• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.3B
• /
• pp.390-397
• /
• 2010

This paper presents an effective IPTV channel control algorithm considering network utilization and channel zapping time. The proposed algorithm keeps maximum average channel zapping time of each subscriber in the tolerable range with low network bandwidth usage by adjusting the type of each channel and the number of additional intra frames inserted into each channel. Finally, experimental results are provided to show the performance of the proposed algorithm.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.45 no.5
• /
• pp.8-14
• /
• 2008

There are two a approaches for the Cognitive Radio(CR) development. One is 'Full CR', which Joseph Mitola III proposed, and another is 'Spectrum CR', which is currently being standardized. The target approach of this paper is the latter and we develop a Cognitive Engine(CE) and simulated a channel set management(CSM), which is a core function of CE. The Channel set management evaluates channel quality and Incumbent User(IU) vacancy possibility and classifies the channel set, which is performed by using channel state history. Especially, a very important function for the channel set management is a channel state prediction and this paper proposed a Hidden Markov Model(HMM) based channel state prediction and a method for increasing performance. Also, we applied the proposed method into our simulator and simulated channel state prediction. Through the simulation, we verified as we applied our proposed scheme, the performance of channel state prediction gets better and through comparing with RS and SS, we verified the HMM based Channel state prediction is better.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2006.05a
• /
• pp.115-119
• /
• 2006

The channel is one of the precious and limited resources in wireless networks. There are many researches on the channel management. Recently, the optimization problem of guard channels has been an important issue. In this paper, we propose an intelligent channel management technique based on the neural networks. An SRN channel alteration model is developed to generate the learning data for the neural networks and the performance analysis of system. In the proposed technique, the neural network is trained to generate optimal guard channel number g, using backpropagation supervised learning algorithm. The optimal g is computed using the neural network and compared to the g computed by the SRN model. The numerical results show that the difference between the value of g by backpropagation and that value by SRN model is ignorable.

• Korea Information Processing Society Review
• /
• v.8 no.6
• /
• pp.31-37
• /
• 2001

• Journal of Internet Computing and Services
• /
• v.24 no.1
• /
• pp.1-7
• /
• 2023

Recently, the technology of device-to-device(D2D) communication has been receiving big attention to improve the system performance since the amount of high quality/large capacity data traffic from smart phones and various devices of Internet of Things increase rapidly in 5G/6G based next generation cellular networks. However, even though the system performance of macro cells increase by reusing the frequency, the performance of macro user equipments(MUEs) decrease because of the strong interference from D2D user equipments(DUEs). Therefore, this paper proposes a dynamic channel management(DCM) scheme for DUEs to guarantee the performance of MUEs as the number of DUEs increases in next generation downlink cellular networks. In the proposed D2D DCM scheme, macro base stations dynamically assign subchannels to DUEs based on the interference information and signal to interference and noise ratio(SINR) of MUEs. Simulation results show that the proposed D2D DCM scheme outperforms other schemes in terms of the mean MUE capacity as the threshold of the SINR of MUEs incareases.

• Annual Conference of KIPS
• /
• 2009.11a
• /
• pp.549-550
• /
• 2009

본 논문에서는 기존 다자간 메시지 전송 시스템을 확장하여, 애플리케이션의 요구사항에 따라 여러 타입의 통신 채널을 임의의 개수만큼 간단히 생성하여 다자간 원격 상호작용을 지원하는 다중 채널 관리 방법에 대해 기술하고, 다자간 메시지 시스템 내부의 전송 메커니즘을 보다 효율적으로 확장시키는 방안을 논의한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.5C
• /
• pp.519-533
• /
• 2006

The number of channels specified in IEEE 802.15.4 Low-Rate Wireless Personal Area Networks(LRWPANs) is too few to operate many applications of WPANs in the same area. To overcome this limit, we introduce Virtual Channel, a novel concept to increase the number of available channels when various WPAN applications coexist. Basically, a virtual channel is a newly-created channel via superframe scheduling within the inactive period of a logical channel preoccupied by other WPANs. To maximize the coexistence capability of WPANs using virtual channels, we propose Least Collision superframe scheduler(LC-scheduler), its less complex heuristics both for a given single channel, and Virtual Channel Selector(VCS) to efficiently manage multiple available logical channels. In addition, a simple but practical synchronization method is developed to compensate different time drifts among coexisting WPANs. The simulation results demonstrate that a remarkable improvement on the coexistence capability of the 802.15.4 can be achieved through the proposed schemes.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.1A
• /
• pp.18-26
• /
• 2000

Yeung suggested[10] efficient channel management technique suitable for the mobility model in the hierachical cellular system. It improved the existing channel allocation techniques by additionally considering the user’s mobility, allocating the channel of microcell to low-speed mobiles, and the channels of macrocell to high-speed mobiles. In this paper, we have suggested new channel management technique, which is directly compared with those of Yeung’s system and existing model. Blocking probabilities for each model are found through the queuing analysis and we have shown that our proposed system outperforms the both.

• Proceedings of the Korea Database Society Conference
• /
• 2001.06a
• /
• pp.158-171
• /
• 2001

o 경쟁력의 근원 : 정보와 속도 - 정확하고 질 높은 정보 제공 및 신속한 대응이 필수적 - 고객의 요청에 대응하는 방식에 따라 E-Biz의 성패가 좌우됨 o 고객과의 상호작용 형태 변화 - 판매원, 전화, 팩스에서 전자우편을 필두로 한 인터넷 환경으로 - 고객관리 및 개별화된 커뮤니케이션이 중요 (중략)

• Proceedings of the Korea Database Society Conference
• /
• 2001.06a
• /
• pp.213-234
• /
• 2001

1. Brokat Server Technologies (Channel 통합 Messging Server) 복잡한 메시지 교환을 유연하게 제어함으로써 Front-End/Back-End각각에 존재하는 다양한 채널을 RealTime으로, 유연하게 통합관리하여 채널간의 Messaging을 Smart하게 컨트롤 2. Brokat Advisor (Rulebase Management System) 복잡한 비즈니스 룰의 적용과 Non-Programming/다이나믹한 관리를 동시에 가능하게 하는 Large E Business Engine (중략)