• Water for future
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• v.15 no.1
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• pp.57-62
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• 1982

In order to make a numerical modeling for the one dimensional unsteady flow which expressed by Saint Venant partial differential equations, Preissman's implicit schem was used, and it's stability and accuracy was investigated. By introducing recurrence relations make it possible to use double sweep algorithm. Effective parameters to the result were the values of the C$$ and the Chezy coefticient. In order to get numerical solutions whith enough accuracy, C$$ should not be far from the value of1, and when the criteria of the $\theta$ was 0.6<$\theta$<1.0, the rewult was always stable for any condition. This model should be calibrated by real field data, and expected to be developed for the simulation of the river system and to the long wave analysis for one dimensional coastal zone problem.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.257-262
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• 2002

Numerical model introduced in this study combines wave refraction-diffraction, breaking, bottom friction, lateral mixing, and critical shear stress and three sub-models for simulating waves, currents, and bottom change were briefly discussed. Simulations of beach processes and harbor sedimentation were also described at the coast neighboring Bangpo Harbor, Anmyundo, Chungnam, where the area has suffered from accumulation of drifting sand in a small fishing harbor with a wide tidal range. We also made model test for the case of a narrow tidal range at Nakdong river's estuary area to understand the effect of water level variation on the littoral drift. Simulations are conducted in terms of incident wave direction and tidal level. Characteristics of wave transformation, nearshore current, sediment transport, and bottom change are shown and analyzed. We found from the simulation that the tidal level impact to the sediment transport is very important and we should apply the numerical model with different water level to analyze sediment transport mechanism correctly. Although the model study gave reasonable description of beach processes and harbor sedimentation mechanism, it is necessary to collect lots of field observation data, including waves, tides and bottom materials, etc. for better prediction.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.68-69
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• 2014

At the present, ship traffic monitoring and management are focused on the harbor area and the specified coastal zone in South Korea. It, however, is required that the Jurisdictional Sea Area of South Korea is monitored from two viewpoints: Safety and Security. Through a safe sea line (transport route) over the world, it is possible to expand our ocean economical territory. As a first step, we have been in field campaigns for integrated ship monitoring on the Ieodo Ocean Research Station in November 2013 after the first test in Gyunggi Bay.

• Ocean and Polar Research
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• v.22 no.2
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• pp.81-90
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• 2000

Supposed construction of a large port in the mouth of Tuman River requires careful examination of possible unfavorable ecological consequences for the Far Eastern Federal Marine Reserve. Since the Tuman River is the largest source of suspended material and possible contaminants flowing into the sea, and in order to understand how this material is allocated in the coastal zone, analyses are needed to check possible pathways of water transport and circulation system in the region. Linearized shallow water equations were used for numerical simulation of the wind-driven circulation to the north off the Tuman River mouth. The model results satisfactorily agreed with in situ data. The model circulation patterns are largely dependent on the wind direction and are conformed by the distribution of bottom sediments, and by the location of organic carbon and some pollutants accumulation zones. The most unfavorable situation for the Marine Reserve is the case of the southwesterly wind; even with quite moderate wind, the waters polluted by the run-off from the Tuman River can attain the south section of the Marine Reserve during the diurnal period.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.200.1-200.1
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• 2011

Underground air is a special energy source in Jeju and distributes lava cave, pyroclastic, open joint, and crushing zone. A possible area to utilize underground air is 85% of Jeju except to the nearby area of Sambang Mt. and 25m high coastal area from sea level. In Jeju, underground air is used for heating agricultural facilities such as greenhouse cultivated mangos, Hallbong and mandarin orange, pigsty, mushroom cultivation house, etc. and fertilizing natural $CO_2$ gas by suppling directly into agricultural facilities. But this heating method causes several problem because the underground air has over 90% relative humidity and is inadequate in heating for crops. Mangos are the most widely grown tropical fruit trees and have been cultivated since 1993 in Jeju. In Jeju, the cultivating area is about 20ha and amount of harvest is 275ton/year in 2010. In this study, the heat pump system using underground air as heat source was installed in mangos greenhouse which area is $495m^2$. The capacity of heat pump system and heat storage tank was 10RT, 5ton respectively and heating effect and heating performance of the system were analysed.

• ALGAE
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• v.27 no.4
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• pp.249-258
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• 2012

Nongeniculate coralline red algae are a common element of the Brazilian coastal zone, especially associated to coral reefs. During the course of ecological studies at Parque Municipal Marinho do Recife de Fora, two species of non-geniculate Corallinales were the major organisms covering the reef. Analyses of the vegetative and reproductive features of the species were analyzed; indicating that one new species of the genus Lithothamnion is proposed here based on the combination of several features associated with anatomy of the tetrasporangial conceptacles in relation to other species of the genus for which modern accounts are available. This new proposal along with other new species, new combinations and range extension of some species of the genus based in similar features clearly suggest that stability in species delimitation is possible. The second species found Pneophyllum conicum represents a range extension of more than 6,000 km from the Pacific in to the Atlantic Ocean suggesting that some nongeniculate species are widely distributed. The occurrence and abundance of these species supports and emphasizes the need for an extensive taxonomic reassessment of coralline red algae in the context of Brazilian coral reef biodiversity.

• Ocean and Polar Research
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• v.24 no.4
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• pp.501-524
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• 2002

Article 121 of the UNCLOS stipulates the regime of islands and grants different jurisdictions to islands and rocks. Especially, paragraph 3 gives different definitions and distinguishes the legal status of between islands and rocks. That is, rocks, which cannot sustain human habitation or economic life cannot have their own EEZ, continental shelf or the great-sphere maritime jurisdiction. In this paper various theories and state practicess on islands and rocks are examined with reference to Article 121 of UNCLOS. Also, the status of Dokdo as a rock or an island is examined in accordance with the interpretation of Article 121 of UNCLOS. National legislations, practices, and many scientific opinions are often contradictory and controversial with respect to the interpretation of Article 121 of the UNCLOS. However, it is believed that Article 121 of UNCLOS, particularly paragraph 3 has to be interpreted more strictly. That is because the highly developed modem scientific technology can be meaningless when the criteria of Article 121 of UNCLOS are to be inappropriately applied. Insular figures like ${\ulcorner}rocks{\lrcorner}$ could bring the inequitable effects disadvantageous toward the other party when the maritime delimitation is applied. Claiming and Intentionally extending maritime zone of a coastal states by assigning EEZ for small insular figures like ${\ulcorner}rocks{\lrcorner}$ is over-zealous nationalism which is illegal, and such practices must be recognized as actions bringing great harm to the neighboring nations and demise of the sprit of all mankind.

• Ocean and Polar Research
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• v.24 no.1
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• pp.55-61
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• 2002

Eelgrass, Zostera marina L. widely spreads throughout all the coastal areas of the Korean Peninsula. However, some previously reported eelgrass populations disappeared. The disappearance was probably caused by anthropogenic disturbance such as reclamation and pollutant or exceeded nutrient release. Eelgrass beds occurred from the intertidal to the subtidal zone, mainly in lagoon, estuaries, ports, barrier reef and bays. Eelgrass beds were also found at the intertidal mud and sand flats, subtidal mud and sandbank in more exposed areas. Habitat characteristics of eelgrass beds distributed on the coasts of the Korean Peninsula varied among coast areas. Eelgrass distributed constantly throughout the southern coast of Korea, while the distribution was limited at lagoon, bay, port, or barrier reef on the eastern coast, because of steep water depth and high wave energy in that coast. On the western coast, eelgrass mainly appeared at the intertidal and subtidal zones in islands. Sediment characteristics of the Z. marina beds varied with locality, tidal current and water motion. Sediments of Z. marina beds were composed of sand, muddy sand, sandy mud and mud. Mean grain size ranged from 1.5 to 4.1 phi.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.13-14
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• 2003

It is generally well known that Quaternary is characteristic geologically in terms of glacial and interglacial repeats and their associated unconformity formation. This paper deals with the first finding of the characteristic and significant meaningful unconformity between Holocene and late Pleistocene, which implies submergence and emergence of the tidal sedimentary basin along the western coastal zone of Korea during interglacial stage(IOS-5e) and glacial time(IOS-2). The stratigraphy of intertidal deposits in the Haenam Bay, western coast of Korea shows two depositional sequence units (Unit I of Holocene and Unit II of late Pleistocene) bounded by an erosional surface of disconformity. The disconformity is related to the latest Pleistocene sea-level lowstands (probably during the LGM). The Unit II is interpreted as intertidal deposit showing tidal sedimentary structures and crab burrow ichnology and has two parts (the upper part and the lower part) showing different lithology and character. The upper part of Unit II shows characteristic subaerial exposure features (emergence) and its related lithology. Such subaerially exposed upper part (more or less 4m to 5m in thickness) is characterized by yellow-brownish sediment color, cryoturbat-ed structure, crab burrow ichnofacies and high value of shear strength. Geochemical and clay mineral analyses of the upper part sediments also indicate subaerial exposure and weathering. In particular, very high value of magnetic susceptibility of the upper part in comparison to that of the lower part is interpreted as pedogenetic weathering during the subaerial exposure period.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.481-484
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• 2009

It has been reported that reckless marine structures located in the coastal zone deteriorate environment and tourism due to industrialization and tourist development. Therefore, it needs to analyze am appropriate remodeling plan for environment, tourism, and safety in current marine structures and then establish the standard for the optimum remodeling design and the guidance for maintenance. Furthermore, it needs a precise simulation program about typhoons and tidal waves for the environment, safety and a three-dimensional positioning and structural modeling currently built in structures. This research has a purpose of suggesting a theoretical method for the establishment of GIS information.