• The Journal of Engineering Geology
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• v.9 no.1
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• pp.17-29
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• 1999

There are three major processes to impact the groundwater flow near underground storage caverns in the coastal area; effect of topography, effect of sea water intrusion, and effect of excavation. In this paper, the effects of three items were numerically studied to identify the major cause for altering the flow pattern. It turned out that the excavation is the most significant effect on the groundwater flow system. The groundwater pressure distributions and consequent groundwater pathways were significantly altered near the openings. By increasing the groundwater pressures from water curtain holes, the potential leakage of storage cavern was properly prevented

• 한국해양학회지
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• v.21 no.4
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• pp.203-210
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• 1986

A linear parallel transport model is formulated and applied to an idealized Yellow Sea, With this simple analytical model, the hither-to suspected upwind flow phenomena in the southern Yellow Sea can be reasonably explained. In deep waters where the local depth exceeds a critical depth (Hc=53m in the present model sea), pressure gradient force dominates over wind stress and contributes to an upwind flow. The estimated upwind flow velocity increases with wind speed and a maximum upwind flow occurs along the axis of the Yellow Sea embayment. For the typical south wind of 5-10 knots in summer, the upwind (southward) flow velocity along the axis of the Yellow Sea is estimated to be 1-5cm s$\^$-1/. While, for the typical north wind of 10-15 knots in winter, the upwind (northward) flow velocity is 5-12cm s$\^$-1/. These velocity ranges can be served as rough estimates for the intrusion velocity of the Yellow Sea Bottom Cold Water in summer and the Yellow Sea Warm Current in winter, respectively.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.1-9
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• 1999

This paper described the results of the characteristics of the near-bottom flow and field analysis of the tidal flats sediment. It was the aim of this paper to grasp current flow of tidal flat's environment and influence factor for environmental change forecast of tidal flats. Field measurement of water velocity, water elevation, bed materials test, and temperature distribution of tidal flat were conducted. Thereafter, current flow, turbidity and temperature distribution of tidal flat sediment have been discussed. The field research results showed that the fluctuating velocity near the seabed before and after its appearance at low tide was strongly affected by the wind wave. The resuspension of the sea-bottom sediment took place with great intensity before and after the appearance of the seabed at low tide. Both the sea water level and the weather condition were a significant influential factors. Such as, temperature and turbidity just on the surface and the shallow layer of seabed sediments were varied largely with time and weather conditions, but that its deeper layers was almost constant. Temperature on the seabed sediments was strongly influenced by irradiance and water depth. The temperature variation of the tidal flat and the variation characteristics of the current flow and turbidity depend greatly on the inhabiting environment of the tidal flat benthic organism.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.1-7
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• 2011

This study was accomplished to evaluate the performance of Multi Effect Distillation(MED) for solar thermal desalination system. It was designed Multi effect distillation with $3m^3$/day capacity and Shell&Tube type heat exchanger. Also, The effective heat transfer of Shell&Tube heat exchanger was used Cu(90%)-Ni(10%) corrugated tube. The parameters relating to the performance of Multi Effect Distillation are known as hot water flow rate. The experimental conditions for each parameters were $18^{\circ}C$ for sea water inlet temperature, $6m^3$/hour sea water inlet volume flow rate, $75^{\circ}C$ for hot water inlet temperature, 2.4, 3.6, and $4.8\;m^3$/hour for hot water inlet volume flow rate, respectively. The results are as follows, Development for Multi effect distillation was required about 40kW heat and 35kW cooling source to produce $3m^3$/day of fresh water. Based on the results of this study, It makes possible to secure economics of desalination system with solar energy which is basically needed development of high efficiency fresh water generator.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.227-233
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• 1999

This study is mainly concerned with phenomenon of cavitation-erosion on the several materials and corrosive liquids which were applied with vibrator (suggested by ASTM G-32, 20KHZ, 24{$mu}m$).The main results obtained are summarized as follows ; (1) The maximum erosion rate by cavitation erosion in both of fresh-water and sea-water appeared to be proportioned to their hardness and tensile strength. (2) Cavitation weight loss and rate of cast iron in sea-water condition were greater (approximately 3 times) than that in distilled-water condition, however in case of stainless and brass the cavitation weight loss and their rates were not so different in both of their conditions. (3) Cavitation weight loss of composite materials were shown as below on this test, DuraTough DL : Weight loss in sea-water condition were greater (approximately 2.3 times) than it's fresh-water condition. (4) As the result of observation with digital camea of specimens, the main tendency of cavitation erosion for metals, was that small damaged holes causing by cavitation e개sion was appeared with radial pattern, and composites materials was that small damaged holes were appeared randomly.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1403-1415
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• 2011

To understand the transport of anchovy egg-larvae, an integrated model consisting of a hydrodynamic model and a three-dimensional Lagrangian diffusion model was used for the anchovy Engraulis japornicus egg-larvae trace. Fist, in order to determine the circulation characteristics of the South Sea of Korea, residual flow according to tide, density and wind effect was investigated. In offshore regions, tide-induced residual current tends to flow eastward during the spring tide and westward during the neap tide. Residual flow is irregular due to the bottom topography in the coastal area. No special tendency was apparent in the open sea. Especially, the flow in the offshore regions showed results similar to that of the Tsushima Warm Current. The transport of anchovy egg-larvae is decided the physical properties of sea water. It is estimated that anchovy eggs spawned near the Jeju Island travels offshore, rather than to coastal areas, and grow in the front area between the coastal sea and offshore regions.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.74-79
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• 2011

This study was accomplished to evaluate the performance of Multi Effect Distillation(MED) for solar thermal desalination system. It was designed Multi effect distillation with $3m^3/day$ capacity and Shell&Tube type heat exchanger. Also, The effective heat transfer of Shell&Tube heat exchanger was used Cu(90%)-Ni(10%) corrugated tube. The parameters relating to the performance of Multi Effect Distillation are known as hot water flow rate. The experimental conditions for each parameters were $18^{\circ}C$ for sea water inlet temperature, $6m^3/hour$ sea water inlet volume flow rate, $75^{\circ}C$ for hot water inlet temperature, 2.4, 3.6, and $4.8m^3/hour$ for hot water inlet volume flow rate, respectively. The results are as follows, Development for Multi effect distillation was required about 40kW heat and 35kW cooling source to produce $3m^3/day$ of fresh water. And, Performance ratio of Development Multi effect distillation was about 2.0191.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.612-621
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• 2011

The influences of inland pollution sources because of rainfall events on the bacteriological water quality in Geoje Bay, a major shellfish production area in Korea, were investigated. The sanitary status of sea water and shellfish after rainfall events was also evaluated. The flow rates of 13 streams around Geoje Bay showed 6 to 7-fold increases after 15 to 21 mm of rainfall. Peak pollution was observed in the Naegan Stream, the Gandeok Stream and the Seojeong Stream. The calculated impact area of inland pollution sources was 3.1 $km^2$ immediately after 15 mm of rainfall and expanded to 3.5 $km^2$ after 24 hours. These calculations of impacted area matched results from fecal coliform analyses with sea water. The distance between the major pollution source in the bay (the Gandeok Stream) and the station with the worst bacteriological water quality immediately after 15 mm of rainfall, which was below the Korean standard, was 0.8 km in a straight line; this distance increased to 2.0 km after a period of 24 hours. The area impacted by inland pollution sources after a 15 mm rainfall event was wider than after a 21 mm rainfall. Although the flow rate from inland pollution sources was higher, the concentration of fecal coliform in the discharged water was lower after higher rainfall events. These observations corresponded with the results of fecal coliform analyses with sea water samples. According to the evaluation of the influences of inland pollution sources and fecal coliform analyses on sea water and shellfish samples in Geoje Bay, pollutants from inland sources did not reach the boundary line of the shellfish growing area after rainfall events of 15 or 22 mm. The bacteriological water quality of the shellfish growing area in Geoje Bay met the Korean standard and US NSSP requirements for approved shellfish growing areas.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.288-291
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• 1988

We have veen already reported the distribution of PSP of bivalve mollusca in southern coast of Korea and also analyzed their characteristics. The purpose of this study was to develop detoxification method for PSP infested sea mussel, Mytilus edulis, by rearing methods or processing treatments. There was no significant detoxification effect when the PSP infested sea mussel was reared in a tank with water recirculation system, but the toxicity of sea mussel rapidly decreased during the rearing time in a water flow system with filtered water. The detoxification rate of PSP during the rearing for 5 days in a water flow system tank with $15-17^{\circ}C$ of sea water was $94\%$ in case of high toxic sample with more than $2,600{\mu}g/100g$ and about $40\%$ in case of low toxic sample with less than $100{\mu}g/100g$. The toxicity of PSP extracted from the sample with 0.1N/ HCl solution was about 2-5 times higher than that extracted with distilled water. When sea mussel contained $100-150{\mu}g-PSP$ per 100g of edible meat was boiled for 30 min with tap water, the toxicity was destroyed as the level of PSP undetected by mouse assay. We can suggest that boiling of sea mussel with tap water was one of the most significant detoxification methods, but it was not enough to be safe in case of extremely high intoxicated sea mussel with PSP. For example, the digestive gland of sea mussel contained more than $9593{\mu}g/100g$ was heated in a can with tap water at $116^{\circ}C$ for 65 min. the residual PSP was more than $170{\mu}g$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.5
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• pp.297-302
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• 1988

We have veen already reported the distribution of PSP of bivalve mollusca in southern coast of Korea and also analyzed their characteristics. The purpose of this study was to develop detoxification method for PSP infested sea mussel, Mytilus edulis, by rearing methods or processing treatments. There was no significant detoxification effect when the PSP infested sea mussel was reared in a tank with water recirculation system, but the toxicity of sea mussel rapidly decreased during the rearing time in a water flow system with filtered water. The detoxification rate of PSP during the rearing for 5 days in a water flow system tank with $15-17^{\circ}C$ of sea water was $94\%$ in case of high toxic sample with more than $2,600{\mu}g/100g$ and about $40\%$ in case of low toxic sample with less than $100{\mu}g/100g$. The toxicity of PSP extracted from the sample with 0.1N/ HCl solution was about 2-5 times higher than that extracted with distilled water. When sea mussel contained $100-150{\mu}g-PSP$ per 100g of edible meat was boiled for 30 min with tap water, the toxicity was destroyed as the level of PSP undetected by mouse assay. We can suggest that boiling of sea mussel with tap water was one of the most significant detoxification methods, but it was not enough to be safe in case of extremely high intoxicated sea mussel with PSP. For example, the digestive gland of sea mussel contained more than $9593{\mu}g/100g$ was heated in a can with tap water at $116^{\circ}C$ for 65 min. the residual PSP was more than $170{\mu}g$.