• 전기학회논문지
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• 제61권6호
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• pp.910-915
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• 2012

In this paper we propose multi-grounded neutral design method which was considered of transferred transient overvoltage when line to neutral fault occurs. Specially, In order to confirm the actual transient overvoltage magnitude which occurs on neutral line, we considered some screening(shielding) effects. The screening coefficient was deducted from field test results and calculation in a distribution line which is identical with an actual power line. The purpose of this paper is to attempt to suggest the guidance for grounding skystem design considering limitation of overvoltage for LV side in IEC 61936. The result is based on EMTP simulation and real field faults situation in distribution lines.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.243-244
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• 2015

Power system has been improved during for a long time by customers demand. Power suppliers has researched the power system component for more electricity transmission. One of the research is apply the thermal conductors in new cable. The operational temperature of thermal conductors is higher than normal aluminum that thermal conductor is composed of aluminum, Zr(zirconium) and etc. Increase of operational temperature is growth of the transmission capability. Power suppliers was concerned about the increase of operation temperature by thermal conductors. Therefore, the thermal conductor has the possibility that expanded application in power system. In this paper analysed effect of thermal conductor in power distribution system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.453-453
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• 2000

This paper presented Fuzzy logic application to Electrical power system analysis for fault location estimation in distribution lines and apply the Power system theory to be fuzzy logic database. The case study referred to the Overhead distribution line of the Provincial Electricity Authority (PEA.), Thailand which mostly the distribution line of PEA. are Radial schemes. These benefits include reduced outage time, help in locating momentary faults, enhance safety to the line crews and provide notification of an outage without receiving calls from the consumer, Which these benefits also increase Reliability, Stability and Efficiency.

• 천문학회보
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• 제36권2호
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• pp.83.2-83.2
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• 2011

The emergence of a magnetic flux tube (flux emergence) is a process of transporting magnetic field from the solar interior to the atmosphere. This process naturally produces bipolar structure at the surface, in which emerging field lines simply connect opposite polarities, while observations suggest that the surface distribution of magnetic field is more complicated than a simple bipole. This study is aimed at solving this apparent mismatch between the model and observations, showing how the surface distribution changes from a simple bipolar distribution to a quadrupolar-like one, where a half-turn rotation of the polarity inversion line plays an important role. We explain the physical reason of this half-turn rotation and also discuss a possible configuration of filament magnetic field in terms of the quadrupolar-like structure formed via flux emergence.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권4호
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• pp.246-251
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• 2003

This paper proposes a new methodology for the estimation of impedance characteristics, which is one of the important issue in the power distribution network design of printed circuit boards. The modeling process of the proposed method divides the power distribution network into uniform segment, and each segment is modeled by distributed RLC transmission lines. Then, for the efficient computation of impedance characteristics in frequency domain. the proposed method uses a model-order reduction method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.813-815
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• 1997

최근의 전력품질은 양적인 요구에서 질적인 요구로 변화하고 순간적인 전압강하나 정전이 사회에 미치는 영향이 크게 되었다. 배전선로 신뢰도 향상을 통한 안정적 전력공급을 위해 조류고장 방지에 대한 대책을 지금까지 다양한 방법으로 시도하였으나 조류고장은 여전히 중가추세에 있다. 조류고장 원인을 분석하면 길조로 인식되고 있고 자연한경보호 의식이 고조되면서 까치수가 급증하고 지역개발에 의해 교목이 감소하면서 전주애 둥지를 짓고 둥지재료도 나무가지 및 철선을 이용하여 둥지재료와 전선과의 접촉으로 전선단선동 고장복구에 장시간을 요하게 된다. 조류피해 방지대책의 종류와 시행상 문제점을 분석하고 까치집을 철거하지 않고 까치와 공존 공생할 수 있는 환경 신화적이고 과학적인 배전설비 구축으로 조류고장의 근원적 해소로 양질의 전력공급에 최선을 다하고자 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.234-239
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• 2004

A study on the probabilistic methodology for the estimation of the remaining life of Pressurized pipelines containing active corrosion defects is presented. This reliability assessment is earned out using extream value distribution of the corroded defects instead of already published failure perssure moded like NG18 or ASME B31G. The failure probability of pipelines depends on the number of corroded defects. and it could be calculated directly as the area exceeded a defined L V(Limited Value of corrosion depth). The remaining life of pressurized pipelines can also be estimated by the PDF of extream value distribution as calculating the exceeded area with a defined failure probability.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.399-401
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• 2000

Recently polymer insulators are being used for outdoor high voltage applications. Polymer insulators for transmission and distribution line have significant advantages over porcelain and glass insulators, especially for ultra-high voltage(UHV) transmission lines. Their advantages are light weight, vandalism resistance and hydrophobicity. In this paper, polymer line post insulator has been designed and investigated electric field distribution by FEM. Designed LP insulators have been tested as insulator performance test, such as power frequency voltage test, lightning impulse voltage test, artificial pollution test and flexural load test.

• 한국전기전자재료학회논문지
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• 제29권1호
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• pp.58-61
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• 2016

Degradation in power cables used in distribution lines to the material of the wire, manufacturing method, but also the line of the environment, generates a variety of degradation depending upon the type of load. The local wire deterioration weighted wire breakage accident can occur frequently, causing significant proprietary damage can lead to accidents and precious. In this study, the signal detected by the eddy current aim to develop algorithms capable of determining the signals for the top part and at least part of the signal by using a signal processing technique called K-means algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기설비전문위원
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• pp.183-185
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• 2004

Despite high cost, the underground power distribution system has been preferred by utilities and customers due to its stability and good living environment. Utilities, however, are burdened with the cost of installation as the service region of underground power system is getting enlarged. In this paper, a design method is proposed in order to reduce the construction cost of underground distribution system. That is an optimum algorithm, which can increase the total number of pipes in a limited space compared with a conventional design method. As a result, the proposed design method can reduce efficiently the construction cost of underground distribution system.