• Journal of the Korean Society of Marine Environment & Safety
• /
• v.22 no.4
• /
• pp.311-318
• /
• 2016

The VTS concept was located as a principal methods of maritime safety administration in world's major harbors and expected to become the pivotal role for the future of the maritime and harbor society with e-Navigation epoch. If recent limelight concept of big-data has been included in aspect of information gathering and analysis with various studies, it's required advanced studies to improve the information analysis capability and application range of the data that can be mining by the VTS. In this study, contrast to other studies that aimed quantitative analysis as communication number, it can be mining the time information and each of the communication VTS for the target vessel, including qualitative analysis, such as the purpose or the type of communication. This comparison across multiple items of the collected information, and presenting the VTS data mining model (VCDF) that can be analyzed for the purpose of analyzing way, type and number of communication by ship's type, also number of violations through VTS communication. First, In Busan port case, it shows frequently information service and shows frequently communicating with particular types of vessels. Second, Passive VTS carried out notwithstanding many kinds of traffic violations due to communication congestion. This arranged information can be used as data for the analysis, as possible the level of traffic for VTSO situational awareness, which pointed to the 'workloads' in 'IALA Guideline' and could be used as a database for future research of e-Navigation.

• Journal of Korea Port Economic Association
• /
• v.30 no.3
• /
• pp.59-87
• /
• 2014

The purpose of this study is to examine the effect of two kinds of Master and Chief Engineer's communication style on group conflicts and members' attitude including job satisfaction and organizational commitment, and to analyze the moderating effect of the isolation from home and community on the relation between the both of communication styles and the several behavioral variables in ship organization. This empirical result demonstrates the fact that Master and Chief Engineer's direct communication with crew has lower conflict and higher job satisfaction and organizational commitment than their indirect one through Chief Officer and First Engineer. In addition, it illustrates the isolation from home only effects moderately on the relation between the communication style and group conflict, and also the direct communication style reduces more the conflict in the group to show less isolation from home. To conclude, this study reveals that job satisfaction and organization commitment could be heightened by proper communication style of Master and Chief Engineer and it would utilize the job performance of ship organization in the long-term.

• Journal of Navigation and Port Research
• /
• v.41 no.6
• /
• pp.395-400
• /
• 2017

As a serial communications protocol, Modbus has become a practically standard communication protocol and is now a commonly available means of connecting industrial electronic devices. Therefore, all devices can be connected using the Modbus protocol with the measurement and remote control on ships, buildings, trains, airplanes and more. The existing Modbus that has been used is based on serial communication. Modbus TCP uses Ethernet communication based on TCP / IP which is the most widely used Internet protocol today; so, it is faster than serial communication and can be connected to the Internet of Things. In this paper, we designed an algorithm to control LED lighting in a wireless Wi-Fi environment using the Modbus TCP communication protocol, and designed and implemented a LED controller circuit that can check external environmental factors and control remotely through the integrated management system of a ship. Temperature, humidity, current and illuminance values, which are external environmental factors, are received by the controller through the sensors, and these values are communicated to the ship's integrated management system via the Modbus protocol. The Modbus can be connected to Master devices via TCP communication to monitor temperature, humidity, current, illuminance status and LED output values, and also users can change the RGB value remotely in order to change to the desired color. In addition, in order to confirm the implementation of the controller, we developed a simulated ship management system to monitor the temperature, humidity, current and illumination conditions, and change the LED color of the controller by changing the RGB value remotely.

• Journal of Navigation and Port Research
• /
• v.45 no.6
• /
• pp.352-359
• /
• 2021

This paper presents the definition and importance of ship-centric direct communication concerning ship safety of maritime autonomous and unmanned ships. It also proposes the concept of MX-S2X communication based on high frequency for wide-bandwidth technology and describes the design and simulation result for the physical layer of MX-S2X. It considered high-speed communication as well as overcoming maritime multi-path fading required to be resolved in the marine environment. The physical layer of MX-S2X communication was designed to overcome the occurrence of error-floor caused by multi-path fading even with receiving sufficient signal strength. To this purpose, a performance analysis was conducted on the physical layer by applying the channel model of the actual maritime communication environment. As a result of the performance analysis of the MX-S2X physical layer, it was confirmed that the BER error-floor observed in the VDE physical layer test was overcome, and it operated within the SNR 2dB degradation range compared to the AWGN channel. It is expected that this will show enough performance suitable for short-distance ship-centered direct communication and can be used for direct communication of maritime autonomous ships, unmanned ships, and group navigation of themshortly.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2001.10a
• /
• pp.19-25
• /
• 2001

At present the identification of vessels is still depending on the OOW (Officer Of Wateh) in VTS (Vessel Traffic Service), which is completed by radar, and also by the combination of VHF radio and VHF direction finder. However, with the development of port transportation and economic, this conventional way of identification can't satisfy more and more request for the information that the VTS needs from the vessels. In such a case, the AIS(Automatic Identification System) precept which is based on STDMA (Self-organized Time Division Multiple Access) technique is put forward by IMO (International Maritime Organization). AIS can automatically provide the information, including own ship's identification, type, position, course, speed, and other information to the appropriately equipped coast station and other ships. At the same time it can also automatically monitor and track the nearby ships similarly fitted with AIS. On the basis of describing the whole comprising and the format of transmission information of AIS, this paper mainly studies the key communication techniques in AIS, such as STDMA protocol, net synchronization and GMSK(Gaussian Minimum Shift Keying)technique, and so on. At last this paper briefly introduces the recommendation decided by IMO on forcing the sea-going ships to fixed with AIS equipments, and it continuos with the unexploited potential of AIS if it applies in VTS.

• Journal of the Korean Institute of Navigation
• /
• v.24 no.3
• /
• pp.167-176
• /
• 2000

The -advent of electronic navigation equipment and trustworthy computer which provides people with convenience made the management system by one-man bridge operation or the least people who are needed possible through the integration of communication network with various navigation equipment and related institution. One of the most needed ultra-modem navigation device for a mate, ECDIS is a core equipment for navigation in ENS that notifies peril to mate as well as supervises all tasks in hydrographical chart, voyage planning, course monitoring and voyage recording. We should make coast and ocean voyage planning first, for the secure navigation which is considering the course circumstances and next, for the reduction of voyage dates in economical aspect. There needs a thoughtful consideration about the feature of the ship itself and the course with weather condition in taking up the course and also we have to take into accounts about appropriate distance between ships. Considering the essential conditions of ECDIS the indispensable device in the future, it was developed the basic principle for voyage planning algorithm for officer and programmed to real implementation available. In this paper including most of the requirements in ECDIS performance standard I mentioned about such a basic and a core Principle with real application by using the Visual C++ programming language. The voyage plan includes the function that indicate and modifies all the way points in the course from department port to arrival port with erasing the wrong way points. Also, it provides in a document form that shows ETA at glance in average speed sailing.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.3
• /
• pp.384-389
• /
• 2003

A new two-step soft-output Viterbi algorithm (SOVA) decoder architecture is presented. A significant reduction in the decoding latency can be achieved through the use of the dual-port RAM in the survivor memory structure of the trace-back unit. The system complexity can be lowered due to the determination of the absolute value of the path metric differences inside the add-compare-select (ACS) unit. The proposed SOVA architecture was verified successfully by the functional simulation of Verilog HDL modeling and the FPGA prototyping. The SOVA decoder achieves a data rate very close to that of the conventional Viterbi Algorithm (VA) decoder and the resource consumption of the realized SOVA decoder is only one and a half times larger than that of the conventional VA decoder.

• Journal of the Korean Institute of Navigation
• /
• v.20 no.3
• /
• pp.43-63
• /
• 1996

The purpose of this study is to find out what is the functional role of VTS in order to get the people concerned with marine traffic/transportation understand about VTS. VTS could be described as the essential risk management system in both cost effective on cost-benefit analysis and the sea space or time management at port, coastal environment. The important role of the VTS are those functions such as the decision making infrastructure, the passive/active safety measures at sea. VTS could not control/regulate marine traffic as strong as ATC(Air Traffic Control) owing to the marine traffic characters. However, the right and responsibility of VTS finally are belong to the master, pilot and mariners. For the benefit of the electronic technology development, VTS system also cloud be upgraded to communication system from information system. In connection with these system upgrading, the right and responsibility of VTS/staff should be supported by domestic legal system. The followings are presented for VTS to be effective. First, the cooperation and understanding of VTS between the peoples concerned with marine traffic/transportation are essential. Because they are all data supplier and also information consumers. Second, VTS staff/regulator should be selected, educated, trained accordingly as per their career, ability, quality, qualification, certification and etc. Third, the port reliability from VTS users depends on the factors such as economic interests, safety and effectiveness/efficiency of VTS.

• Proceedings of the KIEE Conference
• /
• 2005.07a
• /
• pp.102-104
• /
• 2005

This paper describes the model of the distribution grid for the broadband power line communication based on lumped-element circuits. In addition, this paper discusses various configurations of the MV distribution network in PLC. The distribution grid is not designed for communication so that it involves unfriendly conditions for PLC. The characterization of the MV distribution grid for PLC should be determined such as noise, attenuation, and mismatched impedance. For theses reasons, the PLC networks is described in using the scattering parameters. Finally, the n-port network is explained.

• Journal of the Korean Institute of Navigation
• /
• v.22 no.4
• /
• pp.21-29
• /
• 1998

The marine self-organizing VHF data link is a digital radio link with self-organizing ability, which exploits the STDMA algorithm and operates in marine VHF channels. It can support the applications of surveillance, situation awareness and communication. It is the core technology of the Universal AIS which is considered as a future surveillance system at sea by the IMO. In this paper, the operational principle of the marine self-organizing VHF data link is introduced. Simultaneously, a new access protocol is proposed to enhance the marine self-organizing VHF data link so as to support point-to-point communication. The point-to-point communication is one of the most important bases to establish dynamic internetworks among computers on the bridges in the future.