• Journal of Korea Water Resources Association
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• v.37 no.6
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• pp.487-497
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• 2004

Adding important new projects such as reservoirs which regulate a river discharge to a river system, existing operation methods should be changed considering these conditions. Since an original operation rule used for an existing system has been designed to be compatible to inputs and outputs of the existing system, the operation rule should be changed to consider the new projects. In this study, the technique of constructing new operation rules considering objectives of both old and new projects is suggested when new project is added to the river system. Reservoir operation rule using both stochastic inflow and optimization technique is developed. As a result of applying the technique to Geum river basin, the efficiency of the technique is verified.

• Journal of Korea Water Resources Association
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• v.40 no.11
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• pp.877-886
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• 2007

An urban drainage system consists of two major systems : flood drainage facilities and operating practices. The facilities are composed of sewer networks, gates, and pumping stations and the operating practice consists of pump or gate operation. Then, a real time simulation system which is able to simulate urban runoff and the pump operation and to consider the backwater effect is required to operate efficiently the pump. With this system, the efficient pump operating rule can be developed to diminish the possible flood damage on urban areas. In this study, a real time simulation system was developed using the SWMM 5.0 DLL and Visual Basic 6.0 equipped with EXCEL. Also, for developing efficient pump operating Rules, two new Rules were suggested. The first Rule is designed to operate pumps considering the condition of sewer networks such as depths of each junction. The second is to discharge all the amount of inflow at each time step. Results obtained by those Rules were compared with one by the current pump operating Rule which is able to consider only the depth of the retard basin. The developed model was applied to Joonggok retard basin and verified their applicability.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1176-1181
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• 2006

The purpose of this study was to estimate water supply analysis and reliability indicators by using allocation rule(AR) about Andong Dam and Imha Dam which have parallel reservoirs system. According to the analysis results of allocation rule, for Rule(A) and Rule(B), the contribution of water supply in Andong Dam was 60% more than in Imha Dam, and for Rule(C), the contributions in Andong Dam and Imha Dam were almost equal. In Rule(C), supply is allocated by the ratio which divides the sum of storage and inflow by the mean storage according to the storage state and supply capability state of Andong Dam and Imha Dam. This Rule(C) showed good results in the water supply capability analysis and reliability analysis of parallel reservoirs. In the analysis criteria of water supply in parallel reservoirs system, monthly water change quantity showed better results than monthly constant water quantity in water supply analysis. On the basis of this study, the new technique for water supply analysis was developed to be applied to parallel reservoirs, and this operation rule will establish the efficient operation measures in the application to several kinds of parallel reservoirs system.

• Journal of Korea Water Resources Association
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• v.47 no.10
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• pp.891-906
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• 2014

This study suggests the hedging rule of MIP (Mixed Integer Programing) in counting the risk evaluation criteria of the objective function and constraints in order to provide the optimum operating rule in reservoir system as constraining water shortage as much as possible which may happen in the downstream control point of water supply in the aspect of water system management. The proposed model is applied to the Han-river reservoir system for two testing periods (Case I: Jan. 1993~Dec. 1997, Case II: Jan. 1999~Dec. 2003). The model based on the hedging rule with trigger volume, estimated in this study shows that in Case I, the monthly minimum discharge was $310.6{\times}10^6m^3$ in the single operation, $56.3{\times}10^6m^3$ in the joint operation, and $317.5{\times}10^6m^3$ in the hedging rule and also, in Case II, the monthly minimum discharge was found to be $204.2{\times}10^6m^3$ in the single operation, $111.2{\times}10^6m^3$ in the joint operation, and $243.7{\times}10^6m^3$ in the hedging rule. In conclusion, the hedging rule, proposed in this study can decrease vulnerability while guarantees reliability and resiliency.

• Journal of Korea Water Resources Association
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• v.30 no.3
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• pp.269-278
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• 1997

Operating rules, the basic principle of reservoir operation, are mostly developed from maximum or minimum, mean inflow series so that those rules cannot be used in practical operating situations to estimate the expected benefits or provide the operating policies for uncertainty conditions. Many operating rules based on the deterministic method that considers all operation variables including inflows as known variables can not reflect to uncertainties of inflow variations. Explicit operating rules can be developed for improving the weakness. In this method, stochastic trend of inflow series, one of the reservoir operation variables, can be directly method, the stochastic technique was applied to develop reservoir operating rule. In this study, stochastic dynamic programming using the concepts was applied to develop optimal operating rule for the Chungju reservoir system. The developed operating rules are regarded as a practical usage because the operating policy is following up the basic concept of Lag-1 Markov except for flood season. This method can provide reservoir operating rule using the previous stage's inflow and the current stage's beginning storage when the current stage's inflow cannot be predicted properly.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.1
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• pp.99-108
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• 1991

Rapid changes of urban hydrologic events need new management operation rule of detention reservoir which is essential outflow control system in urban area. Therefore, this study is to develop the outflow management method of Seoul city considering the Han river flood characteristics, to analyze the inundation of detention reservoir according to variation of design storm patterns, and to examine the safety of gate due to design flood water level. From this study, new operation rule is presented. The design storm patterns are determined by instantaneous intensity method and Huff's quartile method. And the inflow hydrograph of detention reservoir is obtained by applying ILLUDAS model and RRL method. The operation rule of existing drainage pump is designed to have linear relation between storage and pumping discharge. But in this study, it is effective for preventing inundation when the operation rule of drainage pump have Gaussian function which is combined the storage of detention reservoir with its inflow according to increasing or decreasing of inflow hydrograph.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.61-61
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• 2011

하천에서의 홍수 피해 발생을 예방하기 위한 대책은 크게 구조적인 대책과 비구조적인 대책으로 나눌 수 있다. 구조적인 대책은 댐이나 제방과 같이 하천을 중심으로 수공구조물을 설치하여 직접적인 홍수 발생을 억제하는 대책이지만, 비구조적인 대책은 무형의 체계를 통해 하천에서의 홍수발생을 억제하는 대책이다. 비구조적인 대책 가운데 대표적인 것이 홍수 예 경보인데, 한강홍수통제소에서는 1974년부터 홍수 예 경보시스템을 구축하여 운영하고 있다. 본 연구에서는 남한강 유역에 대한 홍수 방어능력 검토와 홍수 방어대책 강구에 필요한 충주 댐 수문 운영이 가능한 수리학적 홍수추적 모형을 구축하였으며, 충주댐을 중심으로 상 하류 구간에서 수위증가를 억제하기 위한 수문 운영기법을 검토하고자 하였다. 이를 위해 남한강 상류에 위치한 영월2 수위관측소로부터 팔당댐까지의 대상구간에 대해 최근 이루어진 하도측량자료를 이용하여 수리학적 모형을 구축하였다. 구축된 모형에 대해 2006년 홍수사상을 적용하여 모형의 보정을 실시하였으며, 2003년부터 2008년까지의 홍수사상을 대항으로 검증을 실시하였다. 충주댐 수문 운영은 HEC-RAS 모형 내의 E.C.G(Elevation Controlled Gate) 기법과 Rule Operation 기법을 이용하여 남한강 주요 지점에서의 홍수의 증가에 대한 억제효과를 검토하였다.

• Journal of KIISE:Databases
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• v.29 no.1
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• pp.1-14
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• 2002

Association rule discovery is a method of mining for the associated item set on large databases based on support and confidence threshold. The discovered association rules can be applied to the marketing pattern analysis in E-commerce, large shopping mall and so on. The association rule discovery makes multiple scan over the database storing large transaction data, thus, the algorithm requiring very high overhead might not be useful in real-time association rule discovery in dynamic environment. Therefore this paper proposes an active candidate set management model based on trigger and incremental update mechanism to overcome non-realtime limitation of association rule discovery. In order to implement the proposed model, we not only describe an implementation model for incremental updating operation, but also evaluate the performance characteristics of this model through the experiment.

• Journal of Digital Contents Society
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• v.2 no.2
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• pp.103-115
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• 2001

This paper proposes the two algorithms which generate a minimal decision rule and approximate inference operation, adapted the rough set and the factor space theory in fuzzy knowledge base. The generation of the minimal decision rule is executed by the data classification technique and reduct applying the correlation analysis and the Bayesian theorem related attribute factors. To retrieve the specific object, this paper proposes the approximate inference method defining the membership function and the combination operation of t-norm in the minimal knowledge base composed of decision rule. We compare the suggested algorithms with the other retrieval theories such as possibility theory, factor space theory, Max-Min, Max-product and Max-average composition operations through the simulation generating the object numbers and the attribute values randomly as the memory size grows. With the result of the comparison, we prove that the suggested algorithm technique is faster than the previous ones to retrieve the object in access time.

• Water for future
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• v.19 no.4
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• pp.339-346
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• 1986

A real-time single reservoir operation model using the Min-max Dynamic Programming for the flood control of Soyanggang Dam and Choongju Dam is developed. The objective function is to minimize the maximum release from each dam and the constraints are those from ther reservoir and channel characteristics. Control and utilization efficiencies are used to measure the performance of the reservoir operation method (ROM). In comparison with those of simulation models(such as the Rigid ROM, the Technical ROM and the Linear Decision Rule), the efficiencies of the optimization model are superior for all return periods.