• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.1
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• pp.11-18
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• 1993

A key element of a successful search and rescue is the correct prediction of the target location. In this paper, new computer models for drift prediction are suggested from the analysis of several methods currently used in other countries. Depending on the availability of the environmental data, users may select a model between the modified versions of U.S. Coast Guard CASP and FLENUMWEACEN SAR. Targets include boats, life rafts and person in water. Life rafts and boats are further classifed. New models are tested and compared with the limited number of field experimental results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.73-80
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• 2004

Recently, many maritime accidents have been increased and the collisions due to human error are given a great deal of proportions out if them We develop the Real-time Collision Risk Monitoring System (CRMS) for the navigational officers to cope with the emergency situation promptly and thus to reduce the probability if casualty. In this study, the risk of collision is evaluated by two kinds if method. The first method is based on Fuzzy algorithm, which evaluates the risk of collision between traffic ships. The second method is based on Environmental Stress (ES) Model, where the total risk if collision is evaluated by the environmental stress felt by human. The developed real-time CRMS has been installed to the ship handling simulator system and its capabilities have been tested through simulator experiments.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.4
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• pp.21-31
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• 2001

When an oil-spilling accident occurs at sea, it is of the primary importance to predict the amount of oil leakage for the swift response and decision-making. The simplest method of oil-leakage estimation is based on the hydrostatic pressure balance between oil inside the tank and seawater outside of leakage hole, that is the so-called Torricelli equilibrium relation. However, there exists discrepancy between the reality and the Torricelli relation, since the latter is obtained from the quasi-steady treatment of Bernoulli equation ignoring viscous friction. A preliminary experiment has been performed to find out the oil-leaking speed and shape. Soy-bean oil inside the inner tank was ejected into water of the outer tank through four different leakage holes to record the amount of oil leakage. Furthermore, a CFD (Computational Fluid Dynamics) method was utilized to simulate the experimental situation. The Wavier-Stokes equations were solved for two-density flow of oil and water. VOF method was employed to capture the shape of their interface. It is found that the oil-leaking speed varies due to the frictional resistance of the leakage hole passage dependent on its aspect ratio. The Torricelli factor relating the speed predicted by using the hydrostatic balance and the real leakage speed is assessed. For the present experimental setup, Torricelli factors were in the range of 35%~55% depending on the aspect ratio of leakage holes. On the other hand, CFD results predicted that Torricelli factor could be 52% regardless of the aspect ratio of the leakage holes, when the frictional resistance of leakage hole passage was neglected.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.1
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• pp.70-75
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• 2000

It is important that effective and rapid response should be taken in the initial stage of the tanker accidents. A towing simulation system is essential to train in-site salvors for tile effective response in the tanker accidents. Training this system will help the marine environment to be protected from the oil pollution which could be proceed further by the secondary accidents. It this study, the towing simulation system using the TIS(Towing vessel Information System) was established, and ground reaction force was calculated using the simplified methods. This system will be useful for evaluation of towing procedures of oil tankers in stranding.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.6
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• pp.591-596
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• 2012

Recently, a vessel's maneuvering performance is considered to be an important subject to secure safety at short sea shipping. Especially the high turning performance, which is required to avoid the marine pollution by the ships that was grounded, becomes more severe. In this paper, we discuss the effect of increasing rudder force on turning performance of short sea shipping ship by free running test in towing tank. First of all, we make the 47K PC model ship and high-lift rudder using Coanda effect. And we make the free running test system for the turning test in towing tank. And also we perform the turing test of 47K PC model in several changes of Coanda jet momentum and evaluate the turing performance such as advance and tactical diameter. Finally, we confirm that the increasing of rudder force is very effective to improvement of turning performance of short sea shipping ship.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2000.05a
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• pp.59-64
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• 2000

Active radar reflector may be less familiar, since their uses have been limited to military applications, especially the enhancement of the effective radar cross-sections of missile test range in the drone aircraft and missiles. Perhaps the most widely-blown applications of radar transponders are Identification Friend or Foe(IFF) and its civilian counterpart, secondary surveilliance radar for Air Traffic Control(ATC), and most recently, as Search And Rescue Transponder(SART) in the Global Maritime Distress and Safety System(GMDSS). Since it happens frequently accidents on the sea, the problems of the contamination more seriously considered. The conventional navigation buoy and utilities are not sufficient to maintain the safety of the sea and thus new structured concept must be considered. Therefore, this paper propose and implement the active radar reflector with a enhanced structure. The results are shown that the performance of the system is significantly improved comparing with the conventional utilities.

• Journal of the Korean Institute of Navigation
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• v.9 no.1
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• pp.1-40
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• 1985

The transport of cargoes carried by coastal and ocean-going vessels has increased with the rapid growth of the Korean economy these days. This increase of the sea-borne cargoes has made the Korean coastal traffic so congested that this can be a cause of large pollution as well as great marine casualties such as loss of human lives and properties. Marine casualties generally result from the complicated interaction of natural and human factors; the former being the topographic, marine traffic volume and meteorological conditions, and the latter being the quality of seafares. In this paper, the authors analyse the trend of marine casualties in the Korean coastal and clear up the cause of accidents and examine closely the mutual relations among sea accidents, weather conditions, and marine traffic volume. These accidents are classified into several patterns on hte point of view of ship's size, ship's type and ship's age and its characteristics of each pattern are described in detail. Also, the authors estimate the amount of economical losses resulting from marine casualties which are classified into the accident patterns, and clarify the effects of those losses on B/B(Balance Sheet) and P/L(Profit & Loss) of Korean shipping companies and Korean national economy. The analyzed results of marine casualties are summarized as follows: 1) The average number of sea accidents is 248 cases per year with the loss of 107 persons during last 13 years. 2) Collision is the top of causes of sea accidents (approx. 36.4%), shipwreck the second (approx. 20.3%), agroung the third rank (approx. 18.2%). 3) The ship's number under 1, 000G/T is approx. 74% of total ship's number of accidents. 4) 80% of total number of marine accidents is taken plact at the coastal waters. (involved ports & narrow channels) 5) Marine casualties are occur likely to in the night, the winter and the summer. 6) The average amount of economical losses is approx. 18.5 billion won. (approx. 0.14% of GNP) 7) Shipwreck is the top of the amount of economical losses (approx. 60.4%), collision the second (aprox. 24.5%), aground the third (approx. 9.9%). 8) The amount of economical losses is approx. 5.24% of gross capital of shipping co., 1.24% of shipping revenue, 1.38% of shipping total income in 1983.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2007.12a
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• pp.75-76
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• 2007

A mis-handling of the ship operators show high rate among the whole marine accidents. Since the port conditions have been getting worse. also as her size and speed increase, collision risk has been increased so that ship needs the automatic control system for collision. From that purpose, this research has been proceeded. The research has based on the MMG mathematical model, used Surge-Sway-Yaw motion equation, the information from the position and estimated time of collision point (DCPA and TCPA) to determine the collision risk with Fuzzy theory. To verify this system, ship was simulated when the ship encountered multitude of ships around the coast. The simulation result shows good application in avoiding ship collisions around the coast.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.4
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• pp.303-307
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• 2008

The tug boat is restricted in her maneuvering ability due to the towed barge, and tug-barge has been strongly affected by the external forces, i.e. the wind, wave, currents, and so on. Therefore, it is difficult to get the safety of tug-barge operation. It is necessary for the captain of tug boat, VTS and operation department to develope the system which can keep observing the course, speed and position of the towed barge in actual sea and prevent the marine accidents in advance. In this study, we proposed the basic method to develope the safety towing system for barge using portable GPS which was easily movable and relatively inexpensive. Then we conducted the test on the real barge. As a result, we could obtain diverse navigation data to make a safety towing work. It was noted that these data could be used for carious purposes.

• Journal of the Korean Institute of Navigation
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• v.25 no.2
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• pp.195-205
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• 2001

It has been over seven years since Maritime Code of the Peoples Republic of China (hereinafter called the Code) came into force on July 1st 1993. During this period it has played a very important roll in governing Chinas ocean shipping. However, owing to the defects of the Code, many problems have arisen in the performance of the Code, among which is the problem related to delay in delivery. Therefore, it is necessary and inevitable to revise the Code. This study is limited to a rough study on the regulations related to delay in delivery in the Code, such as the definition of delay in delivery, the carriers responsibility for delay in delivery, the carriers exemption from responsibility for delay in delivery, the limitation of responsibility, the procedures of claims for delay in delivery and the difference of the Code from the Korea Commercial Law, the Hague Rules, the Hague-Visby Rules and the Hamburg Rules. Furthermore, some defects in the Code are pointed out and suggestions are provided for the revision of the Code.