• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.53-58
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• 2006

Recently, vessel's average speed in the sea becomes fast because of the increasing of high-speeds vessel like a container ship and ferry. So, it is considered that speed control in the korean narrow waterway isn't the proper vessel traffic management, now. And, there is a rare paper studied about speed control quantitatively and numerically, especially speed control is discussing continuously, as abrogation of Incheon Port's speed control and alleviation of Kwangyang Port's speed control a according to navigating mariner's request. After this paper replayed the navigation traffic flow in the straight waterway using marine traffic flow simulation, the Environmental Stress Model is introduced to evaluate difficulty of each vessel's traffic.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.637-642
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• 2013

In this paper, an analysis results of towing force and towing points which are dominating factors to determine the behavior of towed ship are introduced. The towing force and towing points to achive the desired posture and its position of the towed vessel are derived based on simplified dynamics and linearization method. LQR algorithm for posture control is applied to linearized system and numerical simulation is also executed. Force based on COG(cneter of gravity) and gain of controller to achieve desired posture for target vessel are obtained by using Riccati matrix equation and pseudo inverse matrix is applied to analyze the relation between the derived force and its towing point. Based on this analysis method, towing force need to move the towed vessel from its initial position to target position can be calculated. The towing method including towing point and direction is also considered on this method. Finally, the relation between towing force and towing point is confirmed from the analysis and the results can be applied to arrangement of tug boats during salvage works.

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.689-694
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• 2014

The Korean government has introduced and enforced maritime traffic safety assessment to secure traffic safety since 2010. The maritime traffic safety assessment is needed by law to design a new port or modify an existing one. According to Korea Maritime Safety Act, in the assessment the propriety of marine traffic system consists of the safety of channel transit and berthing/unberthing maneuver, safety of mooring, and safety of marine traffic flow. The safety of channel transit and berthing/unberthing maneuver can be evaluated only by ship-handling simulation. The ship-handling simulation is carried out by sea pilots working with the port concerned. The vessel's proximity measure is an important factor to evaluate traffic safety. The proximity measure is composed of vessel's closest distance to channel boundary and probability of grounding/collision. What is more, the probability of grounding becomes important. According to central limit theorem, a sample has a normal distribution on condition that its size is more than 30. However, more than 30 simulation runs bring about the increase of assessment period and difficulty of employing sea pilots. Therefore this paper is to find out minimum sample size for evaluating vessel's proximity. First sample sets of size of 3, 5, 7, 9 etc. are selected randomly on the basis of normal distribution. And then KS test for goodness of fit and t-test for confidence interval are applied to each sample set. Finally this paper decides the minimum sample size. As a result this paper suggests the minimum sample size of 5, that is, the simulation of more than five times.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.576-584
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• 2022

AIS is widely utilized in vessel traffic services for marine traffic safety. In 2021, Korea deployed the high-speed maritime wireless communication system (LTE-Maritime) on the sea following IMO's proposal for the introduction of e-Navigation. In this paper, vessel trajectory data from AIS and LTE-Maritime were used for vessel trajectory prediction to compare and analyze the two systems. The results show that the trajectory prediction error of LTE-Maritime was smaller than that of AIS due to the granular and uniform data provided by LTE-Maritime. Additionally, it was revealed that time interval is the most important factor influencing the errors in trajectory prediction, with the prediction error of LTE-Maritime growing at a slower rate of 17% than AIS. This research contributes to the literature by quantitatively comparing AIS and LTE-Maritime systems for the first time.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.401-406
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• 2010

Vessel Operator has been navigating with subjective sate distance in accordance with night & daytime, fore & aft, port & stbd abeam and visibility situation. This sate distances may different depending on inside & outside harbor limit, current, wind and visibility situation. By now, the concept of proper sate distance between navigating vessels has been adopted in Korea, using the early 1980's foreign data. And the safe distance is being used with the same value without any consideration of inside & outside harbor and the kind of vessel. So it is necessary to evaluate or search proper distance concept based on different sate consciousness of Korean manners. This paper aims to develop the basic model for marine traffic evaluation and the new model of marine traffic congestion. Also this paper proposes the basic control guideline of vessel traffic service center. The result of this study showed that minimum sate distance should be 4.4L forward, 3.1L aft and 26L abeam in case of good visibility in daytime, considering various parameters such as visibility, day and night. Some differences Here found between the existing minimum sate distance and the new minimum sate distance derived from the result of this study.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.4
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• pp.354-361
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• 2016

While the amounts of oil spill caused by the VLCC Hebei Spirit indicated 2.5 times more than that of the VLCC Sea Prince, the economic, environmental, and social damages derived from the Hebei Spirit spill were estimated to be about 30 times greater than those from the Sea Prince incident. This study consolidates the appropriate justification for building a multi-purpose large oil spill response vessel to allow swift and efficient handling of catastrophic marine pollution events through an analysis of technical and economic feasibility of such a project. The result of the technical feasibility analysis illustrates that a hopper dredge and oil spill response vessel with a capacity of 4,000 tons should be more appropriate. The result of the economic feasibility analysis indicates that under the most conservative estimates the project appears to be slightly impractical, with a benefit/cost ratio of 0.82, in which self-help efforts, however, can facilitate the project. And medium to optimistic estimates present benefit/cost ratios are estimated to be 2.72 and 5.82 respectively, representing apparent economic feasibility.

• Journal of Korea Trade
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• v.25 no.2
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• pp.152-177
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• 2021

Purpose - This study analyses the excepted requirement and burden of proof of the carrier due to unseaworthiness through comparison between the marine transport contract and marine insurance contract. Design/methodology - This study uses the legal analytical normative approach. The juridical approach involves reviewing and examining theories, concepts, legal doctrines and legislation that are related to the problems. In this study a literature analysis using academic literature and internet data is conducted. Findings - The burden of proof in case of seaworthiness should be based on presumed fault, not proved fault. The burden of proving unseaworthiness/seaworthiness should shift to the carrier, and should be exercised before seeking the protections of the law or carriage contract. In other words, the insurer cannot escape coverage for unfitness of a vessel which arises while the vessel is at sea, which the assured could not have prevented in the exercise of due diligence. The insurer bears the burden of proving unseaworthiness. The warranty of seaworthiness is implied in hull, but not protection and indemnity policies. The 2015 Act repeals ss. 33(3) and 34 of MIA 1906. Otherwise the provisions of the MIA 1906 remain in force, including the definition of a promissory warranty and the recognition of implied warranties. There is less clarity about the position when the source of the loss occurs before the breach of warranty but the actual loss is suffered after the breach. Nonetheless, by s.10(2) of the 2015 Act the insurer appears not to be liable for any loss occurring after the breach of warranty and before there has been a remedy. Originality/value - When unseaworthiness is identified after the sailing of the vessel, mere acceptance of the ship does not mean the party waives any claims for damages or the right to terminate the contract, provided that failure to comply with the contractual obligations is of critical importance. The burden of proof with regards to loss of damage to a cargo caused by unseaworthiness is regulated by the applicable law. For instance, under the common law, if the cargo claimant alleges that the loss or damage has been caused by unseaworthiness, then he has the burden of proof to establish the followings: (i) that the vessel was unseaworthy at the beginning of the voyage; and that, (ii) that the loss or damage has been caused by such unseaworthiness. In other words, if the warranty of seaworthiness at the inception of the voyage is breached, the breach voids the policy if the ship owner had prior knowledge of the unseaworthy condition. By contrast, knowingly permitting the vessel to break ground in an unseaworthy condition denies liability only for loss or damage proximately caused by the unseaworthiness. Such a breach does not, therefore, void the entire policy, but only serves to exonerate the insurer for loss or damage proximately caused by the unseaworthy condition.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1265-1272
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• 2015

This study aims at comparison and analyzing of marine officer license system for fishing vessels between South Korea and New Zealand. It is urgently required to establish Republic of Korea-New Zealand mutual certification system for marine officers who are on board ships within applicable area given that New Zealand will force foreign fishing vessels within New Zealand area to reflag from 2016 in accordance with the amendment of Fisheries Act. Secondly, to compare and analyze systems between two countries will contribute to the preparatory work related to ratification STCW-F convention as New Zealand already have completed law amendment to adapt the convention. Maritime law of New Zealand, Seafarers Act and Ship Personnel Act of Republic of Korea were compared and analyzed as references. The result showed that an improvement to corresponding level to the international convention and development of safety training by vessel type, and job descriptions according to the license class are needed to Republic of Korea system. Furthermore, it is suggested to prepare specialized training for deckhands as required in STCW-F convention and standard fishing vessel officer training record for designated institute of education. Therefore institutional complementarity and framework is required as it is expected that the nations of fishing in piscary demand to reflag Korean deep-sea fishing vessels or to ratify the STCW-F convention.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.291-297
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• 2006

Recently it is a tendency that the use of the heavy fuel oil is investigated even from the middle&small class vessel in order to reduce the operating cost of vessel caused by with rise of international gas price. In this study, analyzed the physical & chemical properties and examined the effect of refining treatment and a fuel oil additive for MF30 fuel oil which is a mixture fuel oil mixed M.G.O and the heavy oil MF380 use to be possible in the middle&small class vessel. As a results, the effects of two of pre-refinery treatment methods as centrifugal purifier and heating & homogenizing system(M.C.H) are some feeble, but the pour point and the flash point came to be low more or less. The effect of property improvement which is caused by with the fuel oil additive did not appear positively.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.214-215
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• 2005

Naval equipments are installed and used for naval vessel with different environmental conditions comparing to the commercial vessel, for example, high engine power per ship displacement size, severe vibration and shock due to high running speed and explosion from naval gun's bombardment and underwater weapons. Therefore, those equipments must be installed on shipboard with small spaces, high ambient temperature around engine room and which are required be fabricated with high resistances of vibration, shock and heat resources. But in case of commercial vessel, the performances of their recent equipments naval have been improved continuously due to the technology development of domestic shipbuilding and shipboard equipment industries, together with the related fundamental industries i.e, metal, steel and electronic industries, to an international level since 1970. With these results, it became possible to unify the specifications of shipboard equipments for the commercial and military vessels(Dual-Use). In this study, vibration and shock test standards for the commercial and military vessels will be compared and reviewed technically.