• Journal of KIISE:Software and Applications
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• v.35 no.10
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• pp.636-652
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• 2008

In this paper, we present a modular pointer analysis algorithm based on the update history. We use the term 'module' to mean a set of mutually recursive procedures and the term 'modular analysis' to mean a program analysis that does not need the source codes of the other modules to analyze a module. Since a modular pointer analysis does not utilize any information on the callers, it is difficult to design a precise analysis that does not lose the information related to the program flow or the calling context. In this paper, we propose a modular and flow- and context-sensitive pointer analysis algorithm based on the update history that can memory states of a procedure independently of the information on the calling context and keep the information on the order of side effects performed. Such a memory representation not only enables the analysis to be formalized as a modular analysis, but also helps the analysis to effectively identify killed side effects and relevant alias contexts.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.4
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• pp.803-809
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• 2011

In this paper, we present a very useful method for updating digital satellite radio broadcast channel information. When a devices equipped with function to receive Digital Satellite Radio such as Home Theater, MP3 player, mobile phones, car audio system and various other types of Digital Devices, receives new Digital satellite radio (will be mentioned as XM radio onwards) broadcast channel information, only the current received XM radio broadcast channel and N number of pre/post nearby broadcast channels are scanned randomly in zigzag manner. Then the previous XM radio broadcast channel information updated with the newly received XM radio broadcast channel information. Since this method can prevent batch update for all XM radio channel, including some channels which less likely did not select by user, update process for real time frequently changed XM radio broadcast channel information can be performed efficiently with minimal or without delay.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2143-2149
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• 2012

DVB-S2 employs LDPC codes which approach to the Shannon's limit, since it has characteristics of a good distance, error floor does not appear. Furthermore it is possible to processes full parallel processing. However, it is very difficult to high speed decoding because of a large block size and number of many iterations. This paper present HSS algorithm to reduce the iteration numbers without performance degradation. In the flooding scheme, the decoder waits until all the check-to-variable messages are updated at all parity check nodes before computing the variable metric and updating the variable-to-check messages. The HSS algorithm is to update the variable metric on a check by check basis in the same way as one code draws benefit from the other. Eventually, LDPC decoding speed based on HSS algorithm improved 30% ~50% compared to conventional one without performance degradation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.1B
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• pp.39-49
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• 2012

With group mobility, minimizing routing overhead among intra-group nodes can be achieved by making longer the routing update period, which may lead to degradation of inter-group's routing performance and consequently the inter-group packet delivery success ratio will be decreased. To reduce the inter-group routing overhead without lowering the inter-group packet delivery success ratio, a mobility-adaptive routing update(MARU) scheme is proposed in this paper. Main idea of the proposed scheme is group-based mobility prediction and updating routing paths by selecting intermediate common relay groups.

• Journal of the Korea Society for Simulation
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• v.15 no.1
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• pp.27-33
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• 2006

To guarantee QoS (Quality of Service), routers should determine routing paths satisfying service requirements, based on link state information as well as network topology. Link status database (LSD) in routers should be efficiently managed to effectively reflect the current state of all links. However, there is a trade off between the exact reflection of the current link status and its update cost. For exactly reflecting the current link status, each router immediately notifies its neighbors that link state information is changed. This may degrade performance of the router due to the processing of link state update messages. On the other side, if the current link state information is not updated appropriately, a route setup request can be rejected because of the discrepancy between the current link state information and previously updated link state information in LSD. In this paper, we propose a traffic variation based link state update algorithm for adaptively controlling the generation of link state update messages and compare its performance with those of four existing algorithms by intensive simulations.

• Journal of the Korea Society of Computer and Information
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• v.27 no.7
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• pp.137-144
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• 2022

This study is an empirical study on whether the interval of K-pop content updates and price changes consumer purchasing intentions for domestic fandom commerce platforms that turn their profit structure online and strengthen fandom-based marketing to cope with changes in the digital environment. FGI and a survey was conducted using a conjoint analysis designed to confirm the difference in price elasticity according to the content update interval. As a result, the price elasticity of K-pop content was found to be an inelastic characteristic, and the change in price elasticity according to the content update interval was not statistically significant. This study provides basic data to be used to establish a marketing strategy for the fandom commerce market that will grow in the future.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.945-948
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• 2011

기존의 모바일 IPv6에서 경로 최적화를 하기 위해 바인딩 업데이트를 할 때 RR 프로토콜을 사용한다. IPv6에서 바인딩 업데이트는 이동노드가 홈 네트워크에서 외부 네트워크로 이동했을 때 Home Agent와 Correspondent Node(CN)에게 전송하며 이 과정에서 몇 가지 취약점으 가지고 있다. HoIT와 CoIT 메시지는 서로 연관이 없으며 이동 단말과 HA사이에만 IPSec으로 보호된 터널이 존재하고 HA와 CN 사이에는 보호되지 않는다. 따라서 공격자는 CN과 가까이에 위치하여 자신의 CoA를 CN에게 CoIT를 보내 토큰을 받아서 CN과 바인딩 업데이트를 할 수 있다. 바인딩 업데이트가 끝나면 두 노드사이는 정상적인 통신을 할 수 있고 공격자에 의해 위험에 노출 될 수 있다. 또한 CoIT 메시지를 보내면 CN에서는 토큰을 생성하게 되므로 공격자가 다수의 기기를 획득해 CN에게 계속 CoIT를 보내면 계속 토큰을 만들어야 하므로 다른 정상적인 노드의 통신을 방해할 수 있다. 따라서 이 논문에서는 이러한 RR프로토콜에 대한 문제점을 분석하고 이러한 문제점을 해결 할 수 있는 개선 방안을 논의 해본다.

• Journal of the Korea Society of Computer and Information
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• v.9 no.3
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• pp.171-175
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• 2004

This paper proposes a seamless handoff scheme that enables a mobile node to continue a session when moving to an overlapping area. During handoff due to the weakness of signaling, mobile node makes new Care-of Addresses using signals received from access router when MN reaches the edge of its area in addition to its current CoA, and it sends temporary binding update messages to Mobility Anchor Point which manage the area covering MN. MAP receives that binding update messages from MN, and temporarily stores new binding informations from them to its binding cache besides existing binding information for MN. This scheme ensures a seamlessly handoff using multicasting until MN enter a new access router area and sends a confirmed binding update message to MAP.

• Journal of Korea Multimedia Society
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• v.14 no.7
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• pp.949-963
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• 2011

Generally, It is indispensible to use an ISP(In System Programming) tool for upgrading, patching, or changing the system software of the each sensor nodes in wireless sensor networks. While under a small number of nodes, the upgrading task is not a serious burden, however if there are a large number of nodes to be updated, the task is almost impossible to do for the given constrains such as limited budgets and resources. Based on this observation, in this paper we have proposed a novel upgrading scheme based on a single hop in IEEE 802.15.4 PAN(Personal Area Network)s. Simulation results have shown the scheme outcomes the conventional methods in the performance measures.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.743-747
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• 2009

We designed and implemented an automatic update system of 네비게이션 contents. Currently car users are updating map contents of their 네비게이션 system by using SD memory card. In the implemented system, map contents are downloaded via WI-FI internet access while served in a gas station. To prevent free rider at gas stations, we adopted authentication mechanism based on MAC address.