• Journal of the Society of Naval Architects of Korea
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• v.37 no.1
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• pp.50-59
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• 2000

This paper presents a brief outline of dynamic stability of a damaged ship at final stage of flooding in rough beam wind and waves. One degree-of-freedom, roll equation is adopted with effects of flooding water and external forces due to wind and waves, but without effect of sloshing. We discuss the dynamic stability of the damaged ship in terms of capsizing probability based on risk analysis, the method of which was firstly proposed by Umeda et al.[6] to high speed craft in intact condition. As a result, we can evaluate the dynamic stability of the damaged ship in probabilistic manner according to sea state, operating condition and damage situation.

• KCID journal
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• v.17 no.2
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• pp.105-114
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• 2010

Tidal land reclamation provided water resources and land for agriculture and contributed stable crop production. However, climate change by global warming disrupts the hydrologic circulatory system of the earth resulting in sea level rise and more frequent flood for reclaimed arable land. Recently, Suyu reclaimed paddy field in Jindo-gun experienced prolonged inundation after heavy rainfall and there is a growing risk of flood damage. Onsite survey and flood analysis using GATE_Pro model of Korea Rural Corporation were conducted to investigate causes of flooding. To perform the analysis, input data such as inflow hydrograph, the lowest elevation of paddy field, neap tide level, management level of Gunnae estuary lake at the time of the flood were collected. Flood analysis confirmed that current drainage facilities are not enough to prevent 20year return period flood. The result of analysis showed flooding more than 24hours. Therefore, flood mitigation alternatives such as sluice gate expansion, installation drainage pumping station, refill paddy land, and catch canal were studied. Replacing drainage culvert of Suyu dike to sluice gate and installing drainage pumping station at the Gunne lake were identified as an effective flood control measures. Furthermore, TM/TC (SCADA) system and expert for gate management are required for the better management of drainage for estuary dam and flood mitigation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.2
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• pp.99-106
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• 1993

A two-dimensional numerical analysis is performed for the simulation of intertidal-flat and analysis of hydraulic characteristics during seadike construction in Sae-Man-Keum tidal basin. The shallow water equations are selected as a mathematical model and the Leendertse's ADI scheme is used as the corresponding numerical model. The simulated results of tide and current by the present model agree welt with the experimenta1 results by the hydraulic Lab. or ADC (1989). In the application of the model, the possibility of rapidly varied flow analysis and the introduction of turbulence model required for more accurate hydraulic calculation at closing gap are described. The successive simulation of flooding/drying effects by a modification of the method by Stelling et al. (1986) can easily be used for the intertidal-flat analysis during tidal reclamation.

• International Journal of Computer Science & Network Security
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• v.21 no.5
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• pp.23-30
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• 2021

In recent years, hazardous flash flooding has caused deaths and damage to infrastructure in Saudi Arabia. In this paper, our aim is to assess patterns and trends in climate means and extremes affecting flash flood hazards and water resources in Saudi Arabia for the purpose to improve risk assessment for forecast capacity. We would like to examine temperature, precipitation climatology and trend magnitudes at surface stations in Saudi Arabia. Based on the assessment climate patterns maps and trends are accurately used to identify synoptic situations and tele-connections associated with flash flood risk. We also study local and regional changes in hydro-meteorological extremes over recent decades through new applications of statistical methods to weather station data and remote sensing based precipitation products; and develop remote sensing based high-resolution precipitation products that can aid to develop flash flood guidance system for the flood-prone areas. A dataset of extreme events has been developed using the multi-decadal station data, the statistical analysis has been performed to identify tele-connection indices, pressure and sea surface temperature patterns most predictive to heavy rainfall. It has been combined with time trends in extreme value occurrence to improve the potential for predicting and rapidly detecting storms. A methodology and algorithms has been developed for providing a well-calibrated precipitation product that can be used in the early warning systems for elevated risk of floods.

• Journal of the Korean Society of Marine Environment & Safety
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• v.2 no.1
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• pp.57-65
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• 1996

The latest date, No. 1 YouII was grounded and sunk into the sea at MAMHYUNGJEDO ( South brother Island) in Sep. 21. 1995, and M.V. Sea Prince of V.L.C.C also made a big oil poullution accident owing to Typhoon "Paei" at front sea of Yeu Choun on Jul. 25. 1995. The large or small scall scale of oil poullution accident frequently was occurred about 300-350 cases per ine(1) year. The countries advanced in marine relations like as, nited Kingdom and Japan, have perfect system The country of expert education, training and oil recovery equipments in oil poullution accidents. The large quantity oil skimming ship's basic condition need general skimming ship which was high speed and large quantity skimming ability , and hve to store the recovered oil into tanks This oil skimming shop are composit the skimmer whuch move up and down according to the wace movements, storage tank which storage the recovered oil in after side, transfer pump which transformed from flooding tank to separating tank and separating tank which separated the oil mixtures, Also there are cylindrical floated which keep the auto positing, gate which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. Also there are cylindrical floated which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. The important arrangement is twin arm which moved by two hinge and move te skimming unit by wave movement. In gate of inside, made long wear in the gate bellow position, there are also connected the flexible hose for oil mixtures drop. The separating tank composited with multi-divided bulkhead for ffective oil and sea water separating by settling and flotation principle. As use the above natural princile and equipment, we can remove the large quantity oil by developed oil skimming ship.ming ship.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.201-211
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• 2022

At the center of the Noryang waterway, the Gwangyang bay area (including the Yeosu Strait) is located at the west, and the Jinju bay area (including Gangjin bay and Sacheon bay) is located at the east. Freshwater from several rivers is flowing into the study area. In particula,r the event of flood, great quantities freshwater flow from Seomjingang (Seomjin river) into the Gwangyang bay area and from Gahwacheon (discharge from Namgang Dam) into the Jinju bay. The Gwangyang and Jinju bay are connected to the Noryang waterway. In addition, freshwater from Seomjingang and Gahwacheon also affect through the Noryang waterway. In this study, we elucidated the characteristics of the tidal exchange rate and residence time for dry season and flood season on 50 frequency, considering freshwater from 51 rivers, including Seomjingang and Gahwacheon, using a particle tracking method. We conducted additional experiments to determine the effect of freshwater from Seomjingang and Gahwacheon during flooding. In both the dry season and flood season, the result showed that the particles released from the Gwangyang bay moved to the Jinju bay through the Noryang waterway. However, comparatively small amount of particles moved from the Jinju bay to the Gwangyang bay. Each experimental case, the sea exchange rate was 44.40~67.21% in the Gwangyang bay and 50.37~73.10% in the Jinju bay, and the average residence time was 7.07~15.36days in the Gwangyang bay and 6.45~12.75days in the Jinju bay. Consequently the sea exchange rate increased and the residence time decreased during flooding. A calculation of cross-section water flux over 30 days for 7 internal and 5 external areas, indicated that the main essential flow direction of the water flux was the river outflow water from Seomjingang flow through the Yeosu strait to the outer sea and from Gahwacheon flow through Sacheon bay, Jinju bay and the Daebang waterway to the outer sea.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.249-256
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• 2011

Causing by green house gas emission, global warming is being accelerated significantly. This global warming cause world climate to change quiet different than before and we call this phenomenon is Climate Change. Environmental Impact Assessment being implemented in Korea is to prevent predicted environmental impacts from deteriorating within the domestic information and situation. As the climate change is getting severe, new meteorological records can be occurred which is exceeded existing statistical data. According to KMA(Korea Meteorological Administration) data, maximum value of precipitation and temperature in many regions changed with new data within last decade. And these events accompanied with landslides and flooding, and these also affected on water quality in rivers and lakes. According to impacts by climate change, disasters and accidents from heavy rain are the most apprehensive parts. And water pollution caused by overflowed non-point sources during heavy rain fall, fugitive dust caused by long-term drought, and sea level rise and Tsunami may affect on seaside industrial complex should be worth consideration. In this review, necessity of mutual consideration with influences of climate change was considered adding on existing guideline.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.340-348
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• 1997

Sledge net samples were taken over the neap and spring tide cycles in January 1993 from the bottom and surface of 1 m depth and at the water's edge in the sandy shore surf zone of Dolsando, southern Korea. Zonation pattern of three dominant gammarid amphipods was compared. The amphipods were more abundant on the bottom and at water's edge than in the surface. Average densities at both sites of Pontogeneia rostrata and Allorchestes angusta were higher during the neap tide than the spring tide, whereas that of Synchelidium lenorostralum was lower during the neap tide. P. rostrata migrated horizontally during the flooding and ebbing tides, but S. lenorostralum and A. angusta did not. Unlike other species, P. rostrata was significantly more abundant at night, suggesting its active nocturnal movement. During flooding tide, P. rostrata was not found on the shore above the mean sea level (MSL) during daytime, but found in 100 cm above MSL at night. Zonal distribution of P. rostrata which was restricted from MSL to 250 cm below MSL, however, did not vary with the day-night cycle during ebbing tide. S. lenorostralum and A. angusta were not found during flooding tide but ebbing tide. The upper distribution limit of the former was 150 cm below MSL, and the distribution of the latter ranged from MSL to 150 cm below MSL. The highest densities of P. rostrata, S. lenorostralum and A. angusta were 32, 26 and 3 ind. $m^{-2}$, respectively. We discussed the relationships between the distribution pattern of three dominant species of gammarid amphipods and their life styles in the sandy shore.

• Journal of the Korean association of regional geographers
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• v.9 no.2
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• pp.203-216
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• 2003

The process of constructing coastal digital elevation model(DEM), for the 3 dimensional analysis, is composed by abstracting land layers for land elevation and water depth, reprojecting UTM, relocating geographical grid, and interpolating works. The geomorphic set of shallow sea, including tidal current, tidal zone deposition, and water depth distribution, was analyzed by eye search of Landsat TM image, masking of land zone, band combination and regression analysis. Some horizontal differences, between combined DEM and surveyed data of shallow sea, was corrected for analysis. Analyzed geomorphic elements are stream channel, alluvial fan, coastal terrace, tidal current. and shallow sea bank. Results of analysis present that transported fluvial materials influence tidal sedimentation, especially from Gahwacheon river, for the role of artificial draining flooding waters from Jinyang Reservoir, almost in the summer season. In the coastal area with less tidal current, more fine materials are deposited. The influence of currental deposition are higher on small pockets with west coast of well developed terraces. The lower skirt of alluvial fans developed into the tidal zone of shallow sea. Small pocket type bays are closed by coastal current, and less influenced from tidal deposition. The bank of Jinju Bay are developed originally from submerging of remnant erosional mountain ranges, and play on the role of trapping fine materials.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.295-300
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• 2010

Recently, many tsunamis triggered by impulsive undersea ground motions occurred in subduction zones around the Pacific Ocean area including the East Sea surrounded by Korea, Japan and Russia. The wave height of a tsunami may be in the order of several meters, while the wavelength can be up to 1,000 km in the ocean, where the average water depth is about 4 km. A tsunami could cause a severe coastal flooding and property damage not only at neighboring countries but also at distant countries. A fundamental and economic way to mitigate unusual tsunami attacks is to construct tsunami hazard maps along coastal areas vulnerable to tsunami flooding. These maps should be developed based on the historical tsunami events and projected scenarios. The map could be used to make evacuation plans in the event of a real tsunami assault.