• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.108-110
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• 1999

In this paper, approximate means of estimating the flux and torque levels in an induction motor is discussed. There exists several method that is used directly by flux meter and flux sensing coils in the airgap. Most of these methods are sensitive to motor parameter value changes. Also, the harmonics in the motor voltage and current due to the nonsinusodial inverter waveform cause errors in the estimated torque. Finally, this result is applicated in arch type linear induction motor for study of noise and vibration.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.892-894
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• 1995

This paper deals with developmeant and application of coating thickness control system in hot dip galvanizing process. According to the line conditions, such as line speed, strip size and target coating weight, a predictive preset model sets the initial oprating conditions. Referring the zine coating informations from the gauge, mean coating value controller adjusts the chamber pressure and horizontal distance between strip and air knife, while coating deviation controller adjusts the lip gap profile of the air knife. All adaptive gains are interactively calculated by numeric models based on the theoretical analysis. The operating result with this system effectively reduces the coating deviation in transverse direction as well as in longitudinal direction.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.98-99
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• 2014

Construction equipment cost is critical to estimate the total construction costs, particularly in large and complicated projects. Despite its importance, the construction equipment cost may not reflect the current market value since the equipment database is being updated every 6 years at most. To keep construction equipment cost up to date, it is highly recommended to use the standard market price that is reported each year by the Ministry of Security and Public Administration (MOSPA). However, there is still a gap to adopt the standard market price system for the construction equipment cost computing system. Therefore, this paper suggests an effective way to develop a construction equipment cost estimation system.

• 대한기계학회논문집B
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• 제23권7호
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• pp.820-830
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• 1999

The coupled turbulent flow and solidification is considered in a typical slab continuous easting process using commercial program FIDAP. Standard $k-{\varepsilon}$ turbulence model is modified to decay turbulent viscosity in the mushy zone and laminar viscosity is set to a sufficiently large value at the solid region. This coupled turbulent flow and solidification model also contains thermal contact resistance due to the mold powder and air gap between the strand and mold using an effective thermal conductivity. From the computed flow pattern, the trajectory of inclusion particles was calculated. The comparison between the predicted and experimental solidified shell thickness shows a good agreement.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2002년도 제7차 학술대회 초록집
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• pp.84-84
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• 2002

목적： 야간성 전두협 발작 (Nocturnal frontal lobe epilepsy NFLE)은 임상적으로 특징적인 야간성 운동성 발작으로 잘 알려져 있지만 일반적인 MR 영상에서는 대부분에서는 특이한 소견을 보이지 않아 확산 텐서 영상 (DTI)에서의 이상 소견 발현 유무를 알아보고자 한다. 대상 및 방법： 임상적 소견과, EEG 소견으로 진단된 NFLE 환자 6명을 대상으로 DTI 영상을 촬영하였다. 남자 2명, 여자 4명으로 평균연령은 32세 이었다. DTI영상은 single shot spin echo EPI 펄스 열을 사용하였고 사용한 영상 변수는 b value는 0, 1000 s/$\textrm{mm}^2$, TR 10000 msec, TE 71.8/72.3 msec, matrix 128$\times$128 (256 reconstruction), FOV 23cm, 5mm thickness, 2mm interstice gap, NEX 1. 19 slices, time은 4min 21sec (25방향) 이었다. 대조군으로 정상 성인 10명 (평균연령 31세)에서 동일한 방법으로 DTI 영상을 시행하여 분할 비등방도 (fractional anisotropy) 영상을 얻고 전두엽 백질에서 분할 비등방도 값을 측정하여 NFLE 환자군과 비교하였다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.35-39
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• 2005

This paper presents a method to reduce hysteresis in multilayer ceramic actuator by connecting the actuator with a capacitor in a series circuit. The change in hysteresis with respect to the capacitor was examined. $0.2Pb(Mg_{1/3}Nb_{2/3})O_3-0.8Pb(Zr_{0.475}Ti_{0.525})O_3$ ceramic material was used as a piezoelectric material for the actuator. Displacement of the actuator was measured in a capacitive gap sensor measuring system. In case of inserting a capacitor in a total circuit, hysteresis became dramatically decreased, and then finally the hysteresis value can be reduced below $0.2\%$. It was found in this present study that reducing the hysteresis in the actuator is dependent upon the characteristics of the capacitor in total circuit and also operating frequency.

• 한국공작기계학회논문집
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• 제18권1호
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• pp.22-28
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• 2009

In order to optimize the polishing process, Run to Run control scheme has been applied to the micro mold polishing in this study. Also, to fully understand the effect of parameters on the surface roughness a design of experiment is performed. By linear approximation of main factors such as gap and rotational speed of micro quill, EWMA (Exponential Weighted Moving Average) gradual mode controller is adopted as a optimizing tool. Consequently, the process converged quickly at a target value of surface roughness Ra 10nm and Rmax 50nm, and was hardly affected by unwanted process noises like initial surface quality and wear of magnetic abrasives.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제16권2호
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• pp.93-106
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• 2013

분수 나눗셈 알고리즘에 대한 학생들의 어려움 중 상당부분은 현행 교과서의 알고리즘 유도방법 자체에 기인한 것으로 보인다. 본 연구에서는 분수 나눗셈 알고리즘을 유도하는 대안적 방법들 중 단위비율 결정 맥락의 교육적 가치를 분석하고 학생들에 대한 설문과 면담을 통해 그 실제 도입의 가능성을 확인하였다. 또한 이 결과를 바탕으로 분수 나눗셈의 지도 방법 및 교육과정 구성에 대한 대안적 방법을 제안하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.61-65
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• 2003

A magnetic field sensor is fabricated with superconducting ceramics system The prepared material shows the superconductivity at about 95K. The sensor at liquid nitrogen temperature shows the increase in electrical resistance by applying magnetic field. Actually, the voltage drop across the sensor is changed from zero to a value more than $100{\mu}V$ by the applied magnetic field. The change in electrical resistance depends on magnetic field. The sensitivity of this sensor is 2.9 ohm/T. The increase in electrical resistance by the magnetic field is ascribed to a modification of the Josephson junctions due to the penetrating magnetic flux into the superconducting material.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.49-51
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• 1996

The z-transform method is a basic mathematical tool in analyzing and designing sampled-data control systems. However, since the z-transform method relates only the sampling-instants signals, another mathematical tool is necessary to describe the continous signals between the sampling instants. For this purpose the delayed and the modi fled z-transform methods were developed. The definition of the modi fled z-transform includes a sample in the interval [-T,0] of the original signal in its series expression, where the signal value is always zero for any physical system. From this reason one step skew of the time index always appears in its application formulas. This introduces an unnecessary operation and a gap in linking the mathematical formula and its physical interpretation. Considering the conceptual difficulty and application inconvenience, a method of using the advanced z-transform in analysis of sampled-data control systems is developed as a replacement of the modi fled z-transform. With one formulation of the advanced z-transform, now it is possible to relate both the signals of the sampling instants and those in between without any complication and conceptual difficulty.