• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.164-170
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• 2013

With the introduction of increasingly large-sized ships, the conditions of main domestic port facilities remain the same as in the past. So, there is high probability that marine traffic congestion can occur at the certain ship's routes. The standard ship's length used to assess the marine traffic congestion of domestic trade port is 70 meters. It has been in use for the last 30 years, so, its usefulness is highly recommended for review. This study deeply analyzes the tendency of ship's dimensional changes according to recent enlargement of ship's size by utilizing the particulars of 60,000 ships saved in domestic Port-MIS database and suggests the standard ship's length by figuring out the correlation between length of ship and gross tonnage. In addition, the basis of statistical data on the ship's tonnage in domestic trade over the last five years suggests the standard ship's length by deriving the reference point of cumulative incidences that occupy more than over 50 %, except for small vessels. It is necessary to consider the characteristic of each domestic trade port before the actual application of suggested standard ship's length.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.5
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• pp.1071-1077
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• 2010

The six-port phase correlator using lumped elements was designed and fabricated in this paper, also the receiving performance of L-band direct conversion receiver using lumped six-port phase correlator element was analyzed. The proposed L-band lumped six-port phase correlator element was composed of a resistive power divider and the twist-wire coaxial cables. The proposed lumped six-port structure provides the small-sized configuration and wide-band characteristics. The performance of the L-band lumped direct conversion receiver structure was measured under the conditions of 1.69 GHz frequency for LO-CW signal and RF-QPSK signal, which are input signals for the lumped six-port phase correlator element. The direct conversion receiving structure using the proposed lumped six-port phase correlator element can recovered the good digital I/Q signal.

• Journal of Korea Port Economic Association
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• v.34 no.3
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• pp.53-74
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• 2018

The purpose of this study is to give a guiding implications to strengthen the competitiveness of port policy in Philippines, considering the inefficiencies in the port infrastructures and management systems in the country, despite its average economic growth of 5-6% and subsequent increment in passenger and trading volumes. These growth figures imply a compelling need for a systemic development plan and impellent actions. This study used the analytic hierarchy process for conducting a port competitiveness analysis and the data on deterrent factors were collected through literature and internal government documents including on-site interviews of the parties involved. The implications of the analysis led the study to conclude the need for adopting an enhanced centralized management, a separate investment and management for ports, a grade classification of nationwide small-, medium, and large-sized ports, efficient incoming systems for port dues, and an advanced mode of financing and investment inducement, among others.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.73-78
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• 2004

For the preliminary stages of ship design it is necessary to develop a basic design, which specifies the main particulars of the vessel. based on the requirements given by the owner. An efficient design enables the shipyard to make a rough estimate of the construction costs and to put forward a favourable quote during the call for tenders. The parametric determination of the main particulars of the vessel involves the application of empirical formulae. These formulae have been created after detailed tests and research by maritime research institutions and researchers had been carried out. Here, the design of a medium sized Bulk Carrier (26000t dwt) with a service speed of 17 knots for carrying rice and rock phosphate has been illustrated. Medium sized Bulk Carriers (25,000t dwt - 50,000t dwt) are in steady demand among small shipping companies. They have a size advantage, in that port size restrictions do not affect their design tremendously. Nevertheless, structurally. they are one of the most difficult to build. During design, the rules of the maritime regulatory bodies were strictly adhered to.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.798-807
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• 2021

In the era of the fourth industrial revolution, Maritime Autonomous Surface Ship(MASS) are expected to emerge in the shipping industry. There has been much active research on collision avoidance systems regarding MASSs, but most of it has focused on merchant ships. A study of collision avoidance systems in fishing vessels is also essential, because Maritime Autonomous Surface Ships will encounter all type of vessels. In this study, the minimum passage distance between small-medium-sized fishing vessels and other vessels was investigated for the Ship's domain analysis. Based on the AIS data of Busan port and the adjacent area, the separation distances of fishing vessels were analyzed. The results indicated that as the speed of fishing vessels increased, the distance increased from 4L to 8L, and as length of the fishing vessels increased, the distance decreased from 10L to 6L. It is believed that the results of this study can be applied in the future to collision avoidance models for MASSs that reflect the domain of fishing vessels.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.29-36
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• 1983

The treatment of tumors along curved surfaces with stationary electron beams using cone collimation may lead to non-uniform dose distributions due to a varying air gap between the cone surface and patient. For large tumors, more than one port may have to be used in irradiation of the chest wall, often leading to regions of high or low dose at the junction of the adjacent ports. Electron-beam arc therapy may elimination many of these fixed port problems. When treating breast tumors with electrons, the energy of the internal mammary port is usually higher than that of the chest wall port. Bolus is used to increase the skin dose or limit the range of the electrons. We invertiaged the effect of various arc beam parameters in the isodose distributions, and combined into a single arc port for adjacent fixed ports of different electron beam eneries. The higher fixed port energy would be used as the arc beam energy while the beam penetration in the lower energy region would be controlled by a proper thickness of bolus. We obtained the results of following: 1. It is more uniform dose distribution of electron to use rotation than stationary irradiation. 2. Increasing isocenter depth on arc irradiation, increased depth of maximum dose, reduction in surface dose and an increasing penetration of the linear portion of the curve. 3. The deeper penetration of the depth dose curve and higher X-ray background for the smaller field sized. 4. If the isocenter depth increase, the field effect is small. 5. The decreasing arc beam penetration with decreasing isocenter depth and the isocenter depth effect appears at a greater depth as the energy increases. 6. The addition of bolus produces a shift in the penetration that is the same for all depths leaving the shape of the curves unchanged. 7. Lead strips 5 mm thick were placed at both ends of the arc to produce a rapid dose drop-off.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.529-538
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• 2018

The port industry is an important national industry which significantly affects Korea's imports and exports which are centered on economic structure. For instance, the Port of Busan, which handles 75% of domestic container freight volume, is expected to become increasingly critical for container liner routes. For this reason, there have been continued efforts to expand freight service to attract international freight volume. This study analyzes the structural characteristics of the port network connected to the Port of Busan by analyzing the pattern of the container liner route from 2012 to 2016 by using social network analysis. According to the Port of Busan's liner route network, the port with the highest degree of centrality, closeness centrality, and betweenness centrality was found to be the Port of Singapore. The comparison of Busan's annual container handling rank by countries and the port center network analysis of Port of Busan rank was found to be different. As a result, it was established that China's East Port, which occupies a high percentage of the volume of cargo handled by Port of Busan, is not a hub port of Busan when viewed on the Busan's container terminal liner network. In addition, even if the number of Port of Busan container liner service increases, it is estimated that the vessels to be added to the fleet will be limited to small to medium sized, or that Busan port has characteristic of a feeder port for the Port of Singapore, according to the network.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.518-521
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• 2016

Korea is surrounded on three sides by the sea, through the maritime transportation accounts for close to 90% share in the total cargo volume. In addition, there are amount of small and medium-sized fishing vessels registered. These days, a number of maritime accidents caused many casualties and having an adverse effect on the marine environment. Therefore, there is a need for a maritime traffic control has been increasing. Information about the ship is divided into AIS information for VTS, Port Management Information System (Port-MIS) operated by the Port and vessels pass (VPASS) that are installed on fishing. However, there is a problem that is not achieved the information exchanged between each other. That is, information on the vessel are stored in diverse inefficient in the management, operation and utilization. This paper discusses the ways to efficiently manage and integrate vessels information for VTS, and proposes the method for implementation and application.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.97-101
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• 2004

In this paper, we study the fishery detection system for protection of an aquamlture farm. The FDS(fishery detection system) will be recognize a robbing vessel with real time and variance the position of aquaculture farm. We try to develop the F-AIS(Fishery Automatic Identification System) which am be detect approaching object to aquaculture farm and distinguish our fishing boot from thief vessel. The F-AIS with low price and wideband responsibility am be adopt to the FDS, i. e. the identification for a small-sized fishing boots.

• Journal of Navigation and Port Research
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• v.27 no.1
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• pp.15-30
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• 2003

The shipboard working environment of coastal patrol ship is very inferior to the ground working environment and it cause the avoidance of shipboard working and the aging of crew. Especially the noise in ship cause on occupational shipboard working hardness of hearing. Hence to reduce the shipboard working fatigue is necessary by the security of the comfortable shipboard working environment and residence environment. in this paper, firstly we evaluate the shipboard working by suing the measurement results of the evaluation results of the shipboard working environment.