• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.623-629
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• 2010

A geographical routing protocol is typically utilized for a route selection of VANET. Even if it is conceptually well adapted into VANET, message delivery tends to be unreliable with frequent network partitions, which mainly come from the inherent characteristics such as high mobility and irregular traffic density. In this paper, we deal with a method to enable reliable message delivery with reflecting the traffic density on routing decision. By concatenating the message delivery cost of each of inbetween junction section, $1^{st}$ and $2^{nd}$ shortest paths are initially determined. When it is not possible to deliver the message on a junction on the 1st path, we utilize two novel ideas, that is, letting the message stay on the junction to find out a new relay node, and putting a replicated copy to reach via a detour path. By using the NS-2 network simulator, our method has been examined in terms of message delivery rate and delay. It shows that our method is much efficient than the other method in the low density environment, while it brings similar results in the high density environment.

• Journal of Information Processing Systems
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• v.11 no.3
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• pp.465-482
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• 2015

IEEE 802.11p is a standard MAC protocol for wireless access in vehicular environments (WAVEs). If a packet collision happens when a safety message is sent out, IEEE 802.11p chooses a random back-off counter value in a fixed-size contention window. However, depending on the random choice of back-off counter value, it is still possible that less important messages are sent out first while more important messages are delayed longer until sent out. In this paper, we present a new scheme for safety message scheduling, called the enhanced message priority mechanism (EMPM). It consists of the following two components: the benefit-value algorithm, which calculates the priority of the messages depending on the speed, deceleration, and message lifetime; and the back-off counter selection algorithm, which chooses the non-uniform back-off counter value in order to reduce the collision probability and to enhance the throughput of the highly beneficial messages. Numerical results show that the EMPM can significantly improve the throughput and delay of messages with high benefits when compared with existing MAC protocols. Consequently, the EMPM can provide better QoS support for the more important and urgent messages.

• Journal of Korea Multimedia Society
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• v.19 no.2
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• pp.317-324
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• 2016

This paper proposes a message transfer application using smartphone with NFC(Near Field Communication) and GCM(Goolge Cloud Messaging) technology for prevention of personal information leakage. In implementing for the proposed system, we design a NFC-based vehicle status alerts service which make it possible to communicate with smartpone message without phone-number between a car driver and an unspecified person. The application provides message communication mechanism without exposing the real phone number, using the NFC tag written with the driver's smartphone device ID and GCM push messages. Through the evaluation result of the actual implemented application, the proposed system can be efficient technology in protection for leakage of personal information such as personal phone- number in daily life.

• Journal of the Korea Society of Computer and Information
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• v.21 no.4
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• pp.17-24
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• 2016

In this paper, we propose a AH LSU(Advanced Hybrid QoS Routing Link State Update) Algorithm that improves the performance of Hybrid LSU(Hybrid QoS Link State State Update) Algorithm with statistical information of flow holding time in network. AH LSU algorithm has had both advantages of LSU message control in periodic QoS routing LSU algorithm and QoS routing performance in adaptive LSU algorithm. It has the mechanism that calculate LSU message transmission priority using the flow of statistical request bandwidth and available bandwidth and include MLMR(Meaningless LSU Message Removal) mechanism. MLMR mechanism can remove the meaningless LSU message generating repeatedly in short time. We have evaluated the performance of the MLMR mechanism, the proposed algorithm and the existing algorithms on MCI simulation network. We use the performance metric as the QoS routing blocking rate and the mean update rate per link, it thus appears that we have verified the performance of this algorithm.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.982-984
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• 2005

효과적인 어플리케이션 로그처리는 어플리케이션 개발 및 운영 시에 매우 중요한 요소 중에 하나이다. 파일이나 콘솔을 이용하여 동기식으로 처리되는 일반적인 로그 서비스는 동시에 대량의 로그를 처리해야 할 경우 시스템에 많은 부하를 주게 되는 문제점이 있다. 이를 해결하기 위해서는 클라이언트가 지연 없이 로그를 남길 수 있는 비동기식 로그서비스가 필요하다. 이 논문에서는 비동기식 로그서비스 구현을 통해서 Message-Driven POJO(MDP) 구현 기술을 소개하고 최근에 소개된 EJB 3.0 Message Driven Bean(MDB) 기술과 비교 분석해 보도록 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.11
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• pp.1029-1043
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• 2013

We introduce Approximate Message Passing (AMP) algorithm which is one of the efficient recovery algorithms in Compressive Sensing (CS) area. Recently, AMP algorithm has gained a lot of attention due to its good performance and yet simple structure. This paper provides not only a understanding of the AMP algorithm but its relationship with a classical (Sum-Product) Message Passing (MP) algorithm. Numerical experiments show that the AMP algorithm outperforms the classical MP algorithms in terms of time and phase transition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.2C
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• pp.173-180
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• 2012

It is important to consider saving location of message structures, structure of parser and creating method of parser generator for adopting KVMF to increase interoperability among different weapon systems. Especially, it requires to design the message parser by analyzing performance and maintenance when we adopting KVMF to previously developed weapon systems. In this paper, we propose the method of concurrent dynamic message processing for KMVF message based on KVID to support the developed and next-developed weapon systems. We show message conversion accuracy and performance effectiveness by adopting proposed method to Batallion Tactical Combat System.

• Management & Information Systems Review
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• v.32 no.4
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• pp.209-225
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• 2013

The effects of message framing have been major research themes in marketing and advertising field and several studies on these effects have been conducted. The purpose of this study is to examine the direct effects of public service Advertising message framing and moderating role of temporal distance. The results indicate that message types have a significant effect on message reliability and acceptance intention. In addition, temporal distance plays a significant moderating role between the message types and the dependent variable. The results of this study suggest various implications in the public service advertising area.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.9
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• pp.3104-3123
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• 2022

The development of Vehicular Ad hoc Network (VANET) has greatly improved the efficiency and safety of social transportation, and the routing strategy for VANET has also received high attention from both academia and industry. However, studies on dynamic matching of routing policies with the message types of VANET are in short supply, which affects the operational efficiency and security of VANET to a certain extent. This paper studies the message types in VANET and fully considers the urgency and reliability requirements of message forwarding under various types. Based on the diversified types of messages to be transmitted, and taking the diversified message forwarding strategies suitable for VANET scenarios as behavioral candidates, an adaptive routing method for the VANET message types based on reinforcement learning (RL) is proposed. The key parameters of the method, such as state, action and reward, are reasonably designed. Simulation and analysis show that the proposed method could converge quickly, and the comprehensive performance of the proposed method is obviously better than the comparison methods in terms of timeliness and reliability.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10a
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• pp.40-41
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• 2007