• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.452-464
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• 2015

This paper proposes a DC microgrid operational strategy and control method for improved service reliability. The objective is to supply power to as many non-critical loads as possible, while providing an uninterrupted power supply to critical loads. The DC bus signaling method, in which DC voltage is an information carrier, is employed to implement the operational strategy in a decentralized manner. During grid-connected operation, a grid-tied converter balances the power of the microgrid by controlling the DC voltage. All loads are connected to the microgrid, and operate normally. During islanded operation, distributed generators (DGs), a backup generator, or an energy storage system balances the power. However, some non-critical loads may be disconnected from the microgrid to ensure the uninterrupted power supply to critical loads. For enhanced service reliability, disconnected loads can be automatically reconnected if certain conditions are satisfied. Control rules are proposed for all devices, and detailed microgrid operational modes and transition conditions are then discussed. Additionally, methods to determine control parameter settings are proposed. PSCAD/EMTDC simulation results demonstrate the performance and effectiveness of the proposed operational strategy and control method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.6 no.1
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• pp.13-24
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• 1986

A real-time hourly operation model for the flood control of Soyanggang Dam and Hwachon Dam, which are located in the North Han River is developed. The method is based on simulation with a feedforward-feedback control. The feedforward control was mainly concerned with providing the release history from the single dams. The outflows from the single dam operation rules with forecasted inflows were used as the inputs to simulation. And then feedback control is applied to reduce the peak discharge at the junction. Also, sensitivity analysis of the operation model was provided to respect the temporal and spatial distribution of storms to the model.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.2
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• pp.44-55
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• 1994

This paper describes the development of real-time irrigation reservoir operation models that adequately allocate available water resources for paddy rice irrigation. Water requirement deficiency index(WRDI) was proposed as a guide to evaluate the operational performance of release schemes by comparing accumulated differences between daily release requirements for irrigated areas and actual release amounts. Seven reservoir release rules were developed, which are constant release rate method (CRR), mean storage curve method(MSC), frequency analysis method of reservoir storage rate(FAS), storage requirement curve method(SRC), constant optimal storage rate method (COS), ten-day optimal storage rate method(TOS), and release optimization method(ROM). Long-term forecasting reservoir operation model(LFROM) was formulated to find an optimal release scheme which minimizes WRDIs with long-term weather generation. Rainfall sequences, rainfall amount, and evaporation amount throughout the growing season were to be forecasted and the results used as an input for the model. And short-term forecasting reservoir operation model(SFROM) was developed to find an optimal release scheme which minimizes WRDIs with short-term weather forecasts. The model uses rainfall sequences forecasted by the weather service, and uses rainfall and evaporation amounts generated according to rainfall sequences.

• Journal of the Korea Society for Simulation
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• v.26 no.3
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• pp.125-139
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• 2017

Recently, interest in improving the quality of EMS(emergency medical services) has been increasing. Much effort is being made to innovate the EMS process. The rapid progress of ICT technology has accelerated the automation or intelligence of EMS processes. This study suggests an emergency room management method based on real-time data considering resource utilization optimization, minimization of human error and enhancement of predictability of medical care. Emergency room operation indices - Emergency care index, Short stay index, Human error inducing index, Waiting patience index - are developed. And emergency room operation rules based on these indices are presented. Simulation was performed on a virtual emergency room to verify the effectiveness of the proposed operating rule. Simulation results showed excellent performance in terms of length of stay.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06c
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• pp.351-357
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• 1994

At least two projects for English-to-Korean translation have been already in action for the last few years, but so far no attention has been paid to the problem of resolving pronominal reference and a default pronoun translation has been considered instead. In this paper we argue that pronous cannot be handled trivially in an English-to-Korean translation and one cannot bypass the task of resolving anaphoric reference if aiming at good and natural translation. In addition, we propose lexical transfer rules for English-to-Korean anaphor translation and outline an anaphora resolution model for an English-to-Korean MT system in operation.

• Journal of the military operations research society of Korea
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• v.17 no.2
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• pp.90-99
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• 1991

In this paper a dispatching rule, $D^{*}$, for AGV operations in automated manufacturing system is proposed to improve the performance measures. And the algorithm is compared with existing heuristic rules via simulation to evaluate its capabilities. It is shown that the proposed rule enhances mean flow time, makespan and throughput, and avoids the locking phenominon which can be fatal to the operation of automated manufacturing systems.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.03a
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• pp.109-117
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• 1994

This paper describes a method and a system for automatic generation of flanged cylinderical deep drawing process outlines. A process outline is a sequence of operation leading from the blank to the required finished part. The input is the dimension of final product and the output is the effective process outline to manufacture the product. That system is programmed by PROLOG language and is composed of facts and rules of manufacturing knowledge hierarchically.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.228-232
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• 1993

This paper describes a on-line monitoring and fault diagnosis system designed for the automation of a medium-size concrete plant. The system is based on the structure of a hardware system of data acquisition and a personal computer. Simulation results are presented to illustrate the system operation. It applies the preconstructed rules to the plant data for the diagnosis of weighing processes.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.3-5
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• 2009

A study has the status of a basic safety publication in accordance with the principles given in IEC Guide 104 and ISO/IEC Guide 51. Provides general rules for the use of certain colours or numerals to identify conductors with the aim of avoiding ambiguity and ensuring safe operation.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.583-586
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• 1995

In this paper, a nor fuzzy control algorithm for the target tracking system is proposed, and its characteristics are analyzed and compared with those of the traditional PID controller. Fuzzy rules are generated experimentally using Mamdani's minimum operation and the center of area method. The experimental results prove that the proposed fuzzy algorithm is excellent in our tracking system and its performance is superior to that of the PID controller.