• Journal of KIISE:Information Networking
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• v.29 no.5
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• pp.459-465
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• 2002

Ad-hoc networks have the dynamic topology characteristics and most of the applications on ad-hoc networks require the group communication capability. Previously proposed multicast mechanisms on mobile ad-hoc networks build multicast-infrastructures like the tree or mesh for the group communication and these infrastructures nay cause significant overhead especially in a highly dynamic mobile ad-hoc network environment. Therefore, in this paper, we propose a new multicast mechanism supporting multicast services based on only the underlying unicast routing tables, hence any multicast-related infrastructures like trees and meshes are not required to be constructed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.593-600
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• 2007

In this paper, we composed several road network and evaluated the network for the performance of the network with protocols. The protocols we applied were the MANET routing protocols such as AODV(Ad-hoc On-Demand Distance Vector) and DSR(Dynamic Source Routing) protocols. Generally, the AODV performs better than the DSR. However, in my ad-hoc vehicular network, the performance of the DSR is the better than the AODV when there are more vehicles in the road environment than there are the less vehicles. For the simulation, we composed 4-lane road with vehicles and simulated in the OPNET.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04a
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• pp.868-870
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• 2004

ad-hoc 망에서 라우팅 프로토콜의 부하균등(load balancing)은 이동성과 전송 지연사이의 trade-off로 인하여 성능 관점에서 중요한 이슈가 되어왔다. 부하균등을 고려한 SLAP(Simple Load-balancing Ad-hoc routing Protocol)이 제안되었으나 혼잡이 발생하거나 망의 토폴로지가 변화하였을 때 유연하게 대처하지 못한다. 본 논문에서는 ad-hoc 망에서 트래픽 혼잡 제어와 망의 이동성에 적응하기 위하여 동적인 임계치를 사용하는 부하균등 라우팅 프로토콜을 제안하였다. 제안된 프로토콜은 성능은 GloMoSim으로 시뮬레이션을 수행하여 AODV, DSR, SLAP과 지연, 패킷 전송률 등을 비교하여 평가하였다.

• International Journal of Contents
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• v.5 no.2
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• pp.43-52
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• 2009

The article first presents a broad overview of the design and management for survivable network. We review the concept of network survivability, various protection and restoration schemes. Also we introduce design architectures of Quantitative model and a Survivable Ad hoc and Mesh Network Architecture. In the other side of study like these(traditional engineering approach), there is the concept of the survivable network systems based on an immune approach. There is one sample of the dynamic multi-routing algorithms in this paper.

• Korean Journal of Hydrosciences
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• v.2
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• pp.69-84
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• 1991

US NWS/NETWORK is applied for the analysis of the flood of July 11-15, 1981 through the Goan-Indogyo reach of the Han River. For the flood hydrography synthesis of the lateral inflows from the major tributaries into the main reach the Cleak method is employed. NETWORK coupled with the Clark method of hydrography synthesis simulated with a fair accuracy the oberved flood hydrograph at the downstream boundary of the routing reach. The dffect of SCS runoff curve number for fributary flood synthesis is evaluated. The characteristics of the station variations and time variations of the flood discharges in the reach is also analyzed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.10 s.113
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• pp.985-992
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• 2006

The classic routing algorithms try to minimize the number of hops to reach a destination. In our DPC(Distributed Power Control) this hop-by-hop power level selection is also used to select the path guaranteeing low energy consumption. The main goal is to realize a dynamic protocol able to be aware of mobility and to automatically set security threshold in order to get the best performance in every situation. In conclusion, the simulation DPC has improved energy gain of the AMRIS routing algorithm at the narrow area, and ODMRP routing algorithm has improved energy gain at the wide area.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.2
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• pp.271-287
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• 2013

We propose a new multipath-based reliable routing protocol on MANETs, Multipath-based Reliable routing protocol with Fast-Recovery of failures (MRFR). For reliable message transmission, MRFR tries to find the most reliable path between a source and a destination considering the end-to-end packet reception reliability of the routes. The established path consists of a primary path that is used to transmit messages, and the secondary paths that are used to recover the path when detecting failures on the primary path. After establishing the path, the source transmits messages through the primary path. If a node detects a link failure during message transmission, it can recover the path locally by switching from the primary to the secondary path. By allowing the intermediate nodes to locally recover the route failure, the proposed protocol can handle the dynamic topological change of the MANETs efficiently. The simulation result using the QualNet simulator shows that the MRFR protocol performs better than other protocols in terms of the end-to-end message delivery ratio and fault-tolerance capability.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.4
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• pp.2020-2037
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• 2017

In order to improve the energy efficiency of n-Epidemic routing protocol in opportunistic networks, in which a stable end-to-end forwarding path usually does not exist, a novel adjustment strategy for parameter n is proposed using learning atuomata principle. First, nodes dynamically update the average energy level of current environment while moving around. Second, nodes with lower energy level relative to their neighbors take larger n avoiding energy consumption during message replications and vice versa. Third, nodes will only replicate messages to their neighbors when the number of neighbors reaches or exceeds the threshold n. Thus the number of message transmissions is reduced and energy is conserved accordingly. The simulation results show that, n-Epidemic routing protocol with the proposed adjustment method can efficiently reduce and balance energy consumption. Furthermore, the key metric of delivery ratio is improved compared with the original n-Epidemic routing protocol. Obviously the proposed scheme prolongs the network life time because of the equilibrium of energy consumption among nodes.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.1 s.343
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• pp.71-78
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• 2006

MANET routing protocols must support not only wireless networking without any relaying on network infrastructure, but also dynamic management of routing information caused by node mobility. Hence, they are one of important routing protocols for USN. Recently DYMO is regarded as a promising routing protocol for UMT because it is simple and easy to extend as well as it requires less networking load than others. In this paper, we design and implement DYMO routing protocol into various operation systems. Also, we develop a DYMO conformance test tool to evaluate our implementations.

• Water for future
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• v.27 no.1
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• pp.141-150
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• 1994

The purpose of this study is develope the algorithm of channel routing model which can be used for flood forecasting. In routing model, the hydrulic technique of the implicit scheme in the dynamic equation is chosen to route the unsteady varied flow. The channel routing model is connected with conceptual watershed model which is able to compute the flood hydrograph from each subbasin. The comparative study shows that the conceptual model can simulate the watershed runoff accurately. As a result of investigating the channel routing model, the optimal weighting factor $\theta$ which fixes two points between time line is selected. And also, the optimal error tolerance which satisfies computing time and converge of solution is chosen.