• Title/Summary/Keyword: 자기유도등

Search Result 1,050, Processing Time 0.027 seconds

Battery Charging System using Magnetic Induction (자기유도를 이용한 배터리 충전 시스템)

  • Lim, Ji-Hun;Han, Ki-Dong;Park, Dong-Kook
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.17 no.10
    • /
    • pp.2239-2244
    • /
    • 2013
  • Industrial machines have constraints on movement due to its wire for power supply. Recently, the research on wireless power supply for industrial machine which is required to move freely is receiving a lot of attention. In this paper, we suggest a magnetic induction system which can charge a equipment's battery with wireless at a close range. The system was designed to operate at 13.56 MHz and a distance of 20~30 mm between the transmitting and the receiving power module. From experiment, it was found that it takes about 135 minutes for charging the battery with about 15 V using the proposed system.

Determination of the Magnetic Moment of ${\alpha}-Fe_{2}O_{3}$ of the Parasitic Ferromagnetism by the Proton Relaxation in Water (물의 양성자완화에 의한 기생 강자성 ${\alpha}-Fe_{2}O_{3}$의 자기능률 결정)

  • Yong-Jin Kim;Jung-Gi Kim
    • Journal of the Korean Magnetics Society
    • /
    • v.4 no.3
    • /
    • pp.282-284
    • /
    • 1994
  • A theoretical expression for determining the effective magnetic moment of hematite(${\alpha}-Fe_{2}O_{3}$) particle of the parasitic ferromagnetism by the proton relaxation in water is derived. In deriving the expression it is found that the mathematical procedures are exactly the same as those applied for aqueous solutions containing free paramagnetic ions, except that the distance between the proton spin of water molecule and the corresponding electronic spin of the particle must be considered to be a radius vector rather than a relative distance. And it is also found that the average effective magnetic moment of the particle calculated by the expression is in good agreement with the experimental value determined by Hirai.

  • PDF

Detection of a Magnetic Dipole by Means of Magnetic Gradient Tensor (자력 변화율 텐서를 이용한 자기 쌍극자 위치 결정)

  • Rim, Hyoung-Rea
    • Journal of the Korean earth science society
    • /
    • v.32 no.6
    • /
    • pp.595-601
    • /
    • 2011
  • In this paper, I propose the algorithm that the location of a magnetic dipole can be detected from the magnetic gradient tensor. I induce the location vector of a vertically magnetizated dipole from the magnetic gradient tensor. Deficit of magnetic moment of magnetic dipole makes the induced location information incomplete. However, if the observation of magnetic gradient tensor would be collected on more points, the algorithm is able to catch the location of the magnetic dipole by clustering the solution of the proposed algorithm. For example, I show that the synthetic case of borehole observation of magnetic gradient tensor can find the source location successively by picking common solution area.

Construction of Large 3-axis Square Helmholtz Coil system for the Power Frequendy Magnetic Field Immunity Test (전원주파수 교류자기장 내성평가용 대형 3-축 사각 헬름홀쯔 코일 시스템 제작)

  • 유권상;김창석;정낙삼
    • Journal of the Korean Magnetics Society
    • /
    • v.5 no.5
    • /
    • pp.905-909
    • /
    • 1995
  • We constructed the large 3-axis square Helmholtz coil system for the power frequency magnetic field immunity test. We measured the coil factors and magnetic field homogeneities of the fabricated 3-axis square Helmholtz coil. The experimental results for the field homogeneities are in agreement with the theoretical data. From these results, we determined the effective areas for the immunity test. We also confirmed that the low current using the multi-turns coil can be applicable to the immunity test for the high field in short duration.

  • PDF

Noise Removal in Magnetic Resonance Images based on Non-Local Means and Guided Image Filtering (비 지역적 평균과 유도 영상 필터링에 기반한 자기 공명 영상의 잡음 제거)

  • Mahmood, Muhammad Tariq;Choi, Young Kyu
    • KIISE Transactions on Computing Practices
    • /
    • v.20 no.11
    • /
    • pp.573-578
    • /
    • 2014
  • In this letter, we propose a noise reduction method for use in magnetic resonance images that is based on non-local mean and guided image filters. Our method consists of two phases. In the first phase, the guidance image is obtained from a noisy image by using an adaptive non-local mean filter. The spread of the kernel is adaptively by controlled by implementing the concept of edgeness. In the second phase, the noisy images and the guidance images are provided to the guided image filter as input in order to produce a noise-free image. The improved performance of the proposed method is investigated by conducting experiments on standard datasets that contain magnetic resonance images. The results show that the proposed scheme is superior over the existing approaches.

COG (Chip On Glass) Bonding Technology for Flat Panel Display Using Induction Heating Body in AC Magnetic Field (교류자기장에 의한 유도가열체를 이용한 평판 디스플레이용 COG (Chip On Glass) 접속기술)

  • Lee Yoon-Hee;Lee Kwang-Yong;Oh Tae-Sung
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.12 no.4 s.37
    • /
    • pp.315-321
    • /
    • 2005
  • Chip-on-glass technology to attach IC chip directly on the glass substrate of flat panel display was studied by using induction heating body in AC magnetic field. With applying magnetic field of 230 Oe at 14 kHz, the temperature of an induction heating body made with Cu electrodeposited film of 5 mm${\times}$5 mm size and $600{\mu}m$ thickness reached to $250^{\circ}C$ within 60 seconds. However, the temperature of the glass substrate was maintained below $100^{\circ}C$ at a distance larger than 2 mm from the Cu induction heating body. COG bonding was successfully accomplished with reflow of Sn-3.5Ag solder bumps by applying magnetic field of 230 Oe at 14 kHz for 120 seconds to a Cu induction heating body of 5mm${\times}$5mm size and $600{\mu}m$ thickness.

  • PDF