• Journal of Wetlands Research
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• v.18 no.1
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• pp.16-23
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• 2016

The purpose of this study is to analyze quantitatively the inundation causes by applying the prevention of performance objectives using the urban storm water runoff model XP-SWMM. The model was built by using DTM and storm sewer-network with the storm sewer and geo-data of the study area as input-data to assess the current performance of prevention. An analysis of the causes of the inundation by the frequency and the rainfall-duration. As a result, lack of pipe capacity due to flooding, as well as inundation heavier that the backwater rainfall occurs due to the rise of water level of outside. For solve the inundation damage, It is necessary to improvement pipe of capacity lack and installation of a flood control channel.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.4
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• pp.295-302
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• 2007

Abnormally high waves occurring at the east coast of korea were observed at five field measurement stations and their characteristics were analyzed with the use of wind data provided by the Korean Meteorological Administration. The high waves occurred because strong Donghae twister that was developed by extratropical cyclone blew while high swell arrived at the east coast of Korea. At Sokcho, the most northern site among the five measurement stations, maximum gust speed was 63.7 m/s and significant wave height reached at its maximum of 9.69 m with the corresponding peak wave period of 12.8 s. The reason for appearance of the abnormally high waves is that high swell continued while the twister blew strongly. Moreover, the wind direction was the same as the direction of swell propagation, which maximizes the increase of wave height due to superposition of swell and wind-generated waves. On the east coast of Korea, outbreak of this type of storm waves is very probable in winter season so that it is requested to establish a countermeasure of minimizing possible damage caused by the storm waves.

• Journal of Korea Water Resources Association
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• v.39 no.11 s.172
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• pp.969-976
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• 2006

The purpose of this study is to trace the flood inundation area around rural small stream by using RADARSAT image because it has the ability of acquiring data during storm period irrespective of rain and cloud. For the storm August 9, 1998 in the Anseong-cheon watershed, three RADARSAT images before, just after and after the storm were used. After ortho-rectification using 5 m DEM, two methods of RGB composition and ratio were tried and found the inundated area in the tributary stream, the Seonghwan-cheon and the Hakjeong-cheon. The inundated area had occurred at the joint area of two streams, thus the floodwater overflowed bounding discharge capacity of the stream. The progression of damage areas were stopped by the local road and farm road along the paddy. The result can be used to acquire the flood inundation data scattered as a small scale in rural area.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.5
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• pp.41-52
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• 2004

In this study, parameters of long and short term runoff model were optimized using genetic algorithm as a basic research for integrated water management in a watershed. In case of Korea where drought and flood occurr frequently, the integrated water management is necessary to minimize possible damage of drought and flood. Modified TANK model was optimized as a long term runoff model and storage-function model was optimized as a short term runoff model. Besides distinguished parameters were applied to modified TANK model for supplementing defect that the model estimates less runoff in the storm period. As a result of application, simulated long and short term runoff results showed 7% and 5% improvement compared with before optimized on the average. In case of modified TANK model using distinguished parameters, the simulated runoff after optimized showed more interrelationship than before optimized. Therefore, modified TANK model can be applied for the long term water balance as an integrated water management in a watershed. In case of storage-function model, simulated runoff in the storm period showed high interrelationship with observed one. These optimized models can be applied for the runoff analysis of watershed.

• Journal of Advanced Research in Ocean Engineering
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• v.1 no.1
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• pp.1-13
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• 2015

Post-Katrina investigations revealed that most earthen levee damage occurred on the levee crest and landward-side slope as a result of either wave overtopping, storm surge overflow, or a combination of both. In this paper, combined wave overtopping and storm surge overflow of a levee embankment strengthened with high performance turf reinforcement mat (HPTRM) system was studied in a purely Lagrangian and meshless approach, two-dimensional smoothed particle hydrodynamics (SPH) model. After the SPH model is calibrated with full-scale overtopping test results, the overtopping discharge, flow thickness, flow velocity, average overtopping velocity, shear stress, and soil erosion rate are calculated. New equations are developed for average overtopping discharge. The shear stresses on landward-side slope are calculated and the characteristics of soil loss are given. Equations are also provided to estimate soil loss rate. The range of the application of these equations is discussed.

• Water for future
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• v.28 no.6
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• pp.203-215
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• 1995

Operation models for storm water pumps in detention pond were developed in order to reduce the damage by inundation in urbanized area. The return periods (10, 20, 30 years) of rainfall were selected to estimate inflow discharge to detention ponds. Inflow hydrographs of detention ponds were derived by using the SWMM, and Petri net diagrams were selected to analyze the pump actions. Safety and efficiency of pumps and detention ponds were estimated by penalty index. In order to verify the models, the models were applied to three selected detention ponds in Seoul area. In numerical experimental results, the developed model 3 is more effective in inland flooding prevention than the existing one, and may be used to design and evaluate detention ponds with real time data of rainfall.

• Ocean Systems Engineering
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• v.4 no.3
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• pp.215-241
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• 2014

Steel catenary riser (SCR) is a popular/economical solution for the oil/gas production in deep and ultra-deep water. The behavioral characteristics of SCR have a high correlation with the motion of floating production facility at its survival and operational environments. When large motions of surface floaters occur, such as FPSO in 100-yr storm case, they can cause unacceptable negative tension on SCR near TDZ (touch down zone) and the corresponding elastic deflection can be large due to local dynamic buckling. The generation, propagation, and decay of the elastic wave are also affected by SCR and seabed soil interaction effects. The temporary local dynamic buckling vanishes with the recovery of tension on SCR with the upheaval motion of surface floater. Unlike larger-scale, an-order-of-magnitude longer period global buckling driven by heat and pressure variations in subsea pipelines, the sub-critical local dynamic buckling of SCR is motion-driven and short cycled, which, however, can lead to permanent structural damage when the resulting stress is greatly amplified beyond the elastic limit. The phenomenon is extensively investigated in this paper by using the vessel-mooring-riser coupled dynamic analysis program. It is found that the moment of large downward heave motion at the farthest-horizontal-offset position is the most dangerous for the local dynamic buckling.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.126-126
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• 2021

Stormwater reduction plays an important role in the safety and resilience to flooding in urban areas. Due to rapid climate change, the world is experiencing abnormal climate phenomena, and sudden floods and concentrated torrential rains are frequently occurring in urban basins and the amount of outflow due to stormwater increases. In addition, the damage caused by urban flooding and inundation due to extreme rainfall exceeding the events that occurred in the past increases. To solve this problem, water supply, drainage, and water supply for sustainable urban development, the water management paradigm is shifting from sewage maintenance to water circulation and water-sensitive cities. So, in this study, The purpose of this study is to examine measures to increase the resilience of urban ecosystem systems for urban excellence reduction by analyzing the effects of green infra structures and LID techniques and evaluating changes in resilience. In this study, for simulating and analysis of runoff for various stormwater patterns and LID applications, Storm Water Management Model (SWMM) was used.

• Journal of Korean Society of Disaster and Security
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• v.7 no.1
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• pp.17-25
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• 2014

Due to the recent climate change impact, natural disasters occur due to sea surface rising, typhoon attacks, flash floods, local heavy rainfalls, landslides, and coastal area erosion, continuing to cause human and property damage. These impacts, coupled with urbanization and industrialization activities, are turning the previously safe areas into disaster-vulnerable areas, increasing human and economic damage. This paper aimed to prepare measures designed to minimize human damage in natural disaster vulnerable parts of South Korea in summer. Toward that end, how vulnerable areas were managed and what the damage was like were studied. Also, cases of human damage and statistics there of were reviewed and analyzed, relevant problems were derived, and thus structural and non-structural measures designed to minimize human damage were presented.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.389-393
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• 2010

The Objective of this study was to develop a system for visualizing inundation area by using 1-D numerical model analyzing damage information such as inundation area, facilities, land usages, population, building, loads. In this study, we have reviewed hydraulic models to select a flood model for simulation of discharges, water depths and velocities. The study area is Namhan River from Youngwol to Paldang Dam which had a flood damage on upper and below regions of Chungju Dam by a storm event in 2006. At the first, we developed the DB system base on GIS thematic map, ortho images, cadastral maps to analyze flood damages and support decisions making. Changing the boundary conditions such as discharge at the gauging stations, flood simulations were performed and then damages were extracted from the databases information support system based on 1-D numerical hydraulic model, it is expected to be able to analyze flood damages and support a decision making for reduce flood relate damages. In the future, the system developed in this study could be applied for flood forecasting system of small scaled streams.