• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.202-203
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• 2005

• Proceedings of the Korea Water Resources Association Conference
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• 2003.05b
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• pp.847-850
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• 2003

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.432-436
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• 2009

Recently, damage of flood is increased because of a short of time of concentration by development and a rise in runoff discharge by frequently heavy rain. The increase of runoff discharge is resulted in not only rise of water level but also damage of lives and property around river. Therefore, it is should be the first to estimate the exact runoff discharge. And based on the estimated flood discharge, flood damage is prevented by estimating inundated area of flood. In this study, flood stage is forecasted using HEC-HMS and HEC-RAS for Namdae-stream. The peak discharges were determinated by probability rainfall with the return period. The peak discharges obtained from HEC-HMS were inputted boundary conditions for the channel routing. Flood stages were evaluated using HEC-RAS.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.449-453
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• 2007

Has been being operated since 1974, recently, the flood forecasting and warning system is applied in almost all the rivers in Korea, and the Storage Function Method(SFM) is used for flood routing. The SFM which was presented by Toshimitsu Kimura(1961) routes floods in channels and basins with the storage function as the basic equation. A watershed is devided into two zone, runoff and percolation area and Runoff is occured when cumulated rainfall is not exceed saturation rainfall, but exceed, runoff is occured from percolation area, too. Runoff area is given and not changed, runoff ratio is constant. In routing process, runoff from runoff and percolation area is routed seperately with nonlinear cenceptual reservior having same characteristics and it is unreasonable assumption. Modified SFM is proposed with storage function and continuity Equation which has no assumption for routing process and effective rainfall is calculated by SCS Method. For Wi Stream, comparision of Kimura and Modified SFM is conducted and It could be seen that Modified SFM is more improvemental and easily applicable method.

• Journal of Korea Water Resources Association
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• v.40 no.7
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• pp.523-532
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• 2007

It has been operated since 1974, recently, the flood forecasting and warning system is applied in almost all the rivers in Korea, and the Storage Function Method (SFM) is used for flood routing. The SFM which was presented by Toshimitsu Kimura (1961) routes floods in channels and basins with the storage function as the basic equation. A watershed is divided into two zone, runoff and percolation area and runoff from runoff area is occurred when cumulated rainfall is not exceed saturation point, but exceed runoff is occurred from percolation area, too. Runoff area is given and not changed, runoff ratio is constant. In routing Process, runoff from runoff and percolation area is routed seperately with nonlinear conceptual reservoir having the same characteristics and it is unreasonable assumption. A modified SFM is proposed with storage function and continuity equation which has no assumption for routing process and effective rainfall is calculated by SCS Method. For Wi-stream, comparison of Kimura and the modified SFM is conducted, and it could be seen that the modified SFM is more improvable and applicable method easily by reducing the parameters.

• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.787-796
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• 2002

Hydraulic flood routing was performed for unsteady flow in a natural river using Preissmann scheme. A Log-Pearson Type-Ⅲ hydrograph is chosen arbitrarily as the upstream boundary condition and lateral inflow hydrographs for sensitivity analysis. For the application with an actual river system, upstream and lateral inflow hydrographs were estimated by the linear reservoir model and the Manning's equation was used as the downstream boundary condition. The unsteady flow model using the linear reservoir model as the inflow hydrographs was applied to Bochung stream basin and gives good results, and is approved to be used for the runoff prediction. As results of the sensitivity analysis, the proposed model may help to estimate the roughness coefficients when using the unsteady flow model with lateral inflow combined with the linear reservoir model.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.74-79
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• 2001

A one-dimensional flood routing model was formulated to simulate the flood flow of drainage sub-canal using the continuity equation of paddy field and the momentum and continuity equation of drainage sub-canal. The model was applied for evaluating the hydraulic characteristics of drainage sub-canal at large-sized paddy fields. The model applicability was evaluated with field data and the simulated results were in good agreement with the observed data.

• Journal of Environmental Science International
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• v.14 no.11
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• pp.995-1004
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• 2005

As a research establish reservoir safety operation for small dam systems. This study presents hydrologic analysis conducted in the Duckdong and Bomun dam watershed based on various rainfall data and increase inflow. Especially the Duckdong dam without flood control feature are widely exposed to the risk of flooding, thus it is constructed emergency gate at present. In this study reservoir routing program was simulation for basin runoff estimating using HEC-HMS model, the model simulation the reservoir condition of emergency Sate with and without. At the reservoir analysis results is the Duckdong dam average storage decrease $20\%$ with emergency gate than without emergency gate. Also, the Bomun dam is not affected by the Duckdong flood control augmentation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4644-4661
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• 2015

Wireless sensor networks are often organized in the form of clusters leading to the new framework of WSN called cluster or hierarchical WSN where each cluster head is responsible for its own cluster and its members. These hierarchical WSN are prone to various routing layer attacks such as Black hole, Gray hole, Sybil, Wormhole, Flooding etc. These routing layer attacks try to spoof, falsify or drop the packets during the packet routing process. They may even flood the network with unwanted data packets. If one cluster head is captured and made malicious, the entire cluster member nodes beneath the cluster get affected. On the other hand if the cluster member nodes are malicious, due to the broadcast wireless communication between all the source nodes it can disrupt the entire cluster functions. Thereby a scheme which can detect both the malicious cluster member and cluster head is the current need. Abnormal energy consumption of nodes is used to identify the malicious activity. To serve this purpose a learning based energy prediction algorithm is proposed. Thus a two level energy prediction based intrusion detection scheme to detect the malicious cluster head and cluster member is proposed and simulations were carried out using NS2-Mannasim framework. Simulation results achieved good detection ratio and less false positive.

• ETRI Journal
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• v.43 no.4
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• pp.674-683
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• 2021

A trust-aware secure routing protocol (TSRP) for wireless sensor networks is proposed in this paper to defend against varieties of attacks. First, each node calculates the comprehensive trust values of its neighbors based on direct trust value, indirect trust value, volatilization factor, and residual energy to defend against black hole, selective forwarding, wormhole, hello flood, and sinkhole attacks. Second, any source node that needs to send data forwards a routing request packet to its neighbors in multi-path mode, and this continues until the sink at the end is reached. Finally, the sink finds the optimal path based on the path's comprehensive trust values, transmission distance, and hop count by analyzing the received packets. Simulation results show that TSRP has lower network latency, smaller packet loss rate, and lower average network energy consumption than ad hoc on-demand distance vector routing and trust based secure routing protocol.