• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.12-12
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• 2010

The hall probe measurement system was used to measure the critical current distribution of superconducting coated conductor. The system consists of reel to reel moving apparatus, 7 array hall probe, a rotary encoder and permanent magnet. The magnetic field profile across the width of superconducting coated conductor using Bean's critical state model was calculated. The effect of various parameters of the formulas on the magnetic field distribution and the effect of shape and size of artificial defects, which were formed on the surface of SmBa2Cu3O7-d(SmBCO) coated conductor using laser marking system, on the hall probe magnetic field signal of the hall probe measurement system was investigated.

• Journal of Power System Engineering
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• v.11 no.2
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• pp.72-76
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• 2007

Since the magnetic bearing system has unstability inherently it is necessary to measure the displacement for stable operation. Normally the displacement measurement is implemented by using sensors. The sensor for the displacement measurement is selected by precision, installation space, effect of magnetic field and response speed. And the cost of displacement measurement sensor also is considered. At the cost the hall effect sensor has a large advantage comparing with the others. Therefore this study concern about the basis experimental test for the displacement measurement of the magnetic bearing system that uses the hall effect sensor coupled with a tiny permanent magnet. The experimental results confirm the validity and practicability for this displacement measurement sensor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.05a
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• pp.7-8
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• 2009

Non-contact critical current measurement apparatus was developed using hall probe which measures the magnetic field distribution across the width of superconducting tape. The hall probe consists of 7 independent hall sensors which lie in a line 600 ${\mu}m$. The difference between maximum and minimum magnetic field in the magnetic filed distribution is a main parameter to determine the critical current. As preliminary research, we calculated the magnetic field intensity at the middle sensor, which is a minimum magnetic field and generated by the circular shielding current modeled by Bean model. We confirmed that there are some parameters that affect on the minimum magnetic field; the distance between superconducting layer and hall sensor, the width of superconducting tape, and the critical current distribution across the width of superconducting tape. Among these parameters, the distance between superconducting layer and hall sensor highly influences on the minimum magnetic field.

• Journal of the Semiconductor & Display Technology
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• v.17 no.3
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• pp.17-20
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• 2018

IGZO thin films were prepared on n-type Si substrates to research the interface characteristics between IGZO and substrate. After the annealing processes, the depletion layer was formed at the interface to make a Schottky contact owing to the electron-hall fair recombination. The carrier density was decreased by the effect of depletion layer and the hall mobility decreased during the deposition processes. But the annealing effect of depletion layer increased the hall mobility because of the increment of potential barrier and the extension of depletion layer. It was confirmed that it is useful to observe the depletion effect and Schottky contact's properties by complementary using the Hall measurement and I-V measurement.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.866-874
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• 2008

Motor frequency can be measured by a hall sensor. Among the many hall sensors, a linear type hall sensor is good at high accuracy frequency measuring problem. However, in general, this linear type hall sensor has DC offset which can vary along sensor's operating voltage change. Therefore, In motor frequency measurement problem using the linear hall sensor, it needs an estimator that can estimate frequency and DC offset simultaneously. In this paper, we propose the least mean square estimator to estimate motor frequency. To verify its performance, we compare the LMS estimator with a commercial analog tachometer. Experimental results shows the proposed LMS estimator works well in varying frequency and stationary DC offset.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.21-24
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• 2000

lnSb temperature dependent hall effect of multilayerd structures were investigated. According to variation of magnetic field measured hall coefficient, Hall mobility, carrier density and hall voltage. For the measurement of electrical properties of hall device, evaperated InSb thin film fabricated with series and parallel multilayers. We found that the XRD analysis of InSb thin film showed good properties at 20$0^{\circ}C$, 60 minutes. Resistance of ohmic contact increased linearly due to increasing current. Some of device fabrication technique and analysis of Hall effect were discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.1
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• pp.70-75
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• 2010

The objective of this paper is to propose a new velocity measurement method for an electro-mechanical fin actuator. The model of the electro-mechanical fin actuator includes uncertainties such as unknown disturbances and parameter variations in flight condition. So, an electro-mechanical fin actuator system needs robust control algorithm which requires not only position information but also velocity information. Usually, analog tachometers have been used for velocity feedback in an electro-mechanical fin actuator. However, using these types of sensors have problems such as the cost, space, and malfunction. These problems lead to propose a new velocity measurement method using linear type Hall-effect sensor. In order to verify the proposed method, several experiments are performed using Model Following Sliding Mode Controller(MFSMC). It is shown that the MFSMC with a new velocity measurement method using linear type Hall-effect sensor can satisfy the requirements without using of velocity sensor.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.3114-3120
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• 2023

A high-accuracy magnetic field measurement device based on a cyclotron is being developed for accelerator mass spectrometry (AMS). In this study, a magnetic field measurement device consisting of a Hall probe sensor, piezo-motor, and step motor was developed to measure the magnetic field of the AMS cyclotron magnet. The Hall probe sensor was calibrated to achieve positional accuracy by using polar coordinates. The measurement results between the ratchet gear and piezo-motor, which are the instruments used for driving the measurement device, were analyzed. The measurement result of the device with a piezo-motor exhibits a difference of 5 Gauss (0.04%) as compared with the simulation result.

• Journal of architectural history
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• v.25 no.4
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• pp.65-73
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• 2016

This paper aimed to identify the units of measuring scale in Hwangnyongsa temple planning with the published excavation survey reports. Hwangyongsa temple site was planned under Silla Capital's urban planning in 6~7C, its full size was $800{\times}800$, and main temple was $400{\times}515$ of Goguryeo's system of measurement. Main hall was located in the center of Hwangnyongsa temple site, and its location could be seen that there was the arrangement of main temple divided into 3 : 2. Building plan measuring units proved to be 351~356mm and 294~ 296mm by analyzing measured data of remains. Lecture hall and Wooden pagoda were rebuilt by using the ancestors' units of measuring scale again and Bell hall was not planned by Tang's system of measurement in middle of 8C. In this respect, it would be important to have a deliberate attitude and lay down stereotypes on research of the units of measuring scale in ancient architecture.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.8 no.2
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• pp.54-62
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• 1983

The electric characteristics of semiconductor materials can be found by way of various methods, of which the measurement of the carrier mobility is thought to be of great importance. There exist some mobilty measurements, but the measurement based on Hall effect is the most widely uesd. In this paper is adopted the mobility measurement of semiconductor by the use of cylindrical eavity operated in the same shape as TE modes. It is hoped that the resultant values of measurement, the structure of measurement circut, cavity design and the raising of relevant problems may give much help to those who may interested in this field.