• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.1
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• pp.101-106
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• 2012

Ship handling simulator is a virtual ship navigating system with three dimensional screen system and simulation programs. FTS simulation can produce theoretically infinite experiment tests without time constraint, but which results in collecting determinstic observations. RTS simulation can collect statistical observations but has disadvantage of spending at least 30 minutes for a single experiment. The previous studies suggested that the number of experiment conditions to be tested could be reduced to obtain random data with RTS simulation by focusing on highly difficult experiment condition for ship handling. It has the limitation of not estimating the distribution of ship handling difficulty for the route. In this paper, similarity and clustering analysis are suggested for reduction methodology of experiment conditions. Similarity of experiment conditions are measured as follows: euclidean distance of ship handling difficulty index and correlation matrix of distance differences from the designed route. Clustering analysis and multi-dimensional scaling are applied to classify experiment conditions with measured similarity into reducing the number of RTS simulation conditions. An empirical result on Dangin harbor is shown and discussed.

• Journal of Navigation and Port Research
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• v.36 no.9
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• pp.715-720
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• 2012

This paper is to introduce the development of a LCD monitor-based pilots' ship handling simulator installed in the office of Korea Maritime Pilots Association. This simulator is composed of hardware which includes working server array, operation PC, monitor array, rudder, thruster and telegraph peripheral devices, and software which includes ship mathematical model software, ship conning software, image supporting software and so on. In this simulator, MMG mathematical model is used to create thirteen(13) ship models, which are based on sea trial data & pilots' opinion. According to requirements of pilots, virtual scenes of different port areas are built, and some required additional functions are also developed. By using this simulator, pilots can fulfill all kinds of training exercises, design of channel approaching ports, traffic safety analysis, prevention of accident research and other tasks, so as to grasp the characteristics of different ships, and accumulate experience for piloting.

• Journal of the Korean Society of Marine Environment & Safety
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• v.7 no.3
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• pp.85-92
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• 2001

Ship handling simulator has much merit to provide trainees with real-like circumstances in doing virtual education and training. To improve the quality of the education, it should be included both the mathematical model which can explain complicated ship's manoeuvrability and graphic tools for 3D images which can embody the visual scenes of reality on screen. This paper is focused on how to construct the marine environment DB(data Base) using S-57 data of ENC(Electronic Navigational Chart).

• Journal of Ship and Ocean Technology
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• v.6 no.3
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• pp.26-36
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• 2002

Yaw-checking and course-keeping ability in IMO's ship rnanoeuvrability standards is reviewed from the viewpoint of safe navigation. Three kinds of virtual series-ships, which have different course instability, are taken as test models. The numerical simulation on Z-test is carried out in order to examine the correlation between known manoeuvrability in spiral characteristics and various kinds of overshoot angle. Then simulator experiments are executed with series-ships in a curved, narrow waterway by five pilots in order to examine the correlation between known manoeuvrability and degree of manoeuvring difficulty. IMO criteria for yaw-checking and course-keeping ability are discussed and new criteria are proposed.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.369-376
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• 2019

Ship hydrodynamics in the confined waterways is challenging. When a ship is maneuvering in confined waterways, the hydrodynamic behavior may vary significantly because of the hydrodynamic interaction between the bottom of the ship hull and the seabed, or so-called shallow water effects. Thus, an accurate prediction of shallow water and bank effects is essential to minimizing the risk of the collision and the grounding of the ships. The hydrodynamic derivatives measured by the virtual captive model test provide a path to predicting the change in ship maneuverability. This paper presents a numerical simulation of captive model tests to predict the maneuverability of a ship in confined waterways. Also, straight and zig-zag simulation were conducted to predict the trajectory of a ship maneuvering in confined waterways. The results showed that the asymmetric flow around a ship induced by vicinity of banks causes pressure differences between the port and starboard sides and the trajectory of a ship maneuvering in confined waterways.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.4
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• pp.86-93
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• 2011

The ship movement implies current position, wave, wind, and its other factors. We need to know exactly the location and the shape of the ship and control its motion because of these effects. In order to control the small ship according to the movement of the large ship, the position and shape of the ship should be given first. In this paper we propose the method with which we know the current status of the ship without dynamic equations of the ship. There are several methods to track the system such as optical, radio frequency, radar, camera, and infrared light. We propose the movement of the ship using the GPS absolute axis. But, the genuine error by the GPS itself and the movement of the ship cause the result of the GPS of not being accurate. This paper reduces the error of the location and the shape of the ship and gives the exact values of the ship movements even if the GPS implies some error itself.

• International Journal of Naval Architecture and Ocean Engineering
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• v.3 no.3
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• pp.181-192
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• 2011

Recently, the speed of change related with enterprise management is getting faster than ever owing to the competition among companies, technique diffusion, shortening of product lifecycle, excessive supply of market. For the example, the compliance condition (such as delivery date, product quality, etc.) from the ship owner is getting complicated and the needs for the new product such as FPSO, FSRU are coming to fore. This paradigm shift emphasize the rapid response rather than the competitive price, flexibility and agility rather than effective and optimal perspective for the domestic shipbuilding company. So, domestic shipbuilding companies have to secure agile and flexible ship production environment that could respond change of market and requirements of customers in order to continue a competitive edge in the world market. In this paper, I'm going to define a standard shipbuilding production management system by investigating the environment of domestic major shipbuilding companies. Also, I'm going to propose a unified ship production management and system for the operation of unified management through detail analysis of the activities and the data flow of ship production management. And, the system functions for the strategic approach of ship production management are investigated through the business administration tools such as performance pyramid, VDT and BSC. Lastly, the research of applying strategic KPI to the digital shipyard as virtual execution platform is conducted.

• Journal of the Ergonomics Society of Korea
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• v.32 no.4
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• pp.333-340
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• 2013

Objective: The aim of this study is to provide a current knowledge of the multiple issues regarding motion effects on crew performance. Background: The motions of the ship may create motion sickness, nausea and vomit. Also, these motions also disturb the balance of crew members, increase the energy expenditure of crew for shipboard work, and result in increased levels of injury and fatigue. However, the motion effects of the ship on crew performance has not been thoroughly investigated. Method: Participants(N=10) were engaged in an experiment in 2 experimental environments(training ship and ship handling simulator) and 2 navigational conditions(day and night). The COP(Center of Pressure) data were recorded as an objective measure of postural balance control and the SSQ(Simulator Sickness Questionnaire) was used as a subjective measure of sickness. Results: The results showed that COP has a no significant difference based on experimental environments, but significant effect on SSQ. Conclusion: During the virtual simulator navigation, subjects showed significant SSQ level changes, which included decreased SSQ data. But, there is no significant difference of COP between training ship and ship handling simulator. Application: The results of this study could be applied to the next generation of ship design to decrease effect of motion at sea and to increase performance of ship crew.

• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.77-81
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• 2009

The radar cross section (RCS) of a warship is one of the most important design features in terms of her survivability in hostile environments. Ocean waves continuously changes the attitude of an objective warship to hostile radar and distorts the RCS as a result. This paper presents a dynamic RCS analysis technique and procedure that considers temporal ship motion. First, data sets are prepared for ship motions in 6 degrees of freedom, which are numerically simulated for an objective warship via frequency to time domain conversion with response amplitude operators and specified ocean wave spectra. Second, a series of RCS analysis models are transformed geometrically by referring to ship motion data sets. Finally, temporal RCS analyses are carried out with the RCS simulation code, SYSCOS. As an example, RCS analysis results are given for a virtual warship, which show that ship motions temporally change RCS values and cause RCS reduction compared with static value in terms of mean values.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.3
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• pp.274-280
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• 2018

This paper deals with the calculation of vulnerable areas of critical components required for the assessment of naval ship's vulnerability. Taking into account the effectiveness of threatening weapons, the probability density function of damage was used to assess vulnerable areas or vulnerabilities of critical components. It is shown that the vulnerable area of critical component can be simply computed from the damage function. Considering the weapon effectiveness of fragmentation and explosion on the target, both Carleton Damage Function and Rectangular Cookie Cutter Function representing the probability of damage are applied to the vulnerable area assessment. Carleton damage function is utilized to describe the weapon-target interaction in the vulnerability analyses. A problem of blast effect against an assumed naval ship is chosen as a case study. Vulnerability is evaluated by applying the suggested method to the equipments arranged in the engine room of the virtual ship.