• Journal of Magnetics
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• v.9 no.4
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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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• v.18 no.1
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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.

• Proceedings of the Korean Magnestics Society Conference
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• 2000.09a
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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.

• Proceedings of the SAREK Conference
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• 2007.11a
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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.

• International journal of advanced smart convergence
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• v.13 no.3
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• pp.367-375
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• 2024

Draft curtains are an important tool to reduce the spread of fire smoke in buildings. This paper mainly studies the influence of draft curtains on smoke spread in a hospital outpatient building with a spacious hall. The outpatient building of a county hospital in China is taken as the research object, and a fire simulation model is established based on PyroSim software. Four scenarios are designed: no draft curtains in the hall, draft curtains with a length of 1.5m in the hall, draft curtains with a length of 2.0m in the hall, and draft curtains with a length of 2.5m in the hall. At the same time, considering the worst situation, only the main emergency exit is opened, while the remaining emergency exits and windows are all closed, and the fire-fighting facilities are not activated. The detection point is set at the open emergency exit, 1.8m above the ground. Through the simulation of four scenarios, the effect of draft curtains on smoke spread is discussed from four aspects: smoke layer height, temperature, visibility, and CO concentration. The results show that draft curtains have a significant impact on the spread of smoke in a hospital outpatient building with a spacious hall. The longer the draft curtains are, the better the smoke-blocking effect. It should be noted that in the actual design, the length of the draft curtains should be considered without affecting the evacuation of personnel.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.1
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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.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.4
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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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.2
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• pp.231-236
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• 2012

This work presents the application of the DFSS (Design for Six Sigma) methodology to optimizing both the linearity and the sensitivity of the output voltage of a Hall-effect rotary position sensor. To this end, the dimensions and relative positions of a permanent magnet with reference to a Hall sensor are selected as the design factors for a full factorial design. In order to evaluate the output voltage of the rotary position sensor at each run in the experimental design, analytical solutions to the magnetic flux density were obtained using the Biot-Savart law and the relations between the magnetic flux density and the output voltage intrinsic to a Hall sensor. Through measurements of the improved output voltage of the rotary position sensors manufactured using the optimized design factors, the proposed method is shown to be simple and practical.

• Bulletin of the Korean Space Science Society
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• 2007.10a
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• pp.139-143
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• 2007

Electric propulsion has become a cost effective and sound engineering solution for many space applications. The success of SMART-1 and MUSES-C developed by European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA) each proved that even small spacecraft could accomplish planetary mission with electric propulsion systems. A small electric propulsion system which is Hall effect thruster like SMART-1 is under development by SaTReC and GDPL (Glow Discharge Plasma Lab.) in KAIST for the next microsatellite, STSAT-3. To achieve optimized propulsion system, it is very necessary to understand plasma motions of Hall effect thruster. In this paper, we try to approach comprehensive plasma model with the particle simulation complementary to Particle In Cell (PIC) simulation. We think these two different approaches will help experimenters to optimize Hall effect thruster performances.

• Coupled systems mechanics
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• v.10 no.2
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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.