• Title/Summary/Keyword: external magnetic field

검색결과 448건 처리시간 0.035초

다수의 접합경계를 갖는 $Nb_3$Sn 케이블 접합부의 직류 저항 특성 (DC Performance of $Nb_3$Sn Cable Joints with multi-interfaces)

  • 이호진;김기백;연제욱;홍계원;김기만
    • 한국전기전자재료학회논문지
    • /
    • 제13권2호
    • /
    • pp.170-176
    • /
    • 2000
  • The joints with multi-interfaces was expected to have low DC resistance compared with those with single interface. The small size joint specimens joined with Nb3Sn sub-cables were fabricated to investi-gate the DC performance in the range of 0 to 600A transport current without external magnetic field. The joints with multi-interfaces have a few n-Ohm resistance, which is much lower than that of single lap joint. Because the interfaces between sub-cables of multi-interfaced joint are more complicated than those of single-interfaced joint, the soldering condition between sub-cables is very effective on the joint DC resistance.

  • PDF

GIS 스페이서의 에폭시 주입구 장착형 UHF PD 센서의 성능 비교 (A comparison of the characteristics of External type UHF partial discharge sensor for metal covered barriers in GIS)

  • 황철민;김영노;이영상;곽주식;박기준
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
    • /
    • pp.2265-2267
    • /
    • 2005
  • We present detailed studies of externally applicable UHF PD sensors for a metal covered epoxy barrier with a small opening of epoxy injection-hole. The sensors were attached at the surface of injection hole of a metal covered epoxy barrier. 3-Dimensional electro magnetic simulations were performed to analyze electric-field distribution of the GIS and epoxy barrier with injection hole. Sensor structures were designed and analyzed using the 3-D EM simulator then fabricated for experimental verification. Sensor performance was measured in terms of spectral response and detected peak power. Real scale GIS and epoxy barriers were used to test and measure various aspect of performance of the sensors.

  • PDF

고안전 차량의 통합섀시 제어를 위한 지능형 현가시스템 변위 센서 개발 (Development of a intelligent suspension displacement sensor for unified chassis control of advanced safety vehicle)

  • 윤득선;이창석;백승환;강태호;부광석
    • 센서학회지
    • /
    • 제18권5호
    • /
    • pp.393-401
    • /
    • 2009
  • This paper describes development of a new displacement sensor for intelligent suspension system in which the damping force has been controlled by MR fluid. Most of the current vehicle height sensors have been installed at external place of the damper and connected to that by mechanical linkages so far. The developed sensor has a new mechanism which detects movement of the sensor rod same as connecting rod in the suspension damper by using a GMR Sensor and converts it to the relative displacement from an initial position.

불균일 전류분포가 Bi-2223/Ag 초전도선재의 통전손실에 미치는 영향 (Influence of non-uniform current distribution on transport ac loss in Bi-2223/Ag tapes)

  • 최세용;나완수;주진호;김정호;류경우;손명환;권영길
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
    • /
    • pp.1240-1242
    • /
    • 2005
  • In this study, we estimate the transport current loss of Bi-2223/Ag tapes with non-uniform current distribution. The conductor was consisted of three Bi-2223/Ag tapes and the each tapes were attached in parallel. The loss of conductor was investigated both numerical and experimental methods. The numerical code to predict ac loss was developed, and finite element method was introduced. It contained intrinsic properties of superconducting tape, which was obtained from nonlinear current voltage relation with external magnetic field and its orientation. Two results were compared and discussed. They showed good agreements with each other.

  • PDF

3D Plasma simulation을 이용한 Cylindrical Rotating Magnetron Sputtering Cathode 개발

  • 천용환;오지영
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
    • /
    • pp.179.1-179.1
    • /
    • 2013
  • Cylindrical Rotating Magnetron Sputtering Cathode (이하 Rotary Cathode)는 기존에 사용 되던 rectangular type 보다 Target 사용 효율이 높다는 큰 이점을 가지고 있다. 높은 Target 사용 효율은 비용 절감 효과와 직접적으로 관련 된다. 이번 연구는 3D Plasma simulation(PIC-MCC)을 통한 Target 사용 효율 80% 이상의 Rotary Cathode 개발을 목적으로 한다. Plasma simulation에 External Magnetic fields를 접목하여 Electron의 이동 궤적을 제어하였고, 생성된 Ion (Ar+)의 밀도 및 속도로 Plasma의 안정성과 Erosion 계산 구간을 선정 하였다. Target Erosion Profile은 Sputtering yield Data와 Target에 충돌한 Ion 정보를 사용하여 산출 하였으며, Sputtered Particles의 Deposition Profile은 계산된 Target Erosion Profile과 The cosine law of emission을 이용하여 계산 하였다. 실험 조건은 Plasma simulation의 초기조건 바탕으로 하여 2G size의 ITO Target을 대상으로 실험 하였다. 비 Erosion 영역 최소화하기 위해 Magnet Length를 변경하여 제작 적용 하였다. Simulation 계산 시간의 제약으로 인하여 simulation에서 생성된 최대 이온 밀도는 일반적으로 알려진 값 보다 적게 계산 되었지만, Simulation으로 예측한 Erosion Profile 및 Deposition Profile은 실험 값과 유사한 형태를 나타났으며, 실험 결과는 Target 사용 효율 80%이상의 결과를 보였다.

  • PDF

기계적으로 분할된 YBCO 선재의 교류손실 감소에 대한 연구 (A study on the reduction of ac loss of YBCO coated conductor by a mechanical striation method)

  • 유용수;홍계원;이희균
    • 한국초전도ㆍ저온공학회논문지
    • /
    • 제11권1호
    • /
    • pp.9-15
    • /
    • 2009
  • High temperature superconductor (HTS) coated conductors has high hysteretic magnetization loss which is an obstacle for the AC applications of coated conductors. We propose a method to reduce the magnetization loss of the coated conductor. It is the mechanical striation method by load variety using office knife. The magnetization loss measured in the mechanical striated YBCO coated conductor without copper layer was compared with the loss generated by perpendicularly exposed external magnetic filed. The reduction in magnetization loss due to the mechanical striation is clearly shown at higher field and was dependent on the striation number. The mechanical striation method was proven to have additional advantages of a low cost and high fabrication process.

한방부인과질환에 사용되는 치료방법에 대한 조사연구 (A Survey on the Treatments used in Oriental Obsterics & Gynecology)

  • 이인선;배경미
    • 대한한방부인과학회지
    • /
    • 제22권1호
    • /
    • pp.203-230
    • /
    • 2009
  • Purpose: In order to know therapies used in the field of Obsterics & Gynecology of Oriental medicine. Methods: This survey investigated papers about clinical study, literature investigation for therapeutic methods and treatment reports published from 1999. 2${\sim}$2008. 11. Results: In the clinical studies, acupuncture is more frequently used than herbal medicine. But in the treatment reports, herbal medicine is most frequently used except some cases. Besides acupuncture and moxibustion was used frequently. In the treatment reports various acupuncture methods were used except vaginal bleeding or abdominal pain cases. Whole body acupuncture was used mainly. Pharmacopuncture, Sa-am Acupuncture, auricular acupuncture was also used frequently. And Dong's acupuncture, Hwa acupuncture was used sometimes. Moxibustion was tend to be used for dysfunctional uterine bleeding, menopausal disorder, urinary incontinence, vaginal bleeding or abdominal pain during pregnancy period, hyperemesis, recurrent miscarriage, postpartum disease, lochiorrhea. Also other treatment methods was used such as external therapy, aromatherapy, herbal retention enema, fumigation, electric lipolysis acupuncture, Chuna manual medicine, obesity management, acupuncture at uterus cervix, magnetic innervation therapy, exercise, cupping and physical therapy. Conclusion: These results suggests that acupuncture, moxibustion and herbal medicine are most frequent therapy in the field of Obsterics & Gynecology of Oriental medicine. And other therapy are used such as external therapy, aromatherapy, herbal retention enema, fumigation and so on.

캡슐 내시경의 외부 수신기용 UWB 안테나 설계 (Design of UWB Antenna for the External Receiver of Capsule Endoscopy)

  • 김홍석;오민석;천창율
    • 한국전자파학회논문지
    • /
    • 제16권8호
    • /
    • pp.790-796
    • /
    • 2005
  • 본 논문에서는 캡슐 내시경의 무선통신이 이루어지기 위한 환경 연구와 더불어 그에 적합한 수신 안테나를 설계하였다. 제안된 안테나는 인체와 같은 multi-loss layer환경에서 전파 손실을 최소화 하고 magnetic field를 이용하기 위해 루프 안테나로 설계했다. 주파수 대역은 인체 내 전파 손실을 고려하여 $400\~500$ MHz이고 FCC 규정에 따라 인체 각각의 조직에 대한 유전율과 도전율을 추출했다. 이를 하나의 등가 모델로 설정하고 그에 따른 유전율과 도전율을 계산해서 인체를 대신할 수 있는 수용액을 제조하였다. 전파 손실이 심한 인체 내에서 캡슐이 이동함에 따라 수신 레벨이 급격히 감소하기 때문에 배열 안테나가 요구된다. 1 mW의 신호를 송신하는 송신 안테나 위치에 상관없이 배열 안테나의 신호 레벨은 평균 -60 dBm 정도로 충분한 신호 검출이 가능한 것을 확인했다.

주파수 영역법을 이용한 페라이트 물질이 포함된 스트립 선로 특성 해석 (Analysis of Characteristics for Strip Line with a Ferrite Material using Spectral-Domain Method)

  • 박진수;양승인
    • 한국전자파학회논문지
    • /
    • 제10권4호
    • /
    • pp.498-505
    • /
    • 1999
  • 비가역적인 특성을 갖는 페라이트 소자는 다양한 마이크로파 소자로서 사용되어져 왔다. 본 논문에서는 지 금까지 발표된 적이 없는 구조(페라이트 물질이 포함된 다증 구조인 스트립 선로)의 특성을 주파수 영역법을 이용하여 해석하였다 이 때 외부 de 자계를 접지 도체에 수직되게 가하였다고 가정하였으며, 각 파라메타와 주파수에 따른 전파상수뜰 계산하였다. 또한 기저함수(basis function)의 개수의 증가에 따른 수렴과 해석한 계산 결과의 타당성도 확인하였다 계산 결과. YIG의 두께가 증가할수록 차단되는 영역이 넓어지고, 차단되는 영역 이후의 주파수에서는 전 파상수가 작아짐을 알 수 있었다 그리고 인가되는 dc 자계 $\mu_0H_0$가 커짐에 따라 차단되는 영역의 주파수가 커짐을 알 수 있었다. 또한 스트립 선로의 시융레이션 결과가 마이크로스트립 선로의 경우보다 차단되는 영 역이 더 넓고, 전파상수기 큼을 알 수 있었다.

  • PDF

차세대 고온초전도 선재를 이용한 영구전류시스템의 히터트리거 특성 해석 (A Characteristic Analysis of Heater Triggered Persistent Current System with 2G High Tc Superconducting Tape)

  • 박동근;강형구;양성은;안민철;윤용수;윤경용;이상진;고태국
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
    • /
    • pp.1228-1230
    • /
    • 2005
  • This paper deals with design of heater trigger switching in a persistent current system(PCS) by finite element method(FEM) analysis of YBCO coated conductor(CC) tape. Most promising superconducting wire is YBCO coated conductor tape in these days for its high n value and critical current independency from external magnetic field. It is expected to be used many superconducting application such as fault current limiter and cable etc. The superconducting magnet which is operated in persistent current mode in SMES, NMR, MRI and MAGLEV has many advantages such as a high uniformity of a magnetic field and reducing a thermal loss. A PCS system consists of magnet power supply (MPS) which energized current to a magnet, heater, a coated conductor tape for switching, and superconducting magnet. In this paper, the characteristic of thermal quench of the YBCO CC tape and BSCCO tape by heater trigger analyzed by FEM. And optimal length of heater is calculated by temperature and time analysis. This heater trigger analysis is expected to be a basic concept of PCS application design.

  • PDF