• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.410-412
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• 2011

Magnetic cables that can deliver high frequency AC electric power safely for flammable or sensitive workplaces preventing from arcs and electric shocks are firstly proposed in this paper. To deliver the power for a long distance, several new magnetic cable structures which drastically reduce the parallel leakage flux by appropriate magnetic shield between the magnetic cables are suggested; hence, the output power can be improved more than ten times. The proposed magnetic cables are fully analyzed and verified by simulations and experiments with good agreement. The output power and efficiency for a prototype magnetic cable of 1.5m long and 1 cm gap between parallel cores were measured as 154W and 67 %, where the source current and frequency were 10 A and 20 kHz, respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.812-814
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• 1993

During the last two decades, we experienced a few of the energy shocks and felt the importance of the energy saving seriously. As our energy reliance on other countries is absolute. We must counter these situations nationally. To save the electric energy, various methods are explored such as the moderation of motor capability, the use of high efficiency system, the supervision of lighting systems, demand monitoring control systems. In this study, we develop a system for electric power energy saving. In Case the receiving point voltage is higher than the required voltage, the system reduce the voltage to an allowable level and by doing so it saves energy and protects the equipments from over voltage.

• 한국정보통신학회논문지
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• 제10권4호
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• pp.724-730
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• 2006

접지저항은 접지의 성능을 결정하는 기초요소이다. 접지는 낙뢰, 원치 않는 과도전류 및 과도전압의 유입, 그리고 전기적 잡음으로부터 시스템을 안정적으로 동작하게 할뿐만 아니라 전기적 충격으로부터 인명을 보호하는 것을 접지의 목적으로 하고 있다. 국내의 경우 이러한 접지기술에 대한 기술기준으로 정해진 고시가 있으나 내용이 매우 제한되어 있기 때문에 현실성이 결여되어 있다. 따라서 통신설비를 시설 하는데 있어 많은 문제점을 초래한다. 본 논문에서는 이러한 문제점을 개선하기 위한 방법으로 접지저항에 대한 실측을 통해서 나온 결과치를 참고자료로 제공하고자 한다.

• 융합정보논문지
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• 제12권2호
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• pp.127-133
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• 2022

ITO와 CNT를 적용한 전극을 코팅하여 제작한 대전입자형 전자종이 디스플레이 패널을 제작하여 내구성 및 전기광학적 특성을 비교한다. ITO 전극의 면저항은 10(ohm/sq.)이고 CNT 전극의 면저항은 300, 600, 1000(ohm/sq.)이며 내구성 측정을 위하여 물리적 충격 및 유연성 측정을 진행한다. ITO 전극의 경우 40회의 충격과 10mm의 곡률 반지름에서부터 변화가 시작되나 CNT 전극에서는 변화가 측정되지 않는다. 입자 이동, 반사율 및 응답 시간 측정에 필요한 구동 전압, 전계 등 전기광학 측정결과 CNT 전극은 ITO 전극과 유사한 결과를 얻었다.

• 한국안전학회지
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• 제35권2호
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• pp.61-66
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• 2020

As asbestos-containing buildings are getting older, asbestos deconstruction works are increasing. As a result, accident risks such as falls, cuts, electric shocks, and suffocation are increasing. Existing studies are mostly about health management and institutional policy research and there is little research on work risk. So workplace risk assessments that are easily applicable in the field are required to be applied. Sealing is the first process of asbestos deconstruction and is the first step to ensure worker's safety. Job Safety Analysis(JSA) and Checklist were used to identify the risk factors and to calculate the level of the risk. By comparing the two risk assessment tools, it was figured out that the JSA is appropriate for the initial process and change of work procedure while Checklist is appropriate for repetitive work. Because the sealing process is sort and simple, it is unlikely to cause serious injury. But since the risk of falling and cuts are exist, safety education and supervision are necessary to maintain a safe working environment.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.495-498
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• 2001

The distribution line through which electricity is supplied from substation to customer generally varies by underground line and overhead line. In contrast that the underground line is shielded, the overhead lines do not have the shield layer. To overcome this weak point of the overhead lines, the aerial bundled cable(ABC) connection systems have been developed. The basic concept of the ABC connection system is the application of the underground cable system containing complete shield layer to the overhead cable system. The ABC system is the innovative technologies which enable the prevention of electric shocks, reduction of the maintenance charge and damage of the cable. This paper give a full detail of vertical connection system applied within a country.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.724-729
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• 2005

Winter weather condition can cause icing and ice coats on 25 kV overhead contact wire. This generates shocks at the mechanical interface of the collecting strips of the pantograph and the contact wire and extra electrical resistance, which may affect quality of current collection at the contact wire / collecting strips of pantograph interface. De-icing operations should he performed just before train operation to avoid the formation of another ice layer. Thus, the work in this paper is investigation and analysis of de-icing system which could be applied to the electric car line of railways.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기설비전문위원
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• pp.5-7
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• 2005

When 345 kV transmission lines began to be operated in 1976,electrostatic shocks were problems due to high electric field. By reducing the electirc field below 3.5 kV/m, the problems were solved. But recently a transmission line route.is proposed, nearby people strongly object to build the line worrying abour the effect of magnetic field,even though they do not really know the megnetic effect. Some environmentalists insists to reduce to reduce the magnetis field to a few mG near the transmission line. So we have studied the mitigation method to reduce magnetic field by two conductor passive loop.

• Journal of Advanced Marine Engineering and Technology
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• 제35권8호
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• pp.1117-1123
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• 2011

비접지 배전방식이 채택되는 선박은 일선지락 상황에서도 정전사고로 이어지지 않으므로 상대적으로 안정적인 급전이 가능하다. 그러나 비접지 계통에서 발생하는 지락고장은 대지 전압을 왜곡시켜 선체에 대한 선로 전압을 상승시키므로 감전사고와 전기화재의 위험이 높아진다. 특히 선로와 선체 간에 작용하는 분포용량은 대지임피던스의 한 요소로서 지락고장 시 대지전압의 왜곡 특성에 큰 영향을 미친다. 이 같은 대지전압의 변화는 3상 대지전압 중성점의 이동에 의해 설명될 수 있다는 점에서 본 연구에서는 대지임피던스를 입력으로 할 때 대지전압을 출력으로 하는 연산모듈을 구성한 후 이를 이용하여 접지저항 변화에 대응하는 대지전압 중성점의 이동 경로 특성을 확인하였다. 또한 다양한 조건에서 나타나는 중성점 이동경로를 구하는 한편 실제 배전계통에서의 측정 결과와 비교함으로써 제시된 분석방법의 적정성을 나타내었다.

• Animal cells and systems
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• 제7권4호
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• pp.303-307
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• 2003

The aim of this study is to investigate whether alcohol alters learning and memory processes pertaining to emotional and spatial factors using the active avoidance and T-maze task in zebrafish. In the active avoidance task, zebrafish were trained to escape from one compartment to another to avoid electric shocks (unconditioned stimulus) following a conditioned light signal. Acquisition of active avoidance task appeared to be normal in zebrafish that were treated with 1% alcohol for 30 min for 17 days until the end of the behavioral test, and retention ability of learned behavior, tested 2 days later, was the same as control group. In the T-maze task, the time to find a reservoir was compared. While the latency was similar during the 1 st training session between control and alcohol-treated zebrafish, it was significantly longer in alcohol-treated zebrafish during retention test 24 h later. Furthermore, when alcohol was treated 30 min after 2nd session without prior treatment, zebrafish demonstrated similar retention ability compared to control. These results suggest that chronic alcohol treatment alters spatial learning of zebrafish, but not emotional learning.