• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2317-2322
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• 2011

In three-phase power, when the power is supplied to the single phase load, there is the unbalance of load in the three-phase power. So the scott transformer is used in the power system to supply a single phase load in three-phase power without the unbalance of loads. Especially, the scott transformer is used in the AC substation of electric railroad. Two single phase transformers are combined by T-wiring in the scott transformer. So, two single phase voltage is provided by differing $90^{\circ}$ phase in three-phase power. The selection of related equipment and correction of protective relay are not easy from characteristic of the scott transformer when shunt and ground faults occur. In this paper, electric model of the scott transformer is suggested and the current of the scott transformer in shunt and ground faults is analyzed. Also, the scott transformer model is demonstrated by using Sinulink.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.246-249
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• 2007

This paper discusses the standards for disaster prevention and safety management of rail tunnel. The purpose is to establish safety management standards and methods of disaster prevention for each underground traffic spaces, after the full revision of the cause of accidents and its effects, the function and selection of safety equipment, and the efficiency and convenience of maintenance, standards based on prevention and reduction is proposed to reaction to disaster.

• Journal of Broadcast Engineering
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• v.1 no.2
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• pp.133-141
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• 1996

In this paper, a VOD(Video -on-Demand) system is implemented using LAN(Local Area Network). The use of LAN causes the time-delay problem due to its narrow channel limitation, as a result, the service using the conventional LAN used not to be popular. In this paper, to solve these problems, we develop the modified topology, the selection methodology of the network equipment, and the dedicated(improved) protocol. Consequently, we can serve at most 3 or 4 clients at the same time, and we conclude it is necessary to optimize the network buffer size depending on the size of video data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.1
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• pp.58-66
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• 2002

Electric power facilities must have effective grounding to provide means to carry electric current into the earth under fault conditions and to prevent damage of equipment, ignition, and electrocution of personnel. This paper resent an algorithm called the Pattern Search method for the optimal parameters selection of the grounding system Simulation results using these parameters obtained from the PS method verify that the grounding systems are adequately designed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.12
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• pp.177-183
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• 2010

Overhead transmission lines in domestic area have been built by several different design standards of dip and ground clearance. This paper describes an experimental study for evaluating load capacity and dip margin in overhead transmission lines. Such design standards for selection of overhead transmission conductors, dip and ground clearance, as well as electrical equipment technical standard are discussed. Based on daily load and weather data, several characteristics such as line utilization factor, load factor, conductor temperature and dip, etc. are analyzed, and compared with the specified levels of design standards. As a result, it is verified that DLR method can be a clue of the solving of the problem, for occurring in old transmission conductors which may be rarely operating below standards.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.11-18
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• 2006

For the more comfortable thermal environment in residential buildings, it was necessary for variable components like as automatic flow limiting valves and/or balancing valves in hydronic system. And, these components had an effect on flow-rate and pressure inside pipe. In this case, the incompatibility between the design for the heating system and the selection of equipment was the causes of several problems in heating pipe network. In this study, we peformed measurements and analyses of flow rate and pressure inside pipe for radiant floor heating in residential buildings through field surveys and experiments in order to find out the actual conditions and problems. On the basis of this, we suggested the approach for the optimal flow-rate and pressure maintaining inside pipe in individual heating system.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.1126-1128
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• 1992

The object of this study is the design of 3 phase on-board inverter. The key point in the inverter design is the selection of switching device, and its performance effects that of total system. In this study, six-step square wave inverter was designed using IGBT ( Insulated Gate Bipolar Transistor ) which has the advantages of MOSFET and bipolar transistor as switching device. The condition of being small and light which is the one of requirements for on-board equipment was accomplished by using IGBT module and optimising the snubber circuit, and the reliablity was increased. It is confirmed that the designed inverter satisfies the required performance through the performance and environment test.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.6
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• pp.395-403
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• 2016

In mobile industry, using a metal frame of devices is rapidly increased for thin and stylish designs. However, fabricating metal is one of the difficult processes because the sophisticated control of equipment is required during the whole machining time. In this study, we present an efficient multivariate monitoring procedure for the metal frame process in mobile device manufacturing. The effectiveness of the proposed procedure is demonstrated by real data from the mobile plant in one of the leading mobile companies in South Korea.

• Annals of Clinical Neurophysiology
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• v.19 no.2
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• pp.113-117
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• 2017

The performance of electroencephalogram (EEG) recordings is affected by electrode type, electronic parameters such as filtering, amplification, signal conversion, data storage; and environmental conditions. However, no single method has been identified for optimal EEG recording quality in all situations. Therefore, we aimed to provide general principles for EEG electrode selection as well as electronic noise reduction, and to present comprehensive information regarding the acquisition of satisfactory EEG signals. The standards provided in this document may be regarded as Korean guidelines for the clinical recording of EEG data. The equipment, types and nomenclature of electrodes, and the details for EEG recording are discussed.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.38-39
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• 2006

KEPCO is executing a project in Cambodia consisting of two components, "Power Development Master Plan and Institutional Strengthening" and "Greater Mekong Sub-region (GMS) Power Project Preparation" upon request by the government of the Ministry of Industry, Mines and Energy of Cambodia, contracted on $29^{th}$ September 2005. This paper includes a basic design and review of economical efficiency for constructing the two (2) cross border 115 kV transmission lines, which run from the border of Vietnam and Laos to Cambodia, and four (4) 115kV substations. The main contents of the paper include the process of design and results of a review of line route selection, tower and hardware design regarding transmission line design, as well as the type of substation, and arrangement and specifications of equipment with expects to substation design. Also, long-term demand forecasting, and an economic analysis of the project area are included.