• 제목/요약/키워드: electromagnetic fields

검색결과 634건 처리시간 0.023초

지하철과 국철에서의 전계 및 자계 (Electromagnetic fields in subways and national railway)

  • 유창용;남기창;김덕원
    • 대한의용생체공학회:학술대회논문집
    • /
    • 대한의용생체공학회 1997년도 춘계학술대회
    • /
    • pp.299-302
    • /
    • 1997
  • Recently, many people are interested in the electromagnetic fields(EMF), so we measured the strength of electromagnetic fields in the carriages of national railways and subways. We also measured on the platforms of national railways and subways. The strength of EMFs on the platforms of national railways was stronger than that of subway's platforms. EMF measured on the platform during railway carriage's arriving and leaving was stronger than that without carriages. The strength of the magnetic fields in the carriages of national railways was measured stronger than that of subway's carriage while national railway is run by AC while subway is run by DC. Also The strength of the subway line 8 were measured stronger two to three times than others.

  • PDF

Reduction Characteristics of Electromagnetic Penetration through Narrow Slots in Conducting Screen by Loading Parallel Wire Arrays

  • Kim Ki-Chai;Lim Sung-Min
    • Journal of electromagnetic engineering and science
    • /
    • 제6권2호
    • /
    • pp.123-129
    • /
    • 2006
  • This paper presents a method of reducing penetration of penetrated electromagnetic fields through a narrow slot with parallel wire arrays in a planar conducting screen of infinite extent. An integral equation for the aperture electric field on the narrow slot is derived and solved by applying Galerkin's method of moments. When a plane wave is excited to the narrow slot, the aperture electric field is easily controlled by the parallel wire arrays connected on the slot and therefore the magnitude of the penetrated electric field is effectively reduced by loading the parallel wire arrays. The numerical results show that the magnitude of the penetrated electromagnetic field can be effectively reduced by installing the parallel wire arrays on the slot. The results of the calculated penetration electric fields are in good agreement with that of the measured results.

저항시트 장하에 의한 슬릿 침투 전자파의 저감 특성 (REDUCTION CHARACTERISTICS Of ELECTROMAGNETIC PENETRATION THROUGH MARROW SLOTS BY RESISTIVE SHEETS LOADING)

  • 박은정;주창현;김기채
    • 한국전자파학회:학술대회논문집
    • /
    • 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
    • /
    • pp.433-436
    • /
    • 2005
  • This paper presents the reduction methods of penetrated electromagnetic fields through a narrow slot aperture in a planar conducting screen of infinite extent. When a plane wave is excited to the narrow slot, the aperture electric field is controlled by the resistive sheets loaded on the slot. The magnitude of penetrated electromagnetic fields through a narrow slot is controlled by electric field distributions on the slot aperture. The results show that the magnitude of the penetrated electromagnetic field can be effectively reduced by the resistive sheets on the slot aperture.

  • PDF

PCB의 EM해석을 위한 FMM (FMM for the electromagnetic analysis of PCB)

  • 오세준;오재현;안창회
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2008년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.111-112
    • /
    • 2008
  • Induced electromagnetic fields of printed circuit board are computed using method of moment. In this calculation PEC and dielectric boards are considered when exposed to the external fields. The volume and surface integral equations are presented for the electromagnetic wave scattering from plate structures composed of dielectric and conducting objects. To reduce the computing time a fast multipole technique is applied.

  • PDF

직선으로 가설되어 있는 3상 전력선에 3성 분기선로가 있는 경우의 전자파 전자계 (Electromagnetic fields under 3-phase power lines with branch lines)

  • 김부규;노일수;강대하
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
    • /
    • pp.685-687
    • /
    • 2005
  • In this study, near the 3-phase power lines with branch lines were formulated. In rectangular coordinates, dependence of branch angle $\alpha$ on electromagnetic field components $B_x,\;B_y,\;B_z$$E_x,\;E_y,\;E_z$ was analyzed. The resultant electromagnetic fields B and E were discussed.

  • PDF

한국형 고속열차 내부 전자계 측정과 평가 (Electromagnetic Fields Measurement and Evaluation for Korean High Speed Train Prototype)

  • 이태형;장동욱;박춘수;목진용;서승일
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2004년도 추계학술대회 논문집
    • /
    • pp.1444-1448
    • /
    • 2004
  • The railway electromagnetic environment is much more severe than that found in commercial and domestic environments. However, in many instances the railway runs very close to such environments. Tn this paper we measure the strength of electromagnetic fields for Korean High Speed Train Prototype and compare that with the past result and evaluate the result according to domestic and international guideline.

  • PDF

유전체 내의 두개의 빈 원기둥에 의해 산란된 전자파의 감쇄패턴 (attenuation pattern of the electromagnetic fields scattered by two empty circular cylinders in a dielectric medium)

  • 이택경;김세윤;라정웅
    • 전자공학회논문지A
    • /
    • 제33A권4호
    • /
    • pp.92-97
    • /
    • 1996
  • The attenuation pattern of the E-polarized electromagnetic fields scattered by two empty circular cylinders in a dielectric medium is analyzed to calculate the effects of the inhomogenuity in hte background medium. Inthe amplitude pattern of the electromagnetic field scattered by one cylinder, double dips occur at the locations corresponding to its top and bottom boundaries. The distorton of the original double dip pattern is calculated when other air cavity approaches or its size increases.

  • PDF

방사 전자파에 의한 미소 간극 방전원의 방전 전류파형 추정 (Estimation of Discharge Current Waveshapes in Short Gap Discharge by Radiated Electromagnetic Fields)

  • 김기채;이광식;이동인
    • 한국전자파학회논문지
    • /
    • 제11권2호
    • /
    • pp.259-267
    • /
    • 2000
  • 본 논문에서는 미소 간극에서 방전이 일어날 때 발생하는 방사 전자파를 측정하여 이로부터 방전전류의 파형 을 추정하는 방법에 관하여 검토하고 있다. 시간영역 전자계 측정용 안테나를 사용하여 적절한 위치에서 관측한 측정 전계 또는 측정 자계로부터 방전전류를 추정하는 1 안테나 법(단일 전자계 법)과 2 안테나 법(복수 전자계 법)을 제시하고, 측정된 전계를 이용하여 1 안테나 법 및 2 안테나 법에 의한 방전전류의 파형을 추정(복원)하 고 였다. 추정된 방전 전류파형은 Wilson & Ma의 방전 전류 측정 결과와도 비교하여 본 논문에서 제시한 2가지 추정볍 이론의 타당성을 확인하고 있다.

  • PDF

운동중인 플라즈마 층으로 덮인 평면 도체성의 개구면에 의한 복사전자계 해석 (Analysis of Electromagnetic Fields Radiated from an Aperture on Conducting Plane Covered with a Moving Plasma Layer)

  • 김남태;이상설
    • 전자공학회논문지A
    • /
    • 제28A권9호
    • /
    • pp.715-720
    • /
    • 1991
  • The electromagnetic fields radiated from an aperture on a conducting plance covered with a moving uniaxial plasma layer are analyzed. From wave equations in moving plasma and free space region, their solutions are obtained and radiation fields are determined by applying proper boundary conditions in each region. For a particular case of isotropic plasma layer, our results correspond to well-known results.

  • PDF

극 저주파 및 휴대전화 전자파 환경 변수를 고려한 새포막 활동 전위 모형 (A Computational Model for a Neuronal Membrane Considering the Extremely Low Frequency and Mobile Phone Frequency Electromagnetic Field Effect)

  • 서영준;이은주;안재목;이용업;황태금;이재선;서정선
    • 대한의용생체공학회:의공학회지
    • /
    • 제24권4호
    • /
    • pp.347-354
    • /
    • 2003
  • 본 논문에서는 극 저주파와 휴대전화 전자파 (외부전자파) 환경의 영향이 고려된 세포막 활동 전위의 모의실험 모형을 제안하였다. Hodgkin과 Huxley 모형을 기초로 한 이 모형은 주사 전류 (injection current)에 전자파 효과를 적용하였으며 전자파의 주파수 영역에 대한 수치적 모의실험을 통하여 Strength-Duration 곡선을 얻는데 사용되었다 모의실험에서 사용된 수치해석 방법은 Runge-Kutta Fehlberg 방법이다. 모의실험에 고려된 주파수 영역은 1 Hz에서 100 Hz 사이와 이동통신에서 사용되는 900 티Hz의 주파수였다. 모의실험을 통하여 얻은 Strength-Duration 곡선은 Hodgkin과 Huxley가 제안한 방정식과 잘 일치함을 보여주었다.