• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.252-254
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• 2015

In the maritime field, desktop-based ENC systems and services have been used for supporting the safe navigation of ship. However, with increasing level of needs for mobile device-based marine information service, ENC systems that provides basis for maritime service needs to be ported to mobile device. It is difficult to directly port desktop ENC system to the mobile devices, because the system operating environment and methods such as process management and memory management of the mobile devices are different from the desktop. In this paper, we analyze the characteristics of the Android-based mobile devices. Based on this, during porting process of desktop-based ENC system to android system, we modified and improved the display module with the characteristics of Android-based mobile devices in mind.

• Journal of Navigation and Port Research
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• v.45 no.5
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• pp.231-237
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• 2021

Enhancing the performance of maritime wireless communication has been highlighted by the issue of cell planning in the sea area because of lack of an appropriate Propagation Loss Model (PLM). To resolve the cell planning issue in vast sea areas, it was essential to develop the (PLM) matching the intended sea area. However, there were considerable gaps between the prediction of legacy PLMs and field measurement in propagation loss and there was a need to develop the adjusted PLM (A-PLM). Therefore, cell planning was performed on this adjusted model, including modification of the base station's location, altitude, and antenna azimuth to meet the quality objectives. Furthermore, in order to verify the availability of the cell planning, Communication Service Quality Monitoring System (CS-QMS) was developed in the LTE-Maritime project to collect LTE signal quality information from the onboard equipment at regular intervals and to ensure that the service quality was high enough to satisfy the goals in each designated grid. As a result of verification, the success rate of RSRP was 95.7% for the intensive management zone (IMZ) and 96.4% for the interested zone (IZ), respectively.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.521-524
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• 2008

The existing mobile learning service is the method that provides data packets in real time. It has some problems of much data packet cost and transmission speed to provide the mobile learning service for messy capacity by the existing one. To solve the problems, a secondary storage device like USB is added to a mobile phone. In this paper, we suggest to implementation of the mobile learning system of the new method using secondary storage device.

• Journal of Korea Multimedia Society
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• v.15 no.10
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• pp.1212-1220
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• 2012

In this paper, a collision-free resource reservation scheme for WUSB (Wireless Universal Serial Bus) networks with WiMedia D-MAC (Distributed Medium Access Control). Since distributed characteristic of the WiMedia D-MAC supporting DRP (Distributed Reservation Protocol) scheme may cause lots of conflicts, overall performances of the WUSB with WiMedia D-MAC can be deteriorated. In addition, when we consider multi-hop environment, "mobile" hidden node problem due to mobility of WUSB devices can be happened, and it is a critical problem to mobile WUSB devices transceiving real-time QoS (Quality of Service) traffic. To tackle the problem, we propose a new DRP reservation mechanism to prevent DRP conflicts for multi-hop mobility support in WUSB networks with WiMedia D-MAC and show its improved performance via simulation results.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.34-41
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• 2013

In the smart life era where the majority of economically active population uses mobile devices, smart devices have formed a new service market. In this study, we developed a shipyard quality management application using mobile devices such as smart phones and tablet PCs. For this purpose, the problems were derived through the analysis of the quality management work on shipyard and the considerations were extracted to build a smart work environment by analyzing the case studies of smart work in other industrial fields. Among the shipyard quality management work, functions thought to be highly utilized when converted to a mobile system has been developed as a mobile application. The application was developed by applying an object-oriented component-based development (ooCBD) methodology, and is expected to improve the user experience and the efficiency of quality management operations in shipyard.

• Journal of Welding and Joining
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• v.32 no.5
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• pp.58-64
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• 2014

The shipbuilding industry is facing the various problems of less demand and oversupply owing to the global economic crisis and the increase in shipbuilding countries. Shipyards of the industry are making effort to strengthen their ability to handle the crisis via a smartwork technology for flexible working environment. In this study, we developed a smartwork system that manages the information in shipbuilding process with mobile devices such as smart phones and tablet PCs. To successfully apply the developed smartwork system to shipyards, we analyzed several best practices and management tasks of the shipbuilding processes. The developed system was designed by CBD approach that is a branch of service-oriented software engineering for reusability and flexibility on the system. As it is designed considering the flexible working environment, it supports to increase their productivity by reducing the time required to carry out tasks and by increasing the mobility required to manage work performance in field of shipyards.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.881-889
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• 2004

Using the ETC Service, it is now possible to charge a vehicle for driving pass a specific toll booth electronically, without the vehicle even having to slow down. The smart card and card reader used to collect tolls electronically have a serious problem which it dose not have a standard for the ETC system. In this paper, we suggest the ETC system using mobile phone to collect tolls efficiently instead of existing system which is consist of a Interface Module to connect between a mobile phone and OEE, a mobile phone to send the information of tollgate fees and OEE to communication with RSE of roadway in the vehicle. This primary focus of this system is the IM functions and protocol to assist of the existing mobile phone and OBE.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.3
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• pp.49-53
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• 2024

Maritime safety is a critical factor in protecting lives from accidents at sea and fostering a safer marine environment. In this study, we developed a TPMS device aimed at enhancing maritime safety, providing technological solutions for detecting accidents at sea and enabling swift responses. The device utilizes a Tube Pressure Monitoring System (TPMS) to detect tube expansion and is designed to collect real-time data and communicate with surrounding devices for rapid responses. Experimental results confirm the effective detection of pressure by TPMS (Tube Pressure Monitoring System) and stable data transmission and reception with the main IoT device. Additionally, a mobile app capable of receiving emergency alert messages and accessing information for rapid responses in emergency situations was developed. The developed device and mobile app encompass technology applicable not only in the maritime safety field but also in various other application areas, with potential for expanded application in real-world scenarios in the future. These results are expected to contribute to enhancing safety in the marine environment.

• Electronics and Telecommunications Trends
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• v.35 no.5
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• pp.14-29
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• 2020

The 6G mobile communication system will become a backbone infrastructure around 2030 for the future digital world by providing distinctive services such as five-sense holograms, ultra-high reliability/low-latency, ultra-high-precision positioning, ultra-massive connectivity, and gigabit-per-second data rate for aerial and maritime terminals. The recent remarkable advances in machine learning (ML) technology have recognized its efficiency in wireless networking fields such as resource management and cell-configuration optimization. Further innovation in ML is expected to play an important role in solving new problems arising from 6G network management and service delivery. In contrast, an approach to apply ML to a physical-layer (PHY) target tackles the basic problems in radio links, such as overcoming signal distortion and interference. This paper reviews the methodologies of ML-based PHY, relevant industrial trends, and candiate technologies, including future research directions and standardization impacts.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.527-528
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• 2022

It is not easy to identify the location of mobile terminals based on drones in the mountainous area, the densely populated urban area, or the space where mobile terminals can easily move by using equipments or modules that can recognize the location of sensors or mobile terminals with LBS (Location-Based Service). However, although the performance of GPS has developed due to the development of technology, it is still widely used in position recognition systems using GPS modules in the sea and onshore, and there is much room for more utilization. Currently, most of the existing sensor networks need to send at least three location information messages to mobile terminals with location information that a plurality of mobile base stations depend on GPS. However, location recognition of mobile repeaters that maintain a certain movement speed using acceleration sensors is necessary for efficient communication network connection.