• Journal of Magnetics
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• 제9권4호
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• pp.97-100
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• 2004

In the present work exchange coupling between ultrathin Fe ($8{\AA}$) and Tb ($12{\AA}$) layers separated by Au spacer of varied thickness ($3-20{\AA}$) was studied. Anomalous Hall effect measurements showed weakly damped oscillating dependence of the Hall conductivity as a function of Au spacer thickness. Disagreement of the observed damping with the RKKY model of interlayer exchange coupling was explained by the influence of external magnetic field on the behaviour of exchange coupling oscillations. It was confirmed by Hall-like effect measurements at zero applied magnetic field and also illustrated by corresponding estimations.

• Journal of electromagnetic engineering and science
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• 제18권1호
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• pp.35-40
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• 2018

This study presents a vertical-type CMOS Hall device with improved sensitivity to detect a 3D magnetic field in various types of sensors or communication devices. To improve sensitivity, trenches are implanted next to the current input terminal, so that the Hall current becomes maximum. The effect of the dimension and location of trenches on sensitivity is simulated in the COMSOL simulator. A vertical-type Hall device with a width of $16{\mu}m$ and a height of $2{\mu}m$ is optimized for maximum sensitivity. The simulation result shows that it has a 23% better result than a conventional vertical-type CMOS Hall device without a trench.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2000년도 International Symposium on Magnetics The 2000 Fall Conference
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• pp.337-345
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• 2000

The spontaneous Hall effect in amorphous Tb-Fe and Sm-Fe thin films, which possess excellent magnetic softness, is investigated in this work to seek a possibility of practical applications of these thin films as sensors. The resistivity of Tb-Fe thin films ranges from 180 to 250 Ωcm as the Tb content varies from 35 to 46 at. %. Tb-Fe thin films show negative Hall resistivity ranging from - 7.3 to - 5.0 Ωcm in the same composition range, giving the normalized resistivity ratio in the range of -4.1 to -2.0 %. On the other hand, the resistivity of Sm-Fe thin films ranges from 150 to 166 Ωcm as the Sm content varies from 22 to 31 at. %. Sm-Fe thin films show positive Hall resistivity which varies from 7.1 to 2.8 Ωcm in the same composition range, giving the normalized resistivity ratio in the range of 4.8 to 1.7 %. These values are significantly high compared with the values of other R-T alloys, Tb-Co alloys for example, where the highest reported value is 2.5 %. Between the two different sets of samples, Tb-Fe thin films with perpendicular anisotropy are considered to be more suitable for practical applications, since saturation is reached at a los magnetic field, approximately 2 kOe in a Tb$\sub$35.1/ Fe$\sub$64.9/ thin film, for example.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.119-123
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• 2007

Ventilation performance in the storage hall of Janggyeongpan Jeon has maintained for more than 600 years. Janggyeongpan Jeon in Haein temple has window structure of bi-level ventilating opening which consists of upper and lower window. Also, different size and shape of windows are adopted for various locations of the hall. In the present study, to analyze effect of shape of windows on ventilation performance in the storage hall, various design alternatives were considered. Numerical analysis of ventilation in the storage hall was investigated under the same simulation condition except for the shape of windows. Through the comparison of numerical results for various window designs, it was evaluated that the current windows shape gives best ventilation performance.

• 전자공학회논문지A
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• 제32A권1호
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• pp.138-145
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• 1995

The offset voltage in silicon Hall plates is mainly caused by stress and strain in package, and by alignment in process. The offset voltage is appeared random for condition change with time in the factory, is non-linearly changed with temperature. In this paper proposed new method of design of Hall IC, and methematicaly proved relation layout of chip of 90$^{\circ}$-shift-current Hall plate pair is matched with "Differentail to single ended Conversion amplifier." In the experiment, the offset voltage is reduced about 1/100 time than the original offset voltage.

• 산업경영시스템학회지
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• 제27권4호
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• pp.90-93
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• 2004

This paper is case study for ISO 9001/2000 quality management system certification of social welfare. We constructed quality management system for efficient operation for service quality improvement of welfare hall which is society welfare facilities. This paper evaluated operation actual conditions of "G" welfare hall which introduce and operates quality management system according to index of evaluate for society welfare hall and present improvement plan about effect and problem.

• 대한기계학회논문집A
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• 제36권2호
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• pp.231-236
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• 2012

본 논문에서는 홀 효과(Hall effect) 기반 회전형 위치 센서의 출력 전압에 대한 선형성 및 민감도를 최적화하기 위해 DFSS(Design for Six Sigma) 방법을 적용하였다. 이를 위해 영구 자석의 치수 및 홀센서에 대한 상대 위치 등을 설계 인자로 하여 완전 요인 배치법을 사용하였다. 설계 인자의 수준별 센서 출력 전압값은 자속 밀도에 대한 Biot-Savart 해석해 및 홀 센서 고유의 자속 밀도-출력 전압에 대한 관계식을 이용하여 구하였다. 최적화된 설계 인자들을 반영하여 제작된 회전형 위치 센서의 개선된 출력 전압 측정 결과를 통해 제안된 방법은 간편하면서 실용적으로도 매우 유용한 방법임을 확인하였다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2007년도 한국우주과학회보 제16권2호
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• pp.139-143
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• 2007

전기 추진시스템은 저렴한 개발비와 높은 신뢰성을 제공하는 추진 장치로 많은 분야에서 응용 되어 왔다. 특히 최근에 발사된 SMART-1과 MUSES-C는 우리에게 시사하는 바가 크다. 각각 European Space Agency(ESA)와 Japan Aerospace Exploration Agency(JAXA)에서 개발한 행성 탐사선으로, SMART-1은 달 탐사를 목적으로 하고 MUSES-C는 소행성 Itokawa의 토양을 채취해오는 것을 목적으로 한다. 이 두 탐사선에는 각각 Hall effect thruster와 Micro wave ion engine이 탑재되었는데, 작고 저렴한 비용의 탐사선을 이용해서 충분히 행성 탐사가 가능하다는 좋은 선례를 남겼다. 현재 개발되고 있는 과학기술위성 3호(STSAT-3)에도 전기추진 장치가 탑재되는데, SMART-1에 탑재 되었던 것과 유사한 Hall effect thruster가 인공위성 연구센터와 KAIST 물리학과의 GDPL과 공동으로 개발되고 있다. 성능이 좋은 전기 추력 장치를 개발하기 위해 추력기 내부에서 발생하는 플라즈마의 물리적 특성을 파악하는 것은 매우 중요한 일이다. 이 논문에서는 이러한 플라즈마의 특성을 모사하는 방법으로 Particle In Cell 모사와 더불어 독립적인 개개 입자의 운동을 기술하는 입자모사(particle simulation)를 이용하는 방법을 제시 하고자 한다. 이러한 접근 방법은 실제 전기추력장치를 설계하고 실험하는 담당자에게 플라즈마 운동에 대한 명료한 지식을 제공해 줄 수 있을 것으로 생각된다.

• Coupled systems mechanics
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• 제10권2호
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• pp.103-121
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• 2021

The present research deals with the investigation of the effect of hall current in an orthotropic magneto-thermoelastic medium with two temperature in the context of multi-phase-lag heat transfer due to thermomechanical sources. The bounding surface is subjected to linearly distributed and concentrated loads(mechanical and thermal source).Laplace and Fourier transform techniques are used to solve the problem. The expressions for displacement components,stress components and conductive temperature are derived in transformed domain and furtherin physical domain with the help of numerical inversion techniques. The effect ofrotation and hall parameter hasshown with the help of graphs.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제20권3호
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• pp.203-224
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• 2016

The heat and mass transfer characteristics of the unsteady hydromagnetic natural convection flow with Hall current and Soret effect of an incompressible, viscous, electrically conducting, heat absorbing and optically thin radiating fluid flow past a suddenly started vertical infinite plate through fluid saturated porous medium in a rotating environment are taken into account in this paper. Derivations of exact analytical solutions are aimed under different physical properties. The velocity, concentration and temperature profiles, Sherwood number and Nusselt number are easily examined and discussed via the closed forms obtained. Soret effect and permeability parameter tends to accelerate primary and secondary fluid velocities whereas hall current, radiation and heat absorption have reverse effect on it. Radiation and heat absorption have tendency to enhance rate of heat transfer at the plate. The results obtained here may be further used to verify the validity of obtained numerical solutions for more complicated transient free convection fluid flow problems.