• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1252-1258
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• 2022

The exhaust gas from the marine engines include a quantity of water vapor and particulate matter. The total particulate matter includes filterable particulate matter (FPM) and condensable particulate matter (CPM) that condense after releasing into the atmosphere. The portion of CPM is higher than that of FPM that is removable through the filter before discharging. An experimental setup for waste heat and water recovery and removal of CPM in the exhaust gas was tested using an industrial gas boiler in the laboratory. The water and CPM in the exhaust gas were removed through the first stage of cooling method and further removed through the second stage of absorption method. The efficiencies of water recovery were 73% after the first stage of cooling method and 90% after the second stage of absorption method. At the same time, the CPM was removed by 80-90% through the processes. The waste heat recovered could be used to process heat, and the water recovered could be used to process water in the ship. Furthermore, the CPM, which is a major source of the particulate matter but not subject to administrative regulation, could be removed effectively.

• Journal of the Korean earth science society
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• v.35 no.4
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• pp.249-258
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• 2014

Despite the greenhouse gases like carbon dioxide have steadily increased in atmosphere, the overall trend of the global average surface air temperature has stalled during the last decade (2002-present). This phenomenon is often called hiatus or warming pause, which is challenging the prevailing view that anthropogenic forcing causes warming environment. Our study characterized the hiatus by analyzing the HadGEM2-AO (95 yrs) simulation data based on RCP8.5 scenario. The PC2 time series from the EOF of the zonal mean vertical ocean temperature has been defined as the index that represents the warming pause. The relationship between the hiatus, ENSO and the changes in climate system are identified by utilizing the newly defined PC2. Since the La Nina index (defined as the negative of NINO3 index) leads PC2 by about 11 months, it may be possible that the La Nina causes the warming to be interrupted. We also show that the cooling of the climate system closed tied to the heat penetration into the deep ocean, indicating the weakening the warming rate is due to the oceanic heat uptake. Finally, the global warming hiatus is characterized by the anomalous warming in Arctic region as well as the intensification of the trade wind in the equatorial Pacific.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.1074-1081
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• 2021

Nitrous oxide (N₂O) is one of the six major greenhouse gases and is known to produce a greenhouse ef ect by absorbing infrared radiation in the atmosphere. In particular, its global warming potential (GWP) is 310 times higher than that of CO₂, making N₂O a global concern. Accordingly, strong environmental regulations are being proposed. N₂O reduction technology can be classified into concentration recovery, catalytic decomposition, and pyrolysis according to physical methods. This study intends to provide information on temperature conditions and reaction time required to reduce nitrogen oxides with cost. The high-temperature ranges selected for pyrolysis conditions were calculated at intervals of 100 K from 1073 K to 1373 K. Under temperatures of 1073 K and 1173 K, the N₂O reduction rate and nitrogen monoxide concentration were observed to be proportional to the residence time, and for 1273 K, the N₂O reduction rate decreased due to generation of the reverse reaction as the residence time increased. Particularly for 1373 K, the positive and reverse reactions for all residence times reached chemical equilibrium, resulting in a rather reduced reaction progression to N₂O reduction.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.122-123
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• 2000

일반적으로 고형물을 함유하는 통조림 제조에 있어 고형물을 캔에 충진할 경우 물이나 시럽, 조미액 및 식용유 등 Packing medium을 첨가하는데 이 Packing medium 을 첨가하는 목적은 관내의 조미가 가능하고 가열살균하는데 대류전열의 매체로 작용하며 관내에 봉입되는 공기량을 줄일수 있고 관충격에 대하여 완충작용을 하는 역할이 있기 때문이기는 하나 관의 중량이 무겁게 되고 가용성 성분의 희석, 흡수와 팽윤에 따른 육질의 연화 등 단점이 되기도 한다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.350-351
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• 2001

황토는 주로 규소(Si)와 알루미늄(Al)을 포함하는 각종 점토와 철(Fe) 및 기타 미량 금속을 포함하는 불순물로 구성된 금속산화물로서 분해력, 자정력, 흡수력, 원적외선 방사력, 생약성(해독력 및 항균력)등을 나타내고 있어 오래 전부터 수(水) 처리 과정에서 무기흡착제로 이용되어 오고 있으며, 토양개량제, 의약 및 식용, 환경 정화제와 축산, 적조 제저제에 이르기까지 다양하게 이용되어 오고 있다. (중략)

• 한국해양학회지
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• v.21 no.4
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• pp.193-202
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• 1986

Spatio-temporal variabilities of seawater temperature at 0 and 30m in the southeastern Hwanghae were studied by variance and empirical orthogonal function(EOF) analysis of long records of temperature between 1967 and 1982. The spatial distribution of monthly mean sea surface temperature has a pattern similar to the long-term annual mean which decreases from south to north. On the contrary, the total variance computed from the annual mean of sea surface temperature(SST) increases from south to north. The variance of SST is found to be two times greater than that at 30m in the study area except coastal area south of Kyunggi Bay. The important variance of temperature seem s to be closely associated with the seasonal change of temperature because the first and second modes of EOF having a seasonal cycle explain 97.6% and 85.2% of variances at 0 and 30m, respectively. There is a large difference in temperature between the northern and southern parts of the study area during winter, while the difference becomes very small during summer. This might reflect that in summer the heat gain of sea surface from the incoming radiation is much more important than the heat loss or the oceanic heat advection. In summer coastal waters south of the Kyunggi Bay and around Mokpo are observed to be colder than offshore waters due to tidal mixing.

• 한국해양학회지
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• v.30 no.2
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• pp.91-115
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• 1995

Air-sea heat fluxes in the East Sea were estimated from the various ship's data observed from 1961 to 1990 and the JMA buoy #6 data from 1976 to 1985. The oceanic heat transport in the sea was also determined from the fluxes above and the heat storage rate of the upper layer of 200m from the sea surface. In winter, The incoming solar radiation is almost balanced with the outgoing longwave radiation. but the sea loses her heat through the sea surface mainly due to the latent and sensible heat fluxes. The spatial variation of the net surface heat flux is about 100 Wm/SUP -2/, and the maximum loss of heat is occurred near the Tsugaru Strait. There are also lots of heat losses in the southern part of the East Sea, Korea Strait and Ulleung Basin. Particularly, the heat strong loss in the south-western part of the sea might be concerned with the formation of her Intermediate Homogeneous Water. In summer, the sea is heated up to about 120∼140 Wm/SUP -2/ sue to strong incoming solar radiation and weak turbulent heat fluxes and her spatial variation is only about 20 Wm/SUP -2/. The oceanic heat flux is positive in the southeasten part f the sea and the magnitude of the flux is larger than that of the net surface heat flux. This shows the importance of the area. In the southwestern part of the sea, however, the oceanic heat flux is negative. This fact implies cold water inflow, the North Korean Cold Water. The sigh of net surface heat flux is changed from negative to positive in March and from positive to negative in September. The heat content in the upper surface 200 m from the sea surface reaches its minimum in March and maximum in October. The annual variation of the net surface heat flux is 580 Wm/SUP -2/ in southwestern part of the sea. The annual mean values of net surface heat fluxes are negative, which mean the net heat transfer from the sea to the atmosphere. The magnitude of the flux is about 130 Wm/SUP -2/ near the Tsugaru Strait. The net surface fluxes in the Korea Strait and the Ulleung Basin are relatively larger than those of the rest areas. The spatial mean values of surface heat fluxes from 35$^{\circ}C$ to 39$^{\circ}$N are 129, -90, -58, and -32 Wm/SUP -2/ for the incoming solar radiation, latent hear flux, outgoing longwave radiation, and sensible heat flux, respectively.

• Journal of Navigation and Port Research
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• v.46 no.4
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• pp.297-302
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• 2022

An exothermic oil absorbent sheet with calcium chloride crystals can be fabricated, by dipping a clean polypropylene fabric in calcium carbonate and hydrochloric acid solution and drying it. The exothermic oil absorbent sheet applied to the seawater surface, releases heat by the dissociation of calcium chloride. The dissociation heat liquefies the solidified low-sulfur fuel oil at a low temperature, and converts it to a state at which it can be absorbed. The optimum mole concentrations of calcium carbonate and hydrochloric acid required for the exothermic oil absorbent sheet, are 0.25 M and 0.5 M, respectively. The oil absorption capacity of the exothermic oil absorbent sheet for low sulfur fuel oil depends on the seawater temperature. But, it is highly excellent at 4.5-7.08 g/g at 10℃, the average seawater temperature during the winter in Korea. The exothermic oil absorbent sheet is an excellent alternative in absorbing low-sulfur fuel oil in winter and removing it from seawater.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.898-905
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• 2019

As the positive feedback between the absorption of chromophoric dissolved organic matter (CDOM) and acceleration of ice melt can impact the aquatic biota and dynamic heat budget, long-term monitoring of the CDOM variation in the polar ocean is necessary. However, the monitoring of CDOM is not easy because of harsh weather and difficult access, especially in the Antarctic Ocean. Therefore, the purpose of this study was to find a suitable long-term monitoring site for CDOM variation; we selected Maxwell Bay and Marian Cove at Sejong Base and horizontal and vertical distributions of CDOM were measured. After a 72 hr time-series measurement test of the CDOM variation at Sejong Dock and Sejong Cape in Maxwell Bay, Sejong Dock was selected, as it does not haveland discharge effects. The seasonal variation of CDOM was evident and the average CDOM concentration of Maxwell Bay was comparable with the adjacent sea. The CDOM at Sejong Dock from February to November 2010 was the highest in the fall and winter and the lowest during spring and summer. Thus, based on our one-year CDOM data, we suggest that Sejong Dock in Maxwell Bay is suitable for long-term monitoring of CDOM as an indicator of photochemical and biological environmental change and an important factor in determining the heating budget in the Antarctic Ocean.

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.185-189
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• 2008

This study was conducted to find out the effects of relationship between ocean conditions and snowfall when cold and dry continental air mass passes through the West Sea of Korea. Route of continental high atmospheric pressure can cause effect on snowfall at the west regions (Inchoen, Gunsan, Mokpo) of the Korean Peninsula. The continental high atmospheric pressure extend from the southern China to western coastal region of the Korean Peninsula during the December, and it extend from the north side of China through Bohai Sea and Yodong Peninsula to central area of the Korean Peninsula during the February. Therefore, more snowfall recorded in Incheon is higher during Feb. than Dec.. whereas Gunsan and Mokpo is the opposite. The heavy snowfall at the western coastal region of Korea was caused by loss of the heat from the ocean to air when it's higher than $100W/m^2$. the heavy snowfall was also observed when the arrangement of continental high atmospheric pressure and low pressure was high at the West and low at the East, which formed a front in West and when the wind blow from the North or North West at the speed of $4\sim8m/sec$. There were not much relation between salinity in the western sea and snowfall in the western coastal region of Korea.