• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.17-22
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• 2005

This paper presents a new adaptive autopilot for ships based on the Adaptive Neural Networks. The proposed adaptive autopilot is designed with some modifications and improvements from the previous studies on Adaptive Neural Networks by Adaptive Interaction (ANNAI) theory to perform course-keeping, turning and track-keeping control. A strategy for automatic selection c! the neural network controller parameters is introduced to improve the adaptation ability and the robustness of new ANNAI autopilot. In Part II of the paper, to show the effectiveness and feasibility of the proposed ANNAI autopilot, computer simulations of course-keeping and track-keeping tasks with and without the effects of measurement noise and external disturbances are presented.

• Journal of Navigation and Port Research
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• v.29 no.9
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• pp.771-776
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• 2005

This paper presents a new adaptive autopilot for ships based on the Adaptive Neural Networks. The proposed adaptive autopilot is designed with some modifications and improvements from the previous studies on Adaptive Neural Networks by Adaptive Interaction (ANNAI) theory to perform course-keeping, turning and track-keeping control. A strategy for automatic selection of the neural network controller parameters is introduced to improve the adaptation ability and the robustness of new ANNAI autopilot. In Part II of the paper, to show the effectiveness and feasibility of the proposed ANNAI autopilot, computer simulations of course-keeping and track-keeping tasks with and without the effects of measurement noise and external disturbances will be presented.

• Journal of Navigation and Port Research
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• v.31 no.7
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• pp.563-568
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• 2007

In this paper, an adaptive neural network controller and its application to automatic berthing control of ship is presented. The neural network controller is trained online using adaptive interaction technique without any teaching data and off-line training phase. Firstly, the neural networks used to control rudder and propeller during automatic berthing process are presented. Secondly, computer simulations of automatic ship berthing are carried out in Pusan bay to verify the proposed controller under the influence of wind disturbance and measurement noise. The results of simulation show good performance of the developed berthing control system.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.288.1-288
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• 2000

No Abstract, See Full Text

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.251-254
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• 2004

The aging diagnosis technique using partial discharge detection method detects partial discharge signals cause of power equipment failuer and able to forecast the aging state of insulation system through analysis algorithm, in this paper accumulates HFPD signal during constant scheduled cycles to build HFPD pattern and then analyzes HFPD pattern using statistical parameters and ${\Delta}F$ pattern. The 3D pattern is composed of detected signal frequency, amplitude and repeated number and the FRPDA(frequency resolved partial discharge analysis) technique is used in 3D pattern construction. The ${\Delta}F$ pattern shows variation characteristics of amplitude gradient of consecutive HFPD signal Pulses and able to classify discharge types-internal discharge, surface discharge and coronal discharge etc. Fractal mathematics applied to ${\Delta}F$ pattern quantification and neural networks is used in aging diagnostic algorithm.

• Journal of Korea Port Economic Association
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• v.33 no.2
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• pp.1-18
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• 2017

By using social network analysis, this study examined 102 countries, 281 ports, and 6,318 maritime routes associated with the global network of the Maersk Line. With the 'Belt and Road' in place, China is developing ports, expanding the cooperation with major ports, and increasing its influence on maritime transport. China's ports' reform and development implies establishing stable and independent logistic networks for supply of raw materials as well as exports and imports. This is closely related not only to individual ports' competitiveness, but also to relational structures between maritime powerhouses such as the US-which has the largest share and influence in the global market-and the surrounding countries. In this regard, an analysis of the maritime transport needs to consider the characteristics of individual ports together with those of each country. This study identified the characteristics of each port in light of the relationships in the global network of Maersk and applied them to each country. Moreover, the individual networks of China, the US, and Korea are compared. The findings showed that China, the US, Panama, Malaysia, and Spain accounted for large shares of the global network, while the shares of China, Korea, Taiwan, and Vietnam were high in China's network. In addition, by comparing individual networks of China, the US, and Korea, it emerged that Korean ports such as Busan and Gwangyang had secured a high level of competitiveness in the Chinese network.

• Journal of Navigation and Port Research
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• v.42 no.2
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• pp.117-126
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• 2018

Container port is one of the most vital link of the transportation chain that plays an important role in trading with other countries. Having a proper understanding of port operations could change the role of the port from a transportation node to an efficient point in a transportation chain. Development of transportation chains, logistics and progress of these networks have enhanced the sustainable condition and level of transportation. Therefore, evaluating the competitiveness of ports is obligatory for port users to make a decision in investment or exploitation. This paper introduces the use of Fuzzy C-means and TOPSIS for competitiveness comparison among a sample of container terminals in Korea and China and determine how to improve Korean port competitiveness and particularly in Busan port.

• Asian review of World Histories
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• v.4 no.2
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• pp.179-189
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• 2016

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.6
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• pp.1148-1156
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• 2015

The maritime cognitive radio networks (MCRNs) provide the high throughput with a low communication cost because the secondary ships opportunistically access to unused licensed bands of primary ships. In the ground cognitive radio networks, the busy and idle state of a primary user during a frame is not nearly changed because the state of the primary user are slowly changed. However, the state of the primary ship in the MCRNs may be frequently changed in the frame. Therefore, this paper evaluates the throughput of a primary ship and secondary ships in the MCRNs taking the state change of a primary ship into consideration when the fusion center uses the cooperative spectrum sensing. The simulation results show that trade-off between the throughput of a primary ship and that of secondary ships according to the system parameter such as the cooperative spectrum sensing scheme, the number of secondary ships, and the target detection probability.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.213-216
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• 2005

The distress communication system in the maritime mobile service had almost depended on the wireless telephony or telegraphy technique. The GMDSS (Global Maritime Distress and Safety System) which was introduced in 1992 brought a lot of changes in the maritime distress communication service such as the automatic transmission of distress signals and implementation of global search and rescue networks. However, there are some deficiencies in the GMDSS distress communication system such as a lack of compatibility in the maritime distress communication between GMDSS ships and Non-GMDSS ships, increasing deceptive or false distress alerts generated by GMDSS installations, lack of understanding about the GMDSS installations for the operators. In this paper, the problems of distress communication system in the maritime mobile service are analyzed and the methods to solve or minimize these problems are suggested.