• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.415-421
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• 2018

The Republic of Korea has a more rapidly aging society than any other country in the world. In order to prepare for the attendant challenges, this research provides basic data for policies related to aging ship officers, analyzing the relationship between elderly ship officers and marine accidents. The data used here spans 11 years, from 2006 to 2016, and the survey and regression analysis were conducted only on ship officers, excluding crew. As a result of this research, first, it was found that the number of employed ship officers older than 60 has increased 2.7 times over the past 11 years and the range of this increase was larger than for other age categories. Second, the number of elderly ship officers disciplined for marine accidents increased by around 2.6 times. Third, elderly ship officers had around 1.5 times the rate of marine accidents compared to non-elderly ship officers. Fourth, as a result of conducting regression analysis between the number of employed elderly ship officers and the number of officers disciplined, the degree of explanatory power of elderly ship officers for disciplined officials was 75.1%. Since our society will age quickly, policies such as license renewal education for elderly ship officers and regulation enforcing the quality of renewal will be needed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.2 s.29
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• pp.133-140
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• 2007

Since early times, captain have been sailing to select the optimum route considering the weather, ship loading status condition and operational scheduling empirically. However, it is rare to find digitalized onboard route support system whereas weather facsimile or wave and swell chart are utilized for the officer, based on captain's experience. In this paper, optimal route safety assessment system which is composed of voyage efficiency and safety component is introduced. Optimum route minimizea ETA(estimated time of arrival) and fuel consumption that shipping company and captain are requiring to evaluate for efficient voyage considering speed loss and power increase based on wave added resistance of ship. In the view point of safety, seakeeping prediction is performed based on 3 dimensional panel method. Finally, It is assistance measure for ship's optimum navigation route safety planning & assessment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.39-45
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• 2006

Based on the previous studies on alcohol effects on human behaviour and performance in transportation system such as air-plane and car driving, the alcohol exposure before and on watch of a ship has a great influence on subsequent behaviour. In this paper, to examine the drinking status of officers on board multiple choice questionnaires are circularized under instruction and surveyed for 118 officers. According to the results of the questionnaire survey on alcohol dependency (Alcoholism) that was invented by WHO, over 27 % of those surveyed represented alcohol abuse symptoms. In addition to that, the existing state and awareness for on-board-drinking was summarized to make a scenario of drink-operation with a ship handling simulator to investigate the effect of alcohol (0.08 g% blood alcohol concentrations) on ship operational performance. A main effect for alcohol was found indicating that ship operational performance was comparatively impaired by this alcohol relative to performance in the non-alcohol condition The results of this research can be applied to minimize marine accidents as basic data.

• Journal of the Korea Society for Simulation
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• v.19 no.3
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• pp.127-135
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• 2010

Modern marine navigation requires officers on the bridge to monitor a torrent of data on both the insides and outsides of the ship from numerous useful devices. But despite these tools, navigators can still find it difficult to make a safe decision for two reasons: one is that too much data if provided too quickly tends to cause fatigue and overwhelm the officer, and the other is that any inconsistency across data from several different types of devices can lead to confusion. Indeed, the fact remains that the many marine accidents can be attributed to human error, and hence there is a strong need for decision-support tools for marine navigation. One technique of providing decision support is through the use of simulation to evaluate or predict system dynamics over time using an accurate model. This paper, as a simulation method for risk prediction for a navigation safety information system of ship, suggests a navigation prediction simulation system using various knowledge bases and discrete event simulation methodology, and supports the validity of the system through the examples of components in a restricted navigation situation scenario.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.253-259
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• 2012

The projection on the demand for seafarers is seen to continue to rise in consonance with the world's fleet increasing tonnage. It is also expected that recurring officer shortages is paramount when global markets bounce off from the economic downturn it experienced for the last few years. In BIMCO/ISF(The Baltic and International Maritime Conference/International Shipping Federation) report for 2010, a continuous effort to produce competent seafarers should be adapted and as much as possible, reduce the wastage in the industry to address the looming scenario. The Republic of Korea, an OECD member, is a powerhouse in shipbuilding industry and has also had continued to show also an expanding trend in its fleet. On the other hand, the Philippines is still acknowledged as the main source of manpower for ocean-trading vessels. In this paper, a statistical comparison of maritime graduates' career path between the two countries is presented. In conclusion, it is suggested that a mutual co-operation between the Republic of Korea and the Philippines can be established with focusing on international maritime education and training collaboration.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.98-107
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• 2016

The purpose of this study is for Human error prevention to acquire Collision Risk Perception Index (CRPI) sensed by the Officer Of the Watch (OOW) when the approaching distances are reduced in six types of ship encountering situations (Head on, $045^{\circ}$, $090^{\circ}$, $135^{\circ}$, Overtaking, Overtaken) between own ship and a target ship and then to predict CRPI fitting coefficients with polynomials in the curve-fitting process. CRPI acquisition experiments are carried out on two coast-guard ships and with the total of 30 crew members. Analysing results shows that CRPI data have goodness of fit to the six types of encountering situation. Futhermore, the One-Way ANOVA results show that CRPI has a negative affect to the OOW's age, career and license grade as the approaching distances is reduced. The availability of CRPI curve fitting with 3 degrees of polynomial was testified through the RMSE as 1.19 to Head on, 0.87 to $045^{\circ}$, 0.81 to $090^{\circ}$, 0.71 to $135^{\circ}$, 1.29 to Overtaking and 0.87 to Overtaken.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.4
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• pp.405-412
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• 2019

SOLAS requires that ECDIS be installed on ships of more than 500 gross tonnage engaged in international navigation until the first inspection arriving after July 1, 2018. Several accidents related to the use of ECDIS have occurred with its installation as a new major navigation instrument. The 12 incident reports issued by MAIB, BSU, BEAmer, DMAIB, and DSB were analyzed, and the cause of accident was determined to be related to the operation of the navigator and the ECDIS system. The text was analyzed using the R-program to quantitatively analyze words related to the cause of the accident. We used text mining techniques such as Wordcloud, Wordnetwork and Wordweight to represent the importance of words according to their frequency of derivation. Wordcloud uses the N-gram model as a way of expressing the frequency of used words in cloud form. As a result of the uni-gram analysis of the N-gram model, ECDIS words were obtained the most, and the bi-gram analysis results showed that the word "Safety Contour" was used most frequently. Based on the bi-gram analysis, the causative words are classified into the officer and the ECDIS system, and the related words are represented by Wordnetwork. Finally, the related words with the of icer and the ECDIS system were composed of word corpus, and Wordweight was applied to analyze the change in corpus frequency by year. As a result of analyzing the tendency of corpus variation with the trend line graph, more recently, the corpus of the officer has decreased, and conversely, the corpus of the ECDIS system is gradually increasing.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.47-52
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• 2021

Recently, the share of wind power in energy markets has sharply increased with the active development of renewable energy internationally. In particular, large-scale wind farms are being developed far from the coast to make use of abundant wind resources and to reduce noise pollution. In addition to the electromagnetic interference (EMI) caused by offshore wind farms to coastal or air surveillance radars, it is necessary to investigate the EMI on global maritime distress and safety system (GMDSS) communications between ship and coastal stations. For this purpose, this study investigates whether the transmitted field of MF/HF band from a ship would be subject to interference or attenuation below the threshold at a coastal receiver. First, using geographic information system digital maps and 3D CAD models of wind turbines, the area of interest is electromagnetically modeled with patch models. Although high frequency analysis methods like Physical Optics are appropriate to analyze wide areas compared to its wavelength, the high frequency analysis method is first verified with an accurate low frequency analysis method by simplifying the surrounding area and turbines. As a result, the received wave power is almost the same regardless of whether the wind farms are located between ships and coastal stations. From this result, although wind turbines are large structures, the size is only a few wavelengths, so it does not interfere with the electric field of MF/HF distress communications.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.2
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• pp.307-313
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• 2022

As the development of renewable energy expands internationally to cope with global warming and climate change, the share of wind power generation has been gradually increasing. Although wind farms can produce electric power for 24 h a day compared to solar power plants, Their interfere with the operation of nearby radars or communication equipment must be analyzed because large-scale wind power turbines are installed. This study analyzed whether a land radio station can receive sufficient signals when a ship sailing outside the offshore wind farm transmits distress signals on the VHF band. Based on the geographic information system digital map around the target area, wind turbine CAD model, and wind farm layout, the area of interest and wind farm were modeled to enable numerical analysis. Among the high frequency analysis techniques suitable for radio wave analysis in a wide area, a dedicated program applying physical optics (PO) and shooting and bouncing ray (SBR) techniques were used. Consequently, the land radio station could receive the electromagnetic field above the threshold of the VHF receiver when a ship outside the offshore wind farm transmitted a distress communication signal. When the line of sight between the ships and the land station are completely blocked, the strength of the received field decreases, but it is still above the threshold. Hence, although a wind farm is a huge complex, a land station can receive the electromagnetic field from the ship's VHF transmitter because the wave length of the VHF band is sufficiently long to have effects such as diffraction or reflection.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.937-945
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• 2022

Maritime autonomous surface ships (MASS) have a high degree of autonomy and operate autonomously along a planned route. However, when necessary, the shore remote control center(SRCC) can directly intervene in ship operations. In this paper, the operation concept of the simulator system, which can be used to educate and train shore remote control officers, responsible for monitoring the operation of autonomous ships on land and remotely controlling them in case of an emergency, is reviewed. The required functions of the simulator system that enables the operation concept are also reviewed. The major parts of the SRCC simulator system are the monitoring station and control station, which simulate the functions of monitoring the operation status of multiple MASS and the functions of the remote operation of MASS in the case of emergency, respectively. Various units to simulate the operation of MASS and traf ic ships and various objects around the MASS are included in the simulator system. The instructor operation station is the central part of the simulator system that integrates and controls the unit systems. Functionally, as conditions under which SRCC is allowed to remotely intervene in the operation of MASS, the emergency situation for remote control (ESRC) has been defined. Moreover, the required functions to cope with these ESRC conditions have been included in the simulator system requirements.