• Journal of Navigation and Port Research
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• v.32 no.8
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• pp.569-576
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• 2008

By the development of international trade in last decades, Korean International Trade has been grown rapidly and Korean Port and Port facilities have been improved stimultaneously: finally volume of the marine traffic increased rapidly. Presently, 15 VTS centers have serving in Korean waters and since the introduction of the first VIS Center in Korea there is no quantitative analysis to find workload of VIS operator. After that Port-MIS and De-brief data have been gathered for 7 days and inbound-outbound vessels time-g/t table prepared and traffic volume examined for each V1S center. Hence $L^2$ conversion traffic volume and dangerous vessel ratio obtained Later on conversion controlled number obtained by denoting ratio 1.0 to directly controlled vessels by VTSO and denoting ratio 0.3 to indirectly controlled vessels by VTSO. Traffic volume, large vessel ratio, dangerous vessel ratio, dimension of VTS controlled area, marine accident occurrence frequency and communication volume of comm. log can be counted as a factor which influence to workload of VTSO. All those factors have been examined and analyzed. Finally, ship's size and dangerous vessel ratio have been chosen to derive the Number of composite conversion control for workload formula.

• Journal of Navigation and Port Research
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• v.46 no.1
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• pp.18-25
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• 2022

MOF strengthen the law and institutions for safety management after the capsize accident of passenger ship "Sewol" on April 16, 2014. Nevertheless, about 13 cases of marine accidents such as collisions, contact, and stranding have occurred in coastal passenger ships over the past 5 years. Particularly, according to the judgment of KMST, most of the main causes of passenger ship accidents occurred within harbor areas because of the master's improper ship-handling or inattention. And so, this study analyzed four cases of marine accidents on passenger ships that occurred in the port areas and examined the environmental, institutional, material, and human factors that contributed to the master's improper ship-handling and behavior, and the results are as follows. First, as an environmental factor, the size of the turning basin was not enough. Second, as an institutional factor, the VTS control was not properly supported, the master lacked sufficient training for safe ship-handling in the port area and up-to-date charts were not provided. Third, as a material factor, the digital type speed log capable of the ship's speed in real-time was not installed on the ship's wing bridge. Lastly, as a human factor, the master could not take proper bridge resources and the passage plan was not proper. Therefore, it is suggested in this paper that the size of the turning basin should be adjusted to meet the prescribed standards, the master of passenger ships should receive the ship-handling simulation training among other safety training to ensure safe ship-handling of the master in the port area as improvement measures.

• 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 the Korean Society of Marine Environment & Safety
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• v.17 no.3
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• pp.227-233
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• 2011

Korea coastal area is highly potential dangerous zone of marine accident due to frequent ship's encounters. VTS center can't identify ship's information because of beyond VHF range. It is also difficult of us to efficiently manage vessel traffic beyond VTS control area, so that it can't prevent marine accident. Presently, korean government is conducting maritime traffic safety assessment according to enlargement of harbor & development of new port but do not have the system which provide danger of information depending on maritime traffic environment with real time. So it is necessary to develop evaluation index which can assess sea risk through the evaluation of maritime traffic environment. In this paper, on the basis of vessel navigator's risk consciousness, we carried out survey & statistical analysis vessel navigator's subjective risk depending on the LOA, crossing situation($045^{\circ}$, $090^{\circ}$, $135^{\circ}$), overtaking, head-on situation, encountering vessel's side, within or outside harbor, speed with other vessel(ex. same, fast or slow), speed difference with other vessel and distance with other vessel & propose basic expression to develop maritime traffic safety evaluation model. And by using this model, we can confirm that this proposing expression is suitable for domestic maritime traffic environment.

• Speech Sciences
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• v.14 no.3
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• pp.21-29
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• 2007

The necessity for improving the English listening ability of Korean learners has been emphasized since the ultimate goal of English education converted to CLT(Communicative Language Teaching) in Korea. Verbotonal Approach as an auditory-based strategy has been proved to be effective substantially in maximizing the listening skill of spoken foreign language. The purpose of this study is to find out an efficient way of improving listening ability for Korean middle school students by employing OFH(Optimal Frequency of Hearing) using Tonality Word Sentence Test, before & after using Listen II Verbotonal training unit based on VTS(Verbotonal System). The results of the listening tests showed that the listening ability of the subjects increased by 16.7% on the words and by 5.5% on the sentences after using Listen II, compared with before using Listen II and that the improvement rate of listening ability on the level of words is much higher than that on the level of sentences. From the results, we can come to a conclusion that training the listening skill with words in mid-tonality and low-tonality based on OFH might give a great positive effect in improving listening ability for Korean learners of English.

• PNF and Movement
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• v.18 no.2
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• pp.173-182
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• 2020

Purpose: The purpose of the study was to investigate the effects of visual feedback exercise (VFE), sandal exercise (SE), and thera-band exercise (TE) on people with functional ankle instability. Methods: The 45 study participants were divided into three groups of 15. In the VFE group, participants performed short-foot exercises using visual feedback; the SE group performed sandal exercises, and the TE group performed thera-band exercises. Over a period of 8 consecutive weeks, the experimental groups exercised for 15 minutes per session, four times per week. Balance was measured using the Biodex Balance System for dynamic balance ability (overall balance index [OBI], mediolateral balance index [MBI], and anterioposterior balance index [ABI]). Vibration threshold sense (VTS) was assessed using a vibratory sensory analyzer. Ankle muscular strength was measured using the Biodex 4 Pro. The main outcome measures were assessed at baseline and after 8 weeks of training. Results: Significant improvements in dynamic balance were noted in all three groups (p < 0.05). Significant improvements in VTS and muscular strength were also noted in the VFE and TE groups but not in the SE group (p < 0.05). Conclusion: Appropriate environmental and situational mediation may be of great clinical significance for patients suffering from chronic ankle instability. It is hoped that the findings will inform a program for prevention of ankle instability.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.36-38
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• 2017

The advent of the era of data age and advances inartificial intelligence technology has led to innovations in various business areas. In particular, many attempts have been made to improve the stability of the marine accident, which has not previously been applied by a data-drive approach. Most of the marine accidents happen at a time when the vessel isapproaching a port and preparing for berthing. Although the cause of the accident has many factors, it is often caused by the difficulties of communication between the ship navigator and the control center. In particular, communication in English makes difficulties for navigators, not English astheir first language. To do this, proper English conversation education forsailors is very important. In order to support the issue, this study presents data and framework for the development of a chatbot for ship safety education.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.1
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• pp.31-38
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• 2020

The characteristics of ship traffic routes and the long term fluctuation in marine traf ic volume of the incoming and outgoing routes of the Yeosu Gwangyang Port were analyzed using vessel traffic data from the past 22 years and a real-time vessel traffic volume survey performed for 72 hours per year, for three years, between 2015 and 2017. As of 2017, the number of vessels passing through Yeosu Gwangyang Port was about 66,000 and the total tonnage of these ships was about 804,564 thousand tons, which is a 400 % increase from the 189,906 thousand tons shipped in 1996. Specifically, the dangerous cargo volume was 140,000 thousand tons, which is a 250 % increase compared to 1996. According to the real-time vessel traffic volume survey, the average daily number of vessels was 357, and traf ic route utilization rates were 28.1 % in the Nakpo sea area, 43.8 % in the specified sea area, and the coastal area traf ic route, Dolsan coastal area, and Kumhodo sea area showed the same rate of 6.8 %. Many routes meet in the Nakpo sea area and, parallel and cross passing were frequent. Many small work vessels entered the specific sea area from the neighboring coastal area traffic route and frequently intersected the path of larger vessels. The anchorage waiting rate for cargo ships was about 24 %, and the nightly passing rate for dangerous cargo ships such as chemical vessels and tankers was about 20 %. Although the vessel traffic volume of Yeosu Gwangyang Port increases every year, the vessel traffic routes remain the same. Therefore, the risk of accidents is constantly increasing. The route conditions must be improved by dredging and expanding the available routes to reduce the high risk of ship accidents due to overlapping routes, by removing reefs, and by reinforcing navigational aids. In addition, the entry and exit time for dangerous cargo ships at high-risk ports must be strictly regulated. Advancements in the VTS system can help to actively manage the traffic of small vessels using the coastal area traffic route.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.375-381
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• 2013

To assess the risk of marine traffic environments, with high confidential level, the risk factors comprising it should be identified and the risk acceptance criteria should be also provided. Furthermore, the relative importance of each risk factor(the weight of each risk factor on total risk) should be analyzed because the risk is expressed as the sum of risk factors comprising it. The twenty kinds of risk factors and its assessment criteria were suggested for the domestic marine traffic environments by an examination of the existing risk assessment models on the previous studies. The relative importance of each risk factor was also analyzed through the questionnaire using analytic hierarchy process by the marine traffic experts on the same studies. Based on these previous studies, the risk was evaluated at the port of Mokpo and its approaches on this study. The port of Mokpo and its approaches were divided into four sectors for the comparative evaluation, the result of the comparative evaluation on four sectors showed that the risk of the Jeongdeung-hae passage is the highest due to higher risk level of some risk factors(water movements, complexities, tug boats, pilotage, VTS) than the other sectors. The result of this evaluation is in accord with the analysis results of the other studies using various qualitative or quantitative risk analysis methods at the same sea areas.