• 제목/요약/키워드: electric

검색결과 33,411건 처리시간 0.054초

이온화방사선 피폭에 의한 골수세포의 Ornithine Decarboxylase 활성도의 변화에 대한 전계장의 영향에 관한 실험적 연구 (An Experimental Study on the Effect of Electric Field the Ornithine Decarboxylase Activity Change of Myeloid Cells According to Ionizing Radiation Exposure)

  • 정문호
    • 한국환경보건학회지
    • /
    • 제21권1호
    • /
    • pp.78-85
    • /
    • 1995
  • Ornithine decarboxylase(ODC) is an indicate enzyme in carcinogenesis. We divided Sprague Dawley rats into six groups: control, electric field exposure, X-ray only irradiation, X-ray irradiation with electric field exposure group, Sr-90 injected group and Sr-90 and electric field complex exposure group. The ODC activity was measured in rat's bone marrow cell every week. The results were summarized as follows: The ODC activitied was increased in X-ray irradiated, Sr-90 injected and Sr-90 and electric field complex exposed group as compared with that of control(p<0.05). The ODC activity was increased comparing that of control neither in X-ray and electric field complex exposed group nor electric field only exposed group. This result suggests that the electric field doesn't have myeloid carcinogenicity and myeloid cancer incidence caused by ionized radiation is suppressed by electric field exposure.

  • PDF

UHF 부분방전 신호를 이용한 전력용 변압기 내부의 부분방전 위치 추정 (Localization of partial discharge in power transformer by detecting UHF PD signal)

  • 주형준;구선근;한기선;박기준;윤진열
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2008년도 제39회 하계학술대회
    • /
    • pp.147-148
    • /
    • 2008
  • In this paper two kinds of techniques were compared for localization of PD(partial discharge) in power transformer and more useful method was suggested. Both of them, the time of arrival and the energy content method, were tested in 154kV single phase experimental transformer using UHF signal measurement. The former was using the difference of arrival time of recorded signals from four UHF sensors, the latter was based on the energy content in frequency spectra of signals detected at all sensors.

  • PDF

Electrical Fire Hazards Analysis of Electric Iron and Heater Using Fault Tree Analysis

  • Hong, Sung-Ho
    • International Journal of Safety
    • /
    • 제7권1호
    • /
    • pp.15-20
    • /
    • 2008
  • The primary goal of this study is to analyze fire hazards of electric home appliances such as electric iron and electric heater using fault tree analysis(FTA). A fault tree(FT) is constructed and used to analyze fire hazards in electric home appliances. The fault tree is built from events that may occur in electric home appliances. The failure rate of basic events are derived from the value of experimental results and reference. And an algorithm analyzing fire in electric home appliances is suggested. We show how fault tree analysis, carried out by means of failure rate, is able to diagnose fire hazards of electric home appliances in a precise manner. We present numerical results such as fire probability of electric home appliances, importance measure, fire cause, etc. It can be helpful in preventing the fire hazards in electric home appliances.

병렬 하이브리드 전기자동차의 주요 구성시스템에 대한 상대적 가격 모델링 (Relative Cost Modeling for Main Component Systems fo Parallel Hybrid Electric Vehicle)

  • 김필수;김용
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
    • /
    • 제48권6호
    • /
    • pp.294-300
    • /
    • 1999
  • There is a growing interest in hybrid electric vehicles due to environmental concerns. Recent efforts are directed toward developing an improved main component systems for the hybrid electric vehicle applications. Soon after the introduction of electric starter for internal combustion engine early this century, despite being energy efficient and nonpolluting, electric vehicle lost the battle completly to internal combustion engine due to its limited range and inferior performance. Hybrid Electric vehicles offer the most promising solutions to reduce the emission of vehicles. This paper describes a method for cost reduction estimation of parallel hybrid electric vehicle. We used a cost reduction structure that consisted of five major subsystems (three-type and two-type motor) for parallel hybrid electric vehicle. Especially, we estimated the potential for cost reductions in parallel hybrid electric vehicle as a function of time using the learning curve. Also, we estimated the potentials of cost by depreciation.

  • PDF

국내외 전기자동차 기술 개발 동향 및 국내 전기자동차 핵심 부품 기술 개발 전략 (Technology Development Trend of Domestic and Foreign Electric Vehicle and Technology Development Strategy of Domestic Electric Vehicle Core Parts)

  • 손영욱;허건수
    • 전력전자학회논문지
    • /
    • 제22권5호
    • /
    • pp.373-381
    • /
    • 2017
  • The electric vehicle market has increased rapidly in recent years. Established global automakers have announced that electric cars will be developed and distributed. Furthermore, current electric cars are not merely breezes, instead, they are the mainstream of automobiles. However, high prices, short mileage, and long charge times are the main obstacles to the spread of electric vehicles. To solve these problems, the competition for technology development for the expansion of electric vehicles worldwide intensifies because of the improvements in mileage, price reduction, and expansion of charging infrastructure. In this paper, the trends in the development of key technologies for electric vehicles in overseas markets and the present strategic goals for the development of key technologies for electric vehicles in Korea will be identified.

변전설비 용량기준의 합리화 방안 및 대책에 관한 연구 (A Study on the Reasonable Design Standard and Countermeasures of the Demand Factor)

  • 유현재;하복남;남궁도;박상만;조남훈
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1996년도 하계학술대회 논문집 B
    • /
    • pp.902-904
    • /
    • 1996
  • In this paper, we proposed the reasonable design standard and countermeasures of Demand Factor for large office buildings, that was made by the statistical way considering actual conditions, such as investicated electric equipment capacity, electric power consumption, etc. So as to save electric equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electric rates, we can be contributed by the application of the design standard. The result of saving effect is showed to confirm the practical use of the proposed Demand Factor, and also, it is believed that this proposed Demand Factor will be useful in electric equipment operation and planning.

  • PDF

가로등설비 누전시 건조상태와 침수상태에 대한 전위분포 분석 (The Analysis on the Electric Potential Distribution of Dry and Submerged Condition by Electric Leakage in Street Lamp)

  • 홍성호;박상태;김상철
    • 한국안전학회지
    • /
    • 제23권6호
    • /
    • pp.44-50
    • /
    • 2008
  • This paper presents study on the electric potential distribution when have a short in street lamp. In order to measure electric potential testing ground is built in. A experiment is conducted to simulate dry and submerged situation of street lamp. The street lamp is leaked by artificial means. And electric potential is measured in grounded street lamp and street lamp alone. The results show that touch voltage of grounded street lamp is possible more high than street lamp alone. And the electric shock hazard is high because high electric potential is distributed near submerged street lamp. Also if street lamp is submerged ground is not useful to decrease electric shock hazard.

온라인 전기 자동차를 위한 급전 및 집전 시스템

  • 정구호;이경훈;김형국;조양진;송보윤;손영동;박은하;최주영;공병오;허진;손호섭;조정구;임춘택;전성즙
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2010년도 하계학술대회 논문집
    • /
    • pp.218-219
    • /
    • 2010
  • 온라인 전기자동차는 도로에 매설된 급전선로로부터 유도자계를 통하여 비접촉 방식으로 전기를 집전 받아 정차 및 주행 중에 충전하는 자동차이다. 이러한 비접촉 충전을 위해서는 도로에 매설된 급전 시스템과 차량 하부에 장착된 집전 시스템이 필요하며, 급전 시스템은 다시 급전 인버터와 급전선로로, 집전 시스템은 집전 모듈(pick-up)과 집전 레귤레이터로 구성된다. 본 논문에서는 급집전 시스템 각각의 장치를 소개하며, 더불어 구축된 시스템의 성능에 대해서도 소개한다.

  • PDF

A Study of Servitization Strategy for Electric Vehicles

  • Lee, Sang-Hyun
    • 유통과학연구
    • /
    • 제14권9호
    • /
    • pp.5-13
    • /
    • 2016
  • Purpose - This study proposes a framework for service innovation strategy to cope with the emergence of electric vehicles. Research design, data, and methodology - This study designs an electric-vehicle lease program and collects the resulting data to analyze. By analyzing the previous studies on the electric-vehicle market with cases, a theoretical framework based on existing theories is to be set. Results - This study proposes a strategy for the rapid diffusion of electric vehicles. First, a partitioned-pricing system is proposed to create an advantage for electric vehicles in terms of initial purchasing cost relative to traditional internal combustion vehicles. Second, focusing on reducing switching costs is important because electric vehicles have relatively low resale values due to the uncertainty of battery life. Third, a battery-leasing strategy is supposed to reduce the cost of switching from a traditional internal combustion vehicle to an electric vehicle. Conclusions - This paper can provide strategic guidance for decision makers in firms that have already entered the electric-vehicle leasing market by making a recommendation such as a service innovation strategy. The proposed strategy can be considered as an electric vehicle market in the future and can contribute to the wider diffusion of electric vehicles.

발전소용 4.16 kV급 차단기에서 감전사고 사례 분석 (Analysis of Electric Shock Accident on 4.16 kV Class Circuit breaker for Power Plant)

  • 박남규;송재용;김진표;고재모
    • 한국안전학회지
    • /
    • 제29권4호
    • /
    • pp.54-60
    • /
    • 2014
  • This paper describes electric shock accidents on a 4.16 kV class circuit breaker for power plant. Electric shock accidents mostly involve damage of human life, in comparison with electrical fire, rate of human death tend to be higher in electric shock accidents. Specially, in a high voltage facilities rate of human death comprised about 43.7% by electric shock accidents. If electric shock accidents happen in a 4.16 kV class circuit breaker for power plant, then the power plant discontinue power production. Electric shock accidents in a power plant have a great ripple effect such as an electric power shortage. In this paper, we analyzed electric shock accidents on a 4.16 kV class circuit breaker for power plant. From the analysis results, we confirmed a cause of electric shock accidents on a 4.16 kV class circuit breaker, it happened by defect of interlock equipment or occurrence of breakdown between first feeder contactor and shielding plate. In order to reduce electric shock accidents on a 4.16 kV class circuit breaker, the power plant should consider improvement of interlock equipment and insulation of feeder contactor in circuit breaker.