• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.4
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• pp.211-222
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• 2020

This study suggested a method calculating the influence of effluent discharge from Saemangeum sluice-gates using the particle tracking model. For 2017, we presented the seasonal effects of effluent discharge as probability spatial distributions and compared with the results of the water age, one of the indicators of transport time scale. The influence of sluice-gates effluent discharge increases radially around Sinshi or Gaseok gates, which are expected to be biased toward the south in winter and north in summer due to the effect of seasonal winds. Although the results of the prediction are limited to the 2017 situation, the method of calculating the influence of sluice-gates effluent discharge using the Lagrangian particle tracking model can be used to predict the future of the around Saemangeum.

• Journal of Korea Port Economic Association
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• v.28 no.3
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• pp.215-234
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• 2012

Since ports play a role of gateway to the sea and hinterlands, it is essential to analyse the networks of shipping and inland when evaluating the function and development of a port. The container port of Gwangyang, starting to operate its facilities in 1998, has developed itself as a hub port. Using the data of shipping schedules of Korean ports and the measurement of centrality in sociology, this study analyses the process of world-wide shipping network expansion in Gwangyang and concludes some implications including earlier development of shipping networks due to incentives to shipping companies. Although Gwangyang port also has been expanding its inland network through developing trucking, railway transport, and coastal shipping, it has weakness in inland network as in the cases of interruption in 2004, resumption in 2009 and re-interruption in 2012 at coastal shipping. In 2000s the expansion of shipping and inland networks at the newly built container ports such as Pyungtaek, Ulsan, and Gunsan has enticed the competition among Korean ports at each hinterland. Nevertheless, the operation of Gwangyang container port is considered to affect indirectly the relocation of some manufacturers including Samsung Electronics. Studies on interrelation between development of container port and geographical demography of manufacturers are needed to assess the effects of container port on regional economy.

• Journal of Korea Water Resources Association
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• v.47 no.11
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• pp.1027-1037
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• 2014

Flow and bed changes due to tributary inflow variation at the confluence of the Namhan River and the Geumdang Stream were analyzed in this study using a two-dimensional numerical model. As a result of the numerical analysis, the velocity downstream of the confluence was greater than the velocity upstream of the confluence in the main channel regardless of the magnitude of tributary inflow. However, as tributary discharge increased, the channel erosion was accelerated and the dry area was produced at the tributary. Due to the bed erosion at the tributary, sediment transport was increased and the eroded sediments were deposited in the confluence area. The deposition in the confluence area changed the flow direction at the main channel to the left side and the localized flow eroded the channel bed at the left side. Therefore, it is expected that bank failure due to continuous bed degradation is possible in this area.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.1
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• pp.101-109
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• 2008

Several numerical models for predicting beach profile changes have been developed by many researchers. Many of the earlier models are known to simulate the erosional profiles with the formation of offshore bar. However, most of the models don't have proper mechanism to incorporate the recovery process of the eroded profiles after a storm and can not simulate the beach accretion with acceptable accuracy. In order to overcome these shortcomings, we propose a new numerical model which has new features to simulate the accretional phase of beach recovery process after storm including such as redistribution of suspended sand particles near the breaking point. The simulation results of the proposed model were compared with LWT (Large Wave Tank) experiments performed at CRIEPI (Central Research Institute of Electric Power Industry in Japan) and CE (the Us Army Corps of Engineers) and it was shown to have performed better compared to SBEACH (Storm-induced BEAch CHange).

• Journal of Navigation and Port Research
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• v.36 no.8
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• pp.659-664
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• 2012

Coastal vegetaion consists of rooted flowering marine plants that provide a variety of ecosystem services to the coastal areas they colonize. The attenuation of waves and sediments stabilization are often listed among these services. From this point of view, artificial vegetation model is an effective method of controlling sea bed and stabilization without damaging the landscape or the stability of the coastaline. In this study, numerical and hydraulic physical test for predicting deposition proces of a navigation channel caused by wave action is proposed. In the numerical model, we develop a numerical model for describing the wave attenuation and sediment transport in a navigation channel with a vegetation area. In addition, hydraulic model tests is performed in a navigation channel with irregular waves to examine the effect of vegetation in relation to deposition reduction in navigation channel. A comparison between the results of hydraulic and numerical tests shows resonable agreement.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.273-273
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• 2002

Masan barber was situated in S.Korean southern central coast. And it is contributing greatly in S.korea's economy development to international trading port of Heaven's blessing that possess natural, geographical situation. Also, because there are Masan free tax area and chanwon heavy industrial complex, sachon air industrial complex etc. on back, it is important permanency in our country. Specially, because inland transport routes such as southern highway, Guma highway and national road system are developed well, the importance is very high. Masan harbor 1899.05.01 be that opened, the 1st and 2nd (central pier) was build 1938∼1944 year, and the 3rd pier was 1973∼1978 year. the 4th pier was 1974∼1983 year, 5th pier was 1984∼1988, 6th pier (west pier) was 1985∼1992 year. it was developed over 100 years. But, it did great many harbor and bay development of last 100 yens but research about coastline change and seashore reclamation is insufficient. Therefore, this research executed research about coastline change of Masan bay of last 100 years, In this study, we analyzed aerial photographs and tide data for the past 100 years using digital aerial photo analysis and GIS techniques for each 3-year interval. We abstracted beach DEM (digital elevation model) and ortho aerial photographs, and conducted a space analysis. As a result, we were able to identify changes in the area As a result, we drew 10 years cycle coastline change of Masan bay. and we can detect bay coastal line change and calculate refill rate.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.4
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• pp.229-239
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• 2019

A model of landslides is developed using the shallow water equations to simulate time-dependent performance of landslides. The shallow water equations are derived using the (b, s) coordinate system which can be applied in both river and ocean. The finite volume scheme employing the HLL approximate Riemann solver and the total variation diminishing (TVD) limiter is applied to deal with the numerical discontinuities occurring in landslides. For dam-break water flow and debris flow, numerical results are compared with analytical solutions and experimental data and good agreements are observed. The developed landslide model is successfully applied to predict subaerial and submarine landslides. It is found that the subaerial landslide propagates faster than the submarine landslide and the speed of propagation becomes faster with steeper bottom slope and less bottom roughness.

• Journal of Soil and Groundwater Environment
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• v.26 no.3
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• pp.1-13
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• 2021

Groundwater monitoring is commonly practiced with real-time sensors placed in several depth spots in aquifer. However, this method only provides monitoring data at the point where the sensors are installed. In this study, we developed a vertical line monitoring system (VLMS) that can provide continuous data of groundwater parameters along the vertical depth. The device was installed in a well located on the coast of the eastern part of Jeju island to monitor electrical conductivity, temperature, salinity, pH, dissolved oxygen, and oxidation-reduction potential over approximately 3 months from September 11 to December 3, 2020. The results indicated that the groundwater levels fluctuated with the tidal change of seawater level, and the upper and lower boundaries of the freshwater and saltwater zone in the groundwater were located at below 16 m and 36 m of mean sea level, respectively. There was a large variation in EC values during the high tide and temperature change was the greatest during flow tide. Although further investigation is needed for improvement of the device to obtain more accurate and reliable data, the device has a potential utility to provide fundamental data to understand the seawater intrusion and transport mechanisms in coastal aquifers.

• Journal of Navigation and Port Research
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• v.34 no.10
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• pp.781-786
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• 2010

In this study, a new concept of ocean transport system, called the mobile harbor serving for a short distance transport of containers with cargo handling cranes between mother containerships and coastal ports, is introduced. Instead of direct berthing a very large containership at the coastal port, Mobile Harbor is moving to the offshore mooring basin with enough water depth condition. Therefore, investigation of the coastal environment, technical condition and limitation of the domestic trade ports for the application of Mobile Harbor, is essential process. To figure out the accessibility of mobile harbor, the environmental conditions, the cargo handling capacity and marine traffic volume and flow pattern has been analyzed with the tools for marine traffic simulation and virtual navigation aids system. The most proper Mobile Harbor mooring areas among trade ports of the south and east coast are selected by analyzing the obtained information and evaluating its application: (1) Under natural environmental conditions such as air and sea weather, three candidate areas are selected such as Masan port, Ulsan port, and Busan(New port) port. (2) Under marine traffic and appropriateness of water facilities, three candidate areas are selected as Mokpo port, Busan(New port) port, and Donghae & Mookho port (3) For a region-based analysis considering handling capacity and the local managed trade ports in vicinity, three candidate areas are selected as Busan region, Yosu & KwangYang region, and Mokpo region. Through this study, the basic guideline for selection of optimum trade port and offshore mooring basin for mothership and Mobile Harbor is recommended. In order to apply the Mobile Harbor to the real water, navigaton aids as the virtual route identification with AIS must be introduced for maritime safety in the vicinity of Mobile Harbor area which berthing and cargo handling is being conducted.

• Journal of Environmental Science International
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• v.25 no.7
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• pp.1029-1042
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• 2016

The initial and boundary conditions are important factors in regional chemical transport modeling systems. The method of generating the chemical boundary conditions for regional air quality models tends to be different from the dynamically varying boundary conditions in global chemical transport models. In this study, the impact of real time Copernicus atmosphere monitoring service (CAMS) re-analysis data from the modeling atmospheric composition and climate project interim implementation (MACC) on the regional air quality in the Korean Peninsula was carried out using the community multi-scale air quality modeling system (CMAQ). A comparison between conventional global data and CAMS for numerical assessments was also conducted. Although the horizontal resolution of the CAMS re-analysis data is not higher than the conventionally provided data, the simulated particulate matter (PM) concentrations with boundary conditions for CAMS re-analysis is more reasonable than any other data, and the estimation accuracy over the entire Korean peninsula, including the Seoul and Daegu metropolitan areas, was improved. Although an inland area such as the Daegu metropolitan area often has large uncertainty in PM prediction, the level of improvement in the prediction for the Daegu metropolitan area is higher than in the coastal area of the western part of the Korean peninsula.