• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.449-470
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• 2018

A review of research trends on wood surface protection for exterior use obtained the following conclusions: It has been reported that inorganic compounds such as chrome and copper used as wood preservatives can protect wood from weathering. It has been shown that precoating with hydrophobic substances such as wax and oil, UV absorbers, and HALS (Hindered Amine Light Stabilizers) enhances weathering resistance on the surface of ACQ-treated wood. Opaque coatings of paint/stains and semitransparent stains on the surface of preservative treated wood can increase the synergistic effects on prevention of weathering deterioration. Also the need for repainting periodically for the protection of the preservative treated wood surface has also been suggested. ZnO or $TiO_2$ of fine particles, metal ions such as Co, Cr, Fe, Mn, Ni and Ti, and UV absorbers such as tris-resorcinol triazine derivatives, triazine and benzotriazole were introduced as additives for preventing UV in the transparent coating on wood. Several reports showed that chemical modification such as methylation, acetylation, or alkylations have made some increases the effects of preventing weathering with the increasing weight gain of chemical formulas. In heat-treated wood, there were various contradictory reports on the resistance of weathering, and there were some other reports emphasizing the necessity of painting with UV resistance, which leads to the necessity of more advanced studies.

• Animal Bioscience
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• v.34 no.4
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• pp.662-669
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• 2021

Objective: Effects of linseed oil (LO) supplementation on the fat content and fatty acid profile of breast meat, and the expression of three genes in the liver, breast muscle and fat tissues of commercial 154-day-old hybrid male turkeys were investigated. Methods: The animals in the control group were fed a commercially available feed and received no LO supplementation (n = 70), whereas animals in the LO group (n = 70) were fed the same basic diet supplemented with LO (day 15 to 21, 0.5%; day 22 to 112, 1%). The effect of dietary LO supplementation on fatty acid composition of breast muscle was examined by gas chromatography, and the expression of fatty acid desaturase 2 (FADS2), peroxisome proliferator activated receptor gamma (PPARγ), and insulin-like growth factor 1 (IGF1) genes was analysed by means of quantitative reverse transcription polymerase chain reaction. Results: The LO supplementation affected the fatty acid composition of breast muscle. Hepatic FADS2 levels were considerably lower (p<0.001), while adipose tissue expression was higher (p<0.05) in the control compared to the LO group. The PPARγ expression was lower (p<0.05), whereas IGF1 was higher (p<0.05) in the fat of control animals. There were no significant (p>0.05) differences in FADS2, PPARγ, and IGF1 gene expressions of breast muscle; however, omega-6/omega-3 ratio of breast muscle substantially decreased (p<0.001) in the LO group compared to control. Conclusion: Fatty acid composition of breast meat was positively influenced by LO supplementation without deterioration of fattening parameters. Remarkably, increased FADS2 expression in the liver of LO supplemented animals was associated with a significantly decreased omega-6/omega-3 ratio, providing a potentially healthier meat product for human consumption. Increased PPARγ expression in fat tissue of the LO group was not associated with fat content of muscle, whereas a decreased IGF1 expression in fat tissue was associated with a trend of decreasing fat content in muscle of the experimental LO group.

• International Journal of Highway Engineering
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• v.12 no.1
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• pp.55-59
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• 2010

High VOC(Vehicle Operating Cost) is the main reason for the rehabilitation of paved road and VOC is composed of fuel consumption, lubricant oil consumption, parts consumption, etc. Fuel consumption is one of the largest components of VOC and the roughness of road represents the deterioration level of the road. For these reasons, the fuel consumption is measured for different IRI(International Roughness Index) in this study. The fuel consumption was measured by processing the voltage signal of fuel injector of vehicle and the speed was measured with GPS. The change rate of fuel consumption for different IRI can be calculated with the results of this test. It's concluded that fuel consumption(L/100km) of medium and large passenger car increases 7 times fast of the increase of IRI(m/km) around 3.5m/km in the speed range of 40 ~ 100km/h, and fuel consumption is the best at 60km/h.

• Transactions on Electrical and Electronic Materials
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• v.14 no.6
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• pp.308-311
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• 2013

The effect of an electric field on the ac electrical treeing in various epoxy/reactive diluent systems was studied in a needle-plate electrode geometry. Diglycidyl ether of bisphenol A (DGEBA) type epoxy was used as a base resin, and 1,4-butanediol diglycidyl ether (BDGE) or polyglycol (PG) as a reactive diluent was introduced to the DGEBA system, in order to decrease the viscosity of the DGEBA epoxy system. BDGE was acted as a chain extender, and PG acted as a flexibilizer, after the curing reaction. To measure the treeing initiation time and the propagation rate, three constant alternating currents (ac) of 10, 13 and 15 kV/4.2 mm (60 Hz) were applied to the specimen, in a needle-plate electrode arrangement, at $30^{\circ}C$ of insulating oil bath. When 10 kV/4.2 mm (60 Hz) was applied, the treeing initiation time and the propagation rate in the DGEBA system were 356 min and $1.10{\times}10^{-3}$ mm/min, respectively, those in the DGEBA/BDGE system were 150 min and $1.14{\times}10^{-3}$ mm/min, respectively. Those in the DGEBA/PG system were 469 min and $1.05{\times}10^{-3}$ mm/min, respectively. As 15 kV/4.2 mm (60 Hz) was applied, the propagation rate in the DGEBA system was $5.41{\times}10^{-3}$ mm/min, and that in the DGEBA/PG system was $1.42{\times}10^{-3}$ mm/min. These values meant that PG could be used as a reactive diluent in the DGEBA system, without the deterioration of the insulation breakdown property.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.477-481
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• 2001

A large quantity of fat is added in processing of emulsion sausage. It is bring about deterioration and toxic substance by oxidation. Antioxidants are generally used as a protection material of oxidation for a storage and preservation of foods. In terms of stability of foods and health of human, development of a high effective antioxidants in a natural is required. Chitosan which is made from chitin by processing of deacetylase, has various function of antibiosis, antimutation and antioxidation and so on. We studied about the antioxidation of chitosan using to emulsion sausage. As a results, antioxidative effects of chitosan were increased with th large milecular weight and the higher concentration. M.W. 30,000 and M.W. 120,000 of chitosan have more 20% of antioxidation effect in emulsion sausage. Because chitosan have not 100% of antioxidation effect, we concluded that it has synergy effect by using with other natural material which has an effect of antioxidation.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.2
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• pp.1-12
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• 2008

Recently, the roll of bus transit is critical more than before because of the dramatical increase in congestions and oil prices, but bus companies seriously encounter into vicious circle situation such as decrease in passenger demand, income reduction, and revenue deterioration. To tackle this, major metropolitan cities, Seoul, Busan, DaeGu, etc. have introduced a semi-public system to reinforce public function of bus. However, it was resulted in side effects that the main board of bus company did not control theirselves voluntarily, and the management and control of public sectors on bus become very important elements. In this research, the types, limitations, and development of operation-management items, and a methodology for analysis, and changes in those trends are addressed under semi-public system using APTS data. Conclusively, this study could be one of the useful application results and alternatives for the operation-management policy of bus transit-related agencies.

• Ocean and Polar Research
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• v.30 no.1
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• pp.89-107
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• 2008

Marine environment is subject serious destruction because of frequent accidents during exploration of marine resources and overseas transport. Also, as many industrial enterprises discharge high volume of wastes and contamination, marine pollution has become a serious threat to people (especially in China). China is quickly becoming a world economic leader of the 21st century. Rapid industrialization and social changes have raised the standard of living of millions of the Chinese, mainly in the areas of East and South East coast. The process of industrialization, however, is often followed by deterioration of the marine environment and rarely turned around until a country has increased its standard of living. Solving these array of problems will take decades and currently the government is addressing minor specific issues only. Fortunately, the Chinese government has enacted a number of marine pollution control laws. On 25 December 1999, the 13th Session of the Ninth Standing Commettee of the National People's Congress passed the amended the Marine Environment Protection Law of the People's Republic of China. This Law establishes rights and responsibilities of the relevant departments concerning marine environment management and provides for two new chapters on "Marine Environment Supervision" and "Marine Ecological Protection", along with "Supervision of Pollution Prevention for Marine Construction Projects", "Marine Ecological Protection" and "Marine Environment Pollution Prevention for Marine Construction Projects". Also, the Law was amended with provisions for integrated pollution discharge control system and oil spillage emergency response plan and enhanced legal responsibilities. Chinese government recognizes that international and national experience can be useful for China to prevent further ecological degradation of the marine environment.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.250-254
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• 1994

The quality characteristics of freeze-dried Chungkook-jang soup, stored at $25^{\circ}C$, $35^{\circ}C$ and $45^{\circ}C$ was investigated. Peroxide value(POV) was increased as the storage time was extended. Browning reaction occured earlier in the sample stored at $45^{\circ}C$ than those stored at $35^{\circ}C$ and $25^{\circ}C$. Red color developed more intensely in the sample stored at $45^{\circ}C$. However, moisture content was not changed during storage. Regression analyses between sensory scores and quality characteristics showed that the peroxide formation of oil contained in Chungkook-jang soup was the major quality index for the deterioration of Chungkoak-jang soup.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.6
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• pp.104-108
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• 2009

The insulation aging characteristics and structural analysis test were performed to analyze the correlations among the insulation deterioration, diagnostic results and the breakdown strength for the underground power cables. From the results of the degree of crosslinking test, hot-oil test etc., it could be confirmed that there were no manufacturing defects in the power cables under test. From the results of the water tree test and chemical structural analysis, it could be confirmed that the aging status of cable under test were very poor, especially for B-Phase and the degree of aging was increased in the orders of A, C and B-phase. From the above results, it could be concluded that the insulation aging characteristic analysis results were well consistent with the diagnostic and breakdown test results, and also confirmed that the diagnostic system under consideration was successful to discriminate the bad cables which is likely to cause cable system failure.

• Tribology and Lubricants
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• v.37 no.1
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• pp.7-13
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• 2021

Ball bearing is a device that supports and transmits a load acting on a rotating shaft, and it is a type of rolling bearings that uses the rolling friction of the balls by inserting balls between the inner ring and the outer ring. Grease, which is prepared by mixing a thickener with a base oil, is a lubricant commonly used in bearings and has the advantage of a simple structure and easy handling. Bearings are increasingly being used in high value-added products such as semiconductors, aviation, and robots in the era of the 4th industrial revolution. Accordingly, there is an increasing demand for bearing grease. The selection of grease is an important factor in the bearing design. Therefore, a study must be conducted on the grease life evaluation to select an appropriate grease according to operating conditions such as a high temperature, high rotational speed, and high load. In this study, we evaluate the life of ball-bearing grease according to various operating conditions, namely, temperature, speed, and load changes. For this, we develop and theoretically verify a grease life test machine for ball bearings. We conduct a life test of grease according to various operating conditions of bearings and predict the grease life with a 10% and 50% failure probability using the Weibull analysis. In addition, we analyze the oxide characteristics of the grease over time using the Fourier transform infrared spectroscopy and the deterioration characteristics of the grease using the carbonyl index.