• Journal of Fisheries and Marine Sciences Education
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• v.21 no.1
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• pp.59-67
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• 2009

It is necessary for navigator to understand sufficiently maneuverabilities based on experiences and the data which were gotten from several tests of the ship when he maneuver his vessel. By the way most navigators used to rely on his experiences or feelings only maneuvering ship. But when he encounters situations he did not experience before he may be in difficulties. So navigator must get both experiences and data based on experimental results. In this paper author performs several tests such as turning test, Zig-zag test and spiral test to provide informations of maneuverabilities for navigators. The obtained results are as follows: There occurs almost no difference in size of the turning circle by the changes of ship's speeds. The scale of the turning circle was decreased exponentially when the rudder angle was increased. The maneuverabilities is better turning to starboard side than to port side. Maneuverabilities are more effective when the rudder is used to small angle than to large angle. As a result of spiral test course stability was comparatively seemed to be good.

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.144-150
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• 2005

The size of ship is being larger than the past in the shipping industry thanks to the increased quantity of goods transported by ship. Therefore, HHIC (Hanjin Heavy industries & Construction co., LTD) invented innovative construction method, so called 'DAM', to build a ship which is longer than the length of the HHIC's dry dock. On Erection at the sea by the application of DAM Method, Squeezing & Detachment of A/F film may occur as a result of the wave and the constriction between A/F film pre-applied on the side shell and DAM's Rubber Packing. Thus, the test for finding the minimum curing time of A/F film was performed to protect Squeezing & Detachment of A/F film on the hull. To verify the soundness of paint and to find the optimum condition during the erection period of the DAM, laboratory test was carried out under no immersion condition through the application of various coatings on the Rubber Packing. And two methods were selected from the results of laboratory test for actual MOCK-UP Test. In addition, the test for the film profile per temperature of silicone A/F coat and the film Squeezing was performed.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.383-388
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• 2003

.Ports are usually designed as a dead en port. With an increasing tendency of ship size, the problems such as maneuvering difficulty, turning basin, tugboat fee, etc. are getting to be pointed out. For solving such problem, the conversion of the idea fro dead end port to one-way through port is encourage. To examine the advantage of one-way through port, a quantitative and systematic analyzing procedure is needed. For this, this paper evaluated the preference on the three way of departture using the fuzzy measure and integral model.

• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.361-368
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• 2007

The storage space requirement is a very important decision variable which determines the storage capacity of a container terminal. Generally, the storage space requirement is dependent upon such factors as ship headway, allowable dwell time of containers, loading/winding time per ship, and so on. Until now, the storage space requirement is estimated under the assumption that the factors are deterministic in several studies. However, this study proposes how to estimate a storage space requirement satisfying the required service level under the assumption that a containership's load size is probabilistic. Numerical experiments, which use a simulation show that the proposed method can estimate more adequately the storage space requirement than other methods under a probabilistic environment.

• Journal of the Korean Institute of Navigation
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• v.15 no.1
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• pp.12-47
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• 1991

This work aims to introduce the concept of microcomputer aided port design simulation methodology including the analysis of the mathematical models to be implemented and apply it to the Third Stage Busan Port Development Project. In the Busan case study, the size of the proposed turning basin of the new terminal, together with the operational strategies of berthing and unberthing, was examined, In addition, the safety on ship's entry and exit through the projected new breakwaters was ascertained. From the application of simulation to the Busan project, it was found that the proposed dredging area was not sufficiently wide enough for the modelled container ship to perform A time unberthing (in which the ship turns to port as she manoeuvres away from N.1. Berth with the assistance of tugs), especially in a strong easterly wind. It is therefore, recommended that Busan pilots should be advised to sue B type unberthing strategy, in which the ship goes astern from no.1 berth tot he turning area in front of No.2 berth(where the ship turns 180 degrees clockwise), especially when the wind is very strong, It is also recommended that a sea buoy be placed outside the new breakwaters, as this was found to improve the safety of ship manoeuvres through the breakwaters significantly . Another recommendation is that the Korean hydrodynamic Office carry out a detailed survey of the currents in the water area near the new breakwaters once they have been constructed. In addition, it is to be recommended that a current meter be placed at the recommended sea buoy to improve the safety of ship manoeuvres which could otherwise be jeopardised by eeroneos current information.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.2 s.140
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• pp.129-135
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• 2005

At present, fatigue design of welded structures is primarily based on a nominal stress or hot spot stress approach with a series of classified weld S-N curves. Although well accepted by major industries, the nominal stress based fatigue design approach is cumbersome in terms of securing a series of S-N curves corresponding to each class of joint types and loading modes. The hot spot stress based fatigue design has a difficulty of finding a proper stress through the global model, the midium size model, and the detail model of ship structure. Also, it is difficult to link proper displacements within three different mesh size models. Recently, the structural stress is proposed as a mesh-size insensitive structural stress definition that gives a stress state at weld toe with relatively large mesh size. However, this method requires an experimental validation in obtaining the fatigue strength of weldments. Therefore, in this study, a series of experiment is performed for various sizes of weldments.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.139-145
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• 2002

The flow zone through propeller jets are used in evaluating the environmental and constructional effects of navigation on the waterway. It relies on the characteristics of ships and water depth. A numerical model using the momentum theory of the propeller and Shield's diagram was developed in a restricted waterway. Equations for discharge are presented based on thrust coefficients and propeller speed and are the most accurate means of defining discharge. Approximate methods for discharge are developed based on applied ship's power. Equations for discharge are as a function of applied power, propeller diameter, and ship speed. Water depth of the waterway and draft of the shop are also necessary for the calculation of the grain size of the initial motion. The velocity distribution of discharge from the propeller was simulated by the Gaussian normal distribution function. The shear velocity and shear stress were from the Sternberg's formula. Case studies to show the influence of significant factors on sediment movement induced by the ship's propeller at the channel bottom are presented.

• Journal of Navigation and Port Research
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• v.31 no.6
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• pp.447-454
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• 2007

To assess the port development and maritime traffic environment, the future traffic volume has been estimated using the number of inbound and outbound vessel for a specific port. The estimation of future traffic volume should be considered as an important factor to establish the degree of fairway congestion, the determination of fairway width and the operational role. Until now, the number of in and out vessel for the port has been only estimated mainly, but the type and size of inbound and outbound ships are different depending on the port's characteristics. So, it is difficult to estimate the future traffic volume using the change of only one item. This paper calculates the future traffic volume using the marine traffic characteristic factors as the number of coastal ship and ocean-going ship, the size of ship and the change of cargo volume per a ship etc. And it compared with the results of Artificial Neural Network(ANN) for accurate identification of nonlinear system.

• Journal of Korea Port Economic Association
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• v.19 no.1
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• pp.23-41
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• 2003

The purpose of this paper is to analyze the gravitation of ship's cargo tons of arriving and leaving port of Busan based on the gravity model empirically and experimentally and to suggest possible ways to expand the trade quantities(cargo tons) by identifying important factors determining the port of Busan's bilateral trade flows with foreign countries by using the 1995, and 2001 data. In this paper, new independent variables, such as land, populations, and the APEC and ASEAN memberships, and new dependent variable, such as the ship's cargo tons of arrival and leaving port of Busan were used for expanding the previous studies. Empirical analysis found that the port of Busan tends to trade more with countries in close proximity and the large size of economies. The fact that the port of Busan's trades more with APEC countries than with non-APEC countries is a clear empirical evidence of the growing importance of the regional trade agreement and strategic alliance with the ports of these member countries. The main policy implication based on the findings of this study is that GDP, distance, adjacency, and APEC membership which were the affecting variables to the bilateral trade with the port of Busan should be closely investigated for enhancing the trade quantities with those foreign countries.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.653-660
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• 2005

There has been only a deep water route for deep draft vessels without any other routeing system in Yosu Bay despite of the rapid change in ship's size and increase in the traffic volume since the specified area for traffic safety was established in 1988. In this work, we suggest several solutions to secure ship's safety and to eliminate dangerous factors which exists in present ship traffic system Consequently, this work is to propose improved marine traffic system in future.