• 한국기계연구소 소보
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• v.4 no.1
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• pp.89-97
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• 1981

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.5
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• pp.552-561
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• 2006

The single droplet combustion characteristics of diesel fuel and low quality oil with additive oxygenate and paraffin under high ambient temperature and atmospheric pressure were investigated in the study. The results of the study may are concluded as follows: In the combustion of diesel fuel and low quality oil droplet with additive of oxygenate and paraffin. the dimensionless droplet size of $(D/Do)^2$ was linearly decreased with time. A fuel droplet with low boiling temperature additives and in high boiling temperature base fuel evaporates and burns faster than usual base fuel. Especially. these trends were remarkably obtained by decreasing boiling point and increasing blending contents of additives in case of oxygenated agents rather than n-paraffin agents. This rapid burning may result from so-called 'micro-explosion' and its burning intensity varies with the types of additives. The results above may suggest that rapid evaporation of oxygenate additive in the middle stage of combustion can contribute much to combustion improvement of blended fuels.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.20-27
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• 2004

In the study, the effect of low boiling point oxygenates in high viscous fuels on the exhaust emissions has been investigated for a single cylinder DI diesel engine. It was tested to estimated change of engine performance and exhaust emission characteristics for the base fuels and low boiling point oxygenates blended fuel which have six kinds of fuels and various mixed rates. The results of the study may be con eluded as follows By blending of various low boiling point oxygenated agents to lower grade fuels, significant improvements were simultaneously obtained in smoke, CO, PM, SOF and BSEC. Especially, these trends were remarkably obtained by retarding injection timing, by decreasing boiling point and increasing blending contents of additives in case of oxygenated agents rather than non-oxygenated agents. Also, it was revealed that when 20 vol.％ DMM added to high viscosity fuels and injection timing was retarded, Nox-smoke trade off relationship was much better than that of ordinary diesel fuel. Thus, lower grade fuels with high viscosity could be expected to be used efficiently and cleanly in diesel operation by blending low boiling point oxygenates.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.291-297
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• 2006

Recently it is a tendency that the use of the heavy fuel oil is investigated even from the middle&small class vessel in order to reduce the operating cost of vessel caused by with rise of international gas price. In this study, analyzed the physical & chemical properties and examined the effect of refining treatment and a fuel oil additive for MF30 fuel oil which is a mixture fuel oil mixed M.G.O and the heavy oil MF380 use to be possible in the middle&small class vessel. As a results, the effects of two of pre-refinery treatment methods as centrifugal purifier and heating & homogenizing system(M.C.H) are some feeble, but the pour point and the flash point came to be low more or less. The effect of property improvement which is caused by with the fuel oil additive did not appear positively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.39-45
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• 2007

Recently it is a tendency that the heavy fuel oil is considered to be used on board even middle or small sized vessels in order to reduce the operating cost of vessel mused by a rise in international oil prices. In this study, analyzed the physical & chemical properties and examined the effect of refining treatment and a fuel oil additive for MF30 fuel oil which is a mixture fuel oil mixed M.G.O and the heavy oil MF380 use to be possible in the middle&small class vessel. As a results, the effects of two of pre-refinery treatment methods as centrifugal purifier and heating & homogenizing system(M.C.H) are some feeble, but the pour point and the flash point came to be low more or less. The effect of property improvement which is mused by the fuel oil additive did not appear positively.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.249-250
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• 2002

일본재첩(Corbicula japonica)은 부족강(Pelecypoda), 백합목(Veneroida), 재첩과 (Corbiculidae)에 속하는 종으로 우리나라에서 생산되는 재첩의 대부분을 차지하고 있으며, 전국적으로 건천을 제외한 대다수 하천의 하구역에 서식하고 있다. 우리나라의 재첩에 관한 연구는 주로 번식과 산란(이와 정, 1980; 권 등, 1987, 곽 2000; 김과 유, 2000a, 2000b; 김 등, 2002b)을 중심으로 일반적인 생태와 환경(정, 1977; 김 등, 2002a) 및 분류(조 등, 1998), 자원학적 조사(박과 이, 1968; 주와 김, 1982)와 저질의 선택성과 잠입(강과 양, 1999)을 중심으로 많은 연구가 수행되었으나 정확한 적정 염분과 세부적인 서식환경 및 생태에 관한 연구는 부족한 실정이다. (중략)

• The Korean Journal of Malacology
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• v.5 no.1
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• pp.35-41
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• 1989

Heaty metals in mollusks and in sedimints collected from five stations along Mangyong river area in Jeonra Bug Do were examined during 1988 through 1989. Concentration of heavy metals in Cipangopaludina chinensis malleata and Anodonta woodiana were highly correlated with that in sediments, And concentration of heavy metals in both of millusks and sediments from industrialized area was higher than the other stations. Above results suggested that Mangyong river was polluted with heavy metals and heavy metals were accumulated in molluscan soft bodies.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.3
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• pp.143-150
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• 2009

Fuel oil mostly used for a ship is made from crude oil by refining process. In order to produce plenty of high-quality fuel oil, the Fluid catalytic cracking(FCC) method is widely adopted to many refinery factories during the decomposition process from high molecule into lower molecule. The major constituents in spent FCC catalysts are Si, Al, Fe, Ti, alkali metals and some others. The spent catalyst is also composed small amounts of rare metals such as Ce, Nd, Ni and V. The big problem in FCC oil is mixing the catalyst in the oil. This reason is unstable separation of FCC catalyst in separator. Such a FCC catalyst will become a reason of heavy wear down in moving parts of engine. The impurity in oil is ash and deposit compound, such as Al, Si, Ni, Fe and V, which will accelerate the wear down on fuel pump, fuel injection valve cylinder liner and piston ring. It is important to find a basic reason of an engine trouble for preventing similar troubles anymore. Insurance compensation will be different according to the reason of an engine trouble which might be natural abrasion or other external causes. In this study, types and reasons of engine troubles related to fuel oil will be covered.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.1-5
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• 2009

This study was to investigate the habitat conditions and growth of right eye flounder (Kareius bicoloratus) in the Saemangeum Reseorvoir during 1995$\sim$2007. The planktonic larvae of K. bicoloratus appeared in early March, and then the juveniles started the benthic life in the tide-pools inside the reservoir, being 1.5$\sim$2.5cm in total length in early April and 6.0$\sim$7.2cm in mid-July. This species was not collected in the tide-pools after July, indicating that the juveniles began to move to outer seas for growing. When the tide barrier of Saemangeum was constructed, the juveniles of K. bicoloratus decreased as the tidal pools were covered continuously, then they could not be collected after 2005. Thus, it is concluded that the environmental change has taken important influence on distribution and spawning of K. bicoloratus since the reservoir was constructed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.658-665
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• 2013

In this study, we measured particulate matter(PM) which emerged as the hot issue from the International Maritime Organization(IMO) and the exhaust emission using HANBADA, the training ship of Korea Maritime University. In particular, the PM was obtained with TEM grid. PM structure was observed by electron microscopy. And exhaust gases such as NOx, $CO_2$, and CO were measured using the combustion gas analyzer(PG-250A, HORIBA). The results of this study are as follows. 1) When the ship departed from the port, the maximum difference in PM emissions were up to 30 % due to the Bunker Change. 2) Under the steady navigation, emission of PM was $1.34mg/m^3$ when Bunker-A is changing L.R.F.O(3 %). And, at the fixed L.R.F.O (3 %), emission of PM was $1.19mg/m^3$. When the main engine RPM increased up to 20 % with fixed L.R.F.O(3 %), emission of PM was $1.40mg/m^3$. When we changed to low quality oil(L.R.F.O(3 %)), CO concentration from main engine increased about 16 %. On the other hand, when the main engine RPM is rising up to 20 %, CO concentration is increased more than 152 percent. These results imply that the changes of RPM is a dominant factor in exhaust emission although fuel oil type is an important factor. 3) The diameter of PM obtained with TEM grid is about $4{\sim}10{\mu}m$ and its structure shows porous aggregate.