out due to problems such as cost. Examples are projects that perform reliability activities only in analytical methods (reliability, FMECA). In this paper, analyzing and testing methods for analysis and testing were carried out on the same equipment through FMECA and super-accelerated life test, the contents of reliability growth activity were derived, the results of design change/review were accordingly compared, the differences between the two methods were analyzed, and measures were proposed to strengthen reliable growth activities. It was concluded that reliable growth activities through analysis from the beginning of development and reliable growth activities through testing should be carried out at the completion of initial prototype production.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.216-221
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• 2017

Reducing optical reflection in the visible light range, in order to increase the share of transmitted light and avoid the formation of ghost images in imaging, is important for polymer lens applications. In this study, polymer lenses with refractive indices of n=1.56, 1.60, and 1.67 were fabricated by the injection-molding method with a polymer lens monomer, dibutyltin dichloride as the catalyst and an alkyl phosphoric ester as the release agent. To investigate their anti-reflection (AR) effects, various AR coating structures, viz. a multi-layer AR coating structure, tri-layer AR coating structure with a discrete approximation Gaussian gradient-index profile, and tri-layer AR coating structure with a quarter-wavelength approximation, were designed and coated on the polymer lens by an E-beam evaporation system. The optical properties of the polymer lenses were characterized by UV-visible spectrometry. The material properties of the thin films, refractive index and surface roughness, were analyzed by ellipsometry and AFM, respectively. The most effective AR coating structure of the polymer lens with low refractive index, n=1.56, was the both side coating of multi-layer AR coating structure. However, both side coating of the tri-layered discrete approximation Gaussian gradient-index profile AR coating structure gave comparable results to the both side coating of the multi-layer AR coating structure for the polymer lens with a high refractive index of n=1.67.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.421-431
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• 2016

The purpose of this study was to identify the influence of depression, social isolation, and meaning in life on the swallowing related quality of life in patients with dysphagia. In this study, 87 the dysphagia patients diagnosed with stroke, degenerative disease, and neurological disorder in a general or rehabilitation hospital in Seoul, Gyeonggi, and Incheon were assessed. The data were collected between February and April, 2015 using CES-D, RULS, PIL, SWAL-QOL. The data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation, and stepwise multiple regression with SPSS 22.0. Of the participants, 20.7% reported having had depression, 92.0% middle-high social isolation and 64.4% existential vacuum. The mean scores were SWAL- QOL 158.89(35.97). Stepwise multiple regression revealed that tube feeding to have the greatest effect on SWAL-QOL(${\beta}=-0.57$, p<.001), followed in order by age (${\beta}=0.26$, p=.001), lower MIL (${\beta}=0.19$ p=.014), and education (${\beta}=0.17$, p=.032). The most influential factor to SWAL-QOL was tube feeding. These variables accounted for 50.7% of SWAL-QOL in dysphagia patients (F=28.84 p=.031). Therefore, it is essential to develop the intervention that can improve the meaning in life in patients with dysphagia. In addition there is a need to study the psychological factors and quality of life of tube feeding.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.1
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• pp.65-73
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• 2016

Korea Food and Drug Administration (KFDA) has officially announced 2,4-dinitrophenylhydrazine (DNPH) derivatization - high performance liquid chromatography (HPLC) methods for analysis of formaldehyde. This study was conducted to develop a convenient derivatization method for cosmetics by improving complex pre-treatment procedures included in KFDA method. To simplify pre-treatment procedures of KFDA method, reaction conditions including pH, time and temperature were optimized. This pre-treatment method does not require complicate pre-treatment steps of KFDA method such as pH adjustment of test solution with acetate buffer (pH 5.0), solvent-solvent partitioning with dichloromethane and concentrating procedure with vacuum evaporator. Formaldehyde-dinitrophenylhydrazone (formaldehyde-DNP) product produced by derivatization reaction was separated and quantified with a reversed-phase HPLC, which was slightly modified with KFDA method. The linearity test showed good results with 0.9999 of correlation coefficient ($r^2$) in the range of 2 ~ 40 ppm of standard solutions. In this method, limit of detection (LOD) and limit of quantitation (LOQ) values for formaldehyde were 0.2 ppm and 0.5 ppm, respectively. In addition, recovery test demonstrated that the method was also accurate and reproducible. Therefore, the proposed method can be applicable to rapid analysis of formaldehyde in cosmetics.

• Korean Journal of Materials Research
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• v.22 no.1
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• pp.54-60
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• 2012

The particle size of MgO was examined as a function of the Na content in $Mg(OH)_2$ powders and the calcination temperature. $Mg(OH)_2$ suspension was obtained by dropwise precipitation of $Mg(NO_3)_2{\cdot}6H_2O$ and NaOH solutions. The suspension was diluted by varying the dilution volume ratio of distilled water to $Mg(OH)_2$ suspension to change the Na salt concentration in the suspension. $Mg(OH)_2$ slurry was filtered and dried at $60^{\circ}C$ under vacuum, and then its $Mg(OH)_2$ powder was calcined to produce MgO with different amount of Na content at $500\sim900^{\circ}C$ under air. Investigation of the physical and chemical properties of the various MgO powders with dilution ratio and calcination temperature variation was done by X-ray diffraction, transmission electron microscopy, BET specific surface area and thermal gravimetric analysis. It was observed that MgO particle size could depend on the condition of calcination temperature and dilution ratio of the $Mg(OH)_2$ suspension. The particle size of the MgO depends on the Na content remaining in the $Mg(OH)_2$ powder, which powder was prepared by changing the dilution ratio of the $Mg(OH)_2$ suspension. This change increased as the calcination temperature increased and decreased as the dilution ratio increased. The growth of MgO particle size according to the increase of temperature was more effective when there was a relatively high content of Na. The increase of Na content lowered the temperature at which decomposition of $Mg(OH)_2$ to MgO took place, thereby promoting the crystal growth of MgO.

• Journal of the Korean Magnetics Society
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• v.23 no.6
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• pp.193-199
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• 2013

The regional distribution of magnetic isotropy depending on the post annealing condition for the dual-type structure GMR-SV (giant magnetoresistance-spin valve) of NiFe/Cu/NiFe/IrMn/NiFe/Cu/NiFe multilayer was investigated. The rotation of in-plane ferromagnetic layer induced by controlment of the post annealing temperature inside of the vacuum chamber. The magnetoresistive curves of a dual-type IrMn based GMR-SV depending on the direction of the magnetization easy axis of the free layer and the pinned layer are measured by between $0^{\circ}$ and $360^{\circ}$ angles for the applied fields. The optimum annealing temperature having a steady and isotropy magnetic sensitivity of 1.52 %/Oe was $107^{\circ}C$ in the rotational section of $0{\sim}90^{\circ}$. By investigating the switching process of magnetization for an arbitrary measuring direction, the in-plane orthogonal magnetization for the dual-type GMR-SV multilayer can be used by a high sensitive biosensor for detection of magnetized micro-beads.