• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.87-94
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• 2009

Surfactant-enhanced air sparging (SEAS) was developed to suppress the surface tension of groundwater prior to air sparging resulting in higher air saturation and larger contact area between NAPL and gas during air sparging. Larger contacting interface between NAPL and gas means faster mass transfer of contaminants from NAPL to gas phase. This new technique, however, is limited to relatively volatile contaminants because vaporization is its basic mechanism of mass transfer. In this study, SEAS was tested at an elevated temperature for a semi-volatile n-decane, which is expected not to be a good candidate of SEAS application due to its low vapor pressure at ambient temperature. Three sparging experiments were conducted using 1-dimensional column (5 cm id, 80 cm length) packed with sand; (1) ambient temperature ($23^{\circ}C$), column saturated with distilled water, (2) SEAS at ambient temperature ($23^{\circ}C$), for n-decane contaminated sand, (3) SEAS at elevated temperature ($73^{\circ}C$), for n-decane contaminated sand. Higher air saturation was achieved by SEAS compared to that by air sparging without surfactant application. The n-decane removal efficiency of SEAS at elevated temperature was significantly higher(> 10 times) than that of ambient SEAS. The n-decane concentrations in the gas effluent from column during SEAS at $73^{\circ}C$ are found to be 10 times of those measured at ambient temperature. Thus, SEAS technique can be applied for removal of semi-volatile contaminants provided that an appropriate technique for elevating aquifer temperature is available.

• Journal of the Korean Institute of Navigation
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• v.22 no.2
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• pp.99-112
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• 1998

It is very important to investigate the hull response of a fishing vessel in waves to ensure the safe navigation and fishing operation in rough seas by preserving excellent seakeeping qualities. For this purpose, we measured pitching and rolling response of three fishing vessels in seas using real seas experimental measuring system and analyzed the data by statisticawl and spectral analyzing method. We compared the measured results with theoretical results to give the validity of measuring system and experimental results. From the result we know that a good agreement between the experimental and theoretical results are shown except following seas. But there are little difference between both results in the other deirection too, which are caused by the effects of short crested waves of real seas.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.4
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• pp.576-585
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• 2009

The aim of this study is to indicate that how to select the releasing fishes for the nourishment of fisheries resources in small ranching area around the Gunsan coastal seas. The collected data were analysed, and revealed that the proper fisheries for releasing around the seas are Limanda Yokohame, sebastes schlegeli, paralichthys olibaceus, black porgy and little clam.

• Journal of Wetlands Research
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• v.3 no.2
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• pp.107-118
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• 2001

The aim of this paper is to grasp eutrophication aspects in Namhae coastal seas, statistically analyzing existing data for their surface seawater and bottom mud. A pollution level(ignition loess) of bottom mud, on the whole, trended to increase as moving the coastal sea around Mokpo-Wando toward the east(Gyeongnam Namhae coastal seas). Especially, the pollution level(ignition loss=10.5%) of bottom mud for the coastal sea around Tongyeong-Keoje-Gosung was similar to that(10.3%) for the coastal sea around Masan-Jinhae, whose coastal marine pollution was the severest in Namhae coastal seas. It indicates that large amounts of pollutant from aqualculture facilities have been, thus far, accumulated on the coastal sea around Tongyeong-Keoje-Gosung, considering there was no significant inflow of sewage and industrial wastewater into this coastal sea. A COD, T-N, and T-P level of surface seawater, on the whole trended to increase as moving the coastal sea around Mokpo-Wando toward the east(Gyeongnam Namhae coastal seas). A COD level appeared to be the second grade of coastal water quality over the entire year throughout all Namhae coastal seas A T-N level exceeded the third grade of coastal water quality throughout all Namhae coastal seas except the coastal sea around Mokpo-Wando. Especially, a T-N level exceeded as many as three and six times over the third grade of coastal water quality in the coastal sea around Tongyeong-Keoje-Gosung and Masan-Jinhae, respectively. A T-P level appeared to be the second grade of coastal water quality in the coastal sea around Mokpo-Wando and the third grade of coastal water quality in the coastal sea around Yosu-Narnhae and Tongyeong-Keoje-Gosung, while it exceeded as many as two times over the third grade of coastal water quality. A degree of eutrophication of the surface seawater was 1.5 in the coastal sea around Mokpo-Wando and 11.9 In the coastal sea around Tongyeong-Keoje-Gosung, gradually increasing as moving toward the east(Gyeongnam Narnhae coastal seas). It sharply increased to 146.1 in the coastal sea around Masan-Jinhae. Because the degree of eutrophication throughout all Namhae coastal seas exceeded 1, a red tide organism could pose a possibility of proliferation at any place of Namhae coastal seas if other requirements were satisfied. It indicates that a red tide may move to another place once a red tide breaks out at a place of Namhae coastal seas.

• Journal of KIISE
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• v.42 no.7
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• pp.846-851
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• 2015

Seas and swells are basic wave types in ocean surface simulation and are very important elements in the simulation of ocean background. In this paper, we propose a real-time simulation method, for reproducing realistic seas and swells, to be used in real-time simulators such as ship maneuvering simulators. Seas and swells have different visual properties. Swells have relatively longer wavelengths and round crests compared with seas, therefore they are visualized globally with large meshes and procedural methods. Parameters to illustrate swells are extracted from ocean wave spectra. Conversely, seas have shorter wavelengths and their characteristics are only clearly apparent near to the observation point. Here, we present visualization of seas based on a statistical wave model using ocean wave spectra, which provides realistic results in a reactively small area.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.121-134
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• 2019

The areas be affected maritime police authority of the Republic of Korea, are largely classified as inland waters, territorial waters, exclusive economic zone and continental shelf(hereinafter referred to as "domestic sea area") and high seas. Of these, the maritime police authority in domestic sea area follows a municipal law that accommodates the United Nations Convention on the Law of the Sea(UNCLOS). In addition, this Convention shall apply on the high seas. Meanwhile, on the high seas, foreign vessels other than domestic vessels are allowed to be subject to limited jurisdiction only for the anti-mankind criminal acts, such as piracy etc. this is in accordance with the principle of "Freedom of the high seas" and "maritime flag state," under this Convention. However, the illegal acts of foreign vessels that threaten the security of coastal states and the safety of ships on the high seas can cause many types of crimes other than anti-mankind criminal acts, and the jurisdiction of the coastal states exercised may lead to conflicts between countries. Therefore, this article would like to suggest a plan for institutional improvement to maintain international maritime order on the high seas and secure maritime police authority in coastal states.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.121-122
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• 2006

The legal regime of the high seas has traditionally been characterised by the dominance of the principles of free use and the exclusivity of flag State jurisdiction. It means that the high seas are open to all States, and no State may validly purport to subject any part of them to its sovereignty. but it has not always been so. accordingly, here we discuss the general regime of the high seas in this papaer.

• Korean Journal of Remote Sensing
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• v.17 no.4
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• pp.345-357
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• 2001

This review provides a summary of data assimilation applied to the seas around Korea. Currently the worldwide efforts are devoted to applying advanced assimilation to realistic cases, thanks to improvements in mathematical foundations of assimilation methods and the computing capabilities, and also to the availability of extensive observational data such as from satellites. Over the seas around Korea, however, the latest developments in the advanced assimilation methods have yet to be applied. Thus it would be timely to review the progress in data assimilation over the seas. Firstly, the definition and necessity of data assimilation are described, continued by a brief summary of major assimilation methods. Then a review of past research on the ocean data assimilation in the regional seas around Korea is given and future trends are considered. Special consideration is given to the assimilation of remotely-sensed data.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.1 s.151
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• pp.1-7
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• 2007

Recently, researches to find rational mathematical model for prediction of capsizing have been progressed by ITTC. Lee(1997) developed a mathematical model which describes 6 DOF transient motions, such as capsizing, of a ship in regular waves. In this study a mathematical model for prediction of capsizing in following and quartering seas is developed based on Lee's model. And factors affecting prediction of capsizing are analyzed through comparing simulation results with experimental results. Present simulation results are compared with ITTC bench mark test results. In rolling tests with beam seas and tree runs with stern quartering seas, capsizing events are predicted well. But calculated roll angle is larger than experimental one. It is found that nonlinear manoeuvring coefficients don't affect the prediction of capsizing events.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.13
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• pp.411-437
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• 2000

It is unsafe to attempt a complete definition of the expression 'perils of the seas', because in practice the question 'what is a peril of the seas' is inextricably woven up with the further question, 'was the loss proximately caused by the sea peril ?' Such casualties as stranding, collision and heavy weather appear with monotonous regularity in the daily reports, and are the obvious examples. However, what can be included in the term 'perils of the seas' seems to be inexhaustible, although most circumstances appear to have been covered by the Courts. Two cases heard in 1887 were instrumental in defining perils of the seas. In The Xantho Lord Herschell made the following remarks: "The term ... does not cover every accidents or casualty which may happen to the subject matter of insurance on the sea. It must be a peril 'of' the sea. Not every loss or damage of which the sea is the immediate cause is covered by these words. They do not protect, for example, against that natural and inevitable action of the winds and waves which results in what may be described as wear and tear. There must be some casualty, something which could not be foreseen as one of the necessary incidents of the adventure. The purpose of the policy is to secure an indemnity against accidents which may happen, not against events which must happen. ... If a vessel strikes upon a sunken rock in fair weather and sinks, this is a loss by perils of the sea."