• Journal of the Korean Institute of Navigation
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• v.18 no.2
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• pp.19-40
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• 1994

Several factors can be chosen for evaluating seakeeping performance, such as deck wetness, propeller racing, slamming, rolling, vertical acceleration and vertical bending moment, in consi-deration of the safety of human being, cargo and ship. In fact, there are few developments for an evalua-tion method of seakeepting performance correponding with each ship's characteristics. The purpose of this paper is to develop an quantitative evaluation method of seakeeping performance according to ship types. The scope and the method of this study are as follow. (1) Obtain each response amplitude of ship's motion in waves by Ordinary Strip Method and apply it to short-crested, irregular wave for random process of the factors on seakeeping performance. (2) Define the evaluation index, the dangerousness, the maximum dangerousness and the evaluation diagram. (3) Figure out the different characteristics according to ship types by computer simulation of evaluating seakeeping performance. (4) Adopt vertical acceleration and one of rolling or lateral acceleration as the factors on seakeeping performance by clarifying the correlation of stochastic process. This study developed an evaluation method coincident with each ship's characteristics, and suggested a device for application to actual ship. This method might be useful in developing the practical system of seakeeping performance in accordance with ship types. The ship models for computer simulation are 175m container ship types, 93m tranning ship HANARA as passenger ship type, 259m bulk-carrier type and 164m pure car-carrier type.

• Korean Journal of Remote Sensing
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• v.38 no.4
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• pp.435-446
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• 2022

Identifying ship types is an important process to prevent illegal activities on territorial waters and assess marine traffic of Vessel Traffic Services Officer (VTSO). However, the Terrestrial Automatic Identification System (T-AIS) collected at the ground station has over 50% of vessels that do not contain the ship type information. Therefore, this study proposes a method of identifying ship types through the Random Forest Classifier (RFC) from dynamic and static data of AIS and V-Pass for one year and the Ulsan waters. With the hypothesis that six features, the speed, course, length, breadth, time, and location, enable to estimate of the ship type, four classification models were generated depending on length or breadth information since 81.9% of ships fully contain the two information. The accuracy were average 96.4% and 77.4% in the presence and absence of size information. The result shows that the proposed method is adaptable to identifying ship types.

• The Korean Journal of Emergency Medical Services
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• v.8 no.1
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• pp.179-187
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• 2004

The purpose of the study was to injury types in Daegu subway fire accident, Sampung department store collapse, Mokpo airport civil aircraft accident, and Buan sunken ship disaster. The conclusion obtained from these analyses are as following. 1. The total of victims were Sampung department store collapse(l440 people). Buan sunken ship disaster(355 people), Daegu subway fire accident(340 people), and Mokpo airport civil aircraft accident(110 people). 2. The total of dead people were Sampung department store collapse(502 people), Buan sunken ship disaster(287 people), Daegu subway fire accident(192 people), and Mokpa airport civil aircraft accident(66 people). 3. The total of injured people were Sampung department store collapse(938 people), Daegu subway fire accident(148 people), Mokpo airport civil aircraft accident(84 people), and Buan sunken ship disaster(67 people). 4. The major types of victims presented smoke inhalation such as coughing, dyspnea, and sore throat in Daegu subway fire accident. 5. The major types of victims presented crushing(multiple fractures), vertebral, and soft tissues injuries in Sampung department store collapse. 6. The major types of victims presented multiple fractures. In addition to, a lot of people showed vertebral injuries and shock symptoms in Mokpo airport civil aircraft accident. 7. The major types of victims presented drowning as well lots of hypothermia patients in Buan sunken ship disaster. There were a wide variety of types in human disaster. Therefore, the most important disaster training program need to each disaster aspect in the local emergency medical services system. Moreover, the emergency medical services personnel should be understand and training for injury types of each human disaster.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.56 no.2
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• pp.163-171
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• 2020

Engaged in trawling in limited fishing grounds with a number of fish schools could cause collisions between fishing vessels. Therefore, providing accurate maneuver information according to the situation could be regarded as essential for improving seafarers safety and fishing efficiency as well as safety of navigation. It is difficult to obtain all maneuver information through sea trial tests only, so a method through empirical formula is necessary. Since most empirical formulas are developed for merchant ship types, especially the characteristics of hull shape parameter like C_bB/L and dC_b/B etc. are clearly different between fishing vessels and merchant ships, this could occur estimation errors. Therefore, in this study, the authors have selected target fishing vessels and merchant ships and analyzed the characteristics of hull shape parameter according to the ship types. Based on this analysis, the empirical formula developed for the merchant ship type has applied to the target fishing vessels; it has verified through the turning motion simulation that the estimation error could be generated. In conclusion, it is necessary to include the characteristics of the hull shape parameter of fishing vessels in the empirical formula in order to apply the empirical formula has developed for merchant ship types to fishing vessel types.

• Journal of Ocean Engineering and Technology
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• v.7 no.1
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• pp.56-61
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• 1993

Standard values in graphic porms are presented for the ratio of added wave resistance to the sun of added wave and wind resistances in head sea for three ship types, tanker, container ship and passenger ship. The effect of ship length on the ratio defined above is investigated for the three ship types. Obique sea added resistance is determined using wave direction reduction factor. The factor is obtained from model test results and cubic spline interpolation technique.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.22-25
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• 2000

This paper introduces the ship propulsion system in different aspects. In fact there are many types to accomplish electric propulsion. The latest installations are based on fixed generator speed and motor speed control. The AC motor drive systems with synchroconverter cycloconverter PWM converter are chosen for the ship electric propulsion. The configurations of the ship electric propulsion. The configurationso of the ship electric propulsion system must be considered about following criteria : torque and speed performances redundancy cost harmonics available space and shape. This paper introduces possible configurations of the ship electric propulsion and the major and minor points.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.106-107
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• 2022

The ship type identification of the surrounding ship is important information for navigators and VTS officers since they can estimate the maneuverability and near-future route of the ships. However, it is more than frequent that the information is not provided due to transmission trouble and seafarers' unfamiliarity with AIS. Thus, this study suggests predicting ship types through the Random Forest classifier after preparing a training and test dataset that contains ship features and types. The AIS data for Ulsan coast in 2018 was used for this study. The method may provide the effect that many navigators and VTS officers discuss and share the experience of predicting ship types.

• Journal of Navigation and Port Research
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• v.27 no.6
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• pp.639-643
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• 2003

The emphasis is put on the detailed knowledge on manoeuvring characteristic for the safe navigation while avoiding terrible collision between ships and on the guideline to the design and operation of the ship-waterway system The numerical simulation of manoeuvring motion was carried out parametrically for different ship types, ship-velocity ratios, separation and stagger between ships. As for the calculation parameters, the ratios of velocity difference (hereafter, $U_2$/$U_1$ ) between two ships were considered as 0.6, 1.2, 1.5. From the inspection of this investigation, it indicates the following result. Considering the interaction force only as parameter, the lateral distance between ships is necessarily required for the ship-velocity ratio of 1.2, compared to the cases of 0.6 and 1.5 regardless of the ship types. Furthermore, regardless of the ship-velocity ratio, an overtaking and overtaken vessel can be manoeuvred safely without deviating from the original course under the following conditions: the lateral distance between two vessels is approximately kept at 0.5 times of ship-length and 5 through 10. degrees of range in maximum rudder angle. The manoeuvring characteristic based on this investigation will be very useful for keeping the safety of navigation from the practical point of ships design and traffic control in restricted waterways.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.169-177
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• 2019

It is very important to understand the intention of a target ship to prevent collisions in multiple-ship situations. However, considering the intentions of a large number of ships at the same time is a great burden for the officer who must establish a collision avoidance plan. With a distributed algorithm, a ship can exchange information with a large number of target ships and search for a safe course. In this paper, I have applied a Distributed Stochastic Search Algorithm (DSSA), a distributed algorithm, for ship collision avoidance. A ship chooses the course that offers the greatest cost reduction or keeps its current course according to probability and constraints. DSSA is divided into five types according to the probability and constraints mentioned. In this paper, the five types of DSSA are applied for ship collision avoidance, and the effects on ship collision avoidance are analyzed. In addition, I have investigated which DSSA type is most suitable for collision avoidance. The experimental results show that the DSSA-A and B schemes offered effective ship collision avoidance. This algorithm is expected to be applicable for ship collision avoidance in a distributed system.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.673-680
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• 2010

The effects of different auditory warnings on response time and accuracy were studied in a laboratory ship-bridge work environment. Subjective preference on the type of auditory warnings was also of a primary concern. Twenty five subjects were asked to select an appropriate button for the warning sound presented with three types of auditory warning (abstract sound, auditory icon, and voice alarm) and five levels of warning situation (fire, steering failure, collision, engine failure, and low power). Results showed that the response time and accuracy was significantly affected by the types of auditory warning. The voice alarm resulted in a higher accuracy and subjective preference, as compared to the auditory icon and abstract sound. Regarding the response time, auditory icons and voice alarms were equivalent and superior to abstract sounds. Actual or potential applications of this research include guidelines for the design of integrated ship bridge systems.