• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.1090-1097
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• 1999

the multi computers operated in harsh environments should be designed to guarantee normal operations in the presence of the component faults. One solution for this is a fault-tolerant routing. In the paper, we consider n-dimensional meshed network for the basic topology and propose a simple fault-tolerant routing algorithm that can transfer messages to their destination as desired in the presence of some component faults. the built algorithms basically adopts a WormHole(WH) routing method and uses the virtual channels sharing a physical channel for deadlock-freedom. Consequently, we show that the suggested algorithm has a higher performance than the X-Y routing algorithm through simulation results.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.922-925
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• 2004

Bluetooth technology is essentially a method for wireless connection of a diverse set of devices ranging from PDAs, mobile phone, notebook computers, to another equipments. The bluetooth system supports both point-to-point connection and point-to-multipoint connections. In point-to-multipoint connection, the channel is shared among several bluetooth devices. Two or more devices sharing the same channel form a piconet. There is one master device and up to seven active slave devices in a piconet. The radio operates in the unlicensed 2.45GHz ISM band. This allows users who travel world-wide to use bluetooth equipments anywhere. Since the link is based on frequency-hop spread spectrum, multiple channels can exist at the same time. The Bluetooth standard has been suggested that Bluetooth equipments can be used in the short-range, maximum 100 meters . It has been defined that the time takes to setup and establish a bluetooth connection among devices is 10 seconds. It is a long time and may be a cause to lose a chance of finding other non-fixed devices. We propose a routing protocols for scatternets which can be used to control a mobile units(MUs) in this network. The proposed routing protocol is composed of two kinds of bluetooth information, access point(AP) and MU.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.11
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• pp.1052-1057
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• 2004

Bluetooth technology is essentially a method for wireless connectivity of a diverse set of devices ranging from PDAs, mobile phone, notebook computers, to another equipments, The bluetooth system both point-to point connection and point-to multipoint connection. In point-to multipoint connection, the channel is shared among several bluetooth devices. Two or more devices sharing the same channel form a piconet. There one master device and up to seven active slave devices in a piconet. The radio operates in the unlicensed 2.45GHz ISM band. This allows users who travel world-wide to use bluetooth equipments anywhere. Since the link is based on frequency-hop spread spectrum, multiple channels can exist at the same time. The bluetooth standard ha s been suggested that bluetooth equipments can be used in the short-range, maximum 100 meters. It has been defined that the time takes to setup and establish a bluetooth connection among devices is 10 seconds. It is a long time and may be a cause to lose a chance of finding other non-fixed devices. We propose a routing protocols for scatternets which can be used to control a mobile units(MUs) in this network. The proposed routing protocol is composed of two kinds of bluetooth information, access point(AP) and MU.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8B
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• pp.1421-1425
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• 1999

A restoration scheme is presented when a failure occurs at nodes or links on the ATM network. Each node on the network contains the same topology information for resources on the network by Exchanging NSE(Network State Element) which has the network state information through RCC(Routing Control Channel). We also propose a new establishing algorithm that set up a new alternate path reflecting the state of the network changed dynamically at the source node. In the result of applying our scheme, the rates of restoration can be improved and the number of messages decreased so that fast recovering could be possible by reducing traffics on the network by lowering the rates of the call-setup failure at the stage of CAC(Connection Admission Control).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1077-1082
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• 2009

Wireless Mesh Network(WMN) is wireless backbone networks technique which has ease of network configuration and cost of advantage. Recently, WNM released a new product, but most of existing research and technology analysis the performance through the simulation. This paper build the wireless mesh network testbed for actual situation. Testbed supports multi-channel multi-interface using bridge, the Wireless Distribution System and dynamic location-based routing protocol. This routing protocol strongly design against wireless interference using metric for link channel change and real distance. Then, the address of mesh clients assigned by the centralized address management server. Mesh clients is designed and implemented to manage network through Simple Network Management Protocol.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.65-70
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• 2013

In this paper, we propose a multi-hop cooperative transmission protocol to obtain energy savings in static wireless networks. Each terminal in the network is equipped with a single antenna and each receiver uses equal gain combining technique (EGC) to combine received signals. We also propose a power allocation strategy which optimizes the total transmit power at each stage. Monte-Carlo simulations are presented to evaluate and compare performance of the proposed protocol with the multi-hop direct transmission (MDT) and the cooperative routing protocol proposed by Khadani [8], in terms of the average total transmit power and the average number of required stages.

• Water for future
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• v.22 no.4
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• pp.453-461
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• 1989

The analytical diffusion model is first formulated and its characteristics are critically reviewed. The flood events during the 1986-1988 flood seasons i the IHP Pyungchang Representative Basin are routed by this model and are compared with those by the kinematic wave model. The results showed that the analytical diffusion model simulates the observed flood events much better than the analytical kinematic wave model. The present model is proven to be an excellent means of taking the backwater effect due to lateral inflow or down river stage variations into consideration in channel routing of flood flows. It also requires much less effort and computing time at a desired station compared to any other reliable flood routing methods.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.1314-1315
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• 2008

Recent research work has unearthed that multi-radio multi-channel wireless mesh networks offer considerable capacity gains over single-radio wireless mesh networks. In this paper, we present a new routing metric for multi-radio multi-channel wireless mesh networks. The goal of the metric is to choose multiple link/node disjoint paths between a source and destination node that, when used concomitantly, impart high end-to-end throughput. The proposed metric selects high fidelity paths that will produce elevated throughput with maximum fault tolerance.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.733-734
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• 2008

In wireless multihop networks, most of on demand routing protocols suffer from performance degradation due to high mobility and channel errors. This problem is more serious as routing path increases. In this paper, we propose a new scheme which can improve network throughput by using distance adaptive packet bursting. The bursting mechanism is to transmit multiple packets after channel acquisition. Through the simulation, we show that our scheme is more efficient than existing methods.

• 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.