• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.307-308
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• 1987

A low-Pressure gap decoupling crow-bar switch was designed and operated to obtain prolonged current pulses by discharging 50kJ condeser banks. And air core Rogowski coil was used for measuring high current.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.769-770
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• 1988

The Pockel's effect is well know as a voltage measurement method. This method is applicable to high voltage measurement equipments. We observe the Faraday rotation of the polarization plane in the current-induced magnetic field.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.397-398
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• 1988

We report on the simulation results of 1)the second harmonic conversion with $1.053{\mu}m$ Nd:glass laser using monolithic KDP crystal and 2)the efficient conversion from $1.053{\mu}m$ to $0.35{\mu}m$ by the polarization-mismatch 3rd harmonic conversion in two Type-II crystals.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2385-2387
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• 2002

종래 도로상의 차량검지기들은 기후변화 및 도로환경의 변화, 물리적인 변화에 영향을 받아 감지의 정확도가 떨어져 신뢰도 높은 교통정보를 생성하기가 어렵고, 제품의 가격이 고가이며, 설치 및 유지, 보수에 많은 비용과 인력이 요구된다. 본 연구에서는 종래의 차량 검지기가 지니는 문제점들을 해결하여 어떠한 환경하에서도 신뢰성 있는 차량 주행정보를 제공하며 동시에 유지, 보수 비용이 저렴한 검지기로서 AMR(Anisotropic Magneto-Resistive) 센서를 이용하여 도로상의 차량 이동에 따른 지구자기장(Earth Magnetic Field) 변화를 감지하고 차량의 이동상태를 파악하는 교통량 계측장치를 제시한다.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1568-1570
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• 1994

Laser-triggered-lightning is protection methed for power apparatus against lightning. It is necessary to understand the generation mechanism of laser produced plasma. So production of long distance laser-plasma-channel was numerically analyzed with electron growth equation and laser transport equation.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.731-733
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• 1987

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.1
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• pp.1-7
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• 2017

Concrete behavior in early-age is changing due to hydration reaction with time, and a resistance to chloride attack and strength development are different characterized. In the present work, changing strength and resistance to chloride attack are evaluated with ages from 28 days to 6 months. For the purpose, strength, diffusion coefficient, and passed charge are evaluated for normal concrete with 3 different mix proportions considering 28-day and 6-month curing conditions. With increasing concrete age, the changing ratio of strength falls on the level of 135.3~138.3%, while diffusion coefficient and passed charge shows 41.8%~51.1% and 53.6%~70.0%, respectively. The results of chloride diffusion coefficient and passed charge show relatively similar changing ratios since they are much dependent on the chloride migration velocity in electrical field. The changing ratios in chloride behaviors are evaluated to be much larger than those in compressive strength since the ion transport mechanism is proportional to not porosity but square of porosity.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.580-581
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• 2011

국내의 지중케이블 시스템은 1970년대 154kV급 OF케이블이 도입된 이래로 현재까지 345kV급 OF/XLPE 케이블을 이용한 지중송전선로가 운영 중에 있으며, 도심지역의 전력공급을 위해 지중송전선로의 건설비중이 점차 증가하고 있다. 그러나 지중송전 계통에서 고장발생시 사회적 파장이 크고 가공송전선로에 비교할 때 복구에 대단히 많은 시간과 비용이 소요되므로 설비의 안전운전 및 장기신뢰성의 확보가 반드시 필요하다. 따라서 지중송전계통의 현장 조건을 고려한 실증시험장 구축의 필요성이 대두되어, 한국전력공사에서 정부의 인프라구축 지원사업으로 초고압 지중케이블에 대한 국제품질 공신력 확보 및 최적운영기술을 확보하기 위하여 장기 신뢰성 시험이 가능한 설비와 국제적 규모의 실증시험장을 구축하였다. 아울러 2011년 3월에는 ISO/IEC 17025에 따른 국제공인시험기관 자격을 취득하여, 국내외에서 제작되는 초고압 케이블에 대한 국제 공인시험이 가능하게 되었다. 따라서 본 논문에서는 한국전력공사 고창전력시험센터 내에 구축된 지중케이블 시험장 및 장기신뢰성 시험설비에 대한 소개와 더불어 국제표준에 따른 공인시험방안과 현재까지 지중케이블 시험장에서 수행된 케이블 시험에 대하여 소개하고자 한다.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.613-618
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• 2019

EMF (Electromagnetic Field) is a valuable resource for living in a knowledge-based information society. The EMF is used in home appliances that make our lives easy and convenient, and in telecommunication devices such as mobile phones, personal computers, medical devices and broadcasting towers. However, the biological hazards associated with EMF exposure are also increasing in signal from telecommunication devices. Studies of the effects of EMF exposure on humans have been conducted for a long time, but it has not yet been demonstrated whether the EMF effect is harmful. In this paper, we examine the electromagnetic field emitted from various electronic devices around living and its effect.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.1
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• pp.132-140
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• 2009

For human exposure assessment of UHF RFID system, electric field distribution of commercial 900[MHz] RFID antenna was measured and analyzed. Also, SAR(Specific Absorption Rate) of RFID antenna was calculated by simulation, and compared with basic restrictions in EMF guidelines. For EMF exposure assessment according to EN and IEC standards, the reader was tested for the normal operation, and electric field from RFID antenna was measured at various distances and angles. For electric field measurement, narrow band isotropic electric field probe was used, and the measurements were made at 0.3, 0.5, 1.0 and 1.5[m] for every 15[$^{\circ}$] angle from the antenna. Also, the rationale for measurement distance in EN and IEC standards is analyzed from the measurement results.