• 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.

• Journal of Korea Water Resources Association
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• v.46 no.12
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• pp.1141-1155
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• 2013

A number of studies have been performed to analyze climate change impacts of water resources system. In this study, a coordinated dam operation is compared with an existing operation strategy for coping with projected future runoff scenarios. GCMs (Global Circulation Models) and the LARS-WG downscaling method was used to project future climate scenarios. The water balance model called abcd was employed to estimate future runoff scenarios. The existing dam operation comes from the national dam construction guideline, which is called the "level-operation method." The alternative coordinated dam operation are constructed as a linear programming using New York City rule for refill and drawdown seasons. The results of annual total inflow in future is projected to decrease to 72.81% for Andong dam basin and 65.65% for Imha dam basin. As a result of applying future runoff scenarios into the dam operation model, the reliability of coordinated dam operation, 62.22%, is higher than the reliability of single dam operation, 46.55%. Especially, the difference gets larger as the reliability is low because of lack of water. Therefore, the coordinated operation in the Andong & Imha dams are identified as more appropriate alternative than the existing single operation to respond to water-level change caused by climate change.

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.5
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• pp.37-49
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• 2023

The drought risk has been increasing recently due to climate change causing the extreme climate to be more frequent. In order to supply agricultural water stably under drought, it is necessary to operate an agricultural reservoir in response to drought. To this end, it is crucial to establish appropriate drought response operation rules considering weather conditions and reservoir status. In the reservoir operation simulation, the supply amount differs from the actual reservoir supply for many reasons, including maintaining water levels for supply and accommodating farmers' requests. So, for a more realistic reservoir operation simulation, it is necessary to reflect the reservoir operation rules of the actual water management site. Therefore, in this study, through a survey, the standards for limitation of agricultural water supply applied to agricultural reservoirs in Korea were investigated, and the criteria for drought response reservoir operation (DRO) were established based on the survey. Then, the DRO was applied to the irrigation period for nine subject reservoirs. The applicability was evaluated by comparing the DRO result to the operation result of HOMWRS (Hydrological Operation Model for Water Resources System). The reservoir drought index, storage rate, and daily supply were compared for evaluation. From the result, DRO showed more stable operation results in most cases against drought as it has fewer days of water supply limitation and a somewhat reservoir storage rate which can be utilized for prolonged drought.

• Journal of Arbitration Studies
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• v.19 no.3
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• pp.179-198
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• 2009

This paper aims at assessing reasonableness for restraining the independence principle in the operation of documentary credit in case of the illegality appeared in the underlying transactions. It has been a major rule under the independence principle to keep the credit operation free from the defences made by the issuing bank and/or credit applicant with a view to prevent the payment as specified under the credit. And also, it is generally accepted in the international commercial community to examine a presentation to determine, on the basis of the document alone, whether or not the documents appear on their face to constitute a complying presentation. Even though these two essences are major rules in the credit operation, if a presentation is made with the documents forged or materially fraudulent, the issuing bank can refuse to pay the documents in respect of fraud rule based on fraud exception for which a court of appropriate jurisdiction would enjoin such honour. Now we have newly come to another situation to determine whether or not we have to apply the same as fraud rule which is applicable to the illegality in the underlying contract under the new conception of illegality principle based on illegality exception. English Commercial Court handled the illegality case under the case of Mahonia Ltd., v. JP Morgan Chase Bank in 2003 and Justice Colman decided that issuing bank can rely on illegality affecting a letter of credit as an excuse for failure to pay. This judgement brought about the acceptance of illegality principle based on illegality exception as a defence to payment under a letter of credit as far as the illegality concerned in the underlying transactions. It is noticeable that this case will affect our international commercial community more to rely on the illegality in the underlying transactions as a good issue to stop payment for the issuing bank in the L/C operation.

• 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.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.2875-2888
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• 1999

In this paper we present compiler-based active rule system to efficiently maintain spatial integrity constraints in a heterogeneous, distributed environment. Specially, the prototype active rule system presented has been developed as a component of a whole middleware system called SDBC(Spatile DataBase Connectivity). Due to this reason, our active rule system is provided for heterogeneous ODBMSs in a distributed environment and used to define spatial integrity constraints using the active rules in E-C-A(Event-Condition-Action) type. Using this active rule system, an application programmer can free himself from a heavier burden on the integrity maintenance of application objects. In the compiler-based approach, active rules applicable to events raised by a database program are directly inserted into the program in a function type by the preprocessor, and then they are compiled with the application program source codes. One advantage of this approach is that there is no run-time overhead accompanied by monitoring all the database transitions when preprocessed program is executed. This active rule system also provides facilities to manage changed rules and dynamically interpret those rules at run-tuime.

• Journal of Korea Port Economic Association
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• v.27 no.1
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• pp.137-154
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• 2011

This study is to contribute to create favorable conditions for developing the new port in a timely and as well helps to propose role and establish status of incheon port in the future by reviewing port facility capacity of Incheon Newport, applied trigger rule reasonably. By applying trigger rule with annual growth rate(11.4%) between 2001 to 2009 rules it will be 18 berths reducing 2 years for completion date than annual growth rate(9.4%) forecasted by Ministry of Land, Transport and Maritime Affairs. This paper first suggests the tri-ports policies including Incheon new port, Busan port and Gwang-Yang port and creating favorable conditions for the early completion and lastly attracting high valued-added transshipment cargo for developing incheon new port in a timely.

• Journal of IKEEE
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• v.24 no.2
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• pp.610-618
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• 2020

This paper presents the modeling of hybrid railway vehicles with hydrogen Fuel-Cells (FCs)/battery using a rule-based algorithm. The driving power of traction system is determined with the speed-torque curve by operation area of the electric machine and the electrical systems are modeled. The demanded power of electrical systems is set with the energy management system (EMS). The consumption of hydrogen is effectively managed with the subdivided operation region depending on the state of charge (SOC). The validity of the modeling is verified using MATLAB/Simulink.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.8
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• pp.648-658
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• 1990

There are many methods for speed up counting in speech recongition. A multiple processing method is the one way to achieve the aim using systolic array. This arithmetic operation by the array is achieved pipelining skill. And the operation is multiprocessing by processing element(PE) that is incresing counting efficiencies. The DTW PE cell is seperated into three large blocks. "MIN" is the one block for counting accumulated minimum distance, "ADD" block calculated these minimum distances, and "ABS" seeks for the absolut values to the total sum of local distances. We have accomplished circuit design and verification about the "ADD" and "ABS" blocks, and performed total layout '||'&'||' DRC(design rule check) using 3um CMOS N-Well rule base.le check) using 3$\mu$m CMOS N-Well rule base.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.3
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• pp.212-216
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• 2002

A practical issue is studied to improve the performance of a new energy based method of achieving stable, high performance haptic interface control. The issue is related to resetting the amount of energy accumulated in the Passivity Observer for faster operation. A heuristic method is derived and experimentally tested for the resetting and it is shown to help the PC to operate sooner when the system gets active. Experimental results are presented for the “Excalibur” haptic device.