• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.5
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• pp.979-985
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• 2016

In this paper, a distributed instant message system with multiple servers architecture which can distribute system load effectively using an extended media control channel has been presented. A media control channel provides establishing a reliable control channel and also keeping a reliable control channel between SIP server and client in the field of real-time media transport area. In this study, a new instant message system architecture which can distribute massive instant message including multimedia data to multiple servers has been presented. The presented instant message system architecture can distribute system load by extending media control channel. For this purpose, media control channel messages, which distribute system load to multiple servers dynamically according to increasing number of users, have been designed in our presented system. And, in our research, an exchanging procedures of media control channel messages between servers have also been presented. The performance of the proposed system has been analysed by simulation.

• Smart Media Journal
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• v.5 no.2
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• pp.42-50
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• 2016

In case of a emergency situation or a natural disaster, a warning notification system is an essential tool to notify at-risk people in advance and provide them useful information to survive the event. Although some systems have been proposed such as emergency alert system using android, SMS, or P2P overlay network, these works mainly focus on a reliable message distribution methods. In this paper, we proposed a novel design and implementation of a personalized warning notification system to help inform not only the at-risk people but also their family and friends about the coming disaster as well as escape plan and survival information. The system consists of three main modules: the user selection module, the knowledge based message generator, and message distribution modules. The user selection module collects the list of people involved in the event and sorts them based on their level of involvement (their location, working position and social relationships). The knowledge based message generator provides each person with a personalized message that is concise and contains only the necessary information for the particular person based on their working position and their involvement in the event. The message distribution module will then find a best path for sending the personalized messages based on trustiness of locations since network failures may exist in a disaster event. Additionally, the system also have a comprehensive database and an interactive web interface for both user and system administrator. For evaluation, the system was implemented and demonstrated successfully with a building on fire scenario.

• Journal of Internet Computing and Services
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• v.8 no.5
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• pp.11-20
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• 2007

This paper designs and implements a message passing library called JMPI (Java Message Passing Interface) which complies with MPJ (Message Passing in Java), the MPI standard Specification for Java language, This library provides some graphic user interface tools to enable parallel computing environments to be configured very simply by their administrators and JMPI applications to be executed very conveniently. Also in this paper, we implement two versions of systems using Socket and RPC which are both typical distributed system communication mechanisms and with three benchmark applications, compare performance of these systems with that of an existing system JPVM depending on the increasing number of the computers. Experimental results show that our systems outperform JPVM system in terms of various aspects and that the most efficient processing speedup can be obtained by increasing the number of the computers in consideration of network traffic through processing evaluation. Finally, we can see that, as the number of computers increases, using RMI to transmit a message is more effective than using object streams attached to sockets to transmit a message.

• KIISE Transactions on Computing Practices
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• v.23 no.1
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• pp.57-64
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• 2017

Short message service (SMS) is one of the most important communication methods for people who use mobile phones. However, illegal advertising spam messages exploit people because they can be used without the need for friend registration. Recently, spam message filtering systems that use machine learning have been developed, but they have some disadvantages such as requiring many calculations. In this paper, we implemented a spam message filtering system using the set-based POI search algorithm and sentence similarity without servers. This algorithm can judge whether the input query is a spam message or not using only letter composition without any server computing. Therefore, we can filter the spam message although the input text message has been intentionally modified. We added a specific preprocessing option which aims to enable spam filtering. Based on the experimental results, we observe that our spam message filtering system shows better performance than the original set-based POI search algorithm. We evaluate the proposed system through extensive simulation. According to the simulation results, the proposed system can filter the text message and show high accuracy performance against the text message which cannot be filtered by the 3 major telecom companies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5B
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• pp.520-530
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• 2004

A multidatabase system (MDBS) is designed to provide universal access to distributed data across multiple autonomous, heterogeneous local database systems (LDBSs). In this paper, we propose a global concurrency control (GCC) algorithm in MDBS. The proposed GCC algorithm adopts the idea of message ordering in group communication messaging system. A necessary condition of GCC algorithm is that global transactions are serialized in the same order at all LDBSs that they execute. n all operations of a transaction are bundled in a single message and the message arrives at LDBSs in the same order using message ordering property, each LDBS can perform subtransactions in the same order. As a result, message ordering allows to determine easily the relative serialization order of global transactions, and then it can support a local autonomy without any information about the serialization order of transactions executing locally.

• Journal of the Korea Society of Computer and Information
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• v.14 no.9
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• pp.67-74
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• 2009

The presence informations of users of Instant Messaging System In SIP(Session Initiation Protocol) environment are obtained by presence server, and message waiting indication event package is used to provide various message informations stored in the message server. In this paper, I have proposed a new method in which Extended CPL(Call Processing Language) has been applied to presence service to provide various functions to the users. A user of Instant Messaging System subscribes presence information and CPL scripts which describe his requirements, and presence server executes CPL scripts when instant messaging service is subscribed and notifies presence informations. Several CPL operation tags are added, and therefore various services which combine presence service and call processing can be provided in this system. Furthermore a new method has been proposed in which message server and presence server correlate in Instant Messaging System. When changes of message status informations occur, message server send these informations to the presence server, and presence server provides both presence informations and message status informations in extended format. As this method can be a substitute for message waiting indication event package, the system operating efficiency can be increased. The performance of this proposed system is evaluated by experiments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.645-648
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• 2017

The existing embedded tester used TCP and shared file system for log processing. In addition, the existing processing method was treated as 1-N structure. This method wastes resources of the tester for exception handling. We implemented a log processing message layer that can be distributed by messaging system. And we compare the transmission method using the message layer and the transmission method using TCP and the shared file system. As a result of comparison, transmission using the message layer showed higher transmission bandwidth than TCP. In the CPU usage, the message layer showed lower efficiency than TCP, but showed no significant difference. It can be seen that the log processing using the message layer shows higher efficiency.

• Journal of KIISE
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• v.44 no.8
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• pp.749-759
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• 2017

The weapon system based on voice call can cause delay, error or damage to the message during the exchange of information. Furthermore, since the weapon system has a unique message format, it has limited data distribution. Therefore, a Korea Variable Message Format(KVMF) has been developed in this study to utilize a standard sized data format to guarantee the transmission quality and minimize the transmission amount. The ground tactical data link system quickly and accurately shares tactical information by incorporating a field management system that utilizes the KVMF standard message in the mobile weapon system. In this study, we examine the possibility of performing the mission immediately by recovering the state of network joining when a normal/abnormal termination situation of the battlefield management system occurs.

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.21-27
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• 2017

The combat systems in Korea navy have been operating some kinds of tactical data link systems such as Link-11, ISDL and JTDLS. Each tactical data link system has the ability to transmit and receive tactical information like track, engagement, weapon information by using unique message of theirs. And each unique message has their own format. But a number of tactical data link system make combat effectiveness worse because their major functions are duplicated unnecessarily. So, many advanced countries are trying to make united data link system. Similarly, the combat systems in Korea navy will operate C4I data link system, and it is combined version current ISDL, KNCCS and JTDLS data link system. In this paper, we consider the development current tactical data link systems in Korea navy. Also, compare the characteristics between I-message used in ISDL and Host-Interface message used in C4I. From these results, we analyze advanced points about C4I data link system.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.6
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• pp.53-62
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• 2011

Although the demand of Variable Message Sign(VMS) has become pervasive in fulfilling the ITS policy, there are still several unsolved problematic issues. The most critical ones of them are inequality and inefficiency of providing traffic information. This paper proposes the Infra-free Variable Message Sign in order to provide useful informations such as road condition, weather, and traffic of the area, where constructing the infrastructure of communication and power supply is relatively very hard. First of all, the characteristics of infra-free Variable Message Sign are studied and analyzed in deep because of differences between normal Variable Message Sign and Infra-free Variable Message Sign in the configuration and the operating method due to the nature of the Infra-free Variable Message Sign. Futhermore, for effective power management of operating Infra-free Variable Message Sign with limited power acquired through stand-alone PV system, new battery connection structure and dynamically variable power managements for the differently shown messages on Variable Message Sign are proposed. The proposed structure in this paper can be applied to not only power management for Infra-free Variable Message Sign but also power management for the various applications using parallel connection battery system.