• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.4
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• pp.31-37
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• 2008

Conventional cooperative communications can attain gain of spatial diversity and path loss reduction because destination node independently received same signal from source node and relay node located between source node and destination node. However, these techniques bring about decreased spectral efficiency with relay node and increased complexity of receiver by using maximal ratio combining (MRC). This paper has proposed cooperative ARQ protocol that can improve the above problems and can get the better performance. This method can increase the spectral efficiency than conventional cooperative communication because if the received signal from source node is satisfied by the destination preferentially, the destination transmits ACK message to both relay node and source node and then recovers the received signal. In addition, if ARQ message indicates NACK relay node operates selective retransmission and we can increase reliability of system compared with that of general ARQ protocol in which source node retransmits data. In the proposed protocol, the selective retransmission and ARQ message are to be determined by comparing log-likelihood ratio (LLR) computation of received signal from source node with predetermined threshold values. Therefore, this protocol don't waste redundant bandwidth with CRC code and can reduce complexity of receiver without MRC. We verified spectral efficiency and BER performance for the proposed protocol through Monte-Carlo simulation over Rayleigh fading plus AWGN.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.3
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• pp.36-45
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• 2011

An agent in collaborative e-learning has independent function for learners in any circumstance, status and task by the reasonable and general means for social learning. In order to perform it well, communication among agents requires standardized and regular information technology method. This study suggests data model as a communication tool for various agents. Therefore this study shows various agents types for collaborative learning, designation of rule for data model that enable to communicate among agents and data element of agent communication data model. A multi-agent e-learning system using like this standardized data model should able to exchange the message that is needed for communication among agents who can take charge of their independent tasks. This study should contribute to perform collaborative e-learning successfully by the application of communication data model among agents for social learning.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1023-1026
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• 2005

In the ubiquitous computing environment, an intelligent vehicle is defined as a sensor node with a capability of intelligence and communication in a wire and wireless network space. To make it real, a lot of problems should be addressed in the aspect of vehicle mobility, in-vehicle communication, common service platform and the connection of heterogeneous networks to provide a driver with several intelligent information services beyond the time and space. In this paper, we present an intelligent information system for managing in-vehicle sensor network and a vehicle gateway for connecting the external networks. The in-vehicle sensor network connected with several sensor nodes is used to collect sensor data and control the vehicle based on CAN protocol. Each sensor node is equipped with a reusable modular node architecture, which contains a common CAN stack, a message manager and an event handler. The vehicle gateway makes vehicle control and diagnosis from a remote host possible by connecting the in-vehicle sensor network with an external network. Specifically, it gives an access to the external mobile communication network such as CDMA. Some experiments was made to find out how long it takes to communicate between a vehicle's intelligent information system and an external server in the various environment. The results show that the average response time amounts to 776ms at fixed place, 707ms at rural area and 910ms at urban area.

• Journal of Science of Art and Design
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• v.3
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• pp.5-32
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• 2001

At the beginning of 21st Century, human desire of communication is forwarding to the Cosmos The way of Communication is going to be not by simple methodology but by the complicated methodology with high technology. It will not be monologue communication but be interactive communication, that will make intelligence Infra, which could be able to communicate from the location of information is present to which is not present; and the multi-media which will be able to solve the technical problems of these communication; will be developed continually. In the genre of plastic art, there are no exception in these changedness. More developed and proceed to develope intermedia could be able of intercommunication. The more development of technology could be able to the more development of new plastic art. Furthermore the development of science make the genre of art to be changed. There are no exception of this changedness in any part of society, The art always has been guided by the person who has proceeding idea for new value. The 21st century plastic art will be in the procedure of the intercommunication. Human-being's concern is to communicate with Universe, and that will be multi-dimension$(4{\cdot}5{\cdot}6{\cdot}7{\cdots}dimension)$ communication beyond our usual recognition. To conjoin this, the possibility of cyber space expressing is going to be considered, and the way is being done by the development of the Media Art, which is able to go and back to the cyber-space. And the message will be so complicate beyond our recognition. Because we will need to communicate with various newly-built vocabulary, so we need to magnify the repertories of new vocabulary.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.8
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• pp.1654-1660
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• 2004

In this paper, we describes the design and implementation of LonWorks communication module for distributed intelligent control using LonWorks technology of Echelon. LonWorks communication module can be divided hardware and firmware. First, hardwares is divided into microcontroller attaching sensors and LonWorks components for working together control network and data network. Hardwares are consisted of neuron chip, microcontroller, transceiver, LONCard. Second, operating firmware is realized with neuron C using NodeBulider 3.0 development tool. Produced and implemented LonWorks communication module is pretested using LTM-10A, Gizmo 4 I/O board, parallel I/O Interface. For field test, microcontroller module part is tested by HyperTerminal, communication procedure in data network is certified by transmitting and receiving short message using LonMaker for Windows tool. Herewith, LON technology is based on network communication technique using LonWorks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.4
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• pp.313-318
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• 2002

The Integration of agent technology and security technology is needed to many application areas like electronic commerce. This paper suggests a model of extended multi-agent engine which supports privacy, integrity, authentication and non-repudiation on agent communication. Each agent which is developed with the agent engine is composed of agent engine layer and agent application layer. We describe and use the concepts self-to-self messages, secure communication channel, and distinction of KQML messages in agent application layer and messages in agent engine layer. The suggested agent engine provides an agent communication language which is extended to enable secure communication between agents without any modifications or restrictions to content layer and message layer of KQML. Also, in the model of our multi-agent engine, secure communication is expressed and processed transparently on the agent communication language.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.12
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• pp.2232-2240
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• 2017

IMO has made AIS and VHF mandatory for international sailing vessels through SOLAS, and korea if mandating specific vessels through the law for safety of vessels and the ship installation technology standards. However, due to various communication equipments and complicated usage method, malfunction occurs, and the response delay to the actual structure signal often causes human accidents. So recently, as a part of GMDSS modernization, maritime communication devices are attempting to interwork and integrate different types of marine communication system in order to construct a next generation maritime communication system. In this paper, we describe a technique to implement the DSC function by interlocking and integrating the AIS device and VHF. We will present the basis for achieving domestic technical standards and standardization through the linking algorithm of the data that can extract the ship information from AIS and utilize it the DSC function of VHF.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.6
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• pp.113-119
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• 2017

The Rich Communication Service(RCS) is a next generation mobile messaging service. Since it has been developed and managed by a wireless service provider, 3rd party application developers cannot utilize the RCS features in their apps. A few studies have been proposed to solve this problem, even though they were not viable level of deployment. This paper presents a Web-based Rich Communication Service Software Framework(WebRSF) to help the 3rd party application developers adopt RCS features easily. WebRSF converts complicated RCS protocols to simple web-based protocols for providing the RCS 1-to-1 chat service to the 3rd parties. Communication protocols between WebRSF and its clients are defined in this paper. Also, a network configuration diagram and a message flow diagram are defined. Finally, performance evaluation between the WebRSF client and the RCS client are performed to simulate the load on clients' devices. It shows that the WebRSF client has 17% less loads than the RCS client while initiating sessions, and has 25% more loads after initiating sessions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.5
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• pp.9-17
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• 2015

The development of wireless communication technology and change in the ICT market has led to the development of the M2M service and technology. Under these circumstances, the M2M environment has been the focus of communication environment construction between machines without control or direct intervention of human being. With characteristics of wireless communication environment, the possibility of being exposed to numerous security threats and safe communication security technology have becoming an issue an important requirements for problems such as data exposure, forgery, modulation, deletion, and privacy. This research analyzes requirements of trapdoor collision hash, generates keys between groups under the M2M environment by using the specificity of trapdoor, and suggests technology to exchange keys with session keys. Further, it also suggests techniques to confirm authentication of device and gateway in accordance with group key generation. The techniques herein suggested are confirmed as safe methods in that they have attack resistance such as Masquerade Attack, Man-in-the-Middle Attack, and Replay Attack in the group communication block by using the speciality of collision message and collision hash.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.99-106
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• 2017

Audible Pedestrian Signal(APS) is an additional equipment to provide information about pedestrian signals in non-visual formats such as audible tones and verbal messages. It can provide information to pedestrians about the location and directions of a crosswalk, and the traffic signal status. In general, a pedestrian who is visually impaired uses a 358.5MHz wireless remote controller to activate the APS and crosses at the crosswalk with the help of the APS. The existing APS can only receive an activation message from the remote controller. Therefore, the APS has an issue, especially at intersections, that all APSs within the communication range of the remote controller are activated simultaneously. It makes to confuse the visual impaired pedestrians. In this paper, we propose a BLE-enabled APS that can enable two-way communication via Bluetooth with a smartphone. The proposed system solves the problem and provides them with additional information, so that visually impaired pedestrians can cross at the crosswalk more conveniently.