• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.882-895
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• 1997

Changes in the benthic communities have been studied to investigate the environmental effects before and after the construction of Shihwa Dike in the West coast of Korea. It is suggested that sequential changes in macrofaunal assemblages progressed in two sucressional directions. In the Shihwa lake under the influence of organic enrichment. First, the appearance of 'azoic tone' or 'grossly polluted zone' developed in the area of less than 6 m in depth resulted from the severe dissolved oxygen depletion due to the eutrophication from the increased organic loading. Second, the 'polluted zone' characterized by the proliferation of the opportunistic species in organically enriched area, was found in the vicinity of the industrial discharges and nearby fluvial inputs. This benthic community succession in the Shihwa lake seemed to be caused by the various ecological events such as an eutrophication in this organically enriched environment after construction of the dike and other physico-chemical parameters like salinity and dissolved oxygen in the bottom water, which may be influenced by the irregular surface water discharge and dilution by outer seawater inflow through the water gate of the dike. On the other hand, the benthic communities in the outside of the dike showed that the species richness was more than doubled and the abundance increased almost seven times more than that before the dike construction. This may be a typical characteristics of the initial phase in benthic eutrophication, suggesting that an increased organic input area may have been reponsible for this faunal change in the study area.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1995.10a
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• pp.139-140
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• 1995

The reclamation area of Saemangeum(Kunsan) located between 126。10´E - 126。50´ E and 35。35´N - 36。05´N at the western coast of Korea. The construction of the 33km sea dike is building in the Saemangeum area. When the construction of the sea dike in the coastal region takes plase, there exists, a certain amount of soil which is diffused by the tidal current. (omitted)

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.419-424
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• 1998

The deduction methods for forced displacement depths caused by sea dike construction often assumed the shape of forced displacements and heaving. To investigate the shape of forced displacements and heaving, a model tests was performed. Results of the tests are as follows; 1) The shape of forced displacements can be assumed ellipse. 2) The shape of heaving can not be assumed uniform shape like a circle and Extents of heaving was varied with the loading height and width. 3) The shape of forced displacements caused by step construction, pebble embankments and soil embankments, also investigated.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.66-71
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• 2000

This study was carried out to investigate the changes of tide velocity and sea bottom topology during the construction period of sea dike. The tide velocity and sea bottom depth were measured in Saemangeum area every year, and analyzed and compared to the initial data. The current and future changes of the tide velocity and direction according to the construction of Saemangeum sea dike were presented.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.6
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• pp.453-461
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• 2009

Camera monitoring of topographical changes of intertidal flat was performed at Daehang-ri mud flat outside Semangeum sea dike No. 1, where creation of mud flat was reported after sea dike construction. Ground survey on the mud flat is often limited only to points or few line surveys because of difficulty of walking and limitation of working hours by flood/ebb. This study uses natures of tide that the water lines moving on the intertidal flat during a flood indicate depth contours between low and high tide. Ground coordinates for the water lines extracted from the consecutive images of intertidal flat are calculated and information of topography is acquired by integrating all the water line data. Analysis of 6 camera monitoring data between September 2005 and September 2009 shows 0.127 m deposition per year on the average and variation of deposition/erosion in space and time.

• Journal of the Korean Geosynthetics Society
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• v.10 no.3
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• pp.53-62
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• 2011

This paper presents the characteristics behavior of dike structure and foundation ground through the shaking table model test. The vibration loadings of design earthquake acceleration of 0.154g was applied to this laboratory model test regarding on dike structure and foundation ground under the structure. The model was formulated with 1/100 design of representative cross section for evaluating the effectiveness of vibration. Based on the test results, we can analysis the behavior of lateral displacement and settlement characteristics of structure under the earthquake loading. The pore water pressure was also monitored in the upper, middle and lower layers of ground. Finally, the actual displacements and pore water pressure of the structure can be predicted by using the results of the laboratory shaking table test.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.2
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• pp.136-144
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• 2009

This paper focuses on the attempt to manual application for optimization structural scale of stone and Gabion at the closing gap of sea dike. The manual was developed through hydraulic model experiment that measured the critical velocity of sill-crest, bottom protection and dam-face at the final closure of Saemangeum sea dike, and through the comparison and verification of critical velocity for each scale calculated by existing empirical formula. Also, the critical velocity when rocks are used together with gabion is measured to add to the manual, which is an initial attempt that had not been executed before. The manual proposes the appropriate structural scale according to the measured critical velocity per day during the final closure period of Saemangeum sea dike, and its application was appraised highly after the completion of the final closing.

• Fire Science and Engineering
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• v.33 no.4
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• pp.97-104
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• 2019

Behind the growth of the chemical industry which is a cornerstone of the Korean economy, dozens of hazardous and noxious chemical accidents occur every year, resulting in enormous casualties and environmental damages. Many cases among chemical accidents are caused by the carelessness of workers in handling facilities such as hydrochloric acid and hydrofluoric acid, and the aging of handling facilities. In order to mitigate the damage by such chemical accidents, a safety system for preventing atmospheric diffusion of hazardous and xoxious chemicals in dike was proposed. The atmospheric diffusion prevention safety system consists of leak detection phase, alarm and measurement phase, suppression and blocking phase. Through the proposed the atmospheric diffusion prevention safety system, the need for 2nd chemical accident prevention such as atmospheric diffusion in dike can be posed.

• Fire Science and Engineering
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• v.33 no.4
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• pp.121-129
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• 2019

The Chemical Control Act of 2015 was enhanced to ensure the safe management of hazardous chemicals. In particular, there have been substantial changes in the standards for the installation and management of handling facilities for manufacturing and storing hazardous chemicals. However, some standards for handling facilities are difficult to implement due to a lack of physical space or because of safety accidents during facility improvements. Therefore, the Safety assessment system (SAS) has been operating for such facilities since 2018. This study developed a leakage trajectory evaluation module that can easily evaluate the outside of a dike for safety evaluation. We analyzed two case studies on a dike for hydrochloric acid and sulfuric acid storage tanks with this module and suggest a reasonable plan for the facility. We believe that it will be possible to more easily submit SAS reports at chemical plants by using this evaluation module. This study is expected to contribute to the improvement of the safety design of hazardous chemical handling facilities.

• Journal of Korea Water Resources Association
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• v.46 no.12
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• pp.1157-1167
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• 2013

Sayeon dam is the one that is structured in 1965 and supplying residential water in Ulsan. The hill located within the reservoir near the entrance of the dam spillway plays a role as a natural Dike. According to the recent surveys on change of sediment and effective volume of water kept in store, the latter that decreased 2.92% from twenty million tons and the former increased just 1.65 m. In this survey we examined the application of SED-2D model using measured data of Sayeon dam sediment. In addition we surveyed the inflow control and the water depth to be kept when installing small hydraulic structure similar to Dike around the dam reservoir entrance. To do this, we simulated the hydraulic effects and sediment on the conditions eliminating the hill or installing the structure higher than it. The controlling effects of present hill or adding small hydraulic structure on it was found, though the changes of the measure was not large.