• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.38.1-38.1
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• 2010

We present the results of the survey for submillimeter galaxies in the MS0451 (04h 54m 10.8s, -03d 00m 57.0s) at z = 0.55 and PKS1138-262 (11h 40m 48.25s, -26d 29m 10.1s) at z = 2.16 with the 1.1mm bolometer array AzTEC at the James Clerk Maxwell Telescope. The samples were centered on a prominent large-scale structure overdensity. Submillimeter galaxies seem to be starburst galaxies at high redshift ($z\;\geq\;1$) with high starformation rates ($\sim1000M\odot\;yr^{-1}$) or active galactic nuclei (AGN). We have obtained AzTEC images using the AzTEC data reduction pipeline with the IDL language. Through a bayes' theorem, we determined the extragalaxy catalogue, containing the false-detection rate, completeness, flux deboosting correction, and the source positional uncertainty in this region. We compared the catalogue with HST, DSS, 2MASS observations.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.596-598
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• 2001

This paper presents an analysis of the characteristics in switched reluctance motor (SRM). 2D finite element method (FEM) considering the iron saturation and the actual switching circuit of the SRM drive is applied for the dynamic analysis. The influence of the rotor shape on the radial force and torque ripple is investigated and the optimal shape of rotor pole is proposed to enhance the torque. The radial force characteristics acting on the surface of teeth is investigated by using the Maxwell's magnetic stress tensor method.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.29-34
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• 2008

A modeling technique for the 2-way coupling of heat transfer and conduction currents has been performed to inspire a combined analytical simulation. The 3-D finite element method is used to solve steady conduction currents and heat generation in an aluminum film deposited on a silicon substrate. The model investigates the temperature in the device after the current is applied. The conservation equation of energy, the Maxwell equations for conduction currents, the unsteady state heat transfer equation and the Fourier's law for heat transfer are implemented as a bidirectionally coupled problem. It is found that the strongly coupled temperature and time dependent heat equations give a reasonable results and an explicit solving technique.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.907-908
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• 2006

The energy storage systems are being widely researched for the electric power. The operations running in a vacuum chamber mainly consists of a composite flywheel rotor, superconductor bearings, a motor/generator and its controller. Among composed the apparatus, the floating magnet bearing consists of the ring-type permanent magnets with epoxy resin impregnation for reinforcement and surface protection. In order to storage as much energy as possible, the flywheel is supposed to be rotated with very high speed. The magnetic field is analyzed by using the Maxwell 2D/3D for the simulations.

• Proceedings of the KIPE Conference
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• 2012.07a
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• pp.83-84
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• 2012

본 연구는 3상 농형 유도전동기 보다 많은 특성을 가지는 다상 교류전동기의 구동 시스템 연구를 위하여 개발된 5상 3.0Kw 내부장착 영구자석 릴럭턴스 동기전동기(PMA-RSM)의 설계 및 제작에 대한 내용이다. 전동기 설계에는 Maxwell 2D/3D와 Simplorer의 EM Package 및 전동기 해석 프로그램을 활용하였다. 설계된 5상 PMA-RSM의 고정자와 회전자 구조의 특성과 제작된 전동기의 형태를 보여준다. 또한 고정자 권선방법으로 채택된 집중권에 대한 자계의 FEM 해석 결과와 기초적인 운전특성을 보여 준다.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.965-967
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• 1993

In this paper, Take two perment magnets and three iron bars and wind copper wire around one or the bars. This paper demonstrate that the method or calculation yields the right results with MAXWELL-2D program package for computing magnetic field, also indicate the value to which the current in the coil has to be limited to prevent saturation of the iron or the cores. The Finally procedures for design of LDM are discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.11
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• pp.1575-1581
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• 2014

In this paper, eddy current loss, iron loss and heat transfer of PMSG with 2,000kW capacities were analyzed for wind turbine. The PMSG with 3 split magnet was analyzed using ansoft maxwell commercial program and, generator was tested by Back to Back converter with no load condition at laboratory. Rotor surface temperature was measured by Pt100 sensors for investigating heat transfer from rotor to atmosphere. The simulation results shows 27.4kW eddy current loss in no load condition and 50.2kW eddy current loss in rated load condition with 3 split magnet, and also shows 4.3kW iron loss in no load condition and 7.3kW iron loss rated load condition. The heat transfer coefficient of convection between rotor surface and atmosphere was investigated by $9.6W/m^2{\cdot}K$. Therefore the heat transfer from rotor to atmosphere was about 17kW(54%) and from rotor to air-gap was about 14.6kW(46%) in no load condition. It is identified that the cooling system for stator have to include the 46% of iron loss, and heat dissipation structure of rotor surface have to be suggested and designed for efficiency improvement of generator.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.331-332
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• 2008

최근 엘리노 현상과 기상이변(태풍 및 폭설)으로 갤로핑 및 전선도약(Sleet jump) 등에 따른 송전선로 상간단락 고장의 우려가 날로 증가하고 있다. 특히 345kV급 간선계통의 상간단락 고장은 순간전압 강화 등 전기품질 저하로 이어질 수 있다. 이에 본 논문에서는 345kV 2도체용 폴리머 상간스페이서를 개발하여 상간단락고장에 대한 근본적인 예방책을 제시하였다. 폴리머용 345kV 절연 설계, 고강도 FRP ROD 설계 및 턴버클을 이용한 미세조정 장치 적용, 코로나 방지를 위한 코로나 링 채용 등을 통하여 최적의 345kV 2도체용 상간스페이서를 고안하였다. 또한 상간스페이서 소재의 성능 평가 및 해석을 위하여 Maxwell 2D Field Simulator를 이용하여 모델링하였으며 갓 형상에 따른 전계분포 해석과 FRP와 고무 계면에서의 전계분포 해석도 수행하였다.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.2
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• pp.79-82
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• 2004

The RF inductive discharge or inductively coupled plasma (ICP) continues to attract growing attention as an effective plasma source in many industrial applications, the best known of which are plasma processing and lighting technicology. Although most practical ICP operate at 13.56 [MHz]and 2.65 [MHz], the trend to reduce the operating frequency is clearly recognizable from recent ICP developments. In an electrodeless fluorescent lamp, the use of a lower operating frequency simplifies and reduces cost of rf matching systems and rf generators and can eliminate capacitive coupling between the inductor coil and plasma, which could be a strong factor in wall erosion and plasma contamination. In this study, the configuration of ferrite and fixture which operates at the frequency of 2.65[MHz]was discussed as functions of the ferrite thickness and distance by using the electromagnetic simulation software (Maxwell 2D).

• New & Renewable Energy
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• v.16 no.2
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• pp.14-19
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• 2020

Recently, a project to build a carbon zero island with no carbon emissions has been carried out by replacing diesel generators with renewable energy sources in island areas where diesel generators supplied local loads as independent systems. To minimize damage to the lives of islanders, low noise wind generators should be installed by adjusting the rated speed. In islands with low loads, wind turbines that are more efficient than medium-sized wind turbines should be installed. In this study, the generator field analysis and characteristics were analyzed to develop 230 kW-class low wind medium-wind turbine technology. The electromagnetic field analysis program used Maxwell. As a result, the cogging torque was reduced, and the initial maneuver wind speed and loss value were lowered. Hence, the output amount was increased with high efficiency.