• Journal of the Korean Society of Marine Environment & Safety
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• v.2 no.S1
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• pp.7-25
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• 1996

The amount of Sea Casualty is increased by heavy sea traffic, increasing sea-borne cargoes, and superannuated vessels. This study analyzed the circumstance of ship salvage in Korean Salvage Units and management of Salvage Divers in Korea and other countries in order to make establishment of Ship Salvage Divers. This paper reputed the object, the necessity and the character of Ship Salvage Divers. For the purpose of study two parts are considered in order to analyze the environment of salvage divers(the circumstance of Sea Casulties and Ship Salvage). Under the present circumstance in Korea this development planning study may be restricted, but the effective planning to activate Korean Ship Salvage Diver is abstracted as follows; First, the political assistance of concerned government authority is needed. Second, establishment of new course, grade, certificate and licence for Salvage Diver is a Pre-requisite factor for the successful enactment. Third, establishment of Korean Ship Salvage Diving Center or School is strongly required.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.3
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• pp.696-705
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• 2015

Approximately 4,000 vessels including sea trial ships per day are passing, entering or departing from Korea coastal waterway. Sea trial ships have erratic navigating patterns such as quick turning, crash stop and do not communicate with other vessels in appropriate time, so sea trial ships are often to expose dangerous situation such as collision in heavy traffic area. To identify the sea trial vessel's risk factors, this paper surveyed marine traffic volumes for 7 days in Korea harbour & coastal waterway, and it analyzed marine accident rate and intended to identify the risk degree of passing vessels. After that, this researched how many sea trial ship's traffic and what is the sea trial risk among sea trial items. We also conducted survey questionnaire and identified risk factors of sea trial ship. So this paper aimed to enhance the safety of korea coastal waterway to prevent sea trial ship's marine accident.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.504-511
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• 2015

In this paper, the results of evaluating the passenger comfort due to the standard deviation of acceleration in vertical and lateral direction regarding the ship response in irregular wave by ordinary strip method in regular wave and energy spectrum using linear superposition theory in order to evaluate the motion of experimental ship are as follows. According to the results of ship response, it was possible to find that, in order to reduce the motion of ship, a ship operating in bow sea was more stable than in quartering sea. In the results of analyzing the standard deviation of acceleration in vertical direction according to each component wave pattern, when there was a wave length of 56m and an average wave period of 6 sec, most of cases showed the peak value. And among them, the standard deviation was 0.35 which was the highest in head sea. And in case of lateral direction, the maximum value was shown in a wave length of 100m and an average wave period of 8 sec. And it was 0.16 in beam sea and ${\chi}=150^{\circ}$. In the evaluation of passenger comfort due to standard acceleration in vertical and lateral direction, it was 80% in head and bow sea. On the other hand, it was shown to be 15% in follow sea. Accordingly, when the expected wave height in a sea area where a training ship was intended to operate was known, it was possible to predict the routing of ship. And altering her course could reduce the passenger comfort by approximately 50%.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.14-19
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• 2014

When a helicopter lands on a ship deck in high sea states, one of main difficulties is the ship motion by sea wave, In case of a manned helicopter, a pilot lands a helicopter on the deck during quiescent period of ship motion, which is perceived from different visual cues around landing spot. The capability to predict this quiescent period is very important especially for shipboard recovery of VTOL UAV in harsh environments. This paper describes how to predict heave motion of a ship for shipboard landing of a VTOL UAV. For simulation, ship motion by sea wave was generated using a 4,000 ton class US destroyer model. Heave motion of ship deck was predicted by applying auto-regression method to generated time series data of ship motion.

• The Journal of Bigdata
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• v.7 no.1
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• pp.89-97
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• 2022

Various efforts are needed to prevent accidents because ship collisions can cause various negative situations such as economic losses and casualties. Therefore, research to prevent accidents is being actively conducted, and in this study, new leading indicators for preventing ship collision accidents is proposed. In previous studies, the risk of collision was expressed in consideration of the distance between ships in a specific sea area, but there is a disadvantage that a new model needs to be developed to apply this to other sea areas. In this study, the density-based ship domain DESD (Density-based Empirical Ship Domain) including the environment and operating characteristics of the sea area was defined using AIS (Automatic Identification System) data, which is ship operation information. Deep clustering is applied to two-dimensional DESDs created for each sea area to cluster the seas with similar operating environments. Through the analysis of the relationship between clustered sea areas and ship collision accidents, it was statistically tested that the occurrence of accidents varies by characteristic of each sea area, and it was proved that DESD can be used as a leading indicator of accidents.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.318-320
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• 2018

When a ship sails on sea, it may be influenced by the environmental disturbance such as wind, wave, sea surface temperature, etc. These affect on the ship's speed, fuel consumption, safety and operating performance. It is necessary to find the optimal weather route of a ship to avoid adverse weather conditions which can put the crews in serious danger or cause structural damage to the vessel, machinery, and equipment. This study introduced how to apply A* algorithm based on sea trial test data for determining the optimal ship routes. The path cost function was modelled as a function of minimum arrival time or minimum energy depending on the time of various environment conditions. The specially modelled path-cost function and the safety constraints were applied to the A* algorithm in order to find the optimal path of the ship. The comparison of ship performances estimated by real sea trial's path and estimated optimal route during the voyage of the ship was investigated. The result of this study can be used to create a schedule to ensure safe operation of the ship with short passage time or minimum energy. In addition, the result of this study can be integrated into an on-board decision supporting expert system and displayed in Electronic Chart Display and Information System (ECDIS) to provide all the useful information to ship master.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.2
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• pp.430-436
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• 2014

Excessive motion of the ship in rough sea would affect body's fatigue, cognitive ability, motion sickness, and the proficiency of activity. Among them symptoms of motion sickness are similar to fatigue and nausea. Motion sickness causes sudden degradations of ability to perform tasks in physical and psychological aspects, and causes delays or failure in mental activity, and also takes a significant amount of time recovering. In this study, questionnaire for MSI(Motion Sickness Incidence) survey was taken for the students aboard the training ship of Kaya to the open sea far from land. Motion sickness analysis was performed as comparing the results of questionnaire based on sea state, incident angle, economical speed, and location in the ship.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.2
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• pp.110-118
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• 2015

Weather routing method is one of the best practices of SEEMP (Ship Energy Efficiency Management Plan) for fuel-efficient operation of ship. KR is carrying out a basic research for development of the weather routing algorithm and making a monitoring system by FOC (Fuel Oil Consumption) analysis compared to the reference, which is the great circle route. The added resistances applied global sea/weather data can be calculated using ship data, and the results can be corrected to ship motions. The global sea/weather data such as significant wave height, ocean current and wind data can be used to calculate the added resistances. The reference route in a usual navigation is the great circle route, which is the shortest distance route. The global sea/weather data can be divided into grids, and the nearest grid data from a ship's position can be used to apply a ocean going vessel's sea conditions. Powell method is used as an optimized routing technique to minimize FOC considered sea/weather conditions, and FOC result can be compared with the great circle route result.

• Korean Journal of Computational Design and Engineering
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• v.17 no.2
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• pp.71-78
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• 2012

Recently, the ratio of fuel cost to the operational cost of a ship is increasing according to the increase of the international oil price. Thus, many studies are being made to reduce the cost; for example, a method for acquiring the sea state information, a method for estimating fuel consumption, a method for determining the ship's optimal route, and so on. However, these studies were not incorporated together and being independently made in different fields. In this study, by improving and incorporating such studies, a method for determining a ship economic route based on the acquisition of the sea state and estimation of fuel consumption was proposed. To evaluate the applicability of the proposed method, it was applied to an optimal routing problem of the ocean area including many islands. The result shows that the proposed method can yield the economic route minimizing fuel consumption.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.1155-1160
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• 2005

In order to evaluate the safety of navigation at sea and the safety of mooring ship on berthing, it is necessary that the wave and wind induced ship dynamic motion should be measured in real time domain for the validity of theoretical evaluation method such as sea-keeping performance and safety of mooring. In this paper, the basic design of sensors is discussed and some system configurations were shown. The developed system mainly consists of 4 kinds of sensors such as three dimensional accelerator, two dimensional tilt sensor, two displacement sensors and azimuth sensor. Using the this measuring system, it can be obtained the 6 degrees of freedom of ship dynamic motions at sea and on berthing such as rolling, pitching, yawing, sway, heave, surge under the external forces.