• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.737-742
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• 2002

The chief factors for the penetration and diffusion of chloride ions in concrete are water-cement ratio(w/c), aging, thickness of cover concrete, chloride ions concentration of given environment, wet and dry conditions and etc. In this study, effect of w/c and aging on the characteristics of chloride ions diffusion in concrete were researched when environmental factors for the penetration and diffusion of chloride ions were constant. For this purpose, the voltages passing through the diffusion cell were measured by using accelerated test method using potential difference, and then diffusion coefficients of chloride ions by using Andrade's method were estimated for 44%, 49.5% and 55% of w/c, respectively. As a result, correlation among diffusion coefficients of chloride ions, w/c and aging were concluded through multiple regression model.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.211-218
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• 2018

Different packaging methods and storage temperatures were tested to determine the storage stability of beef dry-aged for 21 days based on microbial, physicochemical, and sensory qualities. After completion of the dry aging, the dried surface of beef sirloin was trimmed off, and the beef was packaged using two different methods (oxygen-permeable wrap or vacuum packaging) and stored at different temperatures ($3{\pm}2^{\circ}C$ or $-23{\pm}2^{\circ}C$) for 0, 7, 14, or 21 days. Lipid oxidation and the sensory quality of the dry-aged beef were not affected by the packaging method and storage temperature during storage. No microbial growth was observed over the storage period in the vacuum-packaged dry-aged beef, regardless of the storage temperature. However, dry-aged beef in the oxygen-permeable wrap packaging showed microbial spoilage with 8.82 log CFU / g at day 7 of the refrigerated storage. The vacuum-packaged dry-aged beef showed the lowest values (p < 0.05) in $a^*$ and chroma at days 14 and 21 at $3^{\circ}C$, and days 7 and 14 at $-23^{\circ}C$, respectively. Therefore, it is recommended that dry-aged beef with wrap packaging stored in refrigerated conditions should be consumed as quickly as possible due to microbial growth. For long-term storage, dry-aged beef should be frozen because freezing can extend the color stability up to day 21 of storage without adverse effects on the hygienic or meat quality aspects of dry-aged beef.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.11-16
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• 2011

This study was carried out in order to elucidate the effect of latex dosage and properties on aging behavior of coated paper. The coated paper with five different coating formulations were prepared and also four different latices were used. The coated paper were thermally aged at $105^{\circ}C$ for 14 days and the optical properties were measured. Increasing latex content increased the magnitude of reduction in brightness and whiteness. In addition, the variations in CIE a$^*b^*$ were larger with increasing latex dosage. Latex which has the lower gel content and the higher Tg showed the higher reduction in brightness and whiteness and much variation in CIE a$^*b^*$. However the particle size of latex didn't affect to thermal behavior of coated paper. These results indicate that latex which has higher Tg and lower gel content is the one of the main factors affecting aging behavior of coated paper.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2106-2108
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• 2005

This paper describes a method of lifetime expectation for the dry-type molded transformer which is widely used in the domestic distribution system. And the result of the temperature accelerated aging test for the winding insulation and the analyzed report on the reliability are included in this study.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.334-338
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• 2003

The objective of this study was to demonstrate whether or not the deleterious effects of accelerated aging on seed vigour and viability are alleviated by interaction with gamma irradiation. Seeds of soybean (Glycine max L.) were artificially aged and subsequently irradiated with 4 and 8 Gy of gamma irradiation. Germination rate was negatively affected by accelerated aging and positively by gamma irradiation, with a positive interaction of a 3day-seed aging treatment occurring with 4 Gy, possibly suggesting that 4 Gy of gamma irradiation partially offset the adverse effects of seed aging on germination. However, 5-day aged seeds did not gain any benefits from the gamma irradiation. Electrolyte leakage from the seeds increased with the duration in days aged. Irradiation, however, did not impose any effects on the leakage. Respiration rate of the seed with hypocotyl and primary root was significantly low for the aged seeds, but not for the seeds with both irradiation and aging treatments. Accelerated aging decreased the dry weight of the hypocotyl and primary root of the seeds without any measurable effects of irradiation. $\alpha$-Amylase activity decreased with seed aging and positively responded to gamma irradiation. The data is discussed with regard to the possible roles of gamma irradiation for improving the seed vigour and viability of aged seeds.

• Food Science of Animal Resources
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• v.43 no.3
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• pp.454-470
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• 2023

This study analyzed the microbiological (Lactobacillus spp., Staphylococcus spp., mold, yeast, aerobic bacteria) and physicochemical properties [pH, salinity, water activity, volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances]. The starters were used by mixing Debaryomyces hansenii separated from Korean Doenjang (D) and fermented sausage (S). The starter was inoculated with dry-cured ham and aged for 6 weeks at 20℃ and 25℃, respectively. The aerobic bacteria, Lactobacillus spp., and Staphylococcus spp. of D, S, and DS treatment showed significantly higher values at 25℃ than at 20℃. Among them, S25 treatment showed a high tendency. At week 6, the mold of the S25 treatment was significantly higher than the S20 treatment, and the yeast was higher in 25℃ than 20℃ (p<0.05). The pH of all treatment groups increased with the aging period. Compared with that at 25℃, the pH was significantly higher at 20℃ (p<0.05). The water activity showed a significant decrease as the aging period increased, and the treatment of D25, S20, and DS20 showed a significantly higher value at week 6 (p<0.05). Compared with that at 20℃, the VBN content was higher at 25℃. At week 6, the VBN contents of the C20, S25, and DS25 groups were higher than those of the other treatment groups. Therefore, inoculation of D. hansenii separated from fermented sausage produced in Korean starter at 25℃ is expected to improve the safety of harmful microorganisms and physiochemical properties in dry-cured ham.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.221-224
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• 1997

In this study we investigated the acting characteristics of Polymers for electrical insulation by UV radiation and salt water spray treatment. We used the Polymers such as EPDM, SR. PTFE. EVA. We measured contact angle and surface resistance to know the aging characteristic of Polymer surface. And we use SEM to observe the change of the surface shape. Dry flashover voltage test impulse voltage test were carried for the polymer insulator(EVA) . Through this experiment and the analysis we could know the polymers have a good resistance to weathering conditions like as salt spray UV irradiation and mix of them. And we can compare the aging characteristics between Polymers. As a result, we could know that the surface characteristics of PTFE is better than the other. And the degree, electrical characteristics is affected by change of surface shape is not big.

• Journal of Animal Science and Technology
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• v.62 no.5
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• pp.692-701
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• 2020

This study evaluated the quality characteristics of crust derived from dry-aged Holstein and Hanwoo loins and their effects on food as additives. With respect to physicochemical properties, we examined the proximate composition, pH value, salinity, color, water and fat absorption, emulsifying capacity, and swelling yield. The protein and ash contents in the Holstein crust were significantly higher than those in the Hanwoo crust (p < 0.0001). The fat content in the Hanwoo crust was significantly higher than that in the Holstein crust (p < 0.01). The salinity, lightness, and yellowness of the Hanwoo crust were significantly lower than those of the Holstein crust (p < 0.001). Furthermore, the pH value and emulsifying capacity of the Hanwoo crust were significantly higher than those of the Holstein crust (p < 0.001). The fat absorption of the Holstein crust was significantly higher than that of the Hanwoo crust (p < 0.001). The swelling yield of the Holstein crust was significantly higher than that of the Hanwoo crust at pH 3 and 4 (p < 0.001), whereas the swelling yield of the Hanwoo crust was significantly higher than that of the Holstein crust at pH 7 (p < 0.001). Principal component analysis of dry-aged Hanwoo, Holstein, and non-aged Holstein showed different flavor patterns for each sample. Finally, the results showed that the crusts derived from dry-aged Hanwoo and Holstein loins were suitable flavor enhancers.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.4
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• pp.1-6
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• 2011

The elder population with 65 years old or more in Korea has been entered into an aging society as 9.1[%] in 2005 to 14.3[%] in 2018. The elder population in 2026 will be expected to 20.8[%] with the rapid aging society. In this study, there has been conducted a study on development of headlamp for elder friendly vehicle in order to ffrom two different groups, one group for elder with over 65 ages, the other group for compared ages(20 ages, 30~50 ages). Glare test and forward visibility test were performed on wet and dry road conditions. As the result of these tests, it showed to prefer headlamp installed partially yellow coated bulb, which gives warm feeling on dry road condition. Forward visibility of headlamp which developed to fit on wet road condition is similar to existing HID headlamp. Glare was evaluated less than halogen and HID headlamp. However, it need to more improve glare and forward visibility performance of headlamp for old drivers.

• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.63-73
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• 2007

In this paper, we discussed the hazard of ignition on the bimetal type thermostat molded by phenol resin with case study and accelerated aging test. We experimented three type thermostats molded by phenol resin which are used on hot/cold water dispenser. On the case study, the thermostat was origin of 6re and dry tracking occurred around it's moveable contactor. On the accelerated aging test, the more thermostat was switched, the more damaged it become. One of the A-type thermostats that is similar type on the case study fired around moveable contactor. We therefore confirmed that the tracking around the moveable contactor of bimetal type thermostat molded by phenol resin could be origin of fire and it is available to reduce of fire that using noncombustible material for molding of bimetal type thermostat.