• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.10a
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• pp.124-126
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• 2015

해양수산부는 2013년 북극해항로 시범운항을 계기로 북극해항로 상용화에 대비한 운항전문인력을 양성하기 위해 한국해양수산연수원에 사업을 위탁하여 극지해역 운항선박에 승선하는 선장과 항해사를 교육대상으로 하는 Ice Navigation 기초 및 직무교육과정을 개발하였다. 이 개발과정 중 전문교원이 극지연구소 소속 쇄빙연구선 아라온호에 승선훈련을 실시하여 북극권 고위도 해역에서의 항해장비와 통신장비 특성 및 운용, 얼음 및 운항정보, 결빙해역 쇄빙 및 선박조종 특성 등을 직접 경험하여 확인한 정보를 공유하고자 한다.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.6
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• pp.353-364
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• 2020

This paper presents the semi-analytical ice load calculation methods that are useful to simulate the ice-breaking process. Since the semi-analytical methods rely on the previously developed closed form equations or numerical analysis results, the user's exact understanding for the equations must be supported in order to use the methods properly. In this study, various failure modes of ice such as local crushing, in-plane splitting failure, out-of-plane bending failure and radial or circumferential cracking with rotation of the broken ice floe are considered. Based on the presented methods, the fracture modes were evaluated according to the size and thickness of ice. In addition, time series analysis for the ice-breaking process was performed on several ice conditions and the results were analyzed.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.4
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• pp.306-312
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• 2018

To navigate in ice-covered waters, the ice-breaking process is required. The ice-breaking mode depends on material properties of sea ice and ice conditions. The ice-breaking mode is classified into ramming and continuous ice-breaking. The ramming is effective on large ice features, such as thick ice ridge and icebergs, and the continuous ice-breaking is on level ice. In general, the impact time duration of crushing or bending on ice sheets is from 0.2 to 1.0 second. However, impact duration in ramming will be increased. The Korean ice-breaking research vessel ARAON conducted her research voyage in the Antarctic sea during the winter of 2012. The IBRV ARAON measured strain in ramming and continuous ice-breaking. Strain gauge signals were recorded during the planned ice-breaking performance and the unplanned ice transits in heavy ice conditions. The aim of this study is to investigate the ice load signals measured in ramming processes under the heavy ice condition. Based on the time history of the signals, a raising time, a half-decaying time and time duration were investigated and compared with the previous study which was suggested the five profiles of the ice load signals.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.1
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• pp.23-34
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• 2020

This paper covers the development of prediction techniques for ice load on ice-breakers operating in continuous ice-breaking under level ice conditions using particle-based continuum mechanics. Ice is assumed to be a linear elastic material until the fracture occurs. The maximum normal stress theory is used for the criterion of fracture. The location of the crack can be expressed using a local scalar function consisting of the gradient of the first principal stress and the corresponding eigen-vector. This expression is used to determine the relative position of particle pair to the new crack. The Hertz contact model is introduced to consider the collisions between ice fragments and the collisions between hull and ice fragments. In order to verify the developed technique, the simulation results for the three-point bending problems of ice-specimen and the continuous ice-breaking problem around a wedge-type model ship with bow angle of 20° are compared with the experimental results carrying out at Korea Research Institute of Ships and Ocean Engineering (KRISO).

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.175-176
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• 2018

여름철 북극 해빙 면적의 감소 추세로 빙해선박의 북극항로 통항회수가 증가하고 있어 선박의 안전 항해를 위한 기술 개발에 관심이 집중되고 있다. 본 연구에서는 선박해양플랜트연구소에서 개발 중인 KRISO Arctic Safe Routing System(KARS)의 개념과 함께 핵심 모듈 중 하나인 빙저항 추진 성능 DB 개발 과정을 소개하였다. 우선 빙해수조에서 다양한 빙상환경(평탄빙, 유빙, 빙맥 등)에 따른 선박의 빙성능 평가 시험을 수행한 후 대상선박의 기본적인 빙성능을 도출하였고 빙성능 추정 S/W의 해석결과와 비교 검증을 수행하여 다양한 환경 변수를 고려한 빙저항 추진 성능 DB를 생성하였다. 아울러, 생성된 DB의 검증을 위해 2017년 8월 쇄빙연구선 아라온의 빙해역 실선시험 동안 계측된 결과와 비교 분석하여 정확도를 분석하였고 KARS의 개선 사항 및 향후 활용 가능성을 고찰하였다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.126-131
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• 2010

본 논문에서는 극지 빙해역을 운항하는 쇄빙선박이나 해양구조물에 작용하는 해빙의 재료특성을 계측할 수 있는 간이 실험 장비를 제작하였다. 극지 빙해역을 운항하는 쇄빙선박의 빙저항이나 해양구조물에 작용하는 빙하중을 추정하기 위해서 극지 현장에서 실규모의 시험을 수행하게 되는데, 저온과 얼음이라는 악조건을 극복하기 위한 빙역학 기술과 특수 장비가 필요하다. 국내에 한국해양연구원 MOERI 빙해수조가 완공됨에 따라 얼음의 특성을 고려한 모형빙 재료특성 시험용 계측장비가 일부 마련이 되었으나 빙해역 현장 시험에 대한 경험이 전무하며, 계측장비에 대한 지식과 기술 역시 확보되지 못한 실정이다. 본 연구에서는 차후 쇄빙연구선 ARAON호를 이용한 빙해역의 실선계측 시 해빙의 강도를 측정하기 위한 계측시스템 마련의 일환으로 시험편 획득을 위한 코어링 장비와, 해빙의 재료특성 중 1축 압축강도를 측정하기 위한 간이 압축시험기 그리고 얼음의 결정구조를 파악하기 위한 편광기를 제작하였다. 또한 극지 현장실험에 적용할 실험기법 확보를 위한 일련의 과정을 마련하기 위해 제작된 장비를 이용해 소양호에서 현장실험을 수행하였고 계측된 결과를 참고문헌과 비교해본 결과 유사한 값을 갖는 것을 확인할 수 있었다.

• The Journal of Engineering Geology
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• v.32 no.1
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• pp.113-126
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• 2022

The tectonic history of the Chukchi Abyssal Plain in the Amerasia Basin, Arctic Ocean, has not been fully explored due to the harsh conditions of sea ice preventing detailed observation. Existing models of the tectonic history of the region provide contrasting interpretation of the timing of formation of the crust (Mesozoic to Cenozoic), crust type (from hyper-extended continental crust to oceanic crust), and formation process (from parallel/fan-shaped rifting to transformation faulting). To help determine the age of the oceanic crust, the geothermal gradient was measured at three stations in the south of abyssal plain at depth of 2,160-2,250 m below sea level. Heat flow measurement stations were located perpendicular to the spreading axis over a 40 km-long transect. In-situ thermal conductivity measurement, corrected by the laboratory test, gave observed marine heat flows of 55 to 61 mW/m². All measurements were taken during Arctic expeditions in 2018 (ARA09C expedition) and 2021 (ARA12C expedition) by the Korean ice-breaking research vessel (IBRV) Araon. Given the assumption of oceanic crust, the results correspond to formation in the Late Cretaceous (Mesozoic). The inferred age supports the hypothesis of formation activated by the opening of the Makarov Basin during the Late Mesozoic-Cenozoic. This would make it contemporaneous with rifting of the Chukchi Border Land immediately east of the abyssal plain. The heat flow data indicate the base of the gas hydrate stability zone is located 332-367 m below the seafloor, this will help to identify the gas hydrate-related bottom simulating reflector in the future seismic survey, as already identified on the Chukchi Plateau. Further geophysical surveys, including heat flow measurements, are required to increase our understanding of the formation process and thermal mantle structure of the abyssal plain.