• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1702-1714
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• 1998

Removal of spilled oil over the sea and the river has become one of the urgent problems in these days. Removing oil using mechanical devices was recommended because chemical dispersion could cause the secondary contamination in the environment. In the present study a series of experiments were carried out to study the effect of operating conditions, especially, the angle between the belt and the fluid surface on the rate of recovery for the spilled oil using a belt skimmer. Three different types of operation, namely, upward pickup, downward pickup and up-and-downward pickup situations have been investigated for various contact angles, belt speeds and oil thicknesses to find the effects on the recovery rate. The highest rate of oil recovery was found in the case of a contact angle of $45^{\circ}$ and downward pickup. Furthermore, an optimal belt speed was found to reach the saturated recovery rate for a given oil thickness.

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.39-54
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• 1994

I am going to survey major topics relating to the title by analyzing the following statistical data. 1 : Global trend of production and import of oil and relating materials 2 : Global trend of major oil production 3 : Capacity of Japanese factory for oil production 4 : Situation of mechanical expression based on raw materials 5 : Change of production amounts of Oil products 6 : Oil production of each items 7 : Imported amounts of oil products 8 : Vegetable oil meals, production, import and global trend 9 : Production of mayonnaise, dressing and edible processing oils 10 : Intake of nutrients, supply of lipids, and consumption of oils 11 : Global production of oleochemicals 12 : Sales amount of oleochemicals 13 : Capacities of fatty acid and fatty alcohol factories 14 : Oleochemical production in 1995 15 : Oleochemical procuction in asia 16 : Production of surfactants for industrial use 17 : Sales amount of detergents and washing materials 18 : Production of soap and synthetic detergent in Japan 19 : Consumption of soap. detergent, and synthetic detergent 20: Relation beween synthetic detergent production and popularization 21 : Biodegradability of soft detergent

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.100-104
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• 2006

The in vitro antimicrobial and antioxidant activities of the essential oil and methanol extracts of Ledum palustre L. were investigated. Using GC-MS analysis, we identified 37 compounds in the essential oil, constituting 87.58% of the total oil. There are several monoterpenes, of which sabinene is the major compound ($16{\sim}17%$). There are several oxygenated monoterpenes of which terpinen-4-ol(7.6%) and myrtenal (3.5%) are the main constituents. $\beta$-Selinene, a-selinene, $\gamma$-elemene, a-caryophyllene are the main sesquiterpenes ($2{\sim}6%$ range). The oil strongly reduced the diphenylpicrylhydrazyl radical ($IC_{50}=1.56{\mu}g/mL$) formation and exhibited a hydroxyl radical scavenging effect in the $Fe^{3+}-EDTA-H_2O_2$ deoxyribose system ($IC_{50}=2.7{\mu}g/mL$), and also inhibited the nonenzymatic lipid peroxidation of rat liver homogenate ($IC_{50}=13.5{\mu}g/mL$). The polar phase of the extract showed antioxidant activity. The oil showed antimicrobial activity against Streptococcus pneumoniae, Clostridium perfringens, Candida albicans, Mycobacterium smegmatis, Acinetobacter lwoffii and Candida krusei while the water-insoluble parts of the methanolic extracts exhibited slight or no activity. This study confirms that the essential oil of Ledum palustre L. possesses antioxidant and low antimicrobial properties in vitro.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.134-140
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• 2000

This study was performed to investigate the effects of n-3 fatty acids on renal function in male Sprague-Dawley rats of different ages 5-, 15- and 19-months old. The rats were fed a 20%(w/w) lipid diet containing 10% fish oil, compared with control animals fed a 20% lipid diet without fish oil for 4 weeks. The results were as follows: kidney weights were significantly higher in fish oil-fed rats compared to control rats. Plasma levels of total lipid, total cholesterol, and triglyceride markedly increased, with aging and LDL-cholesterol showing a significantly lower level in fish oil-fed rats than control rats. The urinary protein and glomerular filtration rate (GFR) increased with aging. GFR was higher in fish oil-fed rats. However, urinary protein was the same in the two groups. Renal medulla thromboxane B$_2$(TXB$_2$)tended to be lower in fish oil-fed 19-month-old rats. Urinary TXB$_2$and PGE$_2$were found to be higher proteinuria. Light microscopic examination showed interstitial inflammation, tubular atrophy, interstitial fibrosis and glomerular mesangium increase. Although glomerular sclerosis increased with aging, fish oil in the diet had no effect on histological changes. In conclusion, plasma lipid, urinary protein excretion and renal histological change showed a significant increase with aging. The reduction of TXB$_2$in the medulla and increase of GFR caused by fish oil indicated n-3 fatty acid could affect renal function in line with the hypolipidemic effect.

• Journal of the Korean Institute of Navigation
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• v.25 no.1
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• pp.33-44
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• 2001

Tankers have somewhat different shapes in construction and working condition compared with normal merchant ship. If an accident occurs, normal merchant ship's damages will mostly be confined to ship and cargo, but those of tankers will result in oil spills and catastrophic loss beyond our imagination. So, first we must understand risk factors, pre-loss control and post-loss control, legal regulations about its indemnification and marine insurance for oil tanker operation. When unexpected accidents happen, despite pre-loss control, it is possible to cover those kinds of losses by insurance. To control these losses, however, it is important to establish compensation for oil pollution and arrange for oil pollution preventing system. In spite of these oil pollution preventing systems, we have rarely seen that pollution from oil tankers could be solved. So this paper was studied more fundamental and overall control measures for the risk management of oil tanker operation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.555-558
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• 2008

For trying to frontal attack of new solution by fusion of technical tasks and conditions with it's solving methods of the essential tasks of marine resource development and environmental conservation in addition with elements of electronic high-technologies, the skimmer robot was proposed by using of oil spill disaster prevention and its disposal system with sequentially circular collection type of magnetic oil spill adsorbent powder and fabrics on the electronic barge robot for the scheme of sustainable development of environment-friendly technology. It was verified from the experiment of electronic barge robot demonstrator that the skimmer system of magnetic oil spill adsorbent powder and fabrics was very effective and useful technique to collect oil spill samples. At this point, the barge-based electronic remote control was very useful system operating easily on the marine fields to skim oil spill with dangerous toxic substances of crude oil and very harmful to human. Therefore, fusion technology proposed in this study combined with electronic and marine technology is the novel contributable technology for developing marine environmental conservation and environment-friendly disaster prevention, and also its management techniques.

• Journal of Microbiology
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• v.34 no.4
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• pp.363-369
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• 1996

As basic study to evaluate the treatability of oil-contaminated environment with bacteria, isolation and characterization of crude oil-degrading bacterium were carried out. A bacterial strain SH-14 capable of degrading crude oil was isolated from contaminated soils by enrichment culture technique and identified as Acinetobacter sp. by morphological, cultural and biochemical characteristics, and so named Acinetobacter sp. SH-14. The optimal medium composition and cultural conditions for the growth and emulsification of crude oil by Acinetobacter sp. SH-14 used were crude oil of 2.0%, $KNO_3$ of 0.2%, $K_2HPO_4$ of 0.05%, and $MgSO_4\;{\cdot}\;7H_2O$ of 1.0%, along with initial pH 7.0 at $30^{\circ}C$. Acinetobacter sp. SH-14 showed to be resistant to chloramphenicol and utilized various hydrocarbons such as dodecane, hexadecane, isooctane, cyclo-hexane etc., as a sole carbon source. Acinetobacter sp. SH-14 harbored a single plasmid. By agarose gel electrophoresis and curing experiment it was found that the genes for crude oil components degradation were encoded on the plasmid.

• Journal of the Korean Society of Combustion
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• v.20 no.1
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• pp.15-23
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• 2015

This paper presents the results of field demonstration for fuel switching to bio-fuel oil in 4 commercial heavy oil fired power plants. The 100% fuel switching field demonstration was successfully carried out in two tangential-firing boilers at a capacity of 75 and 100 MWe respectively without major equipment retrofit, and also 25% bio-fuel oil blending for two opposite firing boilers at a capacity of 350 and 400 MWe respectively. Despite the low density and heating value, the bio fuel was successfully replaced heavy fuel oil at the full load by only adjusting operational parameters. Incase of bio fuel oil combustion, heat absorption of radiative heat transfer section was reduced while convection section has opposite trend. In pollutants emission, a major reductionin SOx as well as 10-20% reduction in NOx were achieved by the fuels witching. On the other hand, boiler efficiency was slightly underestimated.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.3
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• pp.60-65
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• 2008

A typical louvered-fin oil cooler can be easily contaminated under dusty environment hence resulting in poor performance of a heat exchanger. Thus, in this study, a dust-proof oil cooler has been studied with a unique shape of a 3-dimensional wavy fin since non-louvered fins could have better performance under dusty environment compared to louvered fins. Recently, they have been introduced to commercial and constructional vehicles in Japan. At first numerical analysis has been done to optimize the angle of the wavy fin so that the oil cooler developed can satisfy the target performance. The wavy fin has been then made with roll-forming and roll-pitch stands, and a prototype of an oil cooler with the wavy fin has been finally built with brazing. The performance test showed that the heat release rate of the oil cooler was well beyond the target, 4.94kW and the air-side pressure drop was below the criterion, 0.19kPa. In addition, the results showed that the numerical prediction was effective enough to design the dust-proof oil cooler that satisfies the performance criteria.

• Tribology and Lubricants
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• v.24 no.6
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• pp.285-290
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• 2008

The purpose of this paper is to present the case study of tribological failure analysis on the gear damages, oil leakage, and sealant sealing in a manual transmission of front engine and front wheel drive vehicle. The manual transmission is to change the speed range and direction of the engines depending on the driving conditions by friction driving forces with input and output gear system. The material property and surface roughness of the gears are strongly related to the gear noise and micro-vibration, oil leakage and wear, which may decrease the real contact area of the gear and the strength of the oil film thickness between the driving gear and driven one. The O-ring damage of speedometer driven gear and bad sealant sealing of oil pan may produce oil leakage through the contact surfaces, which cause the oil shortage and seizure on the sliding surfaces of the transaxle gears. In the failure case study, the proper repair working and good lubrication are very important for the long life of the transaxle without any tribological failures and oil leakage.