• Tribology and Lubricants
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• v.24 no.4
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• pp.170-178
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• 2008

In this paper, it is described how the problems appeared at the previous proto type sensor are improved. As changing the pressure and temperature of engine oil in a test rig, the modified sensor is tested. Then, the measured results of capacitance and the corresponding dielectric constants under various temperatures and pressures are shown. It turns out that the electrical signal gotten from the electrodes of newly developed sensor can be more stable under the various operating conditions.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.22-26
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• 1997

A small scale centrifugal oil separator consisted of two concentric tubes was fabricated for spilt oil recovery. With speed control of the inner tube, its performance of oil separation was investigated. Oil-water mixture is separated by forced vortex motion with the rotating inner tube. Velocity and pressure distributions in the tubes were calculated. Control of rotating speed, which is the most influencing parameter, showed an optimum value 946rpm corresponding to the acceleration of 20g at the inner tube surface. Separation performance was suddenly deteriorated at rotating speed higher than 1200rpm.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.15-15
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• 2021

Seed coat color and seed weight are among the key agronomical traits that determine the nutritional quality of soybean seeds. This study aimed to evaluate the contents of total protein, total oil and five prominent fatty acids in seeds of 49 soybean varieties recently cultivated in Korea, and assess the influences of seed coat color and seed weight on each. Total protein and total oil contents were in the ranges of 36.28-44.19% and 13.45-19.20%, respectively. Likewise, individual fatty acid contents were in the ranges of 9.90-12.55, 2.45-4.00, 14.97-38.74, 43.22-60.26, and 5.37-12.33% for palmitic, stearic, oleic, linoleic, and linolenic acids, respectively. Our results found significant variations of protein, oil and fatty acid contents between the soybean varieties. Moreover, both seed coat color and seed weight significantly affected total oil and fatty acid contents. Total protein content, however, was not significantly affected by any factor. Among colored soybeans, pale-yellow soybeans were characterized by a high level of oleic acid (30.70%) and low levels of stearic (2.72%), linoleic (49.30%) and linolenic (6.44%) acids, each being significantly different from the rest of colored soybeans (p < 0.05). On the other hand, small soybeans were characterized by high levels of all individual fatty acids except oleic acid. The level of oleic acid was significantly high in large seeds. Cluster analysis grouped the soybeans into two classes with notable content differences. Principal component analysis also revealed fatty acids as the prime factors for the variability observed among the soybean varieties. As expected, total oil and total protein contents showed a negative association with each other (r = -0.714, p < 0.0001). Besides, oleic acid and linoleic acid showed a tradeoff relationship (r = -0.936, p < 0.0001) which was reflected with respect to both seed coat color and seed weight. In general, the results of this study shade light on the significance of seed coat color and seed weight to distinguish soybeans in terms of protein, oil and fatty acid contents. Moreover, the soybean varieties with distinct characteristics and nutritional contents identified in this study could be important genetic resources for consumption and cultivar development.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1170-1177
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• 2005

Terminal-restriction fragment length polymorphism (T-RFLP) analysis was used to monitor inoculated oil-degrading microorganisms during bioremedial treatability tests. A pair of universal primers, fluorescently labeled 521F and 1392R, was employed to amplify small subunit rDNA in order to simultaneously detect two bacterial strains, Corynebacterium sp. IC10 and Sphingomonas sp. KH3-2, and a yeast strain, Yarrowia lipolytica 180. Digestion of the 5'-end fluorescence/labeled PCR products with HhaI produced specific terminal-restriction fragments (T-RFs) of 185 and 442 bases, corresponding to Corynebacterium sp. IC10 and Y. lipolytica 180, respectively. The enzyme NruI produced a specific T-RF of 338 bases for Sphingomonas sp. KH3-2. The detection limit for oildegrading microorganisms that were inoculated into natural environments was determined to be $0.01\%$ of the total microbial count, regardless of the background environment. When three oil-degrading microorganisms were released into oil-contaminated sand microenvironments, strains IC10 and 180 survived for 35 days after inoculation, whereas strain KH3-2 was detected at 8 days, but not at 35 days. This result implies that T-RFLP could be a useful tool for monitoring the survival and relative abundance of specific microbial strains inoculated into contaminated environments.

• Korea Trade Review
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• v.44 no.6
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• pp.105-118
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• 2019

In the past two decades, due to the rapid fluctuations in the oil supply and demand in Northeast Asia as well as a surge in oil prices in the early 2000s, Korea has been developing the Northeast Asia Oil Hub project as a national project. This project was promoted based on the policy consideration that the nation's energy security and regional development can be promoted by establishing an oil hub in Northeast Asia that can eventually replace Singapore as East Asia's oil logistics hub. Following the construction of a large-scale oil storage facility in Yeosu in 2013, the main project in Ulsan has suffered many difficulties due to environmental changes such as the supply and demand of oil and political factors. The survey, which investigated the performance, problems, and prospects of the oil hub project, illustrates that scores of all sectors are of average level. In terms of performance and prospects, policies such as facility investment, law, and system improvement were determined to be rather high while operational areas such as value-added activities, profitability, and marketing activities were perceived as having more serious problems by respondents. In conclusion, despite the strong potential of Korea's oil hub based on its geographical location, facilities, and oil product capacity, there are problems related to policies, institutions, and investment. In the future, the oil hub business should be reviewed by considering environmental factors, and a drastic improvement plan for attracting foreign investors and oil traders should be established.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.1
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• pp.104-109
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• 2010

Hydro-thermal liquefaction technology for rapeseed straws was investigated the biomass conversion rate with different catalysts and reaction temperatures. NaOH and KOH were used for catalysts, and the reaction temperature were ranged from 180 to $320^{\circ}C$ at every $20^{\circ}C$ of intervals for 10 minutes. The reaction was carried out in a 5,000 mL liquefaction system with dispenser and external electrical furnace. Raw materials (160g), 2,000 mL of distilled water and 10% (wt/wt) of catalyst to plant residue were fed into the reactor. It was observed that the maximum crude oil yield was about 36% at temperature range, $260{\sim}280^{\circ}C$ with KOH and at $300^{\circ}C$ with NaOH, respectively. It was observed that the more calorific values of crude oil, the higher reaction temperature with KOH, but it had the reverse pattern in NaOH.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1421-1430
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• 2010

Polycyclic aromatic hydrocarbons (PAHs) were investigated in seawater and marine sediment from Anmyundo coastal area after oil spill. The concentrations of total PAHs in surface and bottom of seawater at August were 31.1 to 142.6 ng/L and 5.9 to 50.9 ng/L in August and November, respectively. The concentrations of PAHs in sediment were 21.0 to 102.9 ng/g D.W. and 32.3 to 57.4 ng/g D.W. in August and November, respectively. PAHs concentrations in seawater and sediment in August were higher than those in November about 2.5 and 1.4 times, respectively. Diagnostic ratio (PhA/AnT and FluA/Pyr) were investigated to identify source of PAHs in seawater and sediment. The PAHs in seawater originated from pyrolytic source and those in sediment originated from pyrolytic and petrogenic source. The glass, wood and coal origin was higher than petroleum origin on the combustion origin of PAHs in seawater and sediment. The seawater of Anmyundo costal area recovered from oil spill, but the sediments of that were weakly influenced by oil spill until now. Because this area is developed many fishing grounds, demanded Long Term Environmental Monitoring Program (LTEMP). The concentrations of PAHs on depth of sediments were investigated at station 8 and 10. The concentrations of PAHs were decreased with increasing depth.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1721-1725
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• 2014

The objective of this study was to evaluate the in vitro effects of coconut materials on ruminal methanogenesis and fermentation characteristics, in particular their effectiveness for mitigating ruminal methanogenesis. Fistulated Holstein cows were used as the donor of rumen fluid. Coconut materials were added to an in vitro fermentation incubated with rumen fluid-buffer mixture and timothy substrate for 24 h incubation. Total gas production, gas profiles, total volatile fatty acids (tVFAs) and the ruminal methanogens diversity were measured. Although gas profiles in added coconut oil and coconut powder were not significantly different, in vitro ruminal methane production was decreased with the level of reduction between 15% and 19% as compared to control, respectively. Coconut oil and coconut powder also inhibited gas production. The tVFAs concentration was increased by coconut materials, but was not affected significantly as compared to control. Acetate concentration was significantly lower (p<0.05), while propionate was significantly higher (p<0.05) by addition of the coconut materials than that of the control. The acetate:propionate ratio was significantly lowered with addition of coconut oil and coconut powder (p<0.05). The methanogens and ciliate-associated methanogens in all added coconut materials were shown to decrease as compared with control. This study showed that ciliate-associated methanogens diversity was reduced by more than 50% in both coconut oil and coconut powder treatments. In conclusion, these results indicate that coconut powder is a potential agent for decreasing in vitro ruminal methane production and as effective as coconut oil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.24-28
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• 2009

This study was conducted to evaluate the growth characters and yield components of 18 collected sesame cultivars to get basic information on the variation for the sesame breeding using principal component analysis. All characters except days to flowering, days to maturity and 1,000 seed weight showed significantly different. Seed weight per 10 are showed higher coefficient of variance. Capsule bearing stem length and liter weight showed positive correlation with seed yield per 10 are. The principal components analysis grouped the estimated sesame cultivars into four main components which accounted for 83.7% of the total variation at the eigenvalue and its contribution to total variation obtained from principal component analysis. The first principal component ($Z_1$) was applicable to increase plant height, capsule bearing stem length and 1,000-seed weight. The second principal component ($Z_2$) negatively correlated with days to flowering and maturity by which it was applicable to shorten flowering and maturity date of sesame. At the scatter diagram, Yangbaek, Ansan, M1, M2, M4, M7 and M9 were classified as same group, but M10, Yanghuk, Kanghuk, M5, M6, M12 and M13 were classified as different group. This results would be helpful for sesame breeder to understand genetic relationship of some agronomic characters and select promising cross lines for the development of new sesame variety.

• Korean Journal of Pharmacognosy
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• v.8 no.2
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• pp.69-72
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• 1977

The investigation is involved with the development of the new method of decoction preparation in order to prevent the loss of volatile oil from crude drugs. Volatile oil in crude drug containig volatile oil ranged from 1 to 2.2% in content. Volatile oil content in crude drung prescription which main component is a crude drug containing volatile oil was $0.11{\sim}0.39\;ml$. It was found that traditional method of decoction preparation has caused to lose almost all of the volatile oil. Application of method of Pharmacopoea (Kp II) for the preparation of decoction prevented the loss of volatile oil from one half to two-third of its content. The method of Pharmacopoea to which air condenser was attached could completely prevented the loss of volatile oil from the preparation.