• Coastal and Ocean
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• v.6 no.1
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• pp.51-57
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• 2013

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.3 s.14
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• pp.1-8
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• 2004

In this study, the change of the current in the coastal zone before and after the construction of Jeju new harbor was predicted by using the numerical model, which uses Hardy-Cross method. The numerical model was carried out for the present state, before the construction, and the state after the construction, and for the wave direction the NNW direction for winter and NE direction for summer were tested so that the seasonal change may be considered. The computation result shows that a large amount of the wave induced current was occurred when there were high waves coming in from NNW direction before and after the construction. Also, before the construction a longshore current occurred moving from the west to the east at the new harbor construction site so that it formed a rip current in the Hwabuk-dong front sea. And also, after the construction, the tip current produced changed into nearshore circulating current and a small circulating current appeared at the harbor entrance. On the other hand, at Samyang 4each, which is 3.0km away from the new harbor in the NE direction, shows that there was a longshore current occurred from the west to the east, which is in the opposite direction the new harbor, and the effect on the new harbor by sediment transport at Samyang beach is thought to be very small.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.3
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• pp.191-196
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• 2015

In this study, physico-chemical properties and heavy metal contents of sediment samples were determined to characterize the current pollution levels of the sediments. Ignition loss of the samples obtained from outside of the harbor was relatively lower than that from the samples obtained inside of the harbor. Heavy metal pollution was not serious except Ni. Concentrations of Ni for J1, J3, and J4 exceeded 16 mg/kg. Thus, these areas were classified as lowest effect level according to Ontario sediment quality guidelines. Evaluation of sediments pollution using $I_{geo}$ and R resulted as non-pollution for all considered metals, which indicated that no outer pollutants entered in the Jeju outport harbor. However, drastic increase of Cu concentrations was observed. Its concentration obviously increased toward the inside of the outport harbor. Therefore, careful attention and plan for the protection and remediation of sediments is required to maintain the cleanness of the Jeju outport harbor.

• Proceedings of the Korea Water Resources Association Conference
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• 2002.05b
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• pp.1129-1134
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• 2002

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.163-165
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• 2007

제주 외항의 2단계 항만시설 사업으로 동방파제, 동방파호안, 접안시설, 친수호안, 접속호안 등 2,374m 구간에 대해 방파제 내파 안정성과 반사파 저감을 위한 단면계획을 통해 설계에 반영하였으며 지반 침하 및 지진피해 최소화를 위한 구조물의 사용 및 내구성을 중대시켰으며, 특히 크루저 선박의 본격취항을 대비한 친수공간개념의 도입에 많은 노력을 기울였다. 대상 사업지는 지형적 특성상 복잡한 형태의 고파랑이 작용하므로 방파제의 설계파를 7.3m로 상향조정하였고, 방파제 제간부에 발생하는 충격쇄파압에 대한 안정을 확보하기 위해 소파블록 피복케이슨제를 적용하였다. 제주도가 가지는 국제적 위상에 맞추어 국제미항개발, 레저형 웰빙공간조성 및 제주항이 가지는 자연적 특성을 반영하여 친수 방파제와 호안 및 배후시설의 친환경적인 배려를 최대화 하였다. 해양 생태계 보호를 위하여 해조류 서식지 및 해중림 조성 등 생태복원계획도 수립하였다.

• Geotechnical Engineering
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• v.23 no.11
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• pp.46-52
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• 2007

• The Safety technology
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• no.88
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• pp.45-47
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• 2005

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2006.09a
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• pp.149-152
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• 2006

• Journal of the Korean Geotechnical Society
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• v.23 no.6
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• pp.103-114
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• 2007

Sands distributed in Jeju island's coastal areas, Korea, can be classified as silicate sand derived from volcanic rock, carbonate sand derived from shells, and mixed sands containing both silicate and carbonate sands. These three types of sands typically exist in Jeju coastal areas. Samples of silicate, carbonate and mixed sands were obtained from Samyang beach, Gimnyeong beach, and Jeju harbor area, respectively. Compression tests were conducted to assess the compression characteristics of these sands. As a result of these tests, each sand showed different behaviors. For Samyang beach sand, it appeared that initial compression is a larger than the other two sands. For Cimnyeong and Jeju harbor sands, however, the additional compression occurred after initial compression. This could result from the crushing, shattering, and rearrangement of sand particles. In addition, settlement behavior of Jeju harbor ground according to the construction stages was analyzed using the measured data. It showed that in addition to the initial elastic compression, a considerable additional compression occurred with time. The settlements of Jeju harbor ground were predicted by using the elastic settlement calculation methods (empirical methods) and the compression test method. The empirical methods, which did not consider the crushing, shattering, and rearrangement of particles could show smaller result than that occurring actually.

• Industry Promotion Research
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• v.9 no.2
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• pp.13-22
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• 2024

The purpose of this study is to derive passenger trends and change rates for each airline and identify directionality and synchronization phenomenon. Data by each airlines was collected from the National Statistics Forum of Statistics Korea, and we used a total of 156 monthly data from January 2011 to December 2023. In this study, the rate of change was calculated for domestic Full Service Carriers (Korean Air, Asiana Airlines) and Low Cost Carriers (Jeju Air, Jin Air, T'way, foreign airlines). As a result of the analysis, the correlation was found to be high for KOREA in that order: Asiana, Korean Air, Jeju Air, T'way, Jin Air, foreign airlines. The rate of increase was highest in that order: T'way, Jin Air, Jeju Air, foreign airlines, Asiana, Korean Air. In the Scatter analysis, Asiana and Korean Air showed a very strong synchronization with KOREA. In addition, Jeju Air, T'way, Jin Air and foreign airlines also showed the same direction toward KOREA to a certain degree. In the Box-Box Plot analysis, it was determined that each airline experienced a number of unusual sudden fluctuations due to the outbreak of COVID-19. Passengers have a wider range of choices due to the emergence of Low Cost Carriers, and as a result, expectations for airline service are increasing. Airlines will need to make appropriate environmental improvements to satisfy these needs for corporate development.