• 천문학논총
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• 제2권1호
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• pp.13-20
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• 1985

Magnetic reconnect ion is studied numerically by means of a two dimensional MHD code. The initial magnetic field configuration is the two-dimensional dipole field, and the simulation model involves magnetic reconnect ion driven by the magnetized plasma flow. Strong plasma jetting, plasmoid formation and its fast ejection are observed in the downstream region. The dependence of reconnection rate on the incoming energy flux is found to be very sensitive, while the magnitude of the resistivity does not influence much on the reconnection rate. The simulation results are discussed in the context of the geomagnetic substorm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.796-797
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• 2015

This paper deals with torque analysis of magnetic cycloid gear with radial magnetized permanent magnets based on analytical method. These analytical results are validated by comparing with the 2D finite element analysis (FEA).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2003년도 제24회 학술발표회 초록집
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• pp.214-214
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• 2003

• 천문학회지
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• 제37권4호
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• pp.233-235
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• 2004

High-velocity clouds are flows of neutral hydrogen, located at high galactic latitudes, with large velocities ($[VLSR]{\ge} 100 km/s$) that do not match a simple model of circular rotation for our Galaxy. Numerical simulations have been performed for the last 20 years to study the details of their evolution, and their possible interaction with the Galactic disk. Here we present a brief review of the models that have been already published, and describe newly performed three-dimensional magnetohydrodynamic simulations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.334-336
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• 1998

This paper deals with the problem of the magnetizing yoke fixture. The experimental test has been performed using the yoke fixture made of bakelite as well as ferromagnetic. The magnetizing current is the most essential criterial factor for delivering the impulse energy to the magnetized material, i.e ferrite core. The yoke of nonferromagnetic has shown its better performance in experimental results as well as in the finite element analysis.

• Journal of Magnetics
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• 제3권3호
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• pp.86-88
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• 1998

A portable RF HTS SQUID-based susceptometer was used for small size magnetized sample testing in weak DC (up to 200A/m) and AC (up to 4 A/m) magnetic fields. The system resolution for the magnetic moment is of the order of $1.6{\times}10^{-10} A.m^2$. The measured DC susceptibility of a tested sample agrees well with the value obtained by using a commercial liquid helium susceptometer.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.616-619
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• 2000

It is important to control the plasma characteristics for high quality plasma process. Recently, a novel method proposed by us, named as Enhanced-ICP, using periodic weak time-varying axial magnetic field added to a normal ICP source, has improved etch characteristics much. Variation of plasma characteristics according to the frequency of time-varying axial magnetic field have been measured and analyzed.

• 천문학회보
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• 제46권1호
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• pp.36.1-36.1
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• 2021

Galaxy clusters host Mpc-scale diffuse radio emission giving us evidence of large-scale magnetic fields in the Universe. It is relevant to understand magnetic field amplification processes occurring at the center and outskirts of galaxy clusters. Each of these processes are believed to give rise to observed radio haloes and radio relics, respectively. In this work, we focus on studying the continuum and polarised emission in radio relics. We use threedimensional magnetohydrodynamical simulations of merger shock waves propagating through a magnetized, turbulent intracluster medium. Our model includes the diffusive shock acceleration (DSA) of cosmic ray electrons, their spatial advection and energy losses at run-time. We discuss the relation between the mock observation features and the underlying morphology of the magnetic field.

• 천문학회보
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• 제46권2호
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• pp.47.2-47.2
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• 2021

The present study is focused on origins of the flow and magnetic structure involved in the formation and eruption of a solar prominence. To clarify them, we performed an MHD simulation based on the 3-dimensional emerging flux tube (3DEFT) model, in which self-consistent evolution of a flow and magnetic field passing freely through the solar surface was obtained by seamlessly connecting subsurface dynamics with surface dynamics. By analyzing Lagrangian displacements of magnetized plasma elements, we demonstrate the flow structure which is naturally incorporated to the magnetic structure of the prominence formed via dynamic interaction between the flow and magnetic field.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 1999년도 추계학술발표회 초록집
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• pp.56-56
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• 1999

For advanced TFT-LCD manufacturing processes, dry etching of thin-film layers(a-Si, $SiN_x$, SID & gate electrodes, ITO etc.) is increasingly preferred instead of conventional wet etching processes. To dry etch Al gate electrode which is advantageous for reducing propagation delay time of scan signals, high etch rate, slope angle control, and etch uniformity are required. For the Al gate electrode, some metals such as Ti and Nd are added in Al to prevent hillocks during post-annealing processes in addition to gaining low-resistivity($<10u{\Omega}{\cdot}cm$), high performance to heat tolerance and corrosion tolerance of Al thin films. In the case of AI-Nd alloy films, however, low etch rate and poor selectivity over photoresist are remained as a problem. In this study, to enhance the etch rates together with etch uniformity of AI-Nd alloys, magnetized inductively coupled plasma(MICP) have been used instead of conventional ICP and the effects of various magnets and processes conditions have been studied. MICP was consisted of fourteen pairs of permanent magnets arranged along the inside of chamber wall and also a Helmholtz type axial electromagnets was located outside the chamber. Gas combinations of $Cl_2,{\;}BCl_3$, and HBr were used with pressures between 5mTorr and 30mTorr, rf-bias voltages from -50Vto -200V, and inductive powers from 400W to 800W. In the case of $Cl_2/BCl_3$ plasma chemistry, the etch rate of AI-Nd films and etch selectivity over photoresist increased with $BCl_3$ rich etch chemistries for both with and without the magnets. The highest etch rate of $1,000{\AA}/min$, however, could be obtained with the magnets(both the multi-dipole magnets and the electromagnets). Under an optimized electromagnetic strength, etch uniformity of less than 5% also could be obtained under the above conditions.