• Journal of Navigation and Port Research
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• v.43 no.2
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• pp.134-141
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• 2019

The objective of this study was to establish whether global macroeconomic indicators affect the profitability of Korean shipping companies by using panel regression analysis. OROA (operating return on assets) and ROA (ratio of net profit to assets) were selected as proxy variables for profitability. OROA and ROA were used as dependent variables. The world GDP growth rate, interest rate, exchange rate, stock index, bunker price, freight, demand and supply of the world shipping market were set as independent variables. The size of the firm was added to the control variable. For small-sized firms, OROA was not affect by macroeconomic indicators. However, ROA was affected by variables such as interest rates, bunker prices, and size of firms. For medium-sized firms, OROA was affected by demand, supply, GDP, freight, and asset variables. However, macroeconomic indicators did not affect ROA. For large-sized firms, freight, GDP, and stock index (SCI; Shanghai Composite Index) have an effect on OROA. ROA was analyzed to be influenced by bunker price and SCI.

• Cement
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• s.17
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• pp.43-58
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• 1966

• Cement
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• s.10
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• pp.46-48
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• 1965

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.05a
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• pp.185-188
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• 2019

In this paper, the towing stability of the LNG bunker barge is estimated. Currently, LNG bunkering barge is being developed as an infrastructure for the bunkering of LNG (Liquefied Natural Gas), an eco-friendly energy source. Since the LNG bunker barge are in the form of towed ship connected to the tow line, the towing stability of the LNG bunker barge is very important for the safety of not only the LNG bunker barge but also the surrounding sailing vessels. The numerical code for towing simulation was developed to estimate the towing stability of the LNG bunker barge at the initial design stage. The MMG(Manoeuvring Mathematical Group) model was applied to the equations of motion and the empirical formula was applied to the maneuvering coefficients so that they could be used in the initial design stage. To validity of the developed numerical code, it was compared with published calculation and model test results. Towing simulations were carried out according to with and without stern skeg of the LNG bunker barge using the developed numerical code. Through the results of the simulations, the appropriateness of the stern skeg area designed was confirmed.

• Journal of the Korean Chemical Society
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• v.11 no.1
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• pp.17-21
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• 1967

For utilization of Bunker-C residual oil produced at KOCO., the auther tested the properties of vacuum fraction and blown asphalt, and as the result of it, (1) Vacuum fraction had so broad range of viscosity and high flash point that could be produced all kind of lublicating oil, but had to be dewaxed for high pour point, (2) Urea dewaxing was suitable to lighter fraction but not to heavier fraction, so, for heavier fraction, solvent dewaxing was needed. (3) Blown asphalt produced from vacuum residue had uniform relation between softening point and penetration in spite of broad change of blowing condition and adding of catalyst.

• Journal of the Korean Professional Engineers Association
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• v.45 no.6
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• pp.54-57
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• 2012

Usually the combustion of Bunker-C oil limited in a special area and achieved certain clean air effect. Water added oil combustion has the ability enhance the effect by the Overall Heat Transfer Coefficient. Every water adding step dedicated to reach an increase of the heat transfer effect. So, we can use this system and achieve reasonable energy consumption.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.8
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• pp.458-464
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• 2015

Total petroleum hydrocarbon (TPH) removal and temperature variations in bunker fuel oil C contaminated soil were investigated by using microwave radiation in the presence of triiron oxide or activated carbon as a heating element. Temperature increments of $1.4{\sim}1.6^{\circ}C/Watt$ were observed, when 100~500 watt of microwave radiation was applied for the contaminated soil in the presence of triiron oxide or activated carbon. Temperature variation of the soil was more rapid in the presence of triiron oxide than activated carbon. 10% or 25% of heating element content was required to reach the temperature of thermal desorption for triiron oxide and activated carbon respectively. After radiation, 44.1% and 89.4% of initial TPH in soil was removed in the presence of triiron oxide and activated carbon respectively. It was observed that activated carbon was more reactive than triiron oxide for the removal of high molecular carbon of bunker fuel oil C.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.51-59
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• 2007

The waste bunker usually consists of waste entrance zone and waste pit. In this paper, the distributions of air flow, $NH_3$ concentration and $H_2S$ concentration in a waste bunker were investigated to prevent an odor generated in a waste pit from dispersing to the waste entrance zone by numerical method. Four cases were considered such that 1) the waste incinerators is operated, 2) the waste incinerators is stopped, 3) the waste incinerator is operated and the direction of a supply diffuser is $45^{\circ}$ upward, 4) the waste incinerator is stopped and the direction of a supply diffuser is $45^{\circ}$ upward. In case of 1), the fresh air from the waste entrance zone is exhausted smoothly to the main exhaust grill of the waste pit. It means that an odor dispersion to the waste entrance zone will not occur. However in case of 2), the induction of fresh air is so small and the supply air with an odor in waste pit can flow to the waste entrance zone. Therefore, an odor will be dispersed to the waste entrance zone. This paper shows the solution that the supply diffuser with the direction of $45^{\circ}$ upward is chosen. As a result in case of 3) and 4), an odor dispersion to the waste entrance zone does not occurred and on odor is exhausted smoothly to the auxiliary exhaust grill.

• KSBB Journal
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• v.15 no.1
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• pp.27-34
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• 2000

A marine bacterium having a high oil-degrading activity was isolated form the oil-polluted southern sea of Korea, and was identified as Pseudomonas aeruginosa and was named Pseudomonas aeruginosa BYK-2. The optimal tmeperatur, culture time, pH and NaCl concentration for biosurfactant production and cell growth showed $25^{\circ}C$, 48h, 7.0 and 0%(w/v), respectively. After cultivation at $25^{\circ}C$, 180 rpm in 250 mL erlenmeyer flask for 7days, 1%(w/v) arabian light crude oil and bunker C oil which are considered to be hardly degradable compounds were degraded 92.1%(w/w) and 76%(w/w) respectively. And then, cell adherence was measured on various carbon sources. The cell adherence indicated over 80% on hydrocarbons(arabian light crude oil, kuwait curde oil, bunker C oil, n-paraffine, n-hexadecane, n-tetradecane) as carbon sources. Lecithin among fatty acids(oleic acid, olive oil, lecithin) showed highest cell adherence of 91.5%. The cell adherence of sugars(arabinose, trehalose, dextrose, galactose, lactose, fructose, maltose, sorbitol, sucrose) observed to be less than 70% except for arabinose, galactose, sorbitol and sucrose.

• 한국해양학회지
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• v.26 no.4
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• pp.350-357
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• 1991

An experimental approach was applied to test the effects of stranded oils and dispersant cleanup on marine gastropods, Nodilittorina exigua, littorina brevicula and Purpura clavigera. They were exposed to Labuan crude, Dubai crude and Bunker C fuel oil. Direct oil contact caused death of gastropods within 96 hours. N. exigua and L. brevicula were more sensitive than P. clavigera at the exposure of Bunker C fuel oil. Toxic effects of Bunker C oil was slower than crude oils. direct contact to concentrated dispersant killed gastropods, while clean-up with diluted dispersant still gave severe damage. P. clavigera could escape from dispersed crude oil below 250 ppm. Oiling and dispersant clean-up may have severe effects on marine gastropods by rendering them washed out to sea.