• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.5B
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• pp.762-770
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• 2010

The researches about energy efficieny of wireless sensor MAC protocol is an issue in present days. Therefore, MAC and routing protocols for reducing energy consumption at sensor nodes is needed. In this study, a low-power MAC protocol for sensor network is proposed, which in based on X-MAC by exploiting virtual synchronization. The virtual synchronization technique lets senders postpone packet transmission until receivers' wake-up time, so that senders transmit only one or two short preambles. Using NS-2, a proposed MAC protocol improve the energy efficiency by 10% compared with the X-MAC protocol.

• Water for future
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• v.27 no.4
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• pp.95-104
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• 1994

The sinuosity model has been developed to simulate to developed to simulate the floodwave in meandering channels by solving the extended Saint-Venant equation with the Preissmann scheme. The suggested model is compared with three conventional floodplain routing methods in terms of governing equations, mass conservation error and floodwave analysis. The sinuosity model produces the mass conservation error of 1.5-1.8%, however the separate channel model produces 9.1% and 27.4% for sinuosity of 1.5 and 2.0, respectively. The model has been used to simulate flow in an idealized meandering river with a floodplain. The attenuation ratio and the travel time ratio are found to increase as the floodplain roughness and width increase and as the sinuosity factor decreases. The model is expected to contribute the floodwave analysis in sinuous channel with compound corss sections.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.4
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• pp.121-127
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• 2011

Many peer-to-peer (p2p) systems have been studied in distributed, ubiquitous computing environments. Distributed hash table (DHT)-based p2p systems can improve load-balancing even though locality utilization and user mobility are not guaranteed. We propose a mobile locality-based hierarchical p2p overlay network (MLH-Net) to address locality problems without any other services. MLH-Net utilizes mobility features in a mobile environment. MLH-Net is constructed as two layers, an upper layer formed with super-nodes and a lower layer formed with normal-nodes. Because super-nodes can share advertisements, we can guarantee physical locality utilization between a requestor and a target during any discovery process. To overcome a node failure, we propose a simple recovery mechanism. The simulation results demonstrate that MLH-Net can decrease discovery routing hops by 15% compared with JXTA and 66% compared with Chord.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.6
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• pp.1187-1193
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• 2003

The interest for IPv6, which is next generation IP, increases, while the difficulty for adopting it into IT industries also increases too. We also expect that Internet technologies develop on basis of All-IP networks, which include various heterogeneous networks. Therefore, it is necessary for network to support mobility and multicast capability to create applications with wide-variety. In this paper, we propose a new mobile multicasting protocol called Mobile IPv6 Multicast Protocol(MIMP). The proposed scheme satisfies no packet losses from roaming and optimal routing efficiency.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.77-83
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• 2010

Vehicular Ad Hoc Networks are self-organizing Peer-to-Peer networks that typically have highly mobile vehicle nodes, moving at high speeds, very short-lasting and unstable communication links. VANETs are formed without fixed infrastructure, central administration, and dedicated routing equipment, and network nodes are mobile, joining and leaving the network over time. So, VANET-security is very vulnerable for the intrusion of malicious and misbehaving nodes in the network, since VANETs are mostly open networks, allowing everyone connect, without centralized control. In this paper, we propose a rough set based anomaly detection method that efficiently identify malicious behavior of vehicle node activities in these VANETs, and the performance of a proposed scheme is evaluated by a simulation in terms of anomaly detection rate and false alarm rate for the threshold ${\epsilon}$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.6
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• pp.528-534
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• 2013

The energy consumption problem should be taken into consideration in wireless sensor network. Many studies have been proposed to address the energy consumption and delay problem. In this paper, we propose BISA(Bio-inspired Scheduling Algorithm) to reduce the energy consumption and delay in wireless sensor networks based on biological system. BISA investigates energy-efficient routing path and minimizes the energy consumption and delay using multi-channel for data transmission by multiplexing data transmission path. Through simulation, we confirm that the proposed scheme guarantees the efficient energy consumption and delay requirement.

• Journal of the Korean Society of Marine Environment & Safety
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• v.11 no.2 s.23
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• pp.9-17
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• 2005

In the present maritime traffic conditions of Gwangyang harbor, there exists many hazardous factors which may lead to huge accidents including marine oil pollution. To mitigate the danger to vessels in Gwangyang harbor and to secure the safety of maritime environment, we established one way traffic between No.3 Route and No.4 Route, Designed of deep water line on No.3 route, Extended one-way route for Myo-Do Passage etc.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.5
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• pp.27-36
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• 2004

In this paper, we propose the ethernet Inter-Processor Communication (IPC) network architecture and 10gigabit ethernet frame multiplex/demultiplexer architecture for the edge switch system based on Linux that has 10 Gigabit Ethernet (10Gigabit Ethernet) port with 72Gbps capacities. we discuss the ethernet IPC with ethernet switch and we propose design and implementation of ethernet Inter-Processor Communication (IPC) network architecture and multiple gigabit ethernet frame rnultiplexing/demultiplexing scheme to handle 10gigabit ethernet frame instead of using 10gigabit network processor. And then ethernet Inter-Processor Communication (IPC) network architecture and 10gigabit ethernet frame MUX/DMUX architecture is designed verified and implemented.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.5
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• pp.457-461
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• 2008

Previous studies on overlay ad hoc multi-casting are mainly divided into two categories: hierarchical structure-based multicast schemes and non-hierarchical structure-based multicast schemes. They do not reflect their real-time location information for routing updates. This can be a cause of low performance on energy consumption, throughput, and latency. For improving the problems, we propose an implicit cluster based overlay ad hoc multicast scheme with analysis of related work, and then we evaluate performance through computer simulation.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.895-904
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• 2004

Due to the frequent and unpredictable topology changes, multicast still remains as challenge and no one-size-fits-all protocol could serve all kinds of needs in mobile ad hoc network. In this paper, we propose a novel scheme of Hierarchical Eulerian Ring Oriented Multicast Architecture (HEROMA) over mobile ad hoc network. It has features that concentrate on efficiency and robustness simultaneously. It is also an application-driven proposal for hazard detection. Architectures including Eulerian ring, hierarchy and multicast agent are investigated in detail Simulation results different level of improvements on control traffic, end-to-end delay and packet delivery ratio by comparing with tree-based and mesh-based multicast protocols.