• Journal of the Society of Naval Architects of Korea
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• v.46 no.4
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• pp.398-408
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• 2009

Crude oil carriers or product oil carriers are confronted with sea pollution due to hull damage from various accidents. To reduce the oil spillage of tankers, IMO(International Maritime Organization) and OPA 90(Oil Pollution Act 1990) adopted the hull structures of double skin type. In this study, oil spillage test of the double skin tanker with 1/100 scaled model was carried out under damaged condition due to collision and grounding accidents. A new structural type of oil tanker was also tested with pipe and valve system arranged in double side and single bottom hulls. Their results were compared with that of conventional type double hull on the view point of ship safety and oil spillage.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.1
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• pp.85-93
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• 2019

Oil seals are most essential parts in mechanical lubrication system to maintain the close gaps between stationary and high rotating components, and to help prevent oil leakages. Oil seals also can prevent harmful contaminants entering from outside to machinery, especially in severe environments. Therefore, the oil seals have an important performance in the machinery components. The performance of the oil seals are influenced by the design variables such as amount of interference gap between the main lip and shaft, the angle of main lip at air and oil sides and the distance between the garter spring and main lip. In the present study, a finite element analysis was performed to evaluate the oil seal performance with the considerations of number of oil seal dust lips and angle of the lip at oil side with the different design variables. As a result from the FEM analysis, the stress and contact pressure distributions was derived, based on this, performance of the sealing and durability were determined.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.539-547
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• 2021

Indonesia is the largest exporter of palm oil in the world. The province of West Sulawesi is the second-largest palm oil producer in Indonesia. This study examines the contributions of oil palm farming to total household income and the factors affecting the household expenditure of oil palm smallholders in West Sulawesi, Indonesia. This study also identifies the problems related to oil palm production in the province. Primary data were collected from 174 oil palm smallholders using a standardized questionnaire in the Lariang sub-district, Pasangkayu, West Sulawesi, Indonesia. Several statistical tools were employed to analyze the data. The study estimated the average household income of the smallholders at IDR 30,417,441 per year, out of which 85,8% comes from oil palm farming, followed by non-oil palm farming (8%) and off farming (6.2%). On the other hand, the average household expenditure was found to be IDR 23,476,069 per year which 66% goes for food consumption and 34% for non-food consumption. The findings revealed that household expenditure of the oil palm smallholders is strongly and positively affected by a number of factors such as household income, education level, family size, earning members in the family, number of children attending school, and amount of credit taken by the household.

• Tribology and Lubricants
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• v.36 no.6
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• pp.307-314
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• 2020

In this paper, studies on application cases of machine condition monitoring using oil sensors are reviewed. Owing to rapid industrial advancements, maintenance strategies play a crucial role in reducing the cost of downtime and improving system reliability. Consequently, machine condition monitoring plays an important role in maintaining operation stability and extending the period of usage for various machines. Machine condition monitoring through oil analysis is an effective method for assessing a machine's condition and providing early warnings regarding a machine's breakdown or failure. Among the three prevalent methods, the online analysis method is predominantly employed because this method incorporates oil sensors in real-time and has several advantages (such as prevention of human errors). Wear debris sensors are widely employed for implementing machine condition monitoring through oil sensors. Furthermore, various types of oil sensors are used in different machines and systems. Integrated oil sensors that can measure various oil attributes by incorporating a single sensor are becoming popular. By monitoring wear debris, machine condition monitoring using oil sensors is implemented for engines, automotive transmission, tanks, armored vehicles, and construction equipment. Additionally, such monitoring systems are incorporated in aircrafts such as passenger airplanes, fighter airplanes, and helicopters. Such monitoring systems are also employed in chemical plants and power plants for managing overall safety. Furthermore, widespread application of oil condition diagnosis requires the development of diagnostic programs.

• Korea Trade Review
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• v.47 no.3
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• pp.141-156
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• 2022

This study intends to examine the regional blocs of the international crude oil futures market by analyzing the dynamic conditional correlation between the international crude oil futures markets using the DCC-GARCH model. For statistical data, from April 2, 2018 to March 31, 2022, international crude oil futures prices such as Europe, the United States, China, and Dubai were used. To summarize the results of the study, first, the phenomenon of regional blocs in the international crude oil futures market is occurring, and it is found that it is gradually strengthening as time goes by. Second, it was found that the dynamic correlation of the international crude oil futures market is temporarily strengthened when a supply-demand imbalance problem occurs due to a global shock. Third, it was found that the volatility of the Chinese crude oil futures market affects the international crude oil futures market. This study confirmed that the regional blocs phenomenon in the international crude oil futures market is strengthened as time goes by. In particular, it suggested that China's influence in the international oil market would increase.

• The Journal of the Convergence on Culture Technology
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• v.4 no.3
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• pp.93-98
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• 2018

The article studies macroeconomic effects of the oil shock for Korea, which is a representative emerging economy of Asia and a small open economy. This article analyzed the macroeconomic effects of oil shocks in terms of demand and supply. In the case of Korea, oil price shocks different responds depending on factors of shock. Oil supply shock have led to a decline in industrial activity and interest rate, and oil specific demand shock have shown the greatest increase in interest rate relative to other oil price shocks. In addition, oil demand shock driven by economic activity showed that the comsumer price and the exchange rate are the largest compared to the oil shock caused by other factors. Therefore, policy makers will need to identify the source of the oil shock.

• Journal of Life Science
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• v.14 no.3
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• pp.453-458
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• 2004

Soybean oil and protein contents are very important as a nutritional component of food. The seed composition as oil and protein are polygenic traits. In this study, the Keunolkong${\times}$Iksan10 populations were evaluated with SSR markers to identify QTLs related to oil and protein contents. Three related independent QTLs near the marker satt100 on LG C2, satt546 on LG D1b＋W and satt418 on LG L were identified oil contents. The three independent QTLs near the marker satt556 on LG B2, satt414 on LG J and satt238 on LC L were identified of protein contents. In the results of this study, common QTLs on LG L was associated with seed oil and protein contents. In the result of this study, it is believed that the seed composition material as oil and protein contents were mainly controlled by environmental stresses and they are seed size on genotypes.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.254-259
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• 2011

Growing evidence indicates that oxidized low density lipoprotein (LDL) may promote atherogenesis. Therefore, inhibition of LDL oxidation may impede this process. The inhibitory effected on the susceptibility of human LDL to $Cu^{2+}$ or macrophages induced oxidation was investigated by monitoring thiobarbituric acid reactive substances(TBARS). Organosulfur compounds of garlic oil contains diallyldisulfide, diallyltrisulfide, diallyltetrasulfide, and diallyl pentasulfide in order. Garlic oil inhibited LDL oxidation by $Cu^{2+}$, or macrophages in a dose dependently, with a 20~60 ${\mu}g$, as increased TBARS assay. Garlic oil, at 60 ${\mu}M$, almost completely inhibited macrophages induced increase in electrophoretic mobility of LDL. When compared with several other antioxidants, probucol showed highest ability, and then garlic oil showed a much higher ability than natural occurring antioxidants, ${\alpha}$-tocopherol and ascorbic acid. The results suggested that garlic oil might play the inhibitory effects in the process of LDL oxidation.

• Journal of Biosystems Engineering
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• v.2 no.1
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• pp.1-6
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• 1977

The dilution of crankcase oil with unburned portions of the fuel during operating is one source of the oil contaminations which will reduce engine life.It has been learned that major causes of oil dilution may be the result of using impure fuels which were mixed with water, dust, and some others, but very little was known about this. This study was conducted to develop a more intimate understanding about oil dilution of the farm kerosene engine while using impure fuel mixed with expecially diesel. Fuels being used in this study were 9 kinds of mixed fuels, kerosene and diesel. Farm kerosenen engine of 10 P.S. was tested at no-load of 1000 and 2000 rpm., such as 1/4, 2/4, 3/4, 4/4, and 11/10 loads for understanding about oil dilution of keresene engine.The result of this study are summarized as follows : 1. The amounts of oil dilution of the engine being tested was increased with increase in the applied loads and the contents of diesel in the mixed fuels when using fuels other than kerosenen and diesel, whereas at $D_100$ fuel the comount of oil dilution decreased in some cases. The lowest value was measured to be 20 cc/hr, at $K_90$ fuel of no-load condition, and the highest value to be 293cc/hr. at $K_{10}$ fuel of 4/4 load condition. 2. When the engine was operated at no-load condition, the amount of oil dilution at 100rpm. was much more than at 2000 rpm. 3. Because the fuel consumption and the oil dilution showed a similar tendency along the applied loads, the excessive fuel consumption of engines was supposed to be one of the important factors affecting oil dilution. 4. The temperature of crankcse oil was varied invesely with oil dilution, but they were not thought to be factors to determine each other variable. 5. The tested engine could be operated with high percentage of diesel mixed fuel from no-load condition to fully loaded condition, but it would be impossible to operate the engine for long hous continuously due to excessive speed fluctuation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1163-1168
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• 2011

Most transformers use insulating and cooling fluids derived from petroleum crude oil, but mineral oil has some possibility of environmental pollution and fire with explosion. vegetable oil fluids extracted from seed has superior biodegradation and fire-resistant properties including an exceptionally high fire point enhancing fire safety. In this study, it is aimed at the practicality of substituting natural ester dielectric fluid for mineral oil in liquid insulation system of transformers. As a rise in coil winding temperature has a direct influence on transformer life time, it is important to evaluate the temperature rise of coil winding in vegetable oil in comparison with mineral oil. Four transformers for the test are designed with 10KVA, 13.2KV, one phase unit. The temperature are directly measured in insulating oil of these transformers with the two sorts of natural ester and mineral oil dielectric fluid respectively. Experiment for aging carry out two means. First means remained $120^{\circ}C$ that transformer of mineral oil were operated at 185% load. Second means is that insulating oils of two natural ester and mineral oil were aged by thermal cycles repeating from $30^{\circ}C$ to $120^{\circ}C$. For the heating, Transformers were operated at 185% load. For the cooling, cooling system was operated in the chamber. Samples were analyzed at 42, 63, 93, 143, 190, 240 300cycles. Analysis contents are dielectric strength, total acid value. Mineral oils compared results of first means with results of second means. And compared two sort natural esters respectively with mineral oil in second means.