• Journal of Advanced Research in Ocean Engineering
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• v.2 no.4
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• pp.179-191
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• 2016

As the demand for renewable energy has increased following the worldwide agreement to act against global climate change and disaster, large-scale floating offshore wind systems have become a more viable solution. However, the cost of the whole system is still too high for practical realization. To make the cost of a floating wind system be more economical, a new concept of tension leg platform (TLP) type ocean floating wind system has been developed. To verify the performance of a 5-MW TLP type ocean floating wind power system designed by the Korea Advanced Institute of Science and Technology, the FAST simulation developed by the National Renewable Energy Laboratory is used. Further, 1/50 scale model tests have been carried out in the ocean engineering tank of the Research Institute of Medium and Small Shipbuilding, Korea. This paper compares the simulation and ocean engineering tank test results on motion prediction and tension assessment of the TLP anchor.

• Journal of Ocean Engineering and Technology
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• v.31 no.2
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• pp.164-169
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• 2017

Studies were performed on an ARS using SDINS's RLG and the geomatic sensor. To develop the ARS, experiments were performed to determine the characteristics of the RLG and geomatic sensor. Based on the results, to reduce the angular position errors of the RLG, which accumulate from the angular velocity data, an algorithm was studied that uses the Extended Kalman filter (EKF) to compensate the RLG data and geomatic sensor data. To verify the performance of the developed algorithm for reducing the cumulative angular errors, experiments that included the developed EKF were performed. Through these, it was shown that a drastic reduction in the angular errors of the RLG were achieved.

• Ocean and Polar Research
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• v.42 no.4
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• pp.283-292
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• 2020

Oncaea prendeli Shmeleva, 1966 is redescribed here based on a specimen collected using a fine-mesh net in the epipelagic layer in the south sea of Jeju Island, Korea. The Korean specimen is generally similar to Mediterranean specimens in terms of morphological characteristics, but it shows a few minor differences in a slightly larger length-to-width ratio for the distal endopod segment of the antenna, a relatively shorter caudal seta IV, and additional ornamentation on the maxillule and maxilla. This species is distinguishable from the most similar congeneric species, O. tregoubovi Shmeleva, 1968, and three species of the genus Spinoncaea Böttger-Schnack, 2003 by the distal and lateral armature of the antenna, ornamentation on the female maxilliped, spine number on the endopod of leg 2, and proportional length of setae on the caudal ramus. Moreover, spine lengths on the exopods of legs 2-4 are proposed as new morphological characters for the identification of congeners. This is the first record of O. prendeli in Korean waters.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.146-156
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• 2020

Two High Tensile Strength Steel (EH47) plates with thickness of 70 mm were butt-welded together by multi-pass Submerged Arc Welding (SAW), also the hardness and welding residual stress were investigated experimentally. Based on Thermal-Elastic-Plastic Finite Element (TEP FE) computation, the thermal cycles during entire welding process were obtained, and the HAZ hardness of multi-pass butt welded joint was computed by the hardenability algorithm with considering microstructure evolution. Good agreement of HAZ hardness between the measurement and computational result is observed. The evolution of each phase was drawn to clarify the influence mechanism of thermal cycle on HAZ hardness. Welding residual stress was predicted with considering mechanical response, which was dominantly determined by last cap welds through analyzing its formation process.

• Journal of Ocean Engineering and Technology
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• v.31 no.1
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• pp.28-35
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• 2017

This paper introduces a GPS-aided dead reckoning algorithm that asymptotically estimates the heading bias error of a magnetic compass based on geodetic north, improves the position error accumulated by dead reckoning, and helps the estimated position of an AUV to represent a position in the NED coordinate system, by receiving GPS position information when surfaced. Based on the results of a simulation, the locational error was bounded with a modest distance, after estimating the AUV position and heading bias error of the magnetic compass when surfaced. In other words, it was verified that proposed algorithm improves the position error in the NED coordinate system.

• Proceedings of the Korean Society for Information Management Conference
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• 2014.08a
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• pp.203-207
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• 2014

아웃리치 서비스는 이용자에게 도서관에 대한 긍정적인 인식을 높이고 내부적으로도 새로운 활력을 불어 넣어주는 장점이 있다. 때문에 공공도서관 및 대학도서관에서는 이미 많은 선행연구와 사례들이 개발되어 왔다. 이 연구는 아웃리치 서비스에 대한 개념과 의의에 대하여 명확히 하고, 타관종의 아웃리치 서비스와 국내외 전문도서관 운영사례를 조사 분석함으로써, 전문도서관 아웃리치 서비스의 개선방안과 추진전략을 제시하는데 그 목적이 있다.

• Ocean and Polar Research
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• v.38 no.4
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• pp.271-286
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• 2016

We evaluate the temperature and salinity fields in the East Sea reproduced by the global ocean reanalysis data using HYbrid Coordinate Ocean Model (HYCOM for short). Temporal correlation of Sea Surface Temperature (SST) change between HYCOM and the Group for High Resolution Sea Surface Temperature (GHRSST) are higher in summer than winter. Though distributions of temperature and salinity in the HYCOM are similar to those from historical data (World Ocean Atlas 2013 V2), salinity in the HYCOM is lower (highter) in the region where the salinity is high (low). Temperature fields in the Ulleung basin of HYCOM are quite similar to those derived from Pressure-recording Inverted Echo Sounder (PIES), such as the correlation coefficient is higher than 0.7. This indicates that the HYCOM represents well the circulation and meso-scale phenomena in the Ulleung basin.

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.156-156
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• 2017

• Journal of Species Research
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• v.12 no.spc
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• pp.1-69
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• 2023

This study aims to establish a comprehensive, synthetic inventory system for the fauna and flora of Dokdo Island, Republic of Korea, which has been conducted by a specialized research group consisting of more than 50 experts. The research was conducted over five years(2015-2019) and supported by the National Institute of Biological Resources, Ministry of Environment, Republic of Korea. All possible publications on the fauna and flora of Dokdo Island over the last 68 years from 1952 to 2020 were reviewed. As a result, 1,302 species were found on Dokdo Island during the study period. An updated list of 1,963 species was created. This is expected to be of great help for the conservation and national publicity of important indigenous biological resources of Dokdo Island.

• Ocean and Polar Research
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• v.45 no.1
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• pp.23-31
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• 2023

The core of the foreign policy of the Yoon Suk-yeol government is the promotion of active economic and security diplomacy as indicated in Policy Tasks No. 98. To this end, economic consultative bodies such as Regional Comprehensive Economic Partnership Agreement(RCEP), Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), and Indo-Pacific Economic Framework (IPEF) are taking the initiative to respond to the formation of supply chain, human rights, environment, and digital-related norms, and actively support Korean companies' overseas expansion. Due to the nature of the Ministry of Oceans and Fisheries (MOF) as an organization established centered on the space of the ocean, the MOF faces difficulties in bringing the functions of other ministries into the space of the ocean. Considering the vision, objectives, and detailed plans of the MOF, the contribution of the MOF in the field of active economic security, one of the main foreign policies of the Yoon Suk-yeol government, is perhaps too obvious. However, since the re-launch of the MOF, the ODA budget for the oceans and fisheries sector is too small compared to other ministries, so even if new policy demands are discovered, there are many difficulties in implementing these policies in practice. Recognizing these problems, this paper examines the background and contents of foreign policies that have been promoted for the efficient promotion of RCEP, CPTPP and IPEF and introduces the areas of cooperation in the oceans and fisheries sector in these foreign policies.