• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.5
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• pp.688-694
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• 2018

The transition section of the overhead rigid conductor rail (ORCR) consists of a direct induction device and a limit point to prevent the power supply failure and failure of the electric railway vehicle pantograph due to the difference of the uplift in the catenary line. In T-Bar transition section, a twin simple catenary is mostly installed between the overhead catenary system (OCS) in the ground section and the ORCR in the underground section. In this paper, we compare and analyze the possibility of replacing the twin simple catenary with heavy simple catenary. The reliability of numerical analysis results was confirmed by comparing field test with numerical results. Comparing the numerical results of the twin simple catenary with the heavy simple catenary in the transition section, the difference uplift is 5.9[mm] on average. When applying heavy simple catenary instead of twin simple catenary, the slight difference of uplift can be compensated by adjusting the height of hanger-ear or support bracket.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.113-115
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• 2005

전력케이블, 특히 지중 송전케이블은 사고 발생시 그 파급효과가 크기 때문에 빠르고 정확한 고장점의 탐지가 필요하다. 본 논문에서는 on-line으로 지중 케이블의 상태를 모니터링하면서 사고 발생시에는 기록된 데이터를 분석하여 고장점을 찾을 수 있도록 하는 고장점 탐지 장치 개발에 관하여 언급한다. 케이블의 고장점 탐색 기술 개발을 위하여 단락 사고를 모의할 수 있는 모의 고장 발생 시스템을 구성하여 인위적인 고장발생을 할 수 있도록 하였으며 고장시 발생하는 신호를 측정하여 측정된 신호로부터 고장 발생 지점을 보다 정확하게 찾아내는 신호처리 기술을 연구하였다. 본 연구를 통하여 개발된 고장점 탐색장치는 정밀하게 사고지점을 찾아낼 수 있음을 보여주었으며 실제 전력 공급 계통에 손쉽게 설치할 수 있는 장점을 가지고 있다. 이하에 송전선 고장점 위치 계산을 위하여 개발된 고장점 탐색 기술에 관하여 언급한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.248-248
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• 2007

Demands for electricity are growing, whereas the rate of electricity infrastructure's construction declines gradually. To keep the balance of the demand and supply, the share of underground transmission line will be increased from 8.3% to 10.5% in 2020 but it will be accompanied with enormous public expenses. A great concern in high capacity transmission is on the increase so as to maximize the spacial efficiency. High Temperature Superconducting (HTS) cable is in the lime light which has the merits of environment-friendly, low transmission loss and high transmission with low voltage, but the reliability verification as a power system is yet to be solved. KEPCO completed the installation and acceptance of $3{\phi}$, 22.9kV, 1250A class HTS cable system in 2006 and the long term test is in progress. The test results focusing on long term reliability are presented in this paper.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.4
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• pp.263-273
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• 2019

South Korea's OF cable is reaching its expected design life of 30 years, and as a result, the risk of failure is increasing. Therefore, it is necessary to diagnose the long-term operating OF cables through accurate diagnosis at the right time to prevent the failure. Currently, the KEPCO periodically conducts DGA. However, the gas found in DGA is caused by oil deterioration as well as insulation paper. Therefore, the analysis of the degree of polymerization and furan compounds which is an evaluation of insulation paper considered to be the life of OF cables is required. In addition, the results of the evaluation of deterioration of insulation paper need to be checked for correlation with the results of DGA. In this study, DGA carried out through GC, the degree of polymerization was analyzed using an automatic viscometer, and HPLC was used to detect the furan compounds. In addition, the obtained results were applied to the SVM technique, which was recently introduced to determine abnormalities in OF cable. And the results which were accurate and reliable were obtained.

• Journal of Environmental Impact Assessment
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• v.23 no.5
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• pp.353-363
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• 2014

The purpose of this study was to investigated the ELF-MF emission level of various environments such as 258 facilities near located to high voltage transmission lines and 120 high voltage transmission lines, 17 underground cable lines. In addition, ELF-MF reduction rate according to separation distance was calculated by using simulations. An appropriate separation distance showing below 4mG was at least 70m. In the case of the appropriate separation distance for 120 high voltage transmission lines, 154kV required 20m of separation distance and 345kV required 60m of separation distance. The simulation results showed that the appropriate separation distance showing below 4mG was 40m and 60m for overhead 154kV and 345kV respectively. To adjust the worst conditions considering the aspects of environmental impact assessment study and the electric power currents that will increase in the future, the appropriate minimum separation distance for HVTL is judged to be above 70m in this study. Thus, there is a need to establish the greenbelt or buffer zone within 70m so as to create an environment in which the receptors are not exposed and thereby eliminate the risk factors of ELF-MF against humans.

• Journal of the Korean Regional Science Association
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• v.14 no.1
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• pp.91-107
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• 1998

Waste disposal problem is one of the most important social welfare indicators in urban area, because the volume of waste generated from urban area is remarkable. So far most waste of Seoul has been disposed at landfills. However, this landifill disposal method is confronted with several difficulties in recent. As public concern on environmental problem increases and autonomy system is settled down, local community people of the landfills refuse to receive the waste produced other places any more. It brought reginal confliction problem between waste sending and receiving by refusing to accept waste from certain region. Furthermore, it is difficult to find another place to fill up the waste, while the existing landfiis is reached at the limit in the near future. In terms of environmental aspects landfill method is not the best way to dispose waste. It contaminates the soil and ground/underground water by leaking water containing many serious pollutants as well as offensive oder. In terms of equity, this waste disposal method is not fair. Environmental pollution causes damage to residence near to the landfills, while the waste produced other places. In order to satisfy the equity aspect, the waste generated a region should be disposed within the region. Incineration of Waste has been provided as the alternative. Government plans to construct waste incinerator in every anatomy, so the waste produced by local community is disposed within their local autonomous area. However, the location decision is not easy, since waste incinerator is one of the facilities to the community people. We can not apply the existing location models for this problem, because they show strong NIMBY phenomenon for the location. The location of waste incinerator should be determined very carefully with consideration of various location factors and criteria. This study proposes a methodology for determining the location of the waste incinerators by utilizing GIS, which is a power research tool for location decision where various geographical factors related. We drive the location factors which should be considered in the determination of waste incinerators. They involve environmental, socio-economic, and institutional factors. In first, we eliminate the area which is located within the environmental location criteria such as slope, fault line, distance to river, and then eliminate ares which is conflict with the social and institutional criteria.