• Journal of Ocean Engineering and Technology
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• v.20 no.3 s.70
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• pp.77-81
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• 2006

In this study, design parameters of ice-transiting vessels in the world, currently in service or under construction, were collected and a database of principal particulars for each ship was established. To understand the recent design trend, ice-transiting vessels were categorized into four groups, i.e., conventional icebreakers, icebreaking tug/supply/research vessels, ice-strengthened passenger/car ferry and ice-strengthened cargo vessels. Changes in principal particulars for each group were reviewed and summarized. It was found that the most significant change in the design of ice-transiting vessels was the increment of large size commercial cargo vessels. It is believed that the recent hike of oil prices and booming of Russian economy has resulted in the need for year-round operation with bigger ships in the Baltic Sea and in the Sea of Okhotsk and also along the Northern Sea Route in Russian Arctic Sea.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.2
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• pp.151-164
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• 2021

With the gradual increase in the ROK naval power, it is an undeniable fact that the time of operation in the ice-infested area will be necessary in the near future. Recently, cases of ice formation around Korean waters in wintertime have been frequently reported. However, in the case of the ROK naval vessels to date, it is a fact that the ice-strengthened perspective has not been considered from the design stage. In this study, the capability of operation in the ice-infested area of the ROK naval vessels, which did not take into account the ice-strengthened design, was reviewed through the evaluation of the vessel's structural integrity in accordance with the sea ice conditions.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.2 s.146
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• pp.147-155
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• 2006

Ice resistance estimation equations based on model tests and full-scale sea trial data from many previous research articles are studied. Measured ice resistance data and its empirical/semi-empirical estimation equations are summarized in common format and are compared with each other, considering three ship categories, i.e, icebreakers, tug/supply vessels, ice-strengthened cargo vessels. The most suitable estimation methods or prediction equations are recommended based on this ice resistance data analysis.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.6
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• pp.575-580
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• 2011

Icing problem of ice-strengthened vessels is an important issue when operating in low temperature environment and it can cause damage to deck machineries and emergency equipments. Many ice-strengthened vessels have since been constructed and operated in accordance with the ice class rules such as Det Norske Veritas (DNV), Russian Maritime Register of Shipping (RS), American Bureau of Shipping (ABS) and so on. Therefore winterization is defined as the preparation of a ship for safe operation. In this research, anti-icing performance tests of weather-tight door have been carried out at various temperature conditions($5^{\circ}C$, $-10^{\circ}C$, $-20^{\circ}C$, $-30^{\circ}C$, $-40^{\circ}C$) in the low temperature cold room facility and then, ambient temperature, specimen temperature, electric current and temperature of heating cable were measured during the test operations. This research describes the construction guidelines of weather-tight door based on anti-icing test results to apply to the full-scale vessels.

• Journal of Ocean Engineering and Technology
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• v.19 no.6 s.67
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• pp.50-57
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• 2005

Ice resistance on ice-transiting vessels is one of th￡ important issues concerning th￡ design of ships with ice classes. In this study, th￡ development of GUI software for estimation of ice resistance on ice-transiting vessels is discussed. lee resistance estimation equations, based on model tests and full-scale sea trial data from many previous research articles, are studied in conjunction with two ship categories i.e., ,icebreakers/supply/tug vessels and ice-strengthened cargo vessels. lee resistance estimation equations are summarized in common format and are compared with each other. The GUI software 'Ice View,' written in MS Visual Basic language, can calculate ice resistances according to varying ice thickness and ship speed. The software can provide the calculated results, with suitable tables and graphs, for easy comparison of each ice resistance estimation equation.

• Journal of Ocean Engineering and Technology
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• v.35 no.5
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• pp.369-381
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• 2021

The International Ice Patrol (IIP) was established after the Titanic collided with an iceberg off the eastern coast of Canada in 1912 and sank, killing more than 1,500 people. Recently, the IIP has analyzed satellite images and provided safe operation information to vessels by tracking the occurrence and movement of icebergs. A large number of recent arctic studies mainly deal with sea ice formed by freezing seawater related to sea routes and resource development. The iceberg that collided with the Titanic was land-based ice that dislodged from a glacier and fell into the sea. The properties of these two types of ice are different. In addition, vessels operating in ice-covered waters such as the Arctic sea have an ice-breaking function or minimum ice-strengthened functions. Ships operating on transatlantic routes including the eastern coast of Canada do not necessarily require ice-strengthened functions. Hundreds to thousands of icebergs are discovered each year near the area where the Titanic sank. In this study, the status of ship-iceberg collision accidents was investigated to provide useful information to researchers, and the physical and mechanical characteristics of icebergs were investigated and summarized.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.1
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• pp.22-27
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• 2018

Ships strengthened for navigation in ice encounter level ice, ice ridge and broken ice fields. Thus, the ship resistance in ice is a very critical concern to the designers of ice-going vessels. The objective of this study is to understand the physical aspects of ship performance in ice and to investigate the characteristics of the ship resistance in broken ice channels. In particular, this study identifies the ship resistance in ice associated with the broken ice channel width and the size of broken ice pieces. Model testings of towed-resistance condition in broken ice channels with three ship speeds were conducted in KRISO ice model basin. The influence of the ship resistance characteristics in broken ice channels for channel width and size of broken ice pieces was analyzed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.40-46
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• 2017

Shipping activities have become possible in the Arctic Ocean due to melting ice by global warming. An increasing number of vessels are passing through the Arctic Ocean consequently bringing concerns of ship-iceberg collisions. Thus, most classification societies have implemented regulations to determine requirements for ice strengthening in ship structures. This paper presents the simulation results of an ice-strengthened polar class ship after an iceberg collision. The ice-strengthened polar class ship was created in accordance with the Unified Requirements for a Polar-Ship (IACS URI). An elastic-perfect plastic ice model was adopted for this simulation with a spherical shape. A Tsai-Wu yield surface was also used for the ice model. Collision simulations were conducted under the commercial code LS-DYNA 971. Hull deformations on the ice-strengthened foreship structure and collision interaction forces have been analysed in this paper. A normal-strength ship structure in an iceberg collision was also simulated to present comparison results. Distinct differences in structural strength against ice impact forces were shown between the ice-strengthened and normal-strength ship structures in the simulation results. About 1.8 m depth of hull deformation was found on the normal ship, whereas 1.0 m depth of hull deformation was left on the ice-strengthened polar class ship.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.6
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• pp.450-457
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• 2013

For the design guide of a vessel operating in cold region, numerical analysis was carried out to evaluate the weather-tight door which installed the heating cables by using ANSYS 13.0 Transient Thermal. The numerical analysis was performed by considering Advection-Diffusion equation. This study based on the experimental results of 'A study on Anti-Icing Technique for Weather-Tight Door of Ice-Strengthened Vessels'(Jeong, et al., 2011a) in KIOST. For validation of the numerical analysis results, the cold chamber experimental data measured by the heat sensors in certain location of the weather-tight door was used. The external environmental temperature which varies from $5^{\circ}C$ to $-55^{\circ}C$ was considered in numerical analysis. Also three different heating cables which have the heat capacity of 33W/m, 45W/m and 66W/m were adapted for the design parameters to be the most efficient and guidelines for anti-icing design of the weather tight door.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.4
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• pp.323-329
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• 2015

For the design guide of a vessel operating in cold region, numerical analysis was carried out to evaluate the ice class louver which installed the heating cables by using ANSYS 13.0 CFX. The numerical analysis was performed by considering Unsteady Reynolds Averaged Navier Stokes (RANS) equation. This study based on the experimental results of ‘The Cryogenic Performance Evaluation for the Excellent De-icing Ice Class Louver’ in KRISO. For validation of the numerical analysis results, the cold chamber experimental data measured by the heat sensors in certain location of the ice class louver was used. The external environmental temperature which varies from 0℃ to –30℃ was considered in numerical analysis. Also the design guide for optimum de-icing presented through heating cable power capacity(33 W/m, 45 W/m, 66 W/m), location of the heating cable(front, center, behind on the blade) and relative velocity(1 m/s, 4 m/s, 7 m/s).