• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.367-371
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• 2004

The purpose of this research is furnishing of basic material for acoustic planning hereafter, after understanding the acoustic merits and demerits through measuring and analyzing on room acoustic of small performance hall. As the result of the measurement, those physical evaluation indexes such as SPL, RT, EDT, $D_{50}$, $C_{80}$, RASTI have being kept the satisfiable acoustic condition for the service of performance hall. Therefore, as small performance hall is regarded as equipped with sufficient volume of sound, reverberatory feeling and diffusive feeling, it judges as an excellent performance place, also it is considered that it could be utilized as a useful material when design so similar performance hall, hereafter.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1266-1272
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• 2003

This paper presents a new class of magnetic microsensors based on the Hall effect in AC microplasma. In the theoretical study, we develop a simple model of the plasma Hall sensor and express the plasma Hall voltage as a function of magnetic field, plasma discharge field, pressure, and electrode geometry. On this basis, we have designed and fabricated magnetic microsensors using AC neon plasma. In the experiment, we have measured the Hall voltage output of the plasma microsensors for varying five different conditions, including the frequency and the magnitude of magnetic field, the frequency and the magnitude of plasma discharge voltage, and the neon pressure. The fabricated magnetic microsensors show a magnetic field sensitivity of 8.87${\pm}$0.18㎷/G with 4.48% nonlinearity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.86-89
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• 1994

This paper describes the fabrication and basic characteristics of a Si Hall device fabricated on a SOI(Si-on-insulator) structure. In which SOI structure was formed by SOB(Si-wafer direct bonding) technology and the insulator of the SOI structure was used as the dielectrical isolation layer of a Hall device. The Hall voltage and sensitivity of the implemented SDB SOI Hall devices showed good linearity with respectivity to the applied magnetic flux density and supple iud current. The product sensitivity of the SDB SOI Hall device was average 670 V/A$.$T and its value has been increased up to 3 times compared to that of bulk Si with buried layer of 10$\mu\textrm{m}$. Moreover, this device can be used at high-temperature, high-radiation and in corrosive environments.

• Journal for History of Mathematics
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• v.27 no.3
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• pp.211-231
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• 2014

Although Monty Hall dilemma is used in many areas including philosophy, economics, and psychology, it is used in the current mathematics textbooks only as a material for reading or one of probability questions. The present study tries to explore students' understanding of Monty Hall dilemma through a class case. In this study, a group of high-school students participated in group activities, in which they read an argument about Monty Hall dilemma, and tried to resolve it through small-group and whole-class discussions, and then studied the conditional probability. The analysis supports the studies in psychology that intuitive understandings on probability do not change easily, and that counter-intuitivity in Monty Hall dilemma induces confusion and offers a basis for discussions among students. Similar results are anticipated when other dilemmas on probability are used.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.3
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• pp.72-78
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• 1992

The Silicon vertical Hall devices are fabricated using standard bipolar process and characterized in terms of the Hall voltage, sensitivities, and offset voltage. The Hall voltage and sensitivity of the devices showed good linearity with respect to the magnetic flux density and reverse supply voltage Vr. The sensitivity of device with P$^{+}$ isolation dam has been increased up to 1.2 times compared to that of device without the dam. With the condition of V$_{r}$=-5.0[V], B=0.4[T] and I$_{sup}$=1.0[mA], the Hall voltage and sensitivity of the device with P$^{+}$ isolation dam were about 29[mV] and 74[V/AT], respectively. These vertical Hall devices can be used as the adjustable magnetic fields sensor.

• Journal of Electrical Engineering and Technology
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• v.11 no.4
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• pp.889-897
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• 2016

This paper presents an improved approach for compensating rotor position signal displacement in brushless DC (BLDC) motors with misaligned hall-effect sensors. Typically, the hall-effect sensors in BLDC motors are located in each phase and positioned exactly 120 electrical degrees apart. However, limitations in mechanical tolerances make it difficult to place hall-effect sensors at the correct location. In this paper, a position error compensator to counteract the hall-effect sensor positioning error is proposed. The proposed position error compensator uses least squares error analysis to adjust the relative position error and back-EMF information to reduce the absolute offset error. The effectiveness of the proposed approach is verified through several experiments.

• Journal of the Korean Magnetics Society
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• v.5 no.6
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• pp.952-955
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• 1995

It is well kown that the side-jump effect, originated from the spin-orbit scatterring of the transport electrons at the site of spin-orbit scatterers, is the reason for the anomalus Hall resistivity which is proportional to the magnetization. Our recent magnetization study implied that abundant ferromagnetic Fe clusters made of for Fe ions dominate the temperature and field dependence of magnetization at high field and low temperature regime for a paramagnetic $Fe_{0.33}Zr_{0.67}$ alloy. We measured the Hall resistivity of this alloy and observed that the Hall resistivity followed the M-H cure at low temperature, and the Hall coefficients at moderate temperatures were proportional to the magnetic susceptibility. We explain the behavior of Hall resistivity with the change of field and temperature in terms of side-jump effect.

• Journal of architectural history
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• v.20 no.5
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• pp.95-109
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• 2011

The building for the Sutra appeared as the Sutra-belief became popular in the early years of the Koryo Dynasty. According to the written documents, there were two types of apparatus to keep sutras, one by fixing the cabinet to the wall and the other by rotating the cabinet at the center of the hall. There are no remains. Recently, at the excavation of the site of the Yeongguk Temple (寧國寺) in the Chungcheong Prevince (영동군), a building which was presumed as the Sutra Hall was recovered at the side of the Main Hall. At the center of the building, of 6meters width and 6meters depth, there was a large stone which had a round trace which was presumed to supporting the rotating sutra-case cabinet. By examining the concerned situations, this building was concluded as the Sutra Hall of the temple. The Yeongguk Temple had a close relationship with the royal household. Budddhist monk Gwangji, son of the 16th King Yejong was lived at the Temple. the tomb of King's advisory priest Wongak was also erected at the Temple. Two monks were well known as the defender of the Sutra. The Sutra Hall of the Yeongguk Temple regarded as a significant example which showed us how the archtectural aspect of the Sutra Hall was shaped in the Koryo Dynasty. It could be said that revealing the architectural aspect of the Stura Hall will help revealing the Buddhist architecture of the Koryo Dynsty which is veiled in many field.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.454-454
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• 2011

Graphene shows unusual electronic properties, such as carrier mobility as high as 10,000 $cm^2$/Vs at room temperature and quantum electronic transport, due to its electronic structure. Carrier mobility of graphene is ten times higher than that of Silicon device. On the one hand, quantum mechanical studies have continued on graphene. One of them is quantum Hall effect which is observed in graphene when high magnetic field is applied under low temperature. This is why two dimension electron gases can be formed on Graphene surface. Moreover, quantum Hall effect can be observed in room temperature under high magnetic field and shows fractional quantization values. Quantum Hall effect is important because quantized Hall resistances always have fundamental value of h/$e^2$ ~ 25,812 Ohm and it can confirm the quantum mechanical behaviors. The value of the quantized Hall resistance is extremely stable and reproducible. Therefore, it can be used for SI unit. We study to measure quantum Hall effect in CVD graphene. Graphene devices are made by using conventional E-beam lithography and RIE. We measure quantum Hall effect under high magnetic field at low temperature by using He4 gas closed loop cryostat.

• Journal of architectural history
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• v.25 no.6
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• pp.17-25
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• 2016

Simgok Seowon is the commemorative shrine and academy established for scholar Jo Gwangjo (pen name : Jeongam). The shrine (sangnyangsik) and the east and west dormitories (Dongjae and Seojae) were built in 1636. The lecture hall, Imsimnu Pavilion, Sananggak and Munhyanggak buildings were built successively. Simgok Seowon is the only one that survived through the abolishment of seowon ordered by Regent Heungseon in the 19th century. The original seowon was renowned as a representative example showing the typical lecture hall in front and dormitory at the back (jeondanghujae) layout of the Giho School built in 1650. Two archaeological excavations were conducted in the lecture hall courtyard in 2004 and 2007~2008, which prompted debates the position of the dormitories in respect to the lecture hall, whether the dormitories should be placed in front, or at the back of the lecture hall. Simgok Seowon had been long known as a representative example of the lecture hall in front layout, but the excavations revealed contrasting evidence, suggesting the possibility for a dormitories in front layout. Recent studies and evidence show that the architecture of Simgok Seowon can be grouped into three phases. The first phase was when the shrine and both dormitories were built to the rear of the lecture hall, the second phase was when the lecture hall, Imsimnu Pavilion, Sananggak and Munhyanggak buildings were built, and lastly the third phase when the east, west dormitories were reconstructed in front of the lecture hall. The large scale construction of Simgok Seowon is related to the education based management of the academy by Doam Yi Jae, and the 17~18th century remains confirmed from the archaeological excavations are evidence of this. Remains for Imsimnu Pavilion, Sananggak, and Munhyanggak buildings have yet to be confirmed, and spaces to the south and east of the seowon are unidentified. Therefore, it is necessary to conduct investigations and research for the unexcavated spaces of the seowon, to conduct in-depth studies and for the effective adaptive re-use of the seowon.